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1.
在研究类固醇激素及其受体的相互作用或不同生理、病理条件下激素受体的特性和数量变化的过程中,经常需要制备受体并建立准确可靠的分析方法,以便得到比较理想的结果。为此,我们以兔子宫为材料,分析了内膜细胞核的雌激素受体。一、制备:将屠宰场取来的兔子宫纵向剪开,用冷生理盐水冲洗,解剖刀刮取内膜,按以往粗核方法得到洗过的沉淀,制成0.4MKCI的悬浮液,取一部分测DNA,  相似文献   
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Signal transduction pathways in guinea pig sperm   总被引:2,自引:0,他引:2  
Trifluoperazine (TFP), the antagonist of calmodulin (CaM). significantly stimulated the capacitation and acrosome reaction of guinea pig spermatozoa at the concentration of 10-100μmol/L, independent of the external Ca2+. Forskolin, dbcAMP and caffeine evidently promoted the occurrence of acrosome reaction of spermatozoa at early capacitation stage (5 h) in nonsynchronous system but not in synchronous system. If the spermatozoa were capacitated for 15 h in synchronous system, the above three drugs significantly stimulated acrosome reaction in a Ca2+-independent manner. Protein kinase C activators, i.e. phorbol 12-myristate 13-acetate (PMA) and phorbol 12,13-dibutyrate (PDB) did not influence the occurrence of acrosome reaction of spermatozoa at early capacitation stage, but significantly increased the acrosome reaction rate in capacitated spermatozoa in a Ca2+-independent manner. In contrast. PKC inhibitor staurosporine significantly inhibited the occurrence of acrosome reaction.  相似文献   
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小鼠附睾头精子获得与卵子质膜融合能力的物质基础研究   总被引:1,自引:0,他引:1  
随着精子在附睾中的转运,它们与卵子质膜的融合能力逐渐增加。怩证明2附睾体和附睾尾的精子均具有相当高的膜融合能力,而附睾头中的精了奶少能与卵子质膜融合,这是还说明附睾头中的精子不具备与云透明带卵子融合的物质条件呢?利用附睾结扎留并延长体外获能时间,可使附睾头远端精子的融合能力明显地提高;在精子培养液中加入ATP,并延长精卵共培养时间,也可使一少部分附睾头近端的精子获得与卵子质膜融合的能力。这表明附睾  相似文献   
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小鼠精子在附睾成熟过程中质膜糖蛋白的变化   总被引:3,自引:0,他引:3  
利用蛋白印迹法研究了小鼠精子在附睾成熟过程中质膜糖蛋白的变化。结果表明:与花生凝集素结合的104kD和95kD糖蛋白,与伴刀豆凝集素结合的117、114、104、87、76、70kD糖蛋白在睾丸中已完成了蛋白合成及修饰过程;与伴刀豆凝集素结合的120kD和65kD糖蛋白,与双花扁豆凝集素结合的54kD糖蛋白在精子附睾成熟过程中被修饰成其它种类的蛋白或被丢失。与伴刀豆凝集素结合的109kD糖蛋白,与  相似文献   
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An antisperm monoclonal antibody 6B10 was produced by hybridoma technique of the isotype IgG. The monoclonal antibody was purified by means of ammonium sulfate precipitation and protein A-Sepharose Cl-4B affinity chromatography. SDS polyacrylamide gel electrophoresis was used to evaluate the purity of the antibody. Evaluation of the sperm acrosomal status was determined by chlortetracycline (CTC) staining. It was found that monoclonal antibody 6B10 can inhibit the sperm acrosome reaction induced by progesterone. The corresponding antigen recognized by monoclonal antibody 6B10 was located on the plasma membrane of the sperm acrosome by indirect immunofluorescent microscopy and immunoelectronmicroscopy. Sperm protein was extracted by 1% Triton X-100. The molecular weight of the antigen is 50 ku, detected by Western blot. The antigen is a key protein in the sperm acrosome reaction and may be the receptor of progesterone on the sperm acrosome. It may either be developed as a candidate contraceptive vaccine  相似文献   
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An anti-mouse spermatozoon monoclonal antibody, MSH27, as well as its purified antigen, can block sperm-egg membrane fusion. As a candidate protein for sperm-egg membrane fusion, the sperm antigen was investigated in the process of post-testicular maturation (PTM). The molecule was produced in testes and located on the plasma membrane of the postacrosomal area of the spermatozoon. However, the epitope recognized by the MSH27 (MSH27Ep) was not exposed until the occurrence of the acrosome reaction. In the process of fertilization, spermatozoa must complete the acrosome reaction before penetrating across the zona pellucidas (ZPs) to approach the plasma membrane of eggs. The effects of the acrosome reaction and penetration of the ZP on the exposure of the MSH27Ep were also studied. It was shown that the percentage of the spermatozoa with the MSH27Ep exposed increased followed with their mature status in PTM. In fact, it bad a linear correlativity with the rate of the acrosome reaction. After spermatozoa had  相似文献   
9.
外源促性腺激素诱导大熊猫发情及人工繁殖获得首次成功   总被引:2,自引:0,他引:2  
目前大熊猫正面临灭绝的危险,只靠野外自然繁殖来延续物种,看来问题越发严重。由于大熊猫生殖机能日趋衰退,依靠它自然发情,本交或人工输精,虽也曾获得过产仔,但机率仍不高。更严重的是由于奶水不足,育幼存活率极低。经过研究,现在已能有效地控制和提高育龄大熊猫的繁殖能力,那就是利用外源激素控制雌性大熊猫发情、排卵和改进精子的稀释液提高精子的活力,改善精卵结合条件,有利受精和胚胎发育。  相似文献   
10.
MSH2 7是一株抗小鼠精子的单克隆抗体 ,此抗体及其纯化的抗原分子在体外受精实验中均可以阻止精卵膜融合 ,因而推测其抗原在精卵膜融合过程中具有重要的作用 .这里探讨了抗原分子在精子睾丸后成熟过程中MSH2 7识别表位的显露条件 .MSH2 7抗原分子在睾丸中产生 ,定位于精子顶体后区的质膜上 ;但MSH2 7所识别的抗原表位只在顶体反应后的精子上表露 .在受精过程中 ,精子必须完成顶体反应并穿过卵子的透明带才能接近卵子质膜并与之融合 .同时还研究了顶体反应和穿透明带作用对MSH2 7表位显露的影响 .在附睾成熟过程中 ,随着精子在附睾中的转运 ,它们发生顶体反应的能力不断增加 ;精子抗原表位的显露呈现顶体反应依赖性 ,且两者呈现线性回归关系 .钙离子载体A2 3 187诱发顶体反应后 ,MSH2 7染色阳性的精子远远少于顶体反应的精子 ;但穿过透明带后绝大多数精子 ( 98% )呈现MSH2 7染色阳性 .总之 ,在睾丸后成熟 (附睾成熟、获能、顶体反应 )和精子穿透明带的过程中 ,对整个精子群体来讲 ,单抗MSH2 7所识别的抗原表位的显露和精子最终获得穿入卵子质膜的能力是同步发生的 .  相似文献   
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