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排序方式: 共有928条查询结果,搜索用时 15 毫秒
31.
Cavazzana I Franceschini F Belfiore N Quinzanini M Caporali R Calzavara-Pinton P Bettoni L Brucato A Cattaneo R Montecucco C 《Clinical and experimental rheumatology》2001,19(4):403-409
OBJECTIVE: To evaluate the clinical and serologic profile, the rate of progression to well defined CTD and the possible predictors of disease evolution in patients affected by UCTD with antibodies anti-RoISSA. METHODS: 148 patients diagnosed as UCTD were retrospectively evaluated. Antibodies to SSA/Ro were determined by counter-immunoelectrophoresis and ELISA. RESULTS: Thirty-six patients (24.3%) developed a well-defined CTD after a mean follow-up of 4.5 years. Most patients developed primary Sj?gren's syndrome (SS) (50%) or systemic lupus erythematosus (SLE) (30.5%). Leukopenia and xerophthalmia developed more frequently in the group of patients evolving to defined CTDs (p < 0.0032 and p < 0.0063). Leukopenia independently predicted the evolution in CTD by multivariate regression analysis (p < 0.019). Anti-dsDNA predicted the evolution in SLE (p < 0.0207), while the presence of additional anti-ENA specificity to anti-Ro/SSA was not associated with the outcome. CONCLUSION: 24.3% of patients with UCTD and antibodies to Ro/SSA can progress in a relatively short period of time to well-defined CTDs. The development of primary SS could be predicted by xerophthalmia and SLE by the appearance of anti-dsDNA antibodies. 相似文献
32.
Jones CD Loehr L Franceschini N Rosamond WD Chang PP Shahar E Couper DJ Rose KM 《Hypertension》2012,59(5):913-918
Heart failure causes significant morbidity and mortality. Distinguishing risk factors for incident heart failure can help identify at-risk individuals. Orthostatic hypotension may be a risk factor for incident heart failure; however, this association has not been fully explored, especially in nonwhite populations. The Atherosclerosis Risk in Communities Study included 12363 adults free of prevalent heart failure with baseline orthostatic measurements. Orthostatic hypotension was defined as a decrease of systolic blood pressure ≥20 mmHg or diastolic blood pressure ≥10 mmHg with position change from supine to standing. Incident heart failure was identified from hospitalization or death certificate disease codes. Over 17.5 years of follow-up, orthostatic hypotension was associated with incident heart failure with multivariable adjustment (hazard ratio: 1.54 [95% CI: 1.30-1.82]). This association was similar across race and sex groups. A stronger association was identified in younger individuals ≤55 years old (hazard ratio: 1.90 [95% CI: 1.41-2.55]) than in older individuals >55 years old (hazard ratio: 1.37 [95% CI: 1.12-1.69]; interaction P=0.034). The association between orthostatic hypotension and incident heart failure persisted with exclusion of those with diabetes mellitus, coronary heart disease, and those on antihypertensives or psychiatric or Parkinson disease medications. However, exclusion of those with hypertension somewhat attenuated the association (hazard ratio: 1.34 [95% CI: 1.00-1.80]). We identified orthostatic hypotension as a predictor of incident heart failure among middle-aged individuals, particularly those 45 to 55 years of age. This association may be partially mediated through hypertension. Orthostatic measures may enhance risk stratification for future heart failure development. 相似文献
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34.
Rossi A Franceschini L Fusaro M Cicoira M Eleas AA Golia G Bonapace S Santini F Sangiorgi G Zardini P Vassanelli C 《International journal of cardiology》2006,111(2):263-266
The instability of atherosclerotic plaque is partly determined by local factors, but systemic factors such as infection, inflammation, autoimmunity or genes might also be important. We aimed to analyze whether patients with acute myocardial infarction (AMI) might have a higher proportion of unstable plaques in the carotid arteries compared with patients who had had no acute coronary events. METHODS: Sixty-nine consecutive patients with AMI (Group 1) and 95 patients without acute coronary events (Group 2) had carotid artery duplex ultrasounds. Carotid atherosclerosis was quantified by number of plaques in the two carotid arteries, intimal media thickening and degree of maximal stenosis. According to their morphology, plaques were divided into stable (fibrocalcific) and unstable (soft and/or not homogeneous). RESULTS: The two groups did not differ as regards age (66+/-8 vs. 68+/-19; p=0.3), female sex (13% vs. 21%; p=0.3), mean number of carotid plaques (2.8+/-1 vs. 2.5+/-2; p=0.2), degree of stenosis (59+/-2% vs. 36+/-1%; p=0.2) or intimal media thickening (1.04+/-0.2 vs. 1.06+/-0.2; p=0.8). However, Group 1 pts more frequently had unstable carotid plaques compared with Group 2 (43% vs. 15%; p=0.004), and had a greater number of unstable carotid plaques (0.51+/-0.6 vs. 0.16+/-0.4: p<0.0001) and a higher ratio of unstable to stable plaque (19% vs. 8%; p=0.005). In the overall population, logistic regression analysis showed that after adjustment for degree of maximal stenosis, the presence of coronary artery event (AMI pts) predicted the presence of unstable carotid plaque (OR: 4.3 95% CI: 2.0-9.2; p=0.0002). CONCLUSION: Patients with unstable coronary artery disease expressed clinically as AMI, frequently had unstable atherosclerotic plaques in other arterial sites such as carotid arteries. This finding supports the hypothesis that plaque instability might reflect a systemic process. 相似文献
35.
G. Amicosante B. Segatore M. Perilli A. Felici N. Franceschini 《Journal of chemotherapy (Florence, Italy)》2013,25(6):399-402
SummaryWe measured the kinetics of hydrolysis of various cephalosporins by the chromosomally-encoded β-lactamases of Citrobacter diversus ULA-27. Cefonicid, cefamandole, cefatrizine and cefoperazone were all hydrolyzed hut these antibiotics showed a different feature in their kinetic parameters. Moreover, cefoperazone was a non-competitive inhibitor of this type of enzyme. Cefotetan was stable to hydrolysis and behaved like a progressive inactivator. The ability of these enzymes to inactivate the reported antibiotics contributes largely to the resistance of the studied strain. We concluded that hydrolysis is the main mechanism of resistance of this strain to the new cephalosporins. 相似文献
36.
Image analysis quantification of substance P immunoreactivity in the trapezius muscle of patients with fibromyalgia and myofascial pain syndrome 总被引:3,自引:0,他引:3
De Stefano R Selvi E Villanova M Frati E Manganelli S Franceschini E Biasi G Marcolongo R 《The Journal of rheumatology》2000,27(12):2906-2910
OBJECTIVE: Substance P (SP), a neurotransmitter stored within the afferent nociceptive fibers, is likely to be involved in the pathogenesis of musculoskeletal pain. We investigated SP immunoreactive (SP-ir) nerve fibers in the upper trapezius of patients with fibromyalgia (FM) and myofascial pain syndrome (MPS) by immunochemistry. METHODS: Trapezius muscle obtained from tender points of 9 women with primary FM, from trigger points of 9 women with regional myofascial pain, and from 9 control women were immunostained with anti-SP sera. Quantitative evaluation was performed by computerized image analysis. RESULTS: No significant differences in the number of SP-ir areas were detected between groups (one way ANOVA: p = 0.2); in contrast, mean optical density (OD) of SP-ir showed a significant difference comparing the groups (one way ANOVA: p < 0.0001). Mean OD of the immunostaining for SP was statistically greater in trapezius muscle of patients with MPS (0.594 +/- 0.096) compared to specimens from patients with FM (0.436 +/- 0.140) (p < 0.05) and controls (0.314 +/- 0.105) (p < 0.05); mean OD of immunostaining for SP was greater in FM specimens than in controls (p < 0.05). CONCLUSION: Our results point to a peripheral hyperactivity of the peptidergic nervous system in FM as well as in MPS. These findings support the notion of pathogenetic involvement of the afferent nervous system in the development and perception of myofascial pain. 相似文献
37.
Calabresi L Rossoni G Gomaraschi M Sisto F Berti F Franceschini G 《Circulation research》2003,92(3):330-337
The incidence and severity of primary cardiac events are inversely related to the plasma concentration of high-density lipoproteins (HDLs). We investigated whether HDLs may exert a direct cardioprotection in buffer-perfused isolated rat hearts, which underwent a 20-minute low-flow ischemia followed by a 30-minute reperfusion. The administration of HDLs at physiological concentrations (0.5 and 1.0 mg/mL) during the 10 minutes immediately before ischemia rapidly and remarkably improved postischemic functional recovery and decreased creatine kinase release in the coronary effluent. Reconstituted HDLs containing apolipoprotein A-I (apoA-I) and phosphatidylcholine, but not lipid-free apoA-I or phosphatidylcholine liposomes, were also effective in protecting the heart from ischemia-reperfusion injury. HDLs at reperfusion were less effective than when given before ischemia. HDLs caused a dose-dependent reduction of ischemia-induced cardiac tumor necrosis factor-alpha (TNF-alpha) expression and content, which correlated with the improved functional recovery. A parallel increase of TNF-alpha release in the coronary effluent was observed, due to a direct binding of cardiac TNF-alpha to HDLs. Taken together, these findings argue for a cause-effect relationship between the HDL-mediated removal of TNF-alpha from the ischemic myocardium and the HDL-induced cardioprotection. Indeed, etanercept, a recombinant TNF-alpha-blocking protein, caused a dose-dependent improvement of postischemic functional recovery. HDLs also enhanced ischemia-induced prostaglandin release, which may contribute to the cardioprotective effect. A low plasma HDL level may expose the heart to excessive ischemia-reperfusion damage, and HDL-targeted therapies may be helpful to induce immediate or delayed myocardial protection from ischemia-reperfusion injury. 相似文献
38.
Fabbri F Henry ME Renshaw PF Nadgir S Ehrenberg BL Franceschini MA Fantini S 《Brain research》2003,992(2):193-204
Reductions in right prefrontal cerebral blood flow have been correlated with symptomatic improvement in depressed individuals receiving electroconvulsive therapy (ECT). Non-invasive near infrared spectroscopy has previously been shown to reliably measure changes in cerebral hemoglobin concentrations and oxygen saturation. In this study, we measured the concentration and oxygen saturation of hemoglobin on the right and left frontal brain regions of nine patients during right unilateral ECT. In all patients, we have found that the electrically induced seizure causes a stronger cerebral deoxygenation on the side ipsilateral to the electrical current (-21+/-5%) with respect to the contralateral side (-6+/-4%). On the brain side ipsilateral to the ECT electrical discharge, we have consistently observed a discharge-induced decrease in the total hemoglobin concentration, i.e. in the cerebral blood volume, by -7+/-3 microM, as opposed to an average increase by 6+/-3 microM on the contralateral side. The ipsilateral decrease in blood volume is assigned to a vascular constriction associated with the electrical discharge, as indicated by the observed decrease in cerebral oxy-hemoglobin concentration and minimal change in deoxy-hemoglobin concentration during the electrical discharge on the side of the discharge. These findings provide indications about the cerebral hemodynamic/metabolic mechanisms associated with ECT, and may lead to useful parameters to predict the individual clinical outcome of ECT. 相似文献
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