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81.
82.
Niels Jrgensen Jrn Müller Aleksander Giwercman Jakob Visfeldt Henrik Mller Niels E. Skakkebk 《The Journal of pathology》1995,176(3):269-278
The origin of testicular germ cell tumours occurring during childhood is poorly understood. In adults, the classical seminomas and non-seminomas originate from carcinoma in situ of the testis, which can usually also be detected in seminiferous tubules adjacent to the tumours. In order to contribute with information regarding a possible association between carcinoma in situ and the childhood group of germ cell tumours, we investigated seminiferous tubules adjacent to 13 infantile yolk sac tumours, five infantile teratomas, and six adolescent germ cell tumours of various types, using morphological evaluation, immunohistochemical staining with markers for carcinoma in situ cells, and densitometric DNA measurement of the germ cells. We detected clear differences between the germ cell populations adjacent to adolescent and infantile germ cell tumours. The former were associated with both normal germ cells and carcinoma in situ cells. The presence of carcinoma in situ cells strongly suggested that the adolescent tumours arose from carcinoma in situ cells, like germ cell tumours occurring in adult men. Although we were in doubt in two cases, the infantile germ cell tumours were in general not associated with carcinoma in situ cells. The aetiology of infantile yolk sac tumours and teratomas may therefore be fundamentally different from that of adolescent and adult germ cell tumours. The origin of yolk sac tumours and teratomas remains to be elucidated. 相似文献
83.
红细胞变形性的影响因素及测量方法 总被引:5,自引:0,他引:5
红细胞的变形能力是一种重要的流变现象,是影响血液循环的主要因素,具有重要的生理学意义。红细胞的变形能力是某些疾病的重要特征。本文从内部因素、外部因素和其他因素三个方面,介绍了小同因素对红细胞变形性的影响,并比较、讨论了测量红细胞变形性的主要方法。 相似文献
84.
Effects of a second bout of maximal eccentric exercise on muscle damage and electromyographic activity 总被引:2,自引:0,他引:2
Chen TC 《European journal of applied physiology》2003,89(2):115-121
This study examined whether a second bout of maximal eccentric exercise performed 3 days after the first exercise bout would
produce further changes in muscle damage and electromyographic activity (EMG). Male students (n=26) were randomly assigned to experimental 70 (EX70; n=9), experimental 30 (EX30; n=8), and control (CON; n=9) groups. The initial exercise was 30 maximal voluntary isokinetic eccentric contractions (MAX1) on non-dominant elbow flexors
at 60° s−1 (1.05 rad s-1). The EX70 and EX30 groups performed a second bout of 70 and 30 eccentric contractions (MAX2), respectively, 3 days after
MAX1. Upper arm circumference , range of motion , strength, integrated EMG (IEMG), and mean power frequency (MPF) were measured
before, immediately after, and once a day for 9 days after MAX1. Plasma creatine kinase (CK) activity and muscle soreness
were assessed before and for 9 days after MAX1. Total work, work per contraction, IEMG, and MPF were also recorded during
MAX1 and MAX2. All indicators of muscle damage changed following MAX1 for each group (P<0.05), but no indicators of additional damage (P>0.05) were apparent after MAX2 for either the EX70 or EX30 groups. IEMG (P=0.03) and MPF (P=0.04) were lower for MAX2 compared with MAX1 for both the EX30 and EX70 groups. It is concluded that performing a second
bout of eccentric exercise with damaged muscles 3 days after the initial bout does not produce further damage or retard recovery,
even when the second bout of exercise is more strenuous. EMG findings were consistent with reduced activation of fast-twitch
motor units during the second eccentric bout. These results may be interpreted as evidence of a neural protective mechanism.
Electronic Publication 相似文献
85.
一种测量牙松动度的新方法 总被引:5,自引:0,他引:5
本文是出了一种客观确定牙松动的新方法。用瞬态碰撞激震测定牙固有振动半周期T/2和减幅系数η。以T/2为主,η为辅,度量牙齿的松动度。对依据的原理从牙周动力学模型出发进行了严密的数学推导;讨论了测试方案;介绍了牙模型测试实验;最后给出实际状态下测试的初步结果。 相似文献
86.
Carol A. E. Nickerson Gary H. McClelland Doreen M. Petersen 《Journal of behavioral medicine》1991,14(3):241-266
Previous assessments of individuals' values for various contraceptive consequences have employed one of four methodologies: free elicitation, direct ratings, multiple regression, or factor analysis. All four methodologies are flawed because they produce group rather than individual values, rely on rating scales, and fail to incorporate information regarding consequence trade-offs. Axiomatic conjoint measurement is proposed as an alternative methodology and used to determine individuals' values for a selected set of contraceptive consequences at two stages of the family-planning career.Preparation of this paper was supported in part by Grants HD-10802 and HD-14403 from the National Institute of Child Health and Human Development. Appreciation is due the Statistical Computing Facility of the University of California at Berkeley. Requests for reprints should be sent to the Publications Librarian, Center for Research on Judgment and Policy, Muenzinger Psychology Building, University of Colorado, Boulder, Colorado 80309-0344. 相似文献
87.
G. R. Francis 《Medical & biological engineering & computing》1974,12(1):105-108
An instrument using analogue integrated circuits for the separation of the systolic and diastolic levels of an arterial blood-pressure waveform is described. The use of the instrument in tracking the widely varying blood-pressure signals recorded from hypertensive dogs is shown. Details of the circuitry employed and the method of construction are given. An appendix describes the useful ‘ideal-diod’ circuit. 相似文献
88.
指骨的X线测量及其性别判别关系 总被引:1,自引:1,他引:1
目的:对指骨各指节的长度及宽度进行X线测量,为法医学及人类学提供判别率较高的性别判别式。方法:随机选择健康汉族大学生186人(男90人,女96人),进行双手后前位X线拍片,分别测量各掌骨长与中点宽,将所得数据应用SPSS软件进行统计学分析。结果:男性指骨左右示指近节宽、中指近节宽及环指近节宽侧别差异有显著性意义,女性侧别差异无显著性意义;除小指近节指骨宽外,性别差异均有显著性意义。应用Fisher法提出8个性别逐步判别式,判别率在86.0%-91.9%之间。结论:以上判别式对法医学及人类学的性别鉴定简单实用,具有较高参考价值。 相似文献
89.
目的建立现场检测工作中室内桌面照度测量不确定度评定的方法,对不确定度分量进行评定,计算出扩展不确定度值。方法根据《测量不确定度评定与表示(JJF 1059.1-2012)》和《公共场所卫生检验方法第1部分:物理因素(GB18204.1-2013)》的方法,对现场测量公共场所(候诊室)室内桌面照度值的各不确定度分量进行分析和计算,最终合成标准不确定度。结果本例用照度计法对某候诊室室内照度进行测量结果为:(225±10.74)lx,扩展不确定度为10.74 lx,其中采样高度是最大不确定度分量。结论该评定方法可用于现场检测中照度值测量的不确定度评定。 相似文献
90.
《Value in health》2021,24(9):1319-1327
ObjectivesThe Quality of Life after Brain Injury-Overall Scale (QOLIBRI-OS) is a short screening instrument for assessing disease-specific health-related quality of life (HRQoL) after traumatic brain injury. To date, no reference values are available for the QOLIBRI-OS in general populations. Thus, this study aimed to establish reference values for the QOLIBRI-OS in general population samples from Italy, The Netherlands, and the United Kingdom.MethodsData were collected using an online survey. The total sample comprised 11759 participants, consisting of 3549 Italian, 3564 Dutch, and 4646 British subjects. In this sample, 49% of the total sample did not report any health complaints, whereas 51% had at least 1 chronic health condition. Reference values were deduced for the QOLIBRI-OS for health-condition–related samples and total general population samples per country. To ensure the comparability of these values, measurement invariance was assessed using a multigroup confirmatory factor analysis. Covariates characterizing the reference values were selected with the help of regression analyses.ResultsThe confirmatory factor analysis confirmed that the QOLIBRI-OS scores measured the same traumatic brain injury–specific HRQoL construct across the 3 countries. Healthy individuals reported significantly higher HRQoL than individuals with at least 1 chronic health condition. Older age and higher education levels were significantly associated with higher HRQoL.ConclusionsBecause the reference values displayed differences in terms of age and education level across the 3 countries, we recommend using country-specific reference values stratified by sociodemographic and health status in research and clinical practice. 相似文献