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911.
912.
Duong Thi Huong Giang Edilbert Van Driessche Isabel Vandenberghe Bart Devreese Sonia Beeckmans 《Fish & shellfish immunology》2010,28(5-6):743-753
From the serum of Pangasianodon hypophthalmus, two proteins were isolated by affinity chromatography on Sepharose and phosphorylcholine–Sepharose. Their binding on the affinity matrices critically depends on the presence of Ca2+ ions. N-terminal sequencing and sequencing of internal tryptic peptides identified the proteins as pentraxins and from their binding properties they are identified as SAP (serum amyloid P component) and CRP (C-reactive protein). Per ml serum, 36 μg SAP and 56 μg CRP was purified. Upon gel filtration, both the SAP and CRP elute as trimers of respectively 24 kDa and 28 kDa subunits. Both proteins are devoid of inter-chain disulfide bonds. Both SAP and CRP are glycosylated and agglutinate rabbit erythrocytes and pathogenic bacteria Edwardsiella ictaluri and Aeromonas hydrophila, but not Micrococcus lysodeikticus or Escherichia coli. Haemagglutination of SAP and CRP is inhibited by galactose (MIC = 1 mM) and by phosphorylcholine (MIC = 1–2 mM), respectively. Circular dichroism studies revealed that antiparallel β-pleated sheets are dominating the secondary structure. Upon removing the Ca2+ ions by EDTA, slight structural changes are observed by CD spectroscopy in the near-UV region. Immunodiffusion shows that P. hypophthalmus SAP and CRP do not cross-react. 相似文献
913.
Arianna Tavanti Lambert AM Hensgens Selene Mogavero László Majoros Sonia Senesi Mario Campa 《BMC microbiology》2010,10(1):203
Background
Candida parapsilosis is known to show limited genetic variability, despite different karyotypes and phenotypes have been described. To further investigate this aspect, a collection of 62 sensu strictu C. parapsilosis independent isolates from 4 geographic regions (Italy, n = 19; New Zealand, n = 15; Argentina, n = 14; and Hungary, n = 14) and different body sites (superficial and deep seated) were analysed for their genetic and phenotypic traits. Amplification fragment length polymorphism (AFLP) analysis was used to confirm species identification and to evaluate intraspecific genetic variability. Phenotypic characterisation included clinically relevant traits, such as drug susceptibility, in vitro biofilm formation and aspartyl protease secretion. 相似文献914.
Natacha Olieric Melanie Kuchen Sandro Wagen Marion Sauter Stephanie Crone Sonia Edmondson Daniel Frey Christian Ostermeier Michel O Steinmetz Rolf Jaussi 《BMC biotechnology》2010,10(1):56
Background
Molecular DNA cloning is crucial to many experiments and with the trend to higher throughput of modern approaches automated techniques are urgently required. We have established an automated, fast and flexible low-cost expression cloning approach requiring only vector and insert amplification by PCR and co-transformation of the products. 相似文献915.
Miriam Bellido Laura Lugo Jorge A Roman-Blas Santos Castañeda Jose R Caeiro Sonia Dapia Emilio Calvo Raquel Largo Gabriel Herrero-Beaumont 《Arthritis research & therapy》2010,12(4):R152-11
Introduction
Osteoporosis (OP) increases cartilage damage in a combined rabbit model of OP and osteoarthritis (OA). Accordingly, we assessed whether microstructure impairment at subchondral bone aggravates cartilage damage in this experimental model. 相似文献916.
Libersou S Albertini AA Ouldali M Maury V Maheu C Raux H de Haas F Roche S Gaudin Y Lepault J 《The Journal of cell biology》2010,191(1):199-210
The entry of enveloped viruses into cells requires the fusion of viral and cellular membranes, driven by conformational changes in viral glycoproteins. Many studies have shown that fusion involves the cooperative action of a large number of these glycoproteins, but the underlying mechanisms are unknown. We used electron microscopy and tomography to study the low pH-induced fusion reaction catalyzed by vesicular stomatitis virus glycoprotein (G). Pre- and post-fusion crystal structures were observed on virions at high and low pH, respectively. Individual fusion events with liposomes were also visualized. Fusion appears to be driven by two successive structural rearrangements of G at different sites on the virion. Fusion is initiated at the flat base of the particle. Glycoproteins located outside the contact zone between virions and liposomes then reorganize into regular arrays. We suggest that the formation of these arrays, which have been shown to be an intrinsic property of the G ectodomain, induces membrane constraints, achieving the fusion reaction. 相似文献
917.
The house fly, Musca domestica L. (Diptera: Muscidae), continues to be a primary pest of livestock facilities worldwide. This pest also has shown a propensity for pesticide resistance development when under high selection pressures. In this study the house fly strain FDm was created by a 20% contribution from each of five colonies collected from dairies in Florida with known imidacloprid resistance. The FDm strain was used to evaluate the level ofimidacloprid resistance after five selections near the LC70 value of each selected generation. Overall, the mean selection mortality was 72.7, with males being considerably more susceptible than females. The unselected (F0) FDm strain showed considerable susceptibility to imidacloprid after its creation, compared with the five parental strains. Between 9500 and 14,000 virgin house flies were used in each selection. After the fifth and final selection, a 331-fold increase in imidacloprid resistance at the LC70 was observed over the parental FDm strain. In parallel studies, the FDm strain showed increasing tolerance of the commercial imidacloprid product QuickBayt. These results suggest that livestock producers should use caution when choosing pesticides and consider rotating fly baits, as is encouraged with other pesticide treatment regimes on farms. 相似文献
918.
919.
Anna Kuparinen Jarle Tufto Sonia Consuegra Kjetil Hindar Juha Meril? Carlos Garcia de Leaniz 《Conservation Genetics》2010,11(4):1559-1565
The genetic diversity of metapopulations is influenced not only by the effective sizes (N
e
) of individual subpopulations, but also by the total effective size of the metapopulation (meta-N
e
). We estimated meta-N
e
of four neighbouring Atlantic salmon populations connected by gene flow using genetic estimates of subpopulation N
e
s and migration rates derived from capture–recapture data. The meta-[^(N)]e meta{\hbox{-}}\hat{N}_{e} was lower than the sum of [^(N)]e \hat{N}_{e} s of the subpopulations, suggesting that genetic diversity harboured by the four river salmon metapopulation is lower than
what would have been expected by viewing individual subpopulations separately. In addition, meta-[^(N)]e meta{\hbox{-}}\hat{N}_{e} was found to be sensitive to changes in [^(N)]e \hat{N}_{e} of the subpopulation from which net emigration rate was largest, so as that the genetic diversity of the metapopulation would
be best preserved by avoiding any reductions in N
e
of this subpopulation. Yet, this subpopulation is the one that has historically—and still is—experiencing the highest exploitation
rate in the metapopulation system. 相似文献
920.
Maria Cristiane Martins de Souza Igor Tadeu Lazzarotto Bresolin Sonia Maria Alves Bueno 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(5-6):557-566
The ω-aminohexyl diamine immobilized as ligand on CNBr- and bisoxirane-activated agarose gel was evaluated for the purification of human immunoglobulin G (IgG) from serum and plasma by negative affinity chromatography. The effects of matrix activation, buffer system, and feedstream on recovery and purity of IgG were studied. A one-step purification process using Hepes buffer at pH 6.8 allowed a similar recovery (69–76%) of the loaded IgG in the nonretained fractions for both matrices, but the purity was higher for epoxy-activated gel (electrophoretically homogeneous protein with a 6.5-fold purification). The IgG and human serum albumin (HSA) adsorption equilibrium studies showed that the adsorption isotherms of IgG and HSA obeyed the Langmuir–Freundlich and Langmuir models, respectively. The binding capacity of HSA was high (210.4 mg mL?1 of gel) and a positive cooperativity was observed for IgG binding. These results indicate that immobilizing ω-aminohexyl using bisoxirane as coupling agent is a useful strategy for rapid purification of IgG from human serum and plasma. 相似文献