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1.
目的筛选藏绵羊血红蛋白基因和EPAS1基因的低氧正选择位点,并解析位点遗传效应,揭示两基因在藏绵羊低氧适应中的作用。方法以血红蛋白、EPAS1为候选基因,筛选藏绵羊的优势SNP位点,并扩大样本检测3个海拔梯度(1 500、2 500和3 500 m)绵羊的海拔趋势位点和血液生理指标,进行基因型与血液生理指标关联分析。结果藏绵羊血红蛋白、EPAS1基因分别检测到6个和12个SNPs。血红蛋白6个SNPs均为同义突变,其基因频率均未呈现海拔趋势。EPAS1基因第8内含子C871T位点突变等位基因(T)频率呈现明显海拔趋势,该位点TT基因型具有增加血红蛋白含量(HGB)、红细胞平均血红蛋白含量(MCH)和血液黏稠度的遗传效应(P<0.05);通过转录因子结合位点预测,发现该突变导致 GATA (造血调控因子)结合位点丢失。EPAS1基因第9外显子G1001A为非同义突变VAL352MET,但突变等位基因频率仅为0.34,此位点3种基因型与各血液生理指标之间差异均不显著(P>0.05);通过蛋白结构同源预测,未发现蛋白结构功能变化。结论藏绵羊EPAS1基因第8内含子C871T位点突变等位基因(T)的频率随海拔升高而升高,其TT型能显著提高血红蛋白质量浓度14.14 g/L,是藏绵羊高血红蛋白浓度的潜在关联位点。  相似文献   
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目的:探讨夏训对优秀运动员铁调素等铁营养状况以及IL-6的影响。方法:广东省优秀皮划艇运动员26人(男15人,女11人)参加测试,调查夏训前和夏训后血红蛋白、铁调素、可溶性转铁蛋白受体、血清铁蛋白、可溶性转铁蛋白受体/log铁蛋白、血清铁、总铁结合力、转铁蛋白饱和度以及白介素6变化情况。结果:夏训后,男运动员组铁调素和可溶性转铁蛋白受体极显著上升(P<0.01)、血清铁蛋白极显著下降(P<0.01),可溶性转铁蛋白受体/log铁蛋白显著上升(P<0.05),总铁结合力显著下降(P<0.05),白介素6极显著上升(P<0.01)。女运动员组血红蛋白显著降低(P<0.05),铁调素和可溶性转铁蛋白受体极显著上升(P<0.01),血清铁蛋白极显著下降(P<0.01),可溶性转铁蛋白受体/log铁蛋白极显著上升(P<0.01),白介素6极显著上升(P<0.01)。结论:夏训可引起运动员炎症因子升高、铁调素升高,导致功能铁不足;铁调素介导的铁代谢紊乱可能是运动性低血色素发生的重要原因。  相似文献   
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BACKGROUND: Lead is a persistent contaminant in the environment, and waterfowl are susceptible to lead toxicity from ingestion of lead pellets and fishing weights. Lead affects numerous physiologic processes through inhibition of enzyme activity and protein function, but its effects on commonly assessed avian blood values are incompletely understood. OBJECTIVES: Our aim was to evaluate hematologic and biochemical changes associated with blood lead concentrations in trumpeter swans and Canada geese. METHODS: Data for CBCs, plasma biochemical profiles (total protein, albumin, glucose, cholesterol, total bilirubin, calcium, phosphorus, gamma-glutamyltransferase [GGT], aspartate aminotransferase, lactate dehydrogenase, glutamate dehydrogenase, creatine kinase, amylase, and lipase), and whole blood lead concentrations were retrospectively analyzed for 69 trumpeter swans and 52 Canada geese. Laboratory data obtained prospectively from an additional 20 trumpeter swans also were included. RBC morphology was semiquantitated in blood smears from 70 of the birds. Data were analyzed initially by ANOVA and covariance. A statistical model then was constructed to determine the relationship between each parameter and lead concentration. RESULTS: In both avian species, PCV, hemoglobin concentration, and MCHC decreased significantly (P < .05) with increasing blood lead concentration. Uric acid concentration and GGT activity were increased in trumpeter swans and phosphorus concentration was decreased in Canada geese in association with high blood lead concentration (P < .05). CONCLUSIONS: Lead toxicosis induced significant changes in the values of commonly measured hematologic parameters in waterfowl. These changes may be useful indicators of severe lead intoxication during routine laboratory assessment. Changes in clinical chemistry values, although statistically significant, were too inconsistent to serve as indicators of lead toxicosis.  相似文献   
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研究了中药复方Ⅱ对鲤鱼耐缺氧能力和红细胞(RBC)数及血红蛋白(HB)含量的影响。选用体格健康的鲤鱼80尾,平均分成4组,即基础饲料组(对照组)和3个基础饲料加中药组(实验组),后3个实验组设了3个中药添加量。用上述4种饲料对实验鱼饲养120 d后,测定鲤鱼密闭性缺氧浮头时间、红细胞数和血红蛋白含量。结果显示:3个剂量的中药复方Ⅱ实验组能不同程度地延长缺氧条件下鲤鱼浮头时间,增加鲤鱼血液中红细胞数和血红蛋白含量,但低剂量组与对照组相比,差异不显著(P>0.05)。本研究表明中药复方Ⅱ能提高鲤鱼耐缺氧能力,并有改善外周血象的作用。  相似文献   
7.
Hemoglobin (Hb) multiplicity is a commonly used index of phylogenetic differentiation and molecular adaptation in fish. Despite improvements in technologies for characterizing protein structure, our knowledge of the component composition of the Hb system in rainbow trout, Oncorhychus mykiss, has remained almost unchanged through three decades. The Hb is considered to consist of four components, of which two (HbI and HbIV) have been extensively characterised with regard to structure and function. Using a variety of molecular techniques we demonstrate the presence of at least nine different Hb fractions composed of nine (five α and four β globin) chains, and that HbI and HbIV consist of two and five individual components, respectively. These findings indicate that the published data on trout HbI and HbIV refer to mixtures of isoHbs and need to be reappraised. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
8.
本研究将启动子P43与透明颤菌血红蛋白(Vitreoscilla hemoglobin)基因(vgb)通过重叠PCR进行融合,克隆到芽孢杆菌表达载体p CM20上,将筛选得到的重组载体p CM20-vgb转化多粘芽孢杆菌(Paenibacillus polymyxa)NR1,Western-Blot表明重组菌株表达了VHb蛋白,该蛋白的表达对重组菌体的生长和多粘菌素的产生均有促进作用。  相似文献   
9.
Growth of mastitis pathogenic bacteria was measured in bovine whey samples by a turbidometric microtechnique. Whey from mastitis cows supported growth as compared with whey prepared from normal milk. Blood proteins leak into milk during mastitis. A study was undertaken to analyze which molecules from blood would promote bacterial growth in whey Fractions containing hemoglobin showed a distinct growth-promoting effect. An inadequate iron supply is one of the restricting growth factors for bacteria in milk. By utilizing heme-compounds the pathogens can by-pass the effect of antimicrobial iron-binding present in milk in the form of lactoferrin.  相似文献   
10.
用常规方法对同一海拔高度不同发育期牦牛几项指标进行测定。结果:随着牦牛年龄的增长血液中Hb含量、HCT值逐渐增加,而RBC明显降低,差异显著(P<0.05),即随年龄的增长Hb、HCT与RBC的变化呈负相关;心肌和骨骼肌Mb含量随着年龄的增长均呈逐渐递增的趋势,心肌中Mb含量均显著高于骨骼肌,差异显著(P<0.05)。结论:牦牛在生长发育过程中逐渐增加血液中Hb、HCT和骨骼肌、心肌中Mb含量增强机体有氧代谢机制。  相似文献   
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