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51.
The effects of calcium channel blockers on cyclosporine and its metabolites in renal transplant recipients 总被引:1,自引:0,他引:1
K L Tortorice K L Heim-Duthoy W M Awni K V Rao B L Kasiske 《Therapeutic drug monitoring》1990,12(4):321-328
Although calcium channel blockers have been reported to increase trough cyclosporine (CsA) blood levels, few studies have systematically examined the effects of calcium channel blockers on CsA pharmacokinetics. In the present investigation, complete pharmacokinetic profiles of CsA and its major metabolites (M1, M17, and M21) were determined in 11 verapamil-treated patients, 7 nifedipine-treated patients, and in 78 controls. Whole blood and urine levels were analyzed using high-performance liquid chromatography. Verapamil caused a 45% increase in CsA area under the curve, maximum concentration, steady-state concentration, and trough level. Metabolite 17 levels were increased in a parallel fashion, suggesting that altered CsA bioavailability rather than decreased metabolism may have caused the higher CsA levels in verapamil-treated patients. However, verapamil-induced reductions in CsA metabolism by other routes could not be ruled out. No changes in CsA or its metabolites were observed in nifedipine-treated patients. Unlike previous reports in patients treated with higher CsA doses, verapamil and nifedipine did not improve renal function in the present study. Nevertheless, the increase in CsA blood levels seen with verapamil may enhance the therapeutic cost-effectiveness of this agent in hypertensive renal transplant recipients. 相似文献
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Glucose amendment (0.5%) to the culture medium of Chlorella vulgaris reversed the algal toxicity caused by p-nitrophenol (PNP) and m-nitrophenol (MNP), only at their algistatic levels. Algistatic and algicidal concentrations of PNP and MNP, in the absence of glucose, led to the liberation of more nitrite in the culture medium. However, addition of glucose inhibited nitrite formation. 相似文献
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Insulin containing gelatin microspheres (IGM) with and without soyabean trypsin inhibitor (TI) were pre-pared and coated with enteric polymers to protect them from degradation in stomach and to release the insulin upon reaching the intestine. Four types of coated IGM were prepared: (i) IGM coated with natural polymers (chitosan inner coat-alginate outer coat), (ii) IGM-TI coated with cellulose acetate phthalate; (iii) IGM-TI coated with cellulose acetate butyrate, and (iv) IGM-TI coated with natural polymers (chitosan inner coat-alginate outer coat). The protective efficiency of uncoated and four types of coated microspheres to-ward digestive enzymes such as pepsin and trypsin was evaluated under simulated physiological conditions. The microspheres were characterized for their insulin content and particle size. The morphology of the micro-spheres was studied using scanning electron micros-copy. The in vitro release studies of insulin from uncoated and coated microspheres indicated that the release followed a zero-order pattern, prolonging for 6 days from 2 days in the case of uncoated spheres. The uncoated and coated microspheres containing insulin (20 IU/kg) were orally administered to albino Wistar rats by stomach tube, and insulin absorption was evaluated by assessing the hypoglycemic effect in normal and diabetic rats. A significant and continuous hypoglycemic effect was observed in diabetic rats following oral administration of coated IGM containing TI when compared to the effect following administration of coated IGM without TI. 相似文献
57.
采用紫外分光光度法测定长春丁汀片的含量。长春西汀片在274mm波长处有最大吸收,方法线性范围是10-20μg/ml,回归方程Y=30.092X+0.0533,r=0.9999,平均回收率为101.38%(n=5,RSD=0.71%)。 相似文献
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P Coni G Pichiri-Coni G M Ledda-Columbano E Semple S Rajalakshmi P M Rao D S Sarma A Columbano 《Cancer letters》1992,61(3):233-238
The present study was undertaken to determine the effect of two different types of liver cell proliferative stimuli, namely compensatory regeneration and direct hyperplasia on DNA synthesis of normal and preneoplastic isolated hepatocytes. Platelet-poor plasma (PPP) isolated from male Wistar rats treated with three different hepato-mitogens, lead nitrate (LN), cyproterone acetate (CPA) and ethylene dibromide (EDB), or subjected to surgical partial hepatectomy (PH), was tested for its ability to stimulate DNA synthesis in normal and preneoplastic hepatocytes in primary cultures. Induction of DNA synthesis was detected as early as 30 min after CPA, EDB and PH administration and persisted up to 5 days after the LN administration. In addition, hepatocytes isolated from preneoplastic liver nodules were also able to respond in culture to the DNA synthesis stimulus induced by these factors. 相似文献
60.
The introduction of different types of pollutants like those from industrial effluence, bye-products from petro-chemical industries, pesticidal application, wastages of nuclear power industries, etc. is viewed seriously by the society. For the control of vectors of disease the adoption of environmental management is, therefore, imperative. The physical methods like drainage of excess and waste water, making water unsuitable for vector breeding by adopting various indigenous methods in vogue, the intra and inter-sectrol coordination and community based activities are identified as the basic approaches for achieving this goal. Minimising the potentiality of vector breeding through source reduction and water management is thought to be the simplest, cheapest and most permanent method. For the society having varying types of habitation and varying degree of habitational facilities like planned housing, water supply and disposal, sanitation and organized anti-vector measures, the adoption of environmental management to exercise check over vector population is a promising proposition. The suitability of such an approach has already been demonstrated by MRC, (ICMR), Delhi and V.C.R.C., Pondicherry. The implementation of these methods is to be initiated right from Primary Health Centre and district level onwards and community is to be motivated to the extent that the various methods of environmental management for vector control are adopted in the routine way of life. In the present article these ideas have been touched upon and various methods of environmental management described in brief. In addition what other Governmental agencies are required to do in order to effectively implement environmental management methods are briefly enlisted. 相似文献