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101.
A double-blind, placebo-controlled randomized trial of 13-cis retinoic acid was performed to determine if the drug has a therapeutic effect in patients with myelodysplastic syndromes (MDS). Sixty-eight evaluable patients with MDS were randomized to receive a single, daily oral dose of either 13-cis retinoic acid (13-CRA, 100 mg/m2) or matching placebo. Treatment was continued, when possible, for a period of 6 months. Determination of response to treatment was based on clinical course, repeat bone marrow biopsies, and aspirates and blood counts (CBC) with WBC differential, platelet, and reticulocyte numbers at specified intervals. No significant difference was noted between the two treatment groups in response to test drug (P = .66). One patient (3%) in the 13-CRA group and two patients (6%) in the placebo group had a minor response. Approximately 30% of patients in both groups had progression of their disease, and progression-free survival was nearly identical. Greater than 90% of the patients receiving 13-CRA developed mild or moderate skin toxicity that was reversible with decreasing or discontinuing the drug. Our study did not find that 13-CRA exerts a beneficial therapeutic effect in patients with MDS.  相似文献   
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Chest X-ray films of 200 patients, aged between 90 and 102 years, were analysed for frequency of distribution and varying degrees of thoracic calcification. Calcification was found within the aortic wall in 89%, costal cartilage 79%, lung parenchyma 65%, lung hilum and/or mediastinum 64%, and tracheobronchial cartilages 55%. The degree of calcification was dependent on the tissue and sex involved (significant p less than 0.001). Calcification is of clinical value more often in younger patients than in the elderly. The classification, pathogenesis and differential diagnosis of thoracic calcifications are discussed.  相似文献   
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Using follow-up data from an interview survey representative for the German population from the year 1974 an inquiry was made into whether those who were told by a doctor that they had ”too low blood pressure“ at some point prior to the survey had better survival rates during the 16 year follow-up than those having not been so diagnosed. The method of Relative Survival based on cohort life-tables for all sex and age groups in Germany was used to compare the differential mortality effects. The result was surprising, despite the fact that only the diagnosis before 1974 was tested regarding its effect on future mortality: after making exact adjustments for demographic parameters, it was found that persons with ”low blood pressure“ survived markedly better than persons with normal or high blood pressure. If one considers smoking additionally, a strong effect of smoking on survival rates can be seen, but the advantage of persons with ”low blood pressure“ remains unchanged. The debate in medicine whether ”low blood pressure“ can be considered a disease or whether it justifies drug treatment at all, got an astonishingly clear answer.  相似文献   
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A system was developed to determine the potential role of infrared imaging as a tool for localizing anatomic structures and assessing tissue viability during laparoscopic surgical procedures. A camera system sensitive to emitted energy in the midinfrared range (3–5 μm) was incorporated into a two-channel visible laparoscope. Laparoscopic cholecystectomy, dissection of the ureter, and assessment of bowel perfusion were performed in a porcine model with the aid of this infrared imaging system. Inexperienced laparoscopists were asked to localize and differentiate structures before dissection using the visible system and then using the infrared system. Assessment of bowel perfusion was also conducted using each system. Infrared imaging proved to be useful in differentiating between blood vessels and other anatomic structures. Differentiation of the cystic duct and arteries and transperitoneal localization of the ureter were successful in all instances using the infrared system when use of the visible system had failed. This system also permitted assessment of bowel perfusion during laparoscopic occlusion of mesenteric vessels. These initial studies demonstrate that infrared imaging may improve the differentiation and localization of anatomic structures and allow assessment of physiologic parameters such as perfusion not previously attainable with visible laparoscopic techniques. It may thus potentially be a powerful adjunct to laparoscopic surgery. Received: 23 August 1996/Accepted: 14 October 1996  相似文献   
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Edelman  RR; Mattle  HP; Kleefield  J; Silver  MS 《Radiology》1989,171(2):551-556
A technique is described for rapid imaging of blood flow and dynamic measurement of its velocity. The method is a combination of bolus tracking and low-flip-angle gradient-echo cine angiography. This method provides precise determination of velocity with high temporal resolution in a single measurement. Unlike what occurs in phase imaging techniques, flow is displayed directly, eliminating potential errors that result from non-flow-related sources of phase shifts. Manipulation of raw data sets is avoided. Results obtained from a flow phantom, healthy volunteers, and a patient with an aortic aneurysm demonstrate the capability of the technique to track flow at low and high velocities and to differentiate flowing blood from thrombus. Because of its conceptual simplicity, rapidity, and lack of susceptibility to extraneous phase shifts, this technique may prove ideal for in vivo flow measurement and evaluation of flow patterns.  相似文献   
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