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991.
In order to distinguish between the mechanism of microsomal ethanol oxidation and hydroxyl-radical formation, the rate of cytochrome P-450 (P-450)-dependent oxidation of dimethyl sulphoxide (Me2SO) was determined in the presence and in the absence of iron-chelating compounds, in liver microsomes from control, ethanol- and phenobarbital-treated rats. Ethanol treatment resulted in a specific increase (3-fold) of the microsomal ethanol oxidation and NADPH consumption per nmol of P-450. A form of P-450 was purified to apparent homogeneity from the ethanol-treated rats and characterized with respect of amino acid composition and N-terminal amino acid sequence. Specific ethanol induction of a cytochrome P-450 species having a catalytic-centre activity of 20/min for ethanol and consuming 30 nmol of NADPH/min could account for the results observed with microsomes. Phenobarbital treatment caused 50% decrease in the rate of ethanol oxidation and NADPH oxidation per nmol of P-450. The rate of oxidation of the hydroxyl-radical scavenger Me2SO was increased 3-fold by ethanol or phenobarbital treatment when expressed on a per-mg-of-microsomal-protein basis, but the rate of Me2SO oxidation expressed on a per-nmol-of-P-450 basis was unchanged. Addition of iron-chelating agents to the three different types of microsomal preparations caused an 'uncoupling' of the electron-transport chain accompanied by a 4-fold increase of the rate of Me2SO oxidation. It is concluded that ethanol treatment results in the induction of P-450 forms specifically effective in ethanol oxidation and NADPH oxidation, but not in hydroxyl-radical production, as detected by the oxidation of Me2SO.  相似文献   
992.
993.
Mesoporous bioactive nanoparticles (MBNs) have been developed as promising additives to various types of bone or dentin regenerative material. However, biofunctionality of MBNs as dentin regenerative additive to dental materials have rarely been studied. We investigated the uptake efficiency of MBNs-NH2 with their endocytosis pathway and the role of MBNs-NH2 in odontogenic differentiation to clarify inherent biofunctionality. MBNs were fabricated by sol-gel synthesis, and 3% APTES was used to aminate these nanoparticles (MBNs-NH2) to reverse their charge from negative to positive. To characterize the MBNs-NH2, TEM, XRD, FTIR, zeta(ξ)-potential measurements, and Brunauer–Emmett–Teller analysis were performed. After primary cultured rat dental pulp stem cells (rDPSCs) were incubated with various concentrations of MBNs-NH2, stem cell viability (24 hours) with or without differentiated media, internalization of MBNs-NH2 in rDPSCs (~4 hours) via specific endocytosis pathway, intra or extracellular ion concentration and odontoblastic differentiation (~28 days) were investigated. Incubation with up to 50 μg/mL of MBNs-NH2 had no effect on rDPSCs viability with differentiated media (p>0.05). The internalization of MBNs-NH2 in rDPSCs was determined about 92% after 4 hours of incubation. Uptake was significantly decreased with ATP depletion and after 1 hour of pre-treatment with the inhibitor of macropinocytosis (p<0.05). There was significant increase of intracellular Ca and Si ion concentration in MBNs-NH2 treated cells compared to no-treated counterpart (p<0.05). The expression of odontogenic-related genes (BSP, COL1A, DMP-1, DSPP, and OCN) and the capacity for biomineralization (based on alkaline phosphatase activity and alizarin red staining) were significantly upregulated with MBNs-NH2. These results indicate that MBNs-NH2 induce odontogenic differentiation of rDPSCs and may serve as a potential dentin regenerative additive to dental material for promoting odontoblast differentiation.  相似文献   
994.
Human umbilical cord blood derived CD34+ stem cells are reported to mediate therapeutic effects in stroke animal models. Estrogen was known to protect against ischemic injury. The present study wished to investigate whether the protective effect of CD34+ cells against ischemic injury can be reinforced with complemental estradiol treatment in female ovariectomized rat and its possible mechanism. Experiment 1 was to determine the best optimal timing of CD34+ cell treatment for the neuroprotective effect after 60-min middle cerebral artery occlusion (MCAO). Experiment 2 was to evaluate the adjuvant effect of 17β-estradiol on CD34+ cell neuroprotection after MCAO. Experiment 1 showed intravenous infusion with CD34+ cells before MCAO (pre-treatment) caused less infarction size than those infused after MCAO (post-treatment) on 7T magnetic resonance T2-weighted images. Experiment 2 revealed infarction size was most significantly reduced after CD34+ + estradiol pre-treatment. When compared with no treatment group, CD34+ + estradiol pre-treatment showed significantly less ADC reduction at 2 h and 2 d, less CBF reduction at 2 h and less hyperperfusion at 2 d. The immunoreactivity of c-Fos, c-Jun and GFAP was attenuated, and BDNF showed significant recovery from 2 h to 2 d after MCAO, especially after CD34+ + estradiol pre-treatment. The present study suggests pre-treatment with CD34+ cells with complemental estradiol can be most protective against ischemic injury, which may act through stabilization of cerebral hemodynamics and normalization of the expressions of immediate early genes and BDNF.  相似文献   
995.
In the present study, we investigated the role of Paeonia lactiflora Pall. extract on embryo implantation in vitro and in vivo. A polysaccharides depleted-water extract of P. lactiflora (PL-PP) increased LIF expression in human endometrial Ishikawa cells at non-cytotoxic doses. PL-PP significantly increased the adhesion of the human trophectoderm-derived JAr spheroids to endometrial Ishikawa cells. PL-PP-induced LIF expression was decreased in the presence of a p38 kinase inhibitor SB203580 and an MEK/ERK inhibitor U0126. Furthermore, endometrial LIF knockdown by shRNA reduced the expression of integrins β3 and β5 and adhesion of JAr spheroids to Ishikawa cells. In vivo administration of PL-PP restored the implantation of mouse blastocysts in a mifepristone-induced implantation failure mice model. Our results demonstrate that PL-PP increases LIF expression via the p38 and MEK/ERK pathways and favors trophoblast adhesion to endometrial cells.  相似文献   
996.
The causative agent of White-nose Syndrome (WNS), Pseudogymnoascus destructans, has been shown to be fatal to several species of bats in North America. To date, no compounds or chemical control measures have been developed which eliminates the growth of the fungus in the environment or in affected animals. In the current study, we evaluated the activity of cold-pressed, terpeneless orange oil (CPT) against multiple isolates of P. destructans in vitro. For all assays, a modified Kirby-Bauer disk diffusion assay was used. Standardized spore suspensions were prepared, adjusted to a specific optical density, and used to plate fungal lawns. Plates were incubated at either 15°C or 4°C for up to 6 months and checked at regular intervals for growth. Once controls had grown, zones of inhibition were measured (mm) on test plates and compared to those obtained using current antifungal drugs. All P. destructans isolates were completely inhibited by 100% CPT (10 μL) at 1 month of incubation regardless of temperature (4°C and 15°C). Complete inhibition persisted up to 6 months following a single exposure at this concentration. Of the standard antifungals, only amphotericin B demonstrated any activity, resulting in zone diameters ranging from 58 mm to 74 mm. CPT, at the highest concentration tested (100%), had no significant effect against a variety of other environmental organisms including various filamentous fungi, bacteria and aerobic actinomycetes. Given that CPT is relatively non-toxic, the possibility exists that the all-natural, mixture could be used as an environmental pre-treatment to eradicate P. destructans from bat habitats. Additional studies are needed to assess any undesirable effects of CPT on bat behavior and health and overall impacts on other members of the interconnected ecosystem(s).  相似文献   
997.
Prebiotics are non-digestible carbohydrate dietary supplements that selectively stimulate the growth of one or more beneficial bacteria in the gastrointestinal tract of the host. These bacteria can inhibit colonization of pathogenic bacteria by producing antimicrobial substances such as short chain fatty acids (SCFAs) and competing for niches with pathogens within the gut. Pasture flock chickens are generally raised outdoors with fresh grass, sunlight and air, which represents different environmental growth conditions compared to conventionally raised chickens. The purpose of this study was to evaluate the difference in microbial populations from naked neck chicken ceca fed with commercial prebiotics derived from brewer’s yeast cell wall via an Illumina MiSeq platform. A total of 147 day-of-hatch naked neck chickens were distributed into 3 groups consisted of 1) C: control (no prebiotic), 2) T1: Biolex® MB40 with 0.2%, and 3) T2: Leiber® ExCel with 0.2%, consistently supplemented prebiotics during the experimental period. At 8 weeks, a total of 15 birds from each group were randomly selected and ceca removed for DNA extraction. The Illumina Miseq platform based on V4 region of 16S rRNA gene was applied for microbiome analysis. Both treatments exhibited limited impact on the microbial populations at the phylum level, with no significant differences in the OTU number of Bacteroidetes among groups and an increase of Proteobacteria OTUs for the T1 (Biolex® MB40) group. In addition there was a significant increase of genus Faecalibacterium OTU, phylum Firmicutes. According to the development of next generation sequencing (NGS), microbiome analysis based on 16S rRNA gene proved to be informative on the prebiotic impact on poultry gut microbiota in pasture-raised naked neck birds.  相似文献   
998.
Cystic fibrosis results from mutations in the cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-dependent protein kinase A (PKA) and ATP-regulated chloride channel. Here, we demonstrate that nucleoside diphosphate kinase B (NDPK-B, NM23-H2) forms a functional complex with CFTR. In airway epithelia forskolin/IBMX significantly increases NDPK-B co-localisation with CFTR whereas PKA inhibitors attenuate complex formation. Furthermore, an NDPK-B derived peptide (but not its NDPK-A equivalent) disrupts the NDPK-B/CFTR complex in vitro (19-mers comprising amino acids 36–54 from NDPK-B or NDPK-A). Overlay (Far-Western) and Surface Plasmon Resonance (SPR) analysis both demonstrate that NDPK-B binds CFTR within its first nucleotide binding domain (NBD1, CFTR amino acids 351–727). Analysis of chloride currents reflective of CFTR or outwardly rectifying chloride channels (ORCC, DIDS-sensitive) showed that the 19-mer NDPK-B peptide (but not its NDPK-A equivalent) reduced both chloride conductances. Additionally, the NDPK-B (but not NDPK-A) peptide also attenuated acetylcholine-induced intestinal short circuit currents. In silico analysis of the NBD1/NDPK-B complex reveals an extended interaction surface between the two proteins. This binding zone is also target of the 19-mer NDPK-B peptide, thus confirming its capability to disrupt NDPK-B/CFTR complex. We propose that NDPK-B forms part of the complex that controls chloride currents in epithelia.  相似文献   
999.
Hepatitis C virus (HCV) infection-induced oxidative stress is a major risk factor for the development of HCV-associated liver disease. Sulforaphane (SFN) is an antioxidant phytocompound that acts against cellular oxidative stress and tumorigenesis. However, there is little known about its anti-viral activity. In this study, we demonstrated that SFN significantly suppressed HCV protein and RNA levels in HCV replicon cells and infectious system, with an IC50 value of 5.7 ± 0.2 μM. Moreover, combination of SFN with anti-viral drugs displayed synergistic effects in the suppression of HCV replication. In addition, we found nuclear factor erythroid 2-related factor 2 (Nrf2)/HO-1 induction in response to SFN and determined the signaling pathways involved in this process, including inhibition of NS3 protease activity and induction of IFN response. In contrast, the anti-viral activities were attenuated by knockdown of HO-1 with specific inhibitor (SnPP) and shRNA, suggesting that anti-HCV activity of SFN is dependent on HO-1 expression. Otherwise, SFN stimulated the phosphorylation of phosphoinositide 3-kinase (PI3K) leading Nrf2-mediated HO-1 expression against HCV replication. Overall, our results indicated that HO-1 is essential in SFN-mediated anti-HCV activity and provide new insights in the molecular mechanism of SFN in HCV replication.  相似文献   
1000.
Although acupuncture therapy is widely used in traditional Asian medicine for the treatment of diverse internal organ disorders, its underlying biological mechanisms are largely unknown. Here, we investigated the functional involvement of acupuncture stimulation (AS) in the regulation of inflammatory responses. TNF-α production in mouse serum, which was induced by lipopolysaccharide (LPS) administration, was decreased by manual acupuncture (MAC) at the zusanli acupoint (stomach36, ST36). In the spleen, TNF-α mRNA and protein levels were also downregulated by MAC and were recovered by using a splenic neurectomy and a vagotomy. c-Fos, which was induced in the nucleus tractus solitarius (NTS) and dorsal motor nucleus of the vagus nerve (DMV) by LPS and electroacupuncture (EAC), was further increased by focal administration of the AMPA receptor blocker CNQX and the purinergic receptor antagonist PPADS. TNF-α levels in the spleen were decreased by CNQX and PPADS treatments, implying the involvement of inhibitory neuronal activity in the DVC. In unanesthetized animals, both MAC and EAC generated c-Fos induction in the DVC neurons. However, MAC, but not EAC, was effective in decreasing splenic TNF-α production. These results suggest that the therapeutic effects of acupuncture may be mediated through vagal modulation of inflammatory responses in internal organs.  相似文献   
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