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71.
Background  Reduced left ventricular ejection fraction (LVEF) is a risk factor for poor outcomes in patients with coronary artery disease (CAD). Mental stress-induced myocardial ischemia (MSIMI) also identifies a subset of CAD patients at increased risk for future cardiovascular events. Susceptibility to MSIMI in patients with CAD and reduced LVEF is unknown. Methods and Results  We enrolled 182 patients (67 women) with a mean age of 64 years and a documented history of CAD in this study. Baseline resting ejection fraction was determined by use of technetium 99m sestamibi gated single photon emission computed tomography. Abnormal LVEF was defined as less than 45% for men and less than 50% for women (based on published norms for our software [Cedars-Sinai Medical Center]). All participants underwent mental stress testing with a public speaking task. Rest/stress myocardial perfusion single photon emission computed tomography was performed via conventional methodology. Images were visually compared for number and severity of perfusion defects by use of a scoring method from 0 to 4. A summed difference score was calculated as the difference between summed stress and rest scores. A score of greater than 3 was considered abnormal. MSIMI developed in 19% of patients with normal LVEF and 31% of those with reduced LVEF. There is no statistically significant difference between the two groups (P=.11). Conclusions  CAD patients with left ventricular dysfunction are equally susceptible to MSIMI as those with normal LVEF. This study was supported by grants HL 070265 and HL 072059 from the National Heart. Lung, and Blood Institute. This material is also the result of work supported by resources and with the use of facilities at the Department of Veterans. Affairs Medical Center, Gainesville, Fla.  相似文献   
72.
BACKGROUND AND OBJECTIVES: Inguinal hernia repair is one of the most frequently performed pediatric surgical operations. Several pediatric laparoscopic inguinal hernia repair techniques have been introduced. But debate is unresolved regarding the feasibility of laparoscopy for treating pediatric inguinal hernias. METHODS: A retrospective cohort study enrolled 33 patients who underwent congenital inguinal hernia repair by either the new laparoscopic flip-flap technique or conventional open repair. Patients were divided into 2 groups according to the type of surgery: Group A included those who underwent the new laparoscopic technique, and Group B included those who underwent conventional open repair. RESULTS: Group A comprised 15 patients (mean age, 39 months), and group B comprised 18 (mean age, 44 months). Mean operative time was 47.5 minutes for Group A versus 27.5 minutes for Group B. Intraoperative complications for Group A included 1 case (7%) of vas deferens injury, and 3 cases (20%) in which the flaps were torn during suturing. In Group B, no intraoperative complications were encountered. In both groups, the mean postoperative hospital stay was 5.5 hours. Postoperative follow-up of 3 months revealed recurrence in 4 patients in Group A (27%), while there were no recurrences in Group B. CONCLUSION: Our preliminary experience shows unsatisfactory outcomes with laparoscopic flip-flap hernia repair in children. In spite of advancement in the application of laparoscopy in pediatric surgery, conventional open hernia repair is still the gold standard for children, in our experience. Future studies with more numbers and longterm follow-up should be conducted.  相似文献   
73.

Background  

Veno-arterial extracorporeal membrane oxygenation (ECMO) is a common modality of circulatory assist device used in children. We assessed the outcome of children who had ECMO following repair of congenital cardiac defects (CCD) and identified the risk factors associated with hospital mortality.  相似文献   
74.

Background  

While it is believed that total arterial grafting (TAG) for coronary artery bypass grafting (CABG) confers improved long-term outcomes when compared to conventional grafting with left internal mammary artery and saphenous vein grafts (LIMA+SVG), to date, this has not become the standard of care. In this study, we assessed the impact of TAG on medium-term outcomes after CABG.  相似文献   
75.
BACKGROUND & AIMS: Even though propofol has better recovery profile than traditional agents, its use is limited because of the perception of increased complication rates. Because an adequately powered trial comparing risk of propofol with traditional agents is lacking, we performed a meta-analysis of the current literature. METHODS: We searched Medline (1966-October 2004), EMBASE (1980-October 2004), and Cochrane controlled trials registry. The following 4 cardiopulmonary complications were assessed: hypoxia, hypotension, arrhythmias, and apnea. Procedures were divided into 3 groups: esophagogastroduodenoscopy group, colonoscopy group, and endoscopic retrograde cholangiopancreatography/endoscopic ultrasonography group. Pooled odds ratios for complications were calculated for all the procedures combined and then separately for the 3 groups. Random effects models were used for 2-proportion comparisons. RESULTS: Of the 90 citations identified, 12 original studies qualified for this meta-analysis and included 1161 patients. Of these, 634 received propofol, and 527 received midazolam, meperidine, and/or fentanyl. Most of the included studies were randomized trials of moderate quality and nonsignificant heterogeneity (Cochran Q = 4.81, P = .90). Compared with traditional sedative agents, the pooled odds ratio with the use of propofol for developing hypoxia or hypotension for all the procedures combined was 0.74 (95% confidence interval [CI], 0.44-1.24); for EGD, 0.85 (95% CI, 0.33-2.17); for colonoscopy, 0.4 (95% CI, 0.2-0.79); and for ERCP/EUS, 1.07 (95% CI, 0.38-3.01). CONCLUSIONS: Propofol sedation during colonoscopy appears to have lower odds of cardiopulmonary complications compared with traditional agents, but for other procedures, the risk of complications is similar.  相似文献   
76.
77.
目的在背根神经节(dorsal root ganglion,DRG)中等大小感觉神经元中可以观察到钙激活氯离子流(I_(Cl(Ca)))。在坐骨神经损伤模型中,在大多数大中神经元上诱导出类似的氯离子流。本文旨在探讨引起这个离子流的分子基础。方法使用常规的定量RT-PCR方法检测在DRG中三个基因家族的表达,这三个基因家族都具有诱导I_(Cl(Ca))的特点。结果在成年小鼠的DRG中,分别显示了在正常状态和坐骨神经损伤3天后CLCA,Bestrophin和Tweety基因家族成员的转录产物。结论mBestl和Tweety2可能在损伤诱导的DRG神经元I_(Cl(Ca))中发挥作用。  相似文献   
78.
Prednisone-Free Maintenance Immunosuppression—A 5-Year Experience   总被引:1,自引:0,他引:1  
Concern persists that prednisone-free maintenance immunosuppression in kidney transplant recipients will be associated with an increase in late allograft dysfunction and graft loss. We herein report 5-year follow-up of a trial of prednisone-free maintenance immunosuppression. From October 1, 1999, through January 31, 2005, at our center, 589 kidney transplant recipients were treated with a protocol incorporating discontinuation of their prednisone on postoperative day 6. At 5 years, actuarial patient survival was 91%; graft survival, 84%; death-censored graft survival, 92%; acute rejection-free graft survival, 84% and chronic rejection-free graft survival, 87%. The mean serum creatinine level (+/-SD) at 1 year was 1.6 +/- 0.6; at 5 years, 1.7 +/- 0.8. In all, 86% of kidney recipients with functioning grafts remain prednisone-free as of April 30, 2005. As compared with historical controls, recipients on prednisone-free maintenance immunosuppression had a significantly lower rate of a number of complications, including cataracts (p < 0.001), posttransplant diabetes mellitus (p < 0.001), avascular necrosis (p = 0.001), and fractures (p = 0.004). We conclude that prednisone-related side effects can be minimized in a protocol incorporating prednisone-free maintenance immunosuppression. Five-year graft outcome remains good.  相似文献   
79.
Spillage of gallstones may occur in the course of laparoscopic cholecystectomy. The incidence of this mishap and its consequences are variable. Ignored by many surgeons, stone spillage may be the source of significant morbidity many years after surgery. In this report, we describe the clinical course of a patient who presented with upper abdominal pain and swelling. The past history was positive for laparoscopic cholecystectomy 15 years earlier. After excision, the swelling was found to be a pseudocyst formed around spilled gallstones during a previous cholecystectomy. Apart from postoperative wound infection, the patient recovered well and remains so. Here, we discuss the problem and provide suggestions for spillage prevention and stone retrieval once spillage occurs.  相似文献   
80.
The effect of cow's milk consumption on childhood asthma has been debated for several years. This study attempts to provide further insight into this association through the use of a longitudinal study design. Newborns from parents with atopic history were recruited from Germany, Austria, and England (n = 696). For five repeated ascertainments, information was collected on cow's milk exposure, incidence of doctor-diagnosed asthma, and confounders. Generalized estimation equations, incorporating different models (concurrent, delayed, combined, and reverse causation), were used to determine this association. No association between cow's milk consumption and childhood asthma was found for the concurrent effects model (OR = 0.81, 95% confidence interval [CI]: 0.55, 1.20). In the delayed effects model, the direction of the association varied with time of follow-up. Thus, we stratified by period, which resulted in a significant protective delayed effect at 36 months (OR = 0.18, 95% CI = 0.06, 0.49). However, reverse causation negated this finding since the presence of asthma in prior months led to a reduction in further exposure to cow's milk (OR = 0.40, 95% CI = 0.16, 0.99). Hence, cow's milk consumption does not protect against childhood asthma. The apparent protection of cow's milk against asthma may result from parents of asthmatic children avoiding cow's milk, rather than actual prophylaxis.  相似文献   
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