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The purpose of this study was to assess the degree of consistency in student ratings of teacher effectiveness during the first year of medical school. Student ratings of teaching effectiveness represent a commonly used source of information that enters into the academic decision-making process. In medical school, student evaluations often represent a major source of information that is used in promotion and tenure decisions. It is essential that the precision of such ratings be ascertained so that decision-makers will know how much confidence to place in this source of information on teaching effectiveness. In this study, each member of a first-year medical school class was randomly assigned a two-digit identification number at the beginning of the spring semester, 1986. As the semester progressed students were asked to evaluate each full-time teacher in three major courses. Multiple instructors were utilized in each course (n = 10). Each teacher was evaluated immediately after lectures during the first (T1) and second (T2) halves of the course. Students evaluated the teacher a third time (T3) as part of the end-of-semester overall course evaluation. The teachers were evaluated on a short eight-item Likert-type scale that identified several key indicators of effective teaching. Students attached their anonymous identification numbers to individual ratings so that their responses could be matched in the analysis. The results indicate that medical students are only moderately consistent in the extent to which they evaluate teachers. This inconsistency varied by course and by instructors within courses.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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We have assembled a panel of monochromosomal somatic cell hybrids for use in gene mapping. DNA from each individual hybrid was used as a probe on normal human metaphases to identify the human chromosome and any fragments by reverse painting. To test the efficiency of the panel PCR amplification of DNA from the monochromosomal somatic cell hybrid panel was used in combination with human specific oligonucleotide primers to assign α-catenin (CTNNA1) and p21/WAFl to chromosomes 5 and 6 respectively. These genes were localized further using hybrids containing specific translocations to 5qll-qter and 6p21 respectively. We also developed primers to enable us to assign 17 ESTs sequenced by the HGMP Resource Centre. The hybrid panel was developed with support of the UK HGMP and the DNA is available to all registered users.  相似文献   
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Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm.  相似文献   
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Ten-year stability of cardiovascular responses to laboratory stressors   总被引:1,自引:0,他引:1  
In this study we examined test-retest stability of cardiovascular stress responses over a decade of the life span. Participants were 55 male college undergraduates. 19 years of age at initial testing, and 29 years of age at follow-up testing Stressors were a foot cold pressor and an aversive reaction time task. Cardiovascular measures included systolic and diastolic blood pressure, heart rate, and preejection period. For cold pressor, the magnitude and pattern of cardiovascular responses remained unchanged at the 10-year follow-up. For the reaction time task, the characteristic cardiovascular response patterns was preserved but with significant attenuation of magnitude. The present findings are consistent with previous observations of temporal stability but over a substantially longer test-retest interval. The long-term stability of stress responses is discussed in the context of stress test methodology, behavioral response demands, and maturation of the physiological systems involved in cardiovascular response expression.  相似文献   
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