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11.
The effects of different types of clothing on human deep body temperature were studied with six healthy male subjects in a supine posture. Two clothing ensembles were employed for the present study: A covered the whole body area with garments except the face (1.97 clo) and B covered only the trunk and the upper half of the extremities with garments (1.53 clo). The experiment was carried out in a climatic chamber at 55% ± 5% relative humidity under cooling and warming temperatures: the temperature was changed from 22°C to 10°C (cooling) and returned to 22°C again (warming). The major findings were: rectal temperature (T
re) continued to decrease gradually in A throughout the experiment, whereas in B it increased during cooling, and returned to previous levels during warming. As a result, Tre and chest skin temperature were maintained at a higher level in B than in A. Internal tissue conductances were greater in A than in B both during cooling and during warming. Thermal comfort appeared to have been influenced more by the rate of skin temperature change than by the level of skin temperature per se. It was concluded that peripheral vasoconstriction in B induced less heat flow from core to shell, and, thus, the core temperature was maintained at a higher level in B than in A. 相似文献
12.
Metabolic pathways leading to lipid biosynthesis in four different developmental stages of Schistosoma mansoni were explored and quantified by incubation in the presence of labeled precursors in a chemically defined medium. At the schistosomulum stage and in male, female, or paired worms, glycerol and oleate incorporation into neutral lipids, mainly in the form of triacylglycerols, was greater than into phospholipids, whereas in 11-and 15-day-old worms, synthesis mainly led to phospholipids. Incorporation into phospholipids was recovered largely in phosphatidylcholine, and distribution into other phospholipids depended on the developmental stage. Incorporation of choline and ethanolamine into their respective phospholipids represented up to 15% of the parasitic phospholipid content. The formation of phosphatidylcholine by phosphatidylethanolamine methylation occurred mainly in the immature parasitic stages. Inositol incorporation was also measurable, whereas [14C]serine incorporation was low or undetectable. Addition of 1-palmitoyl-2-[14C]oleyl phosphatidylcholine revealed a very high uptake of this phospholipid by the immature stages but further metabolism was not detectable. In contrast, adult S. mansoni were completely unable to take up or absorb this exogenous phospholipid. The most striking aspect of this study was the relatively high metabolic activity in 11-day-old worms and the lower but sustained activity on day 15 and at the schistosomulum stage. By comparison, biosynthetic activity in adult S. mansoni, on which research studies have been focused until now, was very low. We also discuss the participation of lipid metabolism in the constant renewal of the membrane complex which is essential to parasitism by S. mansoni. 相似文献
13.
Peter Anderer Georg Gruber Gerhard Klösch Wolfgang Klimesch Bernd Saletu Josef Zeitlhofer 《Somnologie - Schlafforschung und Schlafmedizin》2002,6(2):54-62
Summary Memory consolidation involves a complex series of molecular, cellular and network-level processes that take place on time scales from millisecond to months. Evidence from a wide range of experimental observations supports the hypothesis that parts of these processes occur during sleep when the brain is not engaged in processing and encoding incoming information. Indeed, sleep seems to be favorable for brain plasticity. Experience-dependent cortical plasticity observed during sleep has been hypothesized to be part of the global process of memory consolidation. Thus, studying task-dependent, regionally specific reactivation of neuronal assemblies during posttraining sleep may make important contributions to elucidating the role of sleep in memory trace processing. A new methodology – low-resolution brain electromagnetic tomography (LORETA) – offers the possibility of localizing electrical activity produced by cortical neuronal generators under normal (undisturbed) sleeping conditions. The high time resolution of brain electrical data can be exploited to produce neuroimages for specific EEG spectral frequency bands (e.g. delta, theta, or spindle bands). This makes it possible to investigate, dependent on the type of memory, when – in which sleep stages (S2 sleep, SWS, REM sleep) – and where – in which cortical brain regions (primary sensory cortex, higher association cortex) – experience-dependent reactivation occurs. 相似文献
14.
探讨数值模拟不同运动强度对因废用引起的骨质疏松的影响。依据骨的功能适应性和力学调控系统理论,遵循骨重建的生理过程,建立了一个带有时间历程的描述松质骨骨质疏松过程的计算模型,用C语言编制程序。得到了不同运动负荷对因废用引起的骨质疏松(孔隙率)的影响曲线。结果表明:较大的运动强度可以减缓因废用引起的骨质疏松。这对于运动防治骨质疏松有一定的参考价值。 相似文献
15.
A Nussler S Pied J Goma L Rénia F Miltgen G E Grau D Mazier 《International immunology》1991,3(4):317-321
We examined the capacity of murine recombinant tumor necrosis factor (rmTNF) to induce an inhibitory effect at the hepatic stage on malaria induced by Plasmodium yoelii sporozoites. When injected three times, 1.0 micrograms of rmTNF was found to protect 78% of mice against a sporozoite challenge. In contrast, whatever the dose and the schedule of administration, no inhibition was observed when purified hepatocyte cultures were infected with P. yoelii. The addition of non-parenchymal hepatic cells to hepatocyte cultures restored the capacity of TNF to modulate hepatic stage development, leading to up to 44% inhibition. Antibodies to interleukin 6 reversed the anti-parasite activity in the co-culture system. 相似文献
16.
目的 分析中国不同地区中老年居民门诊服务利用现状及其影响因素。方法 基于2018年CHARLS第四次调查,将中国28个省份划分为东中西部三个地区,依据安德森模型对19 136例中老年居民门诊服务利用的影响因素采用二分类多水平Logistic回归模型进行探讨。结果 我国中老年居民慢性病患病率为44.7%,其中,西部地区慢性病患病率最高(47.3%),四周就诊率最高(18.2%); 不同地区中老年居民门诊服务利用的影响因素有所不同,东部地区,女性(男性OR=0.782,95%CI:0.675~0.905)、文化水平较高(OR=1.853,95%CI:1.197~2.869)、丧偶者(OR=1.317,95%CI:1.081~1.605)四周就诊的可能性增加; 在中部地区,参加城镇职工医保(OR=2.094,95%CI:1.123~3.903)或新农合(OR=1.952,95%CI:1.069~3.563)、轻度失能(OR=1.440,95%CI:1.099~1.885)的居民四周就诊的可能性增加; 在西部地区,女性四周就诊的可能性高于男性(OR=0.718,95%CI:0.628~0.821); 三个地区均显示自评健康状况越差、慢性病患者四周就诊的可能性更高(P<0.05)。结论 我国不同地区中老年居民门诊服务利用的影响因素有所不同,自评健康状况和慢性病是三个地区四周就诊率相同的影响因素因此,在配置门诊医疗资源时,应针对不同地区的中老年人群特点进行合理倾斜。 相似文献
17.
目的研究不同带教模式在神经内科护理教学中的应用效果。方法选取2018年6月—2019年7月期间在该院实习的62名护士为研究对象,随机均分为两组,对照组采用传统教学,观察组采用PBL教学,观察两组的教学效果。结果实施后观察组护理实习生的理论知识分数(93.72±1.13)分与对照组护理实习生的理论知识分数(85.92±2.75)分相比较高,差异有统计学意义(t=14.607,P<0.001),观察组护理实习生的实践操作分数(95.25±2.43)分与对照组护理实习生的实践操作分数(84.36±4.64)分相比较高,差异有统计学意义(t=11.576,P<0.001),护生对教学的评价教学评价差评率0.00%与对照组19.35%相比较低,差异有统计学意义(χ2=4.613,P=0.032)。结论不同带教模式应用在神经内科护理教学中效果不同,PBL教学与传统教学相比较好,能够有效地提高护理实习生的理论和实践能力,受到了护理实习生的一致认可,值得在临床中应用。 相似文献
18.
目的了解高原不同海拔地区儿童肺活量肺通气量与形态指标的相关性,以便为制定高原性疾病防控策略提供参考依据。方法于2019年1月至2020年6月采用随机抽样调查法,选择青海西宁地区(海拔2260 m,低海拔组)、青海海西地区(海拔2900 m,中海拔组)、青海玉树地区(海拔4493 m,高海拔组)7~15岁中小学生作为研究对象,检测受试儿童肺活量、肺通气量和形态指标。结果低海拔组、中海拔组、高海拔组肺活量、肺通气量和形态指标比较,差异均有统计学意义(P均<0.05)。肺活量、肺通气量与肺容积呈正比关系,与肺密度、肺径线呈反比关系(P<0.05)。研究数据的logistic回归分析显示,影响儿童肺活量和肺通气量的因素有以下3个:肺密度平均值、全肺横径、全肺容积,且以上因素差异间有统计学意义(P<0.05)。结论监测儿童形态指标,关注肺密度平均值、全肺横径、全肺容积可有效判断儿童肺功能,对防治相关高原性疾病的发生具有一定价值。 相似文献
19.
温病热瘀证的病机及分期证治探讨 总被引:3,自引:0,他引:3
温病热瘀证是指在温病发生发展过程中,既有热毒炽盛又见血行瘀滞的一类急性发热性疾病,是温病学中一个独特证型,即热邪入侵体内,煎熬阴津血液,导致血液粘稠而成瘀血。热邪和瘀血相互交织,热瘀阻于脏腑经络,引起相关脏腑的病变,最终可致热瘀气脱,正气耗竭而死亡,而热毒和血瘀是整个热瘀证病变过程中始终贯穿的基本病理因素。 相似文献
20.
目的:为了解恶性肿瘤不同疗法的治疗效果。方法:对通州市5乡镇1990-1999年诊断的所有恶性肿瘤不同疗法患者进行了生存分析。结果:539例手术治疗的恶性肿瘤生存率高于2289例未手术治疗的生存率;176例放射治疗的恶性肿瘤生存率高于2652例未放射治疗的生存率;596例化学治疗的恶性肿瘤生存率高于2232例未化学治疗的生存率,差异均有非常显著性。114例中药治疗的恶性肿瘤生存率与2714例未用中药治疗的生存率比较差异无显著性。结论:对恶性肿瘤实施正规治疗是提高恶性肿瘤患者生存率的重要措施。 相似文献