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981.
A Kahan J Y Devaux B Amor C J Menkes S Weber A Venot F Guerin M Degeorges J C Roucayrol 《The Journal of rheumatology》1988,15(9):1395-1400
Primary scleroderma myocardial disease may be due in part to myocardial ischemia caused by a disturbance of the coronary microcirculation. We evaluated the effect of the calcium channel blocker nicardipine on myocardial perfusion assessed by thallium-201 scanning in 16 patients with systemic sclerosis. Thallium-201 single photon emission computerized tomography was performed at baseline and 90 min after 40 mg of oral nicardipine. The mean (+/- SD) number of left ventricular segments with perfusion defects significantly decreased from 6.0 +/- 2.0 at baseline to 4.1 +/- 2.3 after nicardipine (p less than 0.01). The mean global perfusion score significantly increased from 10.2 +/- 1.9 at baseline to 11.9 +/- 2.6 after nicardipine (p less than 0.02). Our study demonstrates short-term improvement in thallium-201 myocardial perfusion with nicardipine in patients with systemic sclerosis. 相似文献
982.
983.
984.
Methionine adenosyltransferase (MAT) activity, and the concentration of its reaction product, S-adenosylmethionine (AdoMet), were measured in the lenses of rats of different ages; ranging from 1 day of age to over 1 yr. The highest specific activity of MAT was found in the lenses of the one day old rats (sp. ac. 0.327 units/mg-1 protein). After 1 week the specific activity had dropped to 0.067, and by 6 weeks had declined to adult levels (0.02 units/mg-1 protein). AdoMet concentrations were measured by HPLC in perchloric acid extracts. The highest concentration of AdoMet was found in the lenses of day-old rats (48.2 microM), and gradually declined with increasing age, reaching 5.5 microM in the oldest rats. In addition, the specific activity of MAT was found to be higher in the lens epithelium than in the cortex plus nucleus. The specific activity of MAT is almost an order of magnitude higher in the lens epithelial fraction (0.099 units mg-1 protein) than in the combined cortex plus nucleus fraction (0.011 units mg-1 protein). 相似文献
985.
986.
After induction of diabetes with streptozocin (STZ-D) in rats, we measured vasoactive intestinal polypeptide (VIP) content in sciatic nerve and spinal cord obtained from nondiabetic, untreated STZ-D, and insulin-treated STZ-D rats. Eight weeks after the onset of diabetes, caudal nerve conduction velocity (NCV) in the untreated STZ-D rats (n = 13) was slower than in the controls (n = 11; mean +/- SE 30.9 +/- 0.6 vs. 41.4 +/- 1.8 m/s, P less than 0.001). The decrease in NCV was less marked in the insulin-treated STZ-D rats (n = 11; 36.3 +/- 0.9 m/s, P less than 0.05 vs. control). VIP content in sciatic nerve decreased in the untreated STZ-D rats (1.33 +/- 0.23 ng/g wet wt) compared with the other groups (control, 3.10 +/- 0.44, P less than 0.01; insulin-treated STZ-D, 2.44 +/- 0.55, P less than 0.05). However, in spinal cord, VIP content was not significantly different among the three groups. The VIP levels in sciatic nerve showed a positive correlation with NCV (r = 0.430, P less than 0.01). In addition, an inverse correlation between VIP levels and blood glucose levels was observed (r = -0.5624, P less than 0.001). NCV was also inversely correlated with blood glucose levels (r = -0.7662, P less than 0.001). Together with a previous morphological study, these findings suggest a possible causal relationship between reduced VIP content and diabetic neuropathy. 相似文献
987.
988.
The hypoglycaemic effect of Anthocleista vogelii was studied in mice, rats and rabbits. Aqueous extract of the plant obtained by infusion from finely pulverized root was used. The extract (100, 400 and 800 mg/kg) induced significant hypoglycaemic activity in a dose-related fashion at 2 h after oral administration in mice and rats with ED25 of 250 mg/kg and 350 mg/kg respectively. The extract (800 mg/kg, orally) similarly induced statistically significant lowering of blood glucose levels at 8 h in normoglycaemic rabbits. The extract (400 mg/kg and 800 mg/kg, orally) also caused reduction of blood glucose levels in alloxan-induced diabetic animals. The results of this study indicate that the aqueous extract of the roots of Anthocleista vogelii possess favourable hypoglycaemic activity both in normo and hyperglycaemic animals compared to chlorpropamide as a standard. 相似文献
989.
K Morikawa M Kakiuchi M Fukuoka H Kato Y Ito Y Gomi 《Japanese journal of pharmacology》1990,52(3):405-411
We evaluated the effects of various intravenously administered drugs, which had been shown to influence bladder function in anesthetized and/or conscious rats, on the cystometrogram in conscious restrained-denervated rats (produced by transection of the hypogastric nerve) placed in a restraining cage in comparison to those in conscious restrained-intact rats (with the hypogastric nerve intact) placed in a restraining cage. The bladder capacity in the restrained-denervated rats was smaller than that in restrained-intact rats and did not change when they were transferred to a wide cage, but the bladder capacity of the restrained-intact rats decreased following transfer to the wide cage. Therefore, the activity of the hypogastric nerve in conscious rats appears to be stimulated by restraint. Atropine suppressed the amplitude of the micturition contraction (time to micturition in the cystometrogram). In the restrained-denervated rats, thiopental and indomethacin increased the bladder capacity at almost the same doses as those in restrained-intact rats, but it took a higher dose of morphine to increase the bladder capacity than in restrained-intact rats. These findings suggest that cystometrography in restrained-denervated rats is a useful method for evaluating the effect of a newly developed agent on bladder function without any influence from the hypogastric nerve. 相似文献
990.
P De Wals H Dolk F Bertrand Y Gillerot J A Weatherall M F Lechat 《Revue d'épidémiologie et de santé publique》1988,36(4-5):273-282
The EUROCAT programme is a concerted action of the European Economic Community for the epidemiologic surveillance of congenital anomalies. Surveillance is based on a network of regional registries coordinated by a central registry. The programme started in 1979 and by 1987, 23 centres were participating, covering together more than 300,000 births per year. The surveillance process implies the selection of the anomalies possibly associated with environmental teratogens or mutagens, the definition of abnormal variations in the rate of these anomalies (the alarms), the establishment of base-line rate and the continuous monitoring of rate. The programme is evaluated by reference to four criteria: the sensitivity of the system in detecting teratogens or mutagens, the specificity of alarms, the rapidity in warning of alarm and in investigating their causes, and the programme efficiency expressed as its cost-utility ratio. 相似文献