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1.
本文报道了寄生在云杉上的中国新记录种顶裂盘菌(Lophophacidium hyperboreumLagerb.);首次发现了这个种的无性型座壳梭孢属(Apostrasseria sp.),证实了融雪前病株针叶上有表生的菌丝和小菌核;查清了它是新疆云杉林中的广布种,引致云杉雪枯病;发现了新分布区,地理分布范围在75°—94°E,37°40′—49°N;发现了新寄主,多土的西伯利亚云杉(Picea obovata Ledeb.)和引进的青海云杉(P.crassifolia Kom.)、川西云杉(P.balfourianaRehd.et Wils.)。  相似文献   
2.
Yu  Yifei  Hou  Kun  Ji  Tong  Wang  Xishu  Liu  Yining  Zheng  Yangyang  Xu  Jinying  Hou  Yi  Chi  Guangfan 《Molecular and cellular biochemistry》2021,476(5):2111-2124
Molecular and Cellular Biochemistry - MicroRNAs (miRNA), endogenous non-coding RNAs approximately 22 nucleotides long, regulate gene expression by mediating translational inhibition or mRNA...  相似文献   
3.
The antineoplastic target aldo–keto reductase family member 1B10 (AKR1B10) and the critical polyol pathway enzyme aldose reductase (AKR1B1) share high structural similarity. Crystal structures reported here reveal a surprising Trp112 native conformation stabilized by a specific Gln114-centered hydrogen bond network in the AKR1B10 holoenzyme, and suggest that AKR1B1 inhibitors could retain their binding affinities toward AKR1B10 by inducing Trp112 flip to result in an “AKR1B1-like” active site in AKR1B10, while selective AKR1B10 inhibitors can take advantage of the broader active site of AKR1B10 provided by the native Trp112 side-chain orientation.  相似文献   
4.

Background

Stroke is the second most common cause of mortality in China. Although most subtypes of ischemic stroke share similar risk factors, they have different etiologies. Our study aimed to evaluate the different risk factor profiles between the stroke subtypes, lacunar infarcts (LI) and large-artery atherosclerosis (LAA), and clarify the characteristics of current acute ischemic stroke in China.

Methods

In this cross-sectional study, we analyzed the clinical characteristics of 1982 patients with acute ischemic stroke who were admitted to the neurology department at the Peking University First Hospital between 2007 and 2014. Ischemic stroke was further classified into LAA, LI, cardioembolism (CE) and undetermined causes of infarction (UDI) according to TOAST classification. Demographic characteristics, risk factors, as well as the findings of laboratory and imaging tests of 1773 patients with LAA and LI, were analyzed by univariate and multivariate logistic analysis.

Results

Of the 1982 ischemic stroke patients included in this study, 1207 were diagnosed with LAA, 566 with LI, 173 with cardioembolism (CE) and 36 with undetermined causes of infarction (UDI). By comparing the risk factors in multivariate logistic regression analysis, hypertension [odds ratio (OR) = 1.832] and white matter leukoaraiosis (WML) (OR = 1.865) were found to be more strongly correlated with LI than LAA. Low density lipoprotein- cholesterol (LDL-c) (OR = 0.774) were more strongly related to LAA than LI.

Conclusions

This study found that hypertension and WML were more strongly correlated with LI than LAA. LDL-c was more strongly related to LAA than LI.  相似文献   
5.
6.
漆酶及其应用的研究进展   总被引:5,自引:1,他引:5  
漆酶是一种含铜的多酚氧化酶,白腐真菌普遍能分泌该酶.有氧条件下,漆酶能催化多种高分子化合物降解,利用该性质漆酶已经广泛应用于生物制浆、污染物生物降解、生物漂白等领域.介绍了目前漆酶在农业和工业各个领域中的应用.  相似文献   
7.
8.
王宏亮  高艺宁  王振宇  沙威  吴健生 《生态学报》2020,40(23):8504-8515
生态系统服务是人类赖以生存和发展的基础,开展城市生态系统服务评估并对生态管理单元实行分区管控有助于人居环境的改善。针对高度城市化地区生态系统服务的功能特征,采用生态系统服务价值当量测算不同用地类型的生态系统服务价值。研究从生态功能和经济功能2个方面构建生态系统服务指标体系,对2017年深圳市666个社区单元的生态系统服务价值进行评估;运用空间自相关分析方法,依据局部空间自相关的集聚特征叠加产生的组合类型,划分不同社区生态管理单元,并提出生态分区管控策略。研究结果表明:(1)生态系统服务价值评估便于高度城市化地区城市生态系统服务功能的整体评价。(2)2017年深圳市生态系统服务价值空间差异明显,呈现东部高、中西部低的空间格局。深圳市生态系统服务总价值约583.96亿元,最高值为大鹏新区的160.25亿元,最低值为福田区的13.24亿元。(3)将深圳市666个社区单元划分为4类城市生态管理分区,并采用差异化的分区管控措施,表明有效的城市生态管理分区能够兼顾各项生态系统服务功能并实现功能效益的最优化。该研究结果可为区域生态系统服务精细化管理和生态治理差异化管控提供借鉴。  相似文献   
9.
Angiotensin (ANG) II receptors have been reported in the nonpigmented ciliary epithelium (NPE) of the eye. In cultured NPE, we found ANG II caused a dose-dependent rise of cytoplasmic sodium. The sodium increase was inhibited by the AT(1)-AT(2) receptor antagonist saralasin (IC(50) = 3.7 nM) and the AT(1) antagonist losartan (IC(50) = 0.6 nM) but not by the AT(2) antagonist PD-123319. ANG II also caused a dose-dependent increase in the rate of ouabain-sensitive (86)Rb uptake. The ANG II-induced cell sodium increase and (86)Rb uptake increase were reduced by dimethylamiloride (DMA; 10 microM). On the basis of this finding, we propose that Na(+)/H(+) exchange is stimulated by ANG II. Simultaneously, ANG II appears to inhibit H(+)-ATPase-mediated proton export. Thus Ang II (10 nM) did not alter the baseline cytoplasmic pH (pH(i)) but reduced pH(i) in cells that were also exposed to 10 microM DMA. Consistent with the notion of H(+)-ATPase inhibition in ANG II-treated NPE, bafilomycin A(1) (100 nM) (BAF) and ANG II were both observed to suppress the pH(i) increase that occurs upon exposure to a mixture of epinephrine (1 microM) and acetylcholine (10 microM) and the pH(i) increase elicited by depolarization. In ATP hydrolysis measurements, H(+)-ATPase activity (bafilomycin A(1)-sensitive ATP hydrolysis) was reduced significantly in cells that had been pretreated 10 min with 10 nM ANG II. In summary, these studies suggest that ANG II causes H(+)-ATPase inhibition and an increase of cell sodium due to activation of Na(+)/H(+) exchange.  相似文献   
10.
目的探讨子宫脱垂(uterine prolapse,UP)患者阴道前壁中Fibulin-3 mRNA和蛋白的表达及其与子宫脱垂临床因素的关系。方法应用免疫组织化学S-P法及RT-PCR法对50例子宫脱垂患者的阴道前壁组织中Fibulin-3蛋白及mRNA水平表达进行测定,并与对照组20例(宫颈上皮内瘤变或妇科良性肿瘤行经阴道子宫全切术的非脱垂患者)组织对比,结合子宫脱垂的临床参数进行分析。结果免疫组化结果显示子宫脱垂组织中Fibulin-3蛋白表达的阳性率为52.0%(26/50),明显低于对照组85.0%(17/20),III+Ⅳ度子宫脱垂患者阴道前壁Fibulin-3蛋白阳性表达率明显低于I+II度子宫脱垂组(P=0.009),伴有压力性尿失禁(SUI)的子宫脱垂患者Fibulin-3蛋白表达较无SUI患者明显下降(P=0.004)。RT-PCR结果显示子宫脱垂患者阴道前壁组织中Fibulin-3 mRNA的相对表达量较对照组明显降低,且其含量与子宫脱垂的严重程度及是否伴有SUI相关,差异具有统计学意义。Fibulin-3蛋白和mRNA表达与患者阴道分娩次数无关(P值均〉0.05)。结论Fibulin-3蛋白和mRNA在子宫脱垂患者阴道前壁组织中存在低表达,并与子宫脱垂的严重程度以及是否伴有SUI密切相关,Fibulin-3可能在子宫脱垂的发生发展中起重要的作用。  相似文献   
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