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排序方式: 共有826条查询结果,搜索用时 31 毫秒
1.
目的 :研究贫血病人 SF、STf R和 FEP间的关系。方法 :测定 116例贫血病人血清中 SF、STf R和 FEP。结果 :如果以 SF<15μg/ L为界值 ,STf R和 FEP诊断 IDA的敏感度分别是 79%和 81% ,如果以 SF>2 0 0μg/ L为界值 ,STf R和 FEP诊断 IDA的特异性分别为 76 %和 5 9% ;SF<15μg/ L时 ,FEP和 STf R之间有良好的相关性 (r=0 .89,P<0 .0 0 1) ,FEP和 MCV及 STf R和 MCV之间均呈负相关 (r=- 0 .75 ,P<0 .0 0 1及 r=- 0 .72 ,P<0 .0 0 1)。结论 :对单纯 IDA病人 ,如果 SF<15 μg/ L,FEP和 STf R诊断 IDA是相当的 相似文献
2.
A long-latency response component (N1m) and the sustained field (SF) of the auditory evoked magnetic field elicited by two composite stimuli (a two-tone combination and a two-formant vowel) and their individually presented components (a 600-Hz and a 2100-Hz pure tone and two single-vowel formants with formant frequencies matched to the tone frequencies) were recorded using a 37-channel magnetometer. The response to the composite stimuli differed from the linear sum of the responses to the respective components in latency, equivalent dipole moment, and equivalent dipole location, suggesting an interaction among the processes elicited by the constituents of composite stimuli. Nlm and SF source locations were more medial for the response to the high tone than to the low tone and more medial for the response to the high vowel formant than to the low vowel formant. The Nlm formant sources were more lateral than the Nlm tone sources. These findings suggest that, at the level of the auditory cortex, vowels are represented in terms of both the spectral pitches determined by their most prominent harmonics and, within the latency range of the Nlm, the virtual pitch determined by the spacing of the harmonics. 相似文献
3.
[目的]探讨不同起搏模式对病人生存质量(QOL)的影响。[方法]以健康调查问卷(SF一36量表)对112例不同起搏模式病人进行问卷调查,比较3种起搏模式下病人的QOL水平。[结果]除机体疼痛、角色情绪2个维度外其余6个维度(生理功能、角色限制、活力、社会功能、精神健康、总体健康)3种起搏模式间比较差异有统计学意义(P〈0.05)。[结论]应用AAI型、DDD型起搏器的病人生存质量优于VVI型起搏。 相似文献
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The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain. 相似文献
6.
Buckner C Gines LG Saunders CJ Vojtech L Srivastava I Gettie A Bohm R Blanchard J Barnett SW Safrit JT Stamatatos L 《Virology》2004,320(1):167-180
The potential of vaccine-elicited anti-HIV envelope antibodies to control HIV-infection was evaluated by immunizing macaques with the HIV envelope protein and transiently depleting them of their CD8+ cells before intravenous challenge with the pathogenic CCR5-tropic SIV/HIV chimeric virus, SHIV(SF162P4). Although sterilizing immunity was not achieved, all vaccinated animals effectively controlled infection and remained free of disease for the duration of observation (over 3 years). In contrast, during the same period, the control animals progressed to disease. Both the vaccinees and the controls developed robust cell-mediated antiviral and neutralizing antibody responses following infection. A comparative analysis of these responses suggests that the more effective long-term control of infection by the vaccinated animals is due to the more rapid development of anti-HIV envelope antibodies. These studies suggest that priming by vaccination of B cell anti-HIV envelope responses maybe crucial for the long-term control of HIV infection. 相似文献
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目的:探讨SF-36量表用于农村居民健康状况测定的可能性。方法:用中文版SF-36量表测定富阳2-7名14岁以上的农村居民,分析其信度,效度。结果:除了SF,RE维度,其余6维度内部一致性信度系数大于0.50,7维度内部一致性信度大于与其他维度的相关,因子分析产生3个主成分,累计方差贡献为64.6%,65岁以上者无应答,青年组与中年组各维度平均分数差异不显著,不同性别只在RP维度上判别显著,吸烟者与不吸烟者,饮酒者与不饮酒者的得分差异不显著,不同文化程度人群的得分差异不显著。结论:尚需更多证据支持SF-36量表适用于农村居民健康状况测定。 相似文献
9.
四川省城乡居民SF-36评价参考值 总被引:8,自引:0,他引:8
目的 制定 36条目简明量表 ( SF- 36 )参考值用于国内生命质量评价。方法 采用美国的评分标准及中国评分标准分别对四川省 16 0 3名农村居民和 6 46名城市居民的生命质量进行评价 ,并与香港及美国常模比较。结果 中国评分标准与美国评分标准所得结果高度相关 ,8个领域的相关系数均在 0 .98以上 ,但两种评分标准所得结果的差异有显著性 ;四川省城乡居民 SF- 36评价结果与香港及美国常模比较 ,更接近香港评价值 ;不同年龄、性别及城乡人群之间的评分结果有显著性差异。结论 制定了四川省城乡不同性别及年龄居民的 SF- 36评价参考值 ,为在国内使用 SF- 36作为生命质量评价工具奠定了基础 相似文献
10.
This paper investigates the role of biased health perceptions as a potential driving force of risky health behaviors. We define absolute and relative health perception biases, illustrate their measurement in surveys and provide evidence on their relevance. Next, we decompose the theoretical effect into its extensive and intensive margin: When the extensive margin dominates, people (wrongly) believe they are healthy enough to “afford” unhealthy behavior. Finally, using three population surveys, we provide robust empirical evidence that respondents who overestimate their health are less likely to exercise and sleep enough, but more likely to eat unhealthily and drink alcohol daily. 相似文献