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991.
992.
The relationship among impaired selenium status, lipid peroxidation, and liver function was examined in 19 hospitalized patients with severe alcoholic cirrhosis. Plasma selenium was found to be significantly lower (mean±SD: 54±13 μg/L) than in healthy controls (83±11 μg/L) and plasma malondialdehyde, assessed as thiobarbituric acid reactants, which reflects lipid peroxidation, was increased (2.0±1.2 μmol/L vs <1.2 μmol/L in controls). The mean14C aminopyrine breath test, an indicator of liver function, was lower than normal (2.7±1.9 vs 6.3±0.9% in controls) and found to be significantly correlated with plasma selenium (r=0.59,p<0.05). A prospective, randomized selenium supplementation trial was conducted in a group of 16 patients who received either daily 100 μg selenium as enriched yeast during 4 mo or a placebo. Among the 10 patients who completed the study, plasma selenium significantly increased in the supplemented group (n=4; before: 58±10 μg/L, and after 101±12 μg/L,p<0.01) contrary to the placebo group (n=6, before: 47±10 μg/L, after: 57±9 μg/L, n.s.),14C aminopyrine breath test improved in three out of four selenium-supplemented patients and in three out of six placebo patients, but the small number of patients did not allow statistical evaluation. These results demonstrate that low selenium status in alcoholic cirrhosis is correlated to liver function and could be improved by supplementation. 相似文献
993.
Jakobsen Hans Henrik; Halvorsen Elisabeth; Hansen Benni Winding; Visser Andre W. 《Journal of plankton research》2005,27(8):775-785
Feeding experiments were conducted with the ambush-feeding copepodAcartia tonsa and the feeding-current-generating copepod Temoralongicornis. The copepods were offered a mixed diet of the dinoflagellateHeterocapsa triquetra and the ciliate Balanion comatum of similarcell size. The dinoflagellate was offered at a constant concentrationof 1015 cells mL1, whereas the ciliate was offeredat a variety of concentrations, ranging from 7 to 57 cells mL1.Copepods with different feeding modes possess different mechanismsfor prey detection, suggesting that the two copepods would responddifferently to the two prey types. Both copepods had significantlyhigher clearance rates on the highly motile ciliate than onthe less motile dinoflagellate. In encounters between A. tonsaand its prey, we argue that this is due to the higher hydromechanicalsignal generated by the ciliate. The advection feeding copepodT. longicornis fed on the two prey according to their relativeconcentrations; in this case, we suggest that although B. comatumis capable of detecting feeding-current-generating predators,the feeding current velocity generated by T. longicornis isgreater than the escape velocity of this ciliate. 相似文献
994.
995.
996.
Increase of the anti-HIV activity of D4T in human T-cell culture by the use of the sate pronucleotide approach 总被引:1,自引:0,他引:1
Jean-Luc Girardet Christian P rigaud Anne-Marie Aubertin Gilles Gosselin Andre Kirn Jean-Louis Imbach 《Bioorganic & medicinal chemistry letters》1995,5(24):2981-2984
The bis(S-acetyl-2-thioethyl) phosphotriester derivative of 2′,3′-didehydro-2′,3′-dideoxythymidine has been synthesized and evaluated for its inhibitory effects on the replication of HIV-1 in several cell culture systems. This pronucleotide showed potent anti-HIV activity and proved to be significantly superior to the parent nucleoside with regard to the antiviral efficiency. 相似文献
997.
An indirect fluorescent-antibody (FA) procedure employing soluble antigen fixed onto an artificial matrix was developed, and a mechanical means for reading of test results was devised. The method employs two small cellulose acetate paper discs for each test. One disc contains soluble antigen diluted in 1% bovine serum albumin (BSA); the other contains only 1% BSA and serves as a control. After testing by the indirect FA procedure, the results of the tests are read on a fluorometer fitted with a paper chromatogram door. The instrument is set at zero with the control disc as a blank, and the specific fluorescence of the antigen disc is determined. Findings obtained with homologous and heterologous antisera indicated that the method yields excellent results. The soluble antigen fluorescent-antibody technique has definite advantages over the conventional indirect FA procedures. (i) The investigator may objectively select the antigen to be employed. (ii) It is possible to obtain objective mechanical reading of test results rather than the highly subjective readings required by conventional methods. (iii) The system compensates for any nonspecific fluorescence contributed either by the serum (e.g., drugs) or by free fluorescein in the conjugated antiserum. 相似文献
998.
Richard Evans Schultes J. P. Fulton John W. Thieret Richard Evans Schultes Andre F. Clewell Wm. T. Penfound W. W. Jeffrey Richard M. Klein Richard M. Klein Wm. T. Penfound Lawrence Kaplan John W. Thieret William D. Reese Eugene C. Ogden Frank W. Gould William D. Reese Donovan S. Correll Richard Evans Sciiultes Richard Evans Schultes Mildred E. Mathias Richard Evans Schultes Rtchard M. Klein Richard Evans Schultes Richard Evans Schultes Charles T. Mason JR. Mildred E. Mathtas John W. Thieret Gordon Stuart Johnston Áskell Löve R. E. Schultes Sigmond L. Solymosy Laery W. Jones Darrell Pratt Hans R. Schmidt Ralph L. Hossfeld Philip L. Johnson José Cuatrecasas Adam F. Szczawinski Ida K. Langman M. L. Stiff Shiu-Ying Hu Eldon J. Gardneb 《Economic botany》1965,19(4):416-446
999.
1000.
Changgui Shi MD Vaskar Das PhD Xin Li MD PhD Ranjan Kc PhD Sujun Qiu MD InSug O‐Sullivan PhD Richard L. Ripper CVT Jeffrey S. Kroin PhD Fackson Mwale PhD Atiyayein A. Wallace MS Bingqian Zhu MSN Lan Zhao PhD Andre J. van Wijnen PhD Mingliang Ji MD PhD Jun Lu MD PhD Gina Votta‐Velis MD PhD Wen Yuan MD Hee‐Jeong Im PhD 《Journal of cellular physiology》2018,233(10):6589-6602