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61.
Objective The effects of a computer-assisted instruction (CAI) tutorial program on learning clinical reasoning skills were compared in undergraduate dietetics students.Design A drill-and-practice program to control for time on task, a tutorial program, and a simulation program, as the test vehicle, were developed. The tutorial and simulation programs presented data on a patient with cardiovascular disease.Setting Subjects were tested in 30 undergraduate dietetics programs.Subjects Participants were 413 undergraduate diet therapy students enrolled in a coordinated program in dietetics (CPD) or a didactic program in dietetics (DPD).Intervention After completion of lectures on cardiovascular disease, subjects were given the drill-and-practice program plus a simulation test (group 1), the tutorial plus a simulation test (group 2), or the simulation test only (group 3).Main outcome measures Scores on the simulation test were compared. Variables included type of CAI, dietetics program, year in school, computer experience, and experience using a medical chart. Mastery of objectives related to lower- and higher-level clinical reasoning skills introduced in the tutorial program was compared.Statistical analysis One-way analysis of variance and Student-Newman Keuls tests were conducted to determine any differences among the three groups. Reliability was determined using the Kuder-Richardson Formula 20.Results The reliability coefficient of the simulation test was 0.93. Group 2 scored higher on the simulation test than group 1 or group 3. As a group, the CPD students scored higher than the DPD students. When CPD and DPD students were divided into the three experimental groups, there was no significant difference between the CPD and DPD student simulation scores. Group 2 mastered all objectives for lower-level reasoning skills and the higher-level decision-making objective better than groups 1 and 3.Applications/conclusions A computer tutorial program enhanced clinical reasoning skills in undergraduate dietetics students. This type of program could be used to supplement many topics taught in diet therapy and provide DPD students with experiential learning before their clinical intern practicums. J Am Diet Assoc. 1995; 95:868–873.  相似文献   
62.
Anti-carcinoembryonic antigen monoclonal antibody (MAb) CEA102 was produced by immunization with purified CEA and the specific accumulation of radiolabeled CEA102 in colorectal cancers was investigated by autoradiography of surgical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with 131I-labeled intact CEA102 or its F(ab')2. Primary tumor and liver metastases were successfully detected by external scanning with a gamma camera in 4 cases. Autoradiographic study of the surgical specimens using FCR showed predominant localization of 131I-labeled CEA102 in primary tumors and liver metastases in all cases. Even a small liver metastasis (0.5 cm) was clearly visualized in the autoradiogram by FCR. The pixel distribution curves of the density of the respective tissues in the autoradiograms by FCR showed the heterogeneity of the distribution of administered radiolabeled MAb in individual tumors, but the density of the tumors was higher than that of the normal tissues. In the quantitative distribution analysis of CEA102, the uptake of the primary tumor (mean 1.10%ID/kg) was ten-fold greater than that of the normal colon mucosa (mean G.10%ID/kg). These results revealed that the application of MAb has great potential in radioimmunodetection as well as in antibody-directed therapy.  相似文献   
63.
In this longitudinal study of a random sample of North Carolinians over the age of 65 and living in their homes, 325 blacks and 280 whites were examined and interviewed 18 months after baseline examinations. Coronal caries incidence was greater among whites than blacks. The increment due to teeth becoming root fragments were similar for both races; however, there were more newly crowned teeth among whites. Newly crowned surfaces were not used as part of the caries increment in logistic regression models to investigate potential risk predictors. For blacks, caries development over the 18-month period was associated with a higher lactobacillus score and more coronal caries at baseline, more previously filled coronal surfaces, and lack of active membership in clubs or other groups. For whites, having no self-reported tooth sensitivity, having a lower socioeconomic index score, taking antihistamine medications at baseline, and having the perception of more problems after the age of 40 than before were all associated with the development of coronal caries.  相似文献   
64.
Flexor tendon rupture as a complication of Colles' fracture is rare. We describe a case of attrition rupture of flexor tendons to the ring and little fingers after a malunited Colles' fracture, and we review the 17 previously reported cases.  相似文献   
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The comparison of disease risk in populations stratified by certain demographic variables provides important clues as to the underlying causes of disease. There are fundamental variations in the risk of occurrence of different cancers by gender, area of residence, and time of diagnosis. Men are, for instance, at considerably higher risk of developing most of the common cancers that occur in both sexes, and there are substantial variations in the occurrence of particular cancers in different regions of the World. This paper attempts to highlight some of these remarkable variations using cancer incidence data by sex, area of residence and year of diagnosis, emphasising the strong evidence that many of the contrasts can be appropriated to a number of modifiable “environmental” factors.Rates of cancer occurrence in the developed world are double that of less developed regions, although risk patterns are of very different magnitude and direction depending on the cancer site examined. Lung cancer is the most common neoplasm in men globally, but is overshadowed by prostate cancer in certain westernised countries, notably in the U.S. Cancers of the colon and rectum are important in the developed world, whereas stomach and liver cancer are common in developing areas.Men have systematically higher rates than women for the vast majority of the tumours that develop in both sexes, with the exception of thyroid cancer. There are also huge variations in the extent of the inequality: men have notably elevated risks, relative to women, of developing tumours of the head and neck, bladder, lung, oral cavity and liver.In Europe, incidence trends of lung cancer tend to be declining in men, although there is substantial between-country variation. In women, lung cancer rates are systematically on the increase in most Western, Southern and European countries. Trends in prostate cancer are increasing, as are trends in colorectal cancer (in both sexes), although more noticeably in Southern and Eastern Europe. Stomach cancer continues to fall in most European areas. Bladder cancer is decreasing in both men and women, apart from in Eastern Europe, whereas cancers of the kidney and non-Hodgkin lymphoma are steadily increasing in both sexes.We have estimated that men have better and more readily achievable prospects of avoiding death from cancer since they have lower rates of gender specific cancers, that are probably hormonal in origin, then women. Tobacco consumption plays a dominating role in the excess risk of cancer in men but it is apparent that the male excess disease burden can be effectively reduced by various prevention measures. As well as avoiding (or quitting) smoking, these include, moderating alcohol consumption, avoiding obesity, undertaking regular physical exercise, and maintaining a diet high in fruit and vegetables. The adoption of a healthier lifestyle will be of considerable benefit to the general health of both men and women, with an expectation of a major reduction in the burden of cancer, as well as other major diseases.  相似文献   
68.
Wilms tumor gene (WT-1) expression has been reported in many human cancers, including most ovarian and peritoneal serous carcinomas, but has not been studied in carcinomas of the fallopian tube. In this study, the authors evaluated the immunohistochemical expression of WT-1 in serous carcinomas of the fallopian tube and compared their reactivity with that of ovarian, peritoneal, and endometrial serous carcinomas. All primary serous carcinomas of the fallopian tube (13 cases), ovaries (25 cases), and peritoneum (3 cases) were reactive with the WT-1 antibody, whereas all five primary endometrial serous carcinomas were nonreactive. WT-1 reactivity in an unknown primary serous carcinoma is therefore suggestive of an extrauterine site. The marked difference in WT-1 staining raises the possibility of genetic differences between serous carcinomas arising in the endometrium compared with those arising in the ovaries, fallopian tubes, and peritoneum.  相似文献   
69.
Changes in MAP2 and clathrin immunoreactivity were studied in gerbil hippocampus after transient cerebral ischemia. MAP2 immuno-reactivity decreased significantly by 1 h in the subiculum-CA1 and CA2 areas which correspond to reactive change, while no decrease was observed in CA1 until day 4. Before the initiation of delayed neuronal death, MAP2 immunoreactivity was not changed in CA1. On the other hand clathrin immunoreactivity increased in the pyramidal cell layer of CA1 by 3 h after ischemia and remained high for 2 days. Clathrin immunoreactivity in the pyramidal cell layer of CA1 diminished after delayed neuronal death. The transient change of clathrin was noted especially in CA1 in the period prior to delayed neuronal death. These results imply an abnormal change in clathrin turnover after ischemia, which may participate in the pathogenesis of delayed neuronal death.  相似文献   
70.
CONTEXT: Health disparities between rural and urban communities are well documented. There are many suggested causes and many proposed solutions but no one-size-fits-all answer. The most successful community interventions have been introduced by communities themselves. However, before communities invest in such interventions, each group must identify and prioritize their needs. PURPOSE: This article describes the Hoshin facilitation method as a practical option assisting communities in assessing their needs and gaining consensus for future steps. METHODS: Thirty-four meetings were held in 11 rural communities in Hawaii using the Hoshin process to identify factors that impact rural health. Themes were identified by constant comparative analysis and thematic frequency described. Commonality of responses between communities was examined. Informal feedback was collected from meeting participants. FINDINGS: There was a great deal of commonality between community responses, with economic factors, drug use, lack of community leadership, lack of health care services and access to services, lack of healthy activities for youth, and poor public education being the most common issues noted. Group involvement in the meetings was high, and the facilitation method received positive feedback from participants. CONCLUSIONS: The Hoshin facilitation method is a very useful tool to help communities rapidly identify and prioritize areas for programmatic attention.  相似文献   
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