全文获取类型
收费全文 | 2081篇 |
免费 | 80篇 |
国内免费 | 20篇 |
出版年
2023年 | 13篇 |
2022年 | 23篇 |
2021年 | 20篇 |
2020年 | 28篇 |
2019年 | 48篇 |
2018年 | 51篇 |
2017年 | 37篇 |
2016年 | 30篇 |
2015年 | 32篇 |
2014年 | 44篇 |
2013年 | 94篇 |
2012年 | 32篇 |
2011年 | 33篇 |
2010年 | 37篇 |
2009年 | 68篇 |
2008年 | 60篇 |
2007年 | 54篇 |
2006年 | 68篇 |
2005年 | 59篇 |
2004年 | 60篇 |
2003年 | 59篇 |
2002年 | 53篇 |
2001年 | 47篇 |
2000年 | 40篇 |
1999年 | 33篇 |
1998年 | 30篇 |
1997年 | 38篇 |
1996年 | 31篇 |
1995年 | 33篇 |
1994年 | 37篇 |
1993年 | 44篇 |
1992年 | 51篇 |
1991年 | 47篇 |
1990年 | 46篇 |
1989年 | 55篇 |
1988年 | 41篇 |
1987年 | 47篇 |
1986年 | 47篇 |
1985年 | 75篇 |
1984年 | 68篇 |
1983年 | 52篇 |
1982年 | 83篇 |
1981年 | 61篇 |
1980年 | 40篇 |
1979年 | 30篇 |
1978年 | 26篇 |
1977年 | 20篇 |
1976年 | 24篇 |
1974年 | 8篇 |
1971年 | 5篇 |
排序方式: 共有2181条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
John S Schutzbach 《Glycoconjugate journal》1997,14(2):175-182
The enzymes in the dolichol pathway are membrane-proteins that utilize a combination of hydrophilic and extremely hydrophobic
substrates. The enzymes in this pathway that have been purified and characterized to any extent have either been shown to
be stabilized by mixed phospholipid/detergent micelles, or else require a lipid matrix for catalytic activity. Further understanding
of the mechanisms of these essential enzymes may require developing methods for the reconstitution of the glycosyltransferases
and their hydrophobic substrates in appropriate lipid matrices. Abbreviations: CHO, Chinese hamster ovary; Dol, dolichol;
DAG, diacylglycerol; DOPC, dioleolylphosphatidylcholine; DOPE, dioleolyphosphatidylethanolamine; ER, endoplasmic reticulum;
PC, phosphatidylcholine; PE, phosphatidylethanolamine; PG, phosphatidylglycerol; PI, phosphatidylinositol
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
6.
Bruce Cornell 《Journal of bioenergetics and biomembranes》1987,19(6):655-676
Gramicidin A forms ion-conducting channels which can traverse the hydrocarbon core of lipid bilayer membranes. The structures formed by gramicidin A are among the best characterized of all membrane-bound polypeptides or proteins. In this review a brief summary is given of the occurrence, conformation, and synthesis of gramicidin A, and of its use as a model for ion transport and the interaction of proteins and lipids in biological membranes. 相似文献
7.
A. Coulombe H. Duclohier E. Coraboeuf N. Touzet 《European biophysics journal : EBJ》1987,14(3):155-162
Large conductance channels were observed in the membrane of cultured cardiac cells of newborn rats studied with the patch-clamp technique in cell-attached and inside-out configurations. These channels were observed in 4% of the patches. In the cell-attached configuration they exhibited outward rectification and partial inactivation. In the inside-out configuration no rectification occurred but inactivation was present, mainly during hyperpolarizations. Two channels with large single unit conductances (400–450 pS) and one with a smaller conductance (200–250 pS) were frequently observed in the same patch. The two large channels generally had different kinetics. Under steady-state conditions the opening probability of the faster channel appeared to be voltage-independent. The slower channel was activated by depolarization. In asymmetrical solutions the permeability ratios P
Na/P
Cl were 0.03 and 0.24 for the larger and smaller channels, respectively; corresponding values for P
Ba/P
Cl were 0.04 and 0.09. It is proposed that in cardiac membranes the chloride permeability system is composed of widely dispersed microclusters forming grouped channels of different types and sizes. 相似文献
8.
R. E. Dale 《European biophysics journal : EBJ》1987,14(3):179-193
The effects of the fact that the laser sources typically used in fluorescence photobleaching recovery (FPR) experiments in the most commonly employed in-line microscope imaging geometries, are highly linearly polarized, are examined in some detail. The implications of the results, in particular for the interpretation of FPR data in complex cell membrane systems in terms of laterally mobile and immobile sub-populations of the labelled molecular species of concern, are discussed. Methods of experimentally eliminating the potentially major rotational diffusion-based artifacts, different from those appropriate to three-dimensional (solution or suspension) systems which require other than in-line geometries, are delineated.Abbreviations FPR
fluorescence photobleaching recovery
- FRAP
fluorescence recovery after photobleaching
- 2- and 3-D
two- and three-dimensional 相似文献
9.
The translational diffusion of pyrene, pyrene butyric acid and pyrene decanoic acid has been determined in phosphatidylcholine bilayers of different chain length and under pressure up to 200 bars. In the liquid crystalline phase and at a given temperature the diffusion decreases with increasing chain length. At a constant reduced temperature, T
red (about 10 K above the transition temperature), long chain lipids exhibit the fastest diffusion which is in disagreement with hydrodynamic models but favours free volume models for diffusion in lipid bilayers. The volume of activation, V
act, calculated from the decrease of the diffusion coefficient with pressure, ln D/P, depends on lipid chain length. V
act decreases with decreasing lipid chain length at a given temperature, T=65°C, and increases at the reduced temperature. These results are again in agreement with the dependence of the diffusion on lipid chain length and therefore with the free volume model.Abbreviations DLPC
Dilauroylphosphatidylcholine
- DMPC
Dimyristoylphosphatidylcholine
- DPPC
Dipalmitoylphosphatidylcholine
- DSPC
Distearoylphosphatidylcholine
- LUV
Large unilamellar vesicles
- SUV
Small unilamellar vesicles
- Tris
Tris(hydroxymethyl)aminomethan 相似文献
10.
Solubilisation of a Glutamate Binding Protein from Rat Brain 总被引:2,自引:2,他引:0
Rat brain synaptic plasma membranes were solubilised in either 1% Triton X-100 or potassium cholate and subjected to batch affinity adsorption on L-glutamate/bovine serum albumin reticulated glass fibre. The fibre was extensively washed, and bound proteins eluted with 0.1 mM L-glutamate in 0.1% detergent, followed by repeated dialysis to remove the glutamate from the eluted proteins. Aliquots of the dialysed extracts were assayed for L-[3H]glutamate binding activity in the presence or absence of 0.1 mM unlabelled L-glutamate (to define displaceable binding). Incubations were conducted at room temperature and terminated by rapid filtration through nitrocellulose membranes. Binding to solubilised fractions could be detected only following affinity chromatography. Binding was saturable and of relatively low affinity: KD = 1.0 and 1.8 microM for Triton X-100 and cholate extracts, respectively. The density of binding sites was remarkably high: approximately 18 nmol/mg protein for Triton X-100-solubilised preparations, and usually double this when cholate was employed. Analysis of structural requirements for inhibition of binding revealed that only a very restricted number of compounds were effective, i.e., L-glutamate, L-aspartate, and sulphur-containing amino acids. Binding was not inhibited significantly by any of the selective excitatory amino acid receptor agonists--quisqualate, N-methyl-D-aspartate, or kainate. The implication from this study is that the glutamate binding protein is similar if not identical to one previously isolated and probably is not related to the pharmacologically defined postsynaptic receptor subtypes, unless solubilisation of synaptic membranes resulted in major alterations to binding site characteristics. Since solubilisation with Triton X-100 is known to preserve synaptic junctional complexes, it seems likely that the origin of the glutamate binding protein may be extrajunctional, although its functional role is unknown. 相似文献