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141.
CI Stefanadis CG Stratos SG Lambrou VK Bahl DV Cokkinos VA Voudris SG Foussas CP Tsioufis PK Toutouzas 《Canadian Metallurgical Quarterly》1998,32(4):1009-1016
OBJECTIVES: Our aim was to present the immediate and intermediate long-term results of the application of retrograde nontransseptal balloon mitral valvuloplasty (RNBMV) in four cooperating centers from Greece and India. BACKGROUND: RNBMV is a purely transarterial method of balloon valvuloplasty, developed with the aim to avoid complications associated with transseptal catheterization. Only single-center experience with RNBMV has been previously reported. METHODS: The procedure was attempted in 441 patients with symptomatic mitral stenosis (320 women, 121 men, mean age [+/-SD] 44+/-11 years, mean echocardiographic score [+/-SD] 7.7+/-2.0) from 1988 to 1996. Three hundred eighty-five patients with successful immediate outcome were followed clinically for a mean [+/-SD] of 3.5+/-1.9 (range, 0.5-9.1) years. RESULTS: A technically successful procedure was achieved in 388 (88%) cases. The echocardiographic score (p < 0.001), male gender (p=0.005), preprocedural mitral regurgitation (p=0.007) and previous surgical commissurotomy (p=0.029) were unfavorable predictors of immediate outcome. Complications included death (0.2%), severe mitral regurgitation (3.4%) and injury of the femoral artery (1.1%). Event-free (freedom from cardiac death, mitral valve surgery, repeat valvuloplasty and NYHA class > II symptoms) survival rates (+/-SEM) were 100%, 96.9+/-0.9%, 89.8+/-1.9% and 75.5+/-5.5% at 1, 2, 4 and 9 years, respectively. The echocardiographic score (p < 0.001), NYHA class (p=0.008) and postprocedural mitral valve area (p=0.009) were significant independent predictors of intermediate long-term outcome. CONCLUSIONS: Multicenter experience indicates that RNBMV is a safe and effective technique for the treatment of symptomatic mitral stenosis. As with the transseptal approach, patients with favorable mitral valve anatomy derive the greatest immediate and intermediate long-term benefit from this procedure. 相似文献
142.
Home-made protective eyeshields are described, for use during certain types of skull radiography. Measurements made during the examination of patients and with a phantom skull indicate that a ten-fold reduction in radiation dose may be achieved through their use during certain diagnostic procedures. 相似文献
143.
We recently demonstrated that net fluid uptake occurs in the capillary system of the inner medulla. To define the site of fluid uptake, the concentration of protein was determined in plasma from descending vasa recta at the base and tip of the exposed papilla in Munich-Wister rats. The vasa recta plasma-to-arterial plasma protein concentration ratio (VR/P) was 1.43 +/- 0.09 at the base and 1.66 +/- 0.09 at the tip. These results, which indicate fluid loss from the descending vasa recta, are difficult to explain on the basic of hydraulic and oncotic forces alone. The osmolality of the contents of descending vasa recta increased between base and tip (delta = 72 +/- 30 mosmol/kg H2O). If the increase in osmolality of plasma in descending vasa recta lags behind that of the adjacent medullary interstitium, a transcapillary osmotic driving force exists favoring water loss from descending vessels. It is concluded that fluid uptake by the inner medullary circulation occurs beyond descending vasa recta in interconnecting capillaries or ascending vasa recta. In our view the most likely interpretation of these results is that fluid movement across vasa recta in the inner medulla is influenced by three forces: those owing to transcapillary differences in osmotic, oncotic, and hydraulic pressures. 相似文献
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Seven anorexia nervosa (A.N.) patients had reduced urinary excretion values of tetrahydrocortisone (THE), androsterone (A) and 5alpha-tetrahydrocortisol (5alpha-THF). THE to tetrahydrocortisol (THF), A to aetiocholanolone (Ae) and 5alpha-THF to THF ratios were all significantly reduced. Six A.N. patients had oral metyrapone tests with quantitatively normal but delayed urinary 3alpha,17alpha,21-trihydroxy-5beta-pregnan-20-one (THS) response. The steroid determinations were done by capillary gaschromatography, which proves to be of value in the study of the above mentioned metabolic abnormalities. 相似文献
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Prediction charts used in the management of patients suffering from rhesus haemolytic disease are presented and the accuracy investigated for two methods of amniotic fluid analysis. In 468 samples from 141 patients there were 7-9 per cent errors of prediction when both methods were used together but in only four cases (2-8 per cent) was the error thought to have possibly contributed to wrong management. 相似文献