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61.
Acute effects of nifedipine in renal transplant recipients treated with cyclosporine or azathioprine
LB Hilbrands AJ Hoitsma HW van Hamersvelt JF Wetzels FT Huysmans RA Koene 《Canadian Metallurgical Quarterly》1994,24(5):838-845
Cyclosporine (CsA) impairs renal function, probably by preglomerular vasoconstriction. Vasodilating substances may therefore be of benefit to ameliorate CsA-induced renal dysfunction. We studied the acute effects on blood pressure and renal function of the dihydropyridine calcium antagonist nifedipine (10 mg orally) in 20 CsA-treated renal transplant patients. In addition, we compared the effects of nifedipine when given immediately before and 4 weeks after elective conversion from CsA to azathioprine. Compared with placebo (n = 14), administration of nifedipine led to a significant decrease in blood pressure and a strong natriuretic and diuretic response. Despite the reduction in blood pressure, glomerular filtration rate improved from 60 +/- 20 (mean +/- SD) to 69 +/- 24 mL/min/1.73 m2 (P < 0.001) and renal plasma flow (RPF) increased from 260 +/- 87 to 338 +/- 120 mL/min/1.73 m2 (P < 0.001). The combination of a decreased blood pressure with an increased RPF was reflected in a sharp decrease in renal vascular resistance (0.34 +/- 0.18 units v 0.23 +/- 0.10 units; P < 0.001). The conversion from CsA to azathioprine by itself led to significant increases in glomerular filtration rate (62 +/- 15 mL/min/1.73 m2 v 76 +/- 18 mL/min/1.73 m2; P < 0.05) and RPF (280 +/- 86 mL/min/1.73 m2 v 334 +/- 66 mL/min/1.73 m2; P < 0.05). During treatment with azathioprine an effect of nifedipine on glomerular filtration rate and RPF was no longer observed, although the natriuretic effect was similar on both occasions. The decrease in renal vascular resistance was larger during treatment with CsA than during treatment with azathioprine (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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The utility of the mixed carboxylic-sulfonic acid anhydride stearoyl p-toluenesulfonate as a powerful, mild acylating agent for lipid synthesis is shown by the synthesis of rac 1,2-distearoyl-3-iodopropane, lecithin and a spin-labeled choline derivative from the corresponding alcohols. The method constitutes a significant improvement of earlier acylating methods. 相似文献
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C Vallette JE Niboyet M Imbert-Martelet JF Roux 《Canadian Metallurgical Quarterly》1980,25(3):108-112
The application of acupuncture anesthesia in obstetrics is discussed and reviewed. Of 14 patients delivered by cesarean section under acupuncture, 8 (57%) felt no pain, and 6 did not go through the entire procedure without other supplementary anesthesia. The failure and success rates are reviewed. It is suggested that the technique be evaluated further because with acupuncture the fetus and mother are completely protected from the secondary effects of general regional anesthesia. 相似文献
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