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1.
Yusuke Nakamura Michio Ogawa Takahiro Nishide Mitsuru Emi Goro Kosaki Seiichi Himeno Kenichi Matsubara 《Gene》1984,28(2):263-270
The nucleotide sequences of the cloned human salivary and pancreatic α-amylase cDNAs correspond to the continuous mRNA sequences of 1768 and 1566 nucleotides, respectively. These include all of the amino acid coding regions. Salivary cDNA contains 200 bp in the 5′-noncoding region and 32 in the 3′-noncoding region. Pancreatic cDNA contains 3 and 27 bp of 5′- and 3′-noncoding regions, respectively. The nucleotide sequence humology of the two cDNAs is 96% in the coding region, and the predicted amino acid sequences are 94% homologous.Comparison of the sequences of human α-amylase cDNAs with those previously obtained for mouse α-amylase genes (Hagenbuchle et al., 1980; Schibler et al., 1982) showed the possibility of gene conversion between the two genes of human α-amylase. 相似文献
2.
Kimitaka Yakura Atsushi Kato Shigeyuki Tanifuji 《Molecular & general genetics : MGG》1984,193(3):400-405
Summary The DNA fragments including the whole large spacer region of Vicia faba rDNA were cloned in plasmid pBR325. Sixteen clones were classed into five groups which differed from each other in the lengths of the rDNA inserts. Physical maps of these length variants cloned were constructed using EcoRI, SalI, HpaI, MluI and AccI and evidence was obtained that the length heterogeneity was due mainly to the differing number of 325 base pairs (bp) subrepeating elements in the large spacer. Sequence analysis of this subrepeating element revealed that it consisted of a duplet of an approximately 155 bp sequence and a 14 bp unrelated sequence. This structure of the repetitive element is novel. 相似文献
3.
EcoRI-fragments of Vicia faba rDNA were cloned in plasmid pBR325.Southern blot hybridization of BamHI-digests of these clonedplasmids and Vicia genomic DNA led to the determination of relativepositions of BamHl sites in the rDNA and the physical map thathad been tentatively made is corrected. (Received May 20, 1982; Accepted July 13, 1983) 相似文献
4.
Ferredoxin-sulfite reductases (Fd-SiRs) [hydrogen-sulfide: ferredoxin oxidoreductase, EC 1.8.7.1] from leek leaves have been
purified to homogeneity. The enzymes (SiR 1, SiR 2 and SiR 3) were separated by Mono Q chromatography. The collective molecular
mass of the enzymes was estimated to be 65 kDa by gel filtration. In all three cases, subunit analysis by SDS-PAGE yielded
a single protein band corresponding to a molecular mass of 64 kDa, indicating that the enzymes each exist as a monomer. In
the oxidized forms, SiR 1, SiR 2 and SiR 3 all exhibited nearly identical absorption maxima at 279∼280, 389∼390, 588 and 714
nm, indicating that siroheme is involved in the catalysis of sulfite reduction. On enzymatic properties, SiR 1, SiR 2 and
SiR 3 could only react with the physiological electron donor, feriedoxin. The enzymes exhibited different heat stabilities.
The pH active curve obtained from SiR 2 was different from the others. Moreover, SiR 1 exhibited a lower Km value for ferredoxin
than SiR 2. Although the N-terminal sequence was the same, the results of some enzymatic properties, amino acid analysis,
and peptide mapping suggested the presence of the Fd-SiR isozymes in leek leaves. 相似文献
5.
Petunia guarapuavensis (Solanaceae): A new species from planalto of Paraná and Santa Catarina,Brazil
Petunia guarapuavensis, a new species fromplanalto (high plateau) of Paraná and Santa Catarina in Brazil, is described, and its morphological distinction from related species, features of the habitats, and geographical distribution are discussed. 相似文献
6.
When carrot explants were cultured with phytohormones, DNA synthesistook place synchronously in the explants and a satellite DNAwith a heavier density in CsCl than the bulk DNA replicatedin the earliest phase of the first replication period. The earlyreplicating carrot satellite consisted of a component havingan identical density to carrot rDNA and another component havinga density between the p-value of carrot rDNA and that of thebulk DNA. DNA-rRNA hybridization was used to explore the possibilitythat this early replication of the satellites leads to amplificationof rDNA in the explant cells, in which massive ribosome synthesisis known to occur. The results showed that there was neitheramplification nor underreplication of rRNA genes during callusformation and its growth. Experiments with explants of Jerusalem artichoke tuber, whichare well known as a synchronous replication system, showed thata component slightly heavier than the bulk DNA was synthesizedat the early phases of the first replication period. However,the density of this early replicating satellite differed fromthat of artichoke rDNA. DNA-rRNA hybridization experiments againshowed no gross changes of rDNA content during dedifferentiationof this plant system. (Received September 30, 1981; Accepted January 5, 1982) 相似文献
7.
8.
The effect of 6059-S, a novel 1-oxacephem, on peptidoglycan synthesis was investigated using ether-treated cells of Escherichia coli K 12, Pseudomonas aeruginosa KM 338 and Serratia marcescens IFO 12648. The cross-linking reaction of peptidoglycan synthesis in these organisms was inhibited by markedly low concentration of 6059-S.Non-standard abbreviations PBP
penicillin binding protein
- MIC
minimum inhibitory concentration
- ETB
ether treated bacterial cells
- SDS
sodium dodecylsulfate 相似文献
9.
The basic chromatin structure of higher plants (Vicia faba andTrillium kamtschaticum) was examined biochemically. After digestionwith micrococcal nuclease, the chromatins of these species yieldedDNA-protein components which sedimented as discrete peaks at11S, 15S, 19S, and so on in a sucrose gradient. The buoyantdensity of Vicia chromatin subunits was about 1.44 g?cm3in CsCl. Polyacrylamide gel electrophoresis of histone fromthese subunits of Vicia and Trillium chromatins indicated thatthe 11S monomer contained very little histone H1 but a fullcomplement of all other histones, whereas the oligomers containedH1 as in the case of undigested chromatin. Therefore, the modeof organization of basic chromatin structure in higher plantsis identical with that reported with various other eukasyotes,although two plant histone components are different from thecorresponding mammalian histones, H2A and H2B, in molecularweight and amino acid composition. The results indicated alsothat chromosomes prepared from Trillium meiotic cells do notdiffer from chromatins of Trillium or Vicia somatic cells inthe sensitivity to nuclease digestion or in the size of theirsubunits. (Received May 19, 1978; ) 相似文献
10.
δ-Aminolevulinic acid (ALA) synthase was partially purified from liver cytosol fraction of rats treated with allylisopropylacetamide (AIA). The cytosol ALA synthase showed an apparent molecular weight of 320,000. The cytosol ALA synthase of this size dissociates into at least three protein components when subjected to sucrose density gradient centrifugation in the presence of 0.25 m NaCl: one is the catalytically active protein with an s value of about 6.4 or a molecular weight of 110,000, and the other two are catalytically inactive binding proteins showing s values of about 4 and 8, respectively. Recombination of the 6.4 S protein and the 4 S protein yielded a protein complex with an apparent molecular weight of 170,000 and recombination of all three protein components resulted in formation of the original cytosol ALA synthase. The cytosol ALA synthase also loses its binding proteins when treated with various proteases; thus, the enzyme-active protein obtained after papain digestion was very similar, if not identical, to mitochondrial ALA synthase. When treated with trypsin, however, the cytosol ALA synthase was converted to an enzyme showing an apparent molecular weight of 170,000, which probably represents the complex of the mitochondria-type enzyme and the 4 S binding protein. The cytosol ALA synthase tends to aggregate to form a dimer with an apparent molecular weight of 650,000–700,000. The aggregated form of the cytosol ALA synthase was less susceptible to trypsin digestion. Hemin strongly stimulated dimer formation of the cytosol ALA synthase and the aggregate produced by contact with hemin was very tight and did not easily dissociate into its respective protein components by sucrose gradient centrifugation or even after treatment with trypsin. The possible mechanisms of the conversion of cytosol ALA synthase to the mitochondrial enzyme and also of the inhibition by hemin of the intracellular translocation of ALA synthase are discussed. 相似文献