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排序方式: 共有608条查询结果,搜索用时 15 毫秒
561.
Orchard TJ Temprosa M Goldberg R 《英国医学杂志》2006,9(3):177-178
问题:对于糖耐量减低者。用强化生活方式干预(ILS)或二甲双胍加推荐的标准生活方式干预。是否可以预防代谢综合征的发生或促进代谢综合征的缓解?[编者按] 相似文献
562.
OBJECTIVE: To determine safe and appropriate alarm limits for the Marquette 8000 pulse oximeter to prevent hyperoxic and hypoxic episodes in neonates. It is necessary to define these limits for each brand of oximeter because of the variance in nonuser adjustable calibration algorithms used in pulse oximeters. METHODOLOGY: Oxygen saturation values obtained from a Marquette 8000 pulse oximeter (SpO2) were compared with simultaneous arterial blood gas PaO2 values obtained from blood gas analysis, for 322 samples in 24 consecutive neonates (median 30 weeks' gestation). RESULTS: In order to prevent 95% of hyperoxic episodes (PaO2 > 90 mmHg), the upper alarm limit was 95% SpO2. Similarly, to prevent 95% of hypoxic episodes (PaO2 < 40 mmHg), the lower alarm limit was 95% SpO2. A sensitivity lower than 95% had to be accepted to develop an alarm range which prevented both hyperoxic and hypoxic episodes. To maintain PaO2 values between 40 and 90 mmHg, an appropriate alarm range of 94-97% SpO2 (90% sensitivity, 28% specificity) was established. CONCLUSIONS: The relative merits of high sensitivity versus high specificity should be considered when determining appropriate alarm limits. Alarm limits which represent a balance between sensitivity and specificity will minimise false alarms and provide a clinically practical range. It would be useful for this type of information to be available for each brand of oximeter, to assist the user in determining appropriate alarm settings. 相似文献
563.
LV Gregorio FP Giglio VT Sakai KC Modena BL Colombini AM Calvo CR Sipert TJ Dionísio JR Lauris FA Faria AS Trindade Junior CF Santos 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2008,106(1):19-28
OBJECTIVE: This study compared the clinical efficacy of 4% articaine (A200) and 0.5% bupivacaine (B200), both with 1:200,000 epinephrine, for lower third molar removal. STUDY DESIGN: Fifty patients underwent removal of symmetrically positioned lower third molars, in 2 separate appointments, under local anesthesia either with A200 or B200, in a double-blind, randomized, and crossover manner. Time to onset, duration of postoperative analgesia, duration of anesthetic action on soft tissues, intraoperative bleeding, and hemodynamic parameters were evaluated. RESULTS: A statistically significant difference between the time to onset of A200 (1.66 +/- 0.13 minutes) and B200 (2.51 +/- 0.21 minutes) was found (P < .05). There was no statistically significant difference in the duration of analgesia, whether the patient was subjected to osteotomy or not, regardless of the local anesthetic used (3 to 4 hours; P > .05). However, when patients received B200 they experienced a statistically significant longer period of anesthesia on the soft tissues as compared with when they had received A200 (around 5 hours and 4 hours, respectively, P < .05). The surgeon's rating of intraoperative bleeding was considered very close to minimal for both anesthetics. In the surgeries with osteotomy, the comparison between A200 and B200 showed statistically significant differences in the diastolic (64 mm Hg and 68 mm Hg, respectively, P = .001) and mean arterial pressure (86 mm Hg and 89 mm Hg, respectively, P = .031) when data from all the surgical phases were pooled. Additionally, the mouth opening at the suture removal was statistically different for A200 and B200 solutions (91.90% +/- 3.00% and 88.57% +/- 2.38% of the preoperative measure, respectively) when surgeries required bone removal (P < .05). CONCLUSIONS: In comparison with 0.5% bupivacaine, 4% articaine (both with 1:200,000 epinephrine) provided a shorter time to onset and comparable hemostasis and postoperative pain control with a shorter duration of soft tissue anesthesia in lower third molar removal. 相似文献
564.
565.
566.
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
567.
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568.
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
569.
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
570.