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991.
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Hussin A. Rothan Zulqarnain Mohamed Pottayil G. Sasikumar Ketha Amarnadh Reddy Noorsaadah Abd Rahman Rohana Yusof 《International journal of peptide research and therapeutics》2014,20(3):259-267
Even with the great advances in cancer therapies, cancer remains the major cause of death worldwide. The use of high doses of anti-cancer chemotherapeutic drugs eventually causes the inevitable damage in non-neoplastic cells. New, selective, and more effective drugs are therefore urgently required to fight cancer. In this study, the anticancer activity of new peptide analogues (P1 and P2) derived from natural peptide, protegrin-1 (PG-1) were evaluated against human breast carcinoma cell lines (MCF-7) and human non-neoplastic mammary epithelial cell lines (MCF-10A), human hepatocellular carcinoma cells (HepG2) and Vero cells. The CC50 values of cancer cells were significantly lower (P < 0.01) compared to non-neo-plastic cells after treating with P1 and P2 analogues. The analogues of PG-1 showed lower percentage of Lactate Dehydrogenase release (P < 0.001) from non-neoplastic cells compared to cancer cells and low haemolytic potential (P < 0.001) compared to PG-1. The P1 and P2 analogues were shown to be able to induce cancer cell senescence and apoptosis in a p53-dependent pathway which in turn, induced caspase activities and subsequent cell death. Overall, these results suggested that designing shorter peptides, as well as altering the number and position of positive charged residues in P1 and P2 analogues resulted in reduction of their toxicity to non-neoplastic cells and increased selectivity towards cancer cells. Increased selectivity also suggests its potential use to be developed as delivery vectors in the design of chemotherapeutic anticancer drugs. 相似文献
994.
Volatile Oils from the Aerial Parts of Eremophila maculata and Their Antimicrobial Activity 下载免费PDF全文
Fadia S. Youssef Razan Hamoud Mohamed L. Ashour Abdel Nasser Singab Michael Wink 《化学与生物多样性》2014,11(5):831-841
The essential oils isolated from the fresh flowers, fresh leaves, and both fresh and air‐dried stems of Eremophila maculata (Scrophulariaceae) were characterized by GC‐FID and GC/MS analyses. Sabinene was the major component in most of the oils, followed by limonene, α‐pinene, benzaldehyde, (Z)‐β‐ocimene, and spathulenol. The leaf and flower essential oils showed antibacterial and antifungal activity against five Gram‐positive and four Gram‐negative bacterial strains, multi‐resistant clinical isolates from patients, i.e., methicillin‐resistant Staphylococcus aureus (MRSA), as well as two yeasts. Minimum inhibitory concentrations (MICs) and minimum microbicidal concentrations (MMCs) were between 0.25 and 4 mg/ml. 相似文献
995.
Mohamed H Al-Agamy Atef M Shibl Mohamed M Hafez Mohammad N Al-Ahdal Ziad A Memish Harish Khubnani 《Annals of clinical microbiology and antimicrobials》2014,13(1):1-7
Background
The prevalence of extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) has increased recently. The aim of this study was to further characterise and to assess the occurrence of ESBL-EC in Riyadh, to use pulsed field gel electrophoresis (PFGE) typing to investigate the epidemiology of ESBL-EC and to determine the prevalence of ST131 in ESBL-EC.Methods
A total of 152 E. coli isolates were collected at a tertiary hospital in Riyadh from September 2010 to June 2011. Genotypic and phenotypic methods were used to characterise ESBLs. PFGE was used to determine genetic relatedness. Detection of ST131 and CTX-M-like ESBLs was performed using real-time PCR.Results
Of 152 strains, 31 were positive for ESBLs by phenotypic methods. The bla CTX-M-15 gene was highly prevalent (30/31 strains, 96.77%) among the 31 ESBL-positive E. coli strains. The bla CTX-M-27 gene was detected in one strain. Twenty (64.5%) out of 31 of ESBL-EC were ST131. PFGE revealed 29 different pulsotypes.Conclusions
Our study documented the high prevalence of ESBLs in E. coli isolates, with CTX-M-15 as the predominant ESBL gene. ST131 clone producing CTX-M-15 has a major presence in our hospital. The high prevalence of CTX-M producers was not due to the spread of a single clone. To the best of our knowledge, this study represents the first report of CTX-M-15 and CTX-M-27 β-lactamases and the detection of the ST131 clone in Saudi E. coli isolates. 相似文献996.
997.
Meghavi N. Patel Sushant Lakkadwala Mohamed S. Majrad Elisha R. Injeti Steven M. Gollmer Zahoor A. Shah Sai Hanuman Sagar Boddu Jerry Nesamony 《AAPS PharmSciTech》2014,15(6):1498-1508
The aim of this research was to advance solid lipid nanoparticle (SLN) preparation methodology by preparing glyceryl monostearate (GMS) nanoparticles using a temperature-modulated solidification process. The technique was reproducible and prepared nanoparticles without the need of organic solvents. An anticancer agent, 5-fluorouracil (5-FU), was incorporated in the SLNs. The SLNs were characterized by particle size analysis, zeta potential analysis, differential scanning calorimetry (DSC), infrared spectroscopy, atomic force microscopy (AFM), transmission electron microscopy (TEM), drug encapsulation efficiency, in vitro drug release, and in vitro cell viability studies. Particle size of the SLN dispersion was below 100 nm, and that of redispersed lyophilizates was ~500 nm. DSC and infrared spectroscopy suggested that the degree of crystallinity did not decrease appreciably when compared to GMS. TEM and AFM images showed well-defined spherical to oval particles. The drug encapsulation efficiency was found to be approximately 46%. In vitro drug release studies showed that 80% of the encapsulated drug was released within 1 h. In vitro cell cultures were biocompatible with blank SLNs but demonstrated concentration-dependent changes in cell viability to 5-FU-loaded SLNs. The 5-FU-loaded SLNs can potentially be utilized in an anticancer drug delivery system.KEY WORDS: atomic force microscopy, calorimetry (DSC), FTIR, particle size, solid lipid nanoparticles 相似文献
998.
Terrence H Bell Saad El-Din Hassan Aurélien Lauron-Moreau Fahad Al-Otaibi Mohamed Hijri Etienne Yergeau Marc St-Arnaud 《The ISME journal》2014,8(2):331-343
Phytoremediation is an attractive alternative to excavating and chemically treating contaminated soils. Certain plants can directly bioremediate by sequestering and/or transforming pollutants, but plants may also enhance bioremediation by promoting contaminant-degrading microorganisms in soils. In this study, we used high-throughput sequencing of bacterial 16S rRNA genes and the fungal internal transcribed spacer (ITS) region to compare the community composition of 66 soil samples from the rhizosphere of planted willows (Salix spp.) and six unplanted control samples at the site of a former petrochemical plant. The Bray–Curtis distance between bacterial communities across willow cultivars was significantly correlated with the distance between fungal communities in uncontaminated and moderately contaminated soils but not in highly contaminated (HC) soils (>2000 mg kg−1 hydrocarbons). The mean dissimilarity between fungal, but not bacterial, communities from the rhizosphere of different cultivars increased substantially in the HC blocks. This divergence was partly related to high fungal sensitivity to hydrocarbon contaminants, as demonstrated by reduced Shannon diversity, but also to a stronger influence of willows on fungal communities. Abundance of the fungal class Pezizomycetes in HC soils was directly related to willow phylogeny, with Pezizomycetes dominating the rhizosphere of a monophyletic cluster of cultivars, while remaining in low relative abundance in other soils. This has implications for plant selection in phytoremediation, as fungal associations may affect the health of introduced plants and the success of co-inoculated microbial strains. An integrated understanding of the relationships between fungi, bacteria and plants will enable the design of treatments that specifically promote effective bioremediating communities. 相似文献
999.
Characterization of the Tomato ARF Gene Family Uncovers a Multi-Levels Post-Transcriptional Regulation Including Alternative Splicing 总被引:1,自引:0,他引:1
1000.
Bahaa-eldin E. Abdel Rahim Mohamed Salih Mahfouz Umar Yagoub Yahya M. H. Solan Rashad Mohammed Alsanosy 《PloS one》2014,9(4)