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排序方式: 共有608条查询结果,搜索用时 31 毫秒
551.
552.
S Mukhopadhyay KA Macleod TJ Ong SA Ogston 《Acta paediatrica (Oslo, Norway : 1992)》2001,90(11):1299-1303
This study aimed to define the differences in lung function between British Caucasian and rural eastern Indian children, and to test the hypothesis that nutrition could account for such "ethnic" variation. To exclude confounders, a rural Indian setting was identified and children were screened for respiratory illness before lung function and nutritional characteristics were measured. Regression equations for this population have already been published. In this study, the lung function differences between rural eastern Indian ( n = 391) and mean predicted lung function for Caucasian children were characterized, matched for height and sex. In addition, stepwise multiple regression models were fitted to investigate the relative associations of lung function differences with body mass index (BMI), occipitofrontal circumference and age. Although the largest differences in the forced expiratory volume in 1 s (FEV 1 ) [girls 28.7 (27.3-30.1), boys 23.4 (22.2-24.6)] and forced vital capacity [girls 27.9 (26.4-29.4), boys 30.7 (29.6-31.9)] [values as mean difference in % predicted (95% confidence intervals)] ever reported between two populations were observed, differences in peak expiratory flow rate (PEFR) were small. BMI was strongly associated with inter-racial differences for FEV 1 for both sexes (boys β= -0.227, girls β= -0.353, p ≤0.001) and PEFR for girls ( β= -0.200, p ≤0.05) ( β= standardized coefficient).
Conclusion: Preventable nutritional factors may play a causal role in determining the FEV 1 differences between rural Indian and Caucasian children. As peak FEV 1 in youth influences respiratory morbidity in later life, it is important to define specific nutrient 1 deficiencies that may relate to poor FEV growth in these children. 相似文献
Conclusion: Preventable nutritional factors may play a causal role in determining the FEV 1 differences between rural Indian and Caucasian children. As peak FEV 1 in youth influences respiratory morbidity in later life, it is important to define specific nutrient 1 deficiencies that may relate to poor FEV growth in these children. 相似文献
553.
Background
Medical students develop interest in a specialty career during medical school based on knowledge and clinical experience of different specialties. How valid this knowledge is and how this knowledge relates to the development of preference for a specialty is not known. We studied their "subjective" knowledge of a specialty (students' reported knowledge) with "objective" knowledge of it (students actual knowledge as compared to reports of specialists) and their preference for this specialty at different stages of education, and used youth health care as a case study. 相似文献554.
555.
Oblique planes of section in MR imaging 总被引:1,自引:0,他引:1
Edelman RR; Stark DD; Saini S; Ferrucci JT Jr; Dinsmore RE; Ladd W; Brady TJ 《Radiology》1986,159(3):807-810
Magnetic resonance (MR) imaging allows freedom in choosing oblique planes of section and rotation of the image plane with respect to the frequency-encoded (F) and phase-encoded (P) dimensions. A general method is described for understanding geometric relationships between the fixed magnetic coordinate system, patient positioning, and the flexible observer's coordinate system. Oblique planes of section are clinically useful in studying organs with an axis of symmetry that is oblique to the magnet coordinate system, such as the heart. Rotation of the image plane can be used to move motion artifacts away from anatomic regions of interest, such as the liver and spine. Appropriate use of oblique section selection and image rotation can improve MR image quality and diagnostic value of the patient study. 相似文献
556.
Complications of laparoscopic nephrectomy: the Mayo clinic experience 总被引:12,自引:0,他引:12
Simon SD Castle EP Ferrigni RG Lamm DL Swanson SK Novicki DE Andrews PE 《The Journal of urology》2004,171(4):1447-1450
PURPOSE: We present the incidence of complications and conversions during laparoscopic nephrectomy performed for various indications and discuss methods to help prevent future complications. MATERIALS AND METHODS: From June 1999 to February 2003 at our institution 285 laparoscopic nephrectomy cases were performed, consisting of 113 radical nephrectomies, 101 donor nephrectomies, 27 simple nephrectomies, 23 partial nephrectomies and 21 nephroureterectomies. We reviewed the data base of patients who underwent laparoscopic nephrectomy to examine complications and analyze factors related to conversion to an open surgical procedure. RESULTS: Major complications occurred in 16 patients (5.6%). Major complications were surgical in 12 patients and medical in 4. Of the major surgical complications 3, 6, 1, 1 and 1 occurred during laparoscopic radical nephrectomy, donor nephrectomy, nephroureterectomy, simple nephrectomy and partial nephrectomy, respectively. The predominant major surgical complication was bleeding requiring conversion to an open surgical procedure. The overall conversion rate was 4% (12 patients), consisting of 6 emergency and 6 elective conversions. The remaining 27 patients experienced minor surgical or postoperative medical problems, such as urinary retention or wound infection. The mortality rate in our series was 0%. CONCLUSIONS: Laparoscopic renal surgery is becoming a routine procedure in the armamentarium of many urologists. Complications that are unique to laparoscopy exist but they should decrease with time with repetition and experience. We have learned many different precautions and procedures that should help decrease the risk of future complications associated with laparoscopic renal surgery. 相似文献
557.
558.
Mediastinitis following median sternotomy: CT findings 总被引:3,自引:0,他引:3
559.
The purpose of this study was to determine whether epitopes of the A, B, D, Fya, M, N, S, s, and K blood group antigens are present on microvesicle membranes shed by red cells during storage. Vesicles were isolated from outdated units of blood having and lacking the specified antigens. Diluted antisera were absorbed with fixed quantities of vesicles from red cells with the test antigen and red cells lacking that antigen (controls). The adsorbed and unadsorbed antisera were titrated and scored by using panel cells from persons known to be heterozygous for all the non-AB antigens. The mean titration scores following adsorption with the vesicles from A, B, D, M+N-, M-N+, S+s-, S-s+, and Fy(a+b-) units were appreciably lower than the control scores (0, 0, 3, 2, 2, 0, 4, and 4 vs. 19, 23, 34, 13, 12, 16, 18, and 29, respectively), which indicated the presence of these epitopes on the membrane of shed vesicles. The results following adsorption with K:1,2 vesicles were equivocal. 相似文献
560.