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51.
Summary Maximal oxygen uptake was assessed in 101 randomly selected 8 and 13 year old children. In both age groups a significantly higher aerobic capacity was found in boys than in girls, both in absolute terms and when maximal oxygen uptake was related to body weight, lean body mass and lean leg volume. Among girls, maximal oxygen uptake per kg body weight was lower in the older than in the younger (p<0.05). Estimation of spontaneous physical activity, by means of a questionnaire and the actometry method, indicated that physical activity was greater in children with a high than in those with a low aerobic capacity.  相似文献   
52.
目的 :了解慢性老年精神分裂症患者认知功能和日常生活能力状况 ,探讨此类患者在额叶执行功能和记忆方面的神经心理功能障碍及其特征。方法 :采用简易智力状态检查 (MMSE)、日常生活能力量表 (ADL)、威斯康星卡片分类测验 (WCST)及韦氏记忆量表 (WMS)对 31例慢性老年精神分裂症和 31例正常对照组进行比较研究。结果 :慢性老年精神分裂症组MMSE得分明显低于正常对照组 (P <0 .0 1) ;而该组ADL总分明显高于正常对照组(P <0 .0 5 )。除非持续错误外 ,慢性老年精神分裂症患者的威斯康星卡片分类测验和韦氏记忆量表的各项测验成绩均差于对照组 (P <0 .0 5 )。结论 :慢性老年精神分裂症患者认知功能的障碍决定了患者日常生活能力的减退 ;这类患者有明显的额叶执行功能障碍和记忆障碍  相似文献   
53.
Several types of neurons were differentiated on the basis of a study of neuronal activity in various parts of the cortex near the sulcus principalis during the execution of spatial delayed reactions by monkeys. It was established that the different types of neurons are represented in different numbers in. different parts of the cortex near the sulcus principalis. The determination of several factors influencing the activity of these neurons and the comparison of data on their quantitative representation in the anterior, middle, and posterior parts of the cortex near the sulcus principalis with the existing behavioral data obtained after local ablations of identical regions of the brain made it possible to postulate that neurons belonging to the different types are involved in the analysis of different processes and represent different functional units.Translated from Fiziologicheskii. Zhurnal SSSR imeni I. M. Sechenova, Vol. 71, No. 12, pp. 1488–1494, December, 1985.  相似文献   
54.
Rising youth obesity is a serious public health concern. There is a widespread view that declining physical activity is contributing to this trend. A total of 929 young South Australians (age = 9–15 years) were surveyed in 1985 and 2004 on usual physical activity in several contexts, including attitudes to physical activity. Eight of 10 South Australian schools participating in the 1985 Schools Health and Fitness Survey were revisited in 2004. Comparisons were made on: organised sport, active transport, physical education (PE), playground activity, vigorous physical activity (VPA), total leisure-time physical activity (LTPA), and attitudes to PE and school sport. The questionnaire and method of administration were identical in both surveys. There were no differences between surveys in club and school sport participation, walking to school, and reported enjoyment of PE and school sport. In 2004 fewer children rode to school, but PE classes were more frequent. The percentage of children who ‘sit and talk’ during school breaks had increased, with a decreased percentage of older girls who ‘run around’ during school breaks. There was a significantly higher LTPA in MET.min in 2004 for boys, which was particularly evident at higher percentiles. There were no changes in mean or distribution of LTPA for the whole sample or girls. The percentage of respondents reporting ≥3 bouts of VPA in the previous week rose from 51% (1985) to 76% (2004). There is no consistent evidence of declining physical activity among South Australian youth. It is apparent that physical activity in some contexts has declined, while in other contexts levels are the same or higher than in 1985. This underscores the complex nature of physical activity and the influences on this behaviour.  相似文献   
55.
Serum levels of Epinephrine (E), norepinephrine (NE), heart rate (HR), skin conductance reaction (SCR) and skin conductance level (SCL) were measured in schizophrenic, endogenous depressed and anxiety patients as well as in normal controls. Conditions were rest, noise and a mental arithmetic (MA) task. Schizophrenic and depressed patients had an attenuated HR response to MA. Moreover, Schizophrenic patients also had higher NE base level and the highest NE secretion during noise. Anxiety and depressed patients showed significantly lower phasic electrodermal activity (SCR) throughout the whole trial, exclusively anxiety patients had significantly higher tonic electrodermal activity (SCL). These findings indicate that autonomous reactions discriminate between patient groups and controls as well as between each other.  相似文献   
56.
The aim of this study was to assess risk behaviors and its association with caries activity and dental caries in Japanese children. The subjects were 392 young Japanese children who underwent dental health check-up at 18, 30 and 42 months of age. Oral examinations, Cariostat tests and dental health questionnaires were carried out at each time. The caries prevalence of children was 1.5% at 18 months, 9.9% at 30 months and 28.1% at 42 months. Caries activity based on the Cariostat scores of children was correlated with caries status (caries-free/carious) at 42 months. In children with caries during each examination period at 42 months, eating snacks while playing was ranked as the most important behavioral risk (P < 0.001), followed by breast-feeding (P < 0.01), non setting of time for snacks (P < 0.05) and frequency of snacks (P < 0.05) at 18 months old; non brushing by mother (P < 0.05) and eating snacks while playing (P < 0.05) were ranked highest at 30 months old. In addition, eating snacks while playing (P < 0.001) at 42 months old was the only a significant factor for children with caries. Caries activity and risk behaviors were associated with caries experience at different age periods of childhood.  相似文献   
57.
Some novel N(1)-arylidene-N(2)-cis-2,6-diphenyltetrahydrothiopyran-4-one azine derivatives were synthesised and their antibacterial activity against Streptococcus faecalis, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and antifungal activity against Candida-6, Candida-51, Aspergillus niger, and Aspergillus flavus were evaluated.  相似文献   
58.
目的 检测非甲-非庚型肝炎患者肝组织输血传播病毒(TTV)感染状况,TTV感染与肝组织炎症程度 及与血液学指标的相关性。方法 应用免疫组织化学法检测52例非甲-非庚型肝炎患者肝组织中TTV,并经原位 杂交证实;对TTV阳性和阴性组的血液学生化指标,诸如血清丙氨酸转氨酶(ALT)、血清天冬氨酸转氨酶(AST)、血 清总胆红素(TBIL)、白蛋白(ALB)、γ 球蛋白(γ G)、凝血酶原活动度(PTA)及组织学活动指数(HAI)进行了比较。 结果 非甲-非庚型肝炎患者肝组织中TTV抗原(TTVAg)阳性15例,检出率为28.8%;阳性物质主要定位于肝细 胞浆内,呈棕黄色细小颗粒,偶见肝细胞核内有表达;TTV阳性表达细胞呈单个、散在或片簇状分布;TTVAg阳性的 组织切片经苏木素-伊红(HE)染色后,可观察到病毒性肝炎的一些病理变化,如肝细胞胞浆疏松化、气球样变、嗜酸 样变、灶性坏死、凋亡、小叶内及汇管区炎细胞浸润;从15例TTVAg阳性病例中任选10例进行TTV DNA原位杂交 检测,结果8例阳性,二者符合率80.0%;同时对5例免疫组化TTVAg阴性肝组织进行TTV DNA原位杂交检测,结 果5例均为阴性,二者符合率100%;TTVAg阳性组ALT、AST、TBIL、γ G均值均高于TTVAg阴性组,ALB、PTA 均值均低于TTVAg阴性组,但两组比较差异无统计学意义(P>0.0  相似文献   
59.
研究了高压脉冲电场(PEF)对乳铁蛋白(LF)的抑菌性能的影响。结果表明,LF质量浓度、电场强度、脉冲频率、脉冲数的增加,有利于LF抑菌能力的增强,而温度的升高会使之减弱。电场强度为35 kV/cm时,LF的抑菌能力达到最大值。LF的质量浓度越高,对电场强度的变化越敏感。当脉冲个数达到744时,LF的相对抑菌能力提高了34%。处理温度为15~55℃时,PEF处理的LF的相对抑菌性能增长了5%左右。当温度升高至65℃时,LF的相对抑菌能力下降显著,降低了约22%。  相似文献   
60.
目的:初步分析人源性多肽pCM-19的抗菌作用机制。方法:利用荧光素掺入破损细胞膜的原理,采用流式荧光激活细胞分析(FACScan)和扫描电子显微镜分析pCM-19对靶菌膜的作用机制。结果:FACS分析法结果显示pCM-19处理后的大肠杆菌PI着染细菌比例明显高于未处理组,并且随作用时间的延长,PI着染BL-21菌比例增大,20min时达最高水平,20min以后反而降低;扫描电子显微镜观察到pCM-19处理后的大肠杆菌有明显的表面形态学的改变,如细菌体积缩小、细菌表面出现皱缩、凹陷似有孔洞形成。结论:人源性多肽pCM-19可能作用于细菌细胞壁和(或)细胞膜,通过改变其通透性而发挥杀菌作用。  相似文献   
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