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The association between breastfeeding and diarrhoeal morbidity was examined in a prevalence study of 5502 children aged 6-71 months from rural and urban Bangladesh. Breastfeeding was found to be associated with reduced prevalence of diarrhoea. This association was most pronounced at the age of six months and declined linearly to zero at approximately 30 months of age; thereafter, breastfeeding was increasingly associated with diarrhoeal illness. The linear association was found only among those children who have no access to modern health services and information, when controlling for urban and rural differences. The literature provides two opposing explanations for the positive association of prolonged breastfeeding with diarrhoeal illness. The first explanation suggests that breastfeeding can be seen as mothers' response to children's poor health. The second explanation incriminates sub-optimal child feeding practices, characterised by prolonged breastfeeding and inadequate quality and quantity of complementary foods, as the cause of malnutrition and diarrhoea. Further studies are needed to identify which explanation is correct, given the public health implications in terms of children's survival, growth and development.  相似文献   
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OBJECTIVE: The association between cancer and venous thrombosis is well established, however, that between malignancy and arterial thrombosis is less well described. Isolated cases have been reported and chemotherapy has been implicated as a cause though its significance compared with the malignant disease process itself is not known. This study examines the outcome of patients with malignant disease who present with arterial thrombosis. METHOD: Details of patients with malignant disease who presented with arterial thrombosis were analysed. RESULTS: Twenty patients presented with malignancy and arterial thrombosis, 16 presented in the last four years. The most common malignancy was metastatic breast cancer. Thrombosis involved the leg in 19 cases and the arm in one. Four patients also had venous thromboembolic events and one had a carotid artery thrombosis. Eight patients underwent operative treatment for their thrombosis. Five out of six thromboembolectomies and two out of three bypass procedures failed. Twelve had conservative or palliative treatment. Outcome was generally poor, two patients had major amputations and seventeen died at median follow-up of eight weeks. Survival rate from the time of presentation of arterial thrombosis was 50% at three months and 17% at one year. CONCLUSION: Patients with critical limb ischaemia due to atherosclerotic disease have an expected survival of approximately 80% at one year. The outcome of patients with arterial thrombosis associated with malignant disease is far worse. Arterial thrombosis is an agonal event in many of these patients. Conservative or palliative treatment may be the most appropriate management.  相似文献   
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BACKGROUND: Although upper gastrointestinal endoscopy is generally a safe procedure, it is known to be associated with arterial oxygen desaturation, resulting in rare serious cardio-pulmonary events. OBJECTIVE: To determine the severity of oxygen desaturation during nonsedated upper gastrointestinal endoscopy and study the effect of various variables on oxygen saturation. METHODS: 126 patients underwent nonsedated upper gastrointestinal endoscopy (82 diagnostic, 44 therapeutic). Arterial oxygen saturation (SaO2) was monitored using a pulse oximeter. RESULTS: Baseline SaO2 was mean (SD) 97.8 (1.8%). It remained > 95% in 60.2% of patients during the procedure, whereas mild oxygen desaturation (SaO2 90%-94%) occurred in 23.7% and severe oxygen desaturation (SaO2 < 90%) occurred in 15.8% of patients. Six patients (4.7%) required supplemental oxygen administration sometime during the procedure. Desaturation occurred in patients undergoing diagnostic and therapeutic procedures but was severe in the latter group (p < 0.002). Patients aged more than 60 years (p < 0.001), hemoglobin < 10 g/dL (p < 0.001), history of smoking (p < 0.001), and underlying chronic obstructive airway disease (p < 0.001) were significantly related to oxygen desaturation. However, on multivariate analysis, no significant correlation was observed with hemoglobin value. CONCLUSION: Therapeutic intervention during nonsedated upper gastrointestinal endoscopy, old age, smokers and chronic obstructive airways disease are independent risk factors for oxygen desaturation. We recommend continuous monitoring of SaO2 in these high-risk patients undergoing upper gastrointestinal endoscopy.  相似文献   
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目的:分析肾移植术后常见并发症肾功能延迟恢复的诱因,并观察术后血液净化干预所发挥的临床效应。方法:选择1996—12/2006—12在解放军第三军医大学大坪医院野战外科研究所泌尿外科明确诊断为肾移植术后肾功能延迟恢复的患者193例,其中接受尸肾移植192例,活体肾移植1例,均知情同意。根据患者的临床资料,分析术后肾功能延迟恢复的主要原因。除5例因术前安置腹膜透析管继续采用腹膜透析外,其余均选择血液透析治疗,其中35例穿插接受过连续性肾脏替代治疗或血液透析滤过,8例血浆置换2-5次。终止透析的标准为每日尿量〉1500mL,血肌酐〈300μmol/L。分析术后肾功能延迟恢复的原因,观察接受透析治疗后肾功能延迟恢复患者的临床疗效。结果:193例患者全部进入结果分析。①术后肾功能延迟恢复的病因:急性肾小管坏死89例(46.1%),术后早期低血压42例(21.8%),排斥反应37例(19.2%),动静脉吻合口狭窄9例(4-7%),尿路梗阻8例(4.1%),动脉过长扭曲5例(2.6%),环孢素A肾毒性2例(1.0%),髂内动脉粥样硬化斑块阻塞1例(0.5%)。(④术后肾功能转归:移植肾功能恢复正常者145例(75.1%);术后3个月血肌酐135-300μmol/L29例(15.3%);〉300μmol/L15例(7.8%);因超急性排斥反应切除移植肾2例(1%),肺部重症感染死亡2例(1%)。③术后接受血液透析次数:术后接受血液透析189例,透析1—5次移植肾功能恢复正常20例(13.8%);6-10次41例(28.3%);11-20次82例(56.6%);21-25次2例(1.4%);〉25次44例,仅1例恢复正常(0.7%),其余43例患者带肾存活。结论:急性肾小管坏死、术后早期低血压和排斥反应是引起肾移植术后肾功能延迟恢复的主要原因。在肾功能延迟恢复患者确定以血液净化为主的方案后,绝大多数移植肾功能可以恢复。  相似文献   
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目的:慢性移植肾失功是导致后期移植肾丧失的重要原因之一,文章拟探讨慢性移植肾失功的相关因素及防治措施。方法:①选择1993-12/2006-12于解放军第三军医大学大坪医院行肾移植术后发生慢性移植肾失功患者356例,回顾性分析其临床资料。②调整免疫抑制剂方案,停服硫唑嘌呤、环孢素A或减少环孢素A30% ̄50%剂量,改用他克莫司0.5 ̄1mg/(kg·d)、霉酚酸酯1 ̄2g/d、西罗莫司1 ̄2mL/d等药;控制血糖、血脂、血压,抗凝及补充鱼肝油丸;服用雷公藤、百令胶囊或尿毒清等中药,给予低蛋白、低磷及高维生素、氨基酸饮食;必要时手术切除移植肾。③分析肾移植术后发生慢性移植肾失功的危险因素并观察其治疗结果。结果:①慢性移植肾失功的危险因素:急性排斥反应254例(71.35%),巨细胞病毒感染65例(18.26%),移植肾肾小球肾炎21例(5.9%),药物中毒(环孢素A/他克莫司)9例(2.53%),高血压/高血脂/高血糖5例(1.41%),肾单位减少(高龄供肾/性别差异)2例(0.56%)。②治疗结果:切除移植肾194例(54.49%),带肾存活、恢复血液透析87例(24.44%),经治疗血肌酐维持在200 ̄300μmol/L63例(17.70%),死亡12例(3.37%)。结论:急性排斥反应是引起肾移植术后慢性移植肾失功的主要因素。提高供肾质量,严格组织配型,减少移植肾功能延迟恢复的发生,制定个体化免疫方案,定期监测药物浓度及肝肾功能,预防巨细胞病毒感染,可减少慢性移植肾失功的发生。  相似文献   
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