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The hydroxylation and acetylation of 0.5 mM sulphadimidine (SDD) was studied in primary cultures of hepatocytes from male and female rats, and from castrated male and sham operated male rats. In addition, SDD metabolism was investigated in hepatocytes from castrated male rats treated with testosterone, prior to liver cell isolation. In male rat hepatocytes a significantly higher hydroxylation activity was observed than in hepatocytes from female and castrated male rats. Acetylation activity was higher in females. Testosterone induced hydroxylation but did not affect acetylation. These results correlate well with data from previous in vivo studies, showing the relevance of this in vitro model.  相似文献   
996.
Trypanosoma evansi is the cause of surra, a camel disease which is the most important single cause of economic losses in camel rearing areas. Sheep and goats herded with camels are the most likely hosts for T evansi. Upon intravenous infections goats developed erratic parasitaemia, lost weight and their packed cell volume dropped significantly (P<0–001). Trypanosomes were demonstrated by direct microscopy in extravascular locations such as synovial, peritoneal and cerebrospinal fluids and also in lymph by subinoculations into mice. The carcases were emaciated and pale. Histologically there was lymphatic tissue hyperplasia, muscular atrophy and nephrotic changes. Two animals had necrotic foci in the liver, kidneys, lymph nodes, spleen and lungs and also bronchopneumonia. Histologically there was depopulation of lymphocytes in lymphatic tissues, destruction of hepatocytes in the liver with infiltration by inflammatory cells in the liver, lymph nodes, spleen and the kidneys.  相似文献   
997.
Topical 0.1% tacrolimus was used for treatment of localized lesions associated with 10 cases of discoid lupus erythematosus (DLE) and two cases of pemphigus erythematosus (PE) either as a sole therapy (n=2) or as an adjunctive treatment (n=10). Eight of 10 dogs with DLE and both dogs with PE were improved following 8 weeks of topical application. In six of the eight dogs that improved, other medications were discontinued. No adverse effects in clinical or laboratory parameters were noted throughout the study.  相似文献   
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Accurate antimicrobial drug use data are needed to enlighten discussions regarding the impact of antimicrobial drug use in agriculture. The primary objective of this study was to investigate the perceived accuracy and clarity of different methods for reporting antimicrobial drug use information collected regarding beef feedlots. Producers, veterinarians, industry representatives, public health officials, and other knowledgeable beef industry leaders were invited to complete a web-based survey. A total of 156 participants in 33 US states, 4 Canadian provinces, and 8 other countries completed the survey. No single metric was considered universally optimal for all use circumstances or for all audiences. To effectively communicate antimicrobial drug use data, evaluation of the target audience is critical to presenting the information. Metrics that are most accurate need to be carefully and repeatedly explained to the audience.  相似文献   
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In horses, twin pregnancy is pathological and represents a potentially life‐threatening condition to the mare and foal. Twinning occurs in approximately 2% of pregnancies. Of these, the majority of cases are dizygotic twins, resulting from 2 ovulations and monozygotic twins are rare. A 12‐year‐old Quarter Horse mare was presented for breeding management with shipped cooled semen and embryo transfer. Seven days post ovulation, a single late morula/early blastocyst was recovered and transferred immediately to a recipient mare. Thirty‐six days after transfer, transrectal ultrasound examination revealed the presence of 2 embryos. A transcutaneous reduction of one of the fetuses was performed successfully at 128 days of gestation. This report is the first to describe a successful reduction of monozygotic twins by transcutaneous ultrasound‐guided cardiac puncture.  相似文献   
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