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991.
黄褐油葫芦虫体营养成分与发育阶段的相关性研究 总被引:6,自引:0,他引:6
对黄褐油葫芦不同发育阶段虫体蛋白质、脂肪和矿物质元素等营养成分进行了测定与分析。结果表明该虫为高蛋白低脂肪昆虫,各发育阶段虫体的蛋白含量平均为15.92%,脂肪含量为5.40%,PG值平均为3.45,蛋白质、脂肪含量随着个体发育逐渐增加,但卵期蛋白含量较高。虫体含有7种主要脂肪酸,不饱和脂肪酸达57.3%,其中亚油酸的含量高达25.47%;富含矿物质元素,其中以Ca,Fe,Zn的含量较高,分别为1164,320.3和107.9μgg。5种脂肪酸和8种矿物质元素含量与发育阶段呈负相关。 相似文献
992.
Protein phosphorylation is a ubiquitous post-translational modification critical to many cellular processes. Large-scale unbiased characterization of phosphorylation status remains a major technical challenge in proteomics. In the present work, we evaluate and optimize titania-based affinity enrichment for global profiling of phosphopeptides from complex biological mixtures. We demonstrate that inclusion of glutamic acid in the sample loading buffer substantially reduced nonspecific binding of nonphosphorylated peptides to the titania while retaining the high binding affinity for phosphopeptides. The reduction in nonspecific peptide binding enhanced overall phosphopeptide recovery, ranging from 22 to 85%, and led to substantial improvement in large-scale global profiling. In addition, we observed that the overall identification of phosphopeptides was significantly enhanced by neutral loss-triggered MS (3) scans and respective use of multiple charge- and mass-dependent filtering criteria for MS (2) and MS (3) spectra. In conjunction with strong-cation exchange chromatography (SCX) for prefractionation, a total of 4002 distinct phosphopeptides were identified from SKBr3 breast cancer cells at false-positive rates of 3.7% and 5.5%, respectively, for singly and doubly phosphorylated peptides. 相似文献
993.
994.
An electrochemical technique for the real-time detection of hydrogen peroxide (H2O2) was employed to describe respiratory burst activity (RBA) of phagocytes in plasma which can be used to evaluate the ability of immune system and disease resistance. The method is based upon the electric current changes, by redox reaction on platinum electrode of extracellular hydrogen peroxide (H2O2) released from phagocytes stimulated by the zymosan at 680 mV direct current (d.c.). Compared with the control, activation of respiratory burst by zymosan particles results in a high amperometric response, and a current peak was obtained during the whole monitoring process. The peak current was proved by addition of Cu2+ and other controls, to be the result of intense release of H2O2 from phagocytes. The peak area was calculated and used to evaluate the quantity of effective H2O2, which represents the quantity of H2O2 beyond the clearance of related enzymes in plasma. According to Faraday's law, the phagocytes' ability of prawns to generate effective H2O2 was evaluated from 1.253 x 10(-14) mol/cell to 6.146 x 10(-14) mol/cell, and carp from 1.689 x 10(-15) mol/cell to 7.873 x 10(-15) mol/cell. This method is an acute and quick detection of extracellular effective H2O2 in plasma and reflects the capacity of phagocytes under natural conditions, which could be applied for selecting species and parents with high immunity for breeding in aquaculture. 相似文献
995.
Background
Creutzfeldt-Jakob disease (CJD) is a rare, rapidly progressive fatal central nervous system disorder, which consists of three main catalogues: sporadic, familial, and iatrogenic CJD.Methodology/Principal Findings
In China, the surveillance for CJD started in 2006, covering 12 provincial Centers for Disease Control and Prevention (CDCs) and 15 hospitals. From 2006 to 2010, 624 suspected patients were referred to China CJD surveillance. The epidemiological, clinical and laboratory features of sporadic CJD (sCJD) were analysed. Both groups of probable and possible sCJD showed highest incidences in the population of 60 to 69 year-olds. The most common presenting symptoms were progressive dementia and mental-related symptoms (neurological symptoms including sleeping turbulence, depression, anxiety and stress). Among the four main clinical manifestations, myoclonus was more frequently observed in the probable sCJD patients. About 2/3 of probable sCJD cases showed positive 14-3-3 in CSF and/or periodic sharp wave complexes (PSWC) in electroencephalography (EEG). The presence of myoclonus was significantly closely related with the appearance of PSWC in EEG. Polymorphisms of codon 129 in PRNP of the notified cases revealed a highly predominant M129M genotype in Han Chinese. Among 23 genetic human prion diseases, ten were D178N/M129M Fatal familial insomnia (FFI) and five were T188K genetic CJD (gCJD), possibly indicating a special distribution of gCJD-related mutations in Han Chinese.Conclusion
From the period of 2006 to 2010, 261 patients were diagnosed as sCJD and 23 patients were diagnosed as genetic human prion diseases in China. The epidemiological, clinical and laboratory analysis data were consistent with the characteristics of sporadic CJD, which provide insight into the features of CJD in China. 相似文献996.
Fang Z Li T Wang Q Zhang X Peng H Fang W Hong Y Ge H Xiao Y 《Applied microbiology and biotechnology》2011,89(4):1103-1110
Laccases are blue multicopper oxidases with potential applications in environmental and industrial biotechnology. In this
study, a new bacterial laccase gene of 1.32 kb was obtained from a marine microbial metagenome of the South China Sea by using
a sequence screening strategy. The protein (named as Lac15) of 439 amino acids encoded by the gene contains three conserved
Cu2+-binding domains, but shares less than 40% of sequence identities with all of the bacterial multicopper oxidases characterized.
Lac15, recombinantly expressed in Escherichia coli, showed high activity towards syringaldazine at pH 6.5–9.0 with an optimum pH of 7.5 and with the highest activity occurring
at 45 °C. Lac15 was stable at pH ranging from 5.5 to 9.0 and at temperatures from 15 to 45 °C. Distinguished from fungal laccases,
the activity of Lac15 was enhanced twofold by chloride at concentrations lower than 700 mM, and kept the original level even
at 1,000 mM chloride. Furthermore, Lac15 showed an ability to decolorize several industrial dyes of reactive azo class under
alkalescent conditions. The properties of alkalescence-dependent activity, high chloride tolerance, and dye decolorization
ability make the new laccase Lac15 an alternative for specific industrial applications. 相似文献
997.
Macrophage differentiation and polarization is influenced by, and act on, many processes associated with autoimmunity. However, the molecular mechanisms underlying macrophage polarization in systemic lupus erythematosus (SLE) remain largely debated. We previously demonstrated that macrophage M2b polarization conferred by activated lymphocyte-derived (ALD)-DNA immunization could initiate and propagate murine lupus nephritis. Serum amyloid P component (SAP), a conserved acute-phase protein in mice, has been reported to bind to DNA and modulate immune responses. In this study, murine SAP was shown to promote macrophage-mediated ALD-DNA uptake through binding to ALD-DNA (SAP/ALD-DNA). Moreover, macrophage phenotypic switch from a proinflammatory M2b phenotype induced by ALD-DNA alone to an anti-inflammatory M2a phenotype stimulated with SAP/ALD-DNA were found because of PI3K/Akt-ERK signaling activation. Both in vivo SAP supplements and adoptive transfer of ex vivo programmed M2a macrophages induced by SAP/ALD-DNA into SLE mice could efficiently alleviate lupus nephritis. Importantly, increased IL-10 secretion, accompanied by anti-inflammatory effect exerted by M2a macrophages, was found to predominantly impede macrophage M2b polarization. Furthermore, neutralization of IL-10 notably reduced the suppressive effect of M2a macrophages. Our results demonstrate that binding of SAP to ALD-DNA could switch macrophage phenotypic polarization from proinflammatory M2b to anti-inflammatory M2a via PI3K/Akt-ERK signaling activation, thus exerting protective and therapeutic interventions on murine lupus nephritis. These data provide a possible molecular mechanism responsible for modulation of macrophage polarization in the context of lupus nephritis and open a new potential therapeutic avenue for SLE. 相似文献
998.
Background
Recent genome-wide association studies have identified a number of common variants associated with fasting glucose homeostasis and type 2 diabetes in populations of European origin. This is a replication study to examine whether such associations are also observed in Chinese Hans.Methods
We genotyped nine variants in or near MADD, ADRA2A, CRY2, GLIS3, PROX1, FADS1, C2CD4B, IGF1 and IRS1 in a population-based cohort including 3,210 unrelated Chinese Hans from Beijing and Shanghai.Results
We confirmed the associations of GLIS3-rs7034200 with fasting glucose (beta = 0.07 mmol/l, P = 0.03), beta cell function (HOMA-B) (beta = −3.03%, P = 0.009), and type 2 diabetes (OR [95%CI] = 1.27 [1.09–1.49], P = 0.003) after adjustment for age, sex, region and BMI. The association for type 2 diabetes remained significant after adjusting for other diabetes related risk factors including family history of diabetes, lipid profile, medication information, hypertension and life style factors, while further adjustment for HOMA-B abolished the association. The A-allele of CRY2-rs11605924 was moderately associated with increased risk of combined IFG/type 2 diabetes (OR [95%CI] = 1.15[1.01–1.30], P = 0.04). SNPs in or near MADD, ADRA2A, PROX1, FADS1, C2CD4B, IGF1, and IRS1 did not exhibit significant associations with type 2 diabetes or related glycemic traits (P≥0.10).Conclusions
In conclusion, our results indicate the associations of GLIS3 locus with type 2 diabetes and impaired fasting glucose in Chinese Hans, partially mediated through impaired beta-cell function. In addition, we also found modest evidence for the association of CRY2-rs11605924 with combined IFG/type 2 diabetes. 相似文献999.
1000.
Zhao YY Cheng XL Liu R Ho CC Wei F Yan SH Lin RC Zhang Y Sun WJ 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(21):1945-1953
Rapid resolution liquid chromatography/tandem multi-stage mass spectrometry (RRLC-MS(n)) and rapid resolution liquid chromatography/tandem mass spectrometry (RRLC/MS/MS) methods were developed for the identification and quantification of ergosterol and its metabolites from rat plasma, urine and faeces. Two metabolites (ERG1 and ERG2) were identified by RRLC/MS(n). The concentrations of the ergosterol were determined by RRLC/MS/MS. The separation was performed on an Agilent Zorbax SB-C18 with the mobile phase consisting of methanol and water (containing 0.1% formic acid). The detection was carried out by means of atmospheric pressure chemical ionization mass spectrometry in positive ion mode with multiple reaction monitoring (MRM). Linear calibration curves were obtained in the concentration range of 7-2000, 6-2000 and 8-7500 ng/mL for plasma, urine and faecal homogenate, respectively. The intra- and inter-day precision values (RSD) were below 10%. The method was applied to the pharmacokinetic properties and elimination pathway of ergosterol in rats. 相似文献