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121.

Background

The impact of viral load (VL) decay and cumulative VL on CD4 recovery and AIDS after highly-active antiretroviral therapy (HAART) is unknown.

Methods and Findings

Three virologic kinetic parameters (first year and overall exponential VL decay constants, and first year VL slope) and cumulative VL during HAART were estimated for 2,278 patients who initiated HAART in the U.S. Military HIV Natural History Study. CD4 and VL trajectories were computed using linear and nonlinear Generalized Estimating Equations models. Multivariate Poisson and linear regression models were used to determine associations of VL parameters with CD4 recovery, adjusted for factors known to correlate with immune recovery. Cumulative VL higher than the sample median was independently associated with an increased risk of AIDS (relative risk 2.38, 95% confidence interval 1.56–3.62, p<0.001). Among patients with VL suppression, first year VL decay and slope were independent predictors of early CD4 recovery (p = 0.001) and overall gain (p<0.05). Despite VL suppression, those with slow decay during the first year of HAART as well as during the entire therapy period (overall), in general, gained less CD4 cells compared to the other subjects (133 vs. 195.4 cells/µL; p = 0.001) even after adjusting for potential confounders.

Conclusions

In a cohort with free access to healthcare, independent of established predictors of AIDS and CD4 recovery during HAART, cumulative VL and virologic decay patterns were associated with AIDS and distinct aspects of CD4 reconstitution.  相似文献   
122.
Bacteriophages are the most numerous biological entities in the biosphere, and although their genetic diversity is high, it remains ill defined. Mycobacteriophages-the viruses of mycobacterial hosts-provide insights into this diversity as well as tools for manipulating Mycobacterium tuberculosis. We report here the complete genome sequences of 138 new mycobacteriophages, which-together with the 83 mycobacteriophages previously reported-represent the largest collection of phages known to infect a single common host, Mycobacterium smegmatis mc(2) 155.  相似文献   
123.
The utility of induced pluripotent stem cells (iPSCs) as models to study diseases and as sources for cell therapy depends on the integrity of their genomes. Despite recent publications of DNA sequence variations in the iPSCs, the true scope of such changes for the entire genome is not clear. Here we report the whole-genome sequencing of three human iPSC lines derived from two cell types of an adult donor by episomal vectors. The vector sequence was undetectable in the deeply sequenced iPSC lines. We identified 1,058-1,808 heterozygous single-nucleotide variants (SNVs), but no copy-number variants, in each iPSC line. Six to twelve of these SNVs were within coding regions in each iPSC line, but ~50% of them are synonymous changes and the remaining are not selectively enriched for known genes associated with cancers. Our data thus suggest that episome-mediated reprogramming is not inherently mutagenic during integration-free iPSC induction.  相似文献   
124.
125.
男性不育与基因缺陷   总被引:2,自引:0,他引:2  
阮健  杜卫东 《遗传》2010,32(5):411-422
目前全世界约有15%的育龄夫妇不育, 其中男性因素占50%。男性不育(Male infertility)病因复杂, 许多内外因素可导致男性不育, 其中生育相关基因缺陷是重要原因之一, 患者临床多表现为无精子症及少弱畸精子症。文章主要论述了已知基因缺陷与男性不育的关系。  相似文献   
126.
瑞拉菌素产生菌S-5120菌株防治黄瓜霜霉病害的研究初报   总被引:6,自引:0,他引:6  
疏秀林  安德荣 《西北植物学报》2004,24(11):2118-2121
经黄瓜霜霉病孢子萌发试验和离体叶片抑菌试验表明,瑞拉菌素产生菌S-5120菌株和瑞拉菌素均对黄瓜霜霉病有较强抑制作用。温室防病试验表明,瑞拉菌素产生菌S-5120发酵液对黄瓜霜霉病有明显的保护和治疗作用。相对保护效果达75.17%;治疗效果达69.69%,且高于农抗-120的相对防效62.65%。  相似文献   
127.
唐古特白刺单果优株果序性状变异研究   总被引:1,自引:0,他引:1  
依据单果大小和口感等指标选择出39个唐古特白刺(Nitraria tangutorum Bobr.)果用优株。并以此为试验材料进一步就果序性状变异进行了研究,结果表明:白刺中选优株的果大小、果重、核果比等单果性状株间差异显著,而株内变异较小。在白刺天然群体内,果序性状差异极为显著,其中不乏果序重突出的单株。中选优株B12、B19等的平均果序重可达8.260g和8.271g,分别比对照高出6.86倍、6.87倍;比39个中选优株的平均值超出1.26倍、1.29倍。尽管白刺株内果序重变幅较大,但B12、B19的果序重最小值仍远远高出对照,甚至分别高出39株平均值79%和66%。由于与果序重密切相关的每序核果数与单果重等单果性状相对独立,因此从果用型白刺开发利用角度考虑,与产量相关更为紧密的果序重应该作为白刺优株选择以及亲本选择的主要依据。  相似文献   
128.
对中国透大叶蝉属Nanatka Young进行了分类概述,确认我国现知9种,其中包括2新种,矛突透大叶蝉N.teluma sp.nov.和渐细透大叶蝉N.attenuata sp.nov..文中给出了该属所有种的检索表。模式标本分别保存于中国科学院动物研究所和西北农林科技大学昆虫博物馆。  相似文献   
129.
山东胜利油田第四系微体浮游藻类及其环境意义   总被引:1,自引:0,他引:1  
对山东胜利油田第四系2个钻孔300余块样品进行了分析,发现沟鞭藻、颗石藻、绿藻和疑源类等微体浮游藻类化石。简要报道了藻类化石的分布情况和组合特征。结合介形虫和有孔虫资料,探讨了该区第四纪沉积环境的变迁,进一步证实该区自中更新世以来发生过4次较大规模的海进海退。  相似文献   
130.
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