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81.
论述了医疗保障制度改革给医院带来的机遇与挑战,认为医院应采取调整结构,转换运行机制;完善补偿机制;加大宏观调控力度,制订和实施区域卫生规划等配套措施,来适应医疗保障制度的改革。 相似文献
82.
Currently used nucleic acid amplification tests for the detection of viruses and atypicals in acute respiratory infections 总被引:1,自引:0,他引:1
For the detection of respiratory viruses conventional culture techniques are still considered as the gold standard. However, results are mostly available too late to have an impact on patient management. The latest developments include appropriate DNA- and RNA-based amplification techniques (both NASBA and PCR) for the detection of an extended number of agents responsible for LRTI. Real time amplification, the latest technical progress, produces, within a considerable shorter time, results with a lower risk of false positives. As results can be obtained within the same day, patient management with appropriate therapy or reduction of unnecessary antibiotic therapy in LRTI will be possible. A number of technical aspects of these amplification assays, and their advantages are discussed.The availability and use of these new diagnostic tools in virology has contributed to a better understanding of the role of respiratory viruses in LRTI. The increasing importance of the viral agents, Mycoplasma pneumoniae and Chlamydophila pneumoniae in ARI is illustrated. A great proportion of ARI are caused by viruses, but their relative importance depends on the spectrum of agents covered by the diagnostic techniques and on the populations studied, the geographical location and the season. The discovery of new viruses is ongoing; examples are the hMPV and the increasing number of coronaviruses. Indications for the use of these rapid techniques in different clinical situations are discussed. Depending on the possibilities, the laboratory could optimize its diagnostic strategy by applying a combination of immunofluorescence for the detection of RSV an IFL, and a combination of real-time amplification tests for other respiratory viruses and the atypical agents. When implementing a strategy, a compromise between sensitivity, clinical utility, turn around time and cost will have to be found. 相似文献
83.
M. Parczewski J. Kordek E. Janczewska A. Pisula W. Łojewski Ł. Socha M. Wawrzynowicz-Syczewska M. Bociąga-Jasik A. Szymczak I. Cielniak E. Siwak E. Mularska B. Aksak-Wąs A. Urbańska N. Lübke 《Clinical microbiology and infection》2019,21(4):513.e1-513.e6
Objectives
The aim of the study was to characterize the differences in the frequencies of NS3 and NS5A resistance-associated variants (RAVs) among Polish therapy-naive genotype 1 (G1) hepatitis C virus (HCV)-monoinfected and human immunodeficiency virus (HIV)/HCV-coinfected patients including clustering patterns and association of RAV frequency with liver fibrosis.Methods
NS3/NS5A RAVs were identified by population sequencing in 387 directly acting antiviral treatment-naive G1-infected individuals (54 with genotype 1a (G1a) and 333 with genotype 1b (G1b)). Liver fibrosis was assessed based on histopathology or ultrasound elastography. Phylogenetic clusters were identified using maximum likelihood models. For statistics, chi-squared or two-sided Fisher's exact tests and multivariate logistic regression models were used, as appropriate.Results
NS3 RAVs were found in 33.33% (18/54) for G1a and 2.62% (8/297) for G1b whereas NS5A variants were present in 5.55% (3/54) G1a and 9.31% (31/333) G1b sequences. Variations in NS5A 31 and 93 codon positions were found only in G1b (4.2% (14/333) for L31I/F/M and 5.39% (17/333) for Y93H). NS5A RAVs were more frequent among patients with advanced liver fibrosis (17.17% (17/99) for F3–F4 versus 6.94% (17/245) for F0–F2; p 0.004) or liver cirrhosis (20.34% (12/59) for F4 versus 7.72% (22/285) for F0–F3; p 0.003). Liver cirrhosis (F4) was associated with higher odds ratio of the NS5A RAVs among HCV-infected patients (odds ratio 2.34, 95% CI 1.004–5.291; p 0.049). NS5A RAVs were less frequent among sequences forming clusters and pairs (5.16% (8/155) versus 11.21% (26/232); p 0.039).Conclusions
Presence of NS5A RAVs correlated with progression of liver fibrosis and represents de novo selection of variants rather than transmission of drug resistance. Hence, the presence of NS5A RAVs may be a predictor for a long-lasting HCV infection. 相似文献84.
Although gross insertions (>20 bp) comprise <1% of disease-causing mutations, they nevertheless represent an important category of pathological lesion. In an attempt to study these insertions in a systematic way, 158 gross insertions ranging in size between 21 bp and approximately 10 kb were identified using the Human Gene Mutation Database (www.hgmd.org). A careful meta-analytical study revealed extensive diversity in terms of the nature of the inserted DNA sequence and has provided new insights into the underlying mutational mechanisms. Some 70% of gross insertions were found to represent sequence duplications of different types (tandem, partial tandem, or complex). Although most of the tandem duplications were explicable by simple replication slippage, the three complex duplications appear to result from multiple slippage events. Some 11% of gross insertions were attributable to nonpolyglutamine repeat expansions (including octapeptide repeat expansions in the prion protein gene [PRNP] and polyalanine tract expansions) and evidence is presented to support the contention that these mutations are also caused by replication slippage rather than by unequal crossing over. Some 17% of gross insertions, all >or=276 bp in length, were found to be due to LINE-1 (L1) retrotransposition involving different types of element (L1 trans-driven Alu, L1 direct, and L1 trans-driven SVA). A second example of pathological mitochondrial-nuclear sequence transfer was identified in the USH1C gene but appears to arise via a novel mechanism, trans-replication slippage. Finally, evidence for another novel mechanism of human genetic disease, involving the possible capture of DNA oligonucleotides, is presented in the context of a 26-bp insertion into the ERCC6 gene. 相似文献
85.
在过去10年中,随着功能脑影像学技术在物质滥用领域的发展,越来越多的研究者运用这些技术以探讨尼古丁成瘾的神经生物学机制。本文主要总结了尼古丁急、慢性暴露下对脑功能影响的神经脑影像学研究进展,证实了尼古丁依赖与中脑边缘犒赏系统、调节注意、记忆、运动以及联想相关脑环路之间的相关性。这些研究发现将为揭示尼古丁依赖的神经生物学机制提供更多的证据支持,进一步促进今后戒烟治疗的发展。 相似文献
86.
物质成瘾Stroop任务是考察物质成瘾者对成瘾相关刺激产生注意偏向的一种研究范式。研究者们采用多种实验任务和研究方法,对物质成瘾Stroop干扰产生的心理机制进行了考察,并提出了几种理论解释,但目前这些理论解释之间还存在一定的分歧。最后,本文提出了未来研究的一些建议。 相似文献
87.
原发性肝癌患者抑郁症状与不成熟防御机制的关系 总被引:7,自引:0,他引:7
目的:了解原发性肝癌(PLC)患者的抑郁症状和不成熟防御机制(IDM)的水平,探讨PLC患者的抑郁症状与IDM的关系。方法:采用流调用抑郁自评量表(CES-D)和防御式方式问卷(DSQ)对PLC患者和健康组各100例进行调查。结果:1)PLC患者中49%可能或肯定有抑郁症状,其中23%肯定有抑郁症状,其发生率高于健康组;2)PLC组的CES-D总分高于健康组;3)PLC组比健康组采用较多分裂和潜意显现机制,采用较少抱怨机制;4)肯定有抑郁症状者比无抑郁症状者采用较多IDM;5)两组CES-D总分与IDM均分呈显著正相关,Pearson r为0.473-0.776,其中PLC组为0.473。结论:抑郁症状是PLC患者常见的负性情绪,医护人员应引起重视,并指导患者采用成熟的防御机制代替不成熟防御机制,预防并减轻患者的抑郁症状,以提高患者的生活质量。 相似文献
88.
电磁脉冲辐射对猕猴凝血机制影响研究 总被引:2,自引:0,他引:2
目的:探讨电磁脉冲对猕猴凝血机制影响。方法:经高场强电磁脉冲源以6×104V/m全身辐照5只猕猴,于照前及照后1、3、7、14、28及90d下肢前静脉采血,采用AYW-8001型血凝仪检测电磁脉冲对动物血浆中TT、PT、APTT及FIB的影响。结果:动物血浆中TT于伤后1d及14~28d延长,APTT于伤后1d延长,FIB含量于伤后14d减少,PT在照射前后无明显变化。结论:电磁脉冲照射可对实验猕猴凝血机制产生影响,可通过TT、APTT延长和FIB含量减少而使机体凝血机制发生障碍。 相似文献
89.
目的探讨躯体形式障碍的治疗方法。方法用钟友彬的认识领悟疗法对躯体形式障碍3案例治疗通程予以报告和分析。结果认识领悟疗法对躯体形式障碍有一定的临床治疗效果。结论认识领悟疗法治疗躯体形式障碍是有效的和可行的。 相似文献