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981.
BACKGROUND: Voltage-gated potassium (K+) channels may participate in cellular developmental regulation, including cell differentiation, proliferation and apoptosis. This study investigated the change of K + current densities in corneal epithelial cells during maturation and cellular senescence. METHODS: New Zealand white rabbits were divided into three age groups: newborn ( 10.0 pF. Using a whole-cell clamp technique, K+ current was recorded and current densities were calculated. Differences in K+ current densities among newborn, young and adult rabbits, as well as differences among small, medium and large cells, were analyzed. RESULTS: We delineated two types of cells manifesting different amplitudes of depolarization-activated K+ outward currents. The averaged current density of type 1 response cells was significantly larger than that of type 2 cells in newborn, young, and adult groups. For newborn epithelial cells, the depolarization-gated outward K+ current density decreased from small to medium to large cells (p = 0.049, at a membrane potential of 140 mV). A similar pattern of change in current density was also delineated for these cell sizes in young and adult rabbit corneal cells (p < 0.001 for both young and adult rabbits). An increase in depolarization-gated outward K+ current density was also delineated from newborn to young to adult rabbits (p < 0.001, p < 0.001 and p < 0.006 for small, medium and large cells, respectively, at a membrane potential of 140 mV). CONCLUSIONS: Corneal epithelial cells expressed K+ channel densities that were distinct from basal to superficial cells and from newborn to adult rabbits.  相似文献   
982.
BACKGROUND: The incidence of tuberculosis (TB) has been falling in many developed countries; however, there is a trend of an increasing proportion of TB among the elderly. The aim of this study was to evaluate the age transition of patients with TB in Taiwan from 1957 to 2001. METHODS: Data on the number of TB cases and patient age were collected from the National Tuberculosis Registry for three different 5-year periods: 1957-1961, 1977-1981, and 1997-2001. The distribution of TB cases in these three different periods was analyzed. RESULTS: The age distributions of TB patients were different among the 1957-61 (n = 26,000), 1977-81 (n = 31,363) and 1997-2001 (n = 71,447) groups. During the 1957-61 period, the most common age group was 25-44 years (50.9%). During 1977-81, the most common age group was 45-64 years (44.9%). In 1997-2001, the most common age group had shifted to people aged 65 years or older (43.7%). For the whole period from 1957 to 2001, after adjusting for age shifts in the general population, the proportion of TB patients had significantly increased in persons 65 years or older, slightly increased in persons aged 0-14 years, and decreased in the 15-24, 25-44, and 45-64-year-old age groups. For the period 1977-2001, age-specific registered case rates increased with age. CONCLUSION: The age of TB patients in Taiwan showed a rising trend from 1957 to 2001. A high index of suspicion and prompt investigation of elderly patients with signs and symptoms characteristic of TB may allow earlier diagnosis and treatment.  相似文献   
983.
Treatment of cerebral malaria with intravenous quinine is frequently associated with life-threatening cardiotoxicity. We report a case of imported cerebral malaria successfully treated with artesunate-mefloquine combination therapy. The 27-year-old woman presented with fever, sudden onset of binocular blindness and altered consciousness 10 days after a short stay in Indonesia. Hyperparasitemia with Plasmodium falciparum and P. vivax in more than 5% of red blood cells was demonstrated on peripheral blood smear. She was admitted to the intensive care unit due to shock, jaundice and acute renal failure. Because of a shortage of intravenous quinine, intravenous artesunate was given as an alternative. Her condition stabilized on the 3rd day of therapy, with resolution of fever and disappearance of parasitemia. Consolidation therapy with oral mefloquine and primaquine was then given to prevent recrudescence and relapse. The only adverse event associated with artesunate was transient reticulocytopenia, which resolved after discontinuation of therapy. Her vision completely recovered, along with renal and liver function.  相似文献   
984.
BACKGROUND/PURPOSE: Conventional training in bronchoscopy may increase patient's discomfort and procedure-related morbidity. Computer-based bronchoscopy simulator (CBBS) permits the acquisition and evaluation of the necessary skills through a realistic bronchoscopic experience. This study was conducted to validate the use of a CBBS system developed in Taiwan as a learning and assessment tool. METHODS: Twenty novice bronchoscopists and 10 expert bronchoscopists were enrolled as subjects in this prospective study. The 20 novice bronchoscopists were randomized into two groups, which received conventional bronchoscopic training or CBBS training and then completed a satisfaction survey. Subsequently, the novices who received CBBS training underwent an observational performance trial and the results were compared with those of expert bronchoscopists. All 10 expert bronchoscopists completed a realism survey and observational trial after CBBS performance. RESULTS: The satisfaction survey showed that the CBBS training program significantly increased participants' satisfaction (p = 0.002) and interest in learning (p < 0.001). The realism survey by the 10 expert bronchoscopists indicated that CBBS provides a favorable degree of realism with regard to the mechanical and visual parameters examined. Analysis of the performance results showed that the following parameters were capable of differentiating the participants by level of expertise: total procedure time (p = 0.002), percentage of bronchial segments entered (p = 0.012), percentage of bronchial segments identified (p < 0.001), percentage of repeated bronchial segments entered (p = 0.004), percentage of pathologies identified (p < 0.001), number of times that the bronchoscope tip collided with airway walls (p = 0.013), and number of times oral instruction was needed (p = 0.01). CONCLUSION: CBBS is a valid training method that increases interest in learning and provides a favorable degree of virtual realism. It can also distinguish various levels of competence at actual bronchoscopy and may have a useful role in the bronchoscopic training curriculum.  相似文献   
985.
Mycobacterium tuberculosis (TB) infection of the penis is a rare but serious problem. We report a case of penile TB in a 75-year-old man who presented with fever and dyspnea. No active lung lesions except pleural and pericardial effusion were found on chest X-ray. Monoclonal gammopathy of undetermined significance was diagnosed after serum and urine electrophoresis studies, and repeated bone marrow studies. Genital examination showed diffuse papulonecrotic skin ulcers involving the whole penile shaft, extending ventrally to the median raphe of the scrotum. Pus smear showed positive acid-fast stain, and culture yielded M. tuberculosis. Culture of pleural and pericardial effusion was also positive for M. tuberculosis. Anti-TB treatment was given with isoniazid, ethambutol, rifampin and pyrazinamide, and the cutaneous lesion was noted to be healed at follow-up 6 months later. Although rare, the possibility of TB as a cause of genital ulcer should be kept in mind.  相似文献   
986.
戴畅  马海永 《农垦医学》2006,28(5):337-339
目的:分析脊柱爆裂性骨折的螺旋CT、X线表现,并提高对螺旋CT诊断脊柱损伤价值的认识。方法:回顾性分析31例39个椎体脊柱爆裂性骨折的螺旋CT扫描和X线平片征象及临床资料,其中30例行CT多平面熏建。31倒中颈椎2例,胸椎13例,腰椎16例。结果:脊柱爆裂性骨折以T12-L2最多见(占64.1%)。X线平片主要表现为椎体高度减低,脊柱屈曲后突,椎体后缘线的改变,X线平片有14例将爆裂骨折误诊为单纯压缩型骨折。螺旋CT可清楚显示脊柱骨折范围、椎管变形狭窄程度并判断脊髓损伤。X线平片和螺旋CT对爆裂性骨折的诊断率分别为54.8%和100%;椎管狭窄的显示率分别为22.6%和77.4%。结论:X线平片是脊柱损伤的基本检查手段,但有时爆裂性骨折较难与单纯压缩性骨折区分。螺旋CT检查明显优于X线平片,对脊柱骨折的诊断、分型及指导临床治疗有重要价值。  相似文献   
987.
目的:通过哈萨克族与汉族女性胰岛素抵抗相关因素与血压关系的对比,分析是否存在种族差异。方法:抽取哈、汉民族女性共122人,哈、汉民族皆分为健康人群组及高血压人群组,比较各民族相应人群的胰岛素抵抗相关因素,采用直线相关分析分析各民族之间胰岛素抵抗相关因素与血压之间的关系。结果:在高血压人群组,哈族女性胰岛素抵抗指数(5.3±2.0)显著高于汉族女性(4.3±1.9);在健康人群组,哈族女性胰岛素抵抗指数(4.6±1.3)显著高于汉族女性(3.5±1.2);汉族女性胰岛素抵抗指数与血压显著正相关(r=0.273,P=0.034),瘦素水平与血压显著正相关(r=0.310,P=0.015);哈族女性瘦素水平及胰岛素抵抗指数与血压不相关。结论:哈族女性胰岛素抵抗显著高于汉族女性,存在种族差异;汉族女性胰岛素抵抗指数及瘦素水平与血压显著正相关,而哈族女性胰岛素抵抗指数及瘦素水平与血压不相关,存在种族差异。  相似文献   
988.
DNA double-strand breaks (DSBs) are common le-sions that occur in cells. They are caused by exogenous sources such as ionizing radiation, and by endogenous sources such as radicals generated during metabolic processes[1]. In mammalian cells, DSBs are repaired ei-ther by the homologous recombination (HR) pathways or by the non-homologous end joining (NHEJ)[2] pathways to maintain the fidelity of human genome. The basic mechanism and factor requirements of the two pathways are different. V…  相似文献   
989.
目的探讨下肢动脉血管疾病多排螺旋CTA血管成像参数的优化,以达最佳下肢血管成像.方法搜集了46例双下肢动脉多排螺旋CTA血管成像,造影剂用量按1.5ml/kg体重、注射速率2.5ml/s为一组23例,2ml/kg体重,注射速率3ml/s为二组23例.扫描延迟时间用test Bolus,层厚3mm.数据重建用最大密度投影(MIP)和实时三维(Real time 3D)及容积显示(VR3D)等.一、二组图像分别由两位高年资医师阅片.结果第一组图像对病灶显示不如第二组图像清楚.结论CTA下肢动脉造影用对比剂2ml/kg体重,注射速率3ml/s是一种较好的下肢血管成像方法.  相似文献   
990.
常素英  何武  陈春明 《卫生研究》2006,35(6):768-771
目的利用中国食物与营养监测系统1990~2005年的数据,对中国经济快速发展时期儿童生长发育特点进行分析,确定当前主要的儿童营养问题,为制定营养改善对策提供科学依据。方法本文用WHO推荐的NCHS标准评价儿童的身高体重发育状况,用Z评分方法,比较1990~2005年中国城乡5岁以下儿童的生长发育变化。结果1990年至2005年,中国5岁以下儿童的低体重率由22.6%降低到8.6%,生长迟缓率由41.4%降至13.1%。城乡儿童的生长迟缓率的差值由1990年的32个百分点降到了2005年的10.6个百分点。但中国贫困农村儿童的低体重率和生长迟缓率分别为12.3%与17.6%。由于中国儿童身高的改善滞后于体重的改善,在1992年前后出现了“生长迟缓型肥胖”现象。1995年,儿童“生长迟缓型肥胖”率最高,达12.6%。1995年后,中国城乡儿童的身高体重发育开始均衡发展,到2005年,中国儿童的身高体重均衡性有了显著的改善。结论15年来中国5岁以下儿童生长发育状况已有很大改善,城乡差距缩小。但是贫困地区儿童的营养不良患病率仍在较高水平,虽然近几年来有了较大的改善。作者提出了在保证6个月龄以下儿童纯母乳喂养的同时,采取适合中国国情的家庭内辅助食品的营养强化等综合干预措施的建议,并强调加强6~24月龄婴幼儿的辅食添加质量以及提高2岁以上儿童的膳食质量,将是进一步有效的提高中国5岁以下儿童营养状况的关键所在。  相似文献   
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