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991.
Sun Weifeng Wu Yuanming Ding Wenwu Wang Li Wu Lunjie Lin Lu Che Zhenming Zhu Longbao Liu Yi Chen Xiaohua 《Bioprocess and biosystems engineering》2020,43(4):701-710
Bioprocess and Biosystems Engineering - Currently, some cases about the expression of flavor peptides with microorganisms were reported owing to the obvious advantages of biological expression over... 相似文献
992.
993.
Luo Dan Xia Zhi Li Heng Tu Danna Wang Ting Zhang Wei Peng Lu Yi Wenfu Zhang Sai Shu Junhua Xu Hui Li Yong Shi Buyun Huang Chengjiao Tang Wen Xiao Shuna Shu Xiaolan Liu Yan Zhang Yuan Guo Shan Yu Zhi Wang Baoxiang Gao Yuan Hu Qinxue Wang Hanzhong Song Xiaohui Mei Hong Zhou Xiaoqin Zheng Zhenhua 《中国病毒学》2020,35(6):861-867
In December 2019, SARS-CoV-2 was first detected in the samples obtained from three adult patients who suffered from an unknown viral pneumonia in Wuhan (Li et al. 2020). This unknown viral pneumonia is further named as coronavirus disease 2019 (COVID-19) by the World Health Organization. To date, the number of new COVID-19 cases has continued to skyrocket and the impact of SARS-CoV-2 on humans is far greater than any pathogen of this century in both breadth and depth. Previous studies have shown that adults with COVID-19 have symptoms of fever, dry cough, dyspnea, fatigue and lymphocytopenia. Moreover, COVID-19 is more likely to cause death in the elderly, especially those with chronic comorbidities (Huang et al. 2020). In Wuhan, more than 50, 000 COVID-19 cases have been confirmed, including over 780 pediatric patients, and only one child death case (Lu et al. 2020). Although the number of children cases was far fewer than that of adults, COVID-19 might endanger children's health and the information on children remains limited, especially in serological study. In the retrospective study, the investigators analyzed the epidemiological, clinical and serological characteristics of children with COVID-19 in Wuhan in the early stages of the outbreak, which might provide theoretical and practical help in controlling COVID-19 and similar emerging infectious diseases in the future. 相似文献
994.
Brain-to-brain interfaces(BtBIs) hold exciting potentials for direct communication between individual brains. However,technical challenges often limit their performance in rapid information transfer. Here, we demonstrate an optical brain-to-brain interface that transmits information regarding locomotor speed from one mouse to another and allows precise, real-time control of locomotion across animals with high information transfer rate. We found that the activity of the genetically identified neuromedin B(NMB) neurons within the nucleus incertus(NI) precisely predicts and critically controls locomotor speed. By optically recording Ca~(2+) signals from the NI of a "Master" mouse and converting them to patterned optogenetic stimulations of the NI of an "Avatar" mouse, the Bt BI directed the Avatar mice to closely mimic the locomotion of their Masters with information transfer rate about two orders of magnitude higher than previous Bt BIs. These results thus provide proof-of-concept that optical Bt BIs can rapidly transmit neural information and control dynamic behaviors across individuals. 相似文献
995.
本研究通过体外生化实验研究细胞色素P450 3A7对维生素D3的羟化作用。根据GenBank报道的序列设计特异引物,扩增cyp3a7的编码区,将cyp3a7的编码区插入到pcDNATM3.1/myc-His(-) A的XhoⅠ/Bam HⅠ,通过测序检测序列的正确性。pcDNA-CYP3A7及pcDNA分别瞬时转染293T细胞,48 h后收集细胞,提取S9组分,用Bradford法测定蛋白质浓度。S9组分经12%SDS-PAGE凝胶电泳和Western blotting检测,用myc抗体作为一抗检测CYP3A7在293T细胞的表达水平。0.6 mg S9组分与1μmol/L维生素D3于37℃孵育30 min,用4倍体积的氯仿甲醇(体积比为3∶1)抽提,有机相在氮气流下吹干,残基用于HPLC分析。结果显示,重组表达CYP3A7的293T细胞的S9组分通过Western blotting检测到了特异的约60 kD的条带,对照样品未检测到特异条带的蛋白质。重组表达CYP3A7的293T细胞S9组分的孵育样品通过HPLC检测到了25-羟基维生素D3,对照样品未检测到25-羟基维生素D3。结果表明重组表达的CYP3A7羟化维生素D3生成25-羟基维生素D3。本研究为进一步探究还有哪些P450参与维生素D3在鸡体内的代谢,为阐明其代谢途径提供理论依据。 相似文献
996.
Jun‐Xia Su Cong‐Cong Dong Yan‐Ting Niu Li‐Min Lu Chao Xu Bing Liu Shi‐Liang Zhou An‐Ming Lu Yu‐Ping Zhu Jun Wen Zhi‐Duan Chen 《植物分类学报:英文版》2020,58(5):710-724
Species concept and delimitation are fundamental to taxonomic and evolutionary studies. Both inadequate informative sites in the molecular data and limited taxon sampling have often led to poor phylogenetic resolution and incorrect species delineation. Recently, the whole chloroplast genome sequences from extensive herbarium specimen samples have been shown to be effective to amend the problem. Stachyuraceae are a small family consisting of only one genus Stachyurus of six to 16 species. However, species delimitation in Stachyurus has been highly controversial because of few and generally unstable morphological characters used for classification. In this study, we sampled 69 individuals of seven species (each with at least three individuals) covering the entire taxonomic diversity, geographic range, and morphological variation of Stachyurus from herbarium specimens for genome‐wide plastid gene sequencing to address species delineation in the genus. We obtained high‐quality DNAs from specimens using a recently developed DNA reconstruction technique. We first assembled four whole chloroplast genome sequences. Based on the chloroplast genome and one nuclear ribosomal DNA sequence of Stachyurus, we designed primers for multiplex polymerase chain reaction and high throughput sequencing of 44 plastid loci for species of Stachyurus. Data of these chloroplast DNA and nuclear ribosomal DNA internal transcribed spacer sequences were used for phylogenetic analyses. The phylogenetic results showed that the Japanese species Stachyurus praecox Siebold & Zucc. was sister to the rest in mainland China, which indicated a typical Sino‐Japanese distribution pattern. Based on diagnostic morphological characters, distinct distributional range, and monophyly of each clade, we redefined seven species for Stachyurus following an integrative species concept, and revised the taxonomy of the family based on previous reports and specimens, in particular the type specimens. Furthermore, our divergence time estimation results suggested that Stachyuraceae split from its sister group Crossosomataceae from the New World at ca. 54.29 Mya, but extant species of Stachyuraceae started their diversification only recently at ca. 6.85 Mya. Diversification time of Stachyurus in mainland China was estimated to be ca. 4.45 Mya. This research has provided an example of using the herbarium specimen‐based phylogenomic approach in resolving species boundaries in a taxonomically difficult genus. 相似文献
997.
Li Tao Tang Xiaolu Wu Changcheng Yao Xinmin Wang Yirong Lu Xuemei Lu Jian 《中国科学:生命科学英文版》2020,63(10):1608-1611
正Dear Editor,The coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 coronavirus has become a global pandemic.The SARS-CoV-2 genome has a similarity of 96.2%to that of RaTG13, a bat SARS-CoV-2-related coronavirus detected in Rhinolophus affinis (Paraskevis et al., 2020; Zhou et al.,2020). The SARS-CoV-2 genome also has 85.5%-92.4% 相似文献
998.
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
999.
Lu Ligong Zhang Hui Zhan Meixiao Jiang Jun Yin Hua Dauphars Danielle J. Li Shi-You Li Yong He You-Wen 《中国科学:生命科学英文版》2020,63(12):1833-1849
Science China Life Sciences - The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected millions of people and caused tremendous morbidity and mortality worldwide.... 相似文献
1000.
Ba Limin Wang Zhenbao Liu William J Wu Dongxun Xiang Wangzhen Qi Peng Dong Chunna Hu Yanxin Lu Ping Xiao Jin Yu Changyuan 《中国科学:生命科学英文版》2020,63(10):1604-1607
正Dear Editor,Swine major histocompatibility complex (MHC) is a highly polymorphic gene in pigs and is also called swine leukocyte antigen (SLA)(Fan et al., 2018). SLA is divided into three major categories, SLA Ⅰ (SLA-1,-2,-3), SLA Ⅱ, and SLA Ⅲ(Smith et al., 2005). SLA Ⅰ plays an important role in cellular immunity which can eliminate viruses and other foreign 相似文献