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991.
目的:制备谷胱甘肽S转移酶(GST)的兔多抗,并鉴定该抗体的特异性。方法:用纯化的GST标签蛋白(纯度>98%)免疫新西兰大白兔,获得GST的兔抗血清,并经HiTrap rProtein A柱纯化获得高效价高特异性的抗体;用间接ELISA法检测抗体效价,Western印迹检测抗体的特异性,并与商业化抗体进行对比。结果:通过免疫法得到了GST的兔多克隆抗体血清,抗体效价达1∶1×106,经rProtein A柱纯化后获得了高效价高特异性的抗体,其高效高特异性已达商业化抗体水平。结论:获得了GST的高效价高特异性的兔多克隆抗体。  相似文献   
992.
尿素氮-葡萄糖双功能分析仪的研究   总被引:2,自引:0,他引:2  
由固定化脲酶、谷氨酸脱氢酶、谷氨酸氧化酶、葡萄糖氧化酶的复合酶膜组成的双电极系统,可以同时测定尿素氮和葡萄糖的含量,每次进样量为25μl,20s即可测定出尿素氮和葡萄糖的含量。在0~60mg/dl尿素氮、0~500mg/dl葡萄糖范围内具有良好的线性关系。连续测定20次的变异系数分别为1.02%和1.05%。酶膜使用寿命为两星期以上。此仪器可广泛应用于临床检验和体育训练中。  相似文献   
993.
2012年8月在广东省南岭自然保护区采集到6只森林型蝙蝠(3♀,3♂),其鼻部呈管状,毛被厚密而柔软,后腿、翼膜和尾膜被覆有棕色绒毛。体型较大,雌雄之间有明显差异,前臂长♀48.94~52.67mm,♂44.00~46.92 mm;核型为2n=44,FN=52;超声波为调频型,主频率为78.3 kHz。经鉴定为蝙蝠科管鼻蝠亚科的毛翼管鼻蝠(Harpiocephalus harpia)。这一发现使该物种在中国大陆地区目前的分布区与栖息地得以进一步核实和确认,弥补了该珍稀蝙蝠物种的分布、行为和生态学资料。  相似文献   
994.
995.
A rice spotted-leaf mutant was isolated from an ethane methyl sulfonate (EMS) -induced IR64 mutant bank. The mutant, designated as spl30 (spotted-leaf30), displayed normal green leaf color under shade but exhibited red-brown lesions under natural summer field conditions. Initiation of the lesions was induced by light and the symptom was enhanced at 33 (°) C relative to 26 (°) C. Histochemical staining did not show cell death around the red-brown lesions. Chlorophyll contents in the mutant were significantly lower than those of the wild type while the ratio of chlorophyll a/b remained the same, indicating that spl30 was impaired in biosynthesis or degradation of chlorophyll. Disease reaction patterns of the mutant to Xanthomonas oryzae pv. oryzae were largely unchanged to most races tested except for a few strains. Genetic analysis showed that the mutation was controlled by a single recessive gene, tentatively named spl30(t), which co-segregated with RM15380 on chromosome 3, and was delimited to a 94 kb region between RM15380 and RM15383. Spl30(t) is likely a novel rice spotted-leaf gene since no other similar genes have been identified near the chromosomal region. The genetic data and recombination populations provided in this study will enable further fine-mapping and cloning of the gene.  相似文献   
996.
目的观察缺血缺氧损伤对星形胶质细胞细胞活化和细胞周期的影响。方法用流式细胞仪及BrdU掺入法检测缺血缺氧后不同时间点星形胶质细胞细胞周期变化和细胞的增殖活力;用荧光免疫细胞化学技术测定胶质细胞纤维酸性蛋白(GFAP)及细胞周期蛋白cyclinD1的表达水平。结果体外缺血缺氧损伤后星形胶质细胞S期较正常组明显增高,6h达高峰,BrdU掺入法显示损伤后6h星形胶质细胞的增殖活力最高,而随后S期细胞数目及细胞增殖活力都呈下降趋势。在缺血缺氧早期,GFAP阳性染色增强,6h最高;缺血缺氧12h后GFAP阳性染色变弱,而cyclinD1的表达在损伤后逐渐增加,在24h时达高峰。结论缺血缺氧损伤激活星形胶质细胞,使其进入新的细胞周期,出现细胞的增殖反应;cyclinD1参与了损伤后星形胶质细胞的修复和增殖;细胞周期事件与星形胶质细胞的增殖活化密切相关。  相似文献   
997.
目的检测缺氧诱导因子-1α(hypoxia-inducible factor-1α,HIF-1α)和葡萄糖转运蛋白-1(glucose transporter-1,GLUT-1)在不同月龄大鼠椎间盘纤维环组织中的表达及其相关性,探讨HIF-1α及GLUT-1在椎间盘退变过程中的作用。方法取Wistar大鼠50只,分别以1,3,6,12,18个月龄分为5组。采用免疫组化法及Western blot法检测各组椎间盘中HIF-1α和GLUT-1表达情况。结果随着大鼠月龄的增长,其椎间盘纤维环组织中HIF-1α和GLUT-1的表达也发生变化,由低月龄组(1-3月龄)至成年组(6-12月龄)HIF-1α和GLUT-1表达逐渐减少,而老年组(18月龄)二者表达显著增加。且这种变化有显著统计学意义(P0.01)。纤维环中HIF-1α和GLUT-1的蛋白表达呈正相关。结论HIF-1α、GLUT-1表达水平的变化与椎间盘退变的发生关系密切相关,HIF-1α可以通过上调GLUT-1等相关因子并延缓椎间盘退变,可能作为椎间盘退变治疗研究的切入点。  相似文献   
998.
半散放东北虎行为活动时间的分配   总被引:7,自引:0,他引:7  
1998年5年-2001年4月在黑龙江东北虎林园,采用焦点动物取样法对10只半散放东北虎(5雌5雄)全年的昼间行为活动时间分配进行了研究。结果表明:(1)半散放东北虎的运动(37.53%)和休息(32.45%)行为较多,站立(6.24%),摄食(10.13%),社会(8.36%)和其他(5.29%,包括饮水,排遗,修饰等)行为较少;(2)不同季节的活动规律相似,运动,摄食,站立和社会行为在上午和下午各有1个高峰期,休息在中午有1个高峰期,运动和行为在存,冬季明显比春,秋季增多。将上述结果与笼养和野生东北虎的进行了比较,并提出了在今后的野化训练中应采取的措施。  相似文献   
999.
The ability to examine real-time reaction kinetics for multimeric enzymes in their native state may offer unique insights into understanding the catalytic mechanism and its interplay with three-dimensional structure. In this study, we have used a time-resolved electrospray mass spectrometry approach to probe the kinetic mechanism of 4-hydroxybenzoyl-coenzyme A (4-HBA-CoA) thioesterase from Arthrobacter sp. strain SU in the millisecond time domain. Intact tetrameric complexes of 4-HBA-CoA thioesterase with up to four natural substrate (4-HBA-CoA) molecules bound were detected at times as early as 6 ms using an online rapid-mixing device directly coupled to an electrospray ionization time-of-flight mass spectrometer. Species corresponding to the formation of a folded tetramer of the thioesterase at charge states 16+, 17+, 18+, and 19+ around m/z 3800 were observed and assigned as individual tetramers of thioesterase and noncovalent complexes of the tetramers with up to four substrate and/or product molecules. Real-time evaluation of the reaction kinetics was accomplished by monitoring change in peak intensity corresponding to the substrate and product complexes of the tetrameric protein. The mass spectral data suggest that product 4-HBA is released from the active site of the enzyme prior to the release of product CoA following catalytic turnover. This study demonstrates the utility of this technique to provide additional molecular details for an understanding of the individual enzyme states during the thioesterase catalysis and ability to observe real-time interactions between enzyme and substrates and/or products in the millisecond time range.  相似文献   
1000.
The genic multiple-allele inherited male-sterile gene Ms in Chinese cabbage (Brassica rapa L.) was identified as a spontaneous mutation. Applying this gene to hybrid seed production, several B. rapa cultivars have been successfully bred in China. A BC1 population (244 plants) was constructed for mapping the Ms gene. Screening 268 simple sequence repeat (SSR) markers which cover the entire genome of Chinese cabbage was performed with bulked segregant analysis (BSA). On the basis of linkage analysis, the Ms gene was located on linkage group R07. In addition, through the amplified fragment length polymorphism (AFLP) and the sequence-characterized amplified region (SCAR) techniques combining BSA, two SCAR markers which were converted from corresponding AFLP markers flanked the Ms gene. Finally, a genetic map of the Ms gene was constructed covering a total interval of 9.0 cM. Two SCAR markers, syau_scr01 and syau_scr04, flanked the Ms gene at distances of 0.8 and 2.5 cM, respectively. All the SSR markers (cnu_m273, cnu_m030, cnu_m295, and syau_m13) were mapped on the same side of the gene as syau_scr04, the nearest one of which, syau_m13, was mapped at a distance of 3.3 cM. These SSR and SCAR markers may be useful in marker-assisted selection and map-based cloning. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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