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81.
Menthol mint (Mentha arvensis L.) cultivation is significantly affected by the heavy metals like cadmium (Cd) which also imposes severe health hazards. Two menthol mint cultivars namely Kosi and Kushal were evaluated under Cd stress conditions. Impact of plant growth regulators (PGRs) like salicylic acid (SA), gibberellic acid (GA3) and triacontanol (Tria) on Cd stress tolerance was assessed. Reduced growth, photosynthetic parameters, mineral nutrient concentration, and increased oxidative stress biomarkers like electrolyte leakage, malondialdehyde, and hydrogen peroxide contents were observed under Cd stress. Differential upregulation of proline content and antioxidant activities under Cd stress was observed in both the cultivars. Interestingly, low electrolyte leakage, lipid peroxidation, hydrogen peroxide and Cd concentration in leaves were observed in Kushal compared to Kosi. Among all the PGRs tested, SA proved to be the best in improving Cd-stress tolerance in both the cultivars but Kushal responded better than Kosi.  相似文献   
82.
Chitin is an organic polymer and it is the most frequent marine natural polysaccharide after cellulose. The main natural sources of chitin are exoskeletons of insects, mollusks, the cell walls of certain fungi and crustaceans such as crabs, shrimps and lobsters. The waste of these marine exoskeletons are pollutant for the environment, but these waste raw materials could be useful for production of commercial products like chitin. Chitin is an important raw material used for water treatment, agricultural, biomedical, biotechnological purposes, food and paper industry and cosmetics. Based on the variety of importance, the present targets of this study are to optimize the demineralization process for the removal of calcium and phosphate contents from the waste of Portunidae segnis (P. segnis) by using acid at ambient temperature and to characterize the isolated demineralized sample as well as the percentage of remaining calcium and phosphorus contents by using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The prepared waste carbs coarse powder samples of P. segnis were demineralized with seven different concentrations of hydrochloric acid at ambient temperature for 1 h. All the demineralization samples by the different concentrations were analyzed by using sensitive ICP-OES. The results based on ICP-OES showed that among the seven different concentrations used in the demineralization process for the isolation of chitin, the best was 2 M of HCl concentration for the production of chitin. The results also showed that the optimized concentration 2 M HCl gave the minimum concentration of calcium and phosphorus compared to other concentrations applied in this experiment. In conclusion, the optimized concentration for demineralization process could be used commercially for the isolation or commercial production of chitin for agricultural, biomedical and biotechnological purposes.  相似文献   
83.
Globally among biotic stresses, diseases like blight, rust and blast constitute prime constraints for reducing wheat productivity especially in Bangladesh. For sustainable productivity, the development of disease-resistant lines and high yielding varieties is vital and necessary. This study was conducted using 122 advanced breeding lines of wheat including 21 varieties developed by Bangladesh Wheat and Maize Research Institute (BAMRI) with aims to identify genotypes having high yield potential and resistance to leaf blight, leaf rust and blast diseases. These genotypes were evaluated for resistance against leaf blight and leaf rust at Dinajpur and wheat blast at Jashore under field condition. Out of 122 genotypes tested, 20 lines were selected as resistant to leaf blight based on the area under the diseases progress curve (AUDPC) under both irrigated timely sown (ITS) and irrigated late sown (ILS) conditions. Forty-two genotypes were found completely free from leaf rust infection, 59 genotypes were identified as resistant, and 13 genotypes were identified as moderately resistant to leaf rust. Eighteen genotypes were immune against wheat blast, 42 genotypes were categorized as resistant, and 26 genotypes were identified as moderately resistant to wheat blast. Molecular data revealed that the 16 genotypes showed a positive 2NS segment among the 18 immune genotypes selected against wheat blast under field conditions. The genotypes BAW 1322, BAW 1295, and BAW 1203 can be used as earlier maturing genotypes and the genotypes BAW 1372, BAW 1373, BAW 1297 and BAW 1364 can be used for lodging tolerant due to short plant height. The genotypes WMRI Gom 1, BAW 1349 and BAW 1350 can be selected for bold grain and the genotypes WMRI Gom 1, BAW 1297, BAW 1377 can be used as high yielder for optimum seeding condition but genotypes BAW 1377 and BAW 1366 can be used for late sown condition. The selected resistant genotypes against specific diseases can be used in the further breeding program to develop wheat varieties having higher disease resistance and yield potential.  相似文献   
84.
Objectives

Epitope-driven vaccines carrying highly conserved and immunodominant epitopes have emerged as promising approaches to overcome human immunodeficiency virus-1 (HIV-1) infection.

Methods

Two multiepitope DNA constructs encoding T cell epitopes from HIV-1 Gag, Pol, Env, Nef and Rev proteins alone and/or linked to the immunogenic epitopes derived from heat shock protein 70 (Hsp70) as an immunostimulatory agent were designed. In silico analyses were applied including MHC-I and MHC-II binding, MHC-I immunogenicity and antigen processing, population coverage, conservancy, allergenicity, toxicity and hemotoxicity. The peptide-MHC-I/MHC-II molecular docking and cytokine production analyses were carried out for predicted epitopes. The selected highly immunogenic T-cell epitopes were then used to design two multiepitope fusion constructs. Next, prediction of the physicochemical and structural properties, B cell epitopes, and constructs-toll-like receptors (TLRs) molecular docking were performed for each construct. Finally, the eukaryotic expression plasmids harboring totally 12 cytotoxic T Lymphocyte (CTL) and 10 helper T lymphocytes (HTL) epitopes from HIV-1 proteins (i.e., pEGFP-N1-gag-pol-env-nef-rev), and linked to 2 CTL and 2 HTL epitopes from Hsp70 (i.e., pEGFP-N1-hsp70-gag-pol-env-nef-rev) were generated and transfected into HEK-293 T cells for evaluating the percentage of multiepitope peptides expression using flow cytometry and western blotting.

Results

The designed DNA constructs could be successfully expressed in mammalian cells. The expression rates of Gag-Pol-Env-Nef-Rev-GFP and Hsp70-Gag-Pol-Env-Nef-Rev-GFP were about 56–60% as the bands of?~?63 and?~?72 kDa confirmed in western blotting, respectively.

Conclusion

The combined in silico/in vitro methods indicated two multiepitope constructs can be produced and used as probable effective immunogens for HIV-1 vaccine development.

  相似文献   
85.
86.
Molecular Biology Reports - Monoclonal antibodies (mAbs) are widely employed as invaluable therapeutics for a vast number of human disorders. Several approaches have been introduced for the...  相似文献   
87.
Molecular Biology Reports - Combination therapy has been considered as a potential method to overcome the BC chemoresistance. MicroRNAs (miRs) have been suggested as a therapeutic factor in the...  相似文献   
88.
Molecular Biology Reports - Autophagy process is an important defense mechanism against intracellular infection. This process plays a critical role in limiting the development of Toxoplasma gondii....  相似文献   
89.
Background

Strawberry crinkle virus (SCV) is a member of the genus Cytorhabdovirus, family Rhabdovirida, and order Mononegavirales. SCV affects the production of various strawberry cultivars. In this study we investigated the genetic diversity of SCV in strawberry fields based on P3 (movement protein) gene.

Methods and results

The samples were collected from strawberry fields in the Kurdistan Province, Iran. P3 gene from 20 SCV isolates, representing 18 nucleic acid haplotypes, is composed of 729 nucleotides, encoding a protein with 243 amino acids. SCV-P3 sequences shared 98.77%–99.86% nucleotide and 97.5%–100% amino acid sequence identity. Phylogenetic analyses of the new P3 sequences with two previously published SCV-P3 sequences from the Czech Republic showed that there are two major phylogroups (I and II) and three minor phylogroups in the body of the phylogeny, I-1, I-2, II-1. Comparisons of P3 gene sequences revealed a mutational bias, with more differences being transitions than transversions. The ratio of non-synonymous/synonymous nucleotide changes was?<?1, indicating that SCV-P3 gene is under predominantly negative selection.

Conclusions

Phylogenetic and sequence identity analyses showed that SCV isolates from Iran are closely related and have not diverged more than 2% based on P3 gene despite geographical separation and strawberry cultivar. This is the first report of the genetic diversity of SCV worldwide.

  相似文献   
90.
Molecular Biology Reports - Hepatocellular carcinoma (HCC) is the most common primary liver cancer characterized by dysregulation of several crucial cellular signaling pathways such as...  相似文献   
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