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排序方式: 共有1220条查询结果,搜索用时 15 毫秒
1.
Paul Wexberg MD BM Richard Pacher MD Suzanne Rdler MD Katharina Kiss MD Gilbert Beran MD Michael Grimm MD Gerald Maurer MD Dietmar Glogar MD FESC 《The Journal of heart and lung transplantation》2002,21(12):583-1263
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation. 相似文献
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J N Nankani M Northfield Y M Beran P D Richardson 《Current medical research and opinion》1990,12(3):198-206
An open, multi-centre, general practice study was carried out in 1661 asthmatic patients to assess the efficacy, in terms of symptom relief and changes in lifestyle, of budesonide and to record objective lung function changes and any adverse events. After a 1-week run-in period on any pre-trial anti-asthma medication, patients received either 200 micrograms or 400 micrograms budesonide twice daily by metered dose inhaler for 4 weeks. Peak expiratory flow rate (PEFR) was measured by the doctor on entry, after the run-in, and at the end of the study and patients were asked to complete diary cards on a daily basis to record compliance, bronchodilator usage and the severity of cough, wheeze and sleep disturbance, and weekly to record 5 lifestyle assessments, e.g. physical activity. Analysis of data from the clinic visits and 1375 completed diary cards showed that PEFR increased significantly from 321 +/- 3 l/min at the end of the run-in to 368 +/- 3 l/min at the end of the trial; 77% of patients had an improved PEFR. Bronchodilator use decreased significantly from 4.2 +/- 0.1 times/day during the run-in period to 3.0 +/- 0.1 times/day at the end of the study; 65% of patients used less bronchodilator. Significant improvements were recorded in all the symptoms and lifestyle indices monitored; 76% of patients improved in at least 5 of the 11 assessments. Treatment-emergent adverse events occurred in 103 (6%) of patients: none was classified as serious or unexpected. No sub-group of patients was identified in which the results were at variance from the full sample. It is concluded that budesonide improves patients' lifestyle and ability to carry out normal activities, as well as improving PEFR and reducing bronchodilator use, in mild to moderately severe asthmatics treated in general practice. 相似文献
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Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
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导数光谱系数倍率法测定多组分体系感冒清胶囊中盐酸吗啉胍的含量 总被引:1,自引:0,他引:1
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12). 相似文献
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Application of reflectance spectroscopy to the estimation of uric acid, urea and glucose: an evaluation of the Ames Seralyzer
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An original approach to the measurement of analytes in clinical chemistry has now become available, in which dry reagent strip technology is linked to measurement by reflectance spectroscopy. The present studies have evaluated the performance of the first of these test systems—for uric acid, urea and glucose, in serum—by comparison with conventional liquid chemistry methods. Satisfactory performance in terms of both precision and accuracy was obtained for all three test systems, the current “state-of-the-art” performance criteria being met; the Seralyzer system proved reliable and easy to use in the hands of trained operators. It should find a place as a “Stat” analyser in the laboratory, in specified wards and in Health Centres. 相似文献