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991.
992.
993.
M. Sibi M. Biglary Y. Demarly 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1984,68(4):317-321
Summary Modification to the cross-over (C. O.) rate of tomato (Lycopersicon esculentum) was attempted by using in vitro plant regeneration. F1 hybrids with the same genetical homozygous background were compared at two loci: bs-ms32 on chromosome I, and aa-d on chromosome II. For each, the genetic distance separating the two markers was about 20 to 30 map units. One cotyledon of each F2 hybrid seedling was used as in vitro tissue culture material, while the rest of the plantlet was grown as a control. Recombination rates of the selfed progenies from each regenerated and matched control couple were compared. For the first set of markers 59,000 seeds were analysed (5 controls' and 7 regenerated progenies), and for the second, 11,000 (5 controls' and 8 regenerated progenies). There were significant increases in the genetic distance between markers in about half the regenerated individuals. For the first set the increases ranged from 6.07 to 6.91 units out of a control distance of the 19.84 to 25.65, corresponding to lengthenings of 30.59 to 35.29%. For the second set they ranged from 4.92 to 6.04 out of a control distance of 25.05 to 26.57, representing increases of 19.64 to 22.75%. Such a phenomenon can be important either from a fundamental or practical viewpoint, regarding selection efficiency in plants, and potential for gene reassortment.The experiment reported in this paper has been submitted by M. Biglary in partial fulfillment of the requirements for Docteur-Ingénieur degree. (Nov. 1982, Laboratoire d'Amélioration des Plantes, Université Paris-Sud, F-91405 Orsay) 相似文献
994.
Alexander Tschopp Augusto Cogoli Marian L. Lewis Dennis R. Morrison 《Journal of biotechnology》1984,1(5-6)
Attachment to a substrate and survival of human embryonic kidney (HEK) cells have been tested in an incubator installed in the flight-deck of the Space Shuttle ‘Challenger’ during its eighth mission.HEK cells are producing the enzyme urokinase and are presently investigated as candidates for electrophoretic separation in an apparatus developed and manufactured by McDonnell Douglas.Attachment of HEK cells to a substrate is mandatory for survival and production of urokinase after electrophoretic separation.Analysis of the samples shows that cells adhere, spread and survive in microgravity (< 10−3 ×g) conditions as well as the ground controls at 1 × g. This result represents an important step towards further bioprocessing in space. 相似文献
995.
Jacqueline Besson Monique Dussaillant Jean-Claude Marie William Rostene Gabriel Rosselin 《Peptides》1984,5(2):339-340
This paper describes the autoradiographic distribution of VIP binding sites in the rat central nervous system using monoiodinated 123I-labeled VIP. High densities of VIP binding sites are observed in the granular layer of the dorsal dentate gyrus of the hippocampus, the basolateral amygdaloid nucleus, the dorsolateral and median geniculate nuclei of the thalamus as well as in the ventral part of the hypothalamic dorsomedial nucleus. 相似文献
996.
In vitro autoradiographic localization of [I]-angiotensin II binding sites in the rat and dog kidney
Light microscopic autoradiographic techniques have been utilized to demonstrate specific regions of the rat and dog kidney where angiotensin II receptors exist. Slide mounted tissue sections were labeled with [125I]-angiotensin II using conditions which provided for highly specific binding. These angiotensin II binding sites were localized to several distinct renal structures. In the renal cortex, angiotensin II binding sites were found concentrated in all parts of the glomeruli including the vascular components, the macula densa and the juxtaglomerular apparatus. Angiotensin II binding in the medulla was more diffusely associated with the vasa recta, and to a lesser extent, the thick ascending segment of the loop of Henle. Binding sites specific for angiotensin II were also found in the smooth muscle laminae of the ureter. Scatchard analysis of the binding kinetics allowed the demonstration of two subpopulations of binding sites which differ slightly in their affinities for [125I]-angiotensin II. These subpopulations appear to be associated with distinct components of the renal structure. 相似文献
997.
Kathleen Dobrosielski-Vergona 《In vitro cellular & developmental biology. Plant》1984,20(11):889-892
Summary Glucose-6-phosphatase activity decreases whereas gamma glutamyltranspeptidase activity increases during hepatocarcinogenesis
and the maintenance of hepatocytes in primary culture. This report describes the effect of culture conditions that are known
to preserve hepatic glucose-6-phosphatase activity on gamma glutamyltranspeptidase activity. The results indicate that the
regulation of glucose-6-phosphatase and gamma glutamyltranspeptidase activities is not coordinated in primary cultures of
hepatocytes.
This work was supported by a grant from the USPHS, NIH grant AG00439 awarded to Dr. Christopher C. Widnell and a Category
I Research Development Award from the University of Pittsburgh to Dr. Kathleen Dobrosielski-Vergona.
Editor's Statement Information communicated in this article contributes to a greater understanding of the mechanisms regulating
liver cell metabolism and provides some further insight concerning the complexity of the controls involved in vitro, and presumably
in vivo. David W. Barnes 相似文献
998.
Paul S. Moss Dennis H. Spector Charles A. Glass Richard C. Strohman 《In vitro cellular & developmental biology. Plant》1984,20(6):473-478
Summary As part of an effort to optimize conditions required for the complete maturation of muscle cells in vitro, we have investigated
the effects of the antibiotics penicillin, streptomycin, and Fungizone (amphotericin B) on the development of cultured chick
embryo skeletal muscle. It is shown that even low dosages of streptomycin, but not penicillin or Fungizone, retard protein
synthesis and accumulation in these cultures. Myosin accumulation was also reduced and the appearance of striations in fused
cells was delayed in myotubes formed in medium containing streptomycin. Additional data suggest that this overall retardation
of myogenesis is due to the influence of streptomycin on maturing myotubes rather than early proliferation and cell fusion.
These results are discussed with regard to recent efforts to promote the full maturation of muscle cells grown in culture.
This research was supported by National Institutes of Health Grant NS 155882 and a Task Force on Drug Development Research
Contract from The Muscular Dystrophy Association. 相似文献
999.
Michael Ma Shuenn-Jue Wu Maureen Howard Alexej B. Borkovec 《In vitro cellular & developmental biology. Plant》1984,20(9):739-742
Summary We report here that the use of murine thymoma cell EL-4 conditioned medium enhances hybridoma yield in a low-antigen dose
in vitro immunization protocol. This improved protocol allowed the production of a panel of monoclonal antibodies toDrosophila yolk proteins using less than 1 nanomole of antigen. We believe this refinement will be valuable for the application of hybridoma
technology to biologically active materials that are hard to isolate and purify due to their low concentration in the biological
fluids.
This research was supported by the College of Agriculture and Life Sciences, University of Maryland, USDA-University of Maryland
Cooperative
Editor's Statement This observation should simplify in vitro immunization approaches and shed new light on the factors required
for the in vitro immune response. Wallace L. McKeehan 相似文献
1000.
Summary Growth characteristics of human esophageal epithelial cells have been determined in primary explant and serial culture. Normal
human esophagus was obtained from donor patients in a heart/lung transplantation program; tissue obtained at autopsy (6 to
22 h after death) was not viable. When mucosal specimens (1.5 mm2) were explanted on a plastic surface and attached with a plasma clot, 35% of explants detached from the surface within 48
h. The addition of epsilon amino caproic acid (EACA) to the culture medium increased explant attachment of 93% (P<0.001). Outgrowth kinetics were similar in both the presence and absence of EACA. No advantage of human serum over nonhuman
sera was observed in primary culture. Esophageal epithelium could be frozen in 10% dimethyl sulfoxide without affecting growth
kinetics. Addition of dexamethasone (DEX) significantly altered esophageal cell morphology in primary culture and increased
viability on serial culture. Studies of pH revealed an optimum at pH 7.4 with significantly decreased growth occuring at 6.8
and no growth at 6.2.
Esophageal cells in primary explant cultures could be released by trypsin and passaged two additional times with an eightfould
increase in total number. An increased rate of attachment and multiplication was observed for cells plated on a collagen substrate
compared to platic.
The addition of EACA and DEX to the culture media and the subculture on a collagen substrate provide a method for the isolation
and serial cultivation of human esophageal cells from biopsy-sized specimens of normal esophageal epithelium.
Supported in part by Grant AM—14121 of the United States Public Health Service. A preliminary report of this work appeared
in Clin. Res. 30: 93A; 1982. 相似文献