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121.
Two novel hydroquinone derivatives, named guttaquinol A and B (1, 2), together with fifteen known compounds (3–17), were isolated from the roots of Arnebia guttata Bge.. Spectroscopic methods, including NMR, HR-MS, ECD, and data from the literature were used to determine the chemical structures (including the absolute configurations) of the compounds. The chemotaxonomic significance of the isolated compounds was also discussed. 相似文献
122.
Kunitz型丝氨酸蛋白酶抑制剂是一类普遍存在的蛋白酶抑制剂,在体内各项生命活动中扮演着重要角色。这类抑制剂结构稳定且富有特色,通常具有一个或几个串联存在的Kunitz结构域,能够以类似底物的方式与丝氨酸蛋白酶结合,从而抑制酶的活性。在功能方面,Kunitz型丝氨酸蛋白酶抑制剂参与凝血和纤维蛋白溶解、肿瘤免疫、炎症调节以及抵抗细菌、真菌感染等过程。文中就Kunitz型丝氨酸蛋白酶抑制剂研究进展作一综述,为新型Kunitz型丝氨酸蛋白酶抑制剂的开发提供研究思路。 相似文献
123.
《L'Anthropologie》2021,125(4):102923
The study is focused on comparative analysis of the five dwellings of the Anosov-Mezin type from the East-Epigravettian site of Yudinovo (Bryansk region, Russia). The analysis is based on data on previously unknown structural elements and methods of installation of mammoth skulls in the basement of dwelling No 5, which were revealed during excavations in 2015–2018. Apart of this the non-utilitarian actions that accompanied the process of dwellings construction was considered. Based on the revealed differences in structural elements and features, it was suggested that the currently used concept Anosovka-Mezin type of dwellings includes two types of the circular structures made of skulls and large mammoth bones. 相似文献
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The DM9 domain is a protein unit of 60–75 amino acids that has been first detected in the fruit fly Drosophila as a repeated motif of unknown function. Recent research on proteins carrying DM9 domains in the mosquito Anopheles gambiae and the oyster Crassostrea gigas indicated an association with the uptake of microbial organisms. Likewise, in the trematode Fasciola gigantica DM9-1 showed intracellular relocalization following microbial, heat and drug stress. In the present research, we show that FgDM9-1 is a lectin with a novel mannose-binding site that has been recently described for the protein CGL1 of Crassostrea gigas. This property allowed FgDM9-1 to agglutinate gram-positive and -negative bacteria with appropriate cell surface glycosylation patterns. Furthermore, FgDM9-1 caused hemagglutination across all ABO blood group phenotypes. It is speculated that the parenchymal located FgDM9-1 has a role in cellular processes that involve the transport of mannose-carrying molecules in the parenchymal cells of the parasite. 相似文献
127.
Virologica Sinica - Ebola virus (EBOV) belongs to the Filoviridae family and causes severe illnesses such as hemorrhagic fever with a high mortality rate up to 90%. Now two antibody drugs termed... 相似文献
128.
Li Jiang-Fan He Lei Deng Yong-Qiang Qi Shu-Hui Chen Yue-Hong Zhang Xiao-Lu Hu Shi-Xiong Fan Rui-Wen Zhao Guang-Yu Qin Cheng-Feng 《中国病毒学》2021,36(6):1484-1491
Virologica Sinica - The sudden emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) has caused global panic in 2003, and the risk of SARS-CoV outbreak still exists. However, no... 相似文献
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Qudsia Yousafi Ayesha Sarfaraz Muhammad Saad Khan Shahzad Saleem Umbreen Shahzad Azhar Abbas Khan Mazhar Sadiq Allah Ditta Abid Muhammad Sohail Shahzad Najam ul Hassan 《Saudi Journal of Biological Sciences》2021,28(4):2197-2209
Lepidoptera is the second most diverse insect order outnumbered only by the Coeleptera. Acetylcholinesterase (AChE) is the major target site for insecticides. Extensive use of insecticides, to inhibit the function of this enzyme, have resulted in the development of insecticide resistance. Complete knowledge of the target proteins is very important to know the cause of resistance. Computational annotation of insect acetylcholinesterase can be helpful for the characterization of this important protein. Acetylcholinesterase of fourteen lepidopteran insect pest species was annotated by using different bioinformatics tools. AChE in all the species was hydrophilic and thermostable. All the species showed lower values for instability index except L. orbonalis, S. exigua and T. absoluta. Highest percentage of Arg, Asp, Asn, Gln and Cys were recorded in P. rapae. High percentage of Cys and Gln might be reason for insecticide resistance development in P. rapae. Phylogenetic analysis revealed the AChE in T. absoluta, L. orbonalis and S. exigua are closely related and emerged from same primary branch. Three functional motifs were predicted in eleven species while only two were found in L. orbonalis, S. exigua and T. absoluta. AChE in eleven species followed secretory pathway and have signal peptides. No signal peptides were predicted for S. exigua, L. orbonalis and T. absoluta and follow non secretory pathway. Arginine methylation and cysteine palmotylation was found in all species except S. exigua, L. orbonalis and T. absoluta. Glycosylphosphatidylinositol (GPI) anchor was predicted in only nine species. 相似文献