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61.
An enteric infection in cockatoos associated with a 30 nm diameter enterovirus-like agent seen in faeces and intestinal epithelial cells is described. The disease is characterised by intractable, profuse, mucoid diarrhoea, weight loss, dehydration and death. Lesions in the intestine consist of villous atrophy, villous fusion, enterocyte hyperplasia and, in some cases, chronic inflammation. Affected birds so far examined have concurrent psittacine beak and feather disease.  相似文献   
62.
OBJECTIVE: To determine analgesic efficacy and adverse effects of preemptive administration of meloxicam or butorphanol in cats undergoing onychectomy or onychectomy and neutering. DESIGN: Randomized controlled study. ANIMALS: 64 female and 74 male cats that were 4 to 192 months old and weighed 1.09 to 705 kg (2.4 to 15.5 lb). PROCEDURE: Cats received meloxicam (0.3 mg/kg [0.14 mg/lb], s.c.) or butorphanol (0.4 mg/kg [0.18 mg/lb], s.c.) 15 minutes after premedication and prior to anesthesia. A single blinded observer measured physiologic variables, assigned analgesia and lameness scores, and withdrew blood samples for each cat at baseline and throughout the 24 hours after surgery. Rescue analgesia (butorphanol, 0.4 mg/kg, i.v. or s.c.) or administration of acepromazine (0.025 to 0.05 mg/kg [0.011 to 0.023 mg/lb], i.v.) was allowed. RESULTS: Meloxicam-treated cats were less lame and had lower pain scores. Cortisol concentration was higher at extubation and lower at 1, 5, and 12 hours in the meloxicam-treated cats. Fewer meloxicam-treated cats required rescue analgesia at 3, 5, 12, and 24 hours after extubation. General impression scores were excellent or good in 75% of meloxicam-treated cats and 44% of butorphanol-treated cats. There was no treatment effect on buccal bleeding time; PCV and BUN concentration decreased in both groups, and glucose concentration decreased in meloxicam-treated cats. CONCLUSIONS AND CLINICAL RELEVANCE: Preoperative administration of meloxicam improved analgesia for 24 hours without clinically relevant adverse effects in cats that underwent onychectomy or onychectomy and neutering and provided safe, extended analgesia, compared with butorphanol.  相似文献   
63.
Abstract— Plasma concentrations of insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding proteins (IGFBPs) were compared between market sized sunshine and palmetto bass. Differences between male and female fish were examined and both hybrids were sampled before and after a low-water confinement stress. There was no difference in body weight between the hybrid types, however, females were significantly heavier than males in both hybrids. Plasma IGF-I concentrations were significantly higher in pre-stressed palmetto bass when compared with sunshine bass, and male palmetto bass had significantly higher IGF-I concentrations than females. Two hours after a 15-min low-water stress, a significant decrease in palmetto bass IGF-I occurred, but there was no change in sunshine bass IGF-I concentrations. Levels of a 33-kDa IGFBP were similar in pre-stressed palmetto bass when compared with sunshine bass; however, no differences due to gender were evident for either hybrid. Two hours after a 15-min low-water exposure, there was no change in the levels of a 33-kDa IGFBP in palmetto or sunshine bass. A more complete understanding of IGF-I, IGFBPs, and IGF-I receptors may be necessary to explain the role of IGF-I in regulating fish growth.  相似文献   
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65.
为了检测牛GDF-9基因mRNA在怀孕期牛生殖系统的表达情况,为GDF-9基因在雌性动物繁殖上的研究提供一定的理论依据。本试验根据GenBank中报道的牛GDF-9基因序列设计引物,从牛卵巢、输卵管、子宫、肾脏中提取RNA,采用RT-PCR技术进行cDNA扩增,扩增产物与载体pGM-T连接,转化大肠杆菌DH5α,筛选阳性克隆,测序。结果表明,已成功克隆的阳性重组子经测序鉴定其片段大小与预期大小完全一致,为264 bp。序列同源性分析比较表明,该cDNA及其推导的氨基酸序列与绵羊GDF-9cDNA和氨基酸序列同源性分别为97%和94%。以-βactin为内参照物,采用RT-PCR技术进行半定量分析,通过检测比较牛GDF-9基因在卵巢、输卵管、子宫、肾脏组织中mRNA的表达情况。结果表明,牛GDF-9基因在卵巢中表达量最高,在输卵管、子宫、肾脏中均有表达,但表达量不高。  相似文献   
66.
A reconnaissance survey was made of trace metals in surface waters and three aquatic bryophytes (Scapania undulata,Hygrohypnum luridum andPolytrichum commune) in the mid-Wales Ag-Pb mining district. This area is contaminated by heavy metals from past mining. Elevated levels of Ag, Cd, Cu, Pb, and Zn were found in water and plant tissue. All the plants accumulated Ag and the other metals butScapania appears the most suitable as a plant monitor of Ag-polluted waters.  相似文献   
67.
68.
In vitro PA28 binds and activates proteasomes. It is shown here that mice with a disrupted PA28b gene lack PA28a and PA28b polypeptides, demonstrating that PA28 functions as a hetero-oligomer in vivo. Processing of antigenic epitopes derived from exogenous or endogenous antigens is altered in PA28-/- mice. Cytotoxic T lymphocyte responses are impaired, and assembly of immunoproteasomes is greatly inhibited in mice lacking PA28. These results show that PA28 is necessary for immunoproteasome assembly and is required for efficient antigen processing, thus demonstrating the importance of PA28-mediated proteasome function in immune responses.  相似文献   
69.
70.
Barotropic instability waves on a shear interface propagate at the average speed of the water on the two sides. Assuming the instability to be excited by tidal oscillations, the phase speed is the wavelength divided by the tidal period. If the water is at rest on one side of the shear layer the current speed on the other side can be calculated. This method, applied to the Gulf Stream beyond Cape Hatteras as seen in satellite images, gives estimates of current speed in general agreement with in situ observations.  相似文献   
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