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71.
There is a well‐documented shortage of physician researchers, and numerous training programs have been launched to facilitate development of new physician scientists. Short‐term research training programs are the most practical form of research exposure for most medical students, and the summer between their first and second years of medical school is generally the longest period they can devote solely to research. The goal of short‐term training programs is to whet the students’ appetite for research and spark their interest in the field. Relatively little research has been done to test the effectiveness of short‐term research training programs. In an effort to examine short‐term effects of three different NIH‐funded summer research training programs for medical students, we assessed the trainees’ (N = 75) research self‐efficacy prior to and after the programs using an 11‐item scale. These hands‐on training programs combined experiential, didactic, and mentoring elements. The students demonstrated a significant increase in their self‐efficacy for research. Trainees’ gender, ranking of their school, type of research, and specific content of research project did not predict improvement. Effect sizes for different types of items on the scale varied, with the largest gain seen in research methodology and communication of study findings.  相似文献   
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Hall  FM; Storella  JM; Silverstone  DZ; Wyshak  G 《Radiology》1988,167(2):353-358
Carcinoma was found in 30% (119 of 400) of biopsy specimens obtained for mammographically suspicious but nonpalpable findings. The authors reviewed the mammograms of these 400 cases without knowledge of the biopsy results and placed each examination into one of four groups based on their suspicion for carcinoma: minimal (n = 82), slight (n = 91), moderate (n = 174), and high (n = 53). In 127 cases, mammograms showed either minimally suspicious calcifications (n = 33) or minimally (n = 49) or slightly (n = 45) suspicious masses. A 4.7% (six of 127) rate of carcinoma was found in these groups; five of the six cancers were in situ. Had follow-up mammography been done rather than biopsy for these 127 less suspicious lesions, it is probable that the delay in diagnosis would not have altered overall prognosis. In the remaining 273 patients, the positive predictive value of mammography for carcinoma would have risen from 30% (119 of 400) to 41% (113 of 273). The authors conclude that in the management of suspicious nonpalpable mammographic findings, the rate of carcinoma for lesions at biopsy can approximate 40%. This is almost double the rate of most published series.  相似文献   
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The importance of a positive family history as a primary risk factor for coronary heart disease was examined in a case history study. Of 792 consecutive male patients aged under 60 years who survived a first episode of unstable angina or myocardial infarction, 326 had a negative family history, 298 had a positive history, and in 168 a family history could not be established with certainty. There was no significant difference in the distribution of the three primary coronary risk factors--cigarette smoking, hypertension, and hypercholesterolaemia--between those with and those without a positive family history. The 133 subjects with a positive family history of premature coronary heart disease (occurrence in near relatives under 60 years) were significantly younger than those with a negative family history. It is concluded that there is little evidence to confirm a positive family history as an important independent risk factor for coronary heart disease, although there may be familial aggregation of subjects with a high susceptibility to the effects of the three primary risk factors, cigarette smoking, hypertension, and hyperlipidaemia.  相似文献   
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High-dose (HD) cytosine arabinoside (ARA-C) is more effective treatment than conventional-dose ARA-C regimens for patients with relapsed acute nonlymphocytic leukemia (ANLL). We report here that HD ARA-C given during the first remission of ANLL has resulted in long remission durations and a high proportion of patients who survive more than three years free of disease. From August 1979 to September 1983, 36 adult patients with ANLL in first remission received one to three courses of HD ARA-C (3 g/m2 by one-hour infusion every 12 hours for 12 doses on days 1 through 6) alone or with daunorubicin (30 mg/m2 for two or three doses on days 7 through 9). Three patients died of sepsis or hemorrhage during consolidation, and 14 patients have relapsed from five to 48 months after diagnosis. The remaining 19 patients are in continued complete remission (CCR) from 11 to 62 months. Denoting all deaths in remission as relapse, the actuarial probability of CCR is 42% at 62 months, with an apparent plateau in the survival curve. Of the first 22 patients treated, ten remain in CCR from 37 to 62 months with no therapy for at least three years. Due to its heightened anti-leukemic activity, HD ARA-C allows brief but effective consolidation of ANLL in first remission, with long-term disease-free survival comparable to other approaches.  相似文献   
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In 22 patients with malignancies, treated with high-dose chemoradiotherapy and autologous bone marrow transplantation (BMT), peripheral blood T cell subsets and functions were studied. In ten cytomegalovirus (CMV)-negative patients, CD4+ and CD8+ T cells (representing T cells of the helper/inducer phenotype and T cells of the suppressor/cytotoxic phenotype, respectively), recovered slowly and simultaneously. In 12 CMV-positive patients, however, CD8+ T cells recovered more rapidly than CD4+ T cells and rose to increased counts. No T cells with an immature phenotype (CD1+, OKT6+) were observed. Lymphocyte stimulation by herpes simplex virus infected fibroblasts (and by CMV-infected fibroblasts in CMV-positive patients) in contrast remained high and even increased after BMT in both groups. These data indicate that T cell recovery after autologous BMT is mainly due to proliferation of mature T cells present in the BM graft and not to generation of new T cells from T cell precursors.  相似文献   
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