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991.
Parvo-like virus, which was designated as “Ina-flacherie virus (Ina-FV),” was isolated from the silkworm, Bombyx mori, and the properties of its DNA were characterized. Purified Ina-FV had a diameter of 22 ± 0.5 nm and a sedimentation coefficient of 102 S. On density gradient separation in CsCl, particles were found at densities of 1.40 and 1.45 g/ml. The DNA content of Ina-FV was 28 ± 2%. The DNA in low-salt buffer possessed properties typical of a single-stranded (ss) molecule. Double-stranded (ds) DNA was extracted under conditions of appropriate high salt and elevated temperature. Electron microscopical examination revealed that the ds DNA was composed of linear molecules with an average length of 1.7 μm and other less well-defined structures. The linear ds molecule had a molecular weight of about 3.4 × 106 determined by electron microscopy (EM) and agarose gel electrophoresis. When the ds DNA was alkali-denatured and examined in an EM, linear ss molecules with approximate length of 1.7 μm were observed, indicating that the linear ds molecule was formed from the annealing of the linear ss molecules of unit length. These data suggest that Ina-FV is closely related to members of the densovirus subgroup. 相似文献
992.
Yoshinori Asakawa Hiroshi Inoue Masao Toyota Tsunematsu Takemoto 《Phytochemistry》1980,19(12):2623-2626
The distribution of ent-2,3-secoaromadendrane-, ent-aromadendrane-, ent-bicyclogermacrane- and ent-maaliane-type sesquiterpenoids in fourteen Plagiochila species is described. These sesquiterpenes are the significant chemosystematic markers of Plagiochila. The intense pungent substance of some Plagiochila species is due to an ent-2,3-secoaromadendrane-type sesquiterpene hemiacetal, plagiochiline A. 相似文献
993.
Yoshinori Asakawa Masao Toyota Masako Kano Tsunematsu Takemoto 《Phytochemistry》1980,19(12):2651-2654
Three new pinguisane-type sesquiterpenes, dehydropinguisanin, dehydropinguisenol and pinguisenal together with the previously known deoxopinguisone, pinguisanin, pinguisanolide and (—)-bicyclogermacrene, have been isolated from the liverwort, Trocholejeunea sandvicensis, and their structures have been established from spectral evidence. 相似文献
994.
Yoshinori Asakawa Masao Toyota Tsunematsu Takemoto Rudiger Mues 《Phytochemistry》1981,20(12):2695-2699
Three liverworts, Trichocolea tomentella, Neotrichocolea bissethii and Trichocoleopsis sacculata belonging to Jungermanniales were chemically investigated. Isoprenyl benzoates are the important chemical markers of Trichocolea tomentella. Neotrichocolea bissethii elaborates sesquiterpenes as the major components. The sacculatane-type diterpenes and pinguisane-type sesquiterpenes are the significant chemosystematic markers of Trichocoleopsis sacculata. These three species are chemically quite different. Trichocoleopsis sacculata is chemically rather close to Porella species. The present chemical results support the recent morphological classification of the above three species proposed by Schuster. Some species of Jungermanniales are chemically identical to those of Metzgeriales and these results also support the phylogenetic classification in which the two orders have been united within the subclass Jungermanniae. 相似文献
995.
Koichi Kato Shuichi Ikeyama Muneo Takaoki Akio Shino Masao Takeuchi Atsushi Kakinuma 《Cell》1981,24(3):885-895
By indirect immunofluorescence microscopy, an antiserum raised in rabbit against serum thymic factor (FTS) was found to decorate the epithelial cells not only in the thymus, but also in the kidney, uterus, urinary bladder, prostatic glands, stomach, ileum, colon, submaxillary glands, trachea, epidermis and epidermal appendages of mouse. The staining ability was completely absorbed with an FTS-binding immunoabsorbent, and affinity-purified anti-FTS IgG showed the same staining patterns as the original antiserum. The staining profiles resembled those described for tissues stained with antiprekeratin and antikeratin antibodies in both distribution in tissue and localization in the epithelial cells. In primary-cultured cells from mouse kidney medullae, the anti-FTS antibodies decorated the cytoplasmic fiber network. The fibers were wavy, bundled together and branched. They were dense in the perinuclear cytoplasm and spread in the cytoplasm toward the cell periphery. This decoration was resistant to colchicine and cytochalasin B, but sensitive to pretreatment with formaldehyde. The organization and shape of the fiber network were similar to those of the networks of intermediate-sized filaments containing cytokeratins, keratins and vimentin. However, the antiserum did not give a precipitin band in immunodiffusion test with prekeratin from bovine muzzle, keratin from human epidermis or 3T3 vimentin. Neither tubulin nor actin formed precipitin bands with the antiserum. These results show that the epithelial cells of various mouse tissues contain FTS or substances close to FTS in chemical structure and suggest that they are associated with the intermediate-sized filaments. 相似文献
996.
Toshihiro Yasuda Daita Nadano Reiko Iida Yukie Tanaka Masao Nakanaga Koichiro Kishi 《Human genetics》1992,89(3):265-269
Summary The objectives of this study were to determine the genetic basis of the electrophoretic differences of human plasma protein C inhibitors (PCI) from 977 individuals. Three discrete antibodies were produced against the PCI purified from human plasma and peptides that corresponded to the N-terminal 15 amino acid residues and the C-terminal 15 residues of human PCI, the chemical structures of which were determined by cDNA sequence analysis. The combined techniques of polyacrylamide gel isoelectric focusing and immunoblotting with these three different antibodies resolved the plasma PCI into several isoprotein bands, with a pH range of 6–7. These PCI isoproteins, however, were not stained by anti-human kallikrein, anti-human protein C or anti-human urokinase antibodies. Therefore, each of the PCI bands, which were detected by immunoblotting with the anti-PCI antibody and the two different anti-peptide antibodies, were derived from free PCI, and not an inactive PCI species. Two common phenotypes, designated PCI 1 and 1–2, were recognized, and family studies showed that they represented homozygosity or heterozygosity for two autosomal codominant alleles, PCI
*1 and PCI
*2. A population study of plasma samples collected from 977 Japanese individuals indicated that the frequencies of the PCI
*1 and PCI
*2 alleles were 0.988 and 0.012, respectively. 相似文献
997.
Masao Nakagaki Ryuzo Takei Eiichi Nagashima Toshinobu Yaginuma 《Development genes and evolution》1991,200(4):223-229
Summary In the silkworm, Bombyx mori, diapause occurs at a specific embryonic stage, i.e. after formation of the germ band with cephalic lobes and telson and sequential mesoderm segmentation. As long as the eggs are incubated at 25° C, cell divisions and morphological development of the embryos cease. To examine changes in percentage of embryonic cells in the G1, S and G2 phases during embryogenesis, nuclear fractions were isolated from embryos, stained with propidium iodide and then subjected to flow cytometric analysis. The percentages of embryonic cells in G1, S and G2 were 10, 35 and 55%, respectively, at the stage of formation of cephalic lobes, whilst 98% of cells were in G2 at diapause stage. After termination of diapause by acclimation at 5° C or by a combination of chilling and HCl, cell division resumed in the embryos. During this period, the cells rapidly entered S phase through G1 from G2, suggesting that their G1 phase was short. In eggs in which diapause was averted by HCl-treatment after incubation at 25° C for 20 h after oviposition, embryonic development proceeded continuously for 9.5 days at 25° C until hatching. Along with this development, the G1 fraction increased to levels of about 90%. These results indicate that embryonic cells are arrested in G2 at diapause and suggest that, concomitant with further embryonic development, cell cycles become slower in proportion to an increasing length of G1. Finally, most of the cells may be arrested in G1, while there is only a small fraction of cells continuously cycling.
Offprint requests to: T. Yaginuma 相似文献
998.
Behavior of Solutions of the Hodgkin-Huxley Equations and its Relation to Properties of Mechanoreceptors 下载免费PDF全文
The membrane current in the Hodgkin-Huxley equations is considered to be a stimulus to the membrane and the responses to the simulus are numerically calculated. Responses of the Hodgkin-Huxley model to an alternating current superimposed upon a constant bias current show qualitative analogy to responses of biological mechanoreceptors. The intensity of the bias current seems to correspond to the degree of adaptation of actual receptors. 相似文献
999.
Immunogens were found associated with particular fractions prepared from spherules ofCoccidioides immitis (Kong, Levine &Smith, 1963) and from yeast cells ofHistoplasma capsulatum (Salvin &Ribi, 1955). However,Blastomyces dermatitidis, another dimorphic systemic fungal pathogen was shown to elicit a minimal immunogenic response in experimental animals (Kong &Levine, 1967). It was therefore deemed pertinent to study factors which might enhance the resistance of mice to infection withB. dermatitidis. 相似文献
1000.
Analysis by ion-exchange chromatography of the enzymes from cultured tobacco cells and root or leaf tissues of the tobacco plant revealed that the cultured cells contain exclusively cationic peroxidases and the leaf tissues mainly anionic and neutral peroxidases. 相似文献