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61.
Knowledge and practices regarding tuberculosis: a survey of final-year medical students from Canada, India and Uganda 总被引:1,自引:0,他引:1
CONTEXT: Tuberculosis is one of the most common infectious diseases worldwide and is responsible for the largest number of deaths from a single infectious cause. OBJECTIVE: The objective of this study was to compare the knowledge of and practices regarding tuberculosis in final-year medical students at schools from endemic and non-endemic areas. SUBJECTS: Final-year medical students at McMaster University in Canada, the Christian Medical College in India, and Makerere University in Uganda. METHODS: A questionnaire consisting of 20 multiple-choice questions assessing knowledge, practices, and exposure. A total knowledge score (maximum=13) and a total practice score (maximum=5) were created for each study site. RESULTS: 160 questionnaires were returned; the response rate was 68.4% (65/95) for McMaster University, 39.7% (23/58) for the Christian Medical College and 78.3% (72/92) for Makerere University. Students from Makerere University had the highest knowledge scores but differences were non-significant after adjustment for patient exposure and curriculum time (F(2,153)= 1.80, P=0.16). Differences in practice scores, however, remained significant after adjusting for curriculum time and patient exposure (F(2,153)=5.14, P=0.006). Knowledge score (F(1,156)=5.05, P=0.02), patient exposure (F(1,153)=9.11, P=0.003), and curriculum time and patient exposure (F(2,153)=5.14, P=0.006) were statistically significant positive predictors of the total practice score. CONCLUSIONS: This study demonstrated significant differences in undergraduate exposure to tuberculosis, total knowledge, and practice competency at three medical schools in Canada, India, and Uganda. In general, the knowledge base and practice competency of all three graduating classes was adequate. 相似文献
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基因芯片技术是最近发展起来的新兴分子生物学技术,它的并行处理特点使大规模研究脑损伤后的基因改变成为切实可能。本文综述了新近用基因芯片技术在脑损伤后基因表达时序性改变及基因表达谱分析等研究中的应用。 相似文献
64.
Results of randomized controlled trials of low-versus high-osmolality contrast media 总被引:1,自引:0,他引:1
The authors reviewed 100 randomized controlled trials (RCTs) conducted in humans to compare safety or efficacy of new low-osmolality contrast media (LOM) with that of high-osmolality contrast media (HOM). Findings of the 43 RCTs judged to be of the highest quality suggest that the efficacy of LOM in imaging is equal or superior to that of HOM for all routes of administration. Heat sensation occurred less often with LOM for all routes and pain occurred less often with LOM for intraarterial routes. No differences were seen in nephrotoxicity or in frequency of nausea, vomiting, urticaria, bronchospasm, laboratory test abnormalities, or neurologic events. Greater cardiovascular changes were seen with HOM, including increased or decreased heart rate, increased left ventricular end-diastolic pressure, decreased systolic pressure, and QT prolongation, depending on route of administration. To demonstrate whether a reduction in clinically significant adverse outcomes truly occurs with LOM, trials will need to enlist larger numbers of patients and employ appropriate outcome measures. Future trials should stratify patients according to their risk of adverse reactions to provide better information about benefits of LOM in low- versus high-risk patients. 相似文献
65.
Isthmic spondylolysis of the lumbar spine: MR imaging at 1.5 T 总被引:4,自引:0,他引:4
The appearance on magnetic resonance (MR) images of the normal pars interarticularis in 13 patients was reviewed and contrasted with that of the pars in eight patients with spondylolysis. The pars defect usually had an intermediate signal intensity with all pulse sequences; however, this intensity was somewhat variable depending on the exact ratio of cartilage, fat, and fluid within each bone defect. The pars defect was best seen with spin-echo 600/20 (repetition time msec/echo time msec) images. In three cases, out-of-phase images showed the spondylolysis best, because of extension of fat to the borders of the defect. The sagittal view allowed one to separate spondylolysis from the joint space of posterior facets since the orientation of the defects is perpendicular to the facets; thus, a common pitfall encountered with cross-sectional axial imaging techniques is avoided. MR imaging poorly delineated bone fragments around the defect, which may produce nerve root impingement, but revealed other numerous complications that occur with spondylolysis, including spondylolisthesis and herniation of the disk above. 相似文献
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67.
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography. 相似文献
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70.
Childhood scoliosis: MR imaging 总被引:2,自引:0,他引:2
Nokes SR; Murtagh FR; Jones JD d; Downing M; Arrington JA; Turetsky D; Silbiger ML 《Radiology》1987,164(3):791-797
The spinal cords of 28 scoliosis patients between the ages of 1 month and 17 years were examined with magnetic resonance (MR) imaging. Complete visualization was obtained in all cases. In 15 patients (53%) neuropathologic abnormalities demonstrated by MR imaging significantly affected their clinical course, including tethered cords (n = 7), syringomyelia (n = 5), Arnold-Chiari I malformation (n = 4), spinal cord tumors (n = 2), Arnold-Chiari II malformation (n = 3), and diastematomyelia (n = 1). The advantages of MR imaging in the evaluation of the scoliotic spine in children include a high sensitivity for the occult conditions associated with scoliosis, good anatomic demonstration of the cord, and absence of bone artifacts. MR imaging is recommended as a primary imaging modality in scoliosis, following conventional radiography. 相似文献