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991.
992.
Background: Obesity alone and rapid weight loss induced by bariatric surgery are recognized risk factors for the development
of cholelithiasis. The decision to perform prophylactic cholecystectomy at the time of bariatric operations remains controversial
and at the surgeon's discretion. Methods: From June 1998 to April 2001, 103 patients underwent Roux-en-Y gastric bypass (RYGBP)
in Hospital das Clinicas/Unicamp (SP). 88 of these 103 patients had their preoperative ultrasonography of gallbladder recovered.
19 of these 88 patients showed gallstones before RYGBP, and the remaining 69 did not have ultrasonographic evidence of cholelithiasis.
36 of these 69 patients were followed with ultrasonography during the 12 postoperative months. They were divided into 2 groups:
those who formed gallstones (n=19) and those who did not (n=17), to evaluate the importance of sex, age, preoperative BMI,
preoperative excess weight and postoperative percent excess weight loss as risk factors in the gallstone formation. Results:
Preoperative incidence of cholelithiasis in the 88 operated patients was 21.6% and postoperative incidence in the 36 patients
followed by ultrasonograph was 52.8%. There was no statistical evidence that postoperative gallstone formation is associated
significantly with the variables studied. Conclusion: This study confirms the high correlation between morbid obesity, rapid
weight loss and gallbladder disease. Predictive risk factors for gallstone formation were not found. 相似文献
993.
994.
Regional brain atrophy rate predicts future cognitive decline: 6-year longitudinal MR imaging study of normal aging 总被引:3,自引:0,他引:3
PURPOSE: To determine if medial temporal lobe (MTL) atrophy rate, assessed by using an automated procedure over the initial time interval of a 6-year, three-time-point longitudinal study, is predictive of future memory decline. MATERIALS AND METHODS: Healthy elderly subjects (age, >60 years) were administered a comprehensive battery of neuropsychometric tests and underwent magnetic resonance (MR) imaging at baseline and two or more follow-up examinations. The rate of brain atrophy between the baseline and first follow-up examinations was assessed by using an automated procedure that included spatial coregistration of the two images and regional brain boundary shift analysis. At final observation, the 45 subjects were separated into a group of those who did and a group of those who did not show objective evidence of cognitive decline. A forward stepwise logistic regression model was used to identify variables that predicted decline. RESULTS: Thirty-two subjects remained healthy, and 13 showed cognitive decline. Among subjects who showed cognitive decline, six declined after the second observation. MTL atrophy rate, through its interactions with sex and age, was the most significant predictor of decline. The overall accuracy of prediction was 89% (in 40 of 45 subjects), with 91% specificity (in 29 of 32 subjects) and 85% sensitivity (in 11 of 13 subjects). CONCLUSION: Among healthy elderly individuals, increased MTL atrophy rate appears to be predictive of future memory decline. 相似文献
995.
Lev-Ran O Mohr R Amir K Matsa M Nehser N Locker C Uretzky G 《The Annals of thoracic surgery》2003,75(6):559-1877
BACKGROUND: It has been advocated that skeletonized bilateral internal thoracic artery (BITA) grafting may be implemented safely in diabetics, thus bestowing these patients with the long-term benefits of this strategy. However, the feasibility of this approach in insulin-treated patients has yet to be determined. METHODS: One-hundred twenty-four insulin-treated diabetics, operated on between April 1996 and December 2001, were compared according to the surgical technique used: BITA (n = 50) or single internal thoracic artery (SITA; n = 74). In the latter, complementary grafts used were saphenous veins and radial arteries. RESULTS: The groups had comparable risk profiles, with the exception of more neurologic events in the SITA group (21% vs 4%, p = 0.008). There was no significant difference in 30-day mortality (6% vs 4%, p = 0.684), nor in the incidence of neurologic complications (2% vs 8%, p = 0.240). The rate of sternal infection was comparable (4% vs 2.7%, p = 1.000). Use of BITAs was associated with a lower return of angina (4% vs 20%, p = 0.025), less cardiac events (17% vs 38%, p = 0.01), and reduced cardiac mortality (none vs 10%, p = 0.04). Despite the similar 6-year survival (80.5% and 77.4%, p = NS), cardiac-related event-free survival was better in BITA patients (69% vs 23%, p < 0.0001). Multivariate analysis identified use of BITA as a protective factor resulting in less return of angina (p = 0.007) and improved cardiac-related event-free survival (p = 0.001). CONCLUSIONS: Skeletonized BITA grafting can be performed in insulin-treated diabetics at acceptable risk. This approach may confer improved cardiac outcome. Thus, it should be considered in selected patients. 相似文献
996.
Myocardial revascularization for acute myocardial infarction: benefits and drawbacks of avoiding cardiopulmonary bypass 总被引:3,自引:0,他引:3
Locker C Mohr R Paz Y Kramer A Lev-Ran O Pevni D Shapira I 《The Annals of thoracic surgery》2003,76(3):771-6; discussion 776-7
BACKGROUND: Coronary artery bypass grafting (CABG) for acute myocardial infarction (AMI) is associated with increased mortality compared with CABG in non-AMI patients. Operating without cardiopulmonary bypass (CPB) might reduce this mortality. METHODS: Between January 1992 and December 1998, 225 patients underwent CABG within 7 days of AMI, 119 with CPB and 106 without. The two groups were similar regarding age, gender, left ventricular dysfunction, and incidence of cardiogenic shock. Mean number of grafts per patient was 3.1 in the CPB group, and 1.7 in the no-CPB group (p < 0.0001). RESULTS: Operative mortality in the CPB group was 12% compared with 3.8% without CPB (p = 0.027). Independent predictors of operative mortality were preoperative use of intraaortic balloon counterpulsation (IABP), nonuse of internal thoracic artery (ITA) to the left anerior descending artery, and the use of less than three grafts. Mortality of patients operated on with CPB within 48 hours of AMI was significantly higher (16.5% vs 4.3%, respectively; p = 0.044). However, patients operated on after 48 hours had similar mortality (5.8% vs 3.4%, respectively). Follow-up ranged from 6 to 84 months. Five-year survival (Kaplan-Meier) of both groups was similar (81%). Patients operated on with CPB had similar rates of recurrent angina; however, they had lower prevalence of reinterventions (0.8% vs 6.3%; p = 0.03). CONCLUSIONS: Our study suggests that CPB can be used safely for most patients referred for CABG within the first week of AMI. However, for emergency patients operated on within the first 48 hours of symptom onset, we advocate avoiding CPB because it is associated with lower operative mortality. 相似文献
997.
Chorny M Levy D Schumacher I Lichaa C Gruzman B Livshits O Lomnicky Y 《Journal of pharmaceutical and biomedical analysis》2003,32(1):189-196
Benoxinate is a local anaesthetic used for ophthalmic applications. The aim of this study was to develop a rapid and simple stability-indicating method for the determination of benoxinate formulated for ophthalmic use, evaluate its long-term stability and identify its major degradation product. Benoxinate was eluted on a 10 microm Spherisorb phenyl column, 250 x 3.2 mm, with a mobile phase consisting of acetonitrile-buffer (pH 3.5) (35:65, v/v), pumped at 0.8 ml min(-1) flow rate. The buffer was composed of sodium dihydrogen phosphate (50 mM), sodium hydrogen sulfate (2.5 mM) and 1-heptanesulfonic acid sodium salt (5 mM). The analyte was quantified spectrophotometrically at 308 nm. The chromatograms of benoxinate formulations obtained by this method showed benoxinate (t = 4.5 min) well resolved from its degradation product (t = 2.3 min), which was separately identified by means of HPLC-MS as 4-amino-3-butoxybenzoic acid. The assay was demonstrated to have high accuracy, precision and linearity. The method was implemented in investigating the long-term stability of benoxinate 0.4% ophthalmic solutions. The method was found to be simple, quick and selective in determining benoxinate concentrations in fresh and aged preparations. 相似文献
998.
999.
One hundred young people aged 15 to 25 years were seen in the walk-in psychiatric emergency stroke of the Massachusetts General Hospital. Eighty-three had used alcohol and 58 had used drugs on at least six separate occasions. In most cases the use of these substances seemed incidental to the clinical presentation. However, serious abuse of drugs or alcohol was linked with a history of other behavioral disturbances such as delinquent acts, school drop-out and work instability. These behavioral abnormalities were usually apparent from an early age. This study indicates that certain individuals run a substantially higher risk than others of becoming heavily involved with drugs and alcohol. Established drug and alcohol dependence present formidable treatment problems. An emphasis on early prevention—by reaching these high risk individuals while they art still at school—may help to reduce the incidence of these disorders among the young. 相似文献
1000.
Increased hippocampal uptake of tumor necrosis factor α and behavioral changes in mice 总被引:4,自引:0,他引:4
Pan W Kastin AJ Rigai T McLay R Pick CG 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,149(2):195-199
Brain trauma may alter the function of the blood-brain barrier (BBB) and affect psychomotor activity. We have shown that the
transport system for tumor necrosis factor α (TNFα) at the BBB undergoes regulatory changes after spinal cord injury. In this
study, we show in CD1 mice that mild trauma by weight-drop to the right temporal region specifically increases the uptake
of blood-borne TNFα. This increase, measured by use of radiolabeled murine TNFα, occurred only in the right hippocampus 24 h
after injury and returned to normal at 1 week. There was no increase in the uptake of the vascular marker albumin at 1 h,
24 h, or 1 week postinjury, indicating that the BBB remained relatively intact. Human interleukin-1β, which does not cross
the BBB by saturable transport, showed no significant changes in brain uptake after trauma. Therefore, the selective entry
of TNFα in the injured right hippocampus may be explained by enhanced transport across the BBB. To explore the functional
relevance of this transport regulation, we measured mouse behavior by the staircase test. The number of rearings, mainly reflective
of exploratory behavior, decreased at 1 h and 1 day after injury but increased at 1 week after a 30-g weight-drop injury.
The number of stairs ascended, mainly indicative of locomotor activity, was unchanged at all times tested. We conclude that
mild, blunt brain trauma involving the hippocampus causes specific upregulation of TNFα transport and a selective change in
exploratory behavior. Although no causal relationship can be established at this time, the behavioral changes might be related
to the increased TNFα transport after trauma.
Electronic Publication 相似文献