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81.
叶表面角质层在贝母属植物叶鉴定中的意义 总被引:2,自引:0,他引:2
叶表面角质层在贝母属植物叶鉴定中的意义李萍,濮祖茂,蒋鑫,刘惠娟,徐国钧(中国药科大学生药学教研室;分析中心电镜室南京210009)ThediagnosticvalueofthecuticleintheleavesfromgenusFritillar... 相似文献
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Yuxiang Yao Hongzhi Tang Huixue Ren Hao Yu Lijuan Wang Ping Xu 《Journal of bacteriology》2012,194(20):5714-5715
We announce a 4.63-Mb genome assembly of an isolated bacterium that is the first sequenced nicotine-degrading Arthrobacter strain. Nicotine catabolism genes of the nicotine-degrading plasmid pAO1 were predicted, but plasmid function genes were not found. These results will help to better illustrate the molecular mechanism of nicotine degradation by Arthrobacter. 相似文献
84.
随着农作物种质资源数量的不断增加,种质资源交流的日益频繁以及种质资源利用的逐步深入,农作物种质资源数据库的建设对农作物的应用研究和基础性研究至关重要。上海市农业生物基因中心借助于本中心保存的近21万份种质资源的信息,开发了一套上海农作物种质资源数据库,本文主要阐述了该数据库设计和构建的目的、原则和数据库的架构、运行环境以及主要功能模块。上海农作物种质资源数据库采用了B/S结构,平台系统利用多层逻辑架构实现了对农作物种质资源数据信息的收集、存储、查询、统计分析等功能。外部用户通过浏览器即可访问平台系统,浏览查询种质资源信息。内部管理员可使用平台的受限功能,需要认证成功后才可使用后台管理功能,实现对整个平台数据的管理。注册用户还可通过基因资源数据库提交引种申请,管理员结合管理信息系统实现对外供种全流程的网络化,借此可提高工作效率,增加工作流程的透明度。 相似文献
85.
Qing‐Ping Zhao Jin‐Dong Zhu Nan‐Nan Li Xiao‐Nan Wang Xiang Zhao Xiao Zhang 《植物学报(英文版)》2020,62(5):614-630
Both phototropins(phot1 and phot2) and cryptochromes(cry1 and cry2) were proven as the Arabidopsis thaliana blue light receptors. Phototropins predominately function in photomovement, and cryptochromes play a role in photomorphogenesis. Although cryptochromes have been proposed to serve as positive modulators of phototropic responses, the underlying mechanism remains unknown. Here, we report that depleting sucrose from the medium or adding gibberellic acids(GAs) can partially restore the defects in phototropic curvature of the phot1 phot2 double mutants under high-intensity blue light; this restoration does not occur in phot1 phot2 cry1 cry2 quadruple mutants and nph3(nonphototropic hypocotyl 3) mutants which were impaired phototropic response in sucrose-containing medium. These results indicate that GAs and sucrose antagonistically regulate hypocotyl phototropism in a cryptochromes dependent manner, but it showed a crosstalk with phototropin signaling on NPH3.Furthermore, cryptochromes activation by blue light inhibit GAs synthesis, thus stabilizing DELLAs to block hypocotyl growth, which result in the higher GAs content in the shade side than the lit side of hypocotyl to support the asymmetric growth of hypocotyl. Through modulation of the abundance of DELLAs by sucrose depletion or added GAs, it revealed that cryptochromes have a function in mediating phototropic curvature. 相似文献
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The aim of the present study was to investigate the tolerance of five new Achromobacter and Pseudomonas strains to kerosene and to establish if the production of several secondary metabolites increases or not when these bacteria were grown in the presence of kerosene. The biodegradation of kerosene by isolated bacteria was also investigated in this study. Five Proteobacteria were isolated from different samples polluted with petroleum and petroleum products. Based on their morphological, biochemical, and molecular characteristics, isolated bacteria were identified as Achromobacter spanius IBBPo18 and IBBPo21, Pseudomonas putida IBBPo19, and Pseudomonas aeruginosa IBBPo20 and IBBPo22. All these bacteria were able to tolerate and degrade kerosene. Higher tolerance to kerosene and degradation rates were observed for P. aeruginosa IBBPo20 and IBBPo22, compared with that observed for A. spanius IBBPo18 and IBBPo21, and P. putida IBBPo19. All these bacteria were able to produce several secondary metabolites, such as surfactants and pigments. Glycolipid surfactants produced by P. aeruginosa IBBPo20 and IBBPo22, A. spanius IBBPo18 and IBBPo21, and P. putida IBBPo19 have a very good emulsification activity, and their activity increased when they were grown in the presence of kerosene. The production of rhamnolipid surfactants by P. aeruginosa IBBPo20 and IBBPo22 was confirmed by detection of rhlAB gene involved in their biosynthesis. Pyocyanin and pyoverdin pigments were produced only by P. aeruginosa IBBPo20 and IBBPo22, while carotenoid pigments were produced by all the isolated bacteria. Significant changes in pigments production were observed when P. aeruginosa IBBPo20 and IBBPo22, A. spanius IBBPo18 and IBBPo21, and P. putida IBBPo19 were grown in the presence of kerosene. Due to their ability to tolerate and degrade kerosene, and also to produce several secondary metabolites, the isolated bacteria could be used in the bioremediation of kerosene-polluted environments. 相似文献
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89.
Weixiang He Jianmin Liu Daoquan Liu Jundong Hu Ye Jiang Mingzhou Li Qian Wang Ping Chen Guang Zeng Deqiang Xu Xinghuan Wang Michael E. DiSanto Xinhua Zhang 《Journal of cellular and molecular medicine》2020,24(24):14280
To explore how alterations in the phosphodiesterase type 5 (PDE5) signalling pathway and oxidative stress correlate with changes in the expression of relaxation and contraction molecules and erectile dysfunction (ED) in the corpus cavernosum smooth muscle (CCSM) of spontaneously hypertensive rats (SHR). In this study, SHR and Wistar‐Kyoto (WKY) rats were used. Erectile function was determined by apomorphine test and electrical stimulation (ES) of cavernous nerve. Masson''s trichrome staining and confocal microscopy were performed. Nitric oxide synthase (NOS), PDE5, phosphorylated‐PDE5 and α1‐adrenergic receptor (α1AR) were determined by RT‐PCR and Western blotting while oxidative stress in CC was determined by colorimetric analysis. SHR exhibited obvious ED. CC of SHR showed less SM but more collagen fibres. The expression of NOS isoforms in SHR was significantly decreased while all α1AR isoforms were increased. In addition, PDE5 and phosphorylated‐PDE5 were down‐regulated and its activity attenuated in the hypertensive rats. Meanwhile, the SHR group suffered oxidative stress, which may be modulated by endoplasmic reticulum stress and NADPH oxidase up‐regulation. Dysregulation of NOS and α1AR, histological changes and oxidative stress in CC may be associated with the pathophysiology of hypertension‐induced ED. In addition, PDE5 down‐regulation may lead to the decreased efficacy of PDE5 inhibitors in some hypertensive ED patients and treatment of oxidative stress could be used as a new therapeutic target for this type of ED. 相似文献
90.
Xi Jin Tianhai Lin Guang Yang Huawei Cai Bo Tang Xinyang Liao Huifang Li Xiaoting Chen Lina Gong Hang Xu Yi Sun Ping Tan Jianqiong Yin Hongwen Ma Jianzhong Ai Kunjie Wang Qiang Wei Lu Yang Hong Li 《Journal of cellular and molecular medicine》2020,24(9):5082-5096
Benign prostatic hyperplasia (BPH) occurs most commonly among older men, often accompanied by chronic tissue inflammation. Although its aetiology remains unclear, autoimmune dysregulation may contribute to BPH. Regulatory T cells (Tregs) prevent autoimmune responses and maintain immune homeostasis. In this study, we aimed to investigate Tregs frequency, phenotype, and function in BPH patients and to evaluate adoptive transfer Tregs for immunotherapy in mice with BPH via CD39. Prostate specimens and peripheral blood from BPH patients were used to investigate Treg subsets, phenotype and Treg‐associated cytokine production. Sorted CD39+/? Tregs from healthy mice were adoptively transferred into mice before or after testosterone propionate administration. The Tregs percentage in peripheral blood from BPH patients was attenuated, exhibiting low Foxp3 and CD39 expression with low levels of serum IL‐10, IL‐35 and TGF‐β. Immunohistochemistry revealed Foxp3+ cells were significantly diminished in BPH prostate with severe inflammatory. Although the Tregs subset was comprised of more effector/memory Tregs, CD39 was still down‐regulated on effector/memory Tregs in BPH patients. Before or after testosterone propionate administration, no alterations of BPH symptoms were observed due to CD39‐ Tregs in mice, however, CD39+Tregs existed more potency than Tregs to regulate prostatic hyperplasia and inhibit inflammation by decreasing IL‐1β and PSA secretion, and increasing IL‐10 and TGF‐β secretion. Furthermore, adoptive transfer with functional Tregs not only improved prostate hyperplasia but also regulated muscle cell proliferation in bladder. Adoptive transfer with Tregs may provide a novel method for the prevention and treatment of BPH clinically. 相似文献