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International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change...  相似文献   
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In 1984, 154 physicians who had completed residencies in internal medicine at 15 major teaching hospitals in 1982 evaluated their residency training in ambulatory care. A majority of the physicians would have liked more experience in practical areas related to career planning and office management, more input from subspecialties such as orthopedics and dermatology, greater knowledge about the management of psychosocial problems, and more information about exercise and nutrition. Although many physicians also wanted more time devoted to several other topics, less than 20 percent recommended spending less time on 26 of the 27 topics being evaluated. Since these recommendations are similar to those reported in evaluation studies published over the past 25 years, it appears that training programs in internal medicine have not been successful in restructuring their curricula to meet many of the needs of practicing physicians.  相似文献   
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Age and immune response to a surgical stress   总被引:2,自引:0,他引:2  
We studied the effects of age and a relatively standardized stress (elective inguinal herniorrhaphy) on immune response. The patients included 20 men, ten at least 60 years old and ten younger, who were free of infection and illness and had not had prior surgery. Immune responses were measured one day before and five and 30 days after operation. We determined immunoglobulin levels, performed three delayed-hypersensitivity skin tests and a test for neutrophil chemotaxis, and measured lymphocyte responses to autologous cells, phytohemagglutinin-P (PHA), concanavalin A (Con A), and pokeweed. We also studied responses in 40 controls matched for age and sex. The responses to PHA and Con A were significantly lower in older patients than in controls at five days after operation; responses to Con A were still significantly lower at 30 days. Morbidity correlated with depressed immune responses in both age groups, even when there was no difference between older and younger patients.  相似文献   
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Conflicting published data regarding the role of macrophages and other cell types during the early stages of diabetes mellitus led us to further study this problem. To this end we diabetized mice, using low doses of streptozocin (STZ), 40 mg/kg body wt/day/5 days, and processed their pancreatic tissue for immunocytochemistry and ultrastructural observations; immunohistochemistry was performed on days 5 and 18 after the first STZ injection, and islets were observed ultrastructurally on days 5, 9, 10, and 18. Animals were tested for fasting serum glucose, and isolated islets were assayed for insulin secretion capacity. Immunohistology demonstrated that expression of major histocompatability complex class 2 antigens is strongly induced by multiple, low dose STZ treatments prior to impaired insulin release, and that different types of cells within the islet are capable of expressing Ia molecules. Ultrastructurally we found (a) a small number of macrophages (most probably resident monocytes/macrophages) containing B-cell debris, that were located close to either damaged or intact B cells; (b) a large number of recruited macrophages in a vascular or perivascular position; and (c) macrophages recognizable in the exocrine portion, close to the islets, occasionally containing exocrine cell debris. This led us to believe that recruited macrophages play an important role in the early islet-infiltrating stage.  相似文献   
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[Ca2+]i was measured using fura-2-loaded isolated catfish horizontal cells in the presence of L-glutamate and the glutamate analogs kainate (KA), quisqualate (QA), and NMDA. Caffeine was used to release Ca2+ from intracellular stores. Cell membrane potential was controlled with a voltage clamp to prevent activation of voltage-dependent Ca2+ channels in the presence of agonist. All excitatory amino acid agonists produced a rapid and sustained rise in [Ca2+]i with the order of potency being QA greater than Glu greater than KA greater than NMDA. The agonist-induced [Ca2+]i increase was blocked in reduced [Ca2+]o and by 6-cyano-7-nitroquinoxaline-2,3-dione and 2-amino-5-phosphonopentanoate, which are specific blockers for QA/KA and NMDA receptors, respectively. The metabotropic receptor agonist trans-1-amino-1,3-cyclopentanedicarboxylic acid (ACPD; 10-200 microM) had no effect on [Ca2+]i. Hill coefficients from curves fitted to concentration-response data suggested an amplification of the Ca2+ signal that was interpreted as calcium-induced calcium release (CICR) from intracellular Ca2+ stores. Caffeine (10 mM) produced a rapid transient rise in [Ca2+]i, confirming the existence of a Ca(2+)-sensitive store. Following caffeine-induced depletion of Ca2+ from intracellular stores, agonists were still able to produce increases in [Ca2+]i, confirming Ca2+ influx through the agonist-gated channel. The agonist-induced increase in [Ca2+]i was decreased following caffeine-induced depletion, confirming a process of CICR. These results are consistent with the hypothesis that excitatory amino acids can produce direct modulation of [Ca2+]i by influx through the agonist-gated channel and by CICR from intracellular stores.  相似文献   
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