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61.
62.
Ocular MR imaging and spectroscopy: an ex vivo study 总被引:2,自引:0,他引:2
Gomori JM; Grossman RI; Shields JA; Augsburger JJ; Joseph PM; DeSimeone D 《Radiology》1986,160(1):201-205
Six eyes, freshly enucleated because of choroidal melanoma, were imaged on a 1.4-T superconducting magnetic resonance (MR) imaging system, and relaxation times were calculated for various parts of the eye. Unfixed fresh tissue samples were obtained for nuclear magnetic resonance spectroscopy (NMRS) on a variable-field (0.19-1.4 T) resistive unit. Detailed ocular anatomy was demonstrated. The NMRS relaxation times correlated with the MR imaging intensity patterns. The sensitivity of MR imaging to states of hydration provides an excellent window for appreciation of ocular anatomy. 相似文献
63.
G. D. Lerman J. L. Blejer J. R. Oubia G. Carballal M. R. Nejamkis 《Journal of medical virology》1986,19(1):71-77
This study was carried out to determine the pathways along which two strains of Junin virus (JV), the pathogenic XJV and the attenuated XJC13V, reach the CNS following IP inoculation of 2-day-old rats. A sequential study of infectivity and antigen distribution in peritoneal macrophages, spleen, and brain was performed. Mortality was 85% with the former strain, but only 15% with the latter. At 4-7 days PI, XJV-infected animals had viral antigen in 10% of peritoneal macrophages. Viremia and spleen virus lasted for 10-15 days. Low brain titers were detected at day 7, with a peak at day 15. Brain antigen correlated with virus titers. In contrast, XJC13V-infected rats, macrophage antigen appeared later and to a lesser degree (1% of cells). Viremia and spleen virus were transient, while both the titer of brain virus and the viral antigen proved lower. Antibody titers were over twofold higher for XJ-infected animals. It is suggested that the different replication rate at the inoculation site could account for the greater ability of the XJV strain to reach the CNS. A greater antigen mass and/or more numerous antigenic determinants presented by the macrophage could explain the higher antibody titers found in XJ-injected rats, which were unable, however, to prevent viral spread. 相似文献
64.
Forty-three professional and amateur athletes with persistent shoulder pain that interfered with their sports activities were evaluated by computed tomographic (CT) arthrography. In 19 patients, glenohumeral instability (14 anterior, two posterior, three multidirectional) was diagnosed with CT arthrography based on the simultaneous presence of labral and capsular lesions. The findings were crucial in establishing the diagnosis of instability in six patients in whom the condition was not suggested or could not be confirmed clinically. Another significant injury consisted of labral lesions not associated with glenohumeral instability. These tears often involved the anterior and parasuperior segments of this structure. Other, less frequently detected lesions included segmental labral enlargement and several labra with abnormal orientation (everted labrum). Early onset of degenerative disease was present in many athletes, especially those with a long history of sports activity. CT arthrographic findings were correlated with arthroscopic or surgical results in 19 patients. 相似文献
65.
JJ Lefrere ; M Mariotti ; D Vittecoq ; B Noel ; AM Courouce ; P Lambin ; C Salmon ; P Rouger 《Transfusion》1991,31(3):205-211
The possible existence of human immunodeficiency virus type 1 (HIV-1) infection in asymptomatic seronegative at-risk individuals was investigated in a prospective study of 55 seronegative high-risk individuals (42 homosexual men and 13 heterosexual individuals) and 32 seronegative hemophiliacs treated with factor VIII or IX concentrates before viral inactivation by heat treatment and systematic screening of blood donations. Tests used include the polymerase chain reaction assay with three primer pairs (one in the gag region and two in the pol region) and tests for serum p24 antigen, anti-nef serology (Western blot), and five biologic markers frequently altered by HIV infection (CD4 lymphocyte count, serum beta 2-microglobulin and neopterin concentration, and serum IgG and IgA concentration). Although 91 of 92 HIV-1-seropositive persons were positive in testing with at least one primer pair, no positive result was observed in seronegative at-risk individuals or in 117 seronegative low-risk controls. No nef antibody was found in seronegative at-risk individuals or seronegative controls, but 44 (47%) of 92 HIV-1-seropositive persons had nef antibodies. These findings do not support the existence of frequent HIV-1 infection in seronegative at-risk individuals. 相似文献
66.
67.
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
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
68.
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
69.
G Sanclemente JJ Garcia JJ Zuleta C Diehl C Correa R Falabella 《Journal of the European Academy of Dermatology and Venereology》2008,22(11):1359-1364
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
70.