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21.
This study investigated the association of blood pressure with blood oxidative stress-related parameters in normotensive and hypertensive subjects. A cross-sectional design was applied to 31 hypertensive patients and 35 healthy normotensive subjects. All subjects were men between the ages of 35 and 60 years. Exclusion criteria were obesity, dyslipidemia, diabetes mellitus, smoking and current use of any medication. All patients underwent 24-h ambulatory blood pressure monitoring and sampling of blood and urine. Antioxidant enzymes activity, reduced/oxidized glutathione ratio (GSH/GSSG), and lipid peroxidation (malondialdehyde) were determined in erythrocytes. Parameters measured in the plasma of test subjects were plasma antioxidant status, lipid peroxidation (8-isoprostane), plasma vitamin C and E, and the blood pressure modulators renin, aldosterone, endothelin-1 and homocysteine. Daytime systolic and diastolic blood pressures of hypertensives were negatively correlated with plasma antioxidant capacity (r=-0.46, p<0.009 and r=-0.48, p<0.007), plasma vitamin C levels (r=-0.53, p<0.003 and r=-0.44, p<0.02), erythrocyte activity of antioxidant enzymes, and erythrocyte GSH/GSSG ratio, with hypertensives showing higher levels of oxidative stress. Blood pressures showed a positive correlation with both plasma and urine 8-isoprostane. Neither plasma vitamin E nor the assessed blood pressure modulator levels showed significant differences between the groups or correlation with blood pressures. These findings demonstrate a strong association between blood pressure and some oxidative stress-related parameters and suggest a possible role of oxidative stress in the pathophysiology of essential hypertension.  相似文献   
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To determine the therapeutic activity on regional myocardial function of nifedipine intravenous administration (0.16 mg/kg) during short term myocardial induced ischemia, we used 6 mongrel dogs anesthetized and intubated those who we have implanted 3 pairs of ultrasonic crystals in the subendocardial layer. Utilizing an open chest canine model we performed total 1 minute and partial 2 minutes 30 seconds alternative obstructions, controlled with electromagnetic flowmeters in the anterior descending (AD) and circumflex (Cx) coronary arteries before and after drug administration. During the 70-80% obstructions we have shown a significant improvement in segment shortening, reduced by ischemia, in the ischemic and peri-ischemic zone. The ischemic markers, per cent increment of end diastolic length (% IEDL) and per cent increment of end systolic length (% IESL), have shown significant improvement during partial obstructions in the ischemic and peri-ischemic zone. After total obstructions the improvement on regional myocardial function is less marked and limited to ischemic zone.  相似文献   
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We study 40 patients, 55 +/- 7 years old with acute myocardial infarction treated early by thrombolytic therapy (20 STK and 20 rt-PA). All patients were angiographically studied in the following conditions: 1) baseline, before initiating therapy. 2) Three hours after treatment. 3) Twenty four hours later. 4) Before discharge. The infarct related artery was patent 24 hours after treatment in 31 patients (78%); five of them were patent before treatment, and we observed an early reperfusion in 20 patients (57%) and late reperfusion in 6 patients (17%). The number of patients with angiographic evidence of intraluminal thrombus decreased progressively through conditions while the grade TIMI of coronary perfusion increased in the absence of reocclusion. Final regional wall motion of infarct related myocardial zones and their degree of recovery were significantly higher in recanalized patients, as compared with non-reperfused patients. Similarly, left ventricular functional recovery was higher in patients with antegrade of collateral flow to the infarct area, as compared with totally occluded patients.  相似文献   
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Summary Pyomyositis is an acute bacterial infection of striated muscle. It is common in the tropics, but rarely reported in temperate climates. We present two cases in patients with the acquired immune deficiency syndrome (AIDS), one an active homosexual, and one an intravenous drug user. A brief review of the clinical findings and diagnostic procedures is included. We conclude that pyomyositis should be included in the list of locations of pyogenic infections that can occur in AIDS patients.
Spontane Pyomyositis und AIDS: ein seltenes Zusammentreffen
Zusammenfassung Die Pyomyositis ist eine akute bakterielle Infektion der quergestreiften Muskulatur. Im Gegensatz zu den Tropen, wo sie häufig auftritt, wird die Pyomyositis in gemäßigten Klimazonen nur selten beobachtet. Wir stellen zwei Patienten mit Pyomyositis und AIDS vor: der eine Patient ist Homosexueller, der andere intravenös drogenabhängig. Klinische Befunde und diagnostisches Vorgehen werden kurz dargestellt. Nach unserer Meinung sollte die Pyomyositis in die Liste pyogener Infektionslokalisationen bei AIDS-Patienten eingereiht werden.
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Moderate increases in ``classical' biochemical markers of bone turnover have been described only in some patients with Camurati–Engelmann disease. However, the determination of the following ``new' markers has not been previously performed: serum osteocalcin (BGP), bone alkaline phosphatase (BAP), carboxyterminal propeptide of type I procollagen (PICP), aminoterminal propeptide of type I procollagen (PINP), tartrate-resistant acid phosphatase (TRAP), telopeptide carboxyterminal of type I collagen (ICTP), urinary pyridinoline (PYR), crosslinked N-telopeptides of type I collagen (NTX), and Crosslaps (CL). Such a determination may improve the evaluation of the disease activity. To evaluate the usefulness of biochemical markers of bone turnover reflecting Camurati–Engelmann disease activity we measured the levels of all these markers in four affected patients. The results were compared with bone scintigraphic indices of disease activity. Except for PICP and TRAP, bone formation and resorption markers were abnormal in all patients and were related to bone scan indices of disease activity. Among the markers of bone formation PINP, BAP, and BGP showed the highest values, whereas NTX and CL were the most sensitive markers of bone resorption. These results suggest that the determination of NTX or CL, and PINP or either BAP and BGP, associated with bone scan evaluation, provides the best assessment of Camurati–Engelmann disease activity. Received: 14 June 1996 / Accepted: 31 December 1996  相似文献   
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