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排序方式: 共有199条查询结果,搜索用时 312 毫秒
41.
Sierra Pugh Matthew J. Heaton Brian Hartman Candace Berrett Chantel Sloan Amber M. Evans Tebeb Gebretsadik Pingsheng Wu Tina V. Hartert Rees L. Lee 《Statistics in medicine》2019,38(11):1991-2001
RSV bronchiolitis (an acute lower respiratory tract viral infection in infants) is the most common cause of infant hospitalizations in the United States (US). The only preventive intervention currently available is monthly injections of immunoprophylaxis. However, this treatment is expensive and needs to be administered simultaneously with seasonal bronchiolitis cycles in order to be effective. To increase our understanding of bronchiolitis timing, this research focuses on identifying seasonal bronchiolitis cycles (start times, peaks, and declinations) throughout the continental US using data on infant bronchiolitis cases from the US Military Health System Data Repository. Because this data involved highly personal information, the bronchiolitis dates in the dataset were “jittered” in the sense that the recorded dates were randomized within a time window of the true date. Hence, we develop a statistical change point model that estimates spatially varying seasonal bronchiolitis cycles while accounting for the purposefully introduced jittering in the data. Additionally, by including temperature and humidity data as regressors, we identify a relationship between bronchiolitis seasonality and climate. We found that, in general, bronchiolitis seasons begin earlier and are longer in the southeastern states compared to the western states with peak times lasting approximately 1 month nationwide. 相似文献
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Rural health disparities in asthma care and outcomes 总被引:1,自引:1,他引:0
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TV Ajithkumar C Sivasankar K Ramachandran 《Journal of Medical Imaging and Radiation Oncology》2002,46(1):119-120
Orbital involvement at diagnosis in multiple myeloma is rare. Only a few a cases are reported with computed tomographic features. We report a case of orbital myeloma, and relevant medical reviews on computed tomography features are discussed. 相似文献
44.
We studied the role of interleukin (IL)-8 during engraftment after hematopoietic stem cell transplantation. In 40 consecutive patients undergoing either allogeneic marrow (n=32) or autologous peripheral blood stem cell transplantation (n=8), IL-8 plasma levels were serially determined. Median IL-8 concentrations peaked during the neutropenic phase and, subsequently, subsided to pretransplant levels in patients achieving engraftment. In all patients, we observed an inverse correlation of IL-8 with leukocytes (P<0.0001) and a direct correlation of IL-8 with the extent of neutropenia (P<0.0001). Four patients who developed graft failure showed sustained median IL-8 concentrations of >300 pg/mL together with persistent neutropenia. This marked elevation of IL-8 was statistically significant as early as day 11 after transplantation, at a time when no other evidence alluded to imminent graft failure. Our data suggest that IL-8 may play an important role during engraftment after hematopoietic stem cell transplantation. 相似文献
45.
人胰腺α-淀粉酶的cDNA克隆和原核表达的初步研究 总被引:4,自引:0,他引:4
目的 获得人胰腺α-淀粉酶(AMY2A)基因并进行原核表达。方法 采用基因工程技术,根据人AMY2A基因序列设计并合成特异性引物;从人胰腺组织中提取总RNA,反转录成CDNA第一链;逆转录-聚合酶链反应(RT-PCR)扩增人胰腺AMY2A基因,经BamH Ⅰ和Kpn Ⅰ双酶切、连接并插入原核表达载体pGEX-5T,构建pGEX-5T-AMY2A重组表达载体,在大肠杆菌BL21中异丙基硫代半乳糖苷酶(IPTG)诱导表达AMY2A蛋白。包涵体经尿素变性、复性及谷胱苷肽琼脂糖柱亲和层析纯化、AMY2A酶活性测定和免疫印迹分析。结果 重组质粒测序和酶切结果显示AMY2A基因已正确插入pGEX-5T,重组蛋白、复性及纯化产物SDS聚丙烯酰胺凝胶电泳(SDS-PAGE)在84 000处有一条明显的蛋白表达条带,AMY2A检测具有酶活性,免疫印迹分析表明重组蛋白具有人胰腺淀粉酶抗原性。结论 作者已克隆并在大肠杆菌中初步表达并获得纯化的谷胱苷肽转移酶(GST)-AMY2A融合蛋白。 相似文献
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The triggers and causes of asthma have long been topics of investigation by epidemiologists. The current concept of asthma and atopy is that the onset of the disease and its clinical course are determined by gene environment interactions; that is, those individuals who develop asthma are both genetically susceptible and receive appropriate environmental stimuli. One potential environmental factor that may relate to disease etiology is diet. This article will review the published evidence for the effects of dietary antioxidants on asthma incidence and disease control. 相似文献
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