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51.
M Hiramatsu M Kashimata N Minami A Sato M Murayama N Minami 《Biochemistry international》1988,17(2):311-317
Castration of adult male mice caused a marked reduction in the amount of immunoreactive epidermal growth factor (EGF) in the ventral prostate, and the treatment of such castrated mice with testosterone increased the EGF level significantly. Gel filtration of prostate extract showed that the immunoreactive EGF in the prostate had the same molecular weight (6,045) as the submandibular gland EGF. Moreover, its isoelectric point (pH 4.5) was almost similar to that (pH 4.55) of the submandibular gland peptide. These results suggest that under the control of androgens, mouse ventral prostate synthesizes EGF structurally and functionally identical to the submandibular gland EGF. 相似文献
52.
Characterization of Microtubule-Associated Protein 2 from Mouse Brain and Its Localization in the Cerebellar Cortex 总被引:3,自引:2,他引:1
Michio Niinobe Nobuaki Maeda Hidetoshi Ino Katsuhiko Mikoshiba 《Journal of neurochemistry》1988,51(4):1132-1139
Microtubule-associated protein (MAP) 2 was purified from the microtubule fraction of mouse brain by heat treatment and BioGel A-5m gel filtration. The purified preparation showed a single protein band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis using both a gradient gel (3.75-12.5%) and a low-percentage gel (5%), a finding indicating that MAP2B was absent under the conditions used. Amino acid analysis revealed that mouse MAP2 was an acidic protein with an isoelectric point (pI 4.5) and amino acid composition similar to those of porcine brain MAP2. Immunoblot analysis indicated that the antigens that reacted with MAP2 antiserum were present in large quantities in mouse brain. However, we also found a weak reaction in various tissues other than brain, and the major antigens involved were recognized to be common molecular species with the same molecular mass, 162 and 170 kilodaltons. Using antiserum against mouse brain MAP2, the developmental localization patterns of MAP2 in the mouse cerebellar cortex were studied by immunohistochemistry. MAP2 was mainly localized in the neuronal cells throughout development, with the expression in Purkinje cell dendrites being especially remarkable in the growth of arborization from postnatal day 3 to day 20. At the mature stage, the reaction was strong in the dendritic tree but very weak in the proximal dendrites and cell bodies. 相似文献
53.
Sachiko Aono Hiroshi Sato Reiji Semba Shigeo Kashiwamata Kanefusa Kato † Lawrence F. Eng† 《Journal of neurochemistry》1988,50(3):717-721
The behavior of marker proteins of glial cells [alpha-enolase, beta-S100 protein, and glial fibrillary acidic protein (GFAP)] was investigated quantitatively by using enzyme immunoassay systems during the development of cerebellar hypoplasia in jaundiced Gunn rats. A neuronal marker protein, gamma-enolase, was also measured as a reference. At postnatal day 8 corresponding to the early stage of cerebellar damage, the amount of beta-S100 on a protein basis was significantly higher in jaundiced homozygotes (jj) than in control nonjaundiced heterozygotes (j+), whereas no differences in alpha- and gamma-enolases and GFAP were observed between the two groups of rats. At days 15 and 30, which correspond, respectively, to the advanced and late stages of cerebellar damage, the three glial proteins, especially GFAP, were higher and the neuronal protein was lower in the jj rat cerebellum than in the control. These results are consistent with the reported histological observations that neuronal cells are vulnerable and damaged by bilirubin, whereas glial cells seem to be less sensitive. On the other hand, the amounts of beta-S100 and alpha-enolase per cerebellum were significantly lower in jj rats at days 15 and 30, as in the case of gamma-enolase, whereas that of GFAP remained at the same level as the control at day 15 and showed a slight but significant decrease at day 30. The possibility is suggested that beta-S100 and GFAP may be available as biochemical indicators of glial cells, especially in the early and advanced stages of cerebellar damage, respectively, but that alpha-enolase is less available. 相似文献
54.
The hydrophobicity of the nontransformed and transformed androgen receptor from rat submandibular gland and heat shock protein 90 (hsp90) from rat submandibular gland and liver was characterized by using high-performance hydrophobic-interaction chromatography on TSK gel Ether-5PW. In the absence of molybdate, cytosol [3H]R1881-androgen receptor complexes were mainly eluted in the 1.3 M region (Peak 1) with a small peak in the 0.8 M region (Peak 2) of a descending salt gradient (2 to 0 M) of ammonium sulfate. In the presence of molybdate, Peak 2 was predominant. When labeled-cytosol was applied after being heated at 25 degrees C for 30 min, a third peak (Peak 3) at around 0.64 M ammonium sulfate was newly observed. Peaks 2 and 3 were observed, while Peak 1 completely disappeared with the labeled-cytosol precipitated at 40% saturated ammonium sulfate. The Stokes radius of Peak 1 was 7 nm, and of Peak 2 was 8 nm. Both peaks were retained poorly by DNA-cellulose but bound rather well to DEAE-cellulose. These results suggest that these two peaks represent the nontransformed receptor, indicating that there are isoforms of the nontransformed androgen receptor which are distinguished by their hydrophobic properties and Stokes radii. Peak 3 had a Stokes radius of 5 nm and preferentially bound to DNA-cellulose, suggesting that this peak corresponds to the transformed receptor. These results indicated that the transformation of the androgen receptor accompanies the enrichment of the hydrophobicity of the receptor molecule. Hsp90 purified from rat livers and hsp90 in the cytosol both from livers and submandibular glands were eluted from Ether-5PW at 0.8 M ammonium sulfate, at almost the same position as Peak 2. This finding suggests that the enrichment of hydrophobicity on transformation is due to dissociation of hsp90 from the nontransformed androgen receptor. 相似文献
55.
The possibility of involvement of calcium ions in the hatching of Schistosoma mansoni eggs in water is described. The hatching of S. mansoni eggs under low osmotic pressure was partially inhibited by EGTA (5 mM), lanthanum chloride (1-5 mM), and ruthenium red (0.1-1 mM). The reagents used in these experiments were not toxic to the eggs however, because miracidia hatched normally when the reagents were removed. 相似文献
56.
The effects of medicinal plants on the mutagenicity of benzo[a]pyrene were studied with Salmonella typhimurium tester strains. The chosen medicinal plants are very frequently used as Chinese herbal medicines. Each medicinal plant was extracted with hot water, which is similar to the method used in Chinese medicinal treatment. Cinnamomi cortex, Rhei rhizoma, Scutellariae radix and Rehmanniae radix were found to decrease the mutagenic activity of benzo[a]pyrene. Atractylodis rhizoma also reduced the mutagenicity of benzo[a]pyrene, but this was not certain, because it showed a killing effect on the cell survival test. Bupleuri radix and Aurantii nobilis pericarpium had an enhancing effect, but then neither of these extracts is itself mutagenic. Each medicinal plant extract showed a different effect on the mutagenicity of benzo[a]pyrene. These effects were classified into 5 types: (I) decreasing effect, (II) killing effect, (III) enhancing effect, (IV) enhancing and decreasing effect and (V) inactive. 相似文献
57.
Yazaki Yoshiaki; Maki Kazutoshi; Sato Tetsuya; Ohta Eiji; Sakata Makoto 《Plant & cell physiology》1988,29(8):1417-1422
The intracellular K+ concentration and its change in mung bean[Vigna mungo (L.) Hepper] root tips were investigated non-invasivelywith 39K nuclear magnetic resonance spectroscopy using a membraneimpermeable shift reagent, dysprosium (III) tripolyphosphate[Dy(PPPi)72]. The K+ resonance was shifted to highermagnetic field in proportion to the concentration of the shiftreagent. In addition to a reference capillary peak for measuringthe K+ concentration, two well-resolved peaks (intra- and extracellularK+ resonances) were observed in the 39K NMR spectra of mungbean root tips. The intracellular K+ concentration was determinedto be 41 mM, which was similar to the value obtained by flamephotometry. When 20 mM KCl was added to the external medium,the intensity of the intracellular K+ resonance gradually increasedand the net K+ uptake rate was calculated to be 4.1 micromolesper gram fresh weight per hour. After removal of KCl from theperfusion medium, the intracellular K+ concentration considerablydecreased. With 31P NMR method, 2.5 mM Dy(PPPj)712 and20 mM KCl had little effect on the ATP level in the cells. Wehave indicated that the 39K NMR method can be used to determinethe K+ levels and net fluxes of the K+ transport in perfusedroot tips successively. (Received April 6, 1988; Accepted September 29, 1988) 相似文献
58.
Autocrine activities of basic fibroblast growth factor: regulation of endothelial cell movement, plasminogen activator synthesis, and DNA synthesis 总被引:63,自引:25,他引:38
We have found that the spontaneous migration of bovine aortic endothelial cells from the edge of a denuded area in a confluent monolayer is dependent upon the release of endogenous basic fibroblast growth factor (bFGF). Cell movement is blocked by purified polyclonal rabbit IgG to bFGF as well as affinity purified anti-bFGF IgG and anti-bFGF F(ab')2 fragments. The inhibitory effect of the immunoglobulins is dependent upon antibody concentration, is reversible, is overcome by the addition of recombinant bFGF, and is removed by affinity chromatography of the antiserum through a column of bFGF-Sepharose. Cell movement is also reversibly inhibited by the addition of protamine sulfate and suramin; two agents reported to block bFGF binding to its receptor. The addition of recombinant bFGF to wounded monolayers accelerates the movement of cells into the denuded area. Transforming growth factor beta which has been shown to antagonize several other effects of bFGF also inhibits cell movement. The anti-bFGF IgG prevents the movement of bovine capillary endothelial cells, BHK-21, NIH 3T3, and human skin fibroblasts into a denuded area. Antibodies to bFGF, as well as suramin and protamine sulfate also suppress the basal levels of plasminogen activator and DNA synthesis in bovine aortic endothelial cells. 相似文献
59.
The active metabolite of vitamin D3, 1 alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3), inhibited morphologic and enzymatic expression during differentiation of preadipocyte to adipocyte. In the presence of approximately 6.4-20 X 10(-10) M 1,25(OH)2D3, the triacylglycerol accumulation was only 50% of that of fully differentiated control cells. High-affinity binding sites for 1,25-dihydroxyvitamin D3 were detected in two preadipose cell lines. The 1,25(OH)2D3 binding component sediments at 3.3 S in 4-24% (w/v) sucrose gradients prepared in hypertonic buffer. Binding assay revealed that Nmax was 70 fmol/mg protein and 90 fmol/mg protein, and Kd value was 170 pM and 37 pM in cell lines ST 13 and 3T3 L1, respectively. We also found that differentiated adipocytes did not contain specific receptors for 1,25(OH)2D3. 1,25(OH)2D3, 1(OH)D3, 24,25(OH)2D3, and 24(OH)D3 all suppressed differentiation of preadipocytes to adipocytes, and the dose required closely reflected the affinities of the various metabolites and the synthetic derivative for 1,25(OH)2D3 receptor. It is suggested that the action of vitamin D3 on preadipocyte differentiation may result from a receptor-mediated event. 相似文献