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Initial analytic quality assessment and method comparison of an immunoassay for adrenocorticotropic hormone measurement in equine samples 下载免费PDF全文
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[目的]新鲜精液在离开生殖腺后存活时间很短.相关研究表明副睾液为精子的存活提供了特殊的环境.试验探讨和研究牛附睾精子在体外模拟附睾液中的存活试验的各因素的影响.[方法]试验对公牛附睾头部和尾部的摩尔渗透压和蛋白质浓度进行了分析,牛附睾尾部精子在不同蛋白浓度的CEP-2溶液中,在4℃条件下孵育120h.每24h做一次精子活力检测.[结果]5 d后精子活力仍然超过60;.附睾头、尾部的渗透压分别为(287.0±13.7)mOsm和(310.8±17.0)mOsm.蛋白浓度分别为(37.43±12.55)mg/mL和(50.58±11.08)mg/mL.[结论]附睾尾精子在蛋白浓度为40mg/mL,渗透压为345 mOsm时,精子存活率最高. 相似文献
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DNA methylation is an epigenetic modification in which a methyl group is added usually to the fifth carbon position of a cytosine residue. Dysregulation of this process is an important molecular event which has been shown to be associated with neoplastic transformation and tumour progression in humans and mice. Features of methylation dysregulation in many different types of neoplasms include general genomic hypomethylation, focal hypermethylation, and altered expression of genes which encode a series of DNA (cytosine-5) methyltransferases. Interestingly, many types of neoplasia that are recognised in humans also develop spontaneously in the dog. By comparing the restriction patterns of MspI and HpaII, this study demonstrates that as in human, genomic hypomethylation is a feature of neoplastic cells in the majority of canine lymphoma cases and approximately one-third of canine leukemia cases confirming that dysregulation of the DNA methylating machinery is implicated in malignant transformation of lymphoid cells in some dogs. 相似文献
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AIM: To describe the gross and histological lesions of a neurological disease in Borderdale sheep characterised clinically by blindness and circling, as a basis to its classification. METHODS: Formalin-fixed tissues were processed into paraffin wax and epoxy resin for light and electron microscopy of variously stained sections. RESULTS: Lesions were those of a lysosomal storage disease with severe neurodegeneration of the cerebral cortex. The staining reactions, autofluorescence and ultrastructure of storage material allowed the diagnosis of neuronal ceroid-lipofuscinosis associated with the accumulation of subunit-c of mitochondrial ATP synthase. CONCLUSIONS: The severity of neurodegeneration and minor differences in the ultrastructure of storage material implied that this was a different disease from other forms of ovine ceroid-lipofuscinosis that accumulate subunit-c of mitochondrial ATP synthase. An autosomal recessive mode of inheritance is considered probable. Although of only minor economic importance, this disease may be important to research into the group of ceroid-lipofuscinoses as a whole. 相似文献
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Information is lacking as to the timing and cause of sows that repeatedly have low litter size over several parities. Sows evaluated for the present study had at least two parities either small or=12 (NL) litter size. Following breeding of sows with contemporary boars, reproductive tracts were obtained on day 30 of gestation. There was no difference (p > 0.10) between SL and NL sows in the number of CL, embryo weight or placental length. The total number of embryos and embryonic survival tended to be lower (p < 0.10) in SL sows compared with NL sows, but there were 5.1 less viable embryos (p < 0.03) in SL. Results indicate that time of conceptus loss in SL sows was variable throughout gestation. 相似文献
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