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891.
Metabolism and growth in Arabidopsis depend on the daytime temperature but are temperature-compensated against cool nights 总被引:1,自引:0,他引:1
Pyl ET Piques M Ivakov A Schulze W Ishihara H Stitt M Sulpice R 《The Plant cell》2012,24(6):2443-2469
Diurnal cycles provide a tractable system to study the response of metabolism and growth to fluctuating temperatures. We reasoned that the response to daytime and night temperature may vary; while daytime temperature affects photosynthesis, night temperature affects use of carbon that was accumulated in the light. Three Arabidopsis thaliana accessions were grown in thermocycles under carbon-limiting conditions with different daytime or night temperatures (12 to 24 °C) and analyzed for biomass, photosynthesis, respiration, enzyme activities, protein levels, and metabolite levels. The data were used to model carbon allocation and growth rates in the light and dark. Low daytime temperature led to an inhibition of photosynthesis and an even larger inhibition of growth. The inhibition of photosynthesis was partly ameliorated by a general increase in protein content. Low night temperature had no effect on protein content, starch turnover, or growth. In a warm night, there is excess capacity for carbon use. We propose that use of this capacity is restricted by feedback inhibition, which is relaxed at lower night temperature, thus buffering growth against fluctuations in night temperature. As examples, the rate of starch degradation is completely temperature compensated against even sudden changes in temperature, and polysome loading increases when the night temperature is decreased. 相似文献
892.
Vdo C Souza KB Schlemmer CB Noal JA Jaques CE Zimmermann CA Leal J Fleck EA Casali VM Morsch MR Schetinger DB Leal 《Parasitology international》2012,61(4):690-696
Trypanosoma cruzi infection triggers a chronic inflammatory process in human host and purinergic system ecto-enzymes play an important role in modulating the inflammatory and immune responses. In this study, it was investigated ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase; EC 3.6.1.5; CD39) and ecto-adenosine deaminase (E-ADA; EC 3.5.4.4) activities in lymphocytes from patients with indeterminate form of Chagas' disease (IFCD). Twenty-five IFCD patients and 25 healthy subjects (control group) were selected. The peripheral lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Adenine nucleotides and adenosine levels were determined in serum by HPLC and the E-NTPDase1 expression in lymphocytes by Western blot analysis. E-NTPDase (ATP and ADP as substrates) and E-ADA (adenosine as substrate) activities were decreased in lymphocytes from IFCD patients (P<0.05 and P<0.01, respectively), while the E-NTPDase1 expression presented no changes in these patients. Serum ATP levels showed to be decreased (P<0.05) and both AMP (P<0.01) and adenosine (P<0.001) levels were increased in the IFCD group. The enzymatic alterations observed are in agreement with the immune response against T. cruzi infection in IFCD patients, since the decreased extracellular ATP and the increased adenosine levels trigger a Th2 anti-inflammatory response, which it is associated to adaptation of host to parasite, preventing clinical progress of disease. 相似文献
893.
M Fondi V Orlandini G Emiliani MC Papaleo I Maida E Perrin M Vaneechoutte L Dijkshoorn R Fani 《Journal of bacteriology》2012,194(17):4771-4772
We report the draft genome sequence of Acinetobacter venetianus strain RAG-1(T), which is able to degrade hydrocarbons and to synthesize a powerful biosurfactant (emulsan) that can be employed for oil removal and as an adjuvant for vaccine delivery. The genome sequence of A. venetianus RAG-1(T) might be useful for bioremediation and/or clinical purposes. 相似文献
894.
Derenko M Malyarchuk B Denisova G Perkova M Rogalla U Grzybowski T Khusnutdinova E Dambueva I Zakharov I 《PloS one》2012,7(2):e32179
With the aim of uncovering all of the most basal variation in the northern Asian mitochondrial DNA (mtDNA) haplogroups, we have analyzed mtDNA control region and coding region sequence variation in 98 Altaian Kazakhs from southern Siberia and 149 Barghuts from Inner Mongolia, China. Both populations exhibit the prevalence of eastern Eurasian lineages accounting for 91.9% in Barghuts and 60.2% in Altaian Kazakhs. The strong affinity of Altaian Kazakhs and populations of northern and central Asia has been revealed, reflecting both influences of central Asian inhabitants and essential genetic interaction with the Altai region indigenous populations. Statistical analyses data demonstrate a close positioning of all Mongolic-speaking populations (Mongolians, Buryats, Khamnigans, Kalmyks as well as Barghuts studied here) and Turkic-speaking Sojots, thus suggesting their origin from a common maternal ancestral gene pool. In order to achieve a thorough coverage of DNA lineages revealed in the northern Asian matrilineal gene pool, we have completely sequenced the mtDNA of 55 samples representing haplogroups R11b, B4, B5, F2, M9, M10, M11, M13, N9a and R9c1, which were pinpointed from a massive collection (over 5000 individuals) of northern and eastern Asian, as well as European control region mtDNA sequences. Applying the newly updated mtDNA tree to the previously reported northern Asian and eastern Asian mtDNA data sets has resolved the status of the poorly classified mtDNA types and allowed us to obtain the coalescence age estimates of the nodes of interest using different calibrated rates. Our findings confirm our previous conclusion that northern Asian maternal gene pool consists of predominantly post-LGM components of eastern Asian ancestry, though some genetic lineages may have a pre-LGM/LGM origin. 相似文献
895.
Iaffaldano P Viterbo RG Paolicelli D Lucchese G Portaccio E Goretti B Direnzo V D'Onghia M Zoccolella S Amato MP Trojano M 《PloS one》2012,7(4):e35843
Background and Objectives
Natalizumab reduces the relapse rate and magnetic resonance imaging activity in patients with Relapsing-Remitting Multiple Sclerosis (RRMS). So far the influence of natalizumab on cognitive functions and fatigue in MS remains uncertain. The aim of this prospective, open-label, observational study was to evaluate the possible effects of natalizumab on cognition and fatigue measures in RRMS patients treated for up to two years.Methods
Cognitive performances were examined by the Rao''s Brief Repeatable Battery (BRB), the Stroop test (ST) and the Cognitive Impairment Index (CII), every 12 months. Patients who failed in at least 3 tests of the BRB and the ST were classified as cognitively impaired (CI). Fatigue Severity Scale (FSS) was administered every 12 months to assess patient''s self-reported fatigue. One hundred and 53 patients completed 1 and 2 year-natalizumab treatment, respectively.Results
After 1 year of treatment the percentage of CI patients decreased from 29% (29/100) at baseline to 19% (19/100) (p = 0.031) and the mean baseline values of CII (13.52±6.85) and FSS (4.01±1.63) scores were significantly reduced (10.48±7.12, p<0.0001 and 3.61±1.56, p = 0.008). These significant effects were confirmed in the subgroup of patients treated up to two years.Conclusions
These results demonstrate that a short-term NTZ treatment may significantly improve cognitive performances and fatigue in RRMS patients. 相似文献896.
J Vitoriano-Souza Nd Moreira A Teixeira-Carvalho CM Carneiro FA Siqueira PM Vieira RC Giunchetti SA Moura RT Fujiwara MN Melo AB Reis 《PloS one》2012,7(7):e40745
Vaccine adjuvants are substances associated with antigens that are fundamental to the formation of an intense, durable, and fast immune response. In this context, the use of vaccine adjuvants to generate an effective cellular immune response is crucial for the design and development of vaccines against visceral leishmaniasis. The objective of this study was to evaluate innate inflammatory response induced by the vaccine adjuvants saponin (SAP), incomplete Freund's adjuvant (IFA), and monophosphoryl lipid A (MPL). After a single dose of adjuvant was injected into the skin of mice, we analyzed inflammatory reaction, selective cell migration, and cytokine production at the injection site, and inflammatory cell influx in the peripheral blood. We found that all vaccine adjuvants were able to promote cell recruitment to the site without tissue damage. In addition, they induced selective migration of neutrophils, macrophages, and lymphocytes. The influx of neutrophils was notable at 12 h in all groups, but at other time points it was most evident after inoculation with SAP. With regard to cytokines, the SAP led to production of interleukin (IL)-2, IL-6, and IL-4. IFA promoted production of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, IL-6, IL-17, IL-4, and IL-10. We also observed that MPL induced high production of IL-2, TNF-α, and IFN-γ, in addition to IL-6, IL-17, and IL-10. In peripheral blood, values of certain cell populations in the local response changed after stimulation. Our data demonstrate that the three vaccine adjuvants stimulate the early events of innate immune response at the injection site, suggesting their ability to increase the immunogenicity of co-administered antigens. Moreover, this work provides relevant information about elements of innate and acquired immune response induced by vaccine adjuvants administered alone. 相似文献
897.
898.
Brown AN Smith K Samuels TA Lu J Obare SO Scott ME 《Applied and environmental microbiology》2012,78(8):2768-2774
We show here that silver nanoparticles (AgNP) were intrinsically antibacterial, whereas gold nanoparticles (AuNP) were antimicrobial only when ampicillin was bound to their surfaces. Both AuNP and AgNP functionalized with ampicillin were effective broad-spectrum bactericides against Gram-negative and Gram-positive bacteria. Most importantly, when AuNP and AgNP were functionalized with ampicillin they became potent bactericidal agents with unique properties that subverted antibiotic resistance mechanisms of multiple-drug-resistant bacteria. 相似文献
899.
Papaleo MC Fondi M Maida I Perrin E Lo Giudice A Michaud L Mangano S Bartolucci G Romoli R Fani R 《Biotechnology advances》2012,30(1):272-293
The aerobic heterotrophic bacterial communities isolated from three different Antarctic sponge species were analyzed for their ability to produce antimicrobial compounds active toward Cystic Fibrosis opportunistic pathogens belonging to the Burkholderia cepacia complex (Bcc). The phylogenetic analysis performed on the 16S rRNA genes affiliated the 140 bacterial strains analyzed to 15 genera. Just three of them (Psychrobacter, Pseudoalteromonas and Arthrobacter) were shared by the three sponges. The further Random Amplified Polymorphic DNA analysis allowed to demonstrate that microbial communities are highly sponge-specific and a very low degree of genus/species/strain sharing was detected. Data obtained revealed that most of these sponge-associated Antarctic bacteria and belonging to different genera were able to completely inhibit the growth of bacteria belonging to the Bcc. On the other hand, the same Antarctic strains did not have any effect on the growth of other pathogenic bacteria, strongly suggesting that the inhibition is specific for Bcc bacteria. Moreover, the antimicrobial compounds synthesized by the most active Antarctic bacteria are very likely Volatile Organic Compounds (VOCs), a finding that was confirmed by the SPME-GC-MS technique, which revealed the production of a large set of VOCs by a representative set of Antarctic bacteria. The synthesis of these VOCs appeared to be related neither to the presence of pks genes nor the presence of plasmid molecules. The whole body of data obtained in this work indicates that sponge-associated bacteria represent an untapped source for the identification of new antimicrobial compounds and are paving the way for the discovery of new drugs that can be efficiently and successfully used for the treatment of CF infections. 相似文献
900.
Jan Heering Sebastian Kehrloesser Inga Maria Melzer Byung Il Lee Bernd Thiede Volker Dötsch Krishnaraj Rajalingam 《EMBO reports》2017,18(5):733-744
Caspases are key enzymes responsible for mediating apoptotic cell death. Across species, caspase‐2 is the most conserved caspase and stands out due to unique features. Apart from cell death, caspase‐2 also regulates autophagy, genomic stability and ageing. Caspase‐2 requires dimerization for its activation which is primarily accomplished by recruitment to high molecular weight protein complexes in cells. Here, we demonstrate that apoptosis inhibitor 5 (API5/AAC11) is an endogenous and direct inhibitor of caspase‐2. API5 protein directly binds to the caspase recruitment domain (CARD) of caspase‐2 and impedes dimerization and activation of caspase‐2. Interestingly, recombinant API5 directly inhibits full length but not processed caspase‐2. Depletion of endogenous API5 leads to an increase in caspase‐2 dimerization and activation. Consistently, loss of API5 sensitizes cells to caspase‐2‐dependent apoptotic cell death. These results establish API5/AAC‐11 as a direct inhibitor of caspase‐2 and shed further light onto mechanisms driving the activation of this poorly understood caspase. 相似文献