全文获取类型
收费全文 | 311篇 |
免费 | 42篇 |
出版年
2021年 | 4篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 5篇 |
2014年 | 14篇 |
2013年 | 14篇 |
2012年 | 18篇 |
2011年 | 14篇 |
2010年 | 14篇 |
2009年 | 8篇 |
2008年 | 14篇 |
2007年 | 10篇 |
2006年 | 15篇 |
2005年 | 17篇 |
2004年 | 11篇 |
2003年 | 5篇 |
2002年 | 11篇 |
2001年 | 14篇 |
2000年 | 22篇 |
1999年 | 11篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1994年 | 3篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 10篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1986年 | 6篇 |
1985年 | 7篇 |
1984年 | 9篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1979年 | 3篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1974年 | 8篇 |
1973年 | 6篇 |
1971年 | 2篇 |
1970年 | 4篇 |
1969年 | 3篇 |
1965年 | 1篇 |
1930年 | 1篇 |
1918年 | 1篇 |
排序方式: 共有353条查询结果,搜索用时 15 毫秒
341.
342.
343.
V M Lipkin A N Obukhov A P Bogachuk I N Telezhinskaia V V Shemiakin 《Bioorganicheskaia khimiia》1985,11(11):1481-1492
The alpha- and beta-subunits of the GTP-binding protein (transducin) from cattle retina were cleaved with cyanogen bromide. 21 peptides covering 90-100% of the amino acid sequence of the alpha- and beta-subunits were isolated from the hydrolyzate. Cyanogen bromide peptides complete or partial amino acid sequence was determined, the results were compared with those by Numa and coworkers [1] and Lochrie et al. [2] at the primary structure of the transducin alpha-subunit deduced from the nucleotide sequence of the cDNA. The structure by Lochrie is shown to differ much from the true structure of the alpha-subunit; probably, the investigators isolated cDNA, corresponding to the gene for some GTP-binding protein homologous to transducin, but not to the gene for the transducin alpha-subunit. The Numa's structure also contains an error. The final primary structure of the transducin alpha-subunit is given. The protein polypeptide chain consists of 349 amino acid residues and has an acetylmethionine residue as the N-terminal residue. 相似文献
344.
Iu A Ovchinnikov V M Lipkin I N Telezhinskaia T M Shuvaeva A N Obukhov 《Bioorganicheskaia khimiia》1985,11(10):1301-1314
The complete amino acid sequence of the gamma-subunit of GTP-binding protein from cattle retina has been established. The polypeptide chain consists of 69 amino acid residues and contains an unusual sequence Cys35-Cys36. The molecular mass of the gamma-subunit is 8008,7. 相似文献
345.
T. M. Shuvaeva V. I. Novoselov E. E. Fesenko V. M. Lipkin 《Russian Journal of Bioorganic Chemistry》2009,35(5):523-537
Current ideas are discussed about the structures and mechanisms of action of proteins that have been united at present into
a family of thiol-specific antioxidants or peroxiredoxins, which protect the cells of different organisms from the action
of hydrogen peroxide. Peroxiredoxins fulfill the same function as antioxidant enzymes such as catalases and glutathione-dependent
peroxidases; however, their catalytic activity is lower than that of these enzymes. The level of expression of genes of peroxiredoxins
is increased in many pathological states accompanied by oxidative stress, and today there is direct evidence for the important
role of peroxiredoxins in the vital activity of cells. 相似文献
346.
B A Shapiro R Nussinov L E Lipkin J V Maizel 《Journal of biomolecular structure & dynamics》1987,4(5):697-706
An interactive computer system using a dot matrix approach has been developed and used to determine potentially significant features due to distortions in the B-DNA helix as a result of variations of purine and pyrimidine patterns. Sequences were compared using matrices which were generated using the Calladine-Dickerson rules (C.R. Calladine, J. Mol. Biol. 161, 343-352, 1982 and R.E. Dickerson, J. Mol. Biol. 166, 419-441, 1983). Having control over various parameters to enhance different aspects of the visual appearance of these matrices was helpful in discovering patterns that were not known a priori. Specifically, it was found that a pattern of alternating doublets of purines and pyrimidines appear to exist in regulatory regions. This event is shown to be beyond probabilistic expectation. 相似文献
347.
E. Y. Zernii D. V. Zinchenko V. I. Vladimirov I. I. Grigoriev E. E. Skorikova V. E. Baksheeva V. M. Lipkin P. P. Philippov I. I. Senin 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2014,8(1):44-49
Recoverin is a Ca2+-binding protein implicated in the Ca2+-dependent regulation of desensitization of visual receptor rhodopsin in vertebrate retinal rods. Here we report that Ca2+ sensitivity of recoverin regulating rhodopsin phosphorylation increases in the presence of the photoreceptor membranes enriched in raft structures. The observed effect is mediated by a key protein component of raft structures caveolin-1. The presence of recombinant fragment Phe81-Arg101 of the caveolin-1 cytoplasmic domain enhances Ca2+ affinity of recoverin, therefore affecting its Ca2+-dependent regulatory activity. 相似文献
348.
349.
George Lipkin Gail K. Naughton Martin Rosenberg Jean-Claude Bystryn 《Differentiation; research in biological diversity》1985,30(1):35-39
Most vitiligo sera contain antibodies to surface antigens on pigmented human melanocytes but not to human or mouse amelanotic melanoma cells. A density-dependent line of hamster amelanotic melanocytic cells (FF) produces a diffusible factor (CIF) which restores contact inhibition of growth as well as several other normal phenotypic characteristics to hamster, murine, and human melanoma cells. The ability of CIF to induce the expression of a phenotypic characteristic of pigmented human melanocytic cells, i.e., the vitiligo-related surface antigens, on hamster and mouse amelanotic melanoma cells was investigated. Vitiligo and normal sera were reacted with CIF-treated and untreated hamster and mouse amelanotic melanoma cells for both indirect-immunofluorescence assays and ELISA. Immunofluorescence testing showed that about 80% of hamster and mouse melanoma cells had pigment-cell antigens (in the absence of pigmentation) in a granular surface pattern after, but not prior to, CIF-induced morphologic reversion and confluent growth. Less than 5% of the control hamster and mouse melanoma cells expressed such antigens at confluence. These results were confirmed by ELISA. Metabolic-labeling studies with 35S-methionine showed that the vitiligo antigens were synthesized by the CIF-treated melanoma cells. The slowing of melanoma cell proliferation in isoleucine-deficient medium failed to elicit the expression of vitiligo antigens. Since antigen appearance following phenotypic reversion occurred without pigment induction, it is concluded that vitiligo-related surface antigens and pigmentation are distinct aspects of a differentiated function which may be non-coordinately expressed. The expression of pigment-cell differentiation antigens on amelanotic melanoma cells is an additional feature of the pleiotypic trans-species response to CIF. 相似文献
350.
S. Y. Filkin N. V. Chertova A. A. Zenin A. V. Lipkin A. A. Sichev D. S. Bityak 《Preparative biochemistry & biotechnology》2020,50(6):549-555
AbstractAim: The main purpose of this work was to develop new protocols for high yield purification of secretory phospholipase A2 (PLA2) and to investigate its biophysical properties.Materials and methods: We have used a Pichia pastoris expression system for PLA2 expression and two-stage chromatography for its purification. The biophysical properties of PLA2 were investigated by circular dichroism.Results: A scalable method for high yield purification of recombinant Streptomyces violaceruber PLA2 was developed. The PLA2 from S. violaceruber was expressed in the methylotrophic yeast P. pastoris. Functional active phospholipase A2 with specific activity 73?U/mg was purified with a concentration of at least 3?mg/mL. The role of different divalent ions in PLA2 thermostability were evaluated. Ca2+ and Ba2+ ions significantly increased thermostability of the enzyme. 相似文献