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41.
研究了由毕赤酵母胞内两步发酵法表达活性小分子阿片肽的条件.正交实验确定最佳生长条件为:甘油24g/L、酵母膏11g/L、蛋白胨22g/L、YNB 20ml/L,初始pH5.0.菌体密度可达2.46;以单因素实验确定最佳表达条件为:起始菌体浓度2.44,初始pH 6.25,每10h流加0.6%甲醇(v/v),表达时间96h.阿片肽250ml摇瓶产量由196mg/L提高至496mg/L.  相似文献   
42.
2,3,4-三氟苯胺经与EMME缩合、环合、氟乙基化、与N-甲基哌嗪缩合和水解反应制得氟罗沙星,前4步反应可被离子溶剂1-丁基-3-甲基咪唑六氟磷酸盐促进,如环合反应温度由300℃降至200℃,总收率61%.  相似文献   
43.
目的 本文研究了重组人胰高血糖素类多肽 1(7 36 )[rhGLP 1(7 36 ) ]对化学所致糖尿病模型动物的降血糖和促胰岛素分泌作用。方法 对四氧嘧啶型糖尿病小鼠及链脲霉素型糖尿病大鼠皮下注射不同剂量的rhGLP 1,分别于给药 4天后采血 ,收取血清 ,测定血糖及胰岛素值。结果 四氧嘧啶型糖尿病小鼠皮下注射 4 0、80 μg·kg-1rhGLP 1后 ,血糖值显著下降 (P <0 0 1) ,而 2 0 μg·kg-1剂量组则无显著性改变 ;链脲霉素型糖尿病大鼠皮下注射 2 8、5 6 μg·kg-1rhGLP 1后 ,血糖值显著下降 (P <0 0 5、P <0 0 1) ,而 14 μg·kg-1剂量组则无显著性改变。结论 rhGLP 1对实验动物部分 β细胞破坏的胰岛仍有促分泌胰岛素及降糖作用  相似文献   
44.
目的 总结伴IKZF1基因缺失儿童急性淋巴细胞白血病(ALL)的临床特征并观察提高化疗强度对其预后的影响。方法 2015年12月至2018年2月间确诊并按照中国儿童白血病协作组-ALL 2008(CCLG-ALL 2008)方案规范治疗的ALL患儿共278例,根据有无IKZF1基因缺失将其分为IKZF1基因缺失组和IKZF1基因正常组,IKZF1基因缺失组均接受CCLG-ALL 2008高危(HR)方案治疗,IKZF1基因正常组则按临床危险度分型接受不同强度化疗,比较两组的临床特征及无事件生存(EFS)率。结果 278例患儿中共24例(8.6%)检出IKZF1基因外显子大片段缺失。IKZF1基因缺失组初诊时WBC ≥ 50×109/L、BCR-ABL1融合基因阳性、诱导缓解治疗第15天微小残留病≥ 10%、微小残留病-HR、临床危险度-HR所占比例均高于IKZF1基因正常组(P < 0.05)。IKZF1基因缺失组3年EFS率(76%±10%)低于IKZF1基因正常组(84%±4%),但差异无统计学意义(P=0.282);其中,IKZF1基因缺失组-非HR(实际按CCLG-ALL 2008 HR方案化疗)的预计3年EFS率为82%±12%,低于IKZF1基因正常组-非HR(86%±5%),但差异无统计学意义(P=0.436)。结论 伴IKZF1基因缺失的儿童ALL早期治疗反应更差,提高化疗强度可能改善其预后。  相似文献   
45.
46.
Summary. Background: A pulmonary embolism (PE) is thought to be associated with atrial fibrillation (AF). Nevertheless, this association is based on weak data. Objectives: To assess whether the presence of AF influences the clinical probability of PE in a cohort of patients with suspected PE and to confirm the association between PE and AF. Patients/methods: We retrospectively analyzed the data from two trials that included 2449 consecutive patients admitted for a clinically suspected PE. An electrocardiography (ECG) was systematically performed and a PE was diagnosed by computer tomography (CT). The prevalence of AF among patients with or without a PE was compared in a multivariate logistic regression model. Results: The prevalence of PE was 22.8% (519/2272) in patients without AF and 18.8% (25/133) in patients with AF (P = 0.28). After adjustment for confounding factors, AF did not significantly modify the probability of PE (odds ratio [OR] 0.68, 95% confidence interval [CI] 0.42–1.11). However, when PE suspicion was based on new‐onset dyspnea, AF significantly decreased the probability of PE (OR 0.47, 95% CI 0.26–0.84). If isolated chest pain without dyspnea was the presenting complaint, AF tended to increase the probability of PE (OR 2.42, 95% CI 0.97–6.07). Conclusions: Overall, the presence of AF does not increase the probability of PE when this diagnosis is suspected. Nevertheless, when PE suspicion is based on new‐onset dyspnea, AF significantly decreases the probability of PE, as AF may mimic its clinical presentation. However, in patients with chest pain alone, AF tends to increase PE probability.  相似文献   
47.
48.
In the present study, we tested the ability of multidetector-row computed tomography (MDCT) and magnetic resonance imaging (MRI) to identify and retrospectively characterize atherosclerotic lesions in human ex vivo coronary arteries. Thirteen ex vivo hearts were studied with MDCT and MRI. MDCT-images were obtained with an isotropic voxel size of 0.6mm(3). MR images were obtained with an in-plane resolution of 195 microm and 3mm slice thickness. All images were matched with histopathology sections. For both modalities, the sensitivity for the detection of any atherosclerotic lesion was evaluated, and a retrospective analysis of plaque morphology according to criteria defined by the American Heart Association (AHA) was performed. At histopathology, 28 atherosclerotic lesions were found. 21 and 23 of these lesions were identified by MDCT and MRI, respectively. Both modalities detected a small number of false-positive lesions. After retrospective matching with histopathology, MDCT as well as MRI were able to differentiate typical morpholocigal features for fatty, fibrous or calcified plaque components. Using the information presented in this study, in vivo coronary artery wall imaging using MDCT as well as MRI could be facilitated and supported for future investigations on this subject.  相似文献   
49.
Bone marrow examination revealed a lipid-laden histiocytosis in seven patients undergoing long-term total parenteral nutrition necessitated by extensive short-bowel surgical resection. Clinical abnormalities occurred during this treatment which required bone marrow examination. These included hepatosplenomegaly and peripheral blood cytopenia; the median time to the detection of these abnormalities was 64 months.   The most striking change within the bone marrow was the presence of many pigment-laden histiocytes which had the typical morphology of sea-blue histiocytes seen in the so-called idiopathic sea-blue histiocyte syndrome. The occurrence of sea-blue histiocytosis in the bone marrow in association with long-term parenteral nutrition for short-bowel syndrome has not, to our knowledge, been reported previously and should now be considered in the differential diagnosis of bone marrow sea-blue histiocytosis.  相似文献   
50.
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