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71.
K Ichikawa K Hashizume M Kobayashi Y Nishii A Sakurai T Takeda S Suzuki T Yamada 《Endocrinologia japonica》1992,39(2):203-207
Human beta thyroid hormone receptor (c-erb A beta protein) produced by an Escherichia coli expression system was purified by sequential column chromatography followed by electroelution from an electrophoresis gel and an antibody was prepared. The antibody recognized a 56 kDa protein band in a partially purified rat hepatic nuclear thyroid hormone receptor fraction on Western blotting. Although multiple bands appeared on Western blotting of crude rat hepatic receptor preparations, a 56 kDa band was the most prominent and preadsorption of the antibody by purified c-erb A protein resulted in almost complete disappearance of the 56 kDa band, indicating that the 56 kDa band was formed by a specific antigen-antibody interaction. Furthermore, the 56 kDa protein appeared to co-elute with 3, 5, 3'-triiodo-L-thyronine binding activity in hydroxylapatite, Sephacryl S-200, and DNA-cellulose column chromatography of rat hepatic nuclear receptor, and sequential column purification resulted in selective enrichment of the 56 kDa band. These results suggest that the 56 kDa protein may be the major component of the rat hepatic thyroid hormone receptor. 相似文献
72.
The disaccharide trehalose extensively exists in anhydrobiotic organism and is considered to play an important role in preserving the integrity of biomembrane. However, the preserving mechanism remains unclear. In this report, we examine the hydration abilities of trehalose and several oligosaccharides composed of alpha-D-glucopyranosyl residues. The unfrozen water fraction per molecule was determined from differential scanning calorimetry measurements of their aqueous solutions. Further, the NMR relaxation time of the natural abundance 17O of water is measured for several saccharide solutions. These results indicate that trehalose has the highest hydration ability among the saccharides studied. In other words, trehalose can effectively lower the mobility of water molecules hydrogen-bonded with saccharides. It is thus reasonable that, among the disaccharides studied, trehalose exhibits the maximum stabilizing effect on the bilayer structure of lipid whose acyl chains are bonded with each other by the apolar interaction, because the apolar interaction is strengthened with the stabilization of the surrounding water structure. 相似文献
73.
T Sakurai S Kimura M Nakano H Kimura 《Biochemical and biophysical research communications》1991,177(1):433-439
This is the first observation for contributing to the glycation of low density lipoprotein (LDL) to oxidative modification of its own lipids and protein. Human plasma LDL was glycated by incubation with glucose (G-LDL). Glucose incorporated into apoprotein B was approximately 10 mol/mol of apoprotein (2.8% modification of lysine residues) and 84% of G-LDL was adsorbed on phenylboronate affinity column. G-LDL incubated with Fe3+ for 4 h caused a significantly higher level of lipid peroxidation than U-LDL (untreated with glucose), and a higher molecular weight protein was observed in apoprotein B on SDS-polyacrylamide gel electrophoresis (SDS-PAGE), increasing with incubation period. Corresponding to change on SDS-PAGE, G-LDL exposed to Fe3+ moved faster than G-LDL per se or U-LDL to anode on agarose gel electrophoresis. The higher the Fe3+ concentration, the more lipid peroxidation was caused. Alpha-tocopherol or probucol suppressed the lipid peroxidation of G-LDL exposed to Fe3+. 相似文献
74.
A specific protein, p92, detected in flat revertants derived from NIH/3T3 transformed by human activated c-Ha-ras oncogene 总被引:4,自引:0,他引:4
H Fujita H Suzuki N Kuzumaki L Müllauer Y Ogiso A Oda K Ebisawa T Sakurai Y Nonomura S Kijimoto-Ochiai 《Experimental cell research》1990,186(1):115-121
Total proteins from a mouse embryo fibroblast cell line NIH/3T3, NIH/3T3 cells transformed by human activated c-Ha-ras (EJ-ras) oncogene (EJ-NIH/3T3), and the two flat revertant cell lines, R1 and R2, were analyzed by two-dimensional gel electrophoresis (IEF and NEPHGE). Several hundred polypeptides were resolved as seen by silver staining. Common alterations in four polypeptide spots were observed in the revertants when compared with NIH/3T3 and EJ-NIH/3T3 cells. In these alterations, a new polypeptide spot p92-5.7 (designated by molecular weight x 10(-3) and pI) was detected only in the revertants and not in NIH/3T3 and EJ-NIH/3T3 cells. Furthermore, the expression level of p92-5.7 seemed to be associated with the flat morphology and the reduced tumorigenicity of the revertants. Polypeptide p92-5.7 was also not detected in the total proteins extracted from BALB/3T3 cells, NIH Swiss mouse primary embryo fibroblasts, NRK (normal rat kidney) cells, and L6 (rat myoblast). Subcellular fractionation of total protein from R1 cells revealed that the p92-5.7 was present in the cytosol. Western blot analysis using an anti-gelsolin antibody demonstrated that the p92-5.7 might be a variant form of gelsolin which is thought to be an actin regulatory protein or a gelsolin-like polypeptide. These results may suggest that the expression of p92-5.7 detected only in the revertants is associated, at least in part, with the reversion. This may be the first demonstration of specific protein expression in the flat revertants. 相似文献
75.
O2- generation and lipid peroxidation during the oxidation of a glycated polypeptide, glycated polylysine, in the presence of iron-ADP 总被引:5,自引:0,他引:5
Oxidation of glycated polylysine, a model compound of glycated protein, caused O2- production even at physiological pH, which could be accelerated by Fe3(+)-ADP. An enediol structure in glycated polylysine and related compounds, which could be confirmed by I2 uptake, was related to their oxidizability. Glycated polylysine was easily coordinated with Fe3+ even in the presence of phosphate at pH 7.4 and the formation of the iron complex was prevented by desferrioxamine. The exposure of unsaturated phospholipid liposomes to glycated polylysine-Fe3(+)-ADP system caused the production of a thiobarbituric acid-reacting substance, which was completely inhibited by 5 microM alpha-tocopherol or 150 microM desferrioxamine and slightly by 0.5 microM SOD. Catalase (20 micrograms/ml) and 10 mM sodium-benzoate did not affect the iron-glycated polylysine-induced lipid peroxidation, indicating no participation of an OH. in this reaction. A ferrous ion-coordinated glycated polylysine may act as an initiator of phospholipid peroxidation in the presence of oxygen. A possible mechanism of the iron-glycated polylysine-induced lipid peroxidation was discussed. 相似文献
76.
77.
ß-Naphthyl di-, tri- or tetraphosphate inhibits photophosphorylationof spinach chloroplasts competitively with ADP, whereas ß-naphthylmonophosphate inhibits it competitively with Pi. The apparentKi of ß-naphthyl diphosphate for the ADP site was300 µM and that of ß-naphthyl monophosphatefor the Pi site was 1.45 mM. At 10 mM, both of these two organicphosphates inhibited photophosphorylation more than 90%. Noneof the above four ß-naphthyl phosphates were phosphorylatedby chloroplasts. ß-Naphthyl di-, tri- or tetraphosphateinhibits ATPase activity of isolated chloroplast coupling factor1 (CF1) (EC 3.6.1.3
[EC]
) and light-triggered ATPase activity ofchloroplasts competitively with ATP, whereas ß-naphthylmonophosphate acts non-competitively. None of the four ß-naphthylphosphates were hydrolyzed by these two ATPase activities. Atconcentrations equal to ADP or ATP, ß-naphthyl di-,tri- or tetraphosphate inhibited these three reactions in theorder; ATPase of isolated CF1> photophosphorylation>light-triggeredATPase of chloroplasts. The results suggest that the effect of the monophosphate isprincipally on the Pi site(s) and that of the di-, tri- or tetraphosphateis on the adenine nucleotide site(s) on the active center ofCF1.
1Part of this work was reported at the 1979 Annual Meeting ofthe Japanese Society of Plant Physiologists (Nagoya, April 7,1979) and the 52nd Annual Meeting of the Japanese BiochemicalSociety (Tokyo, October 7, 1979). This work was supported inpart by Grants-in-Aid for Scientific Research from the Ministryof Education, Science and Culture, Japan (311808 and 311909). (Received November 14, 1979; ) 相似文献
78.
Yuji Kamiya Akira Sakurai Nobutaka Takahashi 《Biochemical and biophysical research communications》1980,94(3):855-860
Rhodotorucine which induces mating tube formation of cells in is metabolized rapidly by cells. By use of labeled rhodotorucine , the degradation was found to be proteolytic. Two peptide fragments Tyr-Pro-Glu-Ile-Ser-Trp-Thr-Arg and Asn-Gly-Cys(S-farnesyl) were identified as the metabolites. Proteolysis of the pheromone mainly occurred on the cell surface. Culture filtrate of cells at log phase did not metabolize rhodotorucine . 相似文献
79.
M Iida H Sakurai K Matsuhashi T Yanaihara 《Zeitschrift für allgemeine Mikrobiologie》1979,19(8):553-556
[14-14C]16 alpha-Hydroxy-C-18- and C-19-steroid hormones were obtained in good yields by microbiological hydroxylation of correspondingly labelled steroids by Streptomyces roseochromogenes NRRL B-1233. Trace quantities of the labelled substrates were incubated on a rotary shaker (220 rpm) at 27 degrees C. The radioactive products were chromatographically separated, identified and the radiochemical purity was established by isotopic dilution analysis. The specific activities of 16 alpha-hydroxy-steroids obtained were assumed to be the same as those of the substrates, namely, 57.5 mCi/mmole for 16 alpha-hydroxy-4-androstene-3,17-dione, 57.5 mCi/mmole for 5-androstene-3 beta,16 alpha,17 beta-triol, 57.5 mCi/mmole for 16 alpha-hydroxy-dehydroepiandrosterone, 55.7 mCi/mmole for 16 alpha-hydroxy-estrone, and 57.5 mCi/mmole for 16 alpha-hydroxy-testosterone. 相似文献
80.
K Furuse T Sakurai A Hirashima M Katsuki A Ando I Watanabe 《Applied microbiology》1978,35(6):995-1002
We investigated the distribution of ribonucleic acid (RNA) coliphages in the Philippines, Singapore, Indonesia, India, and Thailand by collecting sewage samples from domestic drainage in November 1976. Of the 221 samples collected from domestic drainage, 50 contained RNA phages (52 strains). By serological analysis, 46 of the 52 strains were found to belong to group III. It can thus be said that the most prevalent RNA phages in Southeast Asia (at least, in the Philippines, Singapore, and Indonesia) were group III phages. Investigations of sewage samples collected from domestic drainage in Japan indicate that the most prevalent RNA phages in mainland Japan (north of Kyushu) are group II phages, whereas group III phages are predominant in the southern part of Japan (south of Amamiohshima Island). We therefore propose a borderline between Kyushu and Amamiohshima Island for the geographical distribution of RNA coliphages in the domestic drainage of South and East Asia. Moreover, one strain (ID2) was inactivated to some extent with the antisera of four groups of RNA phages. This is thought to be significant from the evolutionary viewpoint. 相似文献