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排序方式: 共有1427条查询结果,搜索用时 15 毫秒
71.
Itokazu GS Fischer JH Manitpisitkul P Hariharan R Danziger LH 《Pharmacotherapy》2002,22(11):1420-1425
STUDY OBJECTIVE: To investigate the effect of histamine2 (H2)-receptor antagonist-induced elevation of gastric pH on oral bioavailability of a single dose of dapsone 100 mg. DESIGN: Prospective, randomized, crossover, open-label, single-dose pharmacokinetic study. SETTING: Teaching hospital. PATIENTS: Sixteen men were enrolled in the study; data from 11 subjects were evaluable. INTERVENTIONS: Participants received two treatments separated by at least 14 days. Treatment A consisted of a single dose of dapsone 100 mg. Treatment B consisted of a single dose of dapsone 100 mg plus two doses of oral nizatidine 300 mg administered 3-4 hours apart to maintain gastric pH above 6.0. Plasma samples collected before and up to 120 hours after dapsone administration were analyzed for dapsone and monoacetyldapsone (MADDS) by high-performance liquid chromatography. Pharmacokinetic parameters were determined by noncompartmental analysis. MEASUREMENTS AND MAIN RESULTS: Gastric pH in the first 6 hours after dapsone administration was above 6.0 for a mean +/- SD of 1.1% +/- 2.9% of the time in the absence of nizatidine and 69.5% +/- 18.0% of the time during nizatidine therapy. The geometric mean dapsone maximum plasma concentration (Cmax) declined by 13% (p<0.01), and median time to Cmax occurred 2 hours later (p<0.01) with nizatidine coadministration compared with dapsone alone. Inclusion of the 90% confidence interval for the mean Cmax ratio within the equivalence interval of 0.8-1.25 demonstrated the lack of clinical significance for this modest decrease in Cmax. Neither the area under the dapsone plasma concentration-time curve from zero to infinity nor the elimination half-life of dapsone were significantly altered by nizatidine. No clinically significant changes were observed in the pharmacokinetics of MADDS with regard to coadministration of nizatidine. CONCLUSION: Elevation of gastric pH by H2-receptor antagonists, such as nizatidine, does not result in clinically important changes in the rate or extent of oral dapsone absorption. 相似文献
72.
Current health scenario in rural India 总被引:2,自引:0,他引:2
ABSTRACT: India is the second most populous country of the world and has changing socio-political-demographic and morbidity patterns that have been drawing global attention in recent years. Despite several growth-orientated policies adopted by the government, the widening economic, regional and gender disparities are posing challenges for the health sector. About 75% of health infrastructure, medical man power and other health resources are concentrated in urban areas where 27% of the population live. Contagious, infectious and waterborne diseases such as diarrhoea, amoebiasis, typhoid, infectious hepatitis, worm infestations, measles, malaria, tuberculosis, whooping cough, respiratory infections, pneumonia and reproductive tract infections dominate the morbidity pattern, especially in rural areas. However, non-communicable diseases such as cancer, blindness, mental illness, hypertension, diabetes, HIV/AIDS, accidents and injuries are also on the rise. The health status of Indians, is still a cause for grave concern, especially that of the rural population. This is reflected in the life expectancy (63 years), infant mortality rate (80/1000 live births), maternal mortality rate (438/100 000 live births); however, over a period of time some progress has been made. To improve the prevailing situation, the problem of rural health is to be addressed both at macro (national and state) and micro (district and regional) levels. This is to be done in an holistic way, with a genuine effort to bring the poorest of the population to the centre of the fiscal policies. A paradigm shift from the current 'biomedical model' to a 'sociocultural model', which should bridge the gaps and improve quality of rural life, is the current need. A revised National Health Policy addressing the prevailing inequalities, and working towards promoting a long-term perspective plan, mainly for rural health, is imperative. 相似文献
73.
Effect of ursodeoxycholic acid on hydrogen peroxide induced lipid peroxidation in sheep liver mitochondria 总被引:5,自引:0,他引:5
The effect of various concentrations of ursodeoxycholic acid (UDCA), a potent hepatoprotective agent on hydrogen peroxide-induced mitochondrial swelling was evaluated in vitro to find out the mechanism of action of the drug. Aliquots of sheep liver mitochondria were pre-incubated with various concentrations of UDCA [0-600 micrograms] and swelling was induced by hydrogen peroxide [1 mM]. Swelling was assessed at various time intervals and lipid peroxide, reduced glutathione status were also evaluated simultaneously. UDCA minimized hydrogen peroxide-induced swelling in a dose-dependent manner. Time-dependent elevation in the level of lipid peroxides was noted in mitochondria treated with hydrogen peroxide and this elevation was minimized in UDCA pre-treatment. UDCA also maintains the reduced glutathione level in mitochondria. UDCA acts against the oxidative stress imposed in liver mitochondria. It reduces lipid peroxidation-induced abnormalities such as swelling and thiol group depletion and the anti lipid peroxidative efficacy of the drug may be related to its hydrophilic nature which might protect the hydrophobic regions of the mitochondrial membranes which are prone for free radical-mediated reactions. 相似文献
74.
Mayer SP Jayabose S Tugal O Ozkaynak MF Rosenblum-Vos L Sandoval C 《Leukemia & lymphoma》2002,43(9):1881-1884
We describe a case of relapsed pediatric pre-B acute lymphoblastic leukemia (ALL) with a simultaneous presentation of an intracerebral lymphoid mass. Cytogenetic, immunophenotypic and molecular analysis (immunoglobulin heavy chain and T-cell receptor gene rearrangements) revealed that the brain neoplasm was distinct from the relapsed leukemia. We discuss the etiology of this extremely rare event, and raise issues about the clonality of lymphoid neoplasms and the behavior of hematopoietic cells within the central nervous system (CNS). 相似文献
75.
Anjaneyulu V Makarieva TN Ilyin SG Dmitrenok AS Radhika P Subbarao PV Antipin MY Nesterov VV Stonik VA 《Journal of natural products》2000,63(1):109-111
Two new diterpenoids, sarcophytins B and C (1, 2), and the previously known sarcophytin (4) have been isolated from the Indian Ocean soft coral Sarcophyton sp. Structures of 1 and 2 were established by spectral data and supported by X-ray analysis of 1. 相似文献
76.
77.
Background
Multiple Endocrine Neoplasia type 1 (MEN1, OMIM 131100) is an autosomal dominant disorder characterized by endocrine tumors of the parathyroids, pancreatic islets and pituitary. The disease is caused by the functional loss of the tumor suppressor protein menin, coded by the MEN1 gene. The protein sequence has no significant homology to known consensus motifs. In vitro studies have shown menin binding to JunD, Pem, Smad3, NF-kappaB, nm23H1, and RPA2 proteins. However, none of these binding studies have led to a convincing theory of how loss-of-menin leads to neoplasia. 相似文献78.
Mansoor JK Morrissey BM Walby WF Yoneda KY Juarez M Kajekar R Severinghaus JW Eldridge MW Schelegle ES 《High altitude medicine & biology》2005,6(4):289-300
We examined the effect of dietary supplementation with L-arginine on breath condensate VEGF, exhaled nitric oxide (NO), plasma erythropoietin, symptoms of acute mountain sickness, and respiratory related sensations at 4,342 m through the course of 24 h in seven healthy male subjects. Serum L-arginine levels increased in treated subjects at time 0, 8, and 24 h compared with placebo, indicating the effectiveness of our treatment. L-arginine had no significant effect on overall Lake Louise scores compared with placebo. However, there was a significant increase in headache within the L-arginine treatment group at 12 h compared with time 0, a change not seen in the placebo condition between these two time points. There was a trend (p = 0.087) toward greater exhaled NO and significant increases in breath condensate VEGF with L-arginine treatment, but no L-arginine effect on serum EPO. These results suggest that L-arginine supplementation increases HIF-1 stabilization in the lung, possibly through a NO-dependent pathway. In total, our observations indicate that L-arginine supplementation is not beneficial in the prophylactic treatment of AMS. 相似文献
79.
Einstein FH Atzmon G Yang XM Ma XH Rincon M Rudin E Muzumdar R Barzilai N 《Diabetes》2005,54(3):672-678
Increased visceral adiposity is a pivotal component of the metabolic syndrome. Differential gene expression patterns of fat-derived peptides (FDPs) in visceral fat and subcutaneous fat have been characterized in the fasting state. Here we examined whether delivery of nutrients differentially affects the expression of FDPs in visceral fat versus subcutaneous fat (in the fed state). We increased the rate of glucose flux into adipose tissue of normal rats (n = 16) by hyperglycemia or hyperinsulinemia using the clamp technique. Glucose uptake was associated with increased expression of FDPs, including resistin ( approximately 5-fold), adiponectin ( approximately 2-fold), leptin ( approximately 15-fold), plasminogen activating inhibitor-1 ( approximately 10-fold), and angiotensinogen ( approximately 4-fold) in visceral fat, but markedly less in subcutaneous fat. Cytokine expression derived mainly from vascular/stromal/macrophage components of adipose tissue was less dramatically increased. Infusion of glucosamine amplified the results obtained by increasing glucose uptake into adipose tissue, suggesting that flux through the hexosamine biosynthetic pathway may serve as a mechanism for "nutrient sensing." Nutrient-dependent expression of FDPs in visceral fat was also associated with increased plasma levels of several FDPs. Because a biologic sensing pathway can dynamically couple daily food intake to abnormal plasma levels of important FDPs, we challenge the practice of obtaining plasma levels after fasting to assess risk factors for metabolic syndrome. 相似文献
80.