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Kalaitzakis E Roubies N Panousis N Pourliotis K Kaldrymidou E Karatzias H 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):835-845
BACKGROUND: Fatty change of the liver (FCL) is very common in dairy cattle periparturiently. Many laboratory methods have been implicated in order to assist the diagnosis. HYPOTHESIS: To investigate whether FCL in dairy cattle could be evaluated by assessment of ornithine carbamoyl transferase (OCT) by means of an assay modified for bovine serum, other enzyme activity, serum bile acids (SBA) concentration, or other biochemical constituents. ANIMALS: A total of 187 dairy cattle were included: 106 were suspected to have liver dysfunction and were examined after referral by veterinarians; 70 were clinically healthy with mild FCL; and 11 were clinically healthy without FCL. METHODS: Blood and liver biopsy samples were obtained after clinical examination. Histologic examination by light microscopy and classification of samples according to the severity of FCL was done, and total lipid and triglyceride concentration was measured. In serum, OCT, aspartate aminotransferase (AST), alanine aminotransferase (ALT), sorbitol dehydrogenase (SDH), glutamate dehydrogenase (GDH), alkaline phosphatase (ALP), and gamma-glutamyltransferase (gamma-GT) activity as well as SBA, glucose, ketones, total bilirubin (tBIL), and nonesterified fatty acids (NEFA) concentration were measured. RESULTS: OCT and AST activity and tBIL concentration correlate well with the degree of FCL. SBA concentration does not contribute well to FCL diagnosis. The majority of FCL cases appeared within the first 21 days-in-milk (DIM). The majority of moderate-to-severe and severe FCL cases arose in the first 7 DIM. CONCLUSIONS AND CLINICAL IMPORTANCE: Except for OCT, AST, and tBIL, none of the biochemical tests used, including SBA, had sufficient discriminatory power to differentiate reliably between mild and severe FCL because of poor sensitivity. A weak correlation between clinical signs and the extent of FCL was evident. 相似文献
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为探讨水牛OCT4基因的表达调控模式,本研究扩增克隆了水牛OCT4基因5'调控序列片段,并设计了-2 571 bp、-2 389 bp、-2 338 bp和-2 191 bp 4个不同长度的调控序列片段,分别构建了EGFP表达报告载体.通过生产转基因猪早期胚胎和转染水牛胎儿成纤维细胞分析了不同长度调控序列片段的转录活性.结果发现,在猪4.5d胚胎中各调控序列均能成功启动下游EGFP表达,但转染水牛胎儿成纤维细胞48 h后均表观察到荧光.QRT-PCR分析显示,-2 571 bp片段在4.5d猪胚胎细胞中的转录活性极显著高于其他调控序列(P＜0.01),-2 389 hp与-2 338 bp之间差异不显著(P＞0.05),二者均极显著高于-2 191 bp(P＜0.01).上述结果表明水牛源OCT4基因5 '调控序列在猪早期胚胎中具有转录活性,且翻译起始位点上游2 191 bp片段足以介导OCT4在多能性细胞中的特异性表达；-2 389～-2 338 bp片段上游的CR4亦参与了猪4.5d胚胎中OCT4基因的转录调控. 相似文献
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Jae Yeon HWANG Kwang-Hwan CHOI Dong-Kyung LEE Seung-Hun KIM Eun Bae KIM Sang-Hwan HYUN Chang-Kyu LEE 《The Journal of reproduction and development》2015,61(6):533-540
X-chromosome inactivation (XCI) is an epigenetic process that equalizes expression of X-borne genes between
male and female eutherians. This process is observed in early eutherian embryo development in a
species-specific manner. Until recently, various pluripotent factors have been suggested to regulate the
process of XCI by repressing XIST expression, which is the master inducer for XCI. Recent
insights into the process and its regulation have been restricted in mouse species despite the evolutionary
diversity of the process and molecular mechanism among the species. OCT4A is one of the
represented pluripotent factors, the gate-keeper for maintaining pluripotency, and an XIST
repressor. Therefore, in here, we examined the relation between OCT4A and X-linked genes in
porcine preimplantation embryos. Three X-linked genes, XIST,
LOC102165544, and RLIM, were selected in present study because their
orthologues have been known to regulate XCI in mice. Expression levels of OCT4A were
positively correlated with XIST and LOC102165544 in female blastocysts.
Furthermore, overexpression of exogenous human OCT4A in cleaved parthenotes generated
blastocysts with increased XIST expression levels. However, increased XIST
expression was not observed when exogenous OCT4A was obtained from early blastocysts. These
results suggest the possibility that OCT4A would be directly or indirectly involved in
XIST expression in earlier stage porcine embryos rather than blastocysts. 相似文献
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循环经济理论在公园选址和设施上的应用——以深圳东部华侨城为例 总被引：1，自引：0，他引：1
循环经济是资源节约型和环境友好型社会的发展模式,也是旅游经济持续、健康发展的必由之路。文章以深圳东部华侨城主题公园为例,介绍并分析了循环经济理论在公园选址和设施上的应用。 相似文献
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[目的] 分析改性黑垆土出现斥水性的条件及其影响因素,为研究气候暖干化背景下当地降雨入渗行为对斥水性的响应问题提供参考。[方法] 试验在黄土旱塬陕西省长武县农田试验场进行。选取玉米地和苜蓿地0—20 cm土壤作为试验对象,对2种作物下的土样设计4水平土壤含水量、3种容重和3水平十八烷基伯胺（OCT）添加量进行组合配制土样,用滴水穿透时间法进行斥水性测试。[结果] 土壤斥水性（SWR）随着土壤含水量（0%～6%范围）和容重的增加及OCT添加量的增加而增大,其中土壤含水量、OCT添加量和土壤容重对SWR的影响存在多因素交互效应。在逐步回归分析中,OCT和含水量共同参与下的拟合模型更优。1.3 g/cm3土壤容重下,在0%含水量和0.15% OCT添加量及2%含水量和0.10% OCT添加量条件时,非斥水的黑垆土土壤会转变为轻微斥水性土壤。[结论] 在黑垆土低水条件下的降水入渗过程中,应更多关注不同土地利用土壤含水量和极性物质的积累变化对斥水风险的影响。 相似文献
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