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排序方式: 共有207条查询结果,搜索用时 15 毫秒
31.
L E Panin N G Biushkina L M Poliakov 《Biulleten' eksperimental'no? biologii i meditsiny》1992,114(7):34-36
Human and serum lipoproteins interaction with steroid hormones (corticosterone and hydrocortisone) were studied. Methods of fluorescence quenching titration and equilibrium dialysis were used for quantitative evaluation of VLDL, LDL and HDL glucocorticoids binding ability. Association constants were found to be 0.6-2.0 x 10 M for corticosterone and 4.0-8.0 x 10 M for hydrocortisone. The number of binding sites ranged from 3 to 300 for different classes of lipoproteins. Our data suggest high specificity of serum lipoproteins binding with corticosterone and hydrocortisone. 相似文献
32.
V E Lankin A M Gerasimov V M Poliakov L A Koroleva V D Antonenkov S M Gurpvich 《Biokhimii?a (Moscow, Russia)》1978,43(2):235-239
The activities of enzymatic systems generating and destroying peroxides and the lipid peroxide content in neoplastic rat liver and 3,4-benzpyrene-induced sarcoma were studied. The tumour was characterized by high activity of glutathione peroxidase and low activity of catalase. No urate- and glycolate oxidases or ascorbat dependent peroxidation of lipids and lipid peroxides were found in the tumour. In the liver of neoplastic animals the activities of glutathione peroxidase and NADPH-dependent system of microsomal phospholipid peroxidation and the lipd peroxides content were increased, whereas the activities of catalase and urate oxidase were decreased. 相似文献
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Deepika S. Darbari Zhengyuan Wang Minjung Kwak Mariana Hildesheim James Nichols Darlene Allen Catherine Seamon Marlene Peters-Lawrence Anna Conrey Mary K. Hall Gregory J. Kato James G. Taylor VI 《PloS one》2013,8(11)
Background
Frequent painful vaso-occlusive crises (VOCs) were associated with mortality in the Cooperative Study of Sickle Cell Disease (CSSCD) over twenty years ago. Modern therapies for sickle cell anemia (SCA) like hydroxyurea are believed to have improved overall patient survival. The current study sought to determine the relevance of the association between more frequent VOCs and death and its relative impact upon overall mortality compared to other known risk factors in a contemporary adult SCA cohort.Methods
Two hundred sixty four SCA adults were assigned into two groups based on patient reported outcomes for emergency department (ED) visits or hospitalizations for painful VOC treatment during the 12 months prior to evaluation.Results
Higher baseline hematocrit (p = 0.0008), ferritin (p = 0.005), and HDL cholesterol (p = 0.01) were independently associated with 1 or more painful VOCs requiring an ED visit or hospitalization for acute pain. During a median follow-up of 5 years, mortality was higher in the ED visit/hospitalization group (relative risk [RR] 2.68, 95% CI 1.1-6.5, p = 0.03). Higher tricuspid regurgitatant jet velocity (TRV) (RR 2.41, 95% CI 1.5-3.9, p < 0.0001), elevated ferritin (RR 4.00, 95% CI 1.8-9.0, p = 0.001) and lower glomerular filtration rate (RR=2.73, 95% CI 1.6-4.6, p < 0.0001) were also independent risk factors for mortality.Conclusions
Severe painful VOCs remain a marker for SCA disease severity and premature mortality in a modern cohort along with other known risk factors for death including high TRV, high ferritin and lower renal function. The number of patient reported pain crises requiring healthcare utilization is an easily obtained outcome that could help to identify high risk patients for disease modifying therapies.Trial Registration
ClinicalTrials.gov NCT00011648 http://clinicaltrials.gov/ 相似文献36.
P Ia Grigor'ev E P Iakovenko N A Agafonova A S Prianishnikova I P Soluianova P V Guliaev A N Poliakov I N Usankova E V Talanova A V Iakovenko I V Vasil'ev N G Rumiantseva N A Slobodkina 《Antibiotiki i khimioterapii͡a》2000,45(6):33-39
Within 1968-1997 the authors studied the steps of introduction of the achievements of the medical science, technology and pharmacology to therapy of exacerbations and complications of peptic ulcer (PU). The scientific and practical value of endoscopic, histological, biochemical and bacteriological examinations in the improvement of the methods of pharmacotherapy of exacerbations and complications of PU was shown. Three phases of the PU development were indicated by the clinical signs and results of esophagogastroduodenoscopy, target biopsy and histological examinations. These data and available scientific achievements were assumed as a basis for the design of optimal drug combinations and their introduction to the medical practice. The use of such combinations made it possible to prevent relapses and life-threatening complications of the disease in the overwhelming majority of the patients. The best results of the pharmacotherapy were recorded in the years (1988-1997) when the drug combinations began to be used. The combinations provided eradication of Helicobacter pylori in the gastroduodenal mucosa and it was proved that in all the patients with PU and the relapsing lesions in the duodenum and in the overwhelming majority of the patients with gastric ulcer the disease developed at the background of chronic active gastroduodenitis associated with H.pylori. The success of the pharmacotherapy in the patients with PU was due to the use of the rational combinations of antibacterial and antisecretory agents. 相似文献
37.
I P Chernov A S Poliakov S B Akopov L G Nikolaev T L Azhikina M B Kostina E D Sverdlov 《Bioorganicheskaia khimiia》1999,25(4):275-281
From a library of sequences binding preferentially to nuclear matrix (matrix attachment regions, MARs), a fragment of about 300 bp in length (CEA (carcinoembryonic antigen)-MAR) was isolated and characterized. The CEA-MAR sequence was found in more than ten loci of chromosome 19 containing elements similar to genes of the CEA family. No sequences of this group were found on other human chromosomes. Two CEA-MAR-containing loci were sequenced, and sequences for another seven loci were found in GenBank. A comparative analysis of CEA-MARs and the flanking sequences is reported. Based on the sequence of the CEA-containing chromosome 19 loci, a hypothetical model of the domain structure of a 2-Mb chromosome region was constructed and the mutual arrangement of CEA-MARs and genes of CEA family was elucidated. The CEA-MARs were located 5-20 kb downstream of the CEA genes. These results suggest that the duplication unit of the CEA family may coincide with chromatin domains containing these genes. 相似文献
38.
T. Michael Redmond Eugenia Poliakov Stephanie Kuo Preethi Chander Susan Gentleman 《The Journal of biological chemistry》2010,285(3):1919-1927
The mechanism of retinol isomerization in the vertebrate retina visual cycle remains controversial. Does the isomerase enzyme RPE65 operate via nucleophilic addition at C11 of the all-trans substrate, or via a carbocation mechanism? To determine this, we modeled the RPE65 substrate cleft to identify residues interacting with substrate and/or intermediate. We find that wild-type RPE65 in vitro produces 13-cis and 11-cis isomers equally robustly. All Tyr-239 mutations abolish activity. Trp-331 mutations reduce activity (W331Y to ∼75% of wild type, W331F to ∼50%, and W331L and W331Q to 0%) establishing a requirement for aromaticity, consistent with cation-π carbocation stabilization. Two cleft residues modulate isomerization specificity: Thr-147 is important, because replacement by Ser increases 11-cis relative to 13-cis by 40% compared with wild type. Phe-103 mutations are opposite in action: F103L and F103I dramatically reduce 11-cis synthesis relative to 13-cis synthesis compared with wild type. Thr-147 and Phe-103 thus may be pivotal in controlling RPE65 specificity. Also, mutations affecting RPE65 activity coordinately depress 11-cis and 13-cis isomer production but diverge as 11-cis decreases to zero, whereas 13-cis reaches a plateau consistent with thermal isomerization. Lastly, experiments using labeled retinol showed exchange at 13-cis-retinol C15 oxygen, thus confirming enzymatic isomerization for both isomers. Thus, RPE65 is not inherently 11-cis-specific and can produce both 11- and 13-cis isomers, supporting a carbocation (or radical cation) mechanism for isomerization. Specific visual cycle selectivity for 11-cis isomers instead resides downstream, attributable to mass action by CRALBP, retinol dehydrogenase 5, and high affinity of opsin apoproteins for 11-cis-retinal. 相似文献
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Courtney D. Fitzhugh Matthew M. Hsieh Darlene Allen Wynona A. Coles Cassie Seamon Michael Ring Xiongce Zhao Caterina P. Minniti Griffin P. Rodgers Alan N. Schechter John F. Tisdale James G. Taylor VI 《PloS one》2015,10(11)