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991.
The history and etiology of inflammatory bowel disease which is characterized by two major disease processes: ulcerative colitis and Crohn's disease, remain unknown. Research is focussing on seven major areas of genetic, environmental and physiologic factors that apparently relate to this disease. Based on this background, a population based Inflammatory Bowel Disease Registry was established in 1987 in the Lehigh Valley area of southeastern Pennsylvania. Consent forms, patient data forms and protocols for operation and implementation were developed, and databases were designed to accommodate demographic, basic history, follow-up and relative history data. The databases were correlated with an IBD registry ID number which both enabled relational analyses and ensured confidentiality of data information. The registry continues to grow, providing feedback for both continued medical research and supportive information for IBD patients and their physicians.  相似文献   
992.
993.
Coronary artery disease was evaluated with tomographic and planar thallium imaging in 31 subjects who had undergone coronary angiography for assessment of chest pain syndrome. Coronary arteriography revealed significant coronary artery disease in 17; and 14 had normal coronary arteries. The sensitivity and specificity for planar imaging was 71% and 79%, and that for tomography, 94% and 79% respectively. The sensitivity and specificity figures for individual coronary artery lesion detection for planar imaging were 87/83 for LAD, 33/100 for LCX and 50/86 for RCA respectively, and for tomography the figures were 87/87 for LAD, 33/95 for LCX and 90/76 for RCA respectively. The use of coronary arteriography as a gold standard was considered by assessing its interobserver variability, which was 16%. The interobserver variability for thallium imaging was 8% and 3% respectively for tomographic and planar acquisitions.  相似文献   
994.
Three young children with characteristic fibroblastic tumors are presented. These comprised one case each of congenital fibrosarcoma, dermatofibrosarcoma protuberans, and fibrous hamartoma of infancy. Ultrastructural examination in each tumor revealed the presence of a peculiar intracisternal paracrystalline material that exhibited transverse periodicity between 18 and 22 nm. Elongated profiles lying within rough endoplasmic reticulum had a serpigenous outline. It is thought that this material is related to procollagen or its precursors and its presence may signify disorders of fibroblastic proliferation that may occur in fibrous tumors.  相似文献   
995.
Two cytologically uniform, light-microscopically undifferentiated carcinomas of the uterine cervix are described. The tumors were morphologically identical to nasopharyngeal lymphoepitheliomas, including the presence of an intense inflammatory stromal reaction with prominent lymphocytes, eosinophils, and plasma cells. One neoplasm occurred in a 29-year-old, was clinically Stage IB, and was successfully treated with radiation therapy, with 10-year disease-free follow-up. The second tumor developed in a 58-year-old, was clinically Stage IIIB, and resulted in the patient's death 17 months after diagnosis. When the malignant cells in these tumors were widely separated by inflammation, they could be easily overlooked or confused with lymphoproliferative lesions. Immunocytochemical stains were performed on one case. The tumor cells stained strongly for keratin and epithelial membrane antigen, but were negative for leukocyte common antigen, verifying their epithelial nature. Until the biologic behavior of this cytologically distinctive tumor is more clearly understood, it should be separated from conventional cervical cancers with prominent stromal inflammation.  相似文献   
996.
997.
Blood pressure and heart rate exhibit a circadian rhythm, with both rising rapidly during the morning hours and then decreasing throughout the day to a nadir around 3 AM. Current evidence suggests a possible link between cardiovascular events, such as myocardial infarction and sudden cardiac death, which have been shown to occur most frequently during the morning hours, and the rapid rise in blood pressure and heart rate during this same time period. We review data from ambulatory blood pressure studies to ascertain which antihypertensive agents provide the most satisfactory control of blood pressure and heart rate during the hours of 6 AM to 12 noon. Of the forms of drug therapy studied, labetalol, a combined alpha- and beta-blocker, and two calcium channel blockers, nifedipine and verapamil, appear to be the most effective in blunting the rise in arterial blood pressure during these critical morning hours.  相似文献   
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