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Ingestion of placenta and amniotic fluid has been shown to enhance opioid-mediated analgesia in rats produced by morphine injection, footshock, vaginal/cervical stimulation, and during late pregnancy. The present study was designed to investigate the effects of amniotic fluid ingestion on the characteristics of morphine dependency and withdrawal. Tail-flick latencies in Long-Evans rats were determined before and after repeated daily injections of morphine sulfate. It was found that ingestion of amniotic fluid after establishment of the morphine dependency, coupled with an injection of an otherwise ineffective dose of morphine, enhanced analgesia in morphine-dependent rats, and reversed hyperalgesia seen during withdrawal from morphine dependency.  相似文献   
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Over the past two decades, the role of radiolabeled monoclonal antibodies has been steadily growing in clinical practice, particularly for staging and locating a variety of neoplasms. This is due largely to the availability of these products in pharmaceutical quantities as well as the relatively low incidence of adverse reactions following the intravenous administration of antibodies to patients. One particular area of oncology where radiolabeled monoclonal antibodies are most likely to play an extremely important clinical role is in the evaluation of patients with colon and rectal carcinomas. In this report, we review the current utilization of tumor-associated monoclonal antibodies in the preoperative as well as postoperative screening of patients with colorectal carcinoma.  相似文献   
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Zusammenfassung Bei einer 37 j?hrigen, bisher gesunden Patientin entwickelte sich eine über 2 Monate progrediente Dyspnoe. Radiologisch und echokardiographisch zeigte sich eine massive Dilatation s?mtlicher Herzh?hlen mit biventrikul?ren Thromben und eine stark herabgesetzte Kontraktilit?t. Die Endomyokardbiopsien wurden von 2 Instituten als Myokarditis eingestuft. Im weiteren Verlauf entwickelten sich thrombembolische Komplikationen und ein therapierefrakt?res Pumpversagen, in dem die Patientin schlie?lich verstarb. Bei der Obduktion fand sich au?er einem dilatierten 600 g schweren Herzen mit biventrikul?ren Thromben ein klinisch bisher unbekanntes Ph?ochromozytom der linken Nebenniere. Die eingehende histologische und immunhistologische Aufarbeitung des Herzmuskelgewebes einschlie?lich Reevaluierung der Endomyokardbiopsien führte zur Revision der ursprünglichen Diagnose: Das Krankheitsbild der 37 j?hrigen Patientin war durch eine katecholamininduzierte dilatative Kardiomyopathie verursacht worden.   相似文献   
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We have found that neoplastic transformation alters the ability of cells to grow on substrata of tissue extracts, "biomatrices", enriched in extracellular matrix. Tumor cells were able to survive and grow at lower densities and on more types of biomatrices than normal cells. When plated at high densities (greater than 10(5) cells/60 mm dish), tumor cells attached with equal efficiency and grew at similar rates and to equivalent saturation densities on biomatrices derived from all tissues. However, at low (10(2)-10(4)/60-mm dish) seeding densities, the tumor cells grew only on certain types of biomatrix. For the various hepatoma and mammary carcinoma cell lines tested, the tissue specificity in clonal growth on biomatrices correlated with their organ site specificity for metastasis in vivo in immunosuppressed, athymic nude mice. Analysis of the effects of purified matrix components (adhesion proteins, collagens, glycosaminoglycans) indicated that only the glycosaminoglycans influenced density-dependent survival and growth of tumor cells with effects that differed with respect to the cell's metastatic potential. The results indicate that the ability of tumor cells to colonize specific tissues represents, in part, regulation of low density survival and growth by extracellular matrix and are suggestive that one of the matrix components responsible may be proteoglycans or their glycosaminoglycan chains.  相似文献   
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Natural killer (NK) cell activity was assessed in the peripheral blood of 20 patients with growth hormone (GH) deficiency due to a hypothalamic deficit of GH-releasing hormone (GHRH). All patients failed to respond to at least two provocative tests of GH secretion (GH below 7 ng/ml) but responded to a single GHRH iv bolus injection (1 microgram/kg body wt). In 14 of the 20 patients (20 determinations), lymphocyte subsets were also measured; in all patients the distribution of lymphocyte subsets was within the normal range. More importantly, NK cell activity in the 20 patients was significantly lower than in controls (P less than 0.01). To assess the in vivo effect of GH and GHRH on NK activity and lymphocyte subset distribution, immunologic tests were performed (i) before and after a single iv bolus injection of GHRH (1 microgram/kg body wt) in six patients; (ii) before and after 3 weeks of GHRH treatment (3-9 micrograms/kg body wt, one to four times daily) in five patients; and (iii) after 6 weeks of GH treatment (5 IU sc every alternate day) in one patient. Neither NK activity nor the distribution of lymphocyte subsets was altered during short-term GHRH administration. In conclusion, low NK activity is found in GH-deficient patients, and short-term administration of GH or GHRH fails to restore this immunological abnormality. This result suggests that the hypothalamus may be a regulator of NK activity in the human and that patients with hypothalamic deficiencies should be monitored for the development of discrete immunodeficiencies.  相似文献   
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Residents at the School of Medicine and Biomedical Sciences at the State University of New York at Buffalo (SUNY at Buffalo) expressed an interest in receiving instruction in teaching skills. In 1988, under sponsorship of the Graduate Medical-Dental Education Consortium, faculty and residents implemented an orientation program for 110 incoming housestaff. Residents received instruction in large-group teaching skills, bedside teaching, small-group discussion, and student evaluation. The program was rated positively by the residents, 5% of whom became instructors in the orientation program for the following year. Because of the program's structure, both faculty and housestaff receiving training in teaching skills, which may lead to an overall improvement in the teaching of SUNY at Buffalo's medical students.  相似文献   
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