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991.
Phenytoin has known immunosuppressive properties, and a recent pilot study has indicated that it may have a second line effect in rheumatoid arthritis (RA). To evaluate this role 60 patients with active RA were randomly allocated to receive either oral phenytoin or intramuscular gold. The two treatment groups were comparable at the outset (Mann-Whitney U test). Twenty four patients completed 24 weeks of therapy in each group and no unexpected side effects were encountered. All variables except haemoglobin (Hb) improved significantly in the gold group while in the phenytoin group significant improvement was limited to articular index, erythrocyte sedimentation rate (ESR), and Hb. Between group comparison (Mann-Whitney) at week 24 showed a significant advantage of gold over phenytoin for pain score and morning stiffness. Thus phenytoin appears to exert a less potent second line effect than gold and is unusual in influencing laboratory indicators of disease activity more than clinical variables. This is likely to limit its usefulness as a second line drug in RA.  相似文献   
992.
Preliminary results from the June 1991 flight of MAX are presented. Simultaneous observations were made in bands centered at 6, 9, and 12 cm-1 with a bolometric receiver operating at 300 mK. The experimental sensitivities are the highest reported at angular scales of 0.3 degrees to 1.0 degrees. Interstellar dust is observed to have an emissivity [symbol, see text] nu 1.4+/-0.3 and to correlate with the Infrared Astronomical Satellite (IRAS) 100- map. After removal of emission from interstellar dust, 1.3 hr of integration on a 6 degrees scan yields an upper limit of temperature difference Delta T/T < 2.6 x 10(-5) at a Gaussian autocorrelation function centered at 0.5 degrees. The experiment and data analysis are described.  相似文献   
993.
994.
Citrate synthase from human heart was purified by affinity chromatography with Sepharose-ATP. The molecular weight (100 000) and presence of two presumably identical subunits do not differ from other mammalian citrate synthases. However, the kinetic constants, and immunologic characteristics of the enzyme, differed from findings from other mammalian citrate synthases. The Km values for acetyl CoA (0.4 μm) and oxaloacetate (0.25 μm) were about an order of magnitude lower than that previously found for other mammalian (and eucaryotic) citrate synthases. The kinetic constants for the reverse reaction, Km for citrate (420 μm) and CoA (70 μm) were of similar magnitude to the values for other mammals. Anti-human heart antiserum developed a single precipitin line in an Ouchterlony plate against a heart extract, no precipitin line with brain, and a precipitin line with spurs against liver and kidney extract. Following myocardial infarction in men, the enzyme appeared in peripheral blood rarely and in low concentration in contrast with earlier experiences with experimental infarction in dogs.  相似文献   
995.
Urotensin II has vasoconstrictive and negative inotropic effects, suggesting a possible role in circulatory regulation and pathophysiology of heart failure. We developed a sensitive specific RIA and measured plasma urotensin II in patients with heart failure and in controls. Plasma urotensin II was higher in heart failure patients (mean 3.9 pmol/L [SD 1.4]; than in controls (1.9 pmol/L [0.9]; p<0.0001). The role of urotensin II in heart failure, however, has yet to be defined.  相似文献   
996.
The diagnosis of plasma cell leukaemia, a rare disorder with an aggressive clinical course and poor prognosis, is not always straightforward and may be dependent on the results of immunophenotyping. Samples from two cases of plasma cell leukaemia have been issued by the UK NEQAS for Leucocyte Immunophenotyping Scheme during the last 5 years and on each occasion a significant number of laboratories failed to make the correct diagnosis. The details of the two samples issued and the results of both surveys are presented. The data highlights the need to adhere to guidelines for immunophenotyping, with respect to using the correct antibody panels, the importance of data interpretation in conjunction with morphological appearance as well as the need to participate in external quality assurance schemes.  相似文献   
997.
998.
The prevalence distribution of hypertension: Connecticut adults 1978-1979   总被引:1,自引:0,他引:1  
The results of the first Connecticut Blood Pressure Survey are reported. It was found that sharp differences exist in the prevalence of hypertension by age and sex but that race differences are much less than previously reported for United States populations. Differences were also found between men and women with respect to the patterns of treatment and control. Age differences in treatment and control are noted. The findings reported are based on a statewide probability sample for which the target population exceeded 2 million persons. Because of the complexity of sampling such a population an extensive discussion of the survey method is given.  相似文献   
999.
A major limiting factor for percutaneous coronary interventions carried out via the femoral route is the time it takes to achieve femoral artery hemostasis and subsequent mobilization. Discharge from hospital usually occurs the following day. In this pilot study, we assessed the feasibility of mobilization at 4 hours and same-day discharge from hospital of selected elective patients undergoing intracoronary stenting using the Angio-Seal Vascular Closure device. Seventy-five patients (56 +/- 10 years) with stable single-vessel coronary disease scheduled for elective coronary stenting were enrolled. All patients were mobilized at 4 hours and assessed at 10 hours postprocedure as to their suitability for hospital discharge. The first 50 patients remained in hospital overnight. The next 25 patients followed the same procedures but were discharged at 10 hours. The subjects were followed up at 48 hours and 30 days. Hemostasis was achieved in all patients following sheath removal and deployment of the Angio-Seal device. Twenty patients (27%) had minor groin oozing and two developed small hematoma. There were no major bleeding complications, pseudoaneurysm, vascular surgery, or groin infection. Groin oozing resulted in the delay of ambulation for 13 subjects but discharge was not delayed in any patient. All patients were reported to be suitable for hospital discharge at 10 hours postprocedure. There were no further complications at 30 days. The present study demonstrated that early mobilization and same-day discharge after coronary stenting using the Angio-Seal device is feasible in selected patients. Further studies are needed to determine the patient selection criteria and the potential cost-saving implications of this strategy.  相似文献   
1000.
STUDY OBJECTIVE: To determine the interobserver agreement between cardiologists and emergency physicians in the ECG diagnosis of acute myocardial infarction (AMI) in patients with left bundle branch block (LBBB) using the ECG algorithm previously described by Sgarbossa et al. METHODS: Using the Sgarbossa ECG algorithm, 4 cardiologists and 4 emergency physicians independently interpreted a test set of 224 ECGs with LBBB, of which 100 ECGs were from patients with an evolving AMI. A subset of 25 ECGs was reinterpreted by each reader to test intraobserver agreement for AMI as well as interobserver agreement for the degree of ST-segment deviation. Agreement rates for AMI were estimated using the kappa statistic. In addition, the sensitivity and specificity for diagnosing AMI were determined for each reader, using the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO I) enzyme criteria for AMI as the gold standard. The study was conducted at 3 university-affiliated medical centers. The test set contained ECGs from 100 patients enrolled in the GUSTO I trial with LBBB on their initial ECG and an evolving AMI confirmed by serum cardiac enzyme changes, and 124 control patients from the Duke Databank for Cardiovascular Disease who had stable, angiographically documented coronary artery disease and LBBB. RESULTS: There was excellent interobserver agreement (kappa=0.81, 95% confidence interval [CI] 0.80 to 0.83) between cardiologists and emergency physicians for diagnosing AMI. Intraobserver agreement kappa values for AMI diagnosis by cardiologists and emergency physicians were 0.81 (95% CI 0.67 to 0.94) and 0.71 (95% CI 0.54 to 0.89). The median sensitivity for diagnosing AMI by cardiologists and emergency physicians was 73% (range 66% to 80%) versus 67% (range 61% to 75%); median specificity was 98% (range 97% to 99%) versus 99% (range 98% to 99%). Spearman rank correlation coefficients for the degree of ST-segment deviation in all 12 leads was 0.86 (95% CI 0.85 to 0.87) among all readers. CONCLUSION: There is excellent interobserver agreement between cardiologists and emergency physicians for diagnosing AMI when applying the Sgarbossa ECG algorithm to patients with LBBB. Emergency physicians should be able to reliably use this algorithm when evaluating patients.  相似文献   
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