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We report here the antiproteolytic and antihemorrhagic properties of triterpenoid saponin inhibitors, named macrolobin-A and B, from Pentaclethra macroloba, against Bothrops snake venoms. The inhibitors were able to neutralize the hemorrhagic, fibrin(ogen)olytic, and proteolytic activities of class P-I and P-III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. Clotting and fibrinogenolytic activities induced by snake venoms and isolated thrombin-like enzymes were partially inhibited. Furthermore, the potential use of these inhibitors to complement antivenom therapy as an alternative treatment and/or used as molecular models for development of new therapeutical agents in the treatment of snake bite envenomations needs to be evaluated in future studies.  相似文献   
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This case report demonstrates how extracting a maxillary deciduous canine affects the eruption path of a labially displaced ectopically erupting permanent canine. A long-term follow-up is presented, and the biologic mechanisms are discussed.  相似文献   
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Atrial electrical remodeling plays a part in recurrence of atrial fibrillation (AF). It has been related to an increase in heterogeneity of atrial refractoriness that facilitates the occurrence of multiple reentry wavelets and vulnerability to AF. AIM: To examine the relationship between dispersion of atrial refractoriness (Disp_A) and vulnerability to AF induction (A_Vuln) in patients with clinical paroxysmal AF (PAF). METHODS: Thirty-six patients (22 male; age 55+/-13 years) with > or =1 year of history of PAF (no underlying structural heart disease--n=20, systemic hypertension--n=14, mitral valve prolapse--n=1, surgically corrected pulmonary stenosis--n=1), underwent electrophysiological study (EPS) while off medication. The atrial effective refractory period (AERP) was assessed at five different sites--high (HRA) and low (LRA) lateral right atrium, high interatrial septum (IAS), proximal (pCS) and distal (dCS) coronary sinus--during a cycle length of 600 ms. AERP was taken as the longest S1-S2 interval that failed to initiate a propagation response. Disp_A was calculated as the difference between the longest and shortest AERP. A_Vuln was defined as the ability to induce AF with 1-2 extrastimuli or with incremental atrial pacing (600-300 ms) from the HRA or dCS. The EPS included analysis of focal electrical activity based on the presence of supraventricular ectopic beats (spontaneous or with provocative maneuvers). The patients were divided into group A--AF inducible (n=25) and group B--AF not inducible (n=11). Disp_A was analyzed to determine any association with A_Vuln. Disp_A and A_Vuln were also examined in those patients with documented repetitive focal activity. Logistic regression was used to determine any association of the following variables with A_Vuln: age, systemic hypertension, left ventricular hypertrophy, left atrial size, left ventricular function, duration of PAF, documented atrial flutter/tachycardia and Disp_A. RESULTS: There were no significant differences between the groups with regard to clinical characteristics and echocardiographic data. AF was inducible in 71% of the patients and noninducible in 29%. Group A had greater Disp_A compared to group B (105+/-78 ms vs. 49+/-20 ms; p=0.01). Disp_A was >40 ms in 50% of the patients without A_Vuln and in 91% of those with A_Vuln (p=0.05). Focal activity was demonstrated in 14 cases (39%), 57% of them with A_Vuln. Disp_A was 56+/-23 ms in this group and 92+/-78 ms in the others (p=0.07). Using logistic regression, the only predictor of A_Vuln was Disp_A (p=0.05). CONCLUSION: In patients with paroxysmal AF, Disp_A is a major determinant of A_Vuln. Nevertheless, the degree of nonuniformity of AERP appears to be less important as an electrophysiological substrate for AF due to focal activation.  相似文献   
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A 28-month-old boy, weighing 11 kg, with severe dilated cardiomyopathy, was transplanted on December 1995. Hypertension and supraventricular tachycardia were detected in the immediate post-operative period, with favorable outcome. After 5 months of clinically asymptomatic follow-up, a dilation in the ascending aorta was observed on routine echocardiogram. Nuclear magnetic resonance imaging (NMRI) confirmed an ascending aortic aneurysm, with a diameter of 38 mm. An operation was performed, a bovine pericardium patch was sutured with reconstruction of the aortic wall, excluding the aneurysm. Good recovery was obtained and the child was discharged on Day 7 postoperatively. A post-operative echocardiogram showed absence of the aortic aneurysm and good surgical results. Another NMRI was done 5 months later, showing an intact ascending aorta. After 64 months, the patients clinical condition was confirmed as normal by echocardiogram. Surgical treatment was successful and the positive results have been maintained.  相似文献   
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Left ventricular geometry is distorted after anterior infarction caused by occlusion of a wrap around left anterior descending artery. Loss of the apex creates a spherical left ventricular (LV) chamber, whose rebuilding requires reconstruction techniques that exclude the non-functional inferior wall. The described technique of tailoring the apex defines a way to create an oblique elliptical rim for subsequent patch placement to complete the restoration procedure. This method of ventricular rebuilding differs from methods that follow the inferior wall scar, which result in a restoration procedure that leaves a spherical or box-like apical region.  相似文献   
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Renal dysfunction after myocardial revascularization.   总被引:5,自引:0,他引:5  
OBJECTIVES: In this study, we evaluate the incidence of and analyse the pre and intraoperative risk factors for the development of postoperative renal dysfunction (PRD), and the impact of such an event on perioperative mortality and on hospital length of stay. In addition, we sought to investigate the influence of a mildly increased serum creatinine (1.3-2.0 mg/dl) on perioperative mortality and morbidity. METHODS: The study included 2445 consecutive patients who had no pre-existing renal disease (creatinine or=2.1 mg/dl with a preoperative-to-postoperative increase >or=0.9 mg/dl. Univariate and multivariate analyses were performed where appropriate. RESULTS: Global 30-day mortality was 0.7%. The incidence of PRD was 5.6% (136 patients). Mortality for patients who experienced PRD was 8.8 vs. 0.1% for patients who did not (P<0.001). PRD increased the length of hospital stay by 3.4 days (7.6 vs. 11.0 days; P<0.001), and patients who needed haemodialysis (11%) had a perioperative mortality of 33.3% and a mean hospital length of stay of 16 days. Multivariable logistic regression identified the following variables as independent predictors of PRD: age (P=0.017; odds ratio (OR) 1.3 per 10 years), angina class III/IV (P=0.003; OR 1.7); cardiopulmonary bypass time (P=0.007; OR 1.01 per minute); preoperative serum creatinine levels: group 1 (1.3-1.6 mg/dl (P<0.001; OR 5.5)) and group 2 (1.7-2.0 mg/dl (P<0.001; OR 14.2)). Finally, a mild elevation of the preoperative creatinine level (1.3-2.0 mg/dl) increased significantly the probability of perioperative mortality, low cardiac output, haemodialysis and prolonged hospital stay. CONCLUSIONS: Although the likelihood of PRD in patients without pre-existing renal dysfunction is relatively low, it dramatically increases mortality, morbidity and length of stay after CABG. Mildly elevated (>1.2 mg/dl) preoperative serum creatinine level significantly increases the perioperative mortality and morbidity.  相似文献   
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OBJECTIVE: Kidney transplantation restores renal filtration, although it does not achieve the function of 2 native kidneys, and with time it may involute back to chronic renal failure. We hypothesized that bioelectrical impedance analysis (BIA) might highlight differences for body compartments among kidney transplants (Tx) with different filtration rates. METHODS: Thirty transplantation patients (19 male, 11 female) were studied at 62.4+/-26.6 months postsurgery and were divided into 3 groups: good creatinine clearance (crCl, mL/min/1.73 m2; >65.0), borderline (35.0相似文献   
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