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111.
采后红毛丹(品种‘粉红’)果实贮于10℃下时呼吸速率下降、细胞膜透性减小、多酚氧化酶活性(PPO)下降、病害少;4℃下贮藏至第4天时即发生冷害;采后用3%抗坏血酸溶液、2%柠檬酸溶液和1%NaCl处理的红毛丹果实中含糖量和果皮花色素苷含量均不减小,其中以10℃下用化学药品处理的效果最显著。  相似文献   
112.
有假说认为,卵母细胞在体外培养过程中,如果延长GV期,可促进卵母细胞进一步成熟,因而提高发育潜能。采用山羊半卵泡和卵母细胞共培养,抑制卵母细胞GVBD发生,从而延长GV期。比较了共培养前后和恢复成熟培养后卵母细胞的超微结构变化,其目的从亚细胞水平寻找卵母细胞进一步成熟的证据。研究发现,常规成熟培养:有卵周隙存在,但不贯通,局部区域卵膜与透明带结合紧密;部分皮质区尚有细胞器存在;微绒毛大部分从透明带中撤出,倒伏于质膜表面,数量较多,形态较为粗大;皮层颗粒质膜下部分单层分布,部分散布于皮质区;线粒体均匀散布于卵质中央区。共培养前:卵母细胞的卵周隙尚未形成,微绒毛没有从透明带中撤出;线粒体等细胞器分布于皮质区,皮层颗粒成簇状分布,皮质区富含细胞器。共培养后:局部形成卵周隙,微绒毛已自透明带中撤出,数量较多,垂直或倒伏于卵膜表面;线粒体以簇状分批开始内移,皮层颗粒已部分单层分布于质膜下,部分皮质区缺乏细胞器。恢复成熟培养后:卵周隙进一步扩大并且贯通,微绒毛数量减少并且绝大多数垂直于卵膜;线粒体在卵质中央区均匀分布,皮层颗粒卵膜下单层分布,大部分皮质区无细胞器存在。利用“两步法”培养得到的卵母细胞与体外常规成熟培养的卵母细胞相比,更有利于皮层颗粒的质膜下单层分布,卵母细胞卵周隙的形成与贯通,微绒毛数量减少和垂直于卵膜表面,无细胞器皮层区的进一步形成。因此,更有利于卵母细胞胞质的进一步成熟。  相似文献   
113.
体外去除胆固醇菌株的筛选及其作用机理研究   总被引:2,自引:0,他引:2  
从青年人肠道中筛选分离,鉴定得到8株乳杆菌,进行胆固醇去除、耐酸和耐胆汁盐实验,发现两株植物乳杆菌Lp529和Lp501同时具有较高的体外去除胆固醇能力和耐胆汁盐及耐酸性能。通过对它们胆固醇去除过程和胆固醇在相应固液相中分布情况的实验分析,表明:Lp501与Lp529去除胆固醇的机理有差别,存在菌株特异性。研究还发现,被菌株吸收的胆同醇没有被代谢为其他物质,并可在条件适合时重新释放出来。  相似文献   
114.
采用解剖学方法,研究了水龙骨科鹿角蕨亚科石韦属(Pyrrosia)17种植物的脉序特征,并与该科其它3亚科8属8个代表种的脉序进行了对比。结果显示,石韦属植物的脉序属于结合脉序,并可进一步细分为弯脉蕨型和拟槲蕨型。根据脉序特征的聚类分析表明,石韦属植物的结合脉序与水龙骨科其它属植物的结合脉序具有显著差异,且此脉序特征是石韦属内较稳定的分类性状,具有一定的分类学价值。本研究还基于脉序特征,讨论了石蕨(P.angustissimum(Giesenh.ex Diels)TagawaK.lwats.)、抱树石韦(P.piloselloides M.G.Price Kalikasan)与其它石韦属植物的亲缘与进化关系。  相似文献   
115.
Tumors originating from ectopic adrenal tissue are relatively rare. In this article, we describe a case with Cushing's syndrome caused by an ectopic adrenal adenoma. A 38 year-old male patient presenting with cushingoid appearance for 2 years was diagnosed to have ACTH-independent Cushing's syndrome based on endocrinological evaluation. Mutiple radiological examinations detected bilateral adrenal atrophy. When the images were investigated in a more expanded scope, a 3.0×3.5×5.3?cm mass was detected in the anterior of left renal hilum and left renal vein. The mass was successfully resected with intraoperative endoscopy and pathological evaluation revealed an ectopic adrenal tumor. It is suggested that when the endocrinlogically confirmed adrenal neoplasm could not be well and definitely localized, the possibility of ectopic adrenal should be presumed and further radiography examinations should extend to the field where ectopic adrenal usually presents.  相似文献   
116.
An apolipoprotein A-I mimetic peptide, D-4F, has been shown to improve vasodilation and inhibit atherosclerosis in hypercholesterolemic low-density lipoprotein receptor-null (LDLr(-/-)) mice. To study the metabolic variations of D-4F ininhibiting atherosclerosis, metabonomics, a novel system biological strategy to investigate the pathogenesis, was developed. Female LDLr(-/-) mice were fed a Western diet and injected with or without D-4F intraperitoneally. Atherosclerotic lesion formation was measured, whereas plasma metabolic profiling was obtained on the basis of ultra-high-performance liquid chromatography in tandem with time-of-flight mass spectrometry operating in both positive and negative ion modes. Data were processed by multivariate statistical analysis to graphically demonstrate metabolic changes. The partial least-squares discriminate analysis model was validated with cross-validation and permutation tests to ensure the model's reliability. D-4F significantly inhibited the formation of atherosclerosis in a time-dependent manner. The metabolic profiling was altered dramatically in hypercholesterolemic LDLr(-/-) mice, and a significant metabolic profiling change in response to D-4F treatment was observed in both positive and negative ion modes. Thirty-six significantly changed metabolites were identified as potential biomarkers. A series of phospholipid metabolites, including lysophosphatidylcholine (LysoPC), lysophosphatidylethanolamine (LysoPE), phosphatidylcholine (PC), phatidylethanolamine (PE), sphingomyelin (SM), and diacylglycerol (DG), particularly the long-chain LysoPC, was elevated dramatically in hypercholesterolemic LDLr(-/-) mice but reduced by D-4F in a time-dependent manner. Quantitative analysis of LysoPC, LysoPE, PC, and DG using HPLC was chosen to validate the variation of these potential biomarkers, and the results were consistent with the metabonomics findings. Our findings demonstrated that D-4F may inhibit atherosclerosis by regulating phospholipid metabolites specifically by decreasing plasma long-chain LysoPC.  相似文献   
117.
118.
ABSTRACT: BACKGROUND: Serum C-reactive protein (CRP) and leptin levels have been independently associated with the cardiovascular risk factors. The aim of the present study was to determine if their serum levels were associated with cardiovascular risk factors or metabolic syndrome as well as their correlation in the Taiwanese population. METHODS: This retrospective study included 999 subjects (> 18 y), who underwent a physical examination in Chang-Gung Memorial Hospital-Linkou and Chiayi in Taiwan. The associations between CRP and/or leptin levels and cardiovascular risk factors and metabolic syndrome were determined using independent two sample t-tests to detect gender differences and chi-square tests to evaluate differences in frequencies. To compare the means of the variables measured among the four groups (high and low leptin and high and low CRP), analysis of variance (ANOVA) was used. RESULTS: Both CRP and leptin levels were independently associated with several cardiovascular risk factors, including diabetes, hypercholesterolemia and metabolic syndrome in both men and women (P < 0.05). In addition, a positive correlation between leptin and CRP levels was observed in both genders. Both high-CRP and high-leptin were associated with high blood glucose, waist circumference and serum triglyceride. Whereas increased metabolic syndrome incidence was observed in males with elevated leptin regardless of CRP levels, females with elevated CRP or leptin had increased incidence of metabolic syndrome. CONCLUSION: Both leptin and CRP levels were associated with cardiovascular risk factors as well as metabolic syndrome score in both men and women although gender-specific differences were observed. Thus, CRP and leptin may represent useful biomarkers for predicting the onset of cardiovascular disease or metabolic syndrome in Taiwanese adults. Trial registration IRB/CGMH 100-3514B.  相似文献   
119.
2009年1月~2010年12月,对牛背梁自然保护区血雉栖息地选择与利用情况进行了调查研究.结果表明,血雉Ithaginis cruentus sinensis David栖息分布于秦岭主脊以南海拔2000~2500 m中山地带、乔木高度较矮(5~10 m)、郁闭度较低(0.3~0.5)、林下灌木稀疏(≤0.2)的针阔混交林中.从地形情况来看,则多活动于山坡的上坡位或梁脊处、坡度相对较为平缓(≤25°)地带的半阴半阳坡.距离水源较远(150 m),对人为干扰的敏感性相对较弱.从对各生态因子的偏好性来看,血雉比较偏好坡度相对较陡(25°~40°)、乔木高度低矮(≤5 m)、郁闭度低(≤0.2)的针叶林,以及盖度在0.3~0.6的竹林、隐蔽性较高(≤5 m)、距离水源较近(50~100 m)的环境,而对其他因子的选择性和偏好性则无差异.主成分分析表明,血雉栖息地选择的主要因子有3种:干扰因子(依次为坡向、植被类型、坡位、乔木高度与人为干扰距离)、隐蔽因子(灌木盖度、竹林盖度、隐蔽性、坡度、乔木郁闭度和水源距离)和食物因子(灌木盖度).人为活动干扰是影响血雉对栖息地各生态因子选择的最根本的诱因.  相似文献   
120.
本研究通过采集1型人类免疫缺陷病毒(Human immunodeficiency virus-1,HIV-1)感染者抗凝全血,分离出外周血单个核细胞,然后用磁珠分选纯化记忆性B细胞和体外活化记忆性B细胞,促使其分泌抗体,用ELISA法识别阳性B细胞克隆,并提取阳性B细胞的RNA,从中扩增抗体重链和轻链基因并克隆到表达载体中,再用携带重链基因的质粒和携带轻链基因的质粒共转染293T细胞,获得HIV-1特异性人单克隆抗体,进行抗体特性的鉴定。结果从1例HIV-1感染者的记忆性B细胞中筛选出了4株HIV-1包膜糖蛋白(Envelope glycoprotein,Env)特异性人单克隆抗体,其中2株具有较好的抗体依赖细胞介导的细胞毒作用活性,另有1株对HIV-1假病毒有较弱的中和活性。说明我们成功地引进了利用B细胞培养和RT-PCR技术从人体淋巴细胞中筛选特异性抗体基因的人单克隆抗体技术平台。用该技术可以成功获得HIV-1Env特异性单克隆抗体,为将来从能产生高滴度广谱中和抗体的感染者体内筛选广谱中和抗体打下了基础。  相似文献   
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