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Healthcare executives closely adhere to many of the policies of the American College of Healthcare Executives but have significant reservations about others. That's the message of a survey designed to measure how College affiliates respond to issues ranging from organ donation and ethics committees to smoking policies and voluntary credentialing.  相似文献   
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Between 1980 and 1992, 457 consecutive patients with initial breast cancer entered two successive protocols combining neoadjuvant chemotherapy, hormonotherapy (tamoxifen) and locoregional radiotherapy (teleradiotherapy and boost by iridium) as exclusive locoregional treatment. Cytological diagnosis, hormone receptors, cytological grading were provided by fine needle aspiration. Both protocols included velbe, thiotepa, methotrexate, 5FU and adriamycin with some minor differences regarding the schedule of doses and their number during induction and during the consolidation phase. In both studies, over 50% patients had locally advanced breast cancer (IIb, IIIa or IIIb). Chemotherapy induced tumor regression over 50% in 91% patients of the first protocol (30% complete clinical remission CR) and in 94% patients of the 2nd protocol (40% CR): in this protocol 20 poor responders were given a rescue protocol (2 CR; 9 partial remissions). The 5 year actuarial rate of breast preservation is 94% and the 5 year actuarial rate of local relapses is 15%. The cosmetic results according to Danoff are excellent 20%, good 55%, mean 35%. Disease free survival and overall survival compare favorably to published data: they depend on TNM stages, tumor differentiation and chemotherapy induced early tumor regression.  相似文献   
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In vitro potencies of native and modified forms of salmon and mammalian gonadotropin-releasing hormone (GnRH) were studied in relation with their susceptibility to degradation by intact pituitary cells maintained in culture. The kinetics of degradation and the origin of the proteases involved in this process were examined. All the molecules tested (native and modified forms) were equipotent at doses between 10(-6) and 10(-7) M in inducing GtH release by cultured pituitary cells. On the other hand, their effectiveness differed at 10(-9) and 10(-8) M leading to the establishment of the following hierarchy of bioactivity: the native forms, LHRH and sGnRH, were the less potent, the fish analogues (DAla6Pro9Net)sGnRH and (DArg6Pro9Net)sGnRH were the more potent, and mammalian analogues with substitutions at position 6 and/or 10 were intermediate in potency. The native form sGnRH was weakly degraded while no degradation of the modified molecules was observed. The degradation of the native sGnRH occurred after 12 and 24 hr of incubation and the results indicate that the peptidases involved are released from the cells into the incubation medium.  相似文献   
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Abstract The i.v. inoculation of parental spleen cells into unirradiated adult F1 hybrid mice results in a graft-versus-host reaction (GVHR). In the strain combination B10D2±(B10.BRx B10.D2) F1, this reaction is associated with thymic injury and transient but profound cellular immune deficiency. We further analysed the immune status of these mice 60 days after GVHR induction. Phenotypic studies of spleen cells showed that these mice were re-populated with parental lymphocytes resulting in a high degree of chimerism (85%). At this time, the mice looked healthy and recovered a normal cytotoxic T cell response (CTL) against allogeneic cells. GVH chimeric splenocytes were unresponsive against F 1 hybrid cells in mixed lymphocyte culture (MLC), but exhibited anti-F1 CTL reactivity. We also analysed the anti-F 1 reactivity of these mice in vivo. GVH chimeric splenocytes were unable to induce GVHR after injection into a new F1 hybrid and F1 GVH mice specifically rejected F1 bone marrow (BM) cells after lethal irradiation. Grafting a neonatal parental thymus prevented the rejection of F1 BM cells and restored CTL alloreactivity. It is concluded that the chimeric state induced by GVHR is associated with a split tolerance and that a radiosensitive thymic-dependent mechanism is involved in maintaining self-tolerance in these mice.  相似文献   
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