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101.
为进一步明确香蕉叶斑病菌喙突脐蠕孢的生物学特性,调查了部分环境因素(碳氮源、植物成分培养基)对供试菌株(CLER09、D087和JL05)的营养生长和产孢的影响。结果显示,分生孢子主要先从基部萌芽,在28℃下约培养10h后出现两端萌芽;供试菌株对测试的20种碳源及26种氮源显示相似的生长反应,均可利用除菊糖外的测试碳源及氮源进行营养生长和产孢;测试的6种植物成分培养基对供试菌株的营养生长效果皆优于PDA培养基;除燕麦培养基外,其余5种培养基对菌株CLER09和D087的产孢作用均优于PDA培养基;测试的6种培养基对菌株JL05的产孢作用均优于PDA培养基。不同植物成分培养基对该菌分生孢子形态影响较大,以米糠、象草培养基对菌株D087和JL05的分生孢子长度和玉米粉培养基对菌株CLER09的分生孢子宽度的增长效果最为明显。 相似文献
102.
受磷蛋白(phospholamban)是心肌收缩的一个重要调节因子,可抑制心肌肌浆网钙ATPase的活性、降低其对钙的亲和力。正常情况下,受磷蛋白可被不同的蛋白激酶磷酸化从而解除其肌浆网钙ATPase的抑制作用。国外两个DCM家系研究发现受磷蛋白基因突变与DCM的发生有关,研究目的旨在探讨中国人群心肌特异性受磷蛋白基因突变与特发性扩张型心肌病发病的关系。收集60例确诊的特发性扩张型心肌病患者临床资料,采集血样本并分离白细胞和提取基因组DNA。应用PCR扩增肌特异性受磷蛋白基因片段,经测序检测基因突变的存在。结果显示60例扩张型心肌病人受磷蛋白基因开放阅读框未发现突变,仅有两例患者出现阅读框3′部分非翻译区分别离终止密码153和173位单个碱基T的缺失。两例患者终止密码后非翻译区单个碱基T的缺失据分析并无实际意义。因此我们认为绝大部分中国人扩张型心肌病的发病可能与受磷蛋白基因突变无关。Abstract: Phospholamban (PLB) is a prominent regulator of myocardial contractility and a reversible inhibitor of the cardiac sarcoplasmic reticulum Ca2+ ATPase activity. In normal cardiac muscles, phospholamban can be phosphorylated at distinct sites by various protein kinases and release its inhibition to sarcoplasmic reticulum Ca2+ ATPase. The studies of pedigrees have shown dilated cardiomyopathy (DCM) is related with mutation of PLB. The aim of present study is to investigate the relationship between mutation of PLB gene and DCM. Sixty patients with idiotic DCM were enrolled in present study. The clinical data were collected, including clinical symptoms, ECG and echocardiography. Peripheral blood samples of all these subjects were collected to extract genome DNA. The fragments of PLB gene were amplified by PCR and PCR fragment sequencing was performed to study weather mutation of phospholamban gene exists. phospholamban gene did not show any mutation in these patients. Most Chinese DCM patients may not be related with mutation of PLB gene. 相似文献
103.
Jing-Shu Zhang Shu-Jing Zhang Qian Li Ying-Hua Liu Ning He Jing Zhang Peng-Hui Zhou Min Li Tong Guan Jia-Ren Liu 《PloS one》2015,10(3)
Tocotrienols have been shown many biologic functions such as antioxidant, anti-cancer, maintaining fertility and regulating the immune system and so on. In this study, after feeding with tocotrienol-rich fraction from palm oil (TRF) for 2 weeks, Balb/c nude mice were inoculated human colon SW620 cancer cell and then continued to feed TRF for 4 weeks. At termination of experiments, xenografts were removed and determined the expression of Wnt-pathways related protein by immunohistochemistry or western blotting. Liver tissues were homogenated for determining the levels of antioxidative enzymes activity or malondialdehyde (MDA). The results showed that TRF significantly inhibited the growth of xenografts in nude mice. TRF also affected the activity of antioxidative enzymes in the liver tissue of mice. These changes were partly contributed to activation of wnt pathways or affecting their related protein. Thus, these finding suggested that the potent anticancer effect of TRF is associated with the regulation of Wnt signal pathways. 相似文献
104.
Chen Xie Hou Cai-Lan Wang Shi-Bin Huang Zhuo-Hui Huang Ying-Hua Li Xue-Li Jia Fu-Jun 《Sleep and biological rhythms》2020,18(3):225-232
Sleep and Biological Rhythms - To examine whether insomnia disorder is associated with cognitive impairment in young and middle-aged Chinese adults. A case–control sample of 98... 相似文献
105.
Ying-Hua Chu Fa-Hsuan Lin Yu-Jen Chou Kevin W.-K. Tsai Wen-Jui Kuo Iiro P. J??skel?inen 《PloS one》2013,8(11)
Seeing the articulatory gestures of the speaker (“speech reading”) enhances speech perception especially in noisy conditions. Recent neuroimaging studies tentatively suggest that speech reading activates speech motor system, which then influences superior-posterior temporal lobe auditory areas via an efference copy. Here, nineteen healthy volunteers were presented with silent videoclips of a person articulating Finnish vowels /a/, /i/ (non-targets), and /o/ (targets) during event-related functional magnetic resonance imaging (fMRI). Speech reading significantly activated visual cortex, posterior fusiform gyrus (pFG), posterior superior temporal gyrus and sulcus (pSTG/S), and the speech motor areas, including premotor cortex, parts of the inferior (IFG) and middle (MFG) frontal gyri extending into frontal polar (FP) structures, somatosensory areas, and supramarginal gyrus (SMG). Structural equation modelling (SEM) of these data suggested that information flows first from extrastriate visual cortex to pFS, and from there, in parallel, to pSTG/S and MFG/FP. From pSTG/S information flow continues to IFG or SMG and eventually somatosensory areas. Feedback connectivity was estimated to run from MFG/FP to IFG, and pSTG/S. The direct functional connection from pFG to MFG/FP and feedback connection from MFG/FP to pSTG/S and IFG support the hypothesis of prefrontal speech motor areas influencing auditory speech processing in pSTG/S via an efference copy. 相似文献
106.
麦长管蚜的抗药性研究 总被引:12,自引:0,他引:12
麦蚜在我国分布广、为害重,又传播病毒病,是小麦的重要害虫。近年麦蚜的发生为害有增长的趋势,有些地方反映农药防效下降、用药次数增加。本文介绍1983—1987年5年中采用6个省市的8个地区麦蚜种群对6种农药进行了点滴法毒力测定。探明了张掖和高台麦长管蚜[sitobion avenae (Fab.)]对氧化乐果产生10—15倍抗药性。用英国Rothamsted试验站的比色板试验法进行生化测定,结果同生物测定一致。作者认为该法是一种探测蚜虫抗药性简便可行的定性方法。用北京室内饲养的麦长管蚜以16种新老农药品种用点滴法进行了敏感水平测定,建立了麦长管蚜对16种供试农药的毒力基线。这对探测麦蚜抗药性、监测其抗药性动态变化打下一定基础。通过室内毒力测定、田间药效试验和20多万亩的大面积示范推广,作者提出杀螟松是防治麦蚜较理想的候选农药品种,以替换当前使用的药效已下降的乐果和氧化乐果、替换当前使用的毒性很高的杀虫剂甲胺磷。 相似文献
107.
在21世纪头20年里,呼吸道病毒造成的地区性乃至世界性的流行已经发生多次,而疫情的暴发严重威胁人类健康与生存,但临床上,仍缺乏针对病毒的特异性治疗手段。随着肠道微生态相关研究的广泛开展,肠道菌群在哮喘,纤维化及细菌性感染等多种肺部疾病的发病及防治中发挥着重要作用,成为"肠-肺轴"的关键枢纽。病毒性肺炎与肠道微生态间也存在着紧密的相互联系,通过改善肠道菌群,对呼吸病毒感染具有较好的防治作用。其内在机制主要涉及到:通过增强肠道黏膜屏障功能、减少继发性细菌的感染;通过菌体成分或者代谢产物如短链脂肪酸,色氨酸代谢产物等提高固有样淋巴细胞(Innate lymphoid cells,ILC)、单核-巨噬细胞、树突状细胞、自然杀伤细胞(Natural killer,NK)、粒细胞等固有免疫细胞的抗病毒免疫功能及调节Th17/Treg平衡抑制过度的炎症反应等。本文将系统回顾已发表的文章,对肠道菌群在病毒性肺炎方面的研究作系统的阐述,以求为研究者在病毒性肺炎的机制探究和防治方面提供帮助。 相似文献
108.
109.
Wei Zhu Lai-Xing Wang Dan-Ye Chen Ying-Hua Gao Yi-Jia Yan Xiao-Feng Wu Mi Wang Yi-Ping Han Zhi-Long Chen 《Bioorganic & medicinal chemistry letters》2018,28(16):2784-2788
Three novel 173-dicarboxylethyl-pyropheophorbide-a amide derivatives as photosensitizers for photodynamic therapy (PDT) were synthesized from pyropheophorbide-a (Ppa). Their photophysical and photochemical properties, intracellular localization, photocytotoxicity in vitro and in vivo were investigated. All target compounds exhibited low cytotoxicity in the dark and remarkable photocytotoxicity against human esophageal cancer cells. Among them, 1a showed highest singlet oxygen quantum yield. Upon light activation, 1a exhibited significant photocytotoxicity. After PDT treatment, the growth of Eca-109 tumor in nude mice was significantly inhibited. Therefore, 1a is a powerful and promising antitumor photosensitizer for PDT. 相似文献
110.
目的:探讨依达拉奉联合红花黄色素对急性脑梗死(ACI)患者神经功能、血脂水平及血液流变学的影响。方法:选取2017年1月到2018年8月期间我院收治的ACI患者70例,采用数字表法将患者随机分为对照组(n=34)和研究组(n=36),对照组在常规治疗的基础上给予红花黄色素治疗,研究组在对照组基础上联合依达拉奉治疗,两组均治疗14d,比较两组治疗后的临床疗效,比较两组治疗前后的神经功能[美国国立卫生院卒中量表(NIHSS)评分、神经元特异性烯醇化酶(NSE)和S-100β水平]、血脂指标[甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)和高密度脂蛋白胆固醇(HDL-C)]及血液流变学(全血黏度低切、全血黏度中切、全血黏度高切、血浆黏度)情况,记录两组治疗期间发生的不良反应。结果:研究组治疗14 d后临床总有效率为91.67%(33/36),高于对照组患者的73.53%(25/34)(P0.05)。两组患者治疗14 d后NIHSS评分、NSE和S-100β水平较治疗前降低,且研究组低于对照组(P0.05)。两组患者治疗14 d后TG、TC、LDL-C均较治疗前降低,且研究组低于对照组(P0.05),HDL-C则较治疗前升高,且研究组高于对照组(P0.05)。两组患者治疗14 d后全血黏度低切、全血黏度中切、全血黏度高切、血浆黏度均较治疗前降低,且研究组低于对照组(P0.05)。两组不良反应发生率比较无差异(P0.05)。结论:依达拉奉联合红花黄色素治疗ACI患者安全有效,可显著改善患者神经功能、血脂水平及血液流变学情况,临床应用价值较高。 相似文献