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991.
BackgroundYoung women with breast cancer (BC) are not represented in the trials on hypofractionation. In this study we compared outcomes in young patients with BC to their older counterparts treated with hypofractionated radiotherapy (RT) in a regional cancer centre in India.Materials and methodsBetween January 1990 to December 2010, women with BC, treated with hypofractionated RT dose of 35–40 Gy/15#/3 weeks were divided into two groups, ≤ 35 years and > 35 years. Outcomes compared were locoregional recurrence rate (LRR), locoregional recurrence-free survival (LRRFS), disease-free survival (DFS), overall survival (OS) and toxicities. LRRFS, DFS and OS were estimated using the Kaplan-Meier method.ResultsOf total 2244 patients, 359 were ≤ 35 years of age and 1885 were > 35 years. Patient and disease characteristics were comparable between the two groups, except that comorbidities were significantly higher in the > 35 years age group, more patients aged ≤ 35 years had nodal N3 disease, received chemotherapy and RT to internal mammary nodes and more patients in the > 35 years group received hormonal therapy. Median follow up was 10 years (range 1–30 years). LRR and distant metastases were comparable between the two groups. However, synchronous LRR and distant metastases were significantly higher in the ≤ 35 years group 18 (5.1%) as compared to the > 35 years group 39 (2.1%) with p = 0.018. Estimated 10-year LRRFS, DFS and OS were 92% vs. 94% (p = 0.95), 68% vs. 73%(p = 0.058) and 78% vs. 76% (p = 0.10) in ≤ 35 years and > 35 years, respectively. OS for stage 1 was comparable between the two groups. However, for stage 2 and 3 it was 77% vs. 82% (p = 0.048) and 53% vs. 62% (p = 0.045) in the ≤ 35 years and > 35 years group, respectively. Acute and late toxicity were similar in the two groups.ConclusionYoung BC patients had higher LRR and distant metastases. LRRFS, DFS and toxicities were comparable between the two groups. However, OS was poorer in young BC patients with stage 2 and 3 disease.  相似文献   
992.
Atrial natriuretic factor (ANF) receptor guanylate cyclase (ANF-RGC) is a single chain transmembrane-spanning protein, containing both ANF binding and catalytic activities. ANF binding to the extracellular receptor domain activates the cytosolic catalytic domain, generating the second messenger cyclic GMP. Obligatory in this activation process is an intervening transduction step, which is regulated by the binding of ATP to the cyclase. The partial structural motif of the ATP binding domain of the cyclase has been elucidated and has been termed ATP Regulatory Module (ARM). The crystal structures of the tyrosine kinase domains of the human insulin receptor and haematopoietic cell kinase were used to derive a homology-based model of the ARM domain of ANF-RGC. The model identifies the precise configuration of the ATP-binding pocket in the ARM domain, accurately represents its ATP-dependent features, and shows that the ATP-dependent transduction phenomenon is a two-step mechanism. In the first step, ATP binds to its pocket and changes its configuration; in the second step, via an unknown protein kinase, it phosphorylates the cyclase for its full activation.  相似文献   
993.
A simple protocol for obtaining pure, restrictable and amplifiable megabase genomic DNA from oil free seed residue ofPapaver sominiferum, an important oil seed and morphanian alkaloid yielding plant, has been developed. Fixed oil from the dry seeds was completely recovered in an organic solvent and quantified gravimetrically followed by processing of the residual biomass (defatted seed residue) for genomic DNA isolation. The isolated DNA could be cut by a range of restriction enzymes. The method enables simultaneous isolation and recovery of lipids and genomic DNA from the same test sample, thus allowing two independent analyses from a single sample.  相似文献   
994.
The role of functionalized alginate gels as immobilized matrices in production of l (+) lactic acid by Lactobacillus delbrueckii was studied. L. delbrueckii cells immobilized in functionalized alginate beads showed enhanced bead stability and selectivity towards production of optically pure l (+) lactic acid in higher yields (1.74Yp/s) compared to natural alginate. Palmitoylated alginate beads revealed 99% enantiomeric selectivity (ee) in production of l (+) lactic acid. Metabolite analysis during fermentation indicated low by-product (acetic acid, propionic acid and ethanol) formation on repeated batch fermentation with functionalized immobilized microbial cells. The scanning electron microscopic studies showed dense entrapped microbial cell biomass in modified immobilized beads compared to native alginate. Thus the methodology has great importance in large-scale production of optically pure lactic acid.  相似文献   
995.
The present study investigated the pesticide induced adverse health effects, hematological and biochemical alterations among agriculture workers. A cross sectional study of 51 agriculture workers and 54 unexposed subjects was carried out to evaluate hematological and biochemical alterations in blood. Pesticide exposed individuals were reported adverse clinical outcomes, including tingling, muscle pain, headache, skin disease, etc. A significant alterations in the level of hematological parameters, liver and renal dysfunctions markers and lipid profile suggested hematological, hepatic and renal dysfunctions. A significant decrease in the activity of acetylcholinesterase, reduced glutathione, superoxide dismutase, catalase and increased level of lipid peroxidation was also observed in these agriculture workers. Correlation coefficient analysis showed a positive correlation of chronic exposure with most of the hematological and biochemical parameters. The results demonstrate that the chronic exposure of pesticides cause reduction in the acetylcholinesterase activity and enhanced the risk of adverse clinical outcomes in agriculture workers.  相似文献   
996.
997.
CRISPR/Cas9: a promising way to exploit genetic variation in plants   总被引:2,自引:0,他引:2  
Creation of variation in existing gene pool of crop plants is the foremost requirement in crop improvement programmes. Genome editing is a tool to produce knock out of target genes either by introduction of insertion or by deletion that disrupts the function of a specific gene. The CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9) system is the most recent addition to the toolbox of sequence-specific nucleases that includes ZFNs and TALENs. The CRISPR/Cas9 system allows targeted cleavage of genomic DNA guided by a small noncoding RNA, resulting in gene modifications by both non-homologous end joining and homology-directed repair mechanisms. Here, we present an overview of mechanisms of CRISPR, its potential roles in creating variation in germplasm and applications of this novel interference pathway in crop improvement. The availability of the CRISPR/Cas9 system holds promise in facilitating both forward and reverse genetics and will enhance research in crops that lack genetic resources.  相似文献   
998.
Plasma is the most easily accessible source for biomarker discovery in clinical proteomics. However, identifying potential biomarkers from plasma is a challenge given the large dynamic range of proteins. The potential biomarkers in plasma are generally present at very low abundance levels and hence identification of these low abundance proteins necessitates the depletion of highly abundant proteins. Sample pre-fractionation using immuno-depletion of high abundance proteins using multi-affinity removal system (MARS) has been a popular method to deplete multiple high abundance proteins. However, depletion of these abundant proteins can result in concomitant removal of low abundant proteins. Although there are some reports suggesting the removal of non-targeted proteins, the predominant view is that number of such proteins is small. In this study, we identified proteins that are removed along with the targeted high abundant proteins. Three plasma samples were depleted using each of the three MARS (Hu-6, Hu-14 and Proteoprep 20) cartridges. The affinity bound fractions were subjected to gelC-MS using an LTQ-Orbitrap instrument. Using four database search algorithms including MassWiz (developed in house), we selected the peptides identified at <1% FDR. Peptides identified by at least two algorithms were selected for protein identification. After this rigorous bioinformatics analysis, we identified 101 proteins with high confidence. Thus, we believe that for biomarker discovery and proper quantitation of proteins, it might be better to study both bound and depleted fractions from any MARS depleted plasma sample.  相似文献   
999.
Sequence data arising from an increasing number of partial and complete genome projects is revealing the presence of the polyketide synthase (PKS) family of genes not only in microbes and fungi but also in plants and other eukaryotes. PKSs are huge multifunctional megasynthases that use a variety of biosynthetic paradigms to generate enormously diverse arrays of polyketide products that posses several pharmaceutically important properties. The remarkable conservation of these gene clusters across organisms offers abundant scope for obtaining novel insights into PKS biosynthetic code by computational analysis. We have carried out a comprehensive in silico analysis of modular and iterative gene clusters to test whether chemical structures of the secondary metabolites can be predicted from PKS protein sequences. Here, we report the success of our method and demonstrate the feasibility of deciphering the putative metabolic products of uncharacterized PKS clusters found in newly sequenced genomes. Profile Hidden Markov Model analysis has revealed distinct sequence features that can distinguish modular PKS proteins from their iterative counterparts. For iterative PKS proteins, structural models of iterative ketosynthase (KS) domains have revealed novel correlations between the size of the polyketide products and volume of the active site pocket. Furthermore, we have identified key residues in the substrate binding pocket that control the number of chain extensions in iterative PKSs. For modular PKS proteins, we describe for the first time an automated method based on crucial intermolecular contacts that can distinguish the correct biosynthetic order of substrate channeling from a large number of non-cognate combinatorial possibilities. Taken together, our in silico analysis provides valuable clues for formulating rules for predicting polyketide products of iterative as well as modular PKS clusters. These results have promising potential for discovery of novel natural products by genome mining and rational design of novel natural products.  相似文献   
1000.
Summary A study conducted in pots to evaluate the effect of different Mg/Ca ratios (2, 4, 8 and 16) and electrolyte concentrations (20 and 80 meq/l) at SAR 10 in irrigation water on the nutrient uptake and yield of wheat crop in two soils revealed that the average grain and dry matter yields of wheat decreased significantly with an increase in Mg/Ca ratio in irrigation water, but the magnitude of decrease was greater at higher electrolyte concentration than at lower electrolyte concentration. The concentration of Na in both straw and grain of wheat increased and that of K decreased with an increase in Mg/Ca ratio and electrolyte concentration of irrigation water, which led to higher Na/Ca and Na/K ratios in the plant. Further, the concentration of Ca and Mg both in straw as well as in grain increased with increasing electrolyte concentration of the irrigation water. An increasing proportion of Mg in saline irrigation water resulted in decreased concentration of Ca and increased concentration of Mg in both straw and grain of wheat crop. It was also noticed that the increasing proportion of Mg over Ca in the poor quality irrigation water increased the P content of both straw and grain of wheat crop.  相似文献   
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