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A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
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Pediatric chronic rhinosinusitis   总被引:2,自引:0,他引:2  
PURPOSE OF REVIEW: Pediatric sinusitis is prevalent, and the debate continues regarding how best to care for these children. Although acute sinusitis is commonly associated with an upper respiratory infection, the focus of this paper is on chronic rhinosinusitis in children. Research is often more difficult in children than adults, so many times one can learn from the adult literature and determine whether there can be application to the childhood population. RECENT FINDINGS: This paper looks at both medical and surgical treatment of chronic rhinosinusitis. "Maximal medical management" is often cited in the literature, but what this should consist of has never been clearly proved in the literature. Alternative medicine approaches as well as irrigation as an adjunct to care are discussed. Biomaterials are also be discussed. Recent outcome data are put in perspective. SUMMARY: Hopefully the reader will find the presentation stimulating. The paper does not promote surgery as a "cure all," and in the end, analysis will hopefully leave the reader more cautious but with a better understanding of this complex disease.  相似文献   
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OBJECTIVES: The frequency and consequences of major bleeding associated with anticoagulant prophylaxis for prevention of venous thromboembolism is examined. METHODS: We conducted a systematic review and meta-analysis of controlled trials that reported rates of major bleeding after pharmaceutical thromboprophylaxis in patients undergoing major orthopedic surgery. Thromboprophylactic agents were divided into four groups: warfarin/other coumarin derivatives (WARF), unfractionated heparin (UFH), low molecular weight heparin (LMWH), and pentasaccharide (PS). Meta-analysis was conducted comparing LMWH with each of WARF, UFH, and PS. The frequency of re-operation due to major bleeding was reviewed and combined with published costs to estimate the mean cost of managing major bleeding events in these patients. RESULTS: Twenty-one studies including 20,523 patients met inclusion criteria for the meta-analysis. No evidence of significant between-trial heterogeneity in risk ratios was found. Combined (fixed effects) relative risks (RR) of major bleeding compared with LMWH were WARF--RR 0.59 (95 percent confidence interval [CI], 0.44-0.80); UFH--RR 1.52 (95 percent CI, 1.04-2.23); PS--RR 1.52 (95 percent CI, 1.11-2.09). Seventy-one studies including 32,433 patients were included in the review of consequences of major bleeding. We estimated that the average cost of major bleeding is 113 dollars per patient receiving thromboprophylaxis. CONCLUSIONS: LMWH results in fewer major bleeding episodes than UFH and PS but more than WARF. These events are costly and clinically important.  相似文献   
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BACKGROUND: Spinal pain is common and costly to health services and society. Management guidelines have encouraged primary care referral for spinal manipulation, but the evidence base is weak. More economic evaluations alongside pragmatic trials have been recommended. OBJECTIVE: Our aim was to assess the cost-utility of a practice-based osteopathy clinic for subacute spinal pain. METHODS: A cost-utility analysis was performed alongside a pragmatic single-centre randomized controlled trial in a primary care osteopathy clinic accepting referrals from 14 neighbouring practices in North West Wales. Patients with back pain of 2-12 weeks duration were randomly allocated to treatment with osteopathy plus usual GP care or usual GP care alone. Costs were measured from a National Health Service (NHS) perspective. All primary and secondary health care interventions recorded in GP notes were collected for the study period. We calculated quality adjusted life year (QALY) gains based on EQ-5D responses from patients in the trial, and then cost per QALY ratios. Confidence intervals (CIs) were estimated using non-parametric bootstrapping. RESULTS: Osteopathy plus usual GP care was more effective but resulted in more health care costs than usual GP care alone. The point estimate of the incremental cost per QALY ratio was 3560 pounds (80% CI 542 pounds-77,100 pounds). Sensitivity analysis examining spine-related costs alone and total costs excluding outliers resulted in lower cost per QALY ratios. CONCLUSION: A primary care osteopathy clinic may be a cost-effective addition to usual GP care, but this conclusion was subject to considerable random error. Rigorous multi-centre studies are needed to assess the generalizability of this approach.  相似文献   
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OBJECTIVE: We set out to evaluate the prognostic factors in cervical adenocarcinoma metastatic to lymph nodes. STUDY DESIGN: We performed a retrospective review of 40 patients with cervical adenocarcinoma and lymph node metastasis from 1976 to 1996. RESULTS: Thirty-four patients had adenocarcinoma, and six had adenosquamous carcinoma. Median survival was 50 months. The median survival for patients with stage I disease was 69 months. Stage at diagnosis, treatment with radical hysterectomy, and receiving adjuvant therapy were associated with prolonged survival. A trend toward improved survival was noted with the use of concurrent radiation and chemotherapy as an adjuvant therapy. CONCLUSIONS: Adenocarcinoma metastatic to the lymph nodes does not have a uniformly poor prognosis, especially with early-stage disease. Improved survival was observed with the use of adjuvant therapy, specifically the use of combined chemotherapy and radiation after radical hysterectomy. The optimal therapy in this setting is yet to be determined. (Am J Obstet Gynecol 1998;178:1131-7.)  相似文献   
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