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61.
LB Lane 《Canadian Metallurgical Quarterly》1993,18(2):366-368
The scaphoid test described by Watson has generally been accepted as the definitive test for scaphoid instability and uses pressure against the scaphoid tubercle as the wrist moves from ulnar to radial deviation for the evaluation. This article describes a stress test done with the wrist in neutral position, which actively provokes scaphoid instability. Variations in stability can be used to grade scaphoid laxity. 相似文献
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This study was designed to determine what effect physical training has on heart rate and stroke volume responses to exercise stress and to determine if exercise altered the distribution of uterine blood flow. Measurements were made in ten pregnant ewes at rest and immediately following exercise on a treadmill. Five ewes underwent physical training for 3 wk prior to measurement. An increase in heart rate with no change in stroke volume was observed following exercise in both trained and untrained ewes. Total uterine blood flow was not changed following exercise, but distribution was altered in favor of the placenta. Blood flow was evenly distributed within the placenta before and after exercise. The redistribution of flow to the placenta that occurs after exercise. tphe redistribution of flow to the placenta that occurs after exercise might represent a compensatory mechanism for the fetus. 相似文献
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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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Intestinal absorption and retention of cadmium in neonatal rat 总被引:1,自引:0,他引:1
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Cooling the tips of micropipettes pulled from filament-containing capillary glass dramatically increases the rate and completeness of filling with a variety of electrolyte solutions. In tests with solutions containing horseradish peroxidase this method increased the completeness of filling by more than two orders of magnitude. 相似文献