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The authors present the results of investigations performed in 28 right-handed, normally seeing persons divided into 2 groups: 15 of them were in productive age and 13 in older age. The authors compared the dynamics of the behaviour of the visual functions in dependence on the age of the subjects and the stay in the glow and sodium light. No adverse influence of the sodium light on the hand localization could be detected, instead it seems that it negatively influenced the selective reaction in older productive persons in the sense of an increased number of faults.  相似文献   
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This study presents a unique observational approach to basketball, based on the theory of psychological performance crisis in competition. The approach used takes into account the responses of a player's actions to significant social factors such as team-mates, spectators, the coach and the referees. The contribution of this approach beyond traditional observational techniques is discussed. In our investigation, a single case design was used, in which a professional basketball player was observed during 10 home and 3 away games of the regular season. The relations between the observations and the crisis concept are discussed in detail. In addition, some relevant methodological and applied aspects are presented.  相似文献   
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目的 :研究氧化低密度脂蛋白 (Ox LDL)对体外培养的Zucker大鼠肾小球系膜细胞 (GMC)核因子κB (NF κB)活性的影响以及NF κB的活性变化与大鼠鼠龄及基因型的相关性。方法 :(1)将 3月龄和 10月龄Zucker肥胖大鼠及Zucker瘦型大鼠的GMC(O3m、O10m,、L3m和L10m)进行传代培养。 (2 )采用电泳迁移率变动分析 (EMSA)和超迁移率实验 (GSA) ,检测不同浓度及不同时间相的Ox LDL对GMC中NF κB活性的影响及其亚单位p5 0和p6 5的变化。利用Westernblot检测Ox LDL刺激后NF κB的核转位。结果 :Ox LDL刺激后 ,O3m、O10m及L3m3组GMC中NF κB的活性均明显强于对照组 (P <0 .0 1) ;L10m组与对照组相比较无显著差异 (P >0 .0 5 )。随着Ox LDL浓度的增加和刺激时间的延长 ,GMC中NF κB活性也相应增强 ,5 0mg/L的Ox LDL刺激 4h时 ,NF κB的活性强度达最高峰。Ox LDL主要激活NF κB的p6 5及p5 0亚单位 ;各组NF κB的活性相比较 :O3m 组高于O10m组 ,O3m组高于L3m组及O10m组高于L10m组 (P均 <0 .0 1) ;L3m组NF κB的活性高于L10m组 (P <0 .0 5 ) .结论 :Ox LDL可诱导Zucker大鼠GMC中NF κB活化 ,且呈时间和浓度依赖性 ;活性强度与大鼠的基因型及鼠龄密切相关。Ox LDL诱导的NF κB活化在Zucker肥胖大鼠的早期肾损害中起着更为重  相似文献   
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Seven male subjects performed repeated bouts of high-intensity exercise, on a cycle ergometer, before and after 6 d of creatine supplementation (20 g Cr H2O day-1). The exercise protocol consisted of five 6-s exercise periods performed at a fixed exercise intensity, interspersed with 30-s recovery periods (Part I), followed (40 s later) by one 10 s exercise period (Part II) where the ability to maintain power output was evaluated. Muscle biopsies were taken from m. vastus lateralis at rest, and immediately after (i) the fifth 6 s exercise period in Part I and (ii) the 10 s exercise period in Part II. In addition, a series of counter movement (CMJ) and squat (SJ) jumps were performed before and after the administration period. As a result of the creatine supplementation, total muscle creatine [creatine (Cr) + phosphocreatine (PCr)] concentration at rest increased from (mean + SEM) 128.7 (4.3) to 151.5 (5.5)mmolkg_1 dry wt (P < 0.05). This was accompanied by a 1.1 (0.5) kg increase in body mass (P < 0.05). After the fifth exercise bout in Part I of the exercise protocol, PCr concentration was higher [69.7 (2.3) vs. 45.6 (7.5) mmol kg“‘ dry wt, P < 0.05], and muscle lactate was lower [26.2 (5.5) vs. 44.3 (9.9) mmol kg”1 dry wt, P < 0.05] after vs. before supplementation. In Part II, after creatine supplementation, subjects were better able to maintain power output during the 10-s exercise period (P < 0.05). There was no change in jump performance as a result of the creatine supplementation (P > 0.05). These findings show that enhanced fatigue resistance during short duration high-intensity exercise following creatine supplementation is associated with a greater availability of PCr and a lower accumulation of lactate in the muscle. The finding that jump performance was not enhanced suggests that short-term creatine feeding does not influence peak power output.  相似文献   
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The Radioisotope Centre (RC) has organized for the first time in Polish hospitals a comparison of activity measurements of 99Tcm and 131I. From the 58 Polish hospitals invited, 37 participated in the comparison. Each participant got about 4 mL of 99Tcm eluate and two 131I capsules, low- and high-activity. Sources were standardized in the RC before dispatch using a 4π ionization chamber calibrated by standard solutions. Participants used their own radionuclide calibrators. The measurement results were evaluated using the En criterion and the z′-score. From all 118 measurement results received from participants, 75 results (64%) lay within ±5% of the RC value, and 99 results (84%) lay within ±10.0%.  相似文献   
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目的探讨冠脉造影和冠脉介入治疗中心室颤动(室颤)出现的特征和处理对策。方法1994年3月至2006年5月我院完成冠脉造影及冠脉介入治疗1620例次,回顾性总结术中发生心室颤动病例,临床资料和抢救体会,并分析其原因。结果1620例冠脉介入术发生室颤7例(0.4%),6例除颤后转为窦性心律,1例抢救失败。室颤均发生于多支血管病变,发生室颤前均有冠状动脉压力下降。结论室颤易发生于多支血管病变的患者,术中应密切监测压力及心电图变化,及早实施电除颤是抢救成功的关键。  相似文献   
10.
An increased incidence of monkeypox (MPX) infections in the Democratic Republic of the Congo was noted by the regional surveillance system in October 2013. Little information exists regarding how MPX is introduced into the community and the factors associated with transmission within the household. Sixty-eight wild animals were collected and tested for Orthopoxvirus. Two of three rope squirrels (Funisciurus sp.) were positive for antibodies to Orthopoxviruses; however, no increased risk was associated with the consumption or preparation of rope squirrels. A retrospective cohort investigation and a case–control investigation were performed to identify risk factors affecting the introduction of monkeypox virus (MPXV) into the community and transmission within the home. School-age males were the individuals most frequently identified as the first person infected in the household and were the group most frequently affected overall. Risk factors of acquiring MPXV in a household included sleeping in the same room or bed, or using the same plate or cup as the primary case. There was no significant risk associated with eating or processing of wild animals. Activities associated with an increased risk of MPXV transmission all have potential for virus exposure to the mucosa.  相似文献   
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