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91.
Tyrosine kinase inhibitors (TKIs) are important in managing lymphoid malignancies by targeting B-cell receptor signaling pathways. Entospletinib (GS-9973) is an oral, selective inhibitor of spleen tyrosine kinase (Syk), currently in the phase II clinical trials for the treatment of chronic lymphocytic leukemia. Syk is abundantly present in the cells of hematopoietic lineage that mediates cell proliferation, differentiation, and adhesion. In this current study, we evaluated the efficacy of GS-9973 to overcome multidrug resistance (MDR) due to the overexpression of the ABCG2 transporter in the non-small cell lung cancer (NSCLC) cell line, NCI-H460/MX20. In vitro, 3 μM of GS-9973 reversed the drug resistance of NCI-H460/MX20 cell line to mitoxantrone or doxorubicin. GS-9973, at 3 μM reverses ABCG2-mediated MDR by blocking ABCG2 efflux activity and downregulating ABCG2 expression at the protein level but did not alter the ABCG2 mRNA expression and subcellular localization of the ABCG2 protein compared to drug-resistant cells incubated with the vehicle. GS-9973 produced a moderate concentration-dependent increase in the ATPase activity of ABCG2 (EC50 = 0.42 µM) and molecular docking data indicated that GS-9973 had a high affinity (-10.226 kcal/mol) for the substrate-binding site of ABCG2. Finally, HPLC analysis proved that the intracellular concentration of GS-9973 is not significantly different in both parental and resistant cell lines. In conclusion, our study suggests that in vitro, GS-9973 in combination with certain anticancer drugs, represent a strategy to overcome ABCG2-mediated MDR cancers.  相似文献   
92.
In view of the enormous challenge and pressure on farmers to feed 9 billion plus people and billions of animals who are going to be living in our planet in 2050, new technologies must be invented, assessed and adapted. Farmer welfare and provision of resources required for their work is of paramount importance. India has benefited from Bt cotton technology and will certainly benefit from other biotech crops that have been carefully developed and assessed for consumption and environmental safety.  相似文献   
93.
We wanted to determine whether methamphetamine use affects a subset of plasma proteins in HIV-infected persons. Plasma samples from two visits were identified for subjects from four groups: HIV+, ongoing, persistent METH use; HIV+, short-term METH abstinent; HIV+, long term METH abstinence; HIV negative, no history of METH use. Among 390 proteins identified, 28 showed significant changes in expression in the HIV+/persistent METH+ group over the two visits, which were not attributable to HIV itself. These proteins were involved in complement, coagulation pathways and oxidative stress. Continuous METH use is an unstable condition, altering levels of a number of plasma proteins.  相似文献   
94.
Summary Site-directed Tn5 mutagenesis by gene replacement method, via homologous recombination, was used to identify symbiotically essential regions in the genome of cowpea Rhizobium spp. IRc78. Transposon insertions with-in the nifK hybridizing region or in the regions spanning 10 kb downstream of the nifK have revealed the presence of functional genes required for nitrogen fixation. Six single Tn5 insertions resulted in nod+ fix phenotypes and one in nod+ but reduced fix+ phenotype. All seven Tn5 insertions were stable before, during and after plant passage. However, IRc78 transconjugants containing duplicated nif copies, (a normal and a Tn5 inserted copy separated by vector sequences) were unstable. In five IRc78::Tn5 strains, the mutant phenotypes were corrected by an extrachromosomally stable vector containing wild type nif alleles. Our experiments suggest that the correction to nod+ fix+ phenotype is by complementation although correction by recombination cannot be completely excluded.  相似文献   
95.
96.
BackgroundTinospora cordifolia (Thunb.) Miers (Giloy) has been applied successfully as an anti-inflammatory, anti-diabetic, and even as an anti-cancer agent. Yet, to date, the application of Giloy has not been explored concerning oral cancer.ObjectivesTo assess the effect of T cordifolia (Thunb.) Miers (Giloy) extract (TcE) on an oral cancer cell line.MethodsAW13516 (oral cancer cell line) cells were treated with the prepared aqueous extract of TcE for 24 h at various concentrations ranging between 5 μg/ml and 100 μg/ml and compared with control (cells without treatment). Thee effect of the extracts on apoptosis was assessed by through Annexin V flow cytometry assay and Luminometry based assessment of Caspase 8, 9 and caspase 3/7 activity. RNA was isolated from treated cells and gene expression of selected metastatic genes (MMP1, MMP10, and CXCL8); epithelial-mesenchymal stem cell genes (TWIST1, SNAIL, ZEB1, Oct4) and stemness related genses (Nanog, Sox2) were analyzed by using a quantitative real-time PCR system. The experiments were performed in triplicates.ResultsAqueous extract of TcE was found to induce apoptosis inducer in AW13516 cells in a concentration-dependent manner and was potent even at a low concentration of 5 μg/ml. The apoptosis induction was confirmed with the caspase activity assay. Treatment of the cells with the extract for 24 h exhibited a significant decrease in the expression of EMT genes in a dose-dependent manner without an effect on the metastatic genes.ConclusionAqueous extract of TcE induces apoptosis-mediated cell death in the oral cancer cell line AW13516 while attenuating its potential for epithelial mesenchymal transition.  相似文献   
97.
利用同源克隆的方法得到水稻的泛素连接酶APC/C辅助激活子CDH1的同源基因 OsCCS52B.通过蛋白质序列分析发现OsCCS52B 和苜蓿及拟南芥中的AtCCS52B(细胞周期转换开关基因)基因同源性最高;RNA原位杂交实验研究发现,OsCCS52B基因在减数分裂期间的表达存在一个高-低-高的波动变化.由于OsCCS52B表达变动的这个模式和减数分裂M-M(细胞分裂-细胞分裂)的转化过程中对受CDH1调控的细胞周期激酶CDKA活性的要求相一致,所以推测水稻的OsCCS52B基因参与了水稻减数分裂M-M转换期间对染色体复制的调控.同时,RNA原位杂交实验显示,OsCCS52B在核内复制旺盛的组织如根尖分生组织和穗下节的分生区和伸长区表达强烈,证明OsCCS52B可能参与了水稻的核内复制.  相似文献   
98.
Rice (Oryza sativa L.) and maize (Zey mays) are grown in 3.5 million hectares (Mha) in Asia that includes 1.5 Mha in South Asia. These crops are grown in sequence on the same land in the same year either in double–or triple-crop systems to meet the rice demand of a rapidly expanding human population and maize demand of livestock and poultry. The objective of this review is to provide a comprehensive overview of the current state of technical knowledge on agro-ecosystems and adaptation, area and distribution, yield potential and yield gaps, and nutrient management for rice-maize (R-M) systems in South Asia. Rice-maize systems are emerging all around South Asia but in particular are developing quite rapidly in Bangladesh and South and North India. Yield potential of rice and maize, as estimated by ORYZA2000 and Hybrid Maize models, reaches up to 15 and 22 t ha-1, respectively. However, data from several environments in India reveal gaps between potential and attainable yields of maize of upto 100% and between attainable and actual yields of upto 25–50%. Nutrient demand of R-M system is high due to high nutrient removal by high-yielding maize. Nutrient balance studies for these highly–productive and nutrient-extractive systems are scarce in South Asia. The review outlines principles of nutrient management for R-M systems, and identifies development, refinement, and dissemination of the integrated plant nutrition system technologies based on site-specific nutrient management principles as priorities for future research to increase yield, profitability, and sustainability of R-M systems.  相似文献   
99.
We present a new method to efficiently estimate very large numbers of p-values using empirically constructed null distributions of a test statistic. The need to evaluate a very large number of p-values is increasingly common with modern genomic data, and when interaction effects are of interest, the number of tests can easily run into billions. When the asymptotic distribution is not easily available, permutations are typically used to obtain p-values but these can be computationally infeasible in large problems. Our method constructs a prediction model to obtain a first approximation to the p-values and uses Bayesian methods to choose a fraction of these to be refined by permutations. We apply and evaluate our method on the study of association between 2-way interactions of genetic markers and colorectal cancer using the data from the first phase of a large, genome-wide case-control study. The results show enormous computational savings as compared to evaluating a full set of permutations, with little decrease in accuracy.  相似文献   
100.
The radioprotective effect of the hydroalcoholic extract of ginger rhizome, Zingiber officinale (ZOE), was studied. Mice were given 10 mg/kg ZOE intraperitoneally once daily for five consecutive days before exposure to 6-12 Gy of gamma radiation and were monitored daily up to 30 days postirradiation for the development of symptoms of radiation sickness and mortality. Pretreatment of mice with ZOE reduced the severity of radiation sickness and the mortality at all doses. The ZOE treatment protected mice from GI syndrome as well as bone marrow syndrome. The dose reduction factor for ZOE was found to be 1.15. The optimum protective dose of 10 mg/kg ZOE was 1/50 of the LD50 (500 mg/kg). Irradiation of the animals resulted in a dose-dependent elevation in the lipid peroxidation and depletion of GSH on day 31 postirradiation; both effects were lessened by pretreatment with ZOE. ZOE also had a dose-dependent antimicrobial activity against Pseudomonas aeruginosa, Salmonella typhimurium, Escherichia coli and Candida albicans.  相似文献   
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