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IntroductionThe novel coronavirus disease (COVID-19) could cause a severe acute respiratory infectious disease, showing a high mortality rate of 12–45% among cases who required intensive care unit admission. COVID-19 pneumoniaPatients and methodsFor the purpose of identifying clinical manifestations and radiological findings of COVID-19 pneumonia, we reviewed all cases of COVID-19 pneumonia which were published by the homepage of the Japanese Association for Infectious Diseases from Feb 5 2020 until April 30 2020, including our cases. All patients were diagnosed based on positive results of the novel coronavirus-real-time RT-PCR with chest computed tomography (CT) findings.ResultsA total of 92 patients were enrolled in this study. The median age was 66 years (range 16–92 years). For all, 50 (54%) were males. The most common underlying disease was hypertension in 32 (36%). Any comorbidity was seen in 60 (67%). The mortality rate was 4 (6%). In terms of clinical symptoms on an initial visit, fever and cough were confirmed in 66 (72%) and 37 (40%). Forty-three (47%) had no respiratory symptoms. As for radiological findings by chest CT scan, ground-glass opacities (GGO)s, peripheral distribution, bilateral lung involvements were seen in 88 (96%), 76 (83%) and 78 (85%), respectively.ConclusionIt is difficult to diagnose as COVID-19 pneumonia due to poor respiratory symptoms. Chest CT findings typically show GGO, peripheral and bilateral shadows. Patients should have chest CT performed if suspected for early diagnosis and therapeutic intervention, resulting in a favorable outcome and prevention of secondary nosocomial transmitted infection.  相似文献   
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.学者论坛·在动物实验中解决临床难题···························,·······································································……顾玉东(3)基因〕:程  相似文献   
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逆转录-聚合酶链反应(RT-PCR)法是将PCR方法与逆转录法结合应用,可快速高效地扩增某一基因的全cDNA。类胰岛素生长因子-I(IGF-I)在人染色体中只有一个基因,全长超过45kb,并有内含子,其cDNA却只有几百个bp,为了表达得到IGF-I,本文利用RT-PCR方法,从胎肝提出的混合mRNA中,筛选并扩增了IGF-I的cDNA。经过分子克隆与测序,证明不需制备胎肝cDNA库,即可快速获得IGF-I的cDNA。  相似文献   
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We consider nested multiple response models which are used extensively in the area of pharmacometrics. Given the conditional nature of such models, differences in predicted responses are a consequence of different assumptions about how the models interact. As such, sequential versus simultaneous and First Order (FO) versus First Order Conditional Estimation (FOCE) techniques have been explored in the literature where it was found that the sequential and FO approaches can produce biased results. It is therefore of interest to determine any design consequences between the various methods and approximations. As optimal design for nonlinear mixed effects models is dependent upon initial parameter estimates and an approximation to the expected Fisher information matrix, it is necessary to incorporate any influence of nonlinearity (or parameter-effects curvature) into our exploration. Hence, sequential versus simultaneous design with FO and FOCE considerations are compared under low, typical and high degrees of nonlinearity. Additionally, predicted standard errors of parameters are also compared to empirical estimates formed via a simulation/estimation study in NONMEM. Initially, design theory for nested multiple response models is developed and approaches mentioned above are investigated by considering a pharmacokinetic–pharmacodynamic model found in the literature. We consider design for situations where all responses are continuous and extend this methodology to the case where a response may be a discrete random variable. In particular, for a binary response pharmacodynamic model, it is conjectured that such responses will offer little information about all parameters and hence a sequential optimization, in the form of product design optimality, may yield near optimal designs.  相似文献   
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目的:研究特发性脊柱侧凸(IS)患者椎旁肌组织中神经营养素3(Neurotrophin-3,NT-3)在核酸水平(mRNA)的表达情况。方法:随机选择19例IS患者,年龄12~19岁,平均14.3岁,Cobb角42°~80°(平均54°)。手术中取顶椎(T7~T10)凸侧、凹侧椎旁肌肉组织,采用半定量RT-PCR法检测NT-3 mRNA表达水平。取4例相同年龄段的椎间盘突出患者手术切口头端非病变部位椎旁肌肉组织作为对照。结果:对照组椎旁肌中NT-3的mRNA表达阳性率50%,相对表达量为0.0237±0.0158,IS组患者椎旁肌中表达阳性率63.16%,相对表达量为0.1213±0.0939,较对照组表达量增加(P=0.051)。9例Cobb角>50°的IS患者表达阳性率为44.44%,相对表达量0.0431±0.0359,和对照组无明显差异;10例Cobb角≤50°的IS患者中表达阳性率为80%,相对表达量为0.1604±0.0895,与对照组和Cobb角>50°的IS患者比较有明显增加(P<0.01)。结论:正常椎旁肌组织中NT-3在核酸水平微量表达,特发性脊柱侧凸患者椎旁肌组织中NT-3 mRNA表达增加,尤其在小角度IS患者中增加明显,提示IS患者中存在神经营养因子表达异常。  相似文献   
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