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排序方式: 共有4891条查询结果,搜索用时 15 毫秒
91.
A new coronary artery disease index of treadmill exercise electrocardiograms based on the step-up diagnostic method 总被引:5,自引:0,他引:5
Treadmill exercise electrocardiography (ECG) is one of the most common noninvasive methods for detecting ischemic heart disease. However, this method has problems due to false-positive and false-negative results in a significant number of patients. The aim of this study was to determine whether the diagnostic accuracy of treadmill exercise ECG for detecting significant coronary stenosis can be improved by employing a step-up diagnostic method using multiple diagnostic indicators. We studied 273 consecutive patients (mean age, 56 +/- 9 years; 190 men and 83 women) without a history of myocardial infarction who underwent treadmill exercise ECG and coronary angiography for ischemic chest pain. Of these, 146 patients had no significant coronary stenosis, 61 had single-vessel disease, 56 had multivessel disease, and 10 patients had left main truncus disease. A multivariate logistic regression analysis was used to select 3 treadmill exercise electrocardiographic parameters that were independent predictors of the presence or absence of significant coronary stenosis: exercise-induced maximum ST-segment depression, QT dispersion immediately after exercise, and Athens QRS score. Significant coronary stenosis was diagnosed with a sensitivity of 84% and a specificity of 90% when a step-up diagnostic method using these 3 indicators was employed. These results were better than those obtained for each indicator alone (exercise-induced maximum ST-segment depression: sensitivity, 66%, and specificity, 73%; QT dispersion immediately after exercise [> or =60 ms positive]: sensitivity, 76%, and specificity, 86%; and Athens QRS score [< or =5 mm positive]: sensitivity, 72%, and specificity, 72%). We conclude that this step-up diagnostic method, using multiple diagnostic indicators, is a clinically useful predictor of the presence or absence of significant coronary stenosis. 相似文献
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We investigated the effect of diesel exhaust particles (DEP) extracts on collagen-induced arthritis (CIA) in mice. For this study, a single DEP sample was consecutively extracted with hexane (HEX-DEP), benzene (BEN-DEP), dichloromethane (DIC-DEP), methanol (MET-DEP), and 1 u M ammonia (AMM-DEP) in that order. Residues unextracted with the last extraction solvent 1 u M ammonia (UNE-DEP) were also used for experiments. To induce CIA, mice were immunized with type II collagen (CII) and 21 days later given a booster injection. DEP, each DEP extract, and UNE-DEP were intranasally administered every two days over a period of 20 days, commencing on the day of immunization. The results showed that treatment of mice with DEP, DIC-DEP, and UNE-DEP augmented both the incidence and the severity of CIA. DEP and DIC-DEP increased production of anti-CII IgG, IgG2a, and IgG1 antibodies as well as secretion of IFN- n and IL-4. Treatment with UNE-DEP resulted in an increase in antigen-specific IgG, IgG2a, and IFN- n but neither IgG1 nor IL-4. AMM-DEP failed to affect CIA as well as production of IgG2a and IFN- n, although significant increases in anti-CII IgG1 and IL-4 were observed in the treatment group. HEX-DEP, BEN-DEP, and MET-DEP had no effects on CIA and production of antibodies and cytokines examined. Thus, DEP and DIC-DEP appear to contain compounds, which enhance both Th1 and Th2 responses, while UNE-DEP and AMM-DEP to contain chemicals, which augment Th1 and Th2 alone, respectively. Th1- but not Th2-modulating compounds from DEP, DIC-DEP, and UNE-DEP seem to influence CIA. 相似文献
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Yoshino Koichi Ito Koji Kuroda Masahiko Sugihara Naoki 《Clinical oral investigations》2020,24(4):1543-1549
Clinical Oral Investigations - The purpose of this study was to clinically investigate double-crown-retained removable partial dentures (DRPDs) and abutment teeth at dental clinics. Only cases with... 相似文献
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Fluvastatin increases LDL particle size and reduces oxidative stress in patients with hyperlipidemia
Yoshino G Hirano T Kazumi T Takemoto M Ohashi N 《Journal of atherosclerosis and thrombosis》2003,10(6):343-347
The effects of fluvastatin on levels of urinary 8-iso-prostaglandin F2alpha (iPF2alphaIII), a marker of oxidative stress, and low-density lipoprotein (LDL) particle size in serum were investigated in patients with hypercholesterolemia. After 6 months of fluvastatin therapy, levels of urinary iPF2alphaIII decreased from 1720.1 +/- 392.0 to 539.6 +/- 75.5 pg/mg (p < 0.01), and LDL particle size increased from 24.3 +/- 0.3 to 26.5 +/- 0.2 nm (p < 0.001). These changes from the treatment of fluvastatin were not correlated with those of the serum LDL cholesterol (LDL-C) levels. The results imply that fluvastatin, with its unique antioxidant property among statins, reduces oxidative stress and increases LDL particle size simultaneously in hyperlipidemic patients. 相似文献