首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   129篇
  免费   24篇
  国内免费   2篇
  2024年   1篇
  2023年   5篇
  2022年   10篇
  2021年   5篇
  2020年   15篇
  2019年   5篇
  2018年   6篇
  2017年   5篇
  2016年   6篇
  2015年   6篇
  2014年   16篇
  2013年   9篇
  2012年   6篇
  2011年   11篇
  2010年   6篇
  2009年   3篇
  2008年   4篇
  2007年   2篇
  2006年   4篇
  2005年   3篇
  2004年   5篇
  2002年   3篇
  2001年   1篇
  1999年   2篇
  1998年   2篇
  1997年   1篇
  1996年   3篇
  1995年   1篇
  1994年   2篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1984年   1篇
  1980年   1篇
排序方式: 共有155条查询结果,搜索用时 31 毫秒
81.
本文研究了宁夏汉族男性不育患者指长波动性不对称(FA)与不育的相关性。分析了宁夏汉族男性不育患者308例(原发组196例, 继发组112例)各指指长FA(2FA、3FA、4FA、5FA)及复合FA(CFA)的均值及其均值的差异性; 比较了指长FA与a+b级精子比率间的关系。结果表明: 1)原发组各指指长FA均值均高于继发组, 且2FA(P<0.01)、4FA(P<0.05)和CFA(P<0.05)有显著性差异; 2)原发组a+b级精子比率显著低于继发组(P<0.05); 3)原发组2FA分布在|L-R|≥0.04组显著增高(P<0.05), 2FA与a+b级精子比率呈高度负相关(P<0.001)。  相似文献   
82.
Ubiquitin-specific protease 9, Y-linked (USP9Y), is a protein encoded by the Y chromosome. Its precise function in the cell is unknown, although a role in the regulation of protein turnover has been postulated. Nonetheless, mutations in this gene could result in the over- or under-abundance of proteins involved in the regulation of spermatogenesis. We have identified a novel mutation, SM1, located in exon 25 of USP9Y (c.3642G→A), which results in an amino acid substitution (p.V1214I). The mutation is in close linkage (four bases distant) from a silent mutation, referred to as M222 (p.E1212E, c.3636G→A). In our male population (n = 374), SM1 was found in one individual (0.3%) who belongs to the recently described haplogroup R1b3h, defined by the U152 SNP. This new mutation is expected to represent a new haplogroup, (R1b1c10a); therefore, within our population of individuals from haplogroup R1b3h (R1b110) (n = 16), it has a frequency of 6.3% (95% CI: 2.7–9.9%).  相似文献   
83.
Targeted deletion of Tssk1 and 2 resulted in male chimeras which produced sperm/spermatogenic cells bearing the mutant allele, however this allele was never transmitted to offspring, indicating infertility due to haploinsufficiency. Morphological defects in chimeras included failure to form elongated spermatids, apoptosis of spermatocytes and spermatids, and the appearance of numerous round cells in the epididymal lumen. Characterization of TSSK2 and its interactions with the substrate, TSKS, were further investigated in human and mouse. The presence of both kinase and substrate in the testis was confirmed, while persistence of both proteins in spermatozoa was revealed for the first time. In vivo binding interactions between TSSK2 and TSKS were established through co-immunoprecipitation of TSSK2/TSKS complexes from both human sperm and mouse testis extracts. A role for the human TSKS N-terminus in enzyme binding was defined by deletion mapping. TSKS immunoprecipitated from both mouse testis and human sperm extracts was actively phosphorylated. Ser281 was identified as a phosphorylation site in mouse TSKS. These results confirm both TSSK 2 and TSKS persist in sperm, define the critical role of TSKS' N-terminus in enzyme interaction, identify Ser 281 as a TSKS phosphorylation site and indicate an indispensable role for TSSK 1 and 2 in spermiogenesis.  相似文献   
84.
目的:探讨输卵管炎性不孕症通水试验的诊断及治疗的临床意义。方法:回顾分析对268例输卵管炎性不孕患者行输卵管通水术后的疗效。结果:来我院进行通水试验治疗的268例输卵管炎性不孕症患者,其中原发性不孕症67例,占发病总数的25%;继发性不孕201例,占75%。经通水反复局部药物治疗,严重者加全身治疗后,输卵管完全通畅者244例,成功率91.04%,术后随访宫内妊娠238例,有效治愈率达88.81%;发生异位妊娠3例,占1.12%。仅有24例经通水治疗无效后行输卵管碘油造影,术后宫内妊娠4例。输卵管通水治疗当月受孕占14.2%。结论:输卵管通水术是诊断和治疗输卵管炎性不孕症的有效方法,早期性生活是否有利于输卵管功能的恢复,有待进一步探讨。  相似文献   
85.
目的:研究阴道超声监测卵泡发育及子宫内膜厚度变化对治疗不孕症妇女的临床价值。方法:选取从2015年4月至2016年9月于我院收治的71例不孕症患者记为观察组。另取同期正常体检者71例记为对照组。分别采用阴道超声对两的卵泡发育以及子宫内膜厚度情况进行监测,观察两组卵泡成熟情况、子宫内膜厚度变化。结果:观察组卵泡成熟占比显著低于对照组,而无卵泡发育占比显著高于对照组,差异均有统计学意义(均P0.05)。观察组子宫内膜三线型人数占比显著低于对照组,而均质型人数占比显著高于对照组,差异均有统计学意义(均P0.05)。观察组排卵前卵泡直径与子宫内膜厚度均显著低于对照组,差异均有统计学意义(均P0.05)。结论:阴道超声监测卵泡发育及子宫内膜厚度变化对不孕症的临床诊断以及治疗均有重要的临床价值。  相似文献   
86.
不育症精子乳酸脱氢酶同功酶LDHx活性测定及其定位研究   总被引:8,自引:0,他引:8  
采用聚丙烯酰胺凝胶电泳、酶联染色、光密度扫描、分光光度法以及电镜酶细胞化学等方法 ,对 12例生育男性(生育组 )和 14例不育男性 (不育组 )精子 L DHx进行了研究。结果显示 L DHx电泳区带位于 L DH3和 L DH4之间 ,生育组精子 L DHx绝对活性和相对活性均高于不育组 (P<0 .0 5 )。相关分析表明精子密度与 L DHx绝对活性和相对活性均具有相关性 ,在生育组呈正相关 (r=0 .8和 0 .75 ,P<0 .0 5 ) ,在不育组呈负相关 (r=- 0 .76和 - 0 .78,P<0 .0 5 )。 L DHx酶细胞化学定位分析显示 L DHx酶反应颗粒主要分布于精子型线粒体 (STM)和胞质内 ,少量分布于顶体及质膜表面。生育组精子各部位酶反应颗粒多于不育组 ,且不育组精子多有畸形并伴有超微结构改变。上述研究分析提示 ,精子 L DHx活性测定与定位分析可作为检查不育症精子质量的可靠指标 ,为男性不育症的临床诊断提供实验依据  相似文献   
87.
ADF/cofilin and actin dynamics in disease   总被引:13,自引:0,他引:13  
ADF/cofilins are key regulators of actin dynamics in normal cells. Recent findings suggest that, under cellular stress, the wild-type proteins might form complexes with actin that can alter cell function. Owing to their rapid formation, these complexes might initiate or aid in the progression of diseases as diverse as Alzheimer's disease and ischemic kidney disease. Although evidence for their involvement in diseases other than Alzheimer's and ischemic kidney disease is tenuous, recent studies suggest that altered production, regulation or localization of these proteins might lead to cognitive impairment, inflammation, infertility, immune deficiencies and other pathophysiological defects.  相似文献   
88.
The human Y chromosome is replete with amplicons-very large, nearly identical repeats-which render it susceptible to interstitial deletions that often cause spermatogenic failure. Here we describe a recurrent, 1.8-Mb deletion that removes half of the azoospermia factor c (AZFc) region, including 12 members of eight testis-specific gene families. We show that this "b2/b3" deletion arose at least four times in human history-likely on inverted variants of the AZFc region that we find exist as common polymorphisms. We observed the b2/b3 deletion primarily in one family of closely related Y chromosomes-branch N in the Y-chromosome genealogy-in which all chromosomes carried the deletion. This branch is known to be widely distributed in northern Eurasia, accounts for the majority of Y chromosomes in some populations, and appears to be several thousand years old. The population-genetic success of the b2/b3 deletion is surprising, (i) because it removes half of AZFc and (ii) because the gr/gr deletion, which removes a similar set of testis-specific genes, predisposes to spermatogenic failure. Our present findings suggest either that the b2/b3 deletion has at most a modest effect on fitness or that, within branch N, its effect has been counterbalanced by another genetic, possibly Y-linked, factor.  相似文献   
89.
Unexplained infertility affects about one-third of infertile couples and is defined as the failure to identify the cause of infertility despite extensive evaluation of the male and female partners. Therefore, there is a need for a multiparametric approach to study sperm function. Recently, we developed a Fluorescence-Based Ratiometric Analysis of Sperm Centrioles (FRAC) assay to determine sperm centriole quality. Here, we perform a pilot study of sperm from 10 fertile men and 10 men in couples with unexplained infertility, using three centriolar biomarkers measured at three sperm locations from two sperm fractions, representing high and low sperm quality. We found that FRAC can identify men from couples with unexplained infertility as the likely source of infertility. Higher quality fractions from 10 fertile individuals were the reference population. All 180 studied FRAC values in the 10 fertile individuals fell within the reference population range. Eleven of the 180 studied FRAC values in the 10 infertile patients were outliers beyond the 95% confidence intervals (P = 0.0008). Three men with unexplained infertility had outlier FRAC values in their higher quality sperm fraction, while four had outlier FRAC values in their lower quality sperm fraction (3/10 and 4/10, P = 0.060 and P = 0.025, respectively), suggesting that these four individuals are infertile due, in part, to centriolar defects. We propose that a larger scale study should be performed to determine the ability of FRAC to identify male factor infertility and its potential contribution to sperm multiparametric analysis.  相似文献   
90.
Seminal plasma is a mixture of secretions from several male accessory glands. The seminal plasma contains many secreted proteins which are important for sperm function and male fertility. In this study, we employed N‐linked glycosylated peptide enrichment, combined with LC–MS/MS analysis, and establish the first large scale N‐linked glycoproteome of human seminal plasma. Combined with the results of five biological replicates, a total of 720 N‐glycosylated sites on 372 proteins were identified. Analysis of variations among five individuals revealed similar compositions of N‐glycosylated proteins in seminal plasma. The N‐linked glycoproteome could help us understanding the biological functions of human seminal plasma. The data set could also be a resource for further screening of biomarkers for male diseases including cancer and infertility at the level of N‐glycosylation. For example, N‐glycosylated prostate‐specific antigen is known to be an efficient biomarker that can distinguish benign prostate hyperplasia from prostate cancer. All MS data have been deposited in the ProteomeXchange with identifier PXD000959 ( http://proteomecentral.proteomexchange.org/dataset/PXD000959 ).  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号