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81.
The chiral inversion process is a characteristic metabolic pathway for different aryl-2-propionic acids or profens. Important variations have been observed between these individual compounds as well as between animal species. In this study, R(-) fenoprofen [R(-)FPF] and R(-) ketoprofen [R(-) KTF] were used to investigate their comparative stereoconversion in cats. After intravenous (i.v.) administration of R(-) FPF, the percentage of chiral inversion was 93.20+/-13.70%. A highly significant correlation (r: 0.978) was observed between the clearance of R(-) FPF and the chiral inversion process. After i.v. administration of R(-) KTF, the percentage of inversion was only 36.73+/-2.8%. No correlation between the clearance of R(-) KTF and this process was observed. R(-) FPF was metabolized by the pathways of thioesterification - chiral inversion processes. For R(-) KTF, the competitive metabolic pathways, glucuronidation and hydroxylation may be involved. However, these metabolic steps are saturable or less functional in cats. Moreover, the thioesterification of R(-) KTF in in vitro studies has been shown to be important in carnivores. The lack of correlation between clearance and chiral inversion process of R(-) KTF may be finally explained by deviation of thioesterification to other metabolic pathways of lipids and/or aminoacid conjugation, particulary glicine derivatives.  相似文献   
82.
在寻找能将犊牛与其母牛分开的理想的肉牛放牧方法中,做了两个试验,以弄清限制哺乳对母牛及其犊牛的影响。试验1中,在产犊后4天将21对母子分成三组,即每日一次哺乳组(1S)、每日两次哺乳组(2S)和哺乳对照  相似文献   
83.
Propofol is an injectable anaesthetic that is currently used both in veterinary and human medicine for the induction and maintenance of anaesthesia. Although little is known about the pharmacokinetics of propofol in fetuses, it is widely used in obstetric procedures, particularly in caesarean section. This study determines the pharmacokinetics of propofol in pregnant ewes in the last third of pregnancy, and placental transfer and pharmacokinetics in fetuses after the administration of a 6 mg/kg intravenous (i.v.) bolus (phase 1) or a 6 mg/kg i.v. bolus followed by continued infusion of 0.4 mg/kg/min. In ewes, the area under the blood concentration-time curve (AUC) and C(max) (8.6 mgh/mL and 9.5mg/mL, respectively) was higher than those of the fetus (1.6 mgh/mL and 1.19 mg/mL, respectively). The mean half-life was 0.5h in the dam and 1.1h in the fetus.  相似文献   
84.
Muscle growth was studied in larvae of sea bass, Dicentrarchus labrax L., reared at two temperatures: real ambient temperature ( congruent with 15 degrees C during vitelline phase and increased gradually) and 19 degrees C from fertilization until the end of larval development. Muscle cellularity, body length and body weight were measured. Early temperature influenced larval development and so, pre-larval phase finished earlier at 19 degrees C than at ambient temperature (4 and 6 days, respectively). Temperature also affected muscle growth such that at hatching and at mouth opening hypertrophy of muscle fibres was greater at 19 degrees C (P < 0.05), whereas hyperplasia was similar in both groups. After 25 days, the cross-sectional area of the white muscle was greater at 19 degrees C (P < 0.05), which was mainly associated with a higher proliferation of new white muscle fibres. At this stage the body length was also higher at 19 degrees C. Metamorphosis finished earlier in fish reared at 19 degrees C (52 days) than at natural temperature (82 days). At this developmental stage body length and cross-sectional area of the myotome were similar in both groups. However, muscle cellularity differed between groups. Thus, hypertrophy of muscle fibres was higher in fish reared at ambient temperature (P < 0.05), whereas proliferation of new muscle fibres was higher at 19 degrees C (P > 0.05).  相似文献   
85.
86.
Trapped neutrophil syndrome (TNS) is an autosomal recessive inherited neutropenia known in Border Collies since the 1990's. Recently, the causative mutation has been identified in the canine VPS13B gene and a DNA-based diagnosis has now become available. The present paper describes clinical and clinico-pathologic findings in a Border Collie with TNS that was molecularly diagnosed for the first time in Japan. In a 10-week-old male Border Collie with microgenesis and symptoms related to recurrent infections, a hematological examination revealed severe leukopenia due to neutropenia, suggesting the dog to be affected by inherited neutropenic immunodeficiency. Direct DNA sequencing demonstrated that the dog was homozygous for the causative mutation of TNS and both its parents were heterozygous carriers. In addition, a simple and rapid polymerase chain reaction-based length polymorphism analysis coupled with microchip electrophoresis was developed for the genotyping of TNS. This assay could discriminate clearly all genotypes, suggesting that it was suitable for both individual diagnosis and large-scale surveys for prevention.  相似文献   
87.
The meat of wild boar (Sus scrofa L.) can be a source of human infections with zoonotic parasites Toxoplasma gondii and Trichinella spp. We screened 197 wild boar sera collected at slaughter from 25 Finnish farms in 2007-2008 for serological evidence of infections with these parasites. Using a commercial direct agglutination test at a serum dilution of 1:40, T. gondii-specific IgG antibodies were detected in 65 (33.0%) samples, on 14 (56.0%) farms. Females, animals older than 24 months, animals of small herds, and animals originating from south-western parts of Finland were more often T. gondii-seropositive than were males, younger animals, animals of larger herds, and animals originating from the north and east, respectively. Four (2.0%) of the sera, originating from three (12.0%) farms, tested Trichinella-seropositive with an in-house ELISA and a conservative cut-off for seropositivity. One farm had both T. gondii- and Trichinella-seropositive animals. Taken together, an infection source had been present on 16 (64.0%) farms, and 69 (35.0%) of the 197 farmed wild boars intended for human consumption had specific serological evidence of exposure to a zoonotic parasite.  相似文献   
88.
旨在分析禽腺病毒血清4型(FAdV-4)感染鸡组织中NLRP3基因的转录水平,本研究设计鸡NLRP3特异性引物,利用RT-PCR扩增NLRP3基因180 bp片段并克隆至pMD-18T载体,制备重组质粒pMD-18T-NL-RP3.以pMD-18T-NLRP3质粒作为标准品进行荧光定量PCR并建立标准曲线.通过反应条件...  相似文献   
89.
The prevalence and risk factors associated with leptospirosis were studied in veterinary students in Zaragoza. Sera were collected at the beginning and end of the academic year 1994 to 1995 and were tested by ELISA against a pool of Leptospira interrogans serovars bratislava, canicola, grippotyphosa, hardjo, icterohaemorrhagiae and pomona antigens. At the beginning of the study the prevalence was 8.14 per cent and at the end it was 11.4 per cent. The incidence of the disease during the study was 0.0394. Risk factors associated with leptospirosis included: taking the course specialising in food inspection and technology, on-farm work, contact with pets in general, and particularly carnivores, and contact with animal traders. The symptoms associated with the disease were myalgia and fever, and the treatment of the symptoms provided some protection.  相似文献   
90.
OBJECTIVE: To determine the maximally tolerated dose (MTD) and dose-limiting toxicosis (DLT) of ifosfamide in tumor-bearing cats. ANIMALS: 38 cats with resected, recurrent, or metastatic sarcomas. PROCEDURE: The starting dosage of ifosfamide was 400 mg/m(2) of body surface area, IV, and dosages were increased by 50 to 100 mg/m(2) in cohorts of 3 cats. To protect against urotoxicosis, mesna was administered at a dosage equal to 20% of the calculated ifosfamide dosage. Diuresis with saline (0.9% NaCl) solution before and after administration of ifosfamide was used to minimize nephrotoxicosis. Samples for pharmacokinetic analysis were obtained after the MTD was reached. RESULTS: 38 cats were entered into this phase I study and were administered a single dose of ifosfamide at various dosages. The MTD was 1,000 mg/m(2), and neutropenia was the DLT. Seven of 8 episodes of neutropenia were on day 7 after treatment, and 1 cat developed severe neutropenia on day 5. Adverse effects on the gastrointestinal tract were generally mild and self-limiting, the most common of which was nausea during ifosfamide infusion. One cat had signs consistent with a drug-induced hypersensitivity reaction. There were no episodes of hemorrhagic cystitis or nephrotoxicosis. Correlations between pharmacokinetic variables and ifosfamide-associated toxicoses were not found. Preliminary evidence of antitumor activity was observed in 6 of 27 cats with measurable tumors. CONCLUSIONS AND CLINICAL RELEVANCE: The dosage of ifosfamide recommended to treat tumor-bearing cats is 900 mg/m(2) every 3 weeks. This dosage should be used in phase II clinical trials.  相似文献   
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