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121.
GTPase from rod outer segments: characterization by photoaffinity labeling and tryptic peptide mapping 总被引:2,自引:0,他引:2
D J Takemoto B E Haley J Hansen O Pinkett L J Takemoto 《Biochemical and biophysical research communications》1981,102(1):341-347
The photoaffinity label [γ-32P]8-N3GTP has been used to identify GTP-binding components in highly purified preparations of GTPase from bovine rod outer segments. These preparations contain two major polypeptides of 37,000 and 39,000 daltons. In the presence of photolyzing radiation, [γ-32P]8-N3GTP is covalently attached to the 37,000 dalton polypeptide. Tryptic peptide mapping of this polypeptide indicates that it is highly related to the 39,000 dalton species that has been previously identified as a GTP-binding component. 相似文献
122.
Separation of a variety of purine bases, which include 7-methyl derivatives, was studied by using polyethyleneimine-coated silicagel which bound hypoxanthine, cytosine or guanine moieties. The separation behavior seems to be related to the interaction of imidazole part of purine derivatives with the resins through hydrogen bonding. 相似文献
123.
Isao Ueyama Yasuhiko Uesugi Chōjirō Tomizawa Toshinobu Murai 《Bioscience, biotechnology, and biochemistry》2013,77(7):1543-1551
Metabolism and residual fate of O-ethyl S,S-diphenyl phosphorodithiolate (Hinosan®) applied on rice plant was examined by using 35S-labeled or 32P-labeled compound. Ion exchange chromatography, thin-layer chromatography and gas-liquid chromatography with flame thermionic detector or flame photometric detector were applied for identification of water soluble and toluene soluble metabolites of Hinosan. Degradation of Hinosan at the initial stage of metabolism was mainly the cleavage of P-S linkage, and a large portion of phenyl dihydrogen phosphorothiolate and a minor portion of O-ethyl S-phenyl hydrogen phosphorothiolate were found as water soluble metabolites. Phenylthio radical released on the production of the above mentioned metabolites was recovered as diphenyl disulfide, which was finally converted to sulfuric acid through benzenesulfonic acid. Triphenyl phosphorotrithiolate and O,O-diethyl S-phenyl phosphorothiolate were produced by transesterification between molecules of Hinosan at the initial stage of metabolism. Examination of metabolites in rice grains showed that sulfur and phosphorus atoms in Hinosan were incorporated into neutral or cationic substances probably after several steps of chemical transformation. 相似文献
124.
125.
Identification of Chitinase and Osmotin-Like Protein as Actin-Binding Proteins in Suspension-Cultured Potato Cells 总被引:3,自引:0,他引:3
Takemoto Daigo; Furuse Katsumi; Doke Noriyuki; Kazuhito Kawakita 《Plant & cell physiology》1997,38(4):441-448
Cytoplasmic aggregation is an early resistance-associated eventthat is observed in potato tissues either after penetrationof an incompatible race of Phytophthora infestans, the potatolate blight fungus, or after treatment with hyphal wall components(HWC) prepared from P. infestans. In potato cells in suspensionculture, the number of cells with cytoplasmic aggregation increasedupon treatment with HWC, but such an increase was suppressedby treatment with cytochalasin D prior to treatment with HWC.This result suggested that cytoplasmic aggregation in culturedpotato cells might be connected with the association of actinfilaments. To identify the molecular basis of cytoplasmic aggregation,we purified actin and actin-related proteins by affinity chromatographyon a column of immobilized DNase I from cultured potato cellsand isolated proteins of 43 kDa, 32 kDa and 22 kDa. Analysisof the amino-terminal amino acid sequences indicated that the43 kDa, 32 kDa and 22 kDa proteins were potato actin, basicchitinase and osmotin-like protein, respectively. This conclusionwas supported by the results of Western blotting analysis ofthe 43 kDa and 32 kDa proteins with antibodies against actinand basic chitinase. Binding analysis with actin coupled toactin-specific antibodies and biotinylated actin suggested thatthe 32 kDa and 22 kDa proteins had actin-binding activity. Inaddition, examination of biomolecular interactions using anoptical biosensor confirmed the binding of chitinase to actin.These results imply the possibility that basic chitinase andosmotin-like protein might be involved in cytoplasmic aggregation,hereby participating in the potato cell's defense against attackby pathogen. (Received June 11, 1996; Accepted January 27, 1997) 相似文献
126.
Hidemitsu Kitamura Nobuko Takemoto Morimichi Mizuno Yoshinori Kuboki Nobuo Sakairi Norio Nishi 《International journal of biological macromolecules》1997,21(4):337-340
Phase-contrast and fluorescence microscopic observation showed that DNA added in the cell-culture medium for fibroblasts localized just on the surface of fibroblasts. The DNA bound to fibroblasts was found to be eluted by treating with collagenase. The suppression for the proliferation of fibroblasts by external DNA was confirmed with microscopic observation for the cells cultured in the presence and absence of DNA. Proliferation of the cells decreased from 412 to 155% by the addition of DNA. These results indicate that DNA has an affinity for collagen, the most major extracellular-matrix produced by fibroblasts, and suppresses the growth of fibroblasts. 相似文献
127.
Perrottetianal A and perrottetianal B, two new diterpene dialdehydes and a new ent-labdane-type diterpene diol have been isolated from the liverwort Porella perrottetiana and their structures have been elucidated by the chemical and spectral evidence. 相似文献
128.
Yoshinori Asakawa Masao Toyota Tsunematsu Takemoto Claude Suire 《Phytochemistry》1979,18(8):1349-1353
Three new pinguisane-type sesquiterpenes, pinguisanin, pinguisanolide and β-pinguisenediol, together with the previously known deoxopinguisone, have been isolated from a European liverwort, Porella platyphylla, and their structures have been established by the spectral evidence and some chemical transformations. 相似文献
129.
220-MHz NMR spectra of various poly (N-alkylamino acid)s are investigated. Spectra of polysarcosine recorded in various solvents showed fine splittings of the methyl and methylene bands. Comparing the spectrum with that of its model compound, the fine structure of the methyl band of polysarcosine was assigned to four dyad sequences of the cis–trans isomeric state of the main chain amide bonds. Also the methylene band was roughly divided into cis and trans bands. From the temperature dependence of the spectra of polysarcosine, a double coalescence phenomenon was observed, in which the four dyad peaks coalesced into two peaks corresponding to cis and trans, then the two peaks coalesced into one peak. Further, the approximate value of the free energy for the internal rotation of the main chain amide bond was estimated. NMR spectra of various poly(N-alkylglycine)s in methylene chloride solution were also obtained. From the comparsion of their methylene bands, the introduction of the bulky N-alkyl groups was found to increase the cis content of the amide bond. 相似文献
130.
J Takemoto 《Archives of biochemistry and biophysics》1974,163(2):515-520
Glycogen phosphorylase in cell-free extracts of Neurospora crassa is activated 10- to 15-fold by incubation with MgATP2?. When the MgATP2? is removed, the active form (a form) reverts to the inactive form (b form). The inactivation requires Mg2+ and is inhibited by NaF. The results confirm that Neurospora crassa glycogen phosphorylase exists in two interconvertible forms and strongly suggests that the interconversion is catalyzed by a kinase and phosphatase. The a form was partially purified. The enzyme has a molecular weight of 320,000. Uridine diphosphate glucose is a linear competitive inhibitor with respect to glucose-1-phosphate and a linear non-competitive inhibitor with respect to glycogen. Glucose-6-phosphate is a hyperbolic (partial) noncompetitive inhibitor with respect to all substrates in both directions. The b form of the enzyme in crude cell-free extracts is stimulated 2- to 3-fold by 5′-AMP. As the b form is purified, the 5′-AMP activation is diminished. The molecular weight of the partially purified “b” form was also 320,000. 相似文献