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141.
Two hundred open-heart cases were anaesthetized with a diazepam-ketamine combination. The results were excellent. A "Micro-Mini" drip technique insured low, even, but adequate dose levels of ketamine and less drug was used. Induction and maintenance are simple and smooth. Effects on the cardiovascular system and respiratory system are minimal. The margin of safety is wide and 100% oxygen can be used whenever needed.  相似文献   
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The authors examined intentional forgetting of negative material in depression. Participants were instructed to not think about emotional nouns that they had learned to associate with a neutral cue word. The authors provided participants with multiple occasions to suppress the unwanted words. Overall, depressed participants successfully forgot negative words. Moreover, the authors obtained a clear practice effect. However, forgetting came at a cost: Compared with the nondepressed participants and with the depressed participants who were instructed to forget positive words, depressed participants who were instructed to forget negative words showed significantly worse recall of the baseline words. These results indicate that training depressed individuals in intentional forgetting could prove to be an effective strategy to counteract automatic ruminative tendencies and mood-congruent biases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The crystallization of ZnO microrods by hydrothermal treatment of a suspension formed from reaction of zinc acetate and sodium hydroxide has been examined using scanning and transmission electron microscopy. Polycrystalline hexagonal ZnO microrods first appeared after 0.5 h reaction time at 120°C. These early stage rods were composed of stacks of hexagonal layers, each ~50 nm in thickness containing closely aligned assemblies of nanocrystallites <20 nm in size. Further growth of the microrods involved columns of nanoparticles extending from the basal layers of the preformed hexagonal stacks. Re‐crystallization produced single‐crystal microrods, many of which existed as twin particles.  相似文献   
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While androgens have important skeletal effects, the mechanism(s) of androgen action on bone remain unclear. Current osteoblast models to study androgen effects have several limitations, including the presence of heterogeneous cell populations. In this study, we examined the effects of androgens on the proliferation and differentiation of a novel human fetal osteoblastic cell line (hFOB/AR-6) that expresses a mature osteoblast phenotype and a physiological number (approximately 4,000/nucleus) of androgen receptors (AR). Treatment with 5alpha-dihydrotestosterone (5alpha-DHT) inhibited the proliferation of hFOB/AR-6 cells in a dose-dependent fashion, while it had no effect on the proliferation of hFOB cells, which express low levels of AR (<200/nucleus). In hFOB/AR-6 cells, co-treatment with the specific AR antagonist, hydroxyflutamide abolished 5alpha-DHT-induced growth inhibition. Steady-state levels of transforming growth factor-beta1 (TGF-beta1) and TGF-beta-induced early gene (TIEG) mRNA decreased after treatment of hFOB/AR-6 cells with 5alpha-DHT, suggesting a role for the TGF-beta1-TIEG pathway in mediating 5alpha-DHT-induced growth inhibition of hFOB/AR-6 cells. In support of this, co-treatment of hFOB/AR-6 cells with TGF-beta1 (40 pg/ml) reversed the 5alpha-DHT-induced growth inhibition, whereas TGF-beta1 alone at this dose had no effect on hFOB/AR-6 cell proliferation. Furthermore, treatment of hFOB/AR-6 cells with 5alpha-DHT and testosterone (10(-8) M) inhibited basal and 1,25-(OH)2D3-induced alkaline phosphatase (ALP) activity and type I collagen synthesis without affecting osteocalcin production. Thus, in this fetal osteoblast cell line expressing a physiological number of AR, androgens decrease proliferation and the expression of markers associated with osteoblast differentiation. These studies suggest that the potential anabolic effect of androgens on bone may not be mediated at the level of the mature osteoblast.  相似文献   
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BACKGROUND AND OBJECTIVE: To compare the estimated survival and disease-free survival between children with Ph1-positive chronic myeloid leukemia treated with allogeneic bone marrow transplantation or conventional chemotherapy. DESIGN AND METHODS: In this retrospective study we compared the results obtained in a group of 14 children who received allogeneic bone marrow transplantation (BMT) between 1983 and 1993, and another group of 27 children treated with busulfan, hydroxyurea or alpha-interferon during the same time period. Patients were transplanted at a median of 7 months from diagnosis and all except one were in their first chronic phase. Conditioning consisted in total body irradiation and cyclophosphamide in 12 cases, and busulfan was added in two. RESULTS: Of the 14 patients treated with BMT, two died of transplant-related complications and two relapsed 18 and 48 months after the BMT. Ten children remain alive and disease free at a median follow up of 60 months. The probability of DFS at 5 years is 70%. Of the 27 patients treated with chemotherapy, 22 have died at a median of 36 months from diagnosis. The probability of survival at 5 years is 5% versus 83% for the BMT group (p = 0.001). INTERPRETATION AND CONCLUSIONS: Allogeneic BMT is a safe and very effective treatment for Ph-positive CML in children. Patients who have an HLA-identical sibling donor must receive a transplant as soon as possible after being diagnosed.  相似文献   
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OBJECTIVE: To investigate the associations of individual and area-based socioeconomic indicators with cardiovascular disease risk factors and mortality. DESIGN: Prospective study. SETTING: The towns of Renfrew and Paisley in the west of Scotland. PARTICIPANTS: 6961 men and 7991 women included in a population-based cardiovascular disease screening study between 1972 and 1976. MAIN OUTCOME MEASURES: Cardiovascular disease risk factors and cardiorespiratory morbidity at the time of screening: 15 year mortality from all causes and cardiovascular disease. RESULTS: Both the area-based deprivation indicator and individual social class were associated with generally less favourable profiles of cardiovascular disease risk factors at the time of the baseline screening examinations. The exception was plasma cholesterol concentration, which was lower for men and women in manual social class groups. Independent contributions of area-based deprivation and individual social class were generally seen with respect to risk factors and morbidity. All cause and cardiovascular disease mortality rates were both inversely associated with socioeconomic position whether indexed by area-based deprivation or social class. The area-based and individual socioeconomic indicators made independent contributions to mortality risk. CONCLUSIONS: Individually assigned and area-based socioeconomic indicators make independent contributions to several important health outcomes. The degree of inequalities in health that exist will not be demonstrated in studies using only one category of indicator. Similarly, adjustment for confounding by socioeconomic position in aetiological epidemiological studies will be inadequate if only one level of indicator is used. Policies aimed at reducing socioeconomic differentials in health should pay attention to the characteristics of the areas in which people live as well as the characteristics of the people who live in these areas.  相似文献   
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