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91.
汶川地震救援人员创伤后应激反应特征的初步研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:探讨5.12汶川地震军队救援人员创伤后应激损伤状况。方法:采用创伤后压力诊断量表、焦虑自评量表、抑郁自评量表和匹兹堡睡眠质量问卷,在地震爆发后65天左右,对107名执行运输遗体任务的官兵进行了测量。结果:PTSD症状轻度的占84%,中重度的占15%。其中症状在1个月内消失的占63%。从症状的分布来看,闯入性回忆占36.4%,回避29.9%,过度警觉29.9%,焦躁不安或易怒37.4%,入睡困难、睡眠易醒或早醒43.9%,难以集中注意力45.8%,对重要的活动兴趣下降32.7%。救援人员抑郁症状得分低于全国常模水平;焦虑自评量表得分与全国常模差异不显著。睡眠质量差的占72%,以入睡时间长和日间功能降低为主。结论:担任遗体运输的救援官兵在救援早期普遍存在创伤后应激反症状,症状程度较轻,多数在1个月内消失,焦虑和抑郁症状水平的总体状况也比较低,但普遍存在睡眠质量差的问题,并且直接影响到日间功能。  相似文献   
92.
佛坪国家级自然保护区植被垂直带谱及其与邻近地区的比较   总被引:10,自引:0,他引:10  
在首先确定垂直带划分的原则和将佛坪自然保护区植被划分为落叶阔叶林带、中山小叶林带和亚高山针叶林带3个垂直带,各垂直带植被物种组成的区系、生活型组成和物种多样性的差异证实了这种划分的合理性。与邻近地区植被垂直带谱的比较表明,佛坪自然保护区的植被垂直带谱与秦岭北坡有明显差异,表现为典型的暧温带与北亚热带过渡区域的植被景观,虽然基带以上各植被带暖温带特色很明显,但其植被属性应是北亚热带的。  相似文献   
93.
该研究采用同源克隆与PCR扩增方法,从马铃薯品种‘Desiree’中克隆植物磺肽素受体基因StPSKR1和StPSKR2的全长cDNA,并对其进行生物信息学分析及亚细胞定位分析,为深入研究StPSKR1和StPSKR2基因在马铃薯生长发育和生物胁迫中的作用提供理论依据。结果发现:(1)通过同源克隆与PCR扩增获得StPSKR1和StPSKR2的全长cDNA片段,并将其克隆到pGWB5-GFP载体;测序结果显示这2个基因编码的蛋白质与数据库给定的蛋白质序列保持一致,表明成功克隆到StPSKR1和StPSKR2基因。(2)StPSKR1位于马铃薯1号染色体上,cDNA全长3 042 bp,编码1 013个氨基酸,预测蛋白相对分子质量为112.16 kD,理论等电点6.27;StPSKR2位于7号染色体,cDNA全长3 135 bp,编码1 044个氨基酸,相对分子量为114.99 kD,理论等电点6.19。(3)生物信息学分析显示,StPSKR1和StPSKR2都属于跨膜蛋白。(4)亚细胞定位结果显示,StPSKR1和StPSKR2均定位于细胞膜上。  相似文献   
94.
The treatment capacity of an integrated constructed wetland system (CWS) that was designed to reduce nitrogen (N) from secondary effluent was explored. The integrated CWS consisted of vertical-flow constructed wetland, floating bed and sand filter. The vertical-flow wetland was filled with gravel, steel slag and peat from the bottom to the top. Vetiver zizanioides was selected to grow in the vertical-flow constructed wetland and Coix lacrymajobi L. was grown in the floating bed. The results showed that the integrated CWS displayed superior removal efficiency for nitrate nitrogen (NO3-N), ammonia nitrogen (NH4+-N), nitrite nitrogen (NO2-N), and total nitrogen (TN). The average NO3-N, NO2-N, NH4+-N and TN removal efficiencies of the integrated CWS were 98.83%, 95.60%, 98.05% and 92.41%, respectively, during the whole experimental operation. The integrated CWS may have a good potential for removing N from secondary effluent.  相似文献   
95.
中药有效成分治疗类风湿关节炎研究进展   总被引:3,自引:0,他引:3  
中药治疗类风湿性关节炎(RA)有几千年的临床应用历史,积累了丰富的经验.近年来,国内外针对中药复方和单味药的抗RA作用开展了大量的实验研究工作,很多中药的活性成分(组分)和作用机制得到初步阐明,开发出青藤碱注射液、雷公藤多苷片和白芍总苷片等新型RA治疗药物.本文对中药有效成分在治疗RA方面的研究进展进行综述.  相似文献   
96.

Aims/hypothesis

The actions of peripherally administered nesfatin-1 on glucose homeostasis remain controversial. The aim of this study was to characterize the mechanisms by which peripheral nesfatin-1 regulates glucose metabolism.

Methods

The effects of nesfatin-1 on glucose metabolism were examined in mice by continuous infusion of the peptide via osmotic pumps. Changes in AKT phosphorylation and Glut4 were investigated by Western blotting and immnuofluorescent staining. Primary myocytes, adipocytes and hepatocytes were isolated from male mice.

Results

Continuous peripheral infusion of nesfatin-1 altered glucose tolerance and insulin sensitivity in mice fed either normal or high fat diet, while central administration of nesfatin-1 demonstrated no effect. Nesfatin-1 increases insulin secretion in vivo, and in vitro in cultured min6 cells. In addition, nesfatin-1 up-regulates the phosphorylation of AKT in pancreas and min6 islet cells. In mice fed normal diet, peripheral nesfatin-1 significantly increased insulin-stimulated phosphorylation of AKT in skeletal muscle, adipose tissue and liver; similar effects were observed in skeletal muscle and adipose tissue in mice fed high fat diet. At basal conditions and after insulin stimulation, peripheral nesfatin-1 markedly increased GLUT4 membrane translocation in skeletal muscle and adipose tissue in mice fed either diet. In vitro studies showed that nesfatin-1 increased both basal and insulin-stimulated levels of AKT phosphorylation in cells derived from skeletal muscle, adipose tissue and liver.

Conclusions

Our studies demonstrate that nesfatin-1 alters glucose metabolism by mechanisms which increase insulin secretion and insulin sensitivity via altering AKT phosphorylation and GLUT 4 membrane translocation in the skeletal muscle, adipose tissue and liver.  相似文献   
97.
spindlin1, a novel human gene recently isolated by our laboratory, is highly homologous to mouse spindlin gene. In this study, we cloned cDNA full-length of this novel gene and send it to GenBank database as spindlin1 (Homo sapiens spindlin1) with Accession No. AF317228. In order to investigate the function of spindlin1, we studied further the subcellular localization of Spindlin1 protein and the effects of spindlin1 overexpression in NIH3T3 cells. The results showed that the fusion protein pEGFP-N1-spindlin1 was located in the nucleus and the C-terminal is correlated with nuclear localization of Spindlin1 protein. NIH3T3 cells which could stably express spindlin1 as a result of RT-PCR analysis compared with the control cells displayed a complete morphological change; made cell growth faster; and increased the percentage of cells in G2/M and S phase. Furthermore, overexpressed spindlin1 cells formed colonies in soft agar in vitro and formed tumors in nude mice. Our findings provide direct evidence that spindlin1 gene may contribute to tumorigenesis.  相似文献   
98.
罗勤  张晓莉  李兵  冯爱平  钱跃 《微生物学报》2008,35(2):0275-0280
单核细胞增生李斯特菌 (Listeria monocytogenes LM) 属于典型的细胞内寄生革兰氏阳性菌, 是WHO公布的四大食源性致病菌之一。LM不仅是人畜共患传染病李斯特菌病 (listeriosis) 的主要病原菌, 也是研究胞内感染和细胞介导的免疫应答的模式细菌。绝大多数LM毒力基因的转录表达受到PrfA蛋白的调控。本文简单介绍了LM侵染宿主细胞必需的毒力基因及其产物; 重点对毒力基因调节蛋白PrfA的结构和功能, PrfA调节毒力基因表达的主要方式最新进展进行了综述和讨论。  相似文献   
99.
可溶性TRAIL蛋白的高密度培养及补料策略研究   总被引:3,自引:0,他引:3  
采用分批补料的方法高密度培养重组大肠杆菌C600/PbvTRAIL制备人可溶性TRAIL蛋白,优化发酵工艺,探索简单高效的分离纯化方法并测定蛋白生物活性。通过比较几种不同的补料策略:间歇流加、Dostat、pHstat,摸索了一种流加策略,即DOstatpHstat组合流加,有效的避免了发酵过程中,尤其是诱导表达阶段乙酸积累的增加,使TRAIL蛋白在高密度培养条件下,得到高效表达。菌体密度最终达到300g/L(WCW)以上,可溶性TRAIL蛋白占菌体总蛋白的4.2%,含量为1.1g/L。在整个发酵过程中,乙酸浓度接近于0,且未使用任何特殊手段,如纯氧、加压等,简化了发酵工艺,降低了发酵成本,为TRAIL的工业化生产创造了条件。  相似文献   
100.
HUPO initiated the Plasma Proteome Project (PPP) in 2002. Its pilot phase has (1) evaluated advantages and limitations of many depletion, fractionation, and MS technology platforms; (2) compared PPP reference specimens of human serum and EDTA, heparin, and citrate-anti-coagulated plasma; and (3) created a publicly-available knowledge base (www.bioinformatics.med.umich.edu/hupo/ppp; www.ebi.ac.uk/pride). Thirty-five participating laboratories in 13 countries submitted datasets. Working groups addressed (a) specimen stability and protein concentrations; (b) protein identifications from 18 MS/MS datasets; (c) independent analyses from raw MS-MS spectra; (d) search engine performance, subproteome analyses, and biological insights; (e) antibody arrays; and (f) direct MS/SELDI analyses. MS-MS datasets had 15 710 different International Protein Index (IPI) protein IDs; our integration algorithm applied to multiple matches of peptide sequences yielded 9504 IPI proteins identified with one or more peptides and 3020 proteins identified with two or more peptides (the Core Dataset). These proteins have been characterized with Gene Ontology, InterPro, Novartis Atlas, OMIM, and immunoassay-based concentration determinations. The database permits examination of many other subsets, such as 1274 proteins identified with three or more peptides. Reverse protein to DNA matching identified proteins for 118 previously unidentified ORFs. We recommend use of plasma instead of serum, with EDTA (or citrate) for anticoagulation. To improve resolution, sensitivity and reproducibility of peptide identifications and protein matches, we recommend combinations of depletion, fractionation, and MS/MS technologies, with explicit criteria for evaluation of spectra, use of search algorithms, and integration of homologous protein matches. This Special Issue of PROTEOMICS presents papers integral to the collaborative analysis plus many reports of supplementary work on various aspects of the PPP workplan. These PPP results on complexity, dynamic range, incomplete sampling, false-positive matches, and integration of diverse datasets for plasma and serum proteins lay a foundation for development and validation of circulating protein biomarkers in health and disease.  相似文献   
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