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41.
以与东北马鹿物种最近的牛(Bos taurus cattle,序列号为AB076403)的肌肉生长抑制素(myostatin,MSTN)基因序列为模版,根据该基因保守序列进行引物设计,扩增产物连接入pMD18-T载体,克隆出3个外显子片段.根据5′-GU-AG-3′规则和同源基因比对拼接出带有部分5′、3′末端的cDNA,并采用生物信息学技术对编码氨基酸序列进行蛋白质同源性比较和二级、三级结构等分析.结果表明:所获序列全长为1 128 bp,编码375个氨基酸;具有较明显的螺旋、片层和无规卷曲等二级结构;有1个较明显的跨膜区和1个疏水区,并发现明显的信号肽和糖基化位点.三级结构同源建模预测结果显示与Human Activin A的相似性为42%.结果说明东北马鹿和其他哺乳类生物的肌肉生长抑制素基因之间关系密切,并同属于TGF-β家族. 相似文献
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Meiotic Response of In vitro Matured Canine Oocytes under Different Proteins and Heterologous Hormone Supplementation 总被引:2,自引:0,他引:2
The impact of TCM‐199 supplemented with different proteins and heterologous hormones on the in vitro maturation (IVM) rate of bitch oocytes was evaluated by nuclear staining under fluorescence microscopy. Oocytes were recovered by slicing of ovaries from bitches presented at various stages of oestrous cycle to ovariohysterectomy. The basic culture medium was TCM‐199 supplemented with 25 mM Hepes/l, with 10% heat‐inactivated oestrous cow serum (ECS), 50 μg/ml gentamicin, 2.2 mg/ml sodium bicarbonate and 22‐μg/ml pyruvic acid, 1.0‐μg/ml oestradiol (E 8875; Sigma), 0.5‐μg/ml follicle‐stimulating hormone (FSH) (Folltropin‐V; Vetrepharm Inc., Ontario, Canada) and 0.03 IU/ml human gonadotropin (hCG) (Profasi HP; Serono, Aubonne, Switzerland). Oocytes were distributed randomly between basic culture medium (control) and the corresponding experimental treatment. Hormone treatments were: oocytes cultured in; (1) medium without FSH, (2) control medium supplemented with 20 μg/ml oestradiol, or (3) medium supplemented with 1 μg/ml human somatotropin (hST; Humatrope, Lilly, Saint Cloud, France). The second experiment consisted of oocytes cultured in medium supplemented with 0.4% (w/v) bovine serum albumin (BSA, fraction V; Gibco Grand Island, NY, USA) instead of ECS, or oocytes cultured in medium with 10% inactivated oestrous bitch serum (EBS) instead of ECS. Oocytes were cultured in 100 μl droplets (up to 25 oocytes per drop) under mineral oil at 37°C in a 100% humidified atmosphere containing 5% CO2 in air. After 72 h of IVM, the highest rates (p < 0.05) of meiotic resumption were achieved with the 0.4% BSA supplementation. A positive influence on the metaphase II (MII) acquisition rate was observed with hST supplement. Oocytes cultured with 10% EBS supplementation did not develop to the MII stage. The results in this study show that the protein and hormone supplements to TCM‐199 culture medium tested did not promote the final steps of IVM of bitch oocytes. 相似文献
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F. W. K. Smith Jr DVM L. C. Buoen BA A. F. Weber DVM PhD S. D. Johnston DVM PhD J. F. Randolph DVM D. J. Waters DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1989,3(2):90-95
A 6-month-old stunted female Doberman Pinscher was found to have a 77,X0 chromosomal complement. The ovaries were small, consisting primarily of interstitial-type cells and solid epithelial cords. The dam, sire, and a male littermate had normal karyotypes. 相似文献
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Mellor PJ Roulois AJ Day MJ Blacklaws BA Knivett SJ Herrtage ME 《The Journal of small animal practice》2005,46(5):237-242
This report describes the clinical and pathological findings of a suspected idiosyncratic adverse drug reaction in a young dog. The patient presented with sudden onset, severe skin lesions together with episodes of collapse. Investigations revealed a neutrophilic dermatitis with vasculitis, immune-mediated haemolytic anaemia and thrombocytopenia. Similar pathology has been described in human cases of Sweet's syndrome. The chronology of events suggested an adverse drug reaction to carprofen, although two antibiotics had been prescribed within the dog's recent history. Lymphocyte transformation tests were performed and tended to exclude both antibiotics as the cause of the reaction. To the authors' knowledge, lymphocyte transformation tests have not previously been described with regard to drug hypersensitivity assessment in the veterinary literature, and this is the first peer-reviewed case report of neutrophilic dermatitis and vasculitis with immune-mediated haemolytic anaemia and thrombocytopenia occurring as a suspected adverse drug reaction to carprofen in the dog. 相似文献
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Sandra A. Loftus BA Jill M. Montplaisir BS Jing-wen Kuo MS Dale P. DeVore PhD 《Journal of Equine Veterinary Science》1988,8(2)
A standardized investigation was conducted to compare the biophysical properties of hyaluronate products used in the treatment of joint dysfunction in horses. Results showed that two of the five products, Hyvisc® and Hylartin®V, contained higher-weight molecular hyaluronate (greater than 1.5×106). Other investigations have shown that higher molecular weight hyaluronate is effective in providing physical resistance to shear, in stimulating endogenous hyaluronate synthesis, and in inhibiting excess cell proliferation which may be associated with synovial pannus formation. It is suggested that the therapeutic benefits of hyaluronate products may be dependent on the molecular size of the hyaluronate molecules. Higher molecular weight hyaluronate products would be expected to be more effective than lower molecular hyaluronate products in providing therapeutic benefits. 相似文献
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采用荷斯坦奶牛X性控冻精和超数排卵技术结合生产奶牛性控胚胎,以建立高效、低成本的体内性控胚胎生产方法。研究发现,使用CIDR和Cue-Mate进行奶牛同期发情处理,发情率分别为90.9%和100%(P<0.05),且Cue-Mate的发情时间更加集中;加拿大的FOLLTROPIN-V和中国科学院动物研究所的FSH对奶牛超排效果影响不显著,分别为头均胚胎数10.08枚±8.08枚、头均可用胚胎数2.38枚±3.07枚和头均胚胎数6.57枚±4.31枚、头均可用胚胎数2.00枚±1.88枚,无显著差异(P>0.05);奶牛发情后12h~14h和16h~19h人工授精,分别获得头均胚胎数10.25枚±5.53枚、头均可用胚胎数5.33枚±4.52枚和头均胚胎数10.13枚±6.93枚、头均可用胚胎数5.88枚±6.26枚,无显著差异(P>0.05)。但是未受精胚胎数差异显著(27对7,P<0.05)。 相似文献
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羊附红细胞体巢式PCR检测方法的建立及临床应用 总被引:2,自引:1,他引:1
根据GenBank上发表的羊附红细胞体16SrRNA基因序列(登录号AF338268)设计2对引物,用巢式PCR方法扩增16SrRNA的部分序列,将目的片段克隆并测序。测序结果与AF338268相似性达99%以上,只有3bp的差异。该方法与猪附红细胞体、羊肺炎支原体、链球菌、葡萄球菌和大肠杆菌均无交叉反应,能检测到的最低DNA量为25fg。用于检测的28份临床样本中,23份为阳性。所建立的巢式PCR检测方法具有较高的敏感性和特异性,可用于羊附红细胞体病急性感染和隐性感染的早期诊断,为该病的临床检测、流行病学调查、进出口检疫和实验室研究提供了新的技术手段。 相似文献