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The etiology of acute myeloid leukemia (AML) is relatively unknown. Incidence rates are highest in the agricultural Midwest region compared with other regions of the United States. Many studies have examined the relationship between farming and leukemia, but most have mainly focused on men. We examined the potential association between farm or rural residence and AML in the Iowa Women's Health Study. In 1986, 37,693 women who were free of prior cancer completed a lifestyle and health questionnaire, which included a question on the place of residence. Women were subsequently followed until 2002 for cancer incidence; 79 women developed AML during the time period. Women who lived on a farm at baseline were more likely (relative risk, 1.91; 95% confidence interval, 1.19-3.05) to develop AML compared with women who did not live on a farm. Further, women who reported living on a farm or in a rural area were twice as likely (relative risk, 2.38; 95% confidence interval, 1.33-4.26) to develop AML compared with women who lived in a city with a population of >10,000 people. These results provide evidence that women who live on farms or rural areas are at an increased risk of AML.  相似文献   
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The dissolution of 7 drugs from hydroxypropylmethylcellulose (HPMC) matrices have been examined to determine the time exponent (tn) required to produce linear dissolution profiles. A value of n = ˜ 0.67 was obtained for time-dependent release for soluble drugs, the precise values being 0.71, 0.65, 0.67 and 0.64 for promethazine hydrochloride, aminophylline, propranolol hydrochloride and theophylline, respectively. The insoluble drugs, indomethacin and diazepam, displayed values of n = 0.90 and 0.82 indicating a near zero-order release. Matrices containing tetracycline hydrochloride, however, showed a value of n = 0.45 and displayed complex release patterns and lower release rates than anticipated on the basis of solubility. Replacement of HPMC by calcium phosphate or lactose increased the dissolution rates of promethazine hydrochloride although the values of n were unchanged. Differences in release rates between lactose and calcium phosphate replacement occurred only when matrices contained high levels of the diluents. A straight line relationship existed between release rates and tablet surface area for HPMC tablets containing promethazine hydrochloride.  相似文献   
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Iron overload disorders involve excess accumulation of iron in body tissues as a result of hereditary and nonhereditary diseases. If left untreated, tissue iron deposition can result in organ damage. Treatment options such as phlebotomy, chelating agents, and erythrocytapheresis can prevent complications and target organ damage. Although phlebotomy is the gold standard for iron overload treatment in the setting of hereditary hemochromatosis, this procedure is usually not feasible for other iron overload conditions, especially those associated with anemia. With the introduction of newer, oral chelating agents, more options are available for patients refractory to or intolerant of parenteral chelating agents.  相似文献   
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视神经周围炎(OPN)是指涉及视神经鞘膜的一系列病理性炎症.OPN的经典三联征包括单侧视神经病变伴随疼痛和/或视盘水肿,此病症与其它视神经病变相似,导致诊断延迟和治疗欠佳.2016年1月,我们对发表于Medline和Ovid数据库的关键词为“视神经周围炎”的各种语言的文献进行了检索,共查找到60篇文献,发表于1956-2015年.两位作者(Tai ELM和Tevaraj JMP)分别对论文摘要进行了独立筛选,并筛选出相关文章.本次综述,我们强调OPN的特点,特别是OPN和视神经炎之间的临床差异.虽然大多数OPN的病例是特发性的,但仍需进行调查以排除特异性感染和继发性OPN的炎症原因.MRI是非常重要的检查方法,由于OPN视神经周围炎症的影像学诊断.糖皮质激素治疗可使症状与体征迅速好转,长期口服糖皮质激素并慢速递减可以降低复发的风险.  相似文献   
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BackgroundOxygenated right ventricular assist device (oxyRVAD) placement has become more streamlined with the introduction of the dual-lumen pulmonary artery cannula. Peripherally cannulated oxyRVAD may provide oxygenation support with right heart support as an alternative to venoarterial extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplantation.MethodsA single-institution, retrospective analysis was performed on patients placed on oxyRVAD with a dual-lumen pulmonary artery cannula with the intention of bridging to lung transplantation in 2019.ResultsFour patients with idiopathic pulmonary fibrosis were placed on oxyRVAD as a bridge to transplantation. Two patients were extubated and ambulated while waiting for a lung offer, and two patients required conversion to venoarteriovenous ECMO (VAV ECMO) from oxyRVAD. The median waiting time for extracorporeal life support (ECLS) was 42 h. All patients underwent double lung transplantation. Two patients stayed on oxyRVAD, and one patient was placed on venovenous ECMO (VV ECMO) after transplantation. Primary graft dysfunction score at 72 h after transplantation was grade 1 in three patients and grade 3 in one patient.ConclusionsPeripherally cannulated oxyRVAD with percutaneous dual-lumen venous cannula could be an ambulatory bridge for lung transplantation. It is unknown whether oxyRVAD is feasible as a long-term bridge to lung transplantation.  相似文献   
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