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1.
F Stephen Perry 《BMJ (Clinical research ed.)》1998,317(7156):481
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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.
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M D Keppler M A Read P J Perry J O Trent T C Jenkins A P Reszka S Neidle K R Fox 《European journal of biochemistry》1999,263(3):817-825
We have used quantitative DNase I footprinting to measure the relative affinities of four disubstituted and two monosubstituted amidoanthraquinone compounds for intermolecular DNA triplexes, and have examined how the position of the attached base-functionalized substituents affects their ability to stabilize DNA triplexes. All four isomeric disubstituted derivatives examined stabilize DNA triplexes at micromolar or lower concentrations. Of the compounds studied the 2,7-disubstituted amidoanthraquinone displayed the greatest triplex affinity. The order of triplex affinity for the other disubstituted ligands decreases in the order 2,7 > 1,8 = 1,5 > 2,6, with the equivalent monosubstituted compounds being at least an order of magnitude less efficient. The 1,5-disubstituted derivative also shows some interaction with duplex DNA. These results have been confirmed by molecular modelling studies, which provide a rational basis for the structure-activity relationships. These suggest that, although all of the compounds bind through an intercalative mode, the 2,6, 2,7 and 1,5 disubstituted isomers bind with their two side groups occupying adjacent triplex grooves, in contrast with the 1,8 isomer which is positioned with both side groups in the same triplex groove. 相似文献
7.
Molecular Forms of Acetylcholinesterase and Butyrylcholinesterase in Human Plasma and Cerebrospinal Fluid 总被引:1,自引:0,他引:1
John R. Atack Elaine K. Perry James R. Bonham Robert H. Perry 《Journal of neurochemistry》1987,48(6):1845-1850
The measurement of cholinesterase activities in either plasma or cerebrospinal fluid (CSF) may ultimately prove to be relevant in the diagnosis of neurological and neuropsychiatric disorders. However, studies to date have examined only total enzyme activities. Therefore in the present study we have examined the distribution of the individual molecular forms of both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in plasma and CSF using sucrose density gradient centrifugation. Although the total activities of AChE were of the same order of magnitude in plasma and CSF, there was a considerable difference (120-500-fold) between total BChE activity in the CSF and the BChE-rich plasma. The analysis of the individual molecular forms revealed that the predominant molecular species of AChE and BChE in the CSF--both lumbar and ventricular--was the G4 form. The G4 form also constituted the majority of the plasma BChE activity and, on average, over half (56%) of the plasma AChE activity. The significance of the AChE and BChE molecular form compositions of both plasma and CSF and their possible relationship to pathological states are discussed. 相似文献
8.
Low-calcium-response, or Lcr, plasmids of yersiniae are known to promote an in vitro nutritional requirement for 2.5 mM Ca2+ at 37 degrees C which, if not fulfilled, results in cessation of growth with induction of virulence functions (Lcr+). The mechanism whereby Ca2+ regulates this metabolic shift is unknown. Radioactive Ca2+ was not actively accumulated by yersiniae but was excluded by an exit reaction analogous to those described for other bacteria. Nevertheless, cultivation at 37 degrees C with 0.1 mM Ca2+, a level insufficient to prevent restriction of cell division, promoted significantly more binding of the cation by Lcr+ organisms than by plasmid-deficient Lcr- mutants. According, Lcr+ yersiniae may possess unique ligands capable of recognizing Ca2+. 相似文献
9.
Electrophoretic and immunochemical study of the lipopolysaccharides produced by chemostat-grown Escherichia coli O157 总被引:3,自引:0,他引:3
Two chemically different O-polysaccharides, a low molecular mass form of LPS and core LPS produced by chemostat-grown E. coli O157, were analysed by SDS-PAGE, silver staining and immunoblotting. The reactivities of the different O-polysaccharides with antisera prepared against E. coli O157 grown in batch culture, Salmonella O30 or Brucella abortus were very similar, showing that the O-polysaccharides share at least some antigenic determinants. The reactions of the low molecular mass LPS with the antisera indicated it was semi-rough LPS having one repeat unit of the O-polysaccharide attached to core LPS. 相似文献
10.
Kinetics and specificity of T and B cell responses in relapsing experimental allergic encephalomyelitis 总被引:2,自引:0,他引:2
T and B cell responses to myelin basic protein (MBP) and its relevant peptide fragments were examined throughout the course of MBP-induced relapsing experimental allergic encephalomyelitis (REAE) in (SJL X PL)F1 mice. T cell reactivity, measured by the antigen-driven proliferation of lymph node T cells in vitro, was directed predominantly against the encephalitogenic MBP-P2 peptide (amino acids 1 to 37) at all stages of disease. Levels of responsiveness did not correlate with disease expression, but declined over time to a relapse level that was four- to sixfold lower than that observed during peak acute stage reactivity. Relapse responses were further distinguished by the detection of host I-E restrictions on Lyt-1+ T cell recognition of P2, P2 recognition by acute-stage T cells occurring solely in the context of host I-A molecules. These data imply an increase in the heterogeneity of relapse T cell responses to MBP to include clones restricted by additional class II glycoproteins. A role for additional CNS autoantigens in the stimulation of relapse T cells is also considered. Serum antibody responses to MBP or the P2 fragment fluctuated randomly throughout R-EAE when total antibody activity (IgM plus IgG) was measured. However, analysis of individual isotypes of IgG immunoglobulins revealed an apparent correlation between peak antigen-binding activity and disease expression which may reflect either an effector or regulatory role for humoral immunity in recurrent EAE. Patterns of early antibody reactivity also distinguished F1 mice that developed or failed to develop disease signs after immunization, the latter exhibiting a consistent drop in antigen-binding activity 4 to 5 days before the usual onset of acute-stage paralysis. The results are considered with regard to possible mechanisms of chronic disease regulation in an environment of functional T cell suppression. 相似文献