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991.
Virologica Sinica - 3h-31 of Heliothis virescens ascovirus 3h (HvAV-3h) is a highly conserved gene of ascoviruses. As an early gene of HvAV-3h, 3h-31 codes for a non-structural protein (3H-31) of... 相似文献
992.
Luo Shengxue Zhang Panli Zou Peng Wang Cong Liu Bochao Wu Cuiling Li Tingting Zhang Ling Zhang Yuming Li Chengyao 《中国病毒学》2021,36(5):1113-1123
Virologica Sinica - SARS-CoV-2 has caused more than 3.8 million deaths worldwide, and several types of COVID-19 vaccines are urgently approved for use, including adenovirus vectored vaccines.... 相似文献
993.
Yi-Fei Lu Xiao-Feng Jin Hiroshi Ikeda Okihito Yano Carmen Benítez-Benítez Wei-Jie Chen Yong-Di Liu Pedro Jiménez-Mejías Ming-Jian Yu 《植物分类学报:英文版》2021,59(4):668-686
Carex sect. Confertiflorae s.l. is a medium-sized species group (ca. 40 species) with its center of diversity in E Asia (China and Japan). According to morphological traits, the section has been proposed to split into two sections (sects. Confertiflorae sensu Ohwi and Molliculae Ohwi) up to five different ones (sects. Confertiflorae s.s., Molliculae, Dispalatae Ohwi, Ischnostachyae Ohwi, and Alliiformes Akiyama). Recent phylogenetic reconstructions showed Confertiflorae s.l. not to be monophyletic, as species traditionally considered part of it were found to belong to other clades, whereas species traditionally ascribed to other sections were nested within it. In this study, we investigated the phylogenetic structure, morphological affinities, and biogeographic history of sect. Confertiflorae s.l. We employed a taxon-based approach to explore the morphological affinities of the species considered in sect. Confertiflorae and compared the micromorphology of the nutlets of almost all the taxa using SEM. We included 40 samples representing 31 species/subspecies of sect. Confertiflorae s.l. and used two nuclear (ETS and ITS) and three plastid (trnL-F, matK, and rpl32-trnL UAG) molecular markers to reconstruct the phylogeny of the group. The phylogenetic analyses confirmed the polyphyly of sect. Confertiflorae s.l., whose representatives were found within five distinct clades. From these, two clades, sect. Confertiflorae and sect. Molliculae, were found to be closely related and contained the majority of the species. The composition of the two clades agreed with the morphological structure of the group, and we confirmed an exclusive combination of features (namely color of basal sheaths, presence of bract sheath, peduncle of lowest spike, inflorescence sex distribution, shape of pistillate glume apex, and color and veins of utricle, among others) characterizing each of the two clades. The origin of the two clades was found to be in the early Pliocene; however, the majority of the diversification events within each clade took place during the Pleistocene. This illustrates that although Asia has been regarded as having little potential ecological space for Carex to diversify due to its climate stability, groups of sedges sub-endemic from that area may have a fairly recent origin related to glaciations. We proposed the rearrangement of sect. Confertiflorae as previously conceived as three independent sections: the monotypic Alliiformes, sect. Molliculae, and sect. Paludosae. 相似文献
994.
高血压(hypertension,high blood pressure)是动脉血压持续偏高的慢性疾病,是人类社会最为常见的慢性医学问题.80%以上的高血压患者了解他们自身的血压状况,其中70%以上的患者服用治疗高血压药物.然而,这些认识到自身高血压状况的人中,只有48%的患者的高血压得到了充分的控制.本文系统地阐述了高血压的类型、诊断标准及治疗或控制策略,以期提高公众对高血压的认知,有利于患者对高血压的控制和管理. 相似文献
995.
The diversity of axon guidance (AG) receptors reflects gains in complexity of the animal nervous system during evolution. Members of the Roundabout (Robo) family of receptors interact with Slit proteins and play important roles in many developmental processes, including AG and neural crest cell migration. There are four members of the Robo gene family. However, the evolutionary history of Robo family genes remain obscure. We analyzed the distribution of Robo family members in metazoan species ranging in complexity from hydras to humans. We undertook a phylogenetic analysis in metazoans, synteny analysis, and ancestral chromosome mapping in vertebrates, and detected selection pressure and functional divergence among four mammalian Robo paralogs. Based on our analysis, we proposed that the ancestral Robo gene could have undergone a tandem duplication in the vertebrate ancestor; then one round of whole genome duplication events occurred before the divergence of ancestral lamprey and gnathostome, generating four paralogs in early vertebrates. Robo4 paralog underwent segmental loss in the following evolutionary process. Our results showed that Robo3 paralog is under more powerful purifying selection pressure compared with other three paralogs, which could correlate with its unique expression pattern and function. Furthermore, we found four sites under positive selection pressure on the Ig1‐2 domains of Robo4 that might interfere with its binding to Slits ligand. Diverge analysis at the amino acid level showed that Robo4 paralog have relatively greater functional diversifications than other Robo paralogs. This coincides with the fact that Robo4 predominantly functions in vascular endothelial cells but not the nervous system. 相似文献
996.
997.
Wan Qiangyou Kong Deping Liu Qian Guo Shumin Wang Chenchen Zhao Yan Ke Zun-Ji Yu Ying 《中国科学:生命科学英文版》2021,64(7):1068-1076
Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit prostaglandin (PG) formation by targeting cyclooxygenase (COX) 1 and 2.Long-term use of NSAIDs that selectively inhibit COX2 increases the risk for thrombotic events,cardiac failure,and hypertension.However,the underlying mechanisms remain unclear.In this study,COX1- and COX2-deficient rats were created via Cas9/RNA-mediated gene targeting.DNA genotyping and Western blot analysis confirmed successful generation of COX1~(-/-)and COX2~(-/-)rats.Adult COX1~(-/-)rats grew normally,while more than 70%of COX2~(-/-)rats after wean died within 2 months.Echocardiography showed markedly reduced left ventricular ejection fraction and fractional shortening in adult COX2~(-/-)rats compared to those in wildtype (WT) controls.Histological analysis revealed accumulation of inflammatory cells and severe interstitial and perivascular fibrosis in COX2~(-/-)cardiac tissues.Moreover,cardiac ATP and acetyl-Co A production was dramatically decreased in COX2~(-/-)rats.Consistently,the expression of genes related to mitochondrial oxidation,such as those that encode for subunits of pyruvate dehydrogenase complex and acyl Co A dehydrogenases,were downregulated,while glycolytic hexokinase 1 (HK1) was upregulated in COX2~(-/-)heart tissues.These observations indicate that COX2-deficient rats developed spontaneously heart failure,likely as a result of dysregulated cardiac energy metabolism. 相似文献
998.
Yang Teng Shi Yu Zhu Jun Zhao Chang Wang Jianmei Liu Zhiyong Fu Xiao Liu Xu Yan Jiangwei Yuan Meiqing Chu Haiyan 《中国科学:生命科学英文版》2021,64(9):1546-1559
Urban soils harbor billions of bacterial cells and millions of species. However, the distribution patterns and assembly processes of bacterial communities remain largely uncharacterized in urban soils. It is also unknown if we can use the bacteria to track soil sources to certain cities and districts. Here, Illumina MiSeq sequencing was used to survey soil bacterial communities from 529 random plots spanning 61 districts and 10 major cities in China. Over a 3,000 km range, community similarity declined with increasing geographic distance(Mantel r=0.62), and community composition was clustered by city(R~2=0.50). Within cities(100 km), the aforementioned biogeographic patterns were weakened. Process analysis showed that homogenizing dispersal and dispersal limitation dominated soil bacterial assembly at small and large spatial scales, respectively. Accordingly, the probabilities of accurately tracking random soil sources to certain cities and districts were 90.0% and 66.7%, respectively. When the tested samples originated from cities that were more than 1,265 km apart, the soil sources could be identified with nearly 100% accuracy. Overall, this study demonstrates the strong distance-decay relationship and the clear geographic zoning of urban soil bacterial communities among cities. The varied importance of different community assembly processes at multiple spatial scales strongly affects the accuracy of microbial source tracking. 相似文献
999.
Ran Chao Li Yu Ma Xufa Xie Yadong Xie Mingxu Zhang Yuting Zhou Wei Yang Yalin Zhang Zhen Zhou Li Wei Kaijian Zhou Zhigang 《中国科学:生命科学英文版》2021,64(9):1437-1448
Viral diseases cause serious economic loss in farmed animals industry. However, the efficacy of remedies for viral infection in farmed animals is limited, and treatment strategies are generally lacking for aquatic animals. Interactions of commensal microbiota and viral infection have been studied in recent years, demonstrating a third player in the interaction between hosts and viruses. Here, we discuss recent developments in the research of interactions between commensal bacteria and viral infection,including both promotion and inhibition effect of commensal bacteria on viral pathogenesis, as well as the impact of viral infection on commensal microbiota. The antiviral effect of commensal bacteria is mostly achieved through priming or regulation of the host immune responses, involving differential microbial components and host signaling pathways, and gives rise to various antiviral probiotics. Moreover, we summarize studies related to the interaction between commensal bacteria and viral infection in farmed animals, including pigs, chickens, fish and invertebrate species. Further studies in this area will deepen our understanding of antiviral immunity of farmed animals in the context of commensal microbiota, and promote the development of novel strategies for treatment of viral diseases in farmed animals. 相似文献
1000.
场效应晶体管生物传感器因其灵敏度高、分析速度快、无标记、体积小、操作简单等特点而受到了很多关注,广泛应用于DNA、蛋白质、细胞、离子等生物识别物的检测。近年来,更有纳米材料和微电子技术在传感器设计中提高传感器的传感性能,场效应晶体管生物传感器朝着高灵敏、微型化、快速化以及多功能化的方向以令人惊叹的速度发展。研究场效应晶体管生物传感器工作原理,阐述近年来场效应晶体管生物传感器在生物医学检测领域中最新的研究进展与应用,探讨场效应晶体管生物传感器克服各种缺陷的应对策略,为该传感器在未来生物医学检测中的开发提供参考。 相似文献