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111.
动物实验人员的素质是决定医院动物实验工作质量的重要因素.但通常被忽视。随着动物实验标准化进程的不断推进,提高动物实验工作人员的素质、增强专业技能就显得尤为重要。本文结合我院实践主要阐述综合性医院动物实验工作的特点、对动物实验工作人员基本素质的要求以及培养和提高的途径。  相似文献   
112.
北京市11种园林植物滞留大气颗粒物能力研究   总被引:36,自引:2,他引:36  
测定了北京市11种园林植物叶面颗粒物附着密度,利用环境扫描电镜观察比较了各测试树种叶表面微形态,测量统计了滞留颗粒物的粒径分布.结果表明,植物主要通过叶片上表面滞留大气颗粒物,上表面滞留的大气颗粒物数量约为下表面的5倍;叶片上表面滞留大气颗粒物能力由高到低的微形态结构依次是沟槽>叶脉+小室 >小室>条状突起,并且结构越密集、深浅差别越大,越有利于滞留大气颗粒物;测试树种叶片上、下表面PM2.5和PM10平均百分含量分别为66.7%和98.3%与 43.4%和92.9%.  相似文献   
113.
Mucins are synthesized and secreted by many epithelia. They are complex glycoproteins that offer cytoprotection. In their functional configuration, mucins form oligomers by a biosynthetic process that is poorly understood. A family of four human gastrointestinal mucin genes (MUC2, MUC5AC, MUC5B, and MUC6) is clustered to chromosome 11p15.5. To study oligomerization of these related mucins, we performed metabolic labeling experiments with [35S]amino acids in LS174T cells, and isolated mucin precursors by specific immunoprecipitations that were analyzed on SDS-PAGE. Each of the precursors of MUC2, MUC5AC, MUC5B, and MUC6 formed a single species of disulfide-linked homo-oligomer within 1 h after pulse labeling. Based on apparent molecular masses, these oligomeric precursors were most likely dimers. Inhibition of vesicular RER-to-Golgi transport, with brefeldin A and CCCP, did not affect the dimerization of MUC2 precursors, localizing dimerization to the RER. O-Glycosylation of MUC2 followed dimerization. Inhibition of N- glycosylation by tunicamycin retarded, but did not inhibit, dimerization, indicating that N-glycans play a role in efficient dimerization of MUC2 precursors. Based on sequence homology, the ability of MUC2, MUC5AC, MUC5B and MUC6 to dimerize most likely resides in their C-terminal domains. Thus, the RER-localized dimerization of secretory mucins likely proceeds by similar mechanisms, which is an essential step in the formation of the human gastrointestinal mucus- gels.   相似文献   
114.
Plants traditionally used to dye carpets and woven matting in the eastern Mediterranean region were investigated. The survey was carried out in Kadirli, Feke, Aladağ, the surrounding villages of Adana, and in Osmaniye (Turkey). According to the survey results, 37 species of plants belonging to 29 families were used in natural dye production. The total dye contents of collected plants ranged from 1.5% to 10.0%. Mordants and dyes obtained from some of these plants were used to treat wool yarn and the yarn's dyed properties were tested. Some of the plants were also examined in terms of cultivation and fifteen were transferred to a Dye Plants Collection Garden. They were Alnus glutinosa (L.) Gaertn. ssp. antitaurica Yalt., Arctium minus ssp. pubens (Bab.) Arènes, Chrysanthemum segetum L., Cistus creticus L., Cotinus coggygria Scop., Datisca cannabina L., Galium verum ssp. glabrescens Ehrend., Isatis tinctoria ssp. tomentella (Boiss. & Balansa) P.H.Davis, Melissa officinalis ssp. inodora Bornm., Mentha longifolia (L.) Huds. ssp. longifolia , Reseda lutea var. lutea L., Rhamnus oleoides ssp. graecus (Boiss. & Reut.) Holmboe, Rhus coriaria L., Rubia tinctorum L., and Rumex patientia L.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 71–77.  相似文献   
115.
大豆疫霉菌的EMS化学诱变   总被引:1,自引:0,他引:1  
以甲基磺酸乙酯(ethylmethane sulfonate,EMS)为诱变剂,通过其对大豆疫霉菌Phytophthora sojae休止孢萌发的影响,确定化学诱变条件。通过收集单卵孢子,建立了包含640个单卵孢子系的突变体库,其中约有50%的诱变菌系在培养性状和菌落形态方面发生了明显变化,菌落形态多样,表现出较紧密或松散,近圆形或不规则;气生菌丝减少,生长速度较慢或快;在卵孢子产量方面,8.13%的菌系有增加,20.41%的菌系减少,27.82%的菌系极少或者没有卵孢子产生,43.64%的菌系卵孢子产量类似野生型。以质膜氢离子泵蛋白基因PsPMA1(plasma membrane H+-ATPase1)为对象,通过TILLING技术,从320个大豆疫霉菌突变体中获得9个突变体,进一步确认了EMS对大豆疫霉菌的诱变效果,并且估算EMS对大豆疫霉菌的诱变频率至多每115kb发生一个核苷酸变异。新构建的突变体库为开展大豆疫霉病菌的功能基因组研究奠定了遗传材料基础。  相似文献   
116.
1. It is widely acknowledged that sudden, large‐scale flood pulses are drivers of benthic and planktonic biodiversity change in floodplains. The impact of such pulses on pleuston (biotic communities associated with root systems of floating plants) remains to be demonstrated. Here, we investigate the effects of local and regional drivers on seasonal changes in abundance and diversity of ostracod communities in pleuston. 2. Temporal and spatial distribution patterns of species richness, abundance, diversity and evenness of ostracods associated with the floating water hyacinth, Eichhornia crassipes, in a lentic environment from the upper Paraná River floodplain, were investigated in relation to local, as well as regional, environmental factors. Ostracods were sampled monthly over an annual cycle (March 2004–February 2005). Twenty‐seven species were found, representing the families Cyprididae, Candonidae, Limnocytheridae and Darwinulidae. Both diversity and abundance of ostracod communities showed seasonal changes, although species turn‐over during the year was limited. 3. We tested two hypotheses concerning the causality of these fluctuations: seasonal recruitment and influx of allochthonous ostracods during the flood pulse. Our results indicate that seasonal recruitment is more likely to be the driver of fluctuations in relation to the flood pulse. We postulate that pleuston communities are buffered against possible detrimental effects of flood pulses.  相似文献   
117.
Agrobacterium‐mediated gene transformation was used to introduce plastidic protoporphyrinogen IX oxidase (Protox) genes from Arabidopsis, with and without the transit sequence, into the rice genome. They were placed under the control of the constitutive and ubiquitous maize ubiquitin promoter, and their abilities to confer resistance to the diphenyl ether‐type herbicide, oxyfluorfen were compared. The integration and expression of the transgene in the T1 generation was examined by Southern, northern and western blot analyses. Surprisingly, as judged by an in vivo seed germination assay and an in vitro cellular leakage assay, both lines were similarly resistant to oxyfluorfen. The tolerance to cellular damage (lipid peroxidation and electrolyte leakage) was higher in transgenic plants than in wild‐type plants. In transgenic plants, the degree of herbicide resistance varied directly with the absolute amount of Protox protein expression. Both the intact protein and the protein with the transit sequence deleted were accumulated in plastids.  相似文献   
118.
目的:用缺口修复等技术构建Myostatin(肌肉生长抑制素,MSTN)基因打靶载体,并对大白猪胎儿成纤维体细胞进行转染,获得基因敲除细胞。方法与结果:首先构建用于MSTN基因同源长臂(LA)的抓捕载体,然后在大肠杆菌内利用Red同源重组系统介导的缺口修复,从含大白猪MSTN基因座的细菌人工染色体上亚克隆9.9 kb的LA到抓捕载体上,经过部分序列测定,同源性为100%;通过PCR获得1.4 kb的同源短臂(SA);将LA和SA连入载体pLOXP,构建含有neo和tk正负筛选标记基因的MSTN基因打靶载体pLOXP-MSTN-KO;将线性化的pLOXP-MSTN-KO通过电转染整合到大白猪胎儿成纤维细胞基因组中,利用G418和丙氧鸟苷进行药物筛选,获得抗性细胞克隆890个,通过PCR和DNA测序鉴定获得基因敲除的细胞克隆4个。结论:构建了有效的MSTN基因打靶载体,通过转染获得基因敲除细胞,为利用体细胞核移植制备MSTN基因敲除猪奠定了基础。  相似文献   
119.
松香改性的研究进展   总被引:29,自引:0,他引:29  
本文综述了近年来松香改性的研究进展情况,对其进行了分类阐述,即基于羧基的改性、基于双键的改性、基于羧基和双键的改性以及其它方面的改性,并展望了此领域的发展趋势和前景。  相似文献   
120.
目的:回顾分析各种非小细胞肺癌(non-small cell lung cancer,NSCLC)的治疗方案及影响其治疗预后的因素,为合理制定个体化的综合治疗方案提供参考。方法:回顾分析近年来NSCLC治疗的研究报道,分析如病理分期、实验室检查结果(VEGF、WBC、Hg等)影响治疗预后的因素,建议相应的治疗对策。结果:1.Ⅰ期、Ⅱ期及部分Ⅲa期NSCLC的患者治疗措施首先以手术治疗为主,同步放化疗比单纯放、化疗及序贯放化疗更能有效改善晚期NSCLC的预后;2.个体相关因素、肿瘤相关因素和治疗相关因素影响NSCLC治疗预后。结论:同步放化疗在晚期NSCLC的治疗中有重要作用,肿瘤的病理分期、血浆VEGF浓度是影响NSCLC预后的独立因素。  相似文献   
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