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21.
Summary We investigated the capacity of 6 humans to make voluntary smooth eye movements with a horizontally stabilized foveal point target. When the target was viewed on a dark field, all subjects were able to make smooth oscillatory eye movements when they attempted to imitate their own normal pursuit of sinusoidal target movement (0.2–0.7 Hz) directly preceding the stabilization on the fovea. The frequency of the imitating eye movement was in general lower than the frequency of normal pursuit by 2–35%. While fixating a foveally stabilized point target superimposed on a large, sinusoidally moving non-stabilized background, all subjects were able to make either no eye movements, eye movements nearly in phase with or eye movements nearly in counterphase with the background movement depending on the instruction to imagine the target as head-stationary, moving in phase, or moving in counterphase with the background. The accuracy of the frequency of the smooth eye movement with the stabilized target on the moving background was higher than during imitation of pursuit on the dark field but the precision of the frequency was lower than during normal pursuit. When the background moved pseudo-randomly all subjects could voluntarily inhibit their smooth eye movements or could make smooth eye movements in phase with the background. Only 2 subjects showed a limited ability to make smooth eye movements opposite to the pseudo-random background movement. The results suggest that with predictable background movement the volition of the subject rather than the movement of the background determines the eye movements when the subject looks at the foveally stabilized target.  相似文献   
22.
Summary The effect of a selective irradiation of myelin by3H -particles was studied by light and electron microscopic methods in guinea pig spinal cord. The animals were injected with [3H]leucine shortly after birth when the rate of myelin biosynthesis is high and sacrificed 130 days later. In spinal cord the radioactivity was mainly preserved in myelin because the half life of myelin proteins is much higher than that of most other CNS protein. As a consequence the irradiation dose in the white matter was much higher than in the gray matter. In myelin internally irradiated by3H -particles within 130 days at a dose of 10 Gy no alterations could be detected either by morphological or by morphometric methods.Supported by the Deutsche Forschungsgemeinschaft  相似文献   
23.
Summary Six healthy men aged 25 to 37 walked on a treadmill at work levels of 21 and 41% of their for 25 to 30 min wearing gas protective clothing (GPC) consisting of an impermeable suit with a self-contained breathing apparatus (total weight 25 kg) or shorts (control tests, CT) in a temperate environment (t a 24.3°C ± 1.0°C, rh 30–50%). When the GPC was worn at 21 and 41% , the most prominent increases, compared with the CT, were noted in the heart rate ( ± SE, 120 ± 5 vs 76 ± 3 beats min–1 and 171 ± 5 vs 103 ± 3 beats min–1), mean skin temperature (36.1 ± 0.2 vs 31.3° C ± 0.1°C and 36.9 ± 0.3 vs 30.9°C ± 0.4°C) and sweat rate (473 ± 51 vs 70 ± 23 g m–2 h–1 and 766 ± 81 vs 135 ± 18 g m–2 h–1) indicating a high cardiovascular and thermoregulatory strain, which was not decreased by ventilating the suit with an air flow of 281 min–1 at 41% . The ventilation, oxygen consumption and production of carbon dioxide increased in relation to the extra weight of the GPC, partly dependent on the dynamic work level. It was concluded that the increase in the physiological load caused by the GPC was so high that the work-rest regimens, workers' level of physical fitness, cardiovascular health and heat tolerance should be considered whenever gas protective clothing is used.  相似文献   
24.
BackgroundMusculoskeletal traumas are on the rise in the United States; however, limited studies are available to help trauma providers assess and treat concerns beyond the physical impact. Little is understood about the psychological, social, and spiritual factors that protect patients from adverse effects after a physical trauma or their experiences with each factor afterward.ObjectiveThis systematic review was conducted to investigate and review advancements in research related to risk and resiliency factors experienced by survivors of traumatic musculoskeletal injuries. The use of biopsychosocial-spiritual (BPS–S) framework and resiliency theory guided the analysis.MethodsResearchers reviewed 1003 articles, but only seven met the search criteria. Due to the complexity and uniqueness of traumatic brain injuries, studies on that target population were excluded.ResultsOf the seven articles reviewed, three identified psychological protective factors that protect against negative health outcomes; three identified negative psychological, social, or spiritual outcomes; and none investigated social or spiritual health.ConclusionsThere are significant gaps in the literature surrounding risk and resiliency factors related to the BPS-S health of musculoskeletal injury survivors.  相似文献   
25.
PurposeAdolescents are particularly vulnerable during the COVID-19 quarantine periods and may be at risk for developing psychological distress symptoms that extend beyond a crisis, including depression. This study examined adolescents’ postquarantine depressive symptoms associated with pandemic stressors. The primary aim was to identify potential protective factors that may buffer the association between the presence of COVID-19 cases in adolescents’ communities and their postquarantine depressive symptoms.MethodsAdolescents from public schools were recruited from Zhengzhou city, Henan, China (N = 1,487, Mage=13.14 years, 50% girls). Adolescents reported the presence of confirmed or suspected COVID-19 cases in their communities, their daily activities and routines during the 2-month quarantine period, and depressive symptoms after the quarantine period.ResultsThe presence of cases in adolescents’ communities during the quarantine contributed to more depressive symptoms in adolescents after the quarantine. This association was buffered by adolescents’ spending more time on physical activities and better maintenance of daily living routines during the quarantine period. The presence of community infection was also more strongly associated with depressive symptoms in older adolescents.ConclusionsThe presence of COVID-19 cases in communities contributed to adolescents’ poorer mental health, and the association was stronger for older adolescents. Spending time on physical activities and maintaining daily living routines during the quarantine appear to be practical strategies that can be used by adolescents to mitigate the association between pandemic stressors and their diminishing mental health.  相似文献   
26.
随着核能发展不断推进,居住在核电站周围的公众数量越来越多,但是他们普遍缺乏对核辐射的基础知识,对核事故的防护行动也知之甚少。而及时、正确的防护行动可以将核电站事故对公众的健康危害降到最低。本文介绍了核电站事故后,公众的防护行动:隐蔽、体表污染去污、撤离、服用稳定性碘、食品和饮用水控制、个人防护措施、宠物照料、心理援助等,以指导公众在事故后开展正确的自救与互救,提高公众对核电站事故的应急响应能力。  相似文献   
27.
本文分析经皮球囊二尖瓣成形术治疗风湿性二尖瓣狭窄的疗效。结果表明 ,PBMV耗费少 ,住院期短。效果良好 ,值得推广应用  相似文献   
28.
乙型肝炎病毒基因重组(CHO)疫苗阻断母婴传播的研究   总被引:1,自引:0,他引:1  
目的:研究乙型肝炎病毒基因重组(CHO)疫茵对HBsAg和HBeAg双阳性母亲所生婴儿的阻断效果。方法:选70例生于母亲为HBsAg和HBsAg双阳性的婴儿,随机分为A组(31例)和B组(39例),A组为单纯疫苗组,注射3次疫苗(0、1、6月,10μg/次);B组为疫苗加乙肝免疫球蛋自(HBIG)组,注射3次疫苗(同A组),并于出生时注射半支(50IU)HBIG。全程2~6个月采血,用固相放射免疫(RIA)法检测抗-HBs、HBsAg和抗-HBc。结果:抗抗-HBs阳转率为83.87%,阻断率为83.87%,疫苗加半量乙肝免疫球蛋白(50IU)组分别为93.10%和93.59%。结论:乙肝基因重组(CHO)疫苗有良好的阻断乙肝母婴传播的效果,如果出生时加注半支HBIG效果更好。  相似文献   
29.
陈加源  付凯  谢坪 《四川医学》2000,21(3):201-202
目的观察颅内病变X-刀治疗后的CT表现,评价疗效.方法51例55个颅内病变X-刀治疗后,直接增强CT扫描.结果病灶消失11例(15个病灶),病灶缩小29例,病灶失增强6例,病灶无变化5例.结论颅内病变X-刀治疗后CT表现能直接反映治疗效果.  相似文献   
30.
为观察不同剂次破伤风类毒素(TT)的免疫效果,对我省郑州市金水区、密县、辉县和三门峡市858名育龄期妇女分别进行1.2、3剂次免疫。结果显示,经1、2、3剂次TT免疫后,抗毒素均可达到较高水平,分别为0.25IU/ml、1.003IU/ml、1.093IU/ml,保护率分别达到841%、96.5%、911%.  相似文献   
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