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61.

Background

The meiotic program initiation pathway genes (CYP26B1, NANOS1 and STRA8) have been proposed to play key roles in spermatogenesis.

Objective

To elucidate the exact role of the genetic variants of the meiosis initiation genes in spermatogenesis, we genotyped the potential functional genetic variants of CYP26B1, NANOS1 and STRA8 genes, and evaluated their effects on spermatogenesis in our study population.

Design, Setting, and Participants

In this study, all subjects were volunteers from the affiliated hospitals of Nanjing Medical University between March 2004 and July 2009 (NJMU Infertile Study). Total 719 idiopathic infertile cases were recruited and divided into three groups according to WHO semen parameters: 201 azoospermia patients (no sperm in the ejaculate even after centrifugation), 155 oligozoospermia patients (sperm counts <20×106/ml) and 363 infertility/normozoospermia subjects (sperm counts >20×106/ml). The control group consisted of 383 subjects with normal semen parameters, all of which had fathered at least one child without assisted reproductive technologies.

Measurements

Eight single nucleotide polymorphisms (SNPs) in CYP26B1, NANOS1 and STRA8 genes were determined by TaqMan allelic discrimination assay in 719 idiopathic infertile men and 383 healthy controls.

Results and Limitations

The genetic variant rs10269148 of STRA8 gene showed higher risk of spermatogenic impairment in the groups of abnormospermia (including azoospermia subgroup and oligozoospermia subgroup) and azoospermia than the controls with odds ratios and 95% confidence intervals of 2.52 (1.29–4.94) and 2.92 (1.41–6.06), respectively (P = 0.006, 0.002 respective). Notably, larger sample size studies and in vivo or in vitro functional studies are needed to substantiate the biological roles of these variants.

Conclusions

Our results provided epidemiological evidence supporting the involvement of genetic polymorphisms of the meiotic program initiation genes in modifying the risk of azoospermia and oligozoospermia in a Han-Chinese population.  相似文献   
62.
63.
目的:探寻军医大学学员内隐层面对自我和他人坚毅性评价的特点及脑电特征,为全面、客观的评估个体的坚毅性提供理论依据和客观指标。方法:使用E-Prime2.0参照经典内隐联想范式编制内隐联想-坚毅测验,对100名军医大学学员施测坚毅量表(Grit O),选取高、低坚毅水平被试(各20名)进行内隐联想-坚毅测验,并记录脑电,分析两组被试的内隐效应及主要脑电成分。结果:计算内隐效应D值,t检验显示高坚毅组(0.55±0.36)显著低于低坚毅组(0.87±0.49),t=-2.257,P0.05,Cohen'd=0.74。两组被试均诱发明显的N400和LPP,高坚毅组中N400在任务状态下主效应显著,F(1,17)=8.528,P0.05,η2=0.334,且在电极位置上主效应显著,F(10,170)=8.207,P0.001,η2=0.326。LPP在任务状态下主效应显著,F(1,17)=5.471,P0.05,η2=0.243,且在电极位置上主效应显著,F(10,170)=18.479,P0.001,η2=0.521;低坚毅组中N400在任务状态下主效应显著,F(1,17)=10.051,P0.05,η2=0.372,且在电极位置上主效应显著,F(10,170)=8.223,P0.001,η2=0.326,LPP在任务状态下主效应不显著。结论:1.军医大学学员坚毅性评价的内隐效应显著,即均倾向于认为自我的坚毅性高,他人的坚毅性低,通过问卷法评估坚毅性时应考虑坚毅评价的内隐效应。2.高、低坚毅性军医大学学员坚毅性内隐评价时的主要脑电成分N400、LPP存在差异,N400可作为坚毅性内隐评价符合程度的判断指标。3.内隐效应及N400可以作为对军医大学学员坚毅性评价时的客观指标。  相似文献   
64.
A structurally simple molecular 1,10‐phenanthroline‐Cu complex on a mesostructured graphene matrix that can be active and selective toward CO2 reduction over H2 evolution in an aqueous solution is reported. The active sites consist of Cu(I) center in a distorted trigonal bipyramidal geometry, which enables the adsorption of CO2 with η1‐COO‐like configuration to commence the catalysis, with a turnover frequency of ≈45 s?1 at ?1 V versus reversible hydrogen electrode. Using in situ infrared spectroelectrochemical investigation, it is demonstrated that the Cu complex can be reversibly heterogenized near the graphene surface via potential control. An increase of electron density in the complex is observed as a result of the interaction from the electric field, which further tunes the electron distribution in the neighboring CO2. It is also found that the mesostructure of graphene matrix favored CO2 reduction on the Cu center over hydrogen evolution by limiting mass transport from the bulk solution to the electrode surface.  相似文献   
65.
玉米花粉单倍体植株染色体上异染色质的变异   总被引:3,自引:1,他引:3  
谷明光  林侠 《遗传学报》1991,18(3):235-238
我们用Giemsa BSG C-带技术检查了玉米花药培养获得的花粉单倍体植株根尖细胞染色体上异染色质的变异,观察结果表明,有的植株所显示的C-带数目是与供体植株的相一致,有的植株所显示的C-带数目则发生了显著变化,其中有的增加,有的减少。并讨论了异染色质发生变异的可能原因。还相应地观察到间期核中染色中心的变化是与中期染色体上C-带数目的变化相一致。  相似文献   
66.
目的:探讨基质金属蛋白酶-7(MMP-7)及其组织抑制剂-1(TIMP-1)与胃癌发生发展的关系.方法:采用免疫组化技术检测46例胃癌组织和相应癌旁组织中MMP-7和TIMP-1的表达,结合病人临床病理资料进行综合分析.结果:胃癌组织中MMP-7阳性表达率(60.87%)显著高于相应癌旁组织,差异有统计学意义(P<0.05);其表达与淋巴结转移(P<0.05)相关.胃癌组织中TIMP-1的阳性表达率(93.48%)明显高于相应癌旁组织(63.04%),差异有统计学意义(P<0.05);其表达与淋巴结转移相关(P<0.05).结论:MMP-7与胃癌的侵袭转移有关,TIMP-1有可能成为评价胃癌恶性生物学行为的指标.  相似文献   
67.
4种杀虫剂对胡瓜钝绥螨成螨的急性毒性   总被引:1,自引:0,他引:1  
测定了4种常用杀虫剂针对目标害虫推荐使用浓度范围对天敌胡瓜钝绥螨Neoseiulus cucumeris成螨的毒力测定、综合急性毒性和二次中毒毒性.综合急性毒性和二次中毒毒性测定结果显示,毒死蜱Chlorphifos、灭幼脲Chlorbenzurin、吡虫啉Imidacloprid对胡瓜钝绥螨都具有极强的毒性,可造成毁灭性杀伤,苏云金杆菌Bt对胡瓜钝绥螨影响极小,无明显毒性.玻片浸渍法测定的不同杀虫剂对胡瓜钝绥螨的毒力大小依次为:毒死蜱Chlorphifos(乐斯本)>灭幼脲Chlorbenzurin>吡虫啉Imidacloprid>苏云金杆菌Bt.  相似文献   
68.
To understand the effects of a novel butyrolactone derivative, 3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2(3H)-one (3BDO), on the apoptosis of vascular endothelial cells (VECs), we exposed 3BDO (20-60 microg/ml) to VECs deprived of serum and FGF-2 for 24 and 48 h, respectively. The results showed that 3BDO (20-60 microg/ml) increased VEC viability and inhibited VEC apoptosis induced by deprivation of serum and FGF-2 in a very weak dose-dependent manner. During this process, integrin beta4 expression was depressed, but the level of reactive oxygen species (ROS) was not changed. The data suggested that 3BDO (20-60 microg/ml) could inhibit VEC apoptosis and suppress integrin beta4 expression, but it could not depress the ROS level induced by deprivation of serum and FGF-2.  相似文献   
69.
遗传标记及其在作物品种鉴定中的应用   总被引:7,自引:0,他引:7  
本文评述了用于作物品种鉴定的形态标记(morphological markers)、细胞标记(cytological markers)、生化标记(biochemical markers)、分子标记(molecular markers)的优缺点。重点评述了分子标记在作物品种鉴定中的应用。文中除对蛋白质电泳指纹图谱——同工酶和贮藏蛋白(包括醇溶性蛋白、清蛋白、谷蛋白、球蛋白等)电泳产生的指纹图谱的应用外,较详细地介绍了近年来DNA指纹图谱技术;包括限制片段长度多态性(restriction fragment length polymorphism,简称RFLP)、随机扩增多态性DNA (random amplified po lymorphic DNA,简称RAPD)、小卫星DNA(minisatellite DNA)、微卫星DNA(microsatellite DNA),简单重复序列间扩增(intersimple sequence repeats,简称ISSR),扩增片段长度多态性(amplified fragment length polymorphism,简称AFLP)以及CAPS (cleaved amplified polymorphic sequences)和SNPS (single nucleotide polymorphisms)对作物品种鉴定和新品种登记,品种纯度和真实性的检验以及品种间亲缘关系的探讨和在分类研究中的贡献等。  相似文献   
70.
The carbohydrate of Gal-alpha1,3-Gal is thought to be the major antigenic epitope present on pig vascular endothelium. The peptides that mimic the binding of antigenic epitope (Gal-alpha1,3-Gal) to lectin BS-I-B4 were identified from screening a filamentous phage-displayed random library. A phage bearing the peptide NCVSPYWCEPLAPSARA has been identified to bind the lectin strongly. Melibiose was able to inhibit the binding of the human natural anti-alpha Gal antibody to the peptide competitively. Our experiments show that the peptide mimetic of Gal-alpha1,3-Gal is able to inhibit the agglutination of pig RBCs by human natural antibody or lectin BS-I-B4. The peptide inhibitor of human natural antibodies may prove useful in pig-to-human xenotransplantation.  相似文献   
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