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91.
92.
WG Roberts TJ Simon RG Berlin RC Haggitt ES Snyder WF Stenson SB Hanauer JE Reagan A Cagliola WK Tanaka S Simon ML Berger 《Canadian Metallurgical Quarterly》1997,112(3):725-732
BACKGROUND & AIMS: Leukotrienes (LTs) are believed to be important in the pathogenesis of ulcerative colitis (UC). The aim of this study was to determine whether inhibition of LT biosynthesis with a 5-lipoxygenase inhibitor (MK-591) induces remission in patients with mild to moderate UC. METHODS: One hundred eighty-three patients with mild to moderately active UC enrolled in this randomized parallel group, double-blind study. Patients received placebo or MK-591 at a dose of 12.5, 50, or 100 mg twice daily for 8 weeks. A subset of patients underwent rectal dialysis to determine LTB4 concentration. RESULTS: MK-591 reduced LTB4 concentrations in rectal dialysate at the final determination. The median percent of baseline LTB4 concentration for 100 mg taken twice daily was 1.4% (n = 4); for 50 mg taken twice daily, 16.5% (n = 6); for 12.5 mg taken twice daily, 12% (n = 6); and for placebo, 78% (n = 6). There was no correlation between reduction of LTB4 and remission. Patients in remission at week 8 were as follows: placebo, 9 of 44 (20.5%); 100 mg taken twice daily, 11 of 43 (25.6%); 50 mg taken twice daily, 8 of 49 (16.3%); and 12.5 mg taken twice daily, 4 of 47 (8.5%) (P > 0.10). CONCLUSIONS: MK-591 markedly inhibited LT biosynthesis, but it did not differ significantly from placebo in clinical efficacy. Inhibition of LT biosynthesis was not effective as a single therapeutic modality in active UC. 相似文献
93.
The article demonstrates an algorithm to evaluate functional state of operators exposed to ecologic hazards. The evaluation of the functional state includes analysis of the heart rhythm registered for 2 minutes. The functional state is assessed through an Indicator of Regulatory Systems Activity (IRSA), obtained by summation of all the values in modulus. IRSA values define 5 functional states: norm; functional strain moderate, marked and extreme; asthenia of regulatory systems. The algorithm suggested differs from the known ones in some features as follows. The diagnosis of heterotopic arrhythmia serves for more precise code demonstrating the heart automatism; formed on the basis of variation coefficient, the code demonstrating stability of the regulation proves the status of stable or disordered regulation; the code demonstrating activities of subcortical neural centers is formed on the basis of measured relative capacity of primary and secondary respiratory waves. 相似文献
94.
95.
SKh al-Shukri NN Petrishchev AG Gorbachev IA Mikha?lova IuA Bobkov IV Kuz''min SIu Borovets IB Savel''eva MV Korokhodkina 《Canadian Metallurgical Quarterly》1997,42(3):38-41
Continuous monitoring of dynamic changes of transcranial regional cerebral oxygenation (rSO2) was performed in 7 healthy volunteers (mean age 40.9 +/- 12.6 years; range 25-62 years) during normo- and hyperbaric oxygenation (HBO at 2.5 and at 1.95 ATA) using an INVOS 3100 cerebral oximeter. A significant change between HBO and control phase could be found in rSO2, alterations (p < 0.05; ANOVA, Tukey test). The results suggest that the calculation of rSO2 may be a useful method to monitor changes of oxygen saturation under hyperbaric conditions. However, the absolute quantification of rSO2 is useless at the moment and needs further investigation. 相似文献
96.
L Berlin 《Canadian Metallurgical Quarterly》1998,170(5):1161-1163
97.
The study of acetone cyanohydrin (ACH) showed that it is an unstable substance. Its stability in water depends on pH of water and less so on its initial concentration; water temperature and biota are insignificant. Acetone and cyanid-ion, forming from ACH, after 20 days are transformed into a complex of cyan compounds. 相似文献
98.
BS Abdrasilov RE Elemesov IuA Kim Pak Khva Din 《Canadian Metallurgical Quarterly》1995,40(11-12):16-19
The action of the dammarane triterpene glycosides Rb1 and Rg1 and their aglycones 20(S) protopanaxatriole and 20(S) protopanaxadiole from Korean ginseng on permeability of bilayer lipid membranes formed of monolayers was studied. RgI, protopanaxatriole and protopanaxadiole in concentrations of 3, 0.5 and 30 micrograms/ml respectively formed single ionic channels in the water phase on the membrane side containing cholesterol. The channel conductivity was 5 to 30 pSm in 1 M KCl. The ionic channels were more selective with respect to K+ as compared to Cl-. Rb1 was also able to increase the conductivity of the lipid membranes. However, no jumps in the current characteristics of the single channels were detected. All the substances in high concentrations on one side of the membrane independently of the cholesterol content induced fluctuation of the high amplitude current (from several tens of pSm to several hundreds of nSm). 相似文献
99.
IuA Poroshina IS Gushchin VG Chitaeva SM Shvets AA Zernov 《Canadian Metallurgical Quarterly》1995,67(10):33-35
The examination of 11 urticaria pigmentosa (UP) patients included allergological history, skin prick, scarification tests and intracutaneous tests with noninfectious and bee poison allergens, total and specific serum IgE measurements, in vitro reaction of histamine release from peripheral blood basophils induced by bee poison. The response of mastocytosis patients to insect sting was characterized by a rapid (within 5 min) development of severe systemic reactions or shock. The skin reactions and serum antibodies to bee poison were not registered in 9 of 11 patients. They also had a negative reaction of allergen-specific histamine release from basophils. This gives evidence for nonimmunological, pseudoallergic mechanism of the shock reaction. The latter can be prevented by bee poison immunotherapy. IgE-antibody-mediated allergic reaction to bee sting could not be excluded in 2 patients. For them specific immunotherapy with bee poison, possibly with purified poison preparations containing the allergens alone, are indicated. 相似文献
100.