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81.
Pimobendan, a new oral cardiotonic and vasodilator agent, increases myocardial contractile force through specific inhibition of phosphodiesterase type III and increased calcium sensitivity of the myocardial contractile elements. The effects of pimobendan on left ventricular performance and maximal exercise capacity were studied in a multicenter, randomized, double-blind, placebo-controlled trial involving 52 patients with severe congestive heart failure despite diuretics, digoxin, and angiotensin-converting enzyme inhibitors. The acute hemodynamic evaluation included three single doses of 2.5, 5.0, and 10.0 mg of oral pimobendan, which was subsequently administered at a daily dose of 5 or 10 mg for 4 weeks. Acute administration of pimobendan significantly increased the resting cardiac index and lowered pulmonary capillary wedge pressure in a dose-dependent manner, whereas heart rate and systemic arterial pressure were not substantially altered. Patients receiving pimobendan, 5 and 10 mg daily, had a significantly greater increase in maximal exercise duration than those receiving placebo, that is, 144 +/- 30 and 124 +/- 33 seconds versus 58 +/- 25 seconds (p = 0.05). Peak oxygen uptake increased by 1.7 +/- 0.8 and 2.2 +/- 1.3 ml/kg/min in patients receiving pimobendan at a daily dose of 5 and 10 mg, respectively, whereas it decreased by 0.1 +/- 0.6 ml/kg/min in patients receiving placebo (p = 0.06). Thus pimobendan acutely improves resting left ventricular performance and chronically increases exercise duration and peak oxygen uptake in patients with severe congestive heart failure concomitantly treated with digoxin, diuretics, and angiotensin-converting enzyme inhibitors.  相似文献   
82.
BACKGROUND AND AIM OF THE STUDY: An alternative to avoid redo sternotomy in patients with patent left internal mammary artery-left anterior descending coronary artery (LIMA-LAD) grafts undergoing mitral valve surgery is right thoracotomy with moderate-deep hypothermia (approximately 20 degrees C) and fibrillatory arrest without aortic cross-clamping. Few reports exist which directly compare re-sternotomy and right thoracotomy. METHODS: Between July 1992 and February 2000, 47 patients (39 males, eight females; median age 66 years; range: 41-83 years; 41 in NYHA class III or IV) with patent LIMA-LAD grafts underwent mitral valve surgery. Thirty-seven patients were approached through a right thoracotomy with moderate-deep hypothermia (median 20 degrees C) and fibrillatory arrest (right thoracotomy group), and 10 were approached through a re-sternotomy, with aortic cross-clamping and cardioplegic arrest. The median ejection fraction was 42% (range: 20-71%). Univariate analysis was used to determine predictors of outcome, as well as to evaluate differences in characteristics between groups. RESULTS: Operative mortality (OM) and perioperative myocardial infarction for the entire cohort was 11% and 10%, respectively, and there were no inter-group differences. No preoperative characteristics were associated with OM. Two LIMA-LAD graft injuries occurred in the re-sternotomy group compared with none in the right thoracotomy group (20% versus 0%, p = 0.04). Transfusion requirements were also greater in the redo sternotomy group (median 7 versus 2 packed red blood cell units, p = 0.04). CONCLUSION: Right thoracotomy with moderate-deep hypothermia and fibrillatory arrest is the preferred approach for reoperative mitral valve surgery after coronary artery bypass grafting in the presence of patent LIMA-LAD grafts. These data suggest that this approach is associated with decreased incidence of LIMA-LAD graft injury, as well as reduced transfusion requirements.  相似文献   
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To compare the hemodynamic results of different anuloplasty techniques of primary valve repair for mitral regurgitation, 122 patients were prospectively studied with Doppler echocardiograms 5 to 10 days after operation. Seventy-seven patients had mitral valve prolapse, 27 had coronary artery disease, 13 patients had rheumatic mitral valve lesions and 5 patients had infective endocarditis. Forty-eight patients received the flexible Duran ring, 46 received the more rigid Carpentier ring and 28 patients received no ring. Doppler echocardiography demonstrated a significant decrease in mitral valve area estimated by the pressure half-time method in patients who received either a Carpentier (2.6 +/- 0.8 cm2) or Duran ring (2.8 +/- 0.8 cm2) when compared with patients who received no ring (3.2 +/- 0.7 cm2) (p = 0.01). No significant differences were observed for peak transmitral diastolic velocity, peak transmitral diastolic gradient, or the grade of mitral regurgitation by color flow Doppler mapping between patients with and without rings. The etiology of mitral disease and concomitant surgical procedures accompanying mitral valve repair did not significantly influence mitral valve area, peak velocity or peak gradient. These data suggest that Carpentier and Duran rings decrease the hemodynamic mitral valve area; however, the decrease in valve area is small and not associated with a clinically important increase in transvalvular gradient.  相似文献   
85.
STUDY OBJECTIVE: To evaluate the efficacy and toxicity of a 62-dose, four-drug, 6-month, and directly observed regimen for treatment of pulmonary and extrapulmonary tuberculosis. DESIGN: An open, nonblinded clinical trial, with intended follow-up of patients for 36 months after the completion of therapy. SETTING: A metropolitan tuberculosis clinic in a public health department. PATIENTS: From March 1981 through April 1989, we enrolled 160 patients with suspected or known tuberculosis; 35 of these patients were excluded from the analysis. INTERVENTIONS: Isoniazid, rifampin, pyrazinamide, and streptomycin were administered daily for 2 weeks; these drugs were then given in higher doses twice weekly for 6 weeks, followed by isoniazid and rifampin twice weekly for 6 weeks, followed by isoniazid and rifampin twice weekly for 18 weeks. A total of 62 doses were administered, and all therapy was directly observed by a nurse or an outreach worker. MEASUREMENTS AND MAIN RESULTS: Of the 125 evaluable patients, 101 (81%) had pulmonary tuberculosis, 7 (6%) had both pulmonary and extrapulmonary involvement, and 17 (13%) had extrapulmonary disease only. Seventy-one (57%) patients had a history of recent alcoholism. There were two relapses (1.6% +/- 2.2%), occurring 6 and 56 months after the completion of therapy. The time at which sputum samples became culture negative in pulmonary patients ranged from 1 to 19 weeks (median, 4.6 weeks); 40% +/- 9.6% of patients were culture-negative after 4 weeks of therapy, 75% +/- 8.5% after 8 weeks, 94% +/- 4.7% after 12 weeks, 97% +/- 3.3% after 16 weeks, and 100% after 20 weeks. Adverse drug reactions included hyperuricemia (greater than 178 mumol/L [3 mg/dL] above normal) secondary to pyrazinamide in 80 patients (64%), twofold or greater elevations of aspartate aminotransferase in 21 patients (17%), 1.5-fold or greater elevations of alkaline phosphatase in 33 patients (27%), cutaneous abnormalities in 8 patients (6%), nausea in five patients (4%), and dizziness in 1 patient (1%). CONCLUSIONS: This 62-dose, largely twice-weekly tuberculosis treatment regimen is efficacious and relatively nontoxic and is especially useful for patients in whom directly observed therapy is indicated.  相似文献   
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Summary Although intestinal antiseptics do have relative dangers, and although only 7 of 35 different intestinal antiseptics can be recommended for general use, the value of antibiotics in surgery of the colon has been experimentally demonstrated in protection of a colon anastomosis.Based upon clinical studies of 559 patients prepared for surgery with kanamycin, 79 who received postoperative intraluminal kanamycin, and 360 who received intraperitoneal antibiotic therapy at operation for some form of peritonitis, judicious use of antibiotics in conjunction with colon surgery is highly recommended.Presented at a postgraduate course, Advances in Gastroenterology—Enterocolonic Disease and Dysfunction (Oct. 22–24, 1964), sponsored by Louisiana State University School of Medicine, New Orleans, La.Supported in part by Grants Al-01600 and Al-00524 from the National Institute of Allergy and Infectious Diseases, National Institutes of Health, U. S. Public Health Service.  相似文献   
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Non-alcoholic fatty liver disease (NAFLD) is a frequent accompaniment of obesity and insulin resistance. With the prevalence approaching 85% in obese populations, new therapeutic approaches to manage NAFLD are warranted. A systematic search of the literature was conducted for studies pertaining to the effect of omega-3 polyunsaturated fatty acid (PUFA) supplementation on NAFLD in humans. Primary outcome measures were liver fat and liver function tests: alanine aminotransferase (ALT) and aspartate aminotransferase [1]. Data were pooled and meta-analyses conducted using a random effects model. Nine eligible studies, involving 355 individuals given either omega-3 PUFA or control treatment were included. Beneficial changes in liver fat favoured PUFA treatment (effect size=-0.97, 95% CI: -0.58 to -1.35, p<0.001). A benefit of PUFA vs. control was also observed for AST (effect size=-0.97, 95% CI: -0.13 to -1.82, p=0.02). There was a trend towards favouring PUFA treatment on ALT but this was not significant (effect size=-0.56, 95% CI: -1.16 to 0.03, p=0.06). Sub-analyses of only randomised control trials (RCTs) showed a significant benefit for PUFA vs. control on liver fat (effect size=-0.96, 95% CI: -0.43 to -1.48, p<0.001), but not for ALT (p=0.74) or AST (p=0.28). There was significant heterogeneity between studies. The pooled data suggest that omega-3 PUFA supplementation may decrease liver fat, however, the optimal dose is currently not known. Well designed RCTs which quantify the magnitude of effect of omega-3 PUFA supplementation on liver fat are needed.  相似文献   
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