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排序方式: 共有588条查询结果,搜索用时 265 毫秒
1.
Daniel J. Burba DVM Michael A. Collier DVM Lawrence E. Default PhD Olivia Hanson-Painton PhD Harold C. Thompson Jr. Claude L. Holder 《Journal of Equine Veterinary Science》1993,13(12):696-703
The uptake and distribution of intramuscularly (IM) administered tritium-labeled polysulfated glycosaminoglycan (3H-PSGAG) in serum, synovial fluid, and articular cartilage of eight horses was quantitated, and hyaluronic acid (HA) concentration of the middle carpal joint was evaluated in a pharmacokinetic study. A full-thickness articular cartilage defect, created on the distal articular surface of the left radial carpal bone of each horse served as an osteochondral defect model. 3H-PSGAG (500 mg) was injected IM, between 14 and 35 days after creation of the defects. Scintillation analysis of serum and synovial fluid, collected from both middle carpal joints at specific predetermined times up to 96 hours post-injection, revealed mean 3H-PSGAG concentrations peaked at 2 hours post-injection. 3H-PSGAG was detected in cartilage and subchondral bone 96 hours post-injection in samples from all eight horses. There were no statistically significant differences in 3H-PSGAG concentration of synovial fluid or cartilage between cartilage defect and control (right middle carpal) joints.
HA assay of synovial fluid revealed concentrations significantly increased at 24, 48, and 96 hours post-injection in both joints. The concentration nearly doubled 48 hours post-injection. However, no statistically significant differences were found between synovial concentrations of HA in cartilage defect and control joints.
3H-PSGAG administered IM to horses, was distributed in the blood, synovial fluid, and articular cartilage. HA concentrations in synovial fluid increased after IM administration of polysulfated glycosaminoglycan. 相似文献
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Tea Bai J. Robert Britton Stephen P. Rice Andrew G. Pledger 《Ecology of Freshwater Fish》2019,28(1):110-122
The spawning success of lithophilic salmonids is strongly influenced by the fine sediment content (“fines”) of spawning substrates, yet knowledge on the impacts of fines on the spawning of non‐salmonid lithophiles remains limited, despite their ecological and socio‐economic importance in European rivers. Consequently, the aim here was to use an ex‐situ experiment to investigate the impact of sand content on egg survival and timing of larval emergence of the surface‐spawning cyprinid European barbel Barbus barbus. Thirty incubator boxes within a recirculating system were filled with one of five experimental sediment mixtures (0%–40% sand by mass) that each contained 300 fertilised eggs at a depth of 50 mm. Emerged, free‐swimming larvae were captured and counted daily to assess grain‐size effects on larval survival and emergence. Specifically, total proportion of emerged larvae, cumulative daily proportion of emerged larvae and time required to reach 50% emergence were measured during the study. Whilst the proportion of sand in the sediments did not have a significant impact on egg‐to‐emergence survival (mean survival per treatment 75%–79%), it significantly affected the timing of larval emergence to the water column; early emergence was detected in treatments with elevated sand content (on average, 50% emergence after 12–13 days versus 19 days in the control). Similar to findings from salmonid studies, these results suggest high sand content in spawning gravels can influence timing of larval emergence and potentially cyprinid lithophilic fish survival. 相似文献
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Inoue OJ Freeman DE Wallig MA Clarkson RB 《American journal of veterinary research》2007,68(3):305-312
OBJECTIVE: To determine effects of reactive oxygen metabolites (ROMs), with and without flunixin meglumine, on equine right ventral colon (RVC) in vitro. ANIMALS: 18 healthy horses and ponies. PROCEDURES: In 3 groups of 6 animals each, short-circuit current and conductance were measured in RVC mucosa in Ussing chambers. The 3 groups received physiologic saline (0.9% NaCl) solution, IV, 10 minutes before euthanasia and tissue incubation in Krebs-Ringer-bicarbonate (KRB) solution; flunixin meglumine (1.1 mg/kg, IV) 10 minutes before euthanasia and tissue incubation in KRB solution; or physiologic saline solution, IV, 10 minutes before euthanasia and incubation in KRB solution with 2.7 x 10(5)M flunixin meglumine. Incubation conditions included control (no addition) and ROM systems, including addition of 1 mM xanthine and 80 mU of xanthine oxidase (to produce the superoxide radical), 1 mM H(2)O(2), and 1 mM H(2)O(2) and 0.5 mM ferrous sulfate (to produce the hydroxyl radical). RESULTS: All ROMs that were added or generated significantly increased the short-circuit current except in tissues coincubated with flunixin meglumine, and they induced mild epithelial vacuolation and apoptosis, but did not disrupt the epithelium nor change conductance, lactate dehydrogenase release, or [(3)H]mannitol flux. CONCLUSIONS AND CLINICAL RELEVANCE: Responses to ROMs could be attributed to increased chloride secretion and inhibited neutral NaCl absorption in equine RVC, possibly by stimulating prostaglandin production. The ROMs examined under conditions of this study could play a role in prostaglandin-mediated colonic secretion in horses with enterocolitis without causing direct mucosal injury. 相似文献
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Clinical and in vitro efficacy of amoxicillin against bacteria associated with feline skin wounds and abscesses 总被引:1,自引:0,他引:1
Roy J Messier S Labrecque O Cox WR 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(6):607-611
A clinical trial involving 122 cats with infected skin wounds or abscesses presented to 10 veterinary clinics was conducted to evaluate the efficacy of 2 oral amoxicillin drug products (a paste and a suspension). A 2nd objective of the study was to identify bacteria involved in such infections and verify their in vitro sensitivity to amoxicillin. Samples of wound exudate were harvested at the time of presentation and submitted for aerobic and anaerobic culture. The sensitivity to amoxicillin of isolates thought to be infecting agents was tested, using a standard minimum inhibitory concentration method. Pasteuralla multocida and obligate anaerobes of the genera Prevotella, Fusobacterium, and Porphyromonas were the most frequently isolated pathogens. Overall, their in vitro susceptibility to amoxicillin was very good. Both drug products were clinically efficacious with a global success rate of 95.1% for cats administered oral amoxicillin at 11-22 mg/kg bodyweight (mean 13.8 mg/kg bodyweight) twice daily for 7 to 10 days. 相似文献
8.
Monoterpenoid derivatives were synthesized and their insecticidal activities were evaluated against red flour beetles, Tribolium castaneum (Herbst), in fumigant bioassays and against house flies Musca domestica (L.) in topical, fumigant, and ovicidal bioassays. Acetate derivatives and haloacetate derivatives were compared with each other, and with the parent monoterpenoid to determine structure-activity relationships. Acetate derivatives were more active than the propionate derivatives of cyclic monoterpenoids in the topical, fumigant, and ovicidal bioassays. Pivalates were topically more insecticidal than acetates to adult house flies, while the acetates had the greater ovicidal activity. Acetates and pivalates were more effective than haloacetates in the topical, red flour beetle fumigation and ovicidal bioassays. Fluoroacetates of cyclic monoterpenoids were the most effective house fly fumigants, followed by acetates, and trichloroacetates. Several derivatives were produced that displayed enhanced activity relative to the parent alcohols or phenols. 相似文献
9.
The clinical pathology and histopathology of two groups of Atlantic salmon with severe degenerative myopathy (pancreas disease) is described and compared with a third healthy group. One affected group was anorexic and had low plasma protein and albumin levels while the other was feeding and had normal levels. Both diseased groups had plasma and tissue vitamin E and selenium levels lower than the healthy group. Similarly, creatine kinase values were raised in affected groups. If representative of the syndrome as a whole, the results suggest that the myopathy of pancreas disease has a basis in a vitamin E-selenium deficiency, but whether primary or induced is not clear. The results also demonstrate that the myopathy and pancreatic atrophy do not inevitably lead to anorexia or any other clinically obvious sign of disease, despite both cardiac and oesophageal involvement. 相似文献
10.
Factors affecting dystocia in beef heifers 总被引:3,自引:0,他引:3
L E Rice J N Wiltbank 《Journal of the American Veterinary Medical Association》1972,161(11):1348-1358