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971.
972.
973.
Qiongbo Hu Shuyan Liu Fei Yin Shujia Cai Guohua Zhong Shunxiang Ren 《Biocontrol Science and Technology》2011,21(2):225-234
To comprehend the diversity and potential control of soil-dwelling fungi, Isaria and Paecilomyces, against the red imported fire ant Solenopsis invicta (Hymenoptera, Formicidae), an investigation was carried out between 2004 and 2008. From 258 soil samples collected from 16 central and southern provinces and cities in China, a total of 171 isolates of the genra Isaria and Paecilomyce were isolated, and the species I. javanicus, P. marquandii and I. fumosoroseus were found more abundant than I. cateniobliquus, P. carneus, P. inflatus and P. lilacinus. Geographic differences of isolating rates were observed as well. Samples from the southern areas had higher fungal isolating rates than those from the central areas. Subsequently, 47 isolates were further tested for pathogencity against the red imported fire ant. All isolates except P115 showed certain pathogenic potential (the mean is 52.3% at 4000 conidiospores/mL) to the ant. I. javanicus was the most effective species with a mean pathogenicity of 80.6%, while pathogenicities of P. marquandii, P. gunni and I. fumosoroseus were 44, 21 and 49%, respectively. Furthermore, the more effective isolates P028 of I. javanicus and P003 of I. fumosoroseus were tested in a virulence experiment. The LD50 values of P028 and P003 against major and miner workers were determined as 412,280 and 854,451 conidiospores/cm2, respectively. Meanwhile, the LT50 values at 1000 conidiospores/cm2 were 7.1 and 6.6 d in isolate P003 and 6.8 and 6.6 d in isolate P028. 相似文献
974.
A versatile and highly sensitive probe for Hg(II), Pb(II) and Cd(II) detection individually and totally in water samples 总被引:1,自引:0,他引:1
Zhou Y Tian XL Li YS Zhang YY Yang L Zhang JH Wang XR Lu SY Ren HL Liu ZS 《Biosensors & bioelectronics》2011,30(1):310-314
The detection of heavy metal ions using enzyme-linked immunosorbent assays (ELISA) has been reported by several research groups. However, highly sensitive and selective detection of total heavy metal ions using ELISA is a major technical limitation. Here we describe the development of a versatile and highly sensitive probe combining goat anti-mice IgG, colloidal gold nanoparticles (AuNPs) and horseradish peroxidase (HRP). We demonstrate the utility of this probe using three kinds of heavy metal complete antigens and three monoclonal antibodies (McAbs) in one ELISA system to establish a high-throughput screening protocol. The procedure was successfully applied to analysis of Hg(II), Pb(II) and Cd(II) individually and totally from different water samples. The sensitivities for the detection of Hg(II), Pb(II) and Cd(II) individually and totally are 27.4, 3.9, 15.8 and 18.2 nM, respectively. And all limit of detection (LODs) are lower than 1.2 nM. The recovery results obtained from the developed technique showed a good correlation (R2 = 0.983) with those from ICP-MS. The major advantage of the probe is the versatility and high sensibility. The probe could be potentially used, upon demand, as a sensitive and versatile detector for a broad range of applications. 相似文献
975.
976.
Zhou Y Tian XL Li YS Pan FG Zhang YY Zhang JH Yang L Wang XR Ren HL Lu SY Li ZH Chen QJ Liu ZS Liu JQ 《Biosensors & bioelectronics》2011,26(8):3700-3704
A novel probe based on colloidal gold nanoparticles (AuNPs) modified with goat anti-mouse IgG and horseradish peroxidase (HRP) was synthesized and an enhanced enzyme-linked immunosorbent assay (ELISA) based on the probe was developed. In the assay, the synthesized probe is bound with a monoclonal antibody (McAb) which is competitively bound by coated BSA-ITCBE-Pb(II) on plate and Pb(II) in samples. The HRP, used here for signal amplification catalytically oxidize the substrate and generate optical signals that is related to the concentration of Pb(II) and can be measured spectrophotometrically. For the monodisperse AuNPs having high surface areas, it can be conjugated with more amount of HRP than that of IgG. Therefore, compared with traditional ELISA, the signal amplification of catalytically oxidized substrate was enhanced. The detection limit for this novel modified AuNPs probe-based assay was 9 pg mL(-1). The recoveries obtained by standard Pb(II) addition to real samples, including a commercial mineral water, tap water, and lake water were all from 94.9% to 102.9%. And the coefficient of variation (CV) value of all samples was less than 10%. The results indicated that the enhanced assay gave higher sensitivity and reliable reproducibility. It could provide a general detection format for low-molecular weight contaminants. 相似文献
977.
In this paper, we developed a simple method to detect fungi toxin (ochratoxin A) produced by Aspergillus Ochraceus and Penicillium verrucosumm, utilizing graphene oxide as quencher which can quench the fluorescence of FAM (carboxyfluorescein) attached to toxin-specific aptamer. By optimizing the experimental conditions, we obtained the detection limit of our sensing platform based on bare graphene oxide to be 1.9 μM with a linear detection range from 2 μM to 35 μM. Selectivity of this sensing platform has been carefully investigated; the results showed that this sensor specifically responded to ochratoxin A without interference from other structure analogues (N-acetyl-l-phenylalanine and warfarin) and with only limited interference from ochratoxin B. Experimental data showed that ochratoxin A as well as other structure analogues could adsorb onto the graphene oxide. As compared to the non-protected graphene oxide based biosensor, PVP-protected graphene oxide reveals much lower detection limit (21.8 nM) by two orders of magnitude under the optimized ratio of graphene oxide to PVP concentration. This sensor has also been challenged by testing 1% red wine containing buffer solution spiked with a series of concentration of ochratoxin A. 相似文献
978.
von der Lieth CW Freire AA Blank D Campbell MP Ceroni A Damerell DR Dell A Dwek RA Ernst B Fogh R Frank M Geyer H Geyer R Harrison MJ Henrick K Herget S Hull WE Ionides J Joshi HJ Kamerling JP Leeflang BR Lütteke T Lundborg M Maass K Merry A Ranzinger R Rosen J Royle L Rudd PM Schloissnig S Stenutz R Vranken WF Widmalm G Haslam SM 《Glycobiology》2011,21(4):493-502
The EUROCarbDB project is a design study for a technical framework, which provides sophisticated, freely accessible, open-source informatics tools and databases to support glycobiology and glycomic research. EUROCarbDB is a relational database containing glycan structures, their biological context and, when available, primary and interpreted analytical data from high-performance liquid chromatography, mass spectrometry and nuclear magnetic resonance experiments. Database content can be accessed via a web-based user interface. The database is complemented by a suite of glycoinformatics tools, specifically designed to assist the elucidation and submission of glycan structure and experimental data when used in conjunction with contemporary carbohydrate research workflows. All software tools and source code are licensed under the terms of the Lesser General Public License, and publicly contributed structures and data are freely accessible. The public test version of the web interface to the EUROCarbDB can be found at http://www.ebi.ac.uk/eurocarb. 相似文献
979.
Estimation of a novel method to produce bio-oil from sewage sludge by microwave pyrolysis with the consideration of efficiency and safety 总被引:2,自引:0,他引:2
This paper presented a feasible method to produce bio-oil from sewage sludge by microwave pyrolysis. The results showed that oils derived under 400 W obtained an attractive yield (49.8 wt.%) with favorable characteristics such as high calorific value (35.0 MJ/kg), low density (929 kg/m3) and preferable chemical composition (29.5 wt.% of monoaromatics). A model to study the relationship between microwave power and mass balance of product fractions was developed, and the results indicated that the power range of the highest transforming efficiency for organics in sludge into oils was 400-600 W, the subsequent increase of power to the range of 600-800 W favored gases formation at the expense of oils, and increase of power to above 800 W led to the conversion of solids into gases, while oils remained unchanged. The analysis of sulfur and nitrogen compounds in oils showed that bio-oil should be extracted before being used as fuel. 相似文献
980.
The biosorption of tetradecyl benzyl dimethyl ammonium chloride (C14BDMA) onto activated sludge was examined in aqueous solution with respect to the contact time, temperature and particle size. Equilibrium reached in about 2 h contact time. An decrease in the temperature increases of biosorption capacity of C14BDMA onto activated sludge, which also increases with decreasing particle size. The experimental data fit the pseudo-second-order kinetics model well. The Langmuir and Freundlich models were applied to describe equilibrium isotherms, and the equilibrium partitioning data was described well by both models. Thermodynamic data showed that C14BDMA biosorption onto activated sludge was feasible, spontaneous and exothermic. The Fourier transform infrared (FT-IR) spectrophotometry results show that both physisorption and chemisorption were involved. The measured zeta potential values and the enhanced cation concentration indicate the presence of electrostatic interactions, hydrophobic interactions and ion exchange. 相似文献