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1.
Controversy persists regarding whether the efficacy of closed instrumental mitral commissurotomy compares well enough with that of open commissurotomy to warrant its continued use. The purpose of this study was to compare the results of operation as determined by catheterization studies in 63 patients with pure, severe, and noncalcified mitral stenosis. The patients were randomly assigned to one of two groups: thirty-two patients were operated on by the closed technique (group I) and 31 by the open technique (group II). All patients underwent left-sided and right-sided catheterization before and 4 months after operation. Preoperatively the two groups were statistically similar with regard to major clinical data and hemodynamic findings. There were no deaths at operation or systemic embolism in the two groups. The prevalence of surgically induced mitral regurgitation was similar in the two groups (12.4% versus 12.9%). Pulmonary arterial pressure and arteriolar and total pulmonary vascular resistance decreased significantly in the two groups. Pulmonary capillary wedge pressure decreased from 23.3 +/- 8.5 to 15.8 +/- 7 mm Hg in group I (p less than 0.001) and from 23.7 +/- 6 to 14 +/- 5.8 mm Hg in group II (p less than 0.001). Cardiac index increased from 2.86 +/- 0.84 to 3.14 +/- 0.78 L/min/m2 in group I, but this increase did not reach statistical significance. In group II cardiac index increased from 2.89 +/- 0.6 to 3.6 +/- 0.6 L/min/m2 (p less than 0.005). The mean and end-diastolic transmitral pressure gradients decreased significantly in the two groups, but the decrease was statistically greater in the open mitral commissurotomy group (p less than 0.001). Mitral valve area increased from 0.82 +/- 0.18 to 1.4 +/- 0.40 cm2 in group I (p less than 0.01) and from 0.84 +/- 0.15 to 2.14 +/- 0.53 cm2 in group II (p less than 0.001). The mean increase in mitral valve area was 0.61 cm2 in group I and 1.34 cm2 in group II (p less than 0.001). At exercise, in patients with resting pulmonary capillary wedge pressures of 18 mm Hg or less, cardiac index increased by 36% in group I (23 patients) and 48% in group II (24 patients), because of a smaller mitral valve area in group I (1.61 +/- 0.39 cm2) than in group II (2.45 +/- 0.65 cm2). Thus open commissurotomy improved hemodynamic values to a greater extent than closed commissurotomy at both rest and exercise.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Genetic diversity was characterized in 20 isolates of Grapevine fanleaf virus (GFLV) recovered from naturally infected grapevine plants (Vitis vinifera) in the North of Tunisia. Viral RNAs were isolated by oligoprobe capture, and a 605 bp fragment containing a part of the viral coat protein gene was amplified by RT-PCR. Sequence variation among isolates was characterized by restriction fragment length polymorphism (RFLP) analysis and confirmed by sequencing. The GFLV infections are found as a complex mixture of closely related genomes. In further studies, RFLP analyses of virus isolates using AluI showed that GFLV populations in Tunisian vineyards consist of two restrictotypes corresponding to distinct sub-populations Sp1 and Sp2. The relative field distribution of these sub-populations showed that Sp2 was more abundant. Individual genomes were recovered by cloning the RT-PCR products. The sequences were found to vary from each other by as much as 11%. Cloning from mixed infections showed that Sp2 are also predominant.  相似文献   
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International Urology and Nephrology - Biomarkers for the diagnosis and monitoring treatment response of kidney cancer are urgently needed. Neutrophil gelatinase-associated lipocalin (NGAL) is a...  相似文献   
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Normal gestation is associated with a hyperdynamic adaptive state. The circulatory changes represent an additional burden on the cardiovascular system of women with rheumatic mitral stenosis (MS). Life-threatening complications can occur in pregnant women with severe MS. We successfully performed percutaneous balloon mitral valvotomy (PMV) in eight pregnant patients (mean age 28 +/- 6.9 years, range 21-38 years). Pregnancy mean age was 24.6 +/- 6.5 weeks. Five patients were in NYHA functional class III and three patients were in class IV. Emergency PMV seemed to be life saving to both mother and foetus in one case. All patients but one had pliable valves. PMV was achieved using the double balloon transseptal technique. To protect the foetus from radiation, the patient's pelvic-abdominal area was shielded and left ventriculography was not performed. The total mean time of PMV was 72 +/- 19 min and that of fluoroscopy was 16.6 +/- 7.8 min. Gorlin's mitral valve area increased from 0.83 +/- 0.15 to 2.4 +/- 0.34 cm2 and the cardiac index from 3.1 +/- 0.77 to 4.2 +/- 0.79 l.min-1.m-2. Left atrium pressure decreased from 29 +/- 10 to 14 +/- 5 mmHg and mitral valve gradient from 21 +/- 7 to 6 +/- 3 mmHg. There were no complications or residual MS. At a mean follow-up of 13.2 +/- 9.4 months, all patients were in NYHA class I and had a normal course of pregnancy. The eight women delivered healthy full-term babies. At 1-25 months post-partum follow-up, the eight infants had shown normal growth and development.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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