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MTU 1010 is a high-yielding mega-variety of rice grown extensively in India. However, it does not perform well in soils with low phosphorus (P) levels. With an objective to improve MTU 1010 for tolerance to low soil P, we have transferred Pup1, a major quantitative trait locus (QTL) associated with tolerance from another mega-variety, Swarna, through marker-assisted backcross breeding (MABB). Foreground selection of the F1 and backcross plants was performed with the co-dominant, closely linked CAPS marker, K20-2, while two flanking markers RM28011 and RM28157 were utilized for recombinant selection. At each backcross generation, positive plants were also analyzed with a set of 85 parental polymorphic SSR markers to identify the QTL-positive plants possessing maximum introgression of MTU 1010 genome. At BC2F1, the best backcross plant was selfed to generate BC2F2s. Among them, the plants homozygous for Pup1 (n?=?22) were reconfirmed using the functional marker for Pup1, viz., K46-1, and they were advanced through pedigree method of selection until BC2F6 generation. A total of five elite BC2F6 lines, possessing Pup1 and phenotypically similar to MTU 1010, were screened in the low soil P plot and normal plot (with optimum soil P levels) during wet season, 2016. All the selected lines showed better performance under low P soil with more number of productive tillers, better root system architecture, and significantly higher yield (>?390%) as compared to MTU 1010. Further, under normal soil, the lines were observed to be similar to or better than MTU 1010 for most of the agro-morphological traits and yield. This study represents the successful application of marker-assisted selection for improvement of tolerance to low soil P in a high-yielding Indian rice variety.  相似文献   
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Ovarian carcinomas relate to highest death rate in gynecologic malignancies as absence of symptoms shield the disease in the early stage. Current evidences have been devoted to discovering early effective screening mechanism prior to the onset of clinical symptoms. Therefore, biomarkers are the crucial tools that are capable of predicting progression, risk stratification and overall therapeutic benefit to fight against this deadly disease. Although recent studies have revealed serum protein markers, CA-125, HE4, mesothelin etc. have higher sensitivity and specificity at the early stages of the cancer; the critical questions arise regarding the applicability and reproducibility of genomic profiling across different patient groups. Hence, our hypothesis is that the panels of signature biomarkers will be much more effective to improve the diagnosis and prediction of patient survival outcome with high sensitivity and specificity. Ovarian cancer is heterogeneous in nature and contain a sub-population of stem cell-like characteristics that has the ability to grow as anchorage-independent manner and subsequently is able to metastasize. Highly tumorigenic and chemotherapy-resistant cancer stem cells (CSCs)-specific biomarkers therefore reflects the interesting possibilities to be targeted to minimize the high frequency of relapse and resistance to drugs. Several putative ovarian CSC markers such as CD24, CD44, CD133, SSEA have already been proposed in recent studies, yet, a large panel of updated biomarkers have high clinical relevance to define the prospective isolation of viable circulating CSCs. Therefore, this review highlights current evidence based updated ovarian cancer specific prognostic and diagnostic biomarkers and potential importance of CSCs in context of tumorigenicity and metastatic activity for fundamental biological and clinical implications.  相似文献   
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Algae are a group of ubiquitous photosynthetic organisms comprising eukaryotic green algae and Gram-negative prokaryotic cyanobacteria, which have immense potential as a bioresource for various industries related to biofuels, pharmaceuticals, nutraceuticals and feed. This fascinating group of organisms also has applications in modern agriculture through facilitating increased nutrient availability, maintaining the organic carbon and fertility of soil, and enhancing plant growth and crop yields, as a result of stimulation of soil microbial activity. Several cyanobacteria provide nitrogen fertilization through biological nitrogen fixation and through enzymatic activities related to interconversions and mobilization of different forms of nitrogen. Both green algae and cyanobacteria are involved in the production of metabolites such as growth hormones, polysaccharides, antimicrobial compounds, etc., which play an important role in the colonization of plants and proliferation of microbial and eukaryotic communities in soil. Currently, the development of consortia of cyanobacteria with bacteria or fungi or microalgae or their biofilms has widened their scope of utilization. Development of integrated wastewater treatment and biomass production systems is an emerging technology, which exploits the nutrient sequestering potential of microalgae and its valorisation. This review focuses on prospects and challenges of application of microalgae in various areas of agriculture, including crop production, protection and natural resource management. An overview of the recent advances, novel technologies developed, their commercialization status and future directions are also included.  相似文献   
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Improved Samba Mahsuri (ISM) is a popular, high-yielding, bacterial blight resistant rice variety possessing medium-slender grain type. As ISM is highly susceptible to blast disease of rice, through the present study we have transferred two major blast resistance genes, Pi2 and Pi54 into the elite variety by marker-assisted backcross breeding. The two blast resistance genes were transferred to ISM through sets of backcrosses. In every backcross generation, PCR-based markers, specific for the blast resistance genes (Pi2 and Pi54) and bacterial blight resistance genes (Xa21, xa13 and xa5) were utilized for foreground selection, while a set of 144 parental polymorphic SSR markers were used for background selection and backcrossing was carried out until BC2 generation. A solitary BC2F1 plant possessing Pi2 or Pi54 along with Xa21, xa13 and xa5 and >?90% recovery of ISM genome was selected from the two sets of backcrosses were crossed and the intercross F1s (ICF1s) thus obtained were selfed to generate ICF2s. Homozygous ICF2 plants carrying all the five resistance genes were identified through markers and advanced through selfing till ICF5 generation by adopting pedigree method of selection. Three best lines at ICF5, possessing excellent resistance against bacterial blight and blast and closely resembling or superior to ISM in terms of grain quality: yield and agro-morphological traits have been identified and advanced for multi-location trials.  相似文献   
168.
In ELISA, a popular analytical diagnostic tool, the stable non-covalent immobilization (coating) of hydrophilic proteins/peptides on to hydrophobic polystyrene surface has remained a major common challenge. Recombinant bacterial lipid modification of proteins in Escherichia coli system has been shown in this study to solve this problem owing to the hydrophobic anchorage provided by three fatty acyl groups in N-acyl-S-diacylglyceryl Cys at the N-terminus. Exploiting this first post-translational protein engineering, the most abundantly expressed white spot syndrome viral protein ICP11 was lipid-modified and tested as a new target in a new ELISA method useful to shrimp farming. The lipid served as a potent adjuvant to enhance the titer (16 times) of higher affinity antibodies where amino terminal lipoamino acid N-acyl-S-diacylglyceryl cysteine of bacterial lipoproteins induce inflammatory responses through TLR and stimulate humoral immune responses without additional adjuvant and also aided in the immobilization of even a few nanograms of ICP11. Competition between the immobilized and the free antigen from the sample provided a sensitive measure of antigen in the infected shrimp tissues. The detection limit for ICP11 protein using competitive ELISA was 250 pg and the linear range of the assay was 15–240 ng.  相似文献   
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Summary Root outgrowths formed on the root tissue of geranium (Pelargonium x hortorum Bailey cv. Kim and cv. Shone Helena) plants in response to treatment with the phenylurea derivative, thidiazuron (N-phenyl-N-1,2,3-thiadiazol-5-ylurea; TDZ). Treatment with the cytokinin N6-benzylaminopurine (BAP) or the auxin -naphthaleneacetic acid (NAA) did not result in stimulation of similar abnormal structures on the root tissue. Significantly more outgrowths developed on roots of plants treated with 10 M and 20 M TDZ than on control plants or those treated with 1 M TDZ for the eight-week treatment period. Some outgrowths produced shoots and plantlets while still attached to roots, and regenerants were easily separated from the root tissue and transferred to soil in the greenhouse where they grew to maturity. Histological observations suggested these outgrowths originated from the vascular cambium region of the root.  相似文献   
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