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61.
Effects of a new antiarrhythmic drug, E047/1, on atrial fibrillation were studied. Atrial conduction velocity and effective refractory period (ERP), electrocardiogram parameters (RR, PR, QRS, QT, and QTc intervals), systolic and diastolic blood pressure, and plasma concentrations of E047/1 were determined during the first 30 min after sequential administration of 1, 3, and 6 mg/kg of E047/1 in polysorbate 60 (Tween 60) to anesthetized, opened-chest dogs with vagally induced atrial fibrillation. Epicardial mapping (using 224 unipolar electrodes) was used to determine atrial fibrillation cycle length and activation sequence before and after drug administration. E0471, 3 mg/kg, prevented atrial fibrillation reinduction, and 6 mg/kg terminated atrial fibrillation. E047/1, 6 mg/kg, increased atrial ERP from 124 +/- 9 to 168 +/- 14 ms (p < 0.05). Conduction velocity decreased from 103 +/- 4 cm/s to 87 +/- 3 cm/s (p < 0.05). Epicardial mapping showed that under drug influence there was gradual reduction of wavelet number until termination of the reentrant excitation. Atrial fibrillation cycle length increased before atrial fibrillation termination from 93 +/- 4 to 137 +/- 12 ms (p < 0.05). The ability of E047/1 to terminate and prevent reinduction of experimental atrial fibrillation appears associated more with a significant prolongation of the atrial ERP than with a slowing of conduction. E047/1 appears to be a promising antifibrillatory agent.  相似文献   
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The specialized plague control facilities which began being founded as a system of institutions in Russia in 1897 have made a great contribution to epidemiological well-being against quarantine and particularly menacing diseases. The developmental stages of plague control service in different periods of the country's social life and its place in the general governmental preventive and antiepidemic measures are shown. The paper emphasizes that it is expedient to maintain the antiepidemic readiness of plaque control facilities due the fact that the epidemic situation is due menacing and zoonosis is expected to aggravate in the late 20th to the early 21st centuries.  相似文献   
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Nitric oxide synthesized from l-arginine by nitric oxide synthase isoforms (NOS-I-III) is physiologically important but also can be deleterious when overproduced. Selective NOS inhibitors are of clinical interest, given their differing pathophysiological roles. Here we describe our approach to target the unique NOS (6R,1'R,2'S)-5,6,7,8-tetrahydrobiopterin (H(4)Bip) binding site. By a combination of ligand- and structure-based design, the structure-activity relationship (SAR) for a focused set of 41 pteridine analogues on four scaffolds was developed, revealing selective NOS-I inhibitors. The X-ray crystal structure of rat NOS-I dimeric-oxygenase domain with H(4)Bip and l-arginine was determined and used for human isoform homology modeling. All available NOS structural information was subjected to comparative analysis of favorable protein-ligand interactions using the GRID/concensus principal component analysis (CPCA) approach to identify the isoform-specific interaction site. Our interpretation, based on protein structures, is in good agreement with the ligand SAR and thus permits the rational design of next-generation inhibitors targeting the H(4)Bip binding site with enhanced isoform selectivity for therapeutics in pathology with NO overproduction.  相似文献   
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俄罗斯不同气候地区不同功能水体中克雷伯菌属广泛分布。克雷伯菌属可见于遭受生物、化学污染的集中供水的地表水源,无防护的地下蓄水层,缺乏有效清洁、消毒系统的饮用水。研究表明,水体中的克雷伯菌属具有致病性和毒性,对现代药物和消毒剂(氯、紫外线)具有抗性,很容易穿透进入地下蓄水层。克雷伯菌属细菌有很强的致病性(粘附力、侵袭力、磷酸酯酶、卵磷脂酶、脱氧核糖核酸酶、溶血活性),含有致病性遗传标记cnf-1。克雷伯菌属(100 CFU/dm3)可引起急性肠道感染。在不检测总大肠菌群的情况下,检测水体尤其是饮用水中的克雷伯菌属,可以评估所用水的流行病学危险。  相似文献   
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Allergenic and photosensitizing effects of organophosphorus pesticides (OPP) have been detected, as well as their destructive effect on the skin cell ultrastructure, on the body metabolism and enzymic systems, and the inhibitory effect on cholinesterase activity. Pesticide-induced changes in polyunsaturated fatty acids (PUFA) are significant in the mechanism of dermatoses development. The complex of treatment-and-prophylaxis measures includes regular dermatologic check-ups and limitation of the number of subjects handling OPP. Subjects in whom premorbid shifts have been detected, should be followed up. The therapy and prevention of the dermatoses developing as a result of exposure to pesticides may be effectively carried out with antioxidants, amino acids, vitamins, etc.; diets with the optimal PUFA-tocopherol ratio are advisable. Overalls with multiple protective physicochemical characteristics, filtering respirators and such are recommended.  相似文献   
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