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Chronic fatigue syndrome: physical and cardiovascular deconditioning   总被引:2,自引:0,他引:2  
We investigated whether chronic fatigue syndrome (CFS) patients have physical and/or cardiovascular de-conditioning, in 273 CFS patients and 72 healthy controls. We used laboratory tests to assess haematological, biochemical, endocrinological and immunological systems. The cardiovascular system was assessed by echocardiography and carotid echography. Body composition was determined by dual energy X-ray absorptiometry (DEXA). CFS patients had smaller left ventricular end systolic (p < 0.001) and diastolic (p = 0.008) dimensions but thinner posterior walls (p = 0.02) than corresponding values in healthy controls. Left ventricular mass was also reduced in CFS patients (p = 0.006). Both maximum (p < 0.001) and minimum (p < 0.008) diameter of the carotid artery were smaller in CFS patients. The laboratory screening tests showed significant differences in serum albumin (p = 0.05), phosphate (p = 0.02), HDL-cholesterol (p = 0.03), HDL:total cholesterol ratio (p = 0.01), triglycerides (p = 0.02), neutrophils (p = 0.01) and thyroid-stimulating hormone (p = 0.04) between CFS patients and controls. Male CFS patients had an increased percentage of fat mass compared with healthy male subjects (p = 0.02). This large group of CFS patients had evidence of physical and cardiovascular de-conditioning, suggesting that in these patients a graded exercise programme could lead to physical reconditioning and could increase their ability to perform physical activities.   相似文献   
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A polymer system was developed for use in permanent inflation of detachable balloons, to avoid long-term reliance on the integrity of balloon shells or valve mechanisms. This system is based on 2-hydroxy-ethyl methacrylate (HEMA) as the monomer, in combination with a cross-linking agent and a water-soluble curing system. The low-viscosity, hydrophilic mixture can be exchanged through a small-bore catheter into a detachable balloon and polymerizes in 40-60 minutes at body temperature. Partially polymerized HEMA can cause vascular occlusion; hence, careful timing of balloon detachment is required. The evolution of the radiographic appearance of HEMA-filled balloons is predictable. The balloons remain radiopaque on plain radiographs as long as the balloon shell and valve mechanisms are competent. After rupture of the shell or failure of the valve mechanism, the balloons become invisible on plain radiographs but remain hyperattenuating on computed tomography scans.  相似文献   
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在进行职业训练时,对受训者的心理变化趋势进行监视是必要的。航天员心理因素的发展水平可通过心理测试来检测,以便能对其重要的心理指标进行评价,并给出综合评价。文中列出应进行测试的心理指标,并根据大量的样本统计给出了经验加权因子。测试结果的积累可以预测航天员将来飞行任务中处理复杂问题的能力,并能帮助改进训练过程及暴露缺点。  相似文献   
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俄罗斯不同气候地区不同功能水体中克雷伯菌属广泛分布。克雷伯菌属可见于遭受生物、化学污染的集中供水的地表水源,无防护的地下蓄水层,缺乏有效清洁、消毒系统的饮用水。研究表明,水体中的克雷伯菌属具有致病性和毒性,对现代药物和消毒剂(氯、紫外线)具有抗性,很容易穿透进入地下蓄水层。克雷伯菌属细菌有很强的致病性(粘附力、侵袭力、磷酸酯酶、卵磷脂酶、脱氧核糖核酸酶、溶血活性),含有致病性遗传标记cnf-1。克雷伯菌属(100 CFU/dm3)可引起急性肠道感染。在不检测总大肠菌群的情况下,检测水体尤其是饮用水中的克雷伯菌属,可以评估所用水的流行病学危险。  相似文献   
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重组腺病毒bcl-xs基因对人卵巢癌裸鼠移植瘤作用的研究   总被引:3,自引:0,他引:3  
目的 观察重组腺病毒bcl-xs基因(adv-bcl-xs基因,简称bcl-xs基因)对人卵巢癌裸鼠移植瘤的生长抑制和荷瘤裸鼠生存率的影响。为卵巢癌的基因治疗提供实验基础。方法 采用以复制缺陷型腺病毒bcl-xs基础感染的人胚肾细胞,使bcl-xs基因对NUTU-19细胞的生长抑制作用并检测其病毒滴度后,将bxl-xs基因导入人卵巢癌裸鼠移植瘤中,观察bcl-xs基因对腹水的生长抑制作用,计算裸鼠的生存时间,并观察bcl-xs基因对裸鼠全身和局部的毒副作用。电镜观察bcl-xs基因的病毒颗粒,以免疫细胞化学染色测定bcl-xs基因表达情况。结果 bcl-xs基因可在人胚肾细胞内扩增,对NUTU-19细胞有抑制和杀伤作用。并在裸鼠体内呈过度表达,使裸鼠腹水形成的时间由5-10d延长至11-23d,裸鼠平均生存时间由24d延长至39d,bcl-xs基因对裸鼠全身和局部无明显毒副作用。结论 bcl-xs基因导入人卵巢癌裸鼠移植肿瘤,能延缓腹水形成,延长裸鼠的生存时间,为卵巢癌的基因治疗提供了一种新方法。  相似文献   
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Progesterone supplementation can prevent preterm birth in some high-risk women. Progesterone binds to progesterone receptor (PR) and modulates the expression of target genes. This study investigates the association between single nucleotide polymorphisms (SNPs) in the PR gene and spontaneous preterm birth. DNA was extracted from consecutive patients with preterm birth (n = 78) and term controls (n = 415), and genotyping was performed for 3 PR SNPs (+331[G>A], + 770[C>T], +660[G>T]) using Sequenom matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Data were analyzed by chi(2) test and logistic regression analysis. Multivariate analysis showed no association between maternal carriage of minor + 331T, +770T, and/or +660T alleles and preterm birth when controlled for maternal age, ethnicity, gravidity, parity, prior preterm birth, route of delivery, or neonatal outcome. Carriage of +770T and +660T (but not +331T) was associated with preterm birth in women with a body mass index <18.5 kg/m(2) (relative risk, 10.8; 95% confidence interval, 1.4-82.6; P = .02). Maternal carriage of minor alleles of +331(G>A), +770(C>T), and +660(G> T) SNPs in the PR gene is not associated with spontaneous preterm birth.  相似文献   
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The authors describe a rare case of intracranial tuberculoma of the Meckel's cave and cavernous sinus with extension into the infratemporal fossa causing widening of the foramen ovale and adjacent bone destruction. The rarity of the lesion and the unusual extension of the lesion are presented with a brief review of literature.  相似文献   
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