全文获取类型
收费全文 | 4481篇 |
免费 | 400篇 |
国内免费 | 256篇 |
专业分类
5137篇 |
出版年
2024年 | 14篇 |
2023年 | 107篇 |
2022年 | 174篇 |
2021年 | 162篇 |
2020年 | 177篇 |
2019年 | 208篇 |
2018年 | 176篇 |
2017年 | 159篇 |
2016年 | 159篇 |
2015年 | 175篇 |
2014年 | 204篇 |
2013年 | 352篇 |
2012年 | 224篇 |
2011年 | 209篇 |
2010年 | 152篇 |
2009年 | 219篇 |
2008年 | 231篇 |
2007年 | 263篇 |
2006年 | 224篇 |
2005年 | 147篇 |
2004年 | 148篇 |
2003年 | 135篇 |
2002年 | 130篇 |
2001年 | 84篇 |
2000年 | 74篇 |
1999年 | 67篇 |
1998年 | 89篇 |
1997年 | 55篇 |
1996年 | 55篇 |
1995年 | 59篇 |
1994年 | 43篇 |
1993年 | 44篇 |
1992年 | 40篇 |
1991年 | 29篇 |
1990年 | 25篇 |
1989年 | 25篇 |
1988年 | 25篇 |
1987年 | 18篇 |
1986年 | 15篇 |
1985年 | 45篇 |
1984年 | 51篇 |
1983年 | 34篇 |
1982年 | 39篇 |
1981年 | 22篇 |
1980年 | 19篇 |
1979年 | 8篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1976年 | 4篇 |
1974年 | 4篇 |
排序方式: 共有5137条查询结果,搜索用时 0 毫秒
1.
Nataly Mancette Rijensky Netta R. Blondheim Shraga Eilon Barnea Nir Peled Eli Rosenbaum Aron Popovtzer Solomon M. Stemmer Alejandro Livoff Mark Shlapobersky Neta Moskovits Dafna Perry Eitan Rubin Itzhak Haviv Arie Admon 《Molecular & cellular proteomics : MCP》2020,19(8):1360-1374
Highlights
- •Sufficient tumor tissues are often unavailable large HLA peptidome discovery.
- •Using patient derived xenograft (PDX) tumors can overcome this limitation.
- •The large PDX HLA peptidomes expand significantly those of the original biopsies.
- •The HLA peptidomes of the PDX tumors included many tumor antigens.
2.
Lars Terenius Björn Johansson 《Biochemical and biophysical research communications》2010,396(1):140-142
This mini-review outlines the opioid systems and their roles primarily as related to reward and compulsive drug/alcohol intake. The central role is taken by the mu-opioid receptor, target for opiate analgesics and also a central target in compulsive alcohol abuse, alcoholism. The mu-opioid receptor and the cognate opioid neuropeptides from proenkephalin and proopiomelancortin are members of a superfamily of opioid systems, each with unique and still to be defined roles in the central nervous system. 相似文献
3.
4.
Sisinthy Shivaji 《Bioscience reports》1988,8(6):609-618
Proteins present in the seminal plasma of mammals are known to influence functions associated with ejaculated spermatozoa such as motility, capacitation, acrosome reaction and fertilising ability. The proteins isolated and characterised so far influence only one of the above functions of spermatozoa. Seminalplasmin, a protein isolated from the seminal plasma of bull is exceptional in that it influences many of the above spermatozoal functions. It is also a potent antimicrobial protein and capable of lysing microbial and mammalian cells. The physiological function of seminalplasmin as nature's own antifertility agent is discussed. 相似文献
5.
Kirsi-Marja Marnela Vince Varga Gábor Dibó Pekka Lähdesmäki 《Journal of neurochemistry》1987,48(4):1090-1092
To elucidate the position of the peptide bond in glutamyl-taurine this dipeptide was extracted from calf brain synaptic vesicles and subjected to paper electrophoresis. It was analyzed further in an automatic amino acid analyzer prior and subsequent to acid hydrolysis. Both alpha- and gamma-forms were found to be present in approximately equal amounts. 相似文献
6.
David T. Osuga Milton S. Feather Mena J. Shah Robert E. Feeney 《Journal of Protein Chemistry》1989,8(4):519-528
Amino acids and peptides have been attached to the C-6 hydroxyls of the galactose and the N-acetylgalactosamine by first oxidizing the C-6 hydroxyls to the aldehydes by galactose oxidase in the presence of small amounts of catalase, followed by reductive amination (-amino group) in the presence of cyanoborohydride. The activity of oxidized antifreeze glycoprotein was >70% of the original, and considerable activity has been retained with some substitutions on reductive amination using cyanoborohydride. The following were some activities retained (as compared with the oxidized antifreeze glycoprotein): Gly, 64; (Gly)2, 88; (Gly)3, 82; (Gly)4, 70; Gly-Gly-NH2, 44, Gly-Glu, 13; Gly-Leu, 40; Gly-Tyr, 57; Gly-Gly-Leu, 50; Gly-Gly-Phe, 30; and Gly-Gly-Val, 35. On amino acid analysis of acid hydrolysates, some release of the amino acid attached by amination occurred; e.g., Gly-Tyr gave 0.26 Gly and 0.49 Tyr per disaccharide. 相似文献
7.
Summary Immunohistochemical properties of the terminal nerve network in the rat heart were assessed by use of the elution-restaining method. The colocalization of the enzymes involved in catecholamine synthesis (tyrosine hydroxylase — TH, dopamine--hydroxylase — DBH) as well as the respective distributions of the neuropeptides associated with the adrenergic nervous system (neuropeptide tyrosine — NPY, C-terminal flanking peptide of neuropeptide Y — C-PON) were studied in series of serial sections throughout the interatrial septum and the atrioventricular junction. Our data suggest that ganglion cells of sulcus terminalis as well as the epicardial ganglia enclosed between the superior vena cava and ascending aorta are VIP- and TH-negative, but neuropeptide Y- and DBH-immunoreactive. They give rise to three intraseptal nerves directed towards the specialised structures of the atrioventricular junction. These nerve fascicles contain abundant, thick TH-immunoreactive nerve fibres and scarce, thin NPY- and DBH-immunoreactive fibres. The cell bodies of the intramural ganglion cells localized between the right and left branches of the bundle of His (Moravec and Moravec 1984) are strongly TH- and DBH-immunoreactive. They are innervated by thick nerve fibres having the same immunohistochemical properties (NPY- and DBH-immunoreactivities) as those of a subpopulation of the epicardial ganglion cells and seem to supply some of the TH-immunoreactive nerve fibres directed via the intraseptal nerves to the epicardial ganglia. The existence of a multicomponent nerve network, characterized by a reciprocal innervation of the sinus node and atrioventricular node areas, is suggested by our immunohistochemical data. 相似文献
8.
Biserka Mulac-Jericevic Taghi Manshouri Tsuyoshi Yokoi M. Zouhair Atassi 《Journal of Protein Chemistry》1988,7(2):173-177
A set of 18 synthetic uniform overlapping peptides spanning the entire extracellular part (residues 1–210) of the -subunit of human acetylcholine receptor were studied for their binding activity of125I-labeled -bungarotoxin and cobratoxin. A major toxin-binding region was found to reside within peptide 122–138. In addition, low-binding activities were obtained with peptides 34–49 and 194–210. It is concluded that the region within residues 122–138 constitutes a universal major toxin-binding region for acetylcholine receptor of various species. 相似文献
9.
Dr. Yalcin Cetin 《Cell and tissue research》1988,253(1):173-179
Summary It has long been disputed whether mammalian enterochromaffin (EC-) cells contain a peptide in addition to serotonin. Previous immunohistochemical studies have provided evidence for the presence of enkephalins in EC-cells. These findings, however, are equivocal. Therefore, the problem of opioid peptides in EC-cells has been re-examined in the gastro-intestinal mucosa of dog, guinea-pig and man. A battery of antisera against derivatives of pro-opiomelanocortin, pro-enkephalin and pro-dynorphin have been applied to semithin serial sections of the tissues, in combination with fluorescence histochemistry and serotonin immunocytochemistry. Our findings indicate that EC-cells of the investigated species contain pro-dynorphin-related peptides, i.e. dynorphin A and -neo-endorphin, but no derivatives from pro-opiomelanocortin or pro-enkephalin. Since remarkable interspecies variations occur with respect to the number and staining characteristics of opioid immunoreactive EC-cells, it is concluded that pro-dynorphin shows specific routes of post-translational processing depending upon the species and the gastro-intestinal segment investigated. Future studies should focus on the mutual relationships between serotonin and dynorphins and on the physiological significance of these peptides in the gastrointestinal tract.Part of the results were presented at the Bayliss and Starling Society National Scientific Meeting 1985, London (Cetin et al. 1985) 相似文献
10.
Igor A. Krasheninnikov Anton A. Komar Ivan A. Adzhubei 《Journal of Protein Chemistry》1991,10(5):445-453
Examination of nascent globin peptides accumulatingin vitro during globin synthesis in rabbit reticulocyte lysates was carried out. A view was supported that nonrandom distribution of codons with different usage frequencies in mRNA may determine the messenger's translation kinetics. Regions of reduced translation of - and -globin polypeptide chains were localized, and the cotranslational protein-folding model suggested previously was substantiated. An active conjunction of synthesis and folding of proteins was proposed as one of the main destinations of a translation nonuniformity. 相似文献