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981.
不同的微生物都可以引起腹腔感染,文中尝试利用尿液来区分不同的微生物感染.通过在大鼠腹腔内分别注射大肠杆菌、金黄色葡萄球菌和白色念球菌建立3种模型,收集感染后0、12、36、72h的尿液,并使用液相色谱串联质谱技术(LC-MS/MS)对尿蛋白进行分析.与感染前相比,在大肠杆菌腹腔注射模型中共鉴定到69个差异蛋白,在金黄色...  相似文献   
982.
983.
林蛙受精卵表面的大豆凝集素结合位点没有侧向运动,联在结合位点上的标记物在卵表面位置的改变应该可以反映卵表面运动。本文利用近景摄影测量术和侧向摄影法观测卵表面标记点位置的变化,得到下面的结果:1.卵裂前30—40min,整个卵表面都向预定分裂沟中心移动,表示卵表面在收缩。卵裂前15min左右,沟中心附近的卵表面开始松弛,随之是离沟较远处的卵表面松弛,显示卵表面有一个从预定分裂沟中心向四周传播的收缩波(图2—5)。如果以相邻标记点之间的距离变化作图(图6),则出现两个波,一个是松弛波,一个是收缩波。本文对卵表面究竟出现一个波还是两个波的问题进行了讨论。2.分裂沟中心附近收缩时,高程逐渐下降,基部两侧逐渐加宽(图7和图8);卵松弛时,高程增加,基部收缩。所以卵高程的变化也是从预定分裂沟中心波浪形地向四周传播的。3.卵裂沟出现前3—5 min,预定分裂沟两端开始向沟中心收缩,这是卵裂起动收缩。以后收缩范围逐渐扩大,强度亦增加,但预定分裂沟两侧的卵表面没有向预定分裂沟两端移动。这一结果支持了赤道区收缩的假说。  相似文献   
984.
Gao  Feng  Zhao  Shanshan  Men  Shuzhen  Kang  Zhensheng  Hong  Jian  Wei  Chunhong  Hong  Wei  Li  Yi 《中国科学:生命科学英文版》2020,63(11):1703-1713

RNA silencing is a potent antiviral mechanism in plants and animals. As a counter-defense, many viruses studied to date encode one or more viral suppressors of RNA silencing (VSR). In the latter case, how different VSRs encoded by a virus function in silencing remains to be fully understood. We previously showed that the nonstructural protein Pns10 of a Phytoreovirus, Rice dwarf virus (RDV), functions as a VSR. Here we present evidence that another nonstructural protein, Pns11, also functions as a VSR. While Pns10 was localized in the cytoplasm, Pns11 was localized both in the nucleus and chloroplasts. Pns11 has two bipartite nuclear localization signals (NLSs), which were required for nuclear as well as chloroplastic localization. The NLSs were also required for the silencing activities of Pns11. This is the first report that multiple VSRs encoded by a virus are localized in different subcellular compartments, and that a viral protein can be targeted to both the nucleus and chloroplast. These findings may have broad significance in studying the subcellular targeting of VSRs and other viral proteins in viral-host interactions.

  相似文献   
985.
Wu  Hao  Cui  Yuanting  He  Chengkang  Gao  Peng  Li  Qiang  Zhang  Hexuan  Jiang  Yanli  Hu  Yingru  Wei  Xiao  Lu  Zongshi  Ma  Tianyi  Liu  Daoyan  Zhu  Zhiming 《中国科学:生命科学英文版》2020,63(11):1665-1677
Science China Life Sciences - High salt intake is a known risk factor of cardiovascular diseases. Our recent study demonstrated that long-term high salt intake impairs transient receptor potential...  相似文献   
986.
试论“三北”生态经济型防护林体系   总被引:7,自引:0,他引:7  
本文介绍了“三北”防护林体系工程的概要、建设指导思想和技术路线,从理论上较深入地探讨了林业观念更新的意义及其基础。从而,提出“生态经济型防护林体系”的学术概念,以及它同建立区域性人工生态系统的相互关系,并结合“三北”黄土高原昕水河流域生态经济型防护林体系示范区的特点进行分析,探讨丘陵山地条件下,生态经济型防护林体系的技术内涵、组成及其生态经济特点。最后,作者提出了由“三北”防护林工程的实践对我国如何建设好其它防护林工程的几点启示。  相似文献   
987.
988.
Tilletia laevis Kühn (syn. Tilletia foetida (Wallr.) Liro.) causes wheat common bunt, which is one of the most devastating plant diseases in the world. Common bunt can result in a reduction of 80% or even a total loss of wheat production. In this study, the characteristics of T. laevis infection in compatible wheat plants were defined based on the combination of scanning electron microscopy, transmission electron microscopy and laser scanning confocal microscopy. We found T. laevis could lead to the abnormal growth of wheat tissues and cells, such as leakage of chloroplasts, deformities, disordered arrangements of mesophyll cells and also thickening of the cell wall of mesophyll cells in leaf tissue. What’s more, T. laevis teliospores were found in the roots, stems, flag leaves, and glumes of infected wheat plants instead of just in the ovaries, as previously reported. The abnormal characteristics caused by T. laevis may be used for early detection of this pathogen instead of molecular markers in addition to providing theoretical insights into T. laevis and wheat interactions for breeding of common bunt resistance.  相似文献   
989.
BackgroundVisceral leishmaniasis (VL) has been declared as one of the six major tropical diseases by the World Health Organization. This disease has been successfully controlled in China, except for some areas in the western region, such as the Xinjiang Autonomous Region, where both anthroponotic VL (AVL) and desert type zoonotic VL (DT-ZVL) remain endemic with sporadic epidemics.Methodology/Principal findingsHere, an eleven-year survey (2004–2014) of Leishmania species, encompassing both VL types isolated from patients, sand-fly vectors and Tarim hares (Lepus yarkandensis) from the Xinjiang Autonomous Region was conducted, with a special emphasis on the hares as a potential reservoir animal for DT-ZVL. Key diagnostic genes, ITS1, hsp70 and nagt (encoding N-acetylglucosamine-1-phosphate transferase) were used for phylogenetic analyses, placing all Xinjiang isolates into one clade of the L. donovani complex. Unexpectedly, AVL isolates were found to be closely related to L. infantum, while DT-ZVL isolates were closer to L. donovani. Unrooted parsimony networks of haplotypes for these isolates also revealed their relationship.Conclusions/SignificanceThe above analyses of the DT-ZVL isolates suggested their geographic isolation and independent evolution. The sequence identity of isolates from patients, vectors and the Tarim hares in a single DT-ZVL site provides strong evidence in support of this species as an animal reservoir.  相似文献   
990.
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