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排序方式: 共有899条查询结果,搜索用时 15 毫秒
1.
基于美军二战海战减员数据的校正   总被引:1,自引:0,他引:1  
程旭东  刘建  霍仲厚  陈国良  李瑞兴  秦超 《医学争鸣》2004,25(12):1150-1152
目的:通过对二战减员数据的校正,为下一步建立海战减员预计模型提供数据支持.方法:选取美军在二战太平洋海战中的减员数据作为研究的基本资料,通过专家咨询法(Delph method)对其进行校正,所有结果都对其进行了t检验.结果:水面舰艇遭受炸弹、舰炮及航空火炮、短程导弹、鱼雷和水雷的攻击时减员将减少,遭受中程导弹攻击时减员将会增加.结论:该校正结果可作为研究未来海战卫生减员预计的基本依据之一.  相似文献   
2.
利用一不依赖于实验参数的理论方法计算了钠原子Rydberg态的能级寿命,计算结果很好地符合已有的实验值及其他理论计算值,此计算方法较为严格并且可以弥补实验的不足。  相似文献   
3.
Clinical studies have demonstrated that measures of cell-mediated immune function are altered in bereaved persons and depressed patients. This review article focuses on our recent observations of changes in T cell subpopulations and natural killer cytotoxicity in women undergoing adverse life events including conjugal bereavement. A reduction in natural cytotoxicity has also been found in depressed patients. The mechanism by which psychologic states might influence immune function is discussed.  相似文献   
4.
更年期妇女生理心理健康状况探讨   总被引:26,自引:2,他引:24  
目的探讨更年期妇女生理、心理健康状况及相互关系 ,为进一步缓解更年期妇女的症状提供医疗和护理上的依据。方法对北京大学第一临床医院更年期门诊病人进行问卷调查 ,数据结果应用SPSS 8 0数据分析软件包进行处理。结果更年期妇女Kupperman总体平均分为 2 0 12± 9 97分 ,SCL 90评分量表总体平均分为 4 6 6 2±36 2 8分 ,并且以潮热出汗、失眠等躯体症状 ,以及强迫症状、人际关系敏感、抑郁、焦虑等心理症状表现突出。应用激素替代疗法后 ,能有效缓解更年期妇女潮热出汗、抑郁心烦、疲乏、骨关节痛、敌对的症状 ,与未用激素替代疗法者有显著差异。对更年期妇女的生理、心理进行分析显示 ,更年期妇女生理心理症状呈中等程度相关性 (r=0 6 17,P <0 0 0 1)。结论医护人员应加强对更年期妇女生理心理双方面的关注。  相似文献   
5.
This paper considers a pole assignment problem to cluster all poles of a closed-loop system into some specified regions by introducing the complex state for systems having an isotropic property and by using the Riccati equation. The algebraic relations for the distribution of the eigenvalues of a complex matrix are used in order to cluster the poles into specified regions, which guarantees the relative stability margin, e.g. uniform damping or uniform damping ratio. The proposed scheme is essentially a combination of the pole assignment approach and linear quadratic design, taking the advantages of both. A block modal control method—an extension of recursive pole assignment—is also developed for the vibration control of rotating systems by clustering the forward and backward modes in order. Vibration control simulations with an isotropic rotor—bearing system, a magnetic bearing system and a rotating circular disc are treated in order to demonstrate the advantages of the proposed method.  相似文献   
6.
Rats with catatonic freezing are characterized by low motor and explorative activity in the open field test and specific pattern of external respiration, so-called strenuous respiration, which is accompanied by a higher activity of the respiratory enzymes succinate dehydrogenase and NADH dehydrogenase in the hippocampus and motor cortex. No dependencies on the brain structure and animal age are noted. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 138–140, August, 1997  相似文献   
7.
This research aimed to investigate the time course of the cortical activity level preceding spontaneous awakening as a function of age and state. Two groups of infants (1-4 and 9-14 weeks of age) were continuously monitored by polygraphic recording and behavioural observation during the night. The electroencephalographic (EEG) activity recorded by the C3-O1 lead was analysed through an automatic analysis method which provides, for each 30-s epoch, a single measure, time domain based, of the EEG synchronization. The EEG parameter values were computed in the 6 min preceding each awakening out of non-rapid eye movement (NREM) sleep and out of rapid eye movement (REM) sleep. The EEG background activity level did not change in the minutes preceding awakening out of REM sleep. Awakening out of NREM sleep was preceded by a change of EEG activity level in the direction of higher activation with different time course according to the age. Both REM and NREM sleep results suggest that a high level of EEG activity is a prerequisite for the occurrence of a spontaneous awakening.  相似文献   
8.
河南省幼师学生心理健康状况调查分析   总被引:6,自引:0,他引:6  
目的 了解河南省幼师学生的心理健康状况,为提高幼师的心理素质提供依据。方法 对来自河南南阳一师,洛阳一师,郑州幼师3所学校的580名幼师女生进行症状自评量表(SCL-90)测定。数据经t检验,q检验和卡方检验。结果 幼师在校生中有63.81%学生存在心理健康问题。11.43%学生有明显心理障碍,突出表现为强迫,人际敏感,偏执,敌对,抑郁,不同年级学生心理健康状况存在明显差异。结论 提示幼师学生存在不同程度心理健康问题。学校心理卫生和教育工作者必须予以重视,进行干预。  相似文献   
9.
Urethane anesthetized (< 1 .3 g/kg), Sprague-Dawley (SD) rats spontaneously cycled between a cortically desynchronized state (State I) and a cortically synchronized state (State III), which were very similar to awake and slow wave sleep (SWS) states in unanesthetized animals, based on EEG criteria. These low levels of urethane anaesthesia did not cause significant respiratory depression or reductions in sensitivity to hypoxia (10% O2 in nitrogen) or hypercapnia (5% CO2 in air) in rats in either State I or State III. Thus, breathing frequency (fR), tidal volume (VT) and total ventilation (VTOT) all increased on cortical activation in urethane-anaesthetized rats whether breathing air, the hypoxic or the hypercapnic gas mixture, in a manner that was very similar to that observed in unanaesthetized animals. The relative sensitivity to hypoxia was greater in State III than State I, the relative sensitivity to CO2, overall, was equal in both states, State III occurred less often during hypoxia and hypercapnia, and hypoxic, urethane-anaesthetized rats sighed frequently, particularly in State I. This is also similar to the situation seen in unanesthetized rats. Given the similarities seen between urethane anesthetized rats in the present study and literature values for unanesthetized rats, the data suggest that urethane-anaesthetized rats provide a good model system for studying respiratory patterns and chemoreflexes as a function of cortical activation state.  相似文献   
10.
Salivary immunoglobulin A (IgA) is one characteristic humoral factor of the local immune system in the upper respiratory tract. Epidemiological studies emphasize the importance of secretory IgA in the protection from infections of the upper respiratory tract. However, due to high interindividual variability of secretion of salivary IgA, it remains difficult to define normal ranges. This series of studies focused on identification of factors influencing basal secretion of salivary IgA. The results indicate a significant relationship between age and salivary IgA concentration. Children below 7 years have lower salivary IgA concentration than children above 7 years or adults. Furthermore, a significant inverse relationship between saliva flow and salivary IgA concentration was found. Gender, mood states, salivary albumin, salivary catecholamines, and salivary cortisol were not associated with salivary IgA. It can be concluded that for defining normal ranges of salivary IgA, age and saliva flow have to be considered.  相似文献   
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