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101.
A case of neonatal Marfan syndrome is presented. The patient was noted to have cardiomegaly and tricuspid regurgitation on antenatal ultrasound scan. She was born with long, slender fingers and toes, an aged appearance and non-paralytic hypotonia. Echocardiogram revealed a dilated right atrium, right ventricle, dysplastic tricuspid valve and severe tricuspid regurgitation. She subsequently died of severe heart failure. Post-mortem examination showed the pathological features of lobar emphysema and cystic medial necrosis of the aorta. These features supported the diagnosis of neonatal Marfan syndrome. Nucleotide sequencing showed substitution of G by A at codon 1032 in exon 25 located in the long arm of chromosome 15. This resulted in the substitution of a cysteine by a tyrosine. A de novo mutation is suggested by the absence of affected family members.  相似文献   
102.
本文依据一组含有不同比例待测和干扰组分的标准混合液的吸收值,采用一元线性回归方法,在选择最佳测定波长对的同时建立标准工作曲线方程,使其更符合实际作品测定时的情况,提高了结果的精度和可靠性,并使计算量和实验工作量得以降低。应用于复方氨基比林注射液中三组分氨基比林、安替比林和巴比妥的同时测定,其平均回收率分别为99.8%,100.4%和99.8%,变异系数分别为0.59,1.48和1.05,结果优于卡尔曼滤波法、偏最小二乘法和目标因子分析法。  相似文献   
103.
应用误差反向传播学习算法(BP算法)对中药材雷公藤和昆明山海棠浸出物的红外光谱进行分类识别。网络为3层结构,输入节点为9个,隐层节点为21个,输出节点为1。分类结果与XIM-CA法基本一致。此外,本文还考察了网络参数间的相互关系。  相似文献   
104.
本文介绍以光学活性苏-1-(对硝基苯基)-1,3-二羟基丙胺-2为拆分剂,与消旋棉酚缩合,用常压柱色谱或溶剂结晶法分离得到两个光学纯的非对映体,然后分别水解得(+)和(-)-棉酚。  相似文献   
105.
Peak expiratory flow rates were measured in 124 normal elderly men (55-85 yr) using the Wright's peak flow meter. In the less than 60 yrs age group (n = 32; mean age 57.7 yr) the PEFR was 431 +/- 13 lpm, while for the group greater than 60 yr (mean age 69.0 +/- 6.0; n = 92), the PEFR value was 373 +/- 11 1pm. These values are similar to those reported in other Indian studies, suggesting that the ethnic variations amongst Indian subjects do not affect the PEFR. However, the reported values are lower than those observed in Europeans, but greater than those of Chinese. The PEFR regressed at a rate of 4.47 1pm/year increase in age, but is positively correlated to the subjects' height (cm), and their FVC and FEVI. The smokers had a significantly higher PEFR as compared with the non-smokers. This finding was contrary to what was expected.  相似文献   
106.
刘文英  周炜  盛龙生  安登魁 《药学学报》1988,23(12):933-937
本文采用Waters ILC-1离子液相色谱仪,IC-PAK A50×4.6mm色谱柱,pH6.61×10-3mol/L邻苯二甲酸溶液为流动相,430型电导检测器检测,由外标法和外标单点校正法同时测定了葡萄糖酸钙及其杂质(Cl-,SO42-)的含量。方法简便、快速,测定结果与中国药典法一致。外标法和外标单点校正法测定Cl-,SO42-的平均回收率为100.8%和100.2%,相关系数分别为0.9951(n=8)和0.9961(n=8)。  相似文献   
107.
Objective  The Indian subcontinent has among the highest rates of hypopharyngeal cancer worldwide. The purpose of this study was to examine the associations between the Indian diet and hypopharyngeal cancer. Methods  We used data from a hospital-based case–control study of 513 incident hypopharyngeal cancers and 718 controls from four centers in India. Dietary information was assessed using a 67-item semi-quantitative food frequency questionnaire. Intakes of related foods were combined across food groups and were categorized by quartile. We used unconditional logistic regression modeling, stratified by ever tobacco use, to analyze the association between food intakes and hypopharyngeal cancer. Results  Among persons who had ever smoked or chewed tobacco, protective associations were seen at the highest quartiles of total fruit intake (OR = 0.37, 0.20–0.69), curds (OR = 0.35, 0.17–0.69), and leafy green (OR = 0.25, 95% CI 0.13–0.51), root (OR = 0.22, 95% CI 0.11–0.43), and cruciferous vegetable intakes (OR = 0.41, 0.20–0.84). Results were similar, although not as robust, among persons who had never smoked or chewed tobacco. An increased risk of disease was seen among tobacco users who drank milk daily (OR = 1.84, 1.14–2.98). Conclusions  Dietary factors might contribute to the high risk of hypopharyngeal cancer observed in India.  相似文献   
108.
BACKGROUND: Second primary tumors (SPT) constitute a major threat to the survival of patients with laryngeal carcinoma. However, to the authors' knowledge little is known regarding the risk factors for developing SPTs or about the strategy to be followed to avoid them. METHODS: Eight hundred seventy-six male patients with laryngeal/hypopharyngeal carcinoma enrolled in a population-based, case-control study in 5 centers from South Europe during 1979-1982 were followed up to ascertain the occurrence of SPTs. Standardized incidence ratios were calculated to estimate the risk of SPT occurring in the cohort. Cox proportional hazard models were fitted to estimate the hazard ratio for development of SPTs in relation to use of tobacco smoking, alcohol consumption, and dietary habits before the first primary tumor. RESULTS: One hundred forty-five patients developed an SPT with an annual average rate of 2.1%. An excess risk of developing an SPT of the tongue, mouth, esophagus, and lung was observed. No elevated risks of SPTs were observed in other organs. Alcohol consumption strongly increased the risk of developing an SPT of the upper aerodigestive tract (UADT). Heavy cumulative cigarette smoking increased the risk of developing a lung SPT. A protective effect of high intake of citrus fruit was noticed for SPT in the lung, whereas high butter intake was associated with an increased risk for SPT of the UADT. CONCLUSIONS: Continuous medical surveillance was essential in the UADT and lung to reduce the risk from an SPT after initial laryngeal/hypopahryngeal carcinoma. Alcohol consumption before the first primary tumor was a risk factor for SPT of the UADT. The study suggested a protective role of citrus fruits in the development of a lung SPT.  相似文献   
109.
Smith  DK; Palek  J 《Blood》1983,62(6):1190-1196
Incubation of erythrocytes with the sulfhydryl reagent N-ethyl- maleimide (NEM) results in altered spectrin self-association and formation of dimers on the membrane. Skeletons isolated from these cells exhibit marked skeletal instability. In addition, NEM treatment induces increased thermal sensitivity of both cells and purified spectrin. These effects were not produced in aerobically incubated glucose-6-phosphate dehydrogenase deficient cells and were therefore presumably not due to depletion of intracellular reduced glutathione. These effects were produced by another permeant sulfhydryl reagent, monobromobimane, but not by its membrane-impermeant derivative. We conclude that spectrin sulfhydryl groups play an important role in spectrin self-association and thermal stability.  相似文献   
110.
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