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981.
982.
S-formylglutathione hydrolase of Paracoccus denitrificans is homologous to human esterase D: a universal pathway for formaldehyde detoxification? 下载免费PDF全文
N Harms J Ras W N Reijnders R J van Spanning A H Stouthamer 《Journal of bacteriology》1996,178(21):6296-6299
Downstream of flhA, the Paracoccus denitrificans gene encoding glutathione-dependent formaldehyde dehydrogenase, an open reading frame was identified and called fghA. The gene product of fghA showed appreciable similarity with human esterase D and with the deduced amino acid sequences of open reading frames found in Escherichia coli, Haemophilus influenzae, and Saccharomyces cerevisiae. Mutating fghA strongly reduced S-formylglutathione hydrolase activity. The mutant was unable to grow on methanol and methylamine, indicating that the enzyme is essential for methylotrophic growth. S-Formylglutathione hydrolase appears to be part of a formaldehyde detoxification pathway that is universal in nature. 相似文献
983.
Genes associated with meningococcal capsule complex are also found in Neisseria gonorrhoeae. 总被引:1,自引:0,他引:1 下载免费PDF全文
H Petering S Hammerschmidt M Frosch J P van Putten C A Ison B D Robertson 《Journal of bacteriology》1996,178(11):3342-3345
A homolog of the meningococcal cps locus region E has been identified in Neisseria gonorrhoeae immediately upstream of the gonococcal region D locus. Region E has no detectable function in capsule biosynthesis in Neisseria meningitidis or in lipopolysaccharide biosynthesis in either organism. The open reading frame is homologous to proteins of unknown function in Escherichia coli and Haemophilus influenzae. Further analysis of the N. meningitidis cps cluster has identified a second copy of region D encoding three additional open reading frames, including homologs of DNA methyltransferases. The organization of the region D and E genes in N. gonorrhoeae and N. meningitidis in relation to the cps genes provides some insight into the evolutionary origin of encapsulation in N. meningitidis. 相似文献
984.
Identification of the mpl gene encoding UDP-N-acetylmuramate: L-alanyl-gamma-D-glutamyl-meso-diaminopimelate ligase in Escherichia coli and its role in recycling of cell wall peptidoglycan. 下载免费PDF全文
A gene, mpl, encoding UDP-N-acetylmuramate:L-alanyl-gamma-D-glutamyl-meso-diaminopimelat e ligase was recognized by its amino acid sequence homology with murC as the open reading frame yjfG present at 96 min on the Escherichia coli map. The existence of such an enzymatic activity was predicted from studies indicating that reutilization of the intact tripeptide L-alanyl-gamma-D-glutamyl-meso-diaminopimelate occurred and accounted for well over 30% of new cell wall synthesis. Murein tripeptide ligase activity could be demonstrated in crude extracts, and greatly increased activity was produced when the gene was cloned and expressed under control of the trc promoter. A null mutant totally lacked activity but was viable, showing that the enzyme is not essential for growth. 相似文献
985.
J. G. M. van Nistelrooy J. M. van den Brink J. A. L. van Kan R. F. M. van Gorcom M. A. de Waard 《Molecular & general genetics : MGG》1996,250(6):725-733
TheCYP51 gene encoding eburicol 14-demethylase (P45014DM) was cloned from a genomic library of the filamentous fungal plant pathogenPenicillium italicum, by heterologous hybridisation with the corresponding gene encoding lanosterol 14-demethylase from the yeastCandida tropicalis. The nucleotide sequence of a 1739-bp genomic fragment and the corresponding cDNA clone comprises an open reading frame (ORF) of 1545 bp, encoding a protein of 515 amino acids with a predicted molecular mass of 57.3 kDa. The ORF is interrupted by three introns of 60, 72 and 62 bp. The C-terminal part of the protein includes a characteristic haem-binding domain, HR2, common to all P450 genes. The deducedP. italicum P45014DM protein and the P45014DM proteins fromCandida albicans, C. tropicalis andSaccharomyces cerevisiae share 47.2, 47.0 and 45.8% amino acid sequence identity. Therefore, the cloned gene is classified as a member of theCYP51 family. Multiple copies of a genomic DNA fragment ofP. italicum containing the cloned P450 gene were introduced intoAspergillus niger by transformation. Transformants were significantly less sensitive to fungicides which inhibit P45014DM activity, indicating that the cloned gene encodes a functional eburicol 14-demethylase. 相似文献
986.
Mark A. Pook Rekhaben Thakrar Bruce Pottinger Brian Harding David Porteous Veronica van Heningen John Cowell Carol Jones Sue Povey Kay E. Davies Rajesh V. Thakker 《Human genetics》1996,97(6):742-749
EagI and NotI linking libraries were prepared in the lambda vector, EMBL5, from the mouse-human somatic cell hybrid 1W1LA4.9, which contains
human chromosomes 11 and Xp as the only human component. Individual clones containing human DNA were isolated by their ability
to hybridise with total human DNA and digested with SalI and EcoRI to identify the human insert size and single-copy fragments. The mean (± SD) insert sizes of the EagI and NotI clones were 18.3 ± 3.2 kb and 16.6 ± 3.6 kb, respectively. Regional localisation of 66 clones (52 EagI, 14 NotI) was achieved using a panel of 20 somatic cell hybrids that contained different overlapping deletions of chromosomes 11
or Xp. Thirty-nine clones (36 EagI, 3 NotI) were localised to chromosome 11; 17 of these were clustered in 11q13 and another nine were clustered in 11q14–q23.1. Twenty-seven
clones (16 EagI, 11 NotI) were localised to Xp and 10 of these were clustered in Xp11. The 66 clones were assessed for seven different microsatellite
repetitive sequences; restriction fragment length polymorphisms for five clones from 11q13 were also identified. These EagI and NotI clones, which supplement those previously mapped to chromosome 11 and Xp, should facilitate the generation of more detailed
maps and the identification of genes that are associated with CpG-rich islands.
Received: 27 December 1995 / Revised: 30 January 1996 相似文献
987.
Louise Warnich Peter N. Meissner Richard J. Hift Jan H. Louw Carel J. van Heerden Andries E. Retief 《Human genetics》1996,97(5):690-692
The gene for variegate porphyria (VP), an autosomal dominant disease with a high prevalence in South Africa, evidently due
to a founder effect, was previously mapped to chromosome 14q32. In the current study this localization was evaluated by linkage
and haplotype analyses using microsatellite markers spanning a region of more than 20 cM on chromosome 14q32. In many recent
studies linkage disequilibrium between disease and marker loci has been utilized to map genes in founder populations, but
we could not find any association between VP and the markers used in this study. Our data suggest that the allocation of VP
to chromosome 14q32 may be incorrect.
Received: 1 September 1995 / Revised: 1 November 1995 相似文献
988.
Fiber-specific regulation of Ca(2+)-ATPase isoform expression by thyroid hormone in rat skeletal muscle 总被引:1,自引:0,他引:1
989.
Sheila H. Luijten J. Gerard B. Oostermeijer Nico C. van Leeuwen Hans C. M. den Nijs 《Plant Systematics and Evolution》1996,201(1-4):15-30
In a medium-sized population ofArnica montana, a threatened species in The Netherlands, the breeding system, reproductive success and genetic clonal structure were studied. Pollination experiments suggested thatA. montana is largely self-incompatible. Inbreeding depression was observed for seedling weight but not for fruit weight and germination rate. Although genetic variation is rather low in this population, the data suggest an outcrossing mating system. Analysis of the genotype of all mapped rosettes in a plot of 100 m2 indicated that dense clusters often consist of identical genotypes, suggesting a clonal structure. Open clusters frequently contained several different genotypes. This may be caused by limited fruit dispersal, since seedlings were found mainly within or in the near surroundings of the clusters. 相似文献
990.
Summary We report here an efficient Arabidopsis leafdisc transformation protocol yielding an average transformation frequency of 1.6 transgenic shoots per leaf explant 4 weeks after the bacterial infection period. Subsequent cultivation in vitro is such that a high percentage (85–90%) of the primary transformants produces seeds with an average seed yield of 100–300 seeds per plant. This improved transformation protocol yields mainly (70%) transformants segregating for a single T-DNA locus of which 68% actually contain one T-DNA insert. The objective is to generate a pool of independent transformants harboring an activator T-DNA construct in a gene tagging approach to isolate genes involved in morphogenesis and auxin signal transduction.Abbreviations
2,4-D
2,4-dichlorophenoxyacetic acid
-
AGM
Arabidopsis growth medium
-
BAP
benzylaminopurine
-
CaMV
Cauliflower Mosaic Virus
-
CTAB
Hexadecyltrimethylammoniumbromide
-
DIG
digoxigenin
-
FeNaEDTA
Iron-sodium-ethylenedinitrilo tetraacetic acid complex
-
GUS
ß-Glucuronidase
-
IBA
indole-3-butyric acid
-
LB
left T-DNA border
-
MES
2-(N-morpholino) ethane sulfonic acid
-
MS
Murashige and Skoog medium
-
NAA
-naphthaleneacetic acid
-
RB
right T-DNA border 相似文献