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841.
842.
A simple procedure is described for the assay of phosphorylation using C?erenkov radiation to detect 32P in a liquid scintillation counter. Unreacted 32Pi is first removed from the reaction mixture as the phosphomolybdate complex by butanol/benzene extraction. Addition of ammonium hydroxide to the remaining aqueous fraction avoids color quenching, phase separation, and instability in the counting rate during measurement of 32P. Application of this procedure to several photophosphorylation systems is included. 相似文献
843.
Yamada Yasuyuki; Imaizumi Kazumitsu; Sato Fumihiko; Yasuda Takeshi 《Plant & cell physiology》1981,22(5):917-922
Green tobacco cells were cultured photomixotrophically and photoautotrophicallyin a jar-fermenter (working volume, 5 liters). Optimum aerationand agitation, i.e. the type of impeller (marine), agitationspeed (200 rpm), and aeration rate [1 aeration volume/mediumvolume/min (wm)], and light intensity (8,000 lux) were determinedin order to get high cell growth. Under these conditions, tobaccocells increased about ten fold after 17 days of photomixotrophicculture. In the photoautotrophic culture that had aeration with1% CO2 enriched air, the mass of the tobacco cells did not increasebecause stimulated cell respiration compensated for photosyntheticactivity. A low oxygen supply was essential for photoautotrophicculture in a jar-fermenter. The fresh weight of green tobaccocells increased twice under photoautotrophy, after 17 days ofculture with an agitation of 200 rpm, aeration of 0.8 vvm, withair containing 1% CO2, 14% O2 and 85% N2, and an illuminationof 8,000 lux.
1Present address: Botanical Institute, PL-Women's College, Tondabayashi,Osaka 584, Japan. (Received April 2, 1981; Accepted June 15, 1981) 相似文献
844.
Labeling patterns of light and dark 14CO2-fixation in photoautotrophicallyand photomixotrophically cultured tobacco cells were determined.During short term 14CO2 fixation under light, malate(C3C3carboxylation) was heavily labeled as were phosphoglyceric acidand sugar phosphates(C1C5 carboxylation). Dark fixationcould not account for this high 14CO2 incorporation into theC4 compounds linked to PEPCase. Two carboxylation pathways linkedto the RuBPCase and PEPCase were indicated in 14CO2-fixationin light in photoautotrophically and photomixotrophically culturedcells. (Received October 25, 1979; ) 相似文献
845.
Immunohistochemical localization of lutropin (LH) and follitropin (FSH) in the pituitary gland of the frog Rana japonica was studied by the peroxidase-anti-peroxidase method and the two-face, double-labeling method with different-sized gold particles at the light-and electron-microscopic levels, respectively, using monoclonal antibodies against bullfrog LH and FSH. Light-microscopic immunohistochemistry indicated that approximately 66.0% of all the gonadotrophs in the pituitary contained both LH and FSH, whereas 33.4% of gonadotrophs contained only LH, and 0.6% contained only FSH. The staining intensity of LH and FSH varied from cell to cell. The gonadotrophs were classified into four types (Types I–IV) in terms of their ultrastructural and immunolabeling characteristics. Moreover, several secretory granule types were recognized according to differences in their shape and electron density. In all the cell types, both LH and FSH were often seen in the same secretory granules, but the proportion of granules bearing both hormones ranged from 5.5% in Type I to 32.7% in Type IV. Most secretory granules in Types I and II were immunolabeled with LH alone, whereas a small number of granules were immunolabeled with FSH alone. More immunolabeled FSH granules were present in Types III and IV than in Types I and II. 相似文献
846.
847.
848.
Jun Anzai Fumihiko Takamatsu Kenji Takeuchi Takashi Kohno Kinjiro Morimoto Hideo Goto Nobuyuki Minamoto Akihiko Kawai 《Microbiology and immunology》1997,41(3):229-240
We have investigated a phosphatase-sensitive sequential epitope of the nucleoprotein (N), one of the phosphoproteins of rabies virus, which is recognized by the monoclonal antibody (MAb) #5-2-26. The epitope was shared in common by all of the rabies virus strains we tested, including the HEP, ERA, CVS and Japanese strains (Nishigahara and Komatsukawa). Thin layer chromatography of the acid hydrolyzates of 32P-labeled N protein showed that the protein contained phosphoserine and phospho-threonine at a molar ratio of about 4 to 1, while no phosphotyrosine was detected. Immunoprecipitation studies with several deletion mutants of the N protein showed that the epitope is located in a region spanning from amino acid 344 to 415. If the phosphatase-sensitive epitope is located at or near the phosphoamino acid, the location of the latter could be narrowed further to a region from amino acid 354 to 389 by comparing the amino-acid sequences among the viral strains. To examine this assumption, point mutation was introduced by amino-acid substitution with alanine at either of five potential phosphorylation sites (i.e., positions 354, 375, 377, 386 and 389) in the 354–389 region. Among those, only one substitution, at position 389, greatly affected the antigenicity. Substitution of serine-389 by threonine also reduced the antigenicity. These results strongly suggest that serine-389 is a phosphorylation site and essential for constructing or stabilizing the antigenic structure for MAb 5-2-26. 相似文献
849.
Purification and Characterization of Tobacco Pathogenesis-Related Protein PR-5d, an Antifungal Thaumatin-like Protein 总被引:6,自引:0,他引:6
Koiwa Hisashi; Kato Hiroaki; Nakatsu Toru; Oda Junichi; Yamada Yasuyuki; Sato Fumihiko 《Plant & cell physiology》1997,38(7):783-791
Cultured tobacco cells accumulate several pathogene-sis-relatedproteins. A neutral PR-5 protein, PR-5d, was purified to homogeneityfrom such cells. PR-5d has highly hy-drophobic characteristics,but hydropathy analysis of its primary structure did not showa hydrophobic domain. In a series of bioassays, purified PR-5dshowed inhibitory activity against several phytopathogenic andnon-phytopatho-genic fungi as do other members of the PR-5 proteinfamily. To study the antifungal mechanism based on three dimensionalstructure of PR-5d, purified PR-5d was crystallized. The preliminaryX-ray analysis of the crystal revealed that the crystals belongto space group C2, with cell dimensions a=80.2 Å, b=63.8Å, c=45.7 Å, and ß= 107.2°, and diffractat least 1.8 Å resolution. (Received August 9, 1996; Accepted April 14, 1997) 相似文献
850.
Nobuko Naito Susumu Hyodo Naoto Okumoto Akihisa Urano Yasumitsu Nakai 《Cell and tissue research》1991,266(3):457-467
Summary Biosynthesis of salmon gonadotropins, GTH I and GTH II, during ovarian development, were examined by means of in situ hybridization histochemistry and indirect immunocytochemistry. In rainbow trout pituitary glands, expression of GTH I- and II-subunit genes appeared separately in distinct cells (GTH I- and GTH II-cells), whereas the GTH -subunit gene was expressed in both cell-types. In the GTH I-cells, coordinated increases in GTh, and I messenger ribonucleic acids (mRNAs) occurred coincident with the onset of vitellogenesis, indicating active synthesis of GTH I during vitellogenesis. In contrast, in the GTH II-cells, both GTH -and II-mRNA signals markedly increased from a later stage of vitellogenesis and persisted throughout oocyte maturation and ovulation, supporting the idea that GTH II is actively synthesized as a maturational GTH. GTH -mRNA levels in the GTH I-cells selectively decreased prior to final oocyte maturation, although I-mRNA levels remained elevated, thus suggesting a decline of biosynthesis of GTH I after vitellogenesis. These findings clarify how the synthesis of GTH I and GTH II are coordinated in the piscine pituitary, and indicate that the expression of GTH subunit genes during gametogenesis is regulated differentially in a cell-specific manner, both temporally and spatially. 相似文献