| Records |
| Author |
Schwarzenberger, F.; Mostl, E.; Bamberg, E.; Pammer, J.; Schmehlik, O. |
| Title |
Concentrations of progestagens and oestrogens in the faeces of pregnant Lipizzan, trotter and thoroughbred mares |
Type |
Journal Article |
| Year |
1991 |
Publication |
Journal of reproduction and fertility. Supplement |
Abbreviated Journal |
J Reprod Fertil Suppl |
| Volume |
44 |
Issue |
|
Pages |
489-499 |
| Keywords |
Animals; Estrogens/*analysis; Feces/*chemistry; Female; Gestational Age; Horses/*metabolism; Immunoenzyme Techniques; Labor, Obstetric; Pregnancy; Pregnancy, Animal/*metabolism; Pregnenes/analysis; Progestins/*analysis |
| Abstract |
Faecal samples were collected at weekly intervals from pregnant Lipizzan mares during Weeks 7-16 following mating and from Lipizzan, Trotter and Thoroughbred mares during the last 3 months of gestation. After parturition, samples were taken daily from the Thoroughbred mares for another 6 days. Non-pregnant mares served as controls. The concentrations of unconjugated oestrogens (Eg), 20 alpha-OH-progestagens (20 alpha-G) and 20 beta-OH-progestagens (20 beta-G) were measured by enzyme immunoassay. In the faeces of Lipizzan mares, immunoreactive progestagens were significantly (P less than 0.01) elevated above the levels in non-pregnant mares by Week 11, and Eg by Week 13 of pregnancy onwards. During the last 3 months of gestation, concentrations of Eg were significantly higher in Trotter mares than in Lipizzan and Thoroughbred mares. Concentrations of 20 alpha-G and 20 beta-G increased to maximal values in the last month of gestation. There was no significant difference among the 3 breeds with respect to 20 alpha-G but, during the 10 weeks before parturition, concentrations of 20 beta-G in the Lipizzan mares were significantly lower (P less than 0.05) than those in the Thoroughbred mares. They were also significantly lower than those of the Trotter mares during the last 4 weeks of gestation. After parturition, the concentrations of Eg and progestagens had declined to baseline values by Days 3 and 4 respectively. From these results we conclude that high concentrations of progestagens with 20 alpha- and 20 beta-hydroxyl groups are present in the faeces of pregnant mares, especially during the last month of gestation. |
Address  |
Institut fur Biochemie, Veterinary Medical University, Vienna, Austria |
| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0449-3087 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:1795293 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
322 |
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| Author |
Reynhout, I.C.; Cornelissen, J.J.L.M.; Nolte, R.J.M. |
| Title |
Self-assembled architectures from biohybrid triblock copolymers |
Type |
Journal Article |
| Year |
2007 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| Volume |
129 |
Issue |
8 |
Pages |
2327-2332 |
| Keywords |
Horseradish Peroxidase/*chemistry; Micelles; Molecular Structure; Myoglobin/*chemistry; Particle Size; Polyethylene Glycols/*chemistry; Polymers/*chemical synthesis/chemistry; Polystyrenes/*chemistry; Surface-Active Agents/chemical synthesis/chemistry |
| Abstract |
The synthesis and self-assembly behavior of biohybrid ABC triblock copolymers consisting of a synthetic diblock, polystyrene-b-polyethylene glycol (PSm-b-PEG113), where m is varied, and a hemeprotein, myoglobin (Mb) or horse radish peroxidase (HRP), is described. The synthetic diblock copolymer is first functionalized with the heme cofactor and subsequently reconstituted with the apoprotein or the apoenzyme to yield the protein-containing ABC triblock copolymer. The obtained amphiphilic block copolymers self-assemble in aqueous solution into a large variety of aggregate structures. Depending on the protein and the polystyrene block length, micellar rods, vesicles, toroids, figure eight structures, octopus structures, and spheres with a lamellar surface are formed. |
| Address |
Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0002-7863 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:17274615 |
Approved |
no |
| Call Number |
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Serial |
1832 |
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| Author |
Machnik, M.; Hegger, I.; Kietzmann, M.; Thevis, M.; Guddat, S.; Schanzer, W. |
| Title |
Pharmacokinetics of altrenogest in horses |
Type |
Journal Article |
| Year |
2007 |
Publication |
Journal of Veterinary Pharmacology and Therapeutics |
Abbreviated Journal |
J Vet Pharmacol Ther |
| Volume |
30 |
Issue |
1 |
Pages |
86-90 |
| Keywords |
Administration, Oral; Animals; Chromatography, Liquid/veterinary; Doping in Sports/prevention & control; Horses/*metabolism; Male; Mass Spectrometry/veterinary; Progesterone Congeners/administration & dosage/blood/*pharmacokinetics/urine; Reproducibility of Results; Substance Abuse Detection/veterinary; Trenbolone/administration & dosage/*analogs & derivatives/blood/pharmacokinetics/urine |
| Abstract |
The Federation Equestre Internationale has permitted the use of altrenogest in mares for the control of oestrus. However, altrenogest is also suspicious to misuse in competition horses for its potential anabolic effects and suppression of typical male behaviour, and thus is a controlled drug. To investigate the pharmacokinetics of altrenogest in horses we conducted an elimination study. Five oral doses of 44 mug/kg altrenogest were administered to 10 horses at a dose interval of 24 h. Following administration blood and urine samples were collected at appropriate intervals. Altrenogest concentrations were measured by liquid chromatography-tandem mass spectrometry. The plasma levels of altrenogest reached maximal concentrations of 23-75 ng/mL. Baseline values were achieved within 3 days after the final administration. Urine peak concentrations of total altrenogest ranged from 823 to 3895 ng/mL. Twelve days after the final administration concentrations were below the limit of detection (ca 2 ng/mL). |
| Address |
Institute of Biochemistry, German Sport University, Cologne, Germany. m.machnik@biochem.dshs-koeln.de |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0140-7783 |
ISBN |
|
Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:17217407 |
Approved |
no |
| Call Number |
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Serial |
1841 |
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| Author |
Bell, R.J.W.; Kingston, J.K.; Mogg, T.D.; Perkins, N.R. |
| Title |
The prevalence of gastric ulceration in racehorses in New Zealand |
Type |
Journal Article |
| Year |
2007 |
Publication |
New Zealand Veterinary Journal |
Abbreviated Journal |
N Z Vet J |
| Volume |
55 |
Issue |
1 |
Pages |
13-18 |
| Keywords |
Age Factors; *Animal Feed; Animal Husbandry/methods; Animals; Female; Horse Diseases/*epidemiology/pathology/prevention & control; Horses; Male; New Zealand/epidemiology; Physical Conditioning, Animal/*adverse effects/physiology; Poaceae; Prevalence; Risk Factors; Severity of Illness Index; Sex Factors; Stomach Ulcer/epidemiology/pathology/prevention & control/*veterinary; Time Factors |
| Abstract |
AIM: To establish the prevalence and factors influencing the prevalence and severity of gastric ulceration in racehorses in New Zealand. METHODS: Horses (n=171) in active training for racing by trainers (n=24) located throughout New Zealand were examined using gastroscopy during 2003 and 2004. Images of the examination were recorded and reviewed, and an ordinal grade based on the severity of gastric ulceration present was assigned, using the grading system proposed by the Equine Gastric Ulcer Council (EGUC). Information about the horses such as age, breed, sex, stabling, time at pasture, pasture quality, and presence of clinical signs consistent with equine gastric ulcer syndrome (EGUS) was recorded. RESULTS: Of the 171 horses in the study, 133 (78%) were Thoroughbreds and 38 (22%) were Standardbreds. Evidence of gastric ulceration was present in 151 (88.3%) of these. Prevalence of ulceration was higher at the lesser curvature (LC) and greater curvature (GC) of the stomach than at the saccus caecus (SC; p<0.01), and ulceration was more severe at the LC than at either the GC (p=0.02) or the SC (p<0.001). The prevalence of ulceration did not differ between the two breeds (p=0.51) or between horses of differing ages (p=0.56). Gastric ulceration was evident in 125/141 (89%) horses kept at pasture for at least 4 h/day, in all 13 (100%) horses kept at pasture full time, and in 16/17 (94%) horses stabled full time. Prevalence and severity of ulceration did not differ between horses stabled full time, kept at pasture for part of the day or kept at pasture full time (p=0.33 and 0.13, respectively), and for horses grazed on pasture severity of ulceration did not vary significantly with the quality of the pasture (p=0.12). Neither prevalence (p=0.26) nor severity (p=0.49) of gastric ulceration varied significantly with duration of training. CONCLUSIONS: The prevalence of gastric ulceration in racehorses in New Zealand is similar to that reported elsewhere for horses in active training for racing. Access to pasture for some or all of the day did not appear to be protective. |
| Address |
Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand. robinjw@gmail.com |
| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0048-0169 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:17339911 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4020 |
| Permanent link to this record |
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| Author |
Kraft, C.N.; Urban, N.; Ilg, A.; Wallny, T.; Scharfstadt, A.; Jager, M.; Pennekamp, P.H. |
| Title |
[Influence of the riding discipline and riding intensity on the incidence of back pain in competitive horseback riders] |
Type |
Journal Article |
| Year |
2007 |
Publication |
Sportverletzung Sportschaden : Organ der Gesellschaft fur Orthopadisch-Traumatologische Sportmedizin |
Abbreviated Journal |
Sportverletz Sportschaden |
| Volume |
21 |
Issue |
1 |
Pages |
29-33 |
| Keywords |
Adolescent; Adult; Aged; Animals; Child; Female; Horses; Humans; Incidence; Low Back Pain/diagnosis/*epidemiology/etiology; Male; Middle Aged; Pain Measurement; Questionnaires; Risk Factors; *Sports/physiology |
| Abstract |
INTRODUCTION: The connection between morphologic changes of the spine and the intensity of training has been assessed for a number of sport activities. The influence of horseback riding on the spine has only rarely been evaluated. The aim of our study was to evaluate to what degree horseback riders suffer from back pain and whether there is an association between this parameter and the category i. e. the intensity of horseback riding. Furthermore we wanted to judge whether riding may have a positive effect on pre-existent back pain. METHODS: 508 horseback riders (63.2 % females; 36.8 % males) competing in either dressage, showjumping or vaulting were interviewed using a questionnaire. Apart from biometric data, the intensity with which riding was performed and the localisation and intensity (VAS) of back pain was assessed. Furthermore, in the case of existing back pain, riders were asked whether different riding disciplines and paces changed the intensity of pain. RESULTS: 300 dressage riders (59.1 %), 188 showjumpers (37.0 %) and 20 vaulters (3.9 %) with an average age of 33.5 Jahre (12 – 77 years) were questioned. The incidence of back pain was 72.5 %. A significant correlation between back pain and riding discipline respectively gender or riding level could not be found. Discrepancies in VAS-score for dressage riders (3.95 +/- 0.13), show jumpers (4.10 +/- 0.16) and vaulters (3.76 +/- 0.5) were marginal and not significant (p > 0.05). Overall 58.7 % resp. 15.2 % reported to have pain in the lumbar i.e cervical spine. Despite the fact that a large fraction of dressage riders claimed to have problems in these spine areas with 57.7 % resp. 68.8 %, this finding was not significant compared to the other riding disciplines. While 61.6 % of dressage riders reported an improvement of their back pain when riding, this was only the case in 40.9 % of show jumpers. CONCLUSION: Compared to the general population, a high incidence of back pain is found among riders. A significant correlation between the intensity of riding or the riding discipline and frequency or severity of back pain could not be found. For riders with pre-existent back pain the pace “walk” seems to have a positive influence on pain intensity. |
| Address |
Klinik und Poliklinik fur Orthopadie, Heinrich-Heine-Universitat, Dusseldorf. clayton.kraft@med.uni-duesseldorf.de |
| Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
German |
Summary Language |
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Original Title |
Einfluss der Reitdisziplin und -intensitat auf die Inzidenz von Ruckenschmerzen bei Reitsportlern |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0932-0555 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:17385102 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3706 |
| Permanent link to this record |
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| Author |
Rapin, V.; Poncet, P.A.; Burger, D.; Mermod, C.; Richard, M.A. |
| Title |
[Measurement of the attention time in the horse] |
Type |
Journal Article |
| Year |
2007 |
Publication |
Schweizer Archiv fur Tierheilkunde |
Abbreviated Journal |
Schweiz Arch Tierheilkd |
| Volume |
149 |
Issue |
2 |
Pages |
77-83 |
| Keywords |
Age Factors; Animals; *Attention/physiology; Conditioning, Operant; Cross-Over Studies; Female; Horses/*physiology; Learning/*physiology; Male; Memory/*physiology; Time Factors |
| Abstract |
A study carried out on 49 horses showed that it is possible to measure the attention time by operant conditioning. After teaching horses an instrumental task using a signal, we were then able to test their attention time by asking them to prolong it increasingly while setting success and failure criteria. Two tests were performed 3 weeks apart. The 2nd test was feasible without relearning, a proof of memory, and was repeatable, a proof of consistency in the attention time. A significant difference was observed between the 3 age groups. Young horses often performed very well during the 1st test but their attention dropped in the 2nd test while older horses were more stable with respect to attention and even increased it slightly. The study shows that there are individual differences but it was not possible to prove a significant influence of breed, gender and paternal influence. Consequently, learning appears to be one of the most interesting approaches for evaluating the attention of horses and for observing their behaviour. |
| Address |
Laboratoire d'Ecoethologie, Universite de Neuchatel, Suisse. veronique.rapin@unine.ch |
| Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
French |
Summary Language |
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Original Title |
Mesure de la duree d'attention chez le cheval |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0036-7281 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:17343134 |
Approved |
no |
| Call Number |
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Serial |
1770 |
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| Author |
Khalil, A.M.; Murakami, N.; Kaseda, Y. |
| Title |
Relationship between plasma testosterone concentrations and age, breeding season and harem size in Misaki feral horses |
Type |
Journal Article |
| Year |
1998 |
Publication |
The Journal of veterinary medical science / the Japanese Society of Veterinary Science |
Abbreviated Journal |
J Vet Med Sci |
| Volume |
60 |
Issue |
5 |
Pages |
643-645 |
| Keywords |
Age Factors; Animals; Animals, Wild; *Horses; Japan; Male; Reproduction; Seasons; Sexual Behavior, Animal; Sexual Maturation; *Social Behavior; Testosterone/*blood |
| Abstract |
Jugular vein blood samples were collected from 23 young and sexual mature feral stallions to examine the relationship between plasma testosterone concentration and age, breeding season or harem size. Testosterone concentration increased with the age of the stallions until they formed their own harems, at about 4 to 6 years old. Seasonal variations in testosterone concentrations were observed, and found to be significantly higher (P<0.001) throughout the breeding season than non-breeding season, from 3 years of age. Testosterone levels were correlated with harem size for individual stallions. It can be inferred from these results that there is a relationship between plasma testosterone concentration and age, breeding season and harem size. |
| Address |
Laboratory of Animal Behavioral Science, Faculty of Agriculture, Miyazaki University, Japan |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0916-7250 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:9637303 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
137 |
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| Author |
Borsari, A.; Ottoni, E.B. |
| Title |
Preliminary observations of tool use in captive hyacinth macaws (Anodorhynchus hyacinthinus) |
Type |
Journal Article |
| Year |
2005 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
| Volume |
8 |
Issue |
1 |
Pages |
48-52 |
| Keywords |
Age Factors; Animals; *Feeding Behavior; Female; *Intelligence; Male; *Motor Skills; *Nuts; *Parrots |
| Abstract |
Many animals use tools (detached objects applied to another object to produce an alteration in shape, position, or structure) in foraging, for instance, to access encapsulated food. Descriptions of tool use by hyacinth macaws (Anodorhynchus hyacinthinus) are scarce and brief. In order to describe one case of such behavior, six captive birds were observed while feeding. Differences in nut manipulation and opening proficiency between adults and juveniles were recorded. The tools may be serving as a wedge, preventing the nut from slipping and/or rotating, reducing the impact of opening, or providing mechanical aid in its positioning and/or use of force. Data suggest that birds of this species have an innate tendency to use objects (tools) as aids during nut manipulation and opening. |
| Address |
Laboratory of Cognitive Ethology, Department of Experimental Psychology, Institute of Psychology, University of Sao Paulo, Sao Paulo, Brazil. borsari@hotmail.com |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1435-9448 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:15248094 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
2518 |
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| Author |
Nicol, C.J.; Adachi, M.; Akiyama, T.E.; Gonzalez, F.J. |
| Title |
PPARgamma in endothelial cells influences high fat diet-induced hypertension |
Type |
Journal Article |
| Year |
2005 |
Publication |
American journal of hypertension : journal of the American Society of Hypertension |
Abbreviated Journal |
Am J Hypertens |
| Volume |
18 |
Issue |
4 Pt 1 |
Pages |
549-556 |
| Keywords |
Administration, Oral; Animals; Antihypertensive Agents/pharmacology; Blood Pressure/drug effects; Diabetes Mellitus, Type 2/physiopathology; Dietary Fats/*administration & dosage/pharmacology; Dose-Response Relationship, Drug; Endothelial Cells/*metabolism; Female; Heart Rate/drug effects; Hypertension/*etiology; Ligands; Male; Mice; Mice, Knockout; PPAR gamma/*metabolism; Sodium Chloride/administration & dosage/pharmacology; Thiazolidinediones/pharmacology |
| Abstract |
BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands improve human hypertension. However, the mechanism and site of this effect remains unknown, confounded by PPARgamma expression in many cell types, including endothelial cells (ECs). METHODS: To evaluate the vascular role of PPARgamma we used a conditional null mouse model. Specific disruption of PPARgamma in ECs was created by crossing Tie2-Cre+ transgenic (T2T+) and PPARgamma-floxed (fl/fl) mice to generate PPARgamma (fl/fl)T2T+ (PPARgamma E-null) mice. Conscious 8- to 12-week-old congenic PPARgamma (fl/fl)Cre- (wild type) and PPARgamma E-null mice were examined for changes in systolic blood pressure (BP) and heart rate (HR), untreated, after 2 months of salt-loading (drinking water), and after treatment for 3 months with high fat (HF) diet alone or supplemented during the last 2 weeks with rosiglitazone (3 mg/kg/d). RESULTS: Untreated PPARgamma E-nulls were phenotypically indistinguishable from wild-type littermates. However, compared to similarly treated wild types, HF-treated PPARgamma E-nulls had significantly elevated systolic BP not seen after normal diet or salt-loading. Despite sex-dependent baseline differences, salt-loaded and HF-treated PPARgamma E-nulls of either sex had significantly elevated HR versus wild types. Interestingly, rosiglitazone improved serum insulin levels, but not HF diet-induced hypertension, in PPARgamma E-null mice. CONCLUSIONS: These results suggest that PPARgamma in ECs not only is an important regulator of hypertension and HR under stressed conditions mimicking those arising in type 2 diabetics, but also mediates the antihypertensive effects of rosiglitazone. These data add evidence supporting a beneficial role for PPARgamma-specific ligands in the treatment of hypertension, and suggest therapeutic strategies targeting ECs may prove useful. |
| Address |
Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA |
| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0895-7061 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:15831367 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
69 |
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| Author |
Cheung, C.; Akiyama, T.E.; Ward, J.M.; Nicol, C.J.; Feigenbaum, L.; Vinson, C.; Gonzalez, F.J. |
| Title |
Diminished hepatocellular proliferation in mice humanized for the nuclear receptor peroxisome proliferator-activated receptor alpha |
Type |
Journal Article |
| Year |
2004 |
Publication |
Cancer research |
Abbreviated Journal |
Cancer Res |
| Volume |
64 |
Issue |
11 |
Pages |
3849-3854 |
| Keywords |
Animals; Anticholesteremic Agents/pharmacology; Carcinogens/pharmacology; Cell Division; DNA Replication/drug effects; Fatty Acids/metabolism; Hepatocytes/cytology/drug effects/metabolism/*physiology; Humans; Mice; Mice, Transgenic; Oxidation-Reduction; Peroxisome Proliferators/pharmacology; Pyrimidines/pharmacology; Receptors, Cytoplasmic and Nuclear/genetics/*physiology; Species Specificity; Transcription Factors/genetics/*physiology |
| Abstract |
Lipid-lowering fibrate drugs function as agonists for the nuclear receptor peroxisome proliferator-activated receptor alpha (PPARalpha). Sustained activation of PPARalpha leads to the development of liver tumors in rats and mice. However, humans appear to be resistant to the induction of peroxisome proliferation and the development of liver cancer by fibrate drugs. The molecular basis of this species difference is not known. To examine the mechanism determining species differences in peroxisome proliferator response between mice and humans, a PPARalpha-humanized mouse line was generated in which the human PPARalpha was expressed in liver under control of the tetracycline responsive regulatory system. The PPARalpha-humanized and wild-type mice responded to treatment with the potent PPARalpha ligand Wy-14643 as revealed by induction of genes encoding peroxisomal and mitochondrial fatty acid metabolizing enzymes and resultant decrease of serum triglycerides. However, surprisingly, only the wild-type mice and not the PPARalpha-humanized mice exhibited hepatocellular proliferation as revealed by elevation of cell cycle control genes, increased incorporation of 5-bromo-2'-deoxyuridine into hepatocyte nuclei, and hepatomegaly. These studies establish that following ligand activation, the PPARalpha-mediated pathways controlling lipid metabolism are independent from those controlling the cell proliferation pathways. These findings also suggest that structural differences between human and mouse PPARalpha are responsible for the differential susceptibility to the development of hepatocarcinomas observed after treatment with fibrates. The PPARalpha-humanized mice should serve as models for use in drug development and human risk assessment and to determine the mechanism of hepatocarcinogenesis of peroxisome proliferators. |
| Address |
Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA |
| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0008-5472 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:15172993 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
74 |
| Permanent link to this record |
