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991.
N. Ben Raïs Aouad I. Ghfir F. Missoum J. Rahali H. Guerrouj R. Ksyar S. Fellah A. Bssis I. Ech-Cherraq 《Médecine Nucléaire》2008,32(11):580-584
Epidemiology of thyroid carcinoma is a complex issue. Data on thyroid carcinoma incidence depend on the efforts undertaken through screening and on the diagnostic methods employed. The objective of this work is to carry out an epidemiologic approach of differentiated thyroid carcinoma (DTC) in our country, with an evaluation of the recent review of literature. This work consists of a retrospective analysis of 3144 cases of differentiated thyroid carcinoma followed in nuclear medicine department of Ibn Sina hospital in Rabat over a period of 20 years. Epidemiology has allowed us to study the influence of gender, age, tumour size, pathological type and prognosis factors in DTC. Epidemiological studies contribute to a better understanding and management of thyroid carcinoma. Further studies are mandatory to determine risk factors and elucidate pathogenetic mechanisms of DT. 相似文献
992.
The viability of Vibrio fluvialis in seawater microcosms, with and without sediment was investigated. The strain survived as culturable bacteria for at least 1 year and the expression of its virulence factors was maintained. In microcosms containing sediment Vibrio fluvialis was more stable. Viable but nonculturable (VBNC) cells of Vibrio fluvialis were able to resuscitate to the culturable state up to 6 years of incubation in marine sediment. These cells recuperate their initial biochemical characteristics after 3 months of incubation in marine broth. Amplified 16S ribosomal DNA (rDNA) restriction analysis (ARDRA) was used to confirm that it is the same strain of Vibrio fluvialis which resists in all microcosms during a long period of time. 相似文献
993.
Roediger B Ng LG Smith AL Fazekas de St Groth B Weninger W 《Histochemistry and cell biology》2008,130(6):1131-1146
Dendritic cells (DCs) within the skin are a heterogeneous population of cells, including Langerhans cells of the epidermis
and at least three subsets of dermal DCs. Collectively, these DCs play important roles in the initiation of adaptive immune
responses following antigen challenge of the skin as well as being mediators of tolerance to self-antigen. A key functional
aspect of cutaneous DCs is their migration both within the skin and into lymphatic vessels, resulting in their emigration
to draining lymph nodes. Here, we discuss our current understanding of the requirements for successful DC migration in and
from the skin, and introduce some of the microscopic techniques developed in our laboratory to facilitate a better understanding
of this process. In particular, we detail our current use of multi-photon excitation (MPE) microscopy of murine skin to dissect
the migratory behavior of DCs in vivo.
B. Roediger and L. G. Ng contributed equally to this work. 相似文献
994.
RNase E is an essential endoribonuclease involved in RNA processing and mRNA degradation. The N-terminal half of the protein encompasses the catalytic domain; the C-terminal half is the scaffold for the assembly of the multienzyme RNA degradosome. Here we identify and characterize 'segment-A', an element in the beginning of the non-catalytic region of RNase E that is required for membrane binding. We demonstrate in vitro that an oligopeptide corresponding to segment-A has the propensity to form an amphipathic alpha-helix and that it avidly binds to protein-free phospholipid vesicles. We demonstrate in vitro and in vivo that disruption of segment-A in full-length RNase E abolishes membrane binding. Taken together, our results show that segment-A is necessary and sufficient for RNase E binding to membranes. Strains in which segment-A has been disrupted grow slowly. Since in vitro experiments show that phospholipid binding does not affect the ribonuclease activity of RNase E, the slow-growth phenotype might arise from a defect involving processes such as accessibility to substrates or interactions with other membrane-bound machinery. This is the first report demonstrating that RNase E is a membrane-binding protein and that its localization to the inner cytoplasmic membrane is important for normal cell growth. 相似文献
995.
Ghada Choho Hikmate Abriouel Nabil Ben Omar Rosario Lucas López Elena Ortega Magdalena Martínez-Cañamero Amin Laglaoui Saïd Barrijal Antonio Gálvez 《World journal of microbiology & biotechnology》2008,24(7):997-1001
A bacteriocin-producing lactic acid bacterium (strain 2.5) isolated from cow’s milk used in cheese production from Northern
Morocco was selected for its strong anti-listerial activity. The producer strain was identified as Enterococcus faecalis by molecular methods. Strain 2.5 carried the genetic determinants for the two-peptide enterococcal bacteriocin enterocin
1071, and the active bacteriocin was purified to homogeneity by reversed-phase chromatography from culture broths of the producer
strain. Strain 2.5 carried two plasmids (of ∼7 and 40 kb). Characterization of strain 2.5 at biosafety level indicated that
this strain is non-haemolytic, and lacks the genetic determinants for most of the virulence factors described in enterococci
(cylB, cylM, gelE, ace and agg) although it carried the genetic determinants cylA, efaAfs as well as determinants for the sex pheromone peptides cpd, cob, and ccf. Strain 2.5 was resistant to tetracycline, rifampicin, and ciprofloxacin, but it was sensitive to penicillin, ampicillin,
vancomycin, and teicoplanin. Results from the present study support the potential role of strain 2.5 as an anti-listerial
agent to be tested in traditional fermented foods. 相似文献
996.
997.
998.
Previously, a 2D gel electrophoresis approach was developed for the Escherichia coli inner membrane, which detects membrane protein complexes that are stable in sodium dodecyl sulfate (SDS) at room temperature, and dissociate under the influence of trifluoroethanol [R. E. Spelbrink et al., J. Biol. Chem. 280 (2005), 28742-8]. Here, the method was applied to the evolutionarily related mitochondrial inner membrane that was isolated from the yeast Saccharomyces cerevisiae. Surprisingly, only very few proteins were found to be dissociated by trifluoroethanol of which Lpd1p, a component of multiple protein complexes localized in the mitochondrial matrix, is the most prominent. Usage of either milder or more stringent conditions did not yield any additional proteins that were released by fluorinated alcohols. This strongly suggests that membrane protein complexes in yeast are less stable in SDS solution than their E. coli counterparts, which might be due to the overall reduced hydrophobicity of mitochondrial transmembrane proteins. 相似文献
999.
I. Toumi M. Gargouri I. Nouairi P. N. Moschou A. Ben Salem-Fnayou A. Mliki M. Zarrouk A. Ghorbel 《Biologia Plantarum》2008,52(1):161-164
To dissect differences in both lipid accumulation and composition and the role of these modifications during drought stress,
four grapevine cultivars exhibiting differential tolerance to drought were subjected to water shortage. Tolerant cultivars,
Kahli Kerkennah and Cardinal, exhibited higher leaf water potential (Ψw), and lower lipid peroxidation compared to the sensitive cultivars Guelb Sardouk and Superior Seedless during stress. Total
lipid amounts increased during stress only in the leaves of the tolerant cultivars. Drought induced increases in the ratios
digalactosyldiacylglycerol/monogalactosyldiacylglycerol and phosphatidylcholine/phoshatidylethanolamine of almost all the
drought stressed cultivars. Moreover, the overall analysis of the composition of fatty acids revealed that a linolenic acid
was prevalent in grapevine and the unsaturation level of lipids increased under water stress in all the cultivars. Specific
adjustments in the lipid composition during stress could compromise stress tolerance. 相似文献