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91.
In a combined approach of phenotypic and genotypic characterization, 28 indigenous rhizobial isolates obtained from different chickpea growing regions in peninsular and northern India were analyzed for diversity. The field isolates were compared to two reference strains TAL620 and UPM-Ca142 representing M. ciceri and M. mediterraneum respectively. Phenotypic markers such as resistance to antibiotics, tolerance to salinity, temperature, pH, phosphate solubilization ability, growth rate and also symbiotic efficiency showed considerable diversity among rhizobial isolates. Their phenotypic patterns showed adaptations of rhizobial isolates to abiotic stresses such as heat and salinity. Two salt tolerant strains (1.5% NaCl by T1 and T4) with relatively high symbiotic efficiency and two P-solubilising strains (66.7 and 71 microg/ml by T2 and T5) were identified as potential bioinoculants. Molecular profiling by 16S ribosomal DNA Restriction Fragment Length Polymorphism (RFLP) revealed three clusters at 67% similarity level. Further, the isolates were differentiated at intraspecific level by 16S rRNA gene phylogeny. Results assigned all the chickpea rhizobial field isolates to belong to three different species of Mesorhizobium genus. 46% of the isolates grouped with Mesorhizobium loti and the rest were identified as M. ciceri and M. mediterraneum, the two species which have been formerly described as specific chickpea symbionts. This is the first report on characterization of chickpea nodulating rhizobia covering soils of both northern and peninsular India. The collection of isolates, diverse in terms of species and symbiotic effectiveness holds a vast pool of genetic material which can be effectively used to yield superior inoculant strains. 相似文献
92.
Nagendra K. Singh Deepak K. Gupta Pawan K. Jayaswal Ajay K. Mahato Sutapa Dutta Sangeeta Singh Shefali Bhutani Vivek Dogra Bikram P. Singh Giriraj Kumawat Jitendra K. Pal Awadhesh Pandit Archana Singh Hukum Rawal Akhilesh Kumar G. Rama Prashat Ambika Khare Rekha Yadav Ranjit S. Raje Mahendra N. Singh Subhojit Datta Bashasab Fakrudin Keshav B. Wanjari Rekha Kansal Prasanta K. Dash Pradeep K. Jain Ramcharan Bhattacharya Kishor Gaikwad Trilochan Mohapatra R. Srinivasan Tilak R. Sharma 《Journal of plant biochemistry and biotechnology.》2012,21(1):98-112
Pigeonpea (Cajanus cajan) is an important grain legume of the Indian subcontinent, South-East Asia and East Africa. More than eighty five percent of the world pigeonpea is produced and consumed in India where it is a key crop for food and nutritional security of the people. Here we present the first draft of the genome sequence of a popular pigeonpea variety ??Asha??. The genome was assembled using long sequence reads of 454 GS-FLX sequencing chemistry with mean read lengths of >550?bp and >10-fold genome coverage, resulting in 510,809,477?bp of high quality sequence. Total 47,004 protein coding genes and 12,511 transposable elements related genes were predicted. We identified 1,213 disease resistance/defense response genes and 152 abiotic stress tolerance genes in the pigeonpea genome that make it a hardy crop. In comparison to soybean, pigeonpea has relatively fewer number of genes for lipid biosynthesis and larger number of genes for cellulose synthesis. The sequence contigs were arranged in to 59,681 scaffolds, which were anchored to eleven chromosomes of pigeonpea with 347 genic-SNP markers of an intra-species reference genetic map. Eleven pigeonpea chromosomes showed low but significant synteny with the twenty chromosomes of soybean. The genome sequence was used to identify large number of hypervariable ??Arhar?? simple sequence repeat (HASSR) markers, 437 of which were experimentally validated for PCR amplification and high rate of polymorphism among pigeonpea varieties. These markers will be useful for fingerprinting and diversity analysis of pigeonpea germplasm and molecular breeding applications. This is the first plant genome sequence completed entirely through a network of Indian institutions led by the Indian Council of Agricultural Research and provides a valuable resource for the pigeonpea variety improvement. 相似文献
93.
Under the network environment, the trading volume and asset price of a financial commodity or instrument are affected by various complicated factors. Machine learning and sentiment analysis provide powerful tools to collect a great deal of data from the website and retrieve useful information for effectively forecasting financial risk of associated companies. This article studies trading volume and asset price risk when sentimental financial information data are available using both sentiment analysis and popular machine learning approaches: artificial neural network (ANN) and support vector machine (SVM). Nonlinear GARCH-based mining models are developed by integrating GARCH (generalized autoregressive conditional heteroskedasticity) theory and ANN and SVM. Empirical studies in the U.S. stock market show that the proposed approach achieves favorable forecast performances. GARCH-based SVM outperforms GARCH-based ANN for volatility forecast, whereas GARCH-based ANN achieves a better forecast result for the volatility trend. Results also indicate a strong correlation between information sentiment and both trading volume and asset price volatility. 相似文献
94.
Swagatika Dash Cuili Jin On On Lee Ying Xu Pei-Yuan Qian 《Journal of industrial microbiology & biotechnology》2009,36(8):1047-1056
In this study, we screened seven novel sponge-associated marine bacteria for their antibacterial and antilarval-settlement
activity in order to find possible new sources of non-toxic or less toxic bioactive antifoulants. The anti-bacterial-growth
activity of crude extracts of each bacterium was evaluated by the disk-diffusion assay. Extracts of four potent bacteria with
high and broad spectra of antibacterial activity were further separated with solvents of different polarities (hexane and
ethyl acetate). To evaluate their indirect inhibitive effect on larval settlement, we tested for their antibiofilm formation
activity against two of the test bacteria (Vibrio halioticoli and Loktanella hongkongensis) inductive to Hydroides elegans larval settlement. About 60 and 87% of the extracts inhibited biofilm formation by V. halioticoli and by L. hongkongensis respectively. The extracts were also tested for their direct antilarval-settlement activity against the barnacle Balanus amphitrite and the polychaete H. elegans; 87% of the extracts had a strong inhibitive effect on larval settlement of both species. Extracts of two of the isolates
completely inhibited larval settlement of B. amphitrite at 70 μg ml−1 and H. elegans at 60 μg ml−1. The organic extracts of Winogradskyella poriferorum effectively inhibited the larval settlement of both H. elegans and B. amphitrite and the biofilm formation of the two bacterial species. The metabolites present in the active crude extracts were profiled
using GC MS, and the most prevalent metabolites present in all extracts were identified. This study successfully identified
potential new sources of antifouling compounds.
相似文献
Pei-Yuan QianEmail: |
95.
Maitra A Shanker J Dash D Sannappa PR John S Siwach P Rao VS Sridhara H Kakkar VV 《Journal of genetics》2010,89(4):437-447
We investigated the promoter polymorphisms of the pituitary growth hormone gene (GH1) and exon 3 deletion polymorphism (GHRd3) in its receptor gene (GHR) in 299 angiographically proven patients with coronary artery disease (CAD) and 231 asymptomatic controls enrolled in the
ongoing Indian Atherosclerosis Research Study. Real time PCR based analysis of the GHR variant showed significant association of the GHRd3 deletion allele with CAD (OR 0.48, 95% CI: 0.30–0.76, P = 0.0014) and a dominant model of inheritance (Akaike information criterion = 482). The deletion allele showed significant
association with high plasma HDL-c levels (P = 0.001). Sequencing of the proximal promoter region of GH1 revealed 12 novel polymorphisms and a TAGA haplotype constituted by the functional SNPs rs2005171, rs11568828, rs2005172 and rs6171, that showed significant association
with CAD alone (adjusted OR of 3.31 (95% CI = 1.33–8.29, P = 0.011) and in CAD patients with diabetes (P = 0.019). Mean standardized height was associated with three of the four haplotype-tagging SNPs in the cohort (P ≤ 0.03). Eleven of the 12 polymorphic promoter SNPs contributed to 14.7% of variation in height in females in the whole dataset
(P = 0.029). CAD patients with history of stroke exhibited marginally significantly lower mean height as compared to rest of
the cohort (P < 0.006). In conclusion, genetic polymorphisms in the GHR gene and its ligand, GH1, may modulate the risk of CAD in the Asian Indian population. 相似文献
96.
Natural disasters by definition are surprises, causing a great deal of damage and inconvenience. Earthquakes are among the most terrifying and destructive natural disasters threatening humans. Emergency management has been described as the process of coordinating an emergency or its aftermath through communication and organization for deployment and the use of emergency resources. This special section of HERA provides the state of the art studies of risk and emergency management related to the Wenchuan earthquake that occurred in China in May 2008. 相似文献
97.
Bret Poat Sidhartha Hazari Partha K. Chandra Feyza Gunduz Luis A. Balart Xavier Alvarez Srikanta Dash 《PloS one》2010,5(9)
Background
We have developed multiple stable cell lines containing subgenomic HCV RNA that are resistant to treatment with interferon alpha (IFN-α. Characterization of these IFN-α resistant replicon cells showed defects in the phosphorylation and nuclear translocation of STAT1 and STAT2 proteins due to a defective Jak-STAT pathway.Methodology/Principal Findings
In this study, we have developed an alternative strategy to overcome interferon resistance in a cell culture model by improving intracellular STAT1 signaling. An engineered STAT1-CC molecule with double cysteine substitutions in the Src-homology 2 (SH2) domains of STAT1 (at Ala-656 and Asn-658) efficiently phosphorylates and translocates to the nucleus of IFN-resistant cells in an IFN-γ dependent manner. Transfection of a plasmid clone containing STAT1-CC significantly activated the GAS promoter compared to wild type STAT1 and STAT3. The activity of the engineered STAT1-CC is dependent upon the phosphorylation of tyrosine residue 701, since the construct with a substituted phenylalanine residue at position 701 (STAT1-CC-Y701F) failed to activate GAS promoter in the replicon cells. Intracellular expression of STAT1-CC protein showed phosphorylation and nuclear translocation in the resistant cell line after IFN-γ treatment. Transient transfection of STAT1-CC plasmid clone into an interferon resistant cell line resulted in inhibition of viral replication and viral clearance in an IFN-γ dependent manner. Furthermore, the resistant replicon cells transfected with STAT1-CC constructs significantly up regulated surface HLA-1 expression when compared to the wild type and Y to F mutant controls.Conclusions
These results suggest that modification of the SH2 domain of the STAT1 molecule allows for improved IFN-γ signaling through increased STAT1 phosphorylation, nuclear translocation, HLA-1 surface expression, and prolonged interferon antiviral gene activation. 相似文献98.
Carmel M. McVicar Liza M. Colhoun Jodie L. Abrahams Claire L. Kitson Ross Hamilton Reinhold J. Medina Dash Durga Tom A. Gardiner Pauline M. Rudd Alan W. Stitt 《PloS one》2010,5(7)
Background
Erythropoiesis stimulating agents (ESAs) are widely used to treat anaemia but concerns exist about their potential to promote pathological angiogenesis in some clinical scenarios. In the current study we have assessed the angiogenic potential of three ESAs; epoetin delta, darbepoetin alfa and epoetin beta using in vitro and in vivo models.Methodology/Principal Findings
The epoetins induced angiogenesis in human microvascular endothelial cells at high doses, although darbepoetin alfa was pro-angiogenic at low-doses (1–20 IU/ml). ESA-induced angiogenesis was VEGF-mediated. In a mouse model of ischaemia-induced retinopathy, all ESAs induced generation of reticulocytes but only epoetin beta exacerbated pathological (pre-retinal) neovascularisation in comparison to controls (p<0.05). Only epoetin delta induced a significant revascularisation response which enhanced normality of the vasculature (p<0.05). This was associated with mobilisation of haematopoietic stem cells and their localisation to the retinal vasculature. Darbepoetin alfa also increased the number of active microglia in the ischaemic retina relative to other ESAs (p<0.05). Darbepoetin alfa induced retinal TNFα and VEGF mRNA expression which were up to 4 fold higher than with epoetin delta (p<0.001).Conclusions
This study has implications for treatment of patients as there are clear differences in the angiogenic potential of the different ESAs. 相似文献99.
MUC1 gene encodes a transmembrane mucin glycoprotein that is overexpressed in human breast cancer and colon cancer. The objective
of this study was to develop an in situ gel delivery system containing paclitaxel (PTX) and mucoadhesives for sustained and
targeted delivery of anticancer drugs. The delivery system consisted of chitosan and glyceryl monooleate (GMO) in 0.33M citric
acid containing PTX. The in vitro release of PTX from the gel was performed in presence and absence of Tween 80 at drug loads
of 0.18%, 0.30%, and 0.54% (wt/wt), in Sorensen’s phosphate buffer (pH 7.4) at 37°C. Different mucin-producing cell lines
(Calu-3>Caco-2) were selected for PTX transport studies. Transport of PTX from solution and gel delivery system was performed
in side by side diffusion chambers from apical to basal (A-B) and basal to apical (B-A) directions. In vitro release studies
revealed that within 4 hours, only 7.61%±0.19%, 12.0%±0.98%, 31.7%±0.40% of PTX were released from 0.18%, 0.30%, and 0.54%
drugloaded gel formulation, respectively, in absence of Tween 80. However, in presence of surfactant (0.05% wt/vol) in the
dissolution medium, percentages of PTX released were 28.1%±4.35%, 44.2%±6.35%, and 97.1%±1.22%, respectively. Paclitaxel has
shown a polarized transport in all the cell monolayers with B-A transport 2 to 4 times higher than in the A-B direction. The
highest mucin-producing cell line (Calu-3) has shown the lowest percentage of PTX transport from gels as compared with Caco-2
cells. Transport of PTX from mucoadhesive gels was shown to be influenced by the mucin-producing capability of cell. 相似文献
100.
Dash S 《Human biology; an international record of research》2004,76(5):779-783
The native population of Bahrain has a high prevalence of hemoglobinopathies and G6PD deficiency, probably as a result of past malarial endemism. We used the Biorad-Variant hemoglobin testing system for primary screening of hemoglobinopathies in 20,000 individuals. Hemoglobin abnormalities were detected in 7,206 (36.3%) cases. 相似文献