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991.
Jens-Ole Bartz Jochen Blom Hans-Jürgen Busse Jacques B. Mvie Martin Hardt Patrick Schubert Thomas Wilke Alexander Goessmann Gottfried Wilharm Jennifer Bender Peter Kämpfer Stefanie P. Glaeser 《Systematic and applied microbiology》2018,41(2):73-84
Two Gram-stain-negative, facultative anaerobic, motile, rod-shaped strains, S-B4-1UT and JOB-63a, forming small whitish transparent colonies on marine agar, were isolated from a sponge of the genus Haliclona. The strains shared 99.7% 16S rRNA gene sequence identity and a DNA-DNA hybridization value of 100%, but were differentiated by genomic fingerprinting using rep-PCRs. 16S rRNA gene sequence phylogeny placed the strains as a sister branch to the monophyletic genus Endozoicomonas (Oceanospirillales; Gammaproteobacteria) with 92.3–94.3% 16S rRNA gene sequence similarity to Endozoicomonas spp., 91.9 and 92.1% to Candidatus Endonucleobacter bathymodiolin, and 91.9 to 92.1% to the type strains of Kistimonas spp. Core genome based phylogeny of strain S-B4-1UT confirmed the phylogenetic placement. Major fatty acids were summed feature 3 (C16:1 ω7c/C16:1 ω6c) and 8 (C18:1 ω7c/C18:1 ω6c) followed by C10:0 3-OH, C16:0, and C18:0. The G + C content was 50.1–51.4 mol%. The peptidoglycan diamino acid of strain S-B4-1UT was meso-diaminopimelic acid, the predominant polyamine spermidine, the major respiratory quinone ubiquinone Q-9; phosphatidylethanolamine, phosphatidylglycerol and phosphatidylserine were major polar lipids. Based on the clear phylogenetic distinction, the genus Parendozoicomonas gen. nov. is proposed, with Parendozoicomonas haliclonae sp. nov. as type species and strain S-B4-1UT (= CCM 8713T = DSM 103671T = LMG 29769T) as type strain and JOB-63a as a second strain of the species. Based on the 16S rRNA gene sequence phylogeny of the Oceanospirillales within the Gammaproteobacteria, the Endozoicomonaceae fam. nov. is proposed including the genera Endozoicomonas, Parendozoicomonas, and Kistimonas as well as the Candidatus genus Endonucleobacter. 相似文献
992.
The gene encoding endo--1,4-glucanase inBacillus subtilis CK-2 was cloned intoEscherichia coli DH5, and the nucleotide sequence determined. The 1500 bp gene encodes a protein of 499 amino-acid residues with a calculated molecular mass of 55 261, and is equipped with a typicalB. subtilis signal peptide. Nucleotide sequence comparison revealed only 2 basepairs deviation between this gene and the endo--1,4-glucanase gene ofB. subtilis PAP115, and 93% to 95% homology was found between the amino acid sequences of these enzymes and otherB. subtilis endo--1,4-glucanases. Regions of similarity were also observed between the carboxy-terminal part of these enzymes and the part of theB. lautus PL236celA enzyme constituting the cellulose-binding domain. 相似文献
993.
T. A. Schild V. Wagner H. Geldermann 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,89(1):116-120
In order to identify DNA variants within the 5-flanking region of the bovine -casein (Cn)-encoding gene, this area of the gene from 13 cows belonging to seven breeds (Holstein Friesian, Brown Swiss, German Simmental, Jersey, Galloway, Scottish Highland and Ceylon Dwarf Zebu) was analysed. For each individual, about 1 kb of the 5-flanking region including exon I was amplified by polymerase chain reaction (PCR). The biotinylated PCR product was immobilized on magnetic beads followed by direct bidirectional sequencing using an automated DNA sequencer. Fifteen DNA variants were identified, some of which are located within potential regulatory sites and possibly involved in the expression of the -casein encoding gene.Abbreviations
AP2
activator protein 2
-
bp
base pair(s)
-
GRE/RC
glucocorticoid response element/reverse complement
-
HNF3
hepatocyte nuclear factor 3 Cn -casein
-
MGF
mammary gland-specific nuclear factor
-
nt
nucleotid(s), OCT1 octamer-binding site 1
-
PA
polyacrylamide
-
PCR
polymerase chain reaction
-
PMF
pregnancy-specific mammary nuclear factor
-
kb
kilobase(s) or 1000 bp 相似文献
994.
Identification and characterization of gibberellin-insensitive mutants selected from among dwarf mutants of rice 总被引:5,自引:0,他引:5
S. Mitsunaga T. Tashiro J. Yamaguchi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,87(6):705-712
In rice, many dwarf mutants have been isolated and characterized. We have investigated the relationship between dwarfism and the gibberellin (GA)-mediated control of physiological processes. Twenty-three rice cultivars and mutants (9 normal, 3 semi-dwarf, 11 dwarf) were analyzed in terms of two GA-mediated processes, namely, elongation of shoots and production of -amylase activity in the endosperm. As a result, we identified four different groups (groups N, T, D and E). Two-dimensional plotting of the extent of induction of -amylase in the endosperm versus the extent of enhancement of shoot elongation upon treatment with exogenous gibberellic acid (GA3) provided a useful method for the rapid allocation of large numbers of dwarf mutants of rice to the various groups. Members of group N (normal type), which included all normal cultivars and semi-dwarf mutants, showed a slight increase in elongation of shoots and a remarkable increase in production of -amylase with the application of GA3 during germination. All of the dwarf mutants were classified as being members of the other three groups. Members of group T (Tan-ginbozu type), including three dwarf mutants, were highly responsive to exogenous GA3 in terms of elongation of shoots and production of -amylase, with associated lower levels of endogenous GA. In contrast, members of the other three groups, including group N, had normal levels of endogenous GAs. Members of group D (Daikoku type) were only slightly responsive to exogenous GA3, an indication that they are GA-insensitive mutants. Members of group E (Ebisu type) had responses to GA3 similar to those of group N, not only in terms of elongation of shoots but also in terms of -amylase production, an indication that they are dwarf mutants that can be considered as neither GA-deficient nor GA-insensitive mutants. We also examined a GA-insensitive mutant selected from among 19 near-isogenic dwarf lines of Shiokari, and we concluded that the d-1 gene is associated with the phenotype of GA-insensitive dwarf mutants. 相似文献
995.
Hirosato Tanaka Takeshi Watanabe 《Journal of industrial microbiology & biotechnology》1995,14(6):478-483
Summary Lysis of cell walls of various yeast species by -1,3- and -1,6-glucanases ofBacillus circulans WL-12 was investigated. Selective enzymolysis of cell walls ofPyricularia oryzae by single and combined actions of -1,3-, -1,6-glucanases and chitinase was followed. Chemical structure of the cell wall glucan ofP. oryzae was determined by chemical and enzymatic methods. Multiple component nature of glucanases ofB. circulans WL-12, their induction and lytic actions on cell walls of various yeasts were studied. Genes specifying glucanases and chitinases ofB. circulans WL- 12 were cloned inE. coli, and their nucleotide sequences were determined. Fibronectin type III modules were found in the chitinases. Functions of the domains of the deduced structures of the glucanases and the chitinases were studied by various methods including molecular genetic techniques.This paper is dedicated to Professor Herman Jan Phaff in honor of his 50 years of active research which still continues. 相似文献
996.
Immunological detection of tonoplast polypeptides in the plasma membrane of pea cotyledons 总被引:7,自引:0,他引:7
David G. Robinson Hans-Peter Haschke Giselbert Hinz Birgit Hoh Masayoshi Maeshima Francis Marty 《Planta》1996,198(1):95-103
The tonoplast is usually characterized by the presence of two electrogenic proton pumps: a vacuolartype H+-ATPase and a pyrophosphatase, as well as a putative water-channel-forming protein (γ-TIP). Using a post-embedding immunogold labelling technique, we have detected the presence of these transport-protein complexes not only in the tonoplast, but also in the plasma membrane and trans Golgi elements of maturing pea (Pisum sativum L.) cotyledons. These ultrastructural observations are supported by Western blotting with highly purified plasma-membrane fractions. In contrast to the vacuolar-type H+-ATPase, whose activity was not measurable, considerable pyrophosphatase activity was detected in the plasma-membrane fraction. These results are discussed in terms of a possible temporary repository for tonoplast proteins en route to the vacuole. 相似文献
997.
An overview of Acipenseriformes 总被引:14,自引:0,他引:14
Acipenseriformes occupy a special place in the history of ideas concerning fish evolution, but in many respects, phylogenetic studies of the group remain in their infancy. Even such basic questions as the monophyly of Acipenser (the largest genus) are unanswered. We define relationships based on comparative osteology, which allows us to incorporate well-preserved fossils into analyses. Acipenseriformes has existed at least since the Lower Jurassic (approximately 200 MYBP), and all fossil and recent taxa are from the Holarctic. Phylogenetic relationships among Paleozoic and Early Mesozoic actinopterygians are problematic, but most workers agree that Acipenseriformes is monophyletic and derived from some component of paleonisciform fishes. (Paleonisciformes is a grade of primitive non-neopterygian actinopterygians, sensu Gardiner 1993.) Taxa discussed in comparison here are: Cheirolepis, Polypterus, Mimia, Moythomasia, Birgeria, Saurichthys, Lepisosteus and Amia. We review generic diversity within the four nominal families of fossil and recent Acipenseriformes (Chondrosteidae, Peipiaosteidae, Polyodontidae, and Acipenseridae), and provide a cladogram summarizing osteological characters for those four groups. Monophyly of the two extant families is well-supported, but there are no comprehensive studies of all of the known species and specimens of Chondrosteidae and Peipiaosteidae. As a result, sister-group relationships among Chondrosteidae, Peipiaosteidae, and Acipenseroidei (= Polyodontidae + Acipenseridae) are unresolved. We discuss five features fundamental to the biology of acipenseriforms that benefit from the availability of our new phylogenetic hypothesis: (1) specializations of jaws and operculum relevant to jaw protrusion, feeding, and ram ventilation; (2) anadromy or potamodromy and demersal spawning; (3) paedomorphosis and evolution of the group; (4) the bioégeography of Asian and North American polyodontids and scaphirhynchines; and (5) the great abundance of electroreceptive organs in the rostral and opercular regions. Finally, we summarize our nomenclatural recommendations. 相似文献
998.
The impact of elevated atmospheric CO2 on belowground plant growth is poorly understood relative to its effects on aboveground growth. We carried out a study of the seasonal dynamics of gross root production and death to determine how elevated CO2 affected the dynamics of net and gross root production through a full growing season. We quantified gross root production and root loss from sequential, in situ images of fine roots of t Betula papyrifera in ambient (375 ppm.) and elevated (700 ppm) CO2 atmospheres from 2 weeks following germination through leaf senescence. We found that elevated CO2 led to increases in the magnitude of cumulative gross production (P) and cumulative gross loss (L) of roots. However, the effect of elevated CO2 on these processes was seasonally dependent. Elevated CO2 led to greater levels of enhancement in P early in the growing season, prior to maximum standing root length (NP). In contrast, elevated CO2 led to greater levels of enhancement in L in the last half of the growing season, after maximum NP had been reached. This difference in the timing of when elevated CO2 affects P and L led to a transitory, early enhancement in NP. By the end of the growing season, there was no significant effect of elevated CO2 on NP, and P was 87% greater than NP for ambient CO2 and 117% greater in elevated CO2. We conclude that static assessments of belowground productivity may greatly underestimate gross fine root productivity and turnover and this bias can be exaggerated with elevated CO2. 相似文献
999.
Azide-resistant (AzR) mutants of Rhizobium loti strain NZP2037 were isolated. Mutations conferring azide resistance (azi) appeared at a frequency of 0.5 × 10-7. Nine AzR mutants of R. loti were characterised for their symbiotic behaviour with Lotus pedunculatus plants. In comparison to the wild type parent strain, AzR mutants exhibited either similar or higher symbiotic effectiveness. The azi mutations which enhanced nitrogen fixation as well as improving shoot dry weight of the inoculated plants also increased nodulation. Unlike several azi mutations in Escherichia coli, these azi mutations did not alter sensitivity of R. loti to phenethyl alcohol. One of the AzR mutants exhibited higher micro-aerobic, N, N, N, N-tetramethyl-p-phenylenediamine (TMPD) oxidase activity. 相似文献
1000.
Li Cheng Yan Zhao Di Qi Wen Li Daoxin Wang 《Biochemical and biophysical research communications》2018,495(2):1890-1895
T helper cell 17 (Th17), one type of CD4+ T cell, plays an important role in regulating the acute lung injury (ALI) inflammatory response. Recent studies showed that Wnt/β-catenin pathway could modulate the differentiation and the function of CD4+ T cell. However, whether Wnt/β-catenin could regulate the differentiation and function of Th17 in the development and progress of ALI induced by lipopolysaccharide (LPS) is still unknown. To test this, we used dickkopf1 (Dkk-1) to block the Wnt/β-catenin pathway and LiCl to activate the Wnt/β-catenin pathway by instillation to the murine model of ALI. Our results revealed that activation of Wnt/β-catenin pathway significantly aggravated the LPS-induced lung inflammation. Meanwhile, we observed that activation of Wnt/β-catenin pathway promoted Th17 response by analyzing CD4+ T cells and the related cytokines secretions. Enhanced Th17 response was responsible for the further neutrophils infiltration and pro-inflammatory cytokines production. In addition, activation of Wnt/β-catenin pathway resulted in induced expression of retinoic acid related orphan receptor-γt (RORγt) via histone acetyltransferase p300. These data suggested that Wnt/β-catenin pathway might be a potential target to treat the LPS-induced inflammation in ALI. 相似文献