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Antibody responses following vaccination usually are analysed by comparing geometric mean concentrations across levels of relevant covariates and by comparing the proportions of vaccinees responding. In the regression setting, the analyses are done on log-transformed concentrations, estimating geometric mean responses conditional on a vector of covariates. More detailed analyses examining the relationship of covariates to different parts of the response distribution may be performed through the application of asymmetric least squares estimation of regression percentiles. We present a method for accounting for correlation in percentile regression analyses of longitudinal antibody response data. We illustrate the procedures with measles antibody response data from Haitian children who participated in a randomized trial of high titre vaccines. The strongest dose and strain effects were seen in the low end of the antibody concentration distributions.  相似文献   
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高建华  文广伶  张其楷 《药学学报》1990,25(12):891-897
研究了强效抗胆碱药dl-3-(2-苯基-2-环戊基-2-羟基-乙氧基)-奎宁环烷的四个光学异构体的两种不对称合成方法,用HPLC检测了异构体含量,讨论了构效关系。  相似文献   
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Previous clinical use of the Rotablator(TM) In coronary artery disease has involved a sequential increase in burr sizes up to 2 mm in diameter and has often utilized balloon adjunct to achieve an optimal result. We report our experience and describe our technique using a single, large burr (2.25, 2.5, or 2.75 mm diameter) without balloon assistance. The burr size was selected to approximate 70–90 percent of the apparent normal lumen diameter. Thirty-one patients with 36 lesions of complex morphology (eccentric, irregular, calcified, ulcerated, at bends, at bifurcations, completely occluded, as well as balloon failures) were successfully treated with the Rotablator(TM). Results were assessed by computerized quantitative angiography. The percent diameter stenosis (mean ± SD) for the group was reduced from 69.8 ± 11.3% to 30.9 ± 10% (p < 0.001). The mean absolute diameter stenosis increased from 0.9 ± 0.3 mm to 2.2 ± 0.3 mm (p < 0.001). Angiographically visible dissections were seen in 4 patients and were uncomplicated in 2. One patient had a non-Q-wave myocardial infarction. A fourth patient had a presumed acute occlusion 36 hr after the procedure, necessitating emergency bypass surgery, but without Q waves on the electrocardiogram or wall-motion abnormalities on the echocar-diogram. Nitroglycerin was infused through the Rotablator(TM) catheter and has considerably lowered the degree and frequency of spasm. No other acute complications occurred. The mean procedure time using a single burr was shorter than when multiple burrs were used: 56.5 vs. 97.3 min, respectively (p < 0.05). The use of a single, large-size Rotablator(TM) burr is an effective method of treating complex coronary stenoses without balloon assistance and has an encouragingly low complication rate and short procedure time. © 1992 Wiley-Liss, Inc.  相似文献   
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Background. Primary adenocarcinoma of the larynx is a rare neoplasm. The incidence is reported as less than 1% of all laryngeal neoplasms in multiple series. Simultaneous primary adenocarcinoma and a solitary squamous cell carcinoma of the larynx is even rarer and only one case has been found on review of the literature. Methods. A case report of a 74-year-old man with a history of right-sided throat pain, odynophagia, and progressive hoarseness is presented with a review of the literature pertaining to this unusual case. Results. The patient was found to have three distinctly separate laryngeal lesions on direct laryngoscopy. Histopathologic diagnosis of adenocarcinoma was made on one of the three biopsied sites with the other sites being squamous cell carcinoma. Following Combined radiotherapy and surgical treatment, the patient has remained free of disease. Conclusions. Adenocarcinoma of the larynx is an infrequent and lethal disease. This case report and a review of the literature demonstrate that aggressive surgical management is indicated, although still may not result in improved survival. © 1994 John Wiley & Sons, Inc.  相似文献   
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Epidermal growth factor receptor and bladder cancer: a review.   总被引:2,自引:0,他引:2  
Recently, expectations have been raised that molecular biological studies of human tumours may be of value in helping to predict future clinical behaviour, in terms of therapeutic response and long-term survival. The epidermal growth factor receptor (EGFr) is a cell surface receptor for EGF and transforming growth factor-alpha which is overexpressed by a number of human tumours. This article principally reviews previous investigations of the role of the epidermal growth factor receptor in bladder cancer and examines methods of detection, the correlation between EGFr status and known prognostic indicators and the value of assessing EGFr status in predicting clinical outcome in patients with bladder cancer. Recent studies of the c-erbB-2 proto-oncogene in bladder cancer and of cell cycling using Ki-67 are included.  相似文献   
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