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251.
252.
Intensely pigmented and spherical vesicles (anthocyanoplasts) were found in anthocyanin-containing cells of sweet potato (Ipomoea batatas) suspension cultures. Anthocyanin synthesis began to first occur 24–48 h after exposure to light, and then numerous small red vesicles were detected under a microscope. The frequency of anthocyanoplast-containing cells rapidly increased to finally about 80% of the total cultured cells after 5 days of irradiation. Fully developed anthocyanoplasts reached 10–15 m in diameter. On the other hand, neither anthocyanin synthesis nor development of anthocyanoplasts was induced in the dark-cultured cells. 2,4-D also inhibited anthocyanin synthesis and development of these vesicles. The results suggest that anthocyanoplasts might be a site of anthocyanin synthesis and/or accumulation.Abbreviation 2,4-D
2,4-dichlorophenoxyacetic acid 相似文献
253.
Tomoshiro Takeda Osamu Ueno Muneaki Samejima Takeshi Ohtani 《Journal of plant research》1985,98(4):393-411
Two hundred and twenty species of 38 genera in the Cyperaceae from Australia were examined for the possible occurrence of the C4 photosynthesis and the anatomical features of leaves and culms. The Kranz type of anatomy and the carbon isotope ratios typical of C4 plants were found in 84 species in the following six genera of four tribes belonging to subfamily Cyperoideae:Bulbostylis, Crosslandia, andFimbristylis (Fimbristylideae);Lipocarpha (Lipocarpheae);Cyperus (Cypereae);Rhynchospora (Rhynchosporeae). The anatomical observation revealed that the C4 species possessed any one of the three Kranz anatomical types found by previous investigators. It was suggested that in the Cyperaceae the C4 syndrome evolved independently within several taxa of the subfamily. The relative distribution of C3 and C4 species of the Cyperaceae in Australia was investigated by use of floristic data. It was recognized that the C4 species dominated in the northern part of the continent which was characterized by tropical and subtropical savannas and hot dry areas with summer rainfall, and the C3 species in the southern part, which contained temperate areas and mediterranean climatic areas with winter rainfall. 相似文献
254.
Gene structures of low-neurovirulent vaccinia virus LC16m0, LC16m8, and their Lister original (LO) strains 总被引:3,自引:0,他引:3
M Sugimoto A Yasuda K Miki M Morita K Suzuki N Uchida S Hashizume 《Microbiology and immunology》1985,29(5):421-428
Vaccinia viruses LC16m0 and LC16m8 are temperature-sensitive and low-neurovirulent variants derived from the Lister (Elstree) (LO) strain. Analyses of genome DNAs by digestion with restriction endonucleases and cross-hybridization of the digested fragments revealed that LC16m0 and LC16m8 possess a new XhoI site in addition to the 14 XhoI sites of LO. This new site is located at about 12 X 10(6) daltons from the right terminal end. There was no significant difference in the genome structures between the LC16 variants and LO except the new XhoI site and their terminal fragments which were not identified in LO owing to their heterogeneity. With HindIII digested fragments, there was no difference among the three viruses. This complete mapping raised the possibility that the putative gene responsible for temperature sensitivity and neurovirulence is located at the region of the XhoI site found in LC16m0 and LC16m8. 相似文献
255.
H Saito J Ozaki J Yasuda M Kurokawa T Tomita Y Okubo M Tanaka S Nakagawa 《Japanese journal of medical science & biology》1984,37(2):83-95
The utility of the Groupamatic MG50 system for quantitative expression of agglutination in terms of continuous response was studied. By use of the characteristics of the design of this system, in which the change in voltage reflects the degree of agglutination, a linear regression relationship between the log ratio of light flux obtained by transformation of the voltage and the log dilution factor of the serum was demonstrated. The availability of the parallel line assay method to the standardization of the blood grouping antisera was also described. 相似文献
256.
In an attempt to elucidate the relationship between phosphatidylinositol breakdown and alpha-adrenergic responses, effects of phosphatidic acid and phosphatidylinositol related metabolites on Ca2+ mobilization and glucose output in cultured hepatocytes were examined. Norepinephrine induced the net 45Ca2+ efflux from preloaded cells and stimulated glucose output via alpha-adrenergic receptor stimulation, whereas phosphatidic acid caused 45Ca2+ uptake to cells and did not stimulate glucose output. Myo-inositol-monophosphate, diglyceride and arachidonic acid, which are released by phosphatidylinositol breakdown, had no effect on 45Ca2+ efflux and glucose output in cells. These results suggest that phosphatidic acid and phosphatidylinositol related metabolites can not mimic the alpha-adrenergic actions in cultured hepatocytes. 相似文献
257.
Subhash Padhye Takeshi Kambara David N. Hendrickson Govindjee 《Photosynthesis research》1986,9(1-2):103-112
The recent model of Kambara and Govindjee for water oxidation [Kambara T. and Govindjee (1985) Proc. Natl. Acad. Sci. U.S.A., 82:6119–6123] has been extended in this paper by examining all the data in order to identify the most likely candidate for the redox-active ligand (RAL), suggested to operate between the water oxidizing complex (WOC) and Z, the electron donor to the reaction center P680. We have concluded that a very suitable candidate for RAL is the imidazole moiety of a histidine residue. The electrochemical data available on imidazole derivatives play heavily in this identification of RAL. Thus, we suggest that histidine might play the role of an electron mediator between the WOC and Z. A model of S-states in terms of their plausible chemical identity is presented here.Abbreviations J
electronic spin of ion
- P680
reaction center chlorophyll
- RAL
Redox active ligand
- Sn
state of the oxygen-evolving system
- WOC
water oxidation complex
- Z
electron donor to P680
Dedicated to Prof. L.N.M. Duysens on the occasion of his retirement 相似文献
258.
259.
Flavonoids in the leaves of twenty-eight species belonging to the Polygonaceae were studied. Thirty-three kinds of flavonoids
were isolated, and eighteen kinds were obtained as crystals. Quercetin glycosides were commonly found in the family. In the
quercetin glycosides, 3-O-rhamnoside was most frequently found: 3-O-glucuronide is also distributed widely. Myricetin glycosides were rare. Methylated flavonols were found in some species of
the sectionsEchinocaulon andPersicaria. Eleven kinds ofC-glycosylflavones were found in the present survey, andC-glycosylflavones were distributed in all species of the genusRheum and in almost all species of the section Tiniaria.Rumex Acetosella andPolygonum suffultum are exceptional, the former contains flavone glycoside and the latterC-glycosylflavones only, as main components. 相似文献
260.
Overproduction of Escherichia coli replication proteins by the use of runaway-replication plasmids. 总被引:12,自引:5,他引:7 下载免费PDF全文
A derivative of the runaway-replication plasmid was constructed. This plasmid, pSY343, has the gene for kanamycin resistance and single sites for EcoRI, BamHI, HindIII, KpnI, and XhoI that can be used as cloning sites without inactivating the kanamycin resistance gene or the replication genes. Three replication genes of Escherichia coli were cloned on the plasmid. The activity of dnaA, dnaZ, and ssb gene products were 200-, 90-, and 60-fold greater, respectively, in the cells containing these plasmids than in normal cells. 相似文献