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971.
徐涛 《生物化学与生物物理进展》2014,41(10):925-925
正《生物化学与生物物理进展》(以下简称《进展》)创刊于1974年,作为记录科学成果的载体和促进科学交流的平台,它经历了中国科学研究从艰难起步到蓬勃发展的重要时期,是我国科学事业发展的见证者,也是其中重要的参与者.经过40年的艰苦努力,《进展》得到了很大的发展:已初步被国际学术界认知,被SCI、CA、俄罗斯文摘等国际检索系统收录;2009年起全部论文注册DOI,每年均收到海外学者的直接投稿;同时,《进展》被国内生物 相似文献
972.
目的 探讨规范化培训与量化绩效考核对手术室感染率的影响。方法 2012年1—12月对我院手术室护理人员进行规范化培训并实施量化绩效考核,与2011年1—12月感染率情况进行比较。结果 对手术室护理人员规范化培训,采取量化绩效考核之后,手术室感染率由1.46%下降到0.70%(P=0.001)。结论 在护理管理中对护理人员进行规范化培训,并绩效考核量化其工作内容,能够调动其工作积极性,降低手术室感染率并提高护理服务质量。 相似文献
973.
974.
目的
了解广东省三级医院护
理人力资源的配置现状,探讨更合理的配置对策。方法 自行设计问卷,对广东省21个地市的76所三级医院护理人力资源数量、护理人力资源内部结构、人员流失、支持保障系统情况等现状进行研究分析。结果 8所(13.33%)医院未成立临床支持中心; 23所(38.33%)医院普通病房实际床位总数与普通病房护士总数比不达标;职业性别比例严重失衡,男性仅占2.61%;34岁及以下护士占76.38%;大专及以下学历占78.61%;高级职称占4.65%;近年离职比由3.62%上升至5.08%。结论 广东省三级医院护理人员非护理工作负担较重;人力资源总量相对不足,队伍结构欠合理;护士人力流失逐年增加。建议优化三级医院护理人力配置,重视临床服务指标,建立并完善后勤保障系统,积极开展护士岗位改革等是适应社会高速发展需求和护理学科专业化的重要举措。 相似文献
975.
Manish Sharma Sankar Bhattacharyya Minu Nain Manpreet Kaur Vikas Sood Vishal Gupta Renu Khasa Malik Z Abdin Sudhanshu Vrati Manjula Kalia 《Autophagy》2014,10(9):1637-1651
Autophagy is a lysosomal degradative pathway that has diverse physiological functions and plays crucial roles in several viral infections. Here we examine the role of autophagy in the life cycle of JEV, a neurotropic flavivirus. JEV infection leads to induction of autophagy in several cell types. JEV replication was significantly enhanced in neuronal cells where autophagy was rendered dysfunctional by ATG7 depletion, and in Atg5-deficient mouse embryonic fibroblasts (MEFs), resulting in higher viral titers. Autophagy was functional during early stages of infection however it becomes dysfunctional as infection progressed resulting in accumulation of misfolded proteins. Autophagy-deficient cells were highly susceptible to virus-induced cell death. We also observed JEV replication complexes that are marked by nonstructural protein 1 (NS1) and dsRNA colocalized with endogenous LC3 but not with GFP-LC3. Colocalization of NS1 and LC3 was also observed in Atg5 deficient MEFs, which contain only the nonlipidated form of LC3. Viral replication complexes furthermore show association with a marker of the ER-associated degradation (ERAD) pathway, EDEM1 (ER degradation enhancer, mannosidase α-like 1). Our data suggest that virus replication occurs on ERAD-derived EDEM1 and LC3-I-positive structures referred to as EDEMosomes. While silencing of ERAD regulators EDEM1 and SEL1L suppressed JEV replication, LC3 depletion exerted a profound inhibition with significantly reduced RNA levels and virus titers. Our study suggests that while autophagy is primarily antiviral for JEV and might have implications for disease progression and pathogenesis of JEV, nonlipidated LC3 plays an important autophagy independent function in the virus life cycle. 相似文献
976.
Ásta Rós Sigtryggsdóttir Elena Papaleo Sigríður H. Thorbjarnardóttir Magnús M. Kristjánsson 《Biochimica et Biophysica Acta - Proteins and Proteomics》2014,1844(4):705-712
The subtilisin-like serine proteinases, VPR, from a psychrotrophic Vibrio species and aqualysin I (AQUI) from the thermophile Thermus aquaticus, are structural homologues, but differ significantly with respect to stability and catalytic properties. It has been postulated that the higher catalytic activity of cold adapted enzymes when compared to homologues from thermophiles, reflects their higher molecular flexibility. To assess a potential difference in molecular flexibility between the two homologous proteinases, we have measured their Trp fluorescence quenching by acrylamide at different temperatures. We also investigated protein dynamics of VPR and AQUI at an atomic level by molecular dynamics simulations. VPR contains four Trp residues, three of which are at corresponding sites in the structure of AQUI. To aid in the comparison, a Tyr at the fourth corresponding site in AQUI was mutated to Trp (Y191W). A lower quenching effect of acrylamide on the intrinsic fluorescence of the thermophilic AQUI_Y191W was observed at all temperatures measured (10–55 °C), suggesting that it possesses a more rigid structure than VPR. The MD analysis (Cα rmsf profiles) showed that even though VPR and AQUI have similar flexibility profiles, the cold adapted VPR displays higher flexibility in most regions of the protein structure. Some of these regions contain or are in proximity to some of the Trp residues (Trp6, Trp114 and Trp208) in the proteins. Thus, we observe an overall agreement between the fluorescence quenching data and the flexibility profiles obtained from the MD simulations to different flexibilities of specific regions in the proteins. 相似文献
977.
《Endocrinología y nutrición》2014,61(4):176-183
ObjectiveTranssphenoidal surgery (TSS) is the treatment of choice for Cushing's disease (CD). However, the best treatment option when hypercortisolism persists or recurs remains unknown. The aim of this study was to analyze the short and long-term outcome of repeat TSS in this situation and to search for response predictors.Patients and methodsData from 26 patients with persistent (n = 11) or recurrent (n = 15) hypercortisolism who underwent repeat surgery by a single neurosurgeon between 1982 and 2009 were retrospectively analyzed. Remission was defined as normalization of urinary free cortisol (UFC) levels, and recurrence as presence of elevated UFC levels after having achieved remission. The following potential outcome predictors were analyzed: adrenal status (persistence or recurrence) after initial TSS, tumor identification in imaging tests, degree of hypercortisolism before repeat TSS, same/different surgeon in both TSS, and time to repeat surgery.ResultsImmediate postoperative remission was achieved in 12 patients (46.2%). Five of the 10 patients with available follow-up data relapsed after surgery (median time to recurrence, 13 months). New hormone deficiencies were seen in seven patients (37%), and two patients had cerebrospinal fluid leakage. No other major complications occurred. None of the preoperative factors analyzed was predictive of surgical outcome.ConclusionsWhen compared to initial surgery, repeat TSS for CD is associated to a lower remission rate and a higher risk of recurrence and complications. Further studies are needed to define outcome predictors. 相似文献
978.
979.
Hai‐Yan Liu Huhe Chao Zhen‐Kun Liu Hong‐Fei Xia Zhihui Song Ying Yang Jing‐Pian Peng 《Journal of cellular and molecular medicine》2014,18(3):455-467
Cytochrome P450 26A1 (cyp26a1) is expressed in the mouse uterus during peri‐implantation. The repression of this protein is closely associated with a reduction in implantation sites, suggesting a specific role for cyp26a1 in pregnancy and prompting questions concerning how a metabolic enzyme can generate this distinct outcome. To explore the effective downstream targets of cyp26a1 and confirm if its role in peri‐implantation depends on its metabolic substrate RA (retinoic acid), we characterized the changes in the peripheral blood, spleen and uterine implantation sites using the cyp26a1 gene vaccine constructed before. Flow cytometry results showed a significant increase in CD4+RORγt+ Th17 cells in both the peripheral blood and spleen in the experimental group. The expression of RORγt and IL‐17 presented the Th17 cells reduction in uterus followed by the suppression of cyp26a1 expression. For greater certainty, cyp26a1 antibody blocking model and RNA interference model were constructed to determine the precise target immune cell group. High performance liquid chromatography results showed a significant increase in uterine at‐RA followed by the immunization of cyp26a1 gene vaccine. Both the ascertain by measuring RARα protein levels in peri‐implantation uterus after gene vaccine immunization and researches using the specific agonist and antagonist against RARα suggested that RARα may be the main RA receptor for signal transduction. These results provided more evidence for the signal messenger role of RA in cyp26a1 regulation from the other side. Here, we showed that the cyp26a1‐regulated Th17 cells are dependent on at‐RA signalling, which is delivered through RARα in mouse peri‐implantation. 相似文献
980.
Xiyan Zhao Xueqiang Zhu Shuting Cheng Yizhou Xie Zhengrong Wang Yanyou Liu Zhou Jiang Jing Xiao Huiling Guo Yuhui Wang 《Acta biochimica et biophysica Sinica》2014,(4):313-317
Several essential biological progresses in mammals are regulated by circadian rhythms. Though the molecular mechanisms of oscillating these circadian rhythms have been uncovered, the specific functions of the circadian genes are not very clear. It has been reported that knocking down circadian genes by microRNA is a useful strategy to explore the function of the circadian rhythms. In this study, through a forward bioinformatics screening ap- proach, we identified miR-29a/b/c as potent inhibitors for the human circadian gene hPER1. We further found that miR-29a/b/c could directly target hPER1 3/untranslated region (UTR) and down-regulate hPER1 at both mRNA and protein expression levels in human A549 cells. Thus, our findings suggested that the expression of hPER1 is regulated by miR-29a/b/c, which may also provide a new clue for the function ofhPER1. 相似文献