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101.
Health-care case management places pressure on decision makers to adopt treatment strategies that promote economic efficiency and hence profitability. Traditional costeffectiveness analysis (CEA), where the objective is to calculate cost-effectiveness ratios, can better inform decision making in markets where prices and efficacy vary widely. However, the threshold at which a given therapy becomes economically efficient relative to competing therapies is not evident from cost-effictiveness ratios alone.
OBJECTIVE: To illustrate the use of spatial techniques for identifying efficient treatment options, using statin therapy in secondary prevention of coronary heart disease (CHD) as a case study.
METHODS: We used a Markov model of CHD epidemiology and treatment to estimate cost-effectivness of 13 statin regimens versus no therapy in secondary prevention of CHD. Comparative efficacy was assessed using data from a recent trial (CURVES) that included these regimens. Patients were assumed to have a history of CHD with risk factors similar to those observed in the trial. CHD event risk was estimated using new subsequent-event risk equations from the Framingham Heart Study. Effectiveness was measured alternatively as gain in life expectancy and CHD events averted.
RESULTS: At usual starting doses, atorvastatin therapy provided the largest life expectancy gain and CHD event avoidance at the lowest cost per life-year gained ($12,900 and $23,400 for men and women, respectively), followed by simvastatin ($17,700 and $31,700), lovastatin ($18,800 and $33,700), pravastatin ($22,600 and $40,200), and fluvastatin ($23,800 and $42,000). Any desired level of effectiveness can be obtained at lowest cost with atorvastatin.
CONCLUSION: Economic efficiency is enhanced when atorvastatin is used to treat some or all patients requiring statin therapy in secondary prevention of CHD.  相似文献   
102.
Headaches are common disorders usually examined by nonneurologists. In order to assess how primary headache patients (IHS groups 1, 2, and 3) are generally managed by nonspecialists, 414 patients were asked about their previous headache care. Correct diagnosis had previously been made in only 44.9%, 6.7%, and 26.7% of the migraine, tension-type headache, and cluster headache patients, respectively. The patients underwent 501 investigative procedures motivated by the headache, averaging 1.21 examinations per patient, mostly EEGs. Preventive treatment was largely overlooked irrespective of the headache type. It is concluded that scientific improvements in headache care may be ineffective unless educational programs improve headache knowledge in general.  相似文献   
103.
This session is intended for sharing and comparing computer software applications for research, management, and practice. Software applications will be demonstrated for decision analysis, cost effectiveness analysis, multiattribute utility computation, and assessing patient utilities. Desktop applications, will be discussed. Laptop and handheld computer software will be demonstrated. Pharmacoeconomic software allows data to be analyzed from different perspectives: patient, provider, hospital, managed care, and society. Software models also allow assessment of health care products or services from different quantitative perspectives: cost of illness, cost minimization, cost-benefit, cost-effectiveness, and cost-utility. The integration of decision analysis and spreadsheets will also be discussed. Software is utilized to collect information, analyze data, present findings, or educate managers, providers and patients. Pros and cons of each analytical and software approach will be discussed. Participants are encouraged to bring their own laptops to demonstrate their own software or related Internet offerings in an informal roundtable fashion. Software beta versions allowed; "viruses" discouraged.  相似文献   
104.
Background Among all the topical immunomodulators, vitiligo's mainstay therapy includes topical corticosteroids. Many other non‐immune theories have also been suggested for vitiligo's pathogenesis, but the role of oxidative stress has gained more importance in recent years. Objective To compare the effect of topical 0.05% betamethasone vs. catalase/dismutase superoxide (C/DSO). Study design Randomized, matched‐paired, double‐blind trial. Setting Dermatology Section, University of Antioquia, Medellín, Colombia. Subjects Patients (aged > 18 years or between 12 and 18 years) with parent's informed consent, with stable or active bilateral vitiligo. Intervention Topical 0.05% betamethasone or C/DSO. Methods Two lesions similar to each other in size were chosen. All assessments were made by two blinded investigators, and photographs were subjected to morphometry analysis. Main outcome Skin repigmentation by digital morphometry. Results Twenty‐five patients were enrolled in the study (21 women and 4 men). Mean age of participants was 40 years (range: 12–74 years). One patient on C/DSO experienced a mild local erythematous papular rash that self‐resolved. At 4 months of therapy, there was no statistical difference on the percentage of repigmentation between betamethasone and C/DSO (5.63% ± 27.9 vs. 3.22% ± 25.8, respectively, P = 0.758). After 10 months of therapy, the percentage of skin repigmentation increased to 18.5 ± 93.14% with betamethasone and to 12.4 ± 59% with C/DSO, but again, we found no statistical differences (P = 0.79). Discussion and conclusions Few studies have described objective methods to evaluate repigmentation among vitiligo patients. Digital morphometry provides an objective assessment of repigmentation in vitiligo. Objective vitiligo repigmentation with topical C/DSO at 10 months is similar to topical 0.05% betamethasone. Although a mild adverse effect was related to the use of C/DSO, such finding was not severe enough to discontinue treatment.  相似文献   
105.
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Manco  LG; Kavanaugh  JH; Fay  JJ; Bilfield  BS 《Radiology》1986,159(1):147-151
A total of 209 patients underwent prospective axial computed tomography (CT) examinations of the knee to evaluate the ability of this technique to identify and characterize knee menisci in patients believed to have meniscus tears. Of the 359 knees examined, 105 subsequently underwent arthrography, arthroscopy, or arthrography and arthroscopic surgery. In this group, the sensitivity of CT was 88.5%, specificity was 95.5%, and accuracy was 91.5%. Although axial CT is a sensitive and effective method for the detection and characterization of tears involving the medial and lateral menisci, purely horizontal or nondisplaced peripheral tears may be difficult to demonstrate.  相似文献   
108.
Human blood groups: incidental receptors for viruses and bacteria   总被引:2,自引:0,他引:2  
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109.
The serum of EH reacted with all red cells (RBCs) except her own, ficin- or trypsin-treated red cells, and En(a-) red cells. This reactivity defined an anti-EnaTS specificity. The red cells of the proposita typed as M-N+S-S+, Vw+Mur-Hil-Hut-Anek-Lane-, Wr(a-b+), EnaKT+. Red cells of five relatives were Vw+ and positive with her serum. Titration studies suggest that EH is genetically an MiI homozygote and that her Vw+ relatives are MiI heterozygotes. There is no history of consanguinity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting studies have agreed with the serologic observations. A variant sialoglycoprotein of faster mobility than normal glycoprotein A, but no normal glycoprotein A, was detected on her red cells. Treatment with N-glycanase did not alter the mobility, which indicated that there was no N-glycosylation of residue 26. These findings are in agreement with the reported properties of the Mi.I-specific glycoprotein A. The relatives' Vw+ red cells showed the variant sialoglycoprotein and normal glycoprotein A. EH appears to be the first reported MiI homozygote.  相似文献   
110.
The survival of transfused red cells (RBCs) diminishes with time of in vitro storage in blood banks, but the molecular mechanisms underlying the slow but incessant deterioration are incompletely understood. To investigate the possibility that impaired resistance to autologous complement attack could play a role in this phenomenon, packed RBCs stored for variable periods were assayed for decay-accelerating factor (DAF) and CD59, two glycoinositol-phospholipid (GPI)-anchored, membrane- associated complement regulatory proteins that function physiologically to protect blood cells from autologous complement activation on their surfaces. Immunoradiometric and flow cytometric assays employing DAF and CD59 monoclonal antibodies showed that levels of both surface proteins gradually declined over 6 weeks. Digestion analyses with phosphatidylinositol-specific phospholipase C, an enzyme that releases GPI-anchored proteins from cell surfaces, showed that DAF and CD59 molecules with GPI anchors containing unacylated inositol were preferentially lost. These findings suggest: 1) that DAF and CD59 molecules with acylated GPI anchors are more stable in RBC membranes than are molecules with unacylated GPI anchors, and 2) that DAF and CD59 loss may participate with other membrane alterations that occur during in vitro storage in compromising the survival of transfused cells.  相似文献   
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