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101.
102.
肠道病毒71型作为引起儿童群体常见传染性手足口病(HFMD)的主要病原,具有导致少量感染个体出现脑炎等神经系统病变以及相关心肺功能衰竭的病理学特性.因此其预防性疫苗的研发具有重要的公共卫生意义.在前期工作的基础上,一种EV71灭活病毒疫苗(人二倍体细胞)在本研究中基于恒河猴婴猴模型进行了相应的免疫保护性分析.以160EU剂量对2~3月龄婴猴进行0,4周免疫后,动物在第4周接受了剂量为10。~CCID50的病毒经呼吸道的攻击.对病毒攻击后动物在14天内的临床症状、血液生物学、器官病原学分布以及病理学检测的动态观察表明,经疫苗免疫的动物未出现对照动物所具有的特征性临床表现,其血液生物学及病理学检测均无异常.同时,器官病原学分布亦呈阴性.结合动物中和抗体的明确增长及对照动物的综合表现分析,本文的工作证实了该EV71灭活病毒疫苗(人二倍体细胞)在恒河猴婴猴体内的免疫保护性.  相似文献   
103.

Background

Transmitted drug resistance (TDR) remains an important concern for the management of HIV infection, especially in countries that have recently scaled-up antiretroviral treatment (ART) access.

Methodology/Principal Findings

We designed a study to assess HIV diversity and transmitted drug resistance (TDR) prevalence and trends in Mexico. 1655 ART-naïve patients from 12 Mexican states were enrolled from 2005 to 2010. TDR was assessed from plasma HIV pol sequences using Stanford scores and the WHO TDR surveillance mutation list. TDR prevalence fluctuations over back-projected dates of infection were tested. HIV subtype B was highly prevalent in Mexico (99.9%). TDR prevalence (Stanford score>15) in the country for the study period was 7.4% (95% CI, 6.2∶8.8) and 6.8% (95% CI, 5.7∶8.2) based on the WHO TDR surveillance mutation list. NRTI TDR was the highest (4.2%), followed by NNRTI (2.5%) and PI (1.7%) TDR. Increasing trends for NNRTI (p = 0.0456) and PI (p = 0.0061) major TDR mutations were observed at the national level. Clustering of viruses containing minor TDR mutations was observed with some apparent transmission pairs and geographical effects.

Conclusions

TDR prevalence in Mexico remains at the intermediate level and is slightly lower than that observed in industrialized countries. Whether regional variations in TDR trends are associated with differences in antiretroviral drug usage/ART efficacy or with local features of viral evolution remains to be further addressed.  相似文献   
104.
Coronary artery disease (CAD) and its most important complication, myocardial infarction (MI), are the leading cause of premature death in the Western world. CAD has a substantial genetic basis, especially when it occurs early. We investigated the genetic determinants of premature CAD by performing a genomewide linkage analysis of 4,175 affected subjects from 1,933 families recruited throughout the United Kingdom. Each family had at least two available siblings with CAD, with validated onset before age 66 years. Linkage analysis was performed using 416 microsatellite markers. We observed suggestive linkage, for both CAD and MI, to a region on chromosome 2. For CAD, a LOD score of 1.86 was observed at marker D2S2271, which, in an ordered subset analysis, increased to 2.70 in families (n=1,698) with a minimum age at diagnosis of 56 years or younger. For MI, an overlapping peak with a LOD score of 1.15 was observed at marker D2S2216, which increased to 2.1 in families (n=801) with a minimum age at diagnosis of 59 years or younger. Exclusion mapping showed that 100% of the autosomal genome could be excluded for locus-specific sibling relative risks of 1.5 and 1.6 for CAD and MI, respectively. The region identified on chromosome 2 overlaps linked regions observed in two other smaller genome scans for CAD. Together, these findings strongly suggest that there is a locus on chromosome 2 that influences coronary atherosclerosis risk. The exclusion of a common locus that increases risk of CAD to siblings by >50% has important implications for strategies for further defining the genetic basis of CAD.  相似文献   
105.
在 83K 和 160K 两个温度下,通过激发波长对荧光发射谱的影响研究了光系统II中核心复合物的荧光光谱特性。用不同波长的光激发,核心复合物的发射谱的最大发射峰值不变,用 480、489、495 和 507nm 的光分别激发核心复合物,其光谱最大峰值处的荧光强度随不同激发波长下β-胡萝卜素分子的吸收强度的增大而降低,在长波长区域光谱的变化依赖于首先被激发的色素分子。所以,激发波长的不同影响着核心复合物中能量传递的途径。通过高斯解析,分析出核心复合物中至少存在有 7组叶绿素a组分,它们是Chla660,Chla670,Chla680,Chla682,Chla684,Chla687和Chla690。  相似文献   
106.
Although human plasma represents an attractive sample for disease biomarker discovery, the extreme complexity and large dynamic range in protein concentrations present significant challenges for characterization, candidate biomarker discovery, and validation. Herein we describe a strategy that combines immunoaffinity subtraction and subsequent chemical fractionation based on cysteinyl peptide and N-glycopeptide captures with two-dimensional LC-MS/MS to increase the dynamic range of analysis for plasma. Application of this "divide-and-conquer" strategy to trauma patient plasma significantly improved the overall dynamic range of detection and resulted in confident identification of 22,267 unique peptides from four different peptide populations (cysteinyl peptides, non-cysteinyl peptides, N-glycopeptides, and non-glycopeptides) that covered 3,654 different proteins with 1,494 proteins identified by multiple peptides. Numerous low abundance proteins were identified, exemplified by 78 "classic" cytokines and cytokine receptors and by 136 human cell differentiation molecules. Additionally a total of 2,910 different N-glycopeptides that correspond to 662 N-glycoproteins and 1,553 N-glycosylation sites were identified. A panel of the proteins identified in this study is known to be involved in inflammation and immune responses. This study established an extensive reference protein database for trauma patients that provides a foundation for future high throughput quantitative plasma proteomic studies designed to elucidate the mechanisms that underlie systemic inflammatory responses.  相似文献   
107.
108.
匙叶茅膏菜的组织培养与快速繁殖   总被引:1,自引:0,他引:1  
1植物名称 匙叶茅营菜(Drosera spathulata Labill.)。 2材料类别 种子、根茎。 3培养条件 种子萌发培养基:(1)1/2MS。分化、增殖培养基:(2)1/2MS+6-BA1.0mg·L^-1(单位下同)+NAA0.1;(3)1/2MS+6-BA1.0+NAA0.3;(4)1/2MS+6-BA3.0+NAA0.1;(5)1/2MS+6-BA3.0+NAA0.3。  相似文献   
109.
硫氧还蛋白是细胞中普遍存在的低分子量蛋白质,为生物体所必需。硫氧还蛋白、硫氧还蛋白还原酶和烟酰胺腺嘌呤二核苷磷酸组成硫氧还蛋白系统,调节细胞的氧化还原状态。硫氧还蛋白不仅维持细胞的氧化还原平衡,还具有抗凋亡及促进细胞增殖等功能。原核细胞的硫氧还蛋白仅含有两个半胱氨酸残基,真核细胞的硫氧还蛋白除了活性中心的两个半胱氨酸残基外,通常还有另外的半胱氨酸残基。这些半胱氨酸残基的共价修饰使硫氧还蛋白具有了更丰富的功能。硫氧还蛋白的共价修饰包括谷胱甘肽化、巯基氧化、亚硝基化和烷基化。  相似文献   
110.
锡林河流域草地灌木化表现为小叶锦鸡儿(Caragana microphylla)种群的扩张。为了研究放牧与小叶锦鸡儿种群扩张的关系, 从小叶锦鸡儿的种子产量和萌发入手, 分析放牧对小叶锦鸡儿生殖的直接影响(即放牧的直接影响)以及不同放牧处理下昆虫种群对小叶锦鸡儿生殖造成的影响(即放牧的间接影响)。通过比较不同处理下小叶锦鸡儿果荚的数量、种子产量以及昆虫对种子的取食, 发现放牧产生的直接影响和间接影响性质不同, 放牧的直接影响是不利于小叶锦鸡儿的繁殖,而其间接影响却对小叶锦鸡儿的繁殖有利, 且这两种影响在很大程度上会互相抵消。根据所得的研究结果可知在停止放牧之后的一段时间内, 小叶锦鸡儿种群扩张的可能性会增加, 因此在草地生态系统管理中应该注意这个问题。  相似文献   
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