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991.
Somatic hybrids obtained by fusion betweenPoncirus trifoliata (2x) andFortunella hindsii (4x) protoplasts 总被引:5,自引:0,他引:5
M. Miranda T. Motomura F. Ikeda T. Ohgawara W. Saito T. Endo M. Omura T. Moriguchi 《Plant cell reports》1997,16(6):401-405
Somatic hybrids were obtained by the symmetric fusion of embryogenic callus cells from tetraploid Mame kumquat [Fortunella hindsii (Champ.) Swing.] and mesophyll cells from diploid trifoliate orange [Poncirus trifoliata (L.) Raf.]. Southern blot analysis of three regenerants revealed that they carried specific rDNA fragments from both fusion partners, thereby confirming their hybridity. In contrast, mitochondrial DNA (mtDNA) and chloroblast DNA (cpDNA) were unidirectionally transmitted from the callus parent without any evidence of recombination. No differences in the restriction fragment patterns of rDNA, mtDNA or cpDNA could be detected among the regenerants. Flow cytometry showed that two regenerants were hexaploids, as expected, but that one was pentaploid, probably due to elimination of chromosomes prior to the regeneration of this plant.Abbreviations
MS
Murashige and Skoog (1962)
-
DIG
digoxigenin
-
AMPPD
3-(2-spiroadamantane)-4-methoxy-4-(3-phosphoryloxy)-phenyl-1,2-dioxetane
-
FACS
fluorescence-activated cell sorter 相似文献
992.
Germplasm conservation of the tropical forest trees,Cedrela odorata L.,Guazuma crinita Mart., andJacaranda mimosaefolia D. Don., at above-freezing temperatures following alginate-bead encapsulation was attempted. Shoot tips excised from in vitro plantlets were encapsulated in calcium-alginate beads and stored on different substrates at 12, 20, and 25 °C. Percent viability when encapsulated shoot tips were stored on substrate containing only water solidified with 1% (wt/vol) agar was 80% after 12 months at 12°C forC. odorata, 90% after 12 months at 25°C forG. crinita, and 70% after 6 months at 20°C forJ. mimosaefolia.Abbreviations
BAP
6-Benzylaminopurine
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KIN
6-Furfurylaminopurine 相似文献
993.
Moriguchi Toru Matsuura Hiromichi Kodera Yukihiro Itakura Yoichi Katsuki Hiroshi Saito Hiroshi Nishiyama Nobuyoshi 《Neurochemical research》1997,22(12):1449-1452
Several organosulfur compounds found in garlic extract promoted the survival of rat hippocampal neurons in vitro. From the analysis of structure-activity relationship, thioallyl group in these compounds is essential for the manifestation of neurotrophic activity. S-Allyl-L-cysteine (SAC), one of the organosulfur compounds having thioallyl group in garlic extract, also promoted the axonal branching of cultured neurons. These results suggest that thioallyl compounds make a unique group of neurotrophic factors. 相似文献
994.
Concentration and Membrane Fluidity Dependence of Odor Discrimination in the Turtle Olfactory System 总被引:1,自引:0,他引:1
Kashiwayanagi Makoto; Sasaki Kazuyo; lida Akio; Saito Hanako; Kurihara Kenzo 《Chemical senses》1997,22(5):553-563
In the present study, we examined the concentration dependenceof odor discrimination in turtle olfactory bulbar responsesusing the cross-adaptation technique. In the odorant pairs withdiverse molecular structures, the degree of discrimination wasunchanged or only slightly decreased with an increase in odorantconcentrations, suggesting that odorants are well discriminatedeven at high concentrations. In the odorant pairs with closelyrelated molecular structures, the degree of discrimination wasdecreased with an increase in odorant concentrations. An increasein the temperature of turtle olfactory epithelium also decreasedthe ability to discriminate these odorants. There was a goodcorrelation between changes in the odor discriminating abilityinduced by an increase in odor concentrations and those inducedby a temperature increase. The liposomes were made of lipidsextracted from the turtle olfactory epithelia and changes oftheir membrane fluidity induced by adsorption of odorants weremonitored with DPH. There was a good correlation between a decreasein odor discriminating ability and the membrane fluidity changesinduced by odorants. We suggest that decreases in odor discriminatingability induced either by an increase in odor concentrationor by a temperature increase are ultimately caused by changesin the membrane fluidity. Chem. Senses 22: 553563, 1997. 相似文献
995.
996.
Izumi Saito 《Mycoscience》1997,38(2):227-236
A newSclerotinia, previously reported asS. intermedia from Japan, is described asSclerotinia nivalis on the morphological basis of the sclerotial anamorph and teleomorph produced in culture. The characters assigning this species
to the genusSclerotinia are the tuberoid sclerotia superficially produced on suscepts, the small sclerotia produced on aerial mycelium in culture,
the interhyphal spaces in medullary tissue of sclerotia, and the globose cells constructing the ectal excipulum of apothecia.
It is distinguishable fromS. sclerotiorum, S. minor, andS. trifoliorum by the intermediate sized sclerotia in culture, binucleate ascospores, the molecular mass of major proteins of sclerotia,
and the patterns of esterase isozymes in sclerotial extracts. AlthoughS. nivalis causes snow mold of various dicots, it is a mesophile having an optimum temperature for mycelial growth of around 20°C. It
attacks edible burdock(Arctium lappa), Chryhsanthemum morifolium, Ambrosia elatior, carrot(Daucus carota), Angelica acutiloba, Ajuga reptans, andPlantago lanceolata. 相似文献
997.
A new member of the sulphate transporter gene in
Arabidopsis encoding a chloroplast-localizing isoform,
AST82 (accession no. AB008782) has been identified.
AST82 had a sequence similarity with a cyanobacterial
genome sequence, slr1776, which encodes a putative
eukaryotic proton/sulphate co-transporter. Fusion proteins of
AST82 and green fluorescent protein (GFP) transiently
expressed in Arabidopsis leaves localized in
chloroplasts, indicating that AST82 encodes a
chloroplastic isoform. 相似文献
998.
999.
1000.