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31.
Kitchen LW Ross JA Hernandez JE Zarraga AL Mather FJ 《International journal of antimicrobial agents》1993,2(4):237-246
Other researchers have found that diethylcarbamazine (DEC) is effective treatment for filariasis despite a lack of demonstrated in vitro antifilarial activity. The results of our previous investigations using feline and murine leukemia virus models encouraged us to investigate the use of DEC with other infections. In our current experiments, DEC treatment was associated with lower brain fungal burden in fluconazole-treated mice following intravenous injection of Aspergillus fumigatus or increasing numbers of Cryptococcus neoformans organisms, and lower brain and kidney levels of Candida albicans following intravenous injection of increasing numbers of C. albicans. Further investigation of combined DEC and fluconazole treatment of fungal infections is warranted. 相似文献
32.
33.
目的:探讨临床常用药物对人体酸碱平衡的影响,指导临床工作。方法:用酸度计测定九种药品pH值,计算氢离子浓度。结果:偏碱性的药物有50g/L碳酸氢钠,谷氨酸钠、谷氨酸钾注射液;偏酸性的药物有盐酸精氨酸、维生素C、各种浓度葡萄糖注射液、氯化钠注射液。结论:临床上一些常用药品会影响人体的酸碱平衡,尤其在机体酸碱平衡调节发生障碍的情况下,更应谨慎。 相似文献
34.
郑国庆 《辽宁中医药大学学报》2000,(3)
复习朱丹溪有关医学文献 ,阐发其应用风药治疗血证的机制 ,主要有 :风药直接止血 ;风药升阴散火止血 ;风药散火解毒、凉血止血 ;风药炒黑止血 ;风药振脾益气止血 ;祛除致病因素 ;其它。 相似文献
35.
Interactions between imidazoline compounds and sulphonylureas in the regulation of insulin secretion
Mirna Mourtada Colin A Brown Stephen A Smith Valerie Piercy Susan L F Chan Noel G Morgan 《British journal of pharmacology》1997,121(4):799-805
- Imidazoline α2-antagonist drugs such as efaroxan have been shown to increase the insulin secretory response to sulphonylureas from rat pancreatic B-cells. We have investigated whether this reflects binding to an islet imidazoline receptor or whether α2-adrenoceptor antagonism is involved.
- Administration of (±)-efaroxan or glibenclamide to Wistar rats was associated with a transient increase in plasma insulin. When both drugs were administered together, the resultant increase in insulin levels was much greater than that obtained with either drug alone.
- Use of the resolved enantiomers of efaroxan revealed that the ability of the compound to enhance the insulin secretory response to glibenclamide resided only in the α2-selective-(+)-enantiomer; the imidazoline receptor-selective-(−)-enantiomer was ineffective.
- In vitro, (+)-efaroxan increased the insulin secretory response to glibenclamide in rat freshly isolated and cultured islets of Langerhans, whereas (−)-efaroxan was inactive. By contrast, (+)-efaroxan did not potentiate glucose-induced insulin secretion but (−)-efaroxan induced a marked increase in insulin secretion from islets incubated in the presence of 6 mM glucose.
- Incubation of rat islets under conditions designed to minimize the extent of α2-adrenoceptor signalling (by receptor blockade with phenoxybenzamine; receptor down-regulation or treatment with pertussis toxin) abolished the capacity of (+)-and (±)-efaroxan to enhance the insulin secretory response to glibenclamide. However, these manoeuvres did not alter the ability of (±)-efaroxan to potentiate glucose-induced insulin secretion.
- The results indicate that the enantiomers of efaroxan exert differential effects on insulin secretion which may result from binding to effector sites having opposite stereoselectivity. Binding of (−)-efaroxan (presumably to imidazoline receptors) results in potentiation of glucose-induced insulin secretion, whereas interaction of (+)-efaroxan with a second site leads to selective enhancement of sulphonylurea-induced insulin release.
36.
In this review the state of the art of treating patients with epilepsy in the nineties in the Netherlands is presented. It describes general strategies for treatment with antiepileptic drugs and the history of development of the classical anticonvulsant drugs. Eight new drugs, including vigabatrin, lamotrigine, felbamate, oxcarbazepine, gabapentin, tiagabine, levetiracetam and topiramate are discussed. A review of their pharmacological and clinical properties is presented. Dutch experience with these drugs is included. 相似文献
37.
论述了中药材“地区习惯用药”的由来与含义,近现代和历史上的“地区习惯用药”的实例以及产生“地区习惯用药”的原因,随品种性质判明而渐趋分化等。最后提出应该积极研究,促其分化,按其本质分类处理的建议。 相似文献
38.
A new type of ultra-short acting -blocker which might prove advantageous in treating acute arrhythmias was designed, synthesized and investigated. Based on the soft drug inactive metabolite approach, the inactive phenylacetic acid metabolite of both metoprolol and atenolol was reactivated by esterification with sulfur-containing aliphatic alcohols. Since the sulfur-containing moieties are labile to the ubiquitous esterases, the new compounds should be inactivated by a one step enzymatic cleavage back to the inactive phenylacetic acid derivative. Pharmacological and pharmacokinetic profiles of the new compounds were evaluated in rats and rabbits. Isoproterenol-induced tachycardia was inhibited with short-term infusion of each compound. This tachycardia blocking effect rapidly disappeared upon termination of infusion, while -blocking activity was 2–4-fold longer after comparable doses of the short-acting -blocker, esmolol. The rapid recovery from the -receptor blockade is believed due to fast hydrolysis of the soft drugs in the body. This is supported from in vitro results showing the tl/2 of esmolol is about 10-fold longer than the new soft drugs in rat, rabbit, dog and human blood. Hydrolysis studies in phosphate buffered solutions indicated that the esters are labile to base-catalyzed hydrolysis. However, the relative t1/2 values measured in biological media compared to phosphate buffered solution clearly support rapid enzymatic cleavage of the soft drugs. Interestingly, one of the soft -blockers, the sulfonyl ester derivative, showed a unique property of exhibiting good -receptor blocking activity without significant hypotensive action. 相似文献
39.
RATIONALE AND OBJECTIVES: The authors evaluated the cardiac tolerability of paramagnetic contrast agents for magnetic resonance (MR) angiography in an in vitro model of ischemic rat heart. MATERIALS AND METHODS: The left anterior descending coronary artery was temporarily occluded in a perfused rat heart model to induce cardiac ischemia and reperfusion. A dose of 0.4 mL of gadobenate dimeglumine, of gadopentetate dimeglumine, or of D-mannitol was injected directly into the aorta both during the ischemia and during the reperfusion period. The left ventricular pressure and heart rate were recorded. RESULTS: Myocardial ischemia resulted in decreased cardiac activity, with a reduction in left ventricular pressure and heart rate. A further decrease in cardiac activity was temporarily induced by injection of contrast medium during both the ischemic and early reperfusion phases. Less marked responses were induced by a hyperosmolal solution of mannitol. CONCLUSION: These results suggest that the transient cardiac effects induced by bolus injection of paramagnetic contrast medium may be regarded as the combined effects of the osmotoxicity of the contrast medium solution and the chemotoxicity of the contrast medium molecule. 相似文献
40.