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81.
In this letter, a variety of simple 6-chloro-4-(4-substituted piperazinyl)quinazoline derivatives was prepared. Preliminary bioassays revealed that these compounds showed good antibacterial activities toward phytopathogens Ralstonia solanacearum and Xanthomonas oryzae pv. oryzae (Xoo). Among these derivatives, compounds 5a, 5d, 5e, 5f, 5p, 5q, 6b, and 6d exhibited potent inhibition effects against R. solanacearum with EC50 within 4.60–9.94 µg/mL, especially, compound 5g exerted the strongest activity with EC50 of 2.72 µg/mL; compound 6b possessed the best inhibitory activity toward Xoo with EC50 of 8.46 µg/mL. Subsequently, a good predictive three-dimensional quantitative structure–activity relationship (3D-QSAR) model was constructed via CoMFA to direct the future structural modification and optimization. Furthermore, the pathogens’ topological studies were performed to explore the possible antibacterial mechanism. Given their simple frameworks and facile synthesis, title compounds can serve as the potential antibacterial leads.  相似文献   
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Pancreatic cancer (PC) is the fourth most frequent cause of cancer death in the United States. Emerging evidence suggests that pancreatic cancer stem cells (CSCs) play a crucial role in the development and progression of PC. Recently, there is increasing evidence showing that chemopreventive agents commonly known as nutraceuticals could target and eliminate CSCs that have been proposed as the root of the tumor progression, which could be partly due to attenuating cell signaling pathways involved in CSCs. Therefore, targeting pancreatic CSCs by nutraceuticals for the prevention of tumor progression and treatment of PC may lead to the development of novel strategy for achieving better treatment outcome of PC patients. In this review article, we will summarize the most recent advances in the pancreatic CSC field, with particular emphasis on nutraceuticals that target CSCs, for fighting this deadly disease.  相似文献   
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A series of 6,7,8-trimethoxy N-aryl-substituted-4-aminoquinazoline derivatives were synthesized as epidermal growth factor receptor (EGFR) inhibitors, and their antitumor activities were assessed in the gastric cancer cell line SGC7901 using MTT assay. All compounds of Tg114 were found to inhibit SGC7901 cell proliferation, and compound Tg11 (IC50?=?0.434?μM) was found to be slightly more effective against SGC7901 cells than epirubicin (IC50?=?5.16?μM). This suggests that compound Tg11 can be used as a new substitution structure to develop more efficacious antitumor agents. Western blot analysis showed that treatment with Tg11 (40?μM for 30?min) resulted in near complete inhibition of EGF-induced ERK1/2 phosphorylation, indicating that its anti-proliferative effect is largely associated with inhibition of ERK1/2 activation. These data imply that Tg11 is a potential anticancer agent capable of inhibiting cell proliferation.  相似文献   
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p27和p53基因在大肠癌中的表达及临床意义   总被引:1,自引:0,他引:1  
目的 研究大肠癌患者癌组织中p27、p53基因的表达及其相互之间的关系,以探讨p27、p53基因在大肠癌发生中的作用及临床意义。方法 运用原位杂交方法及免疫组化SP法检测58例大肠癌组织及正常黏膜中p27mRNA和P27蛋白的表达,同时运用免疫组化法分析相同组织中P53蛋白表达状况。结果 p27mRNA在大肠癌组织及正常黏膜中的表达阳性率均为100%。P27蛋白在大肠癌组织中的表达阳性率为55.17%,在正常黏膜中的表达阳性率为96.55%(P〈0.01);癌组织中P53蛋白表达阳性率为53.45%,正常黏膜未见P53蛋白表达(P〈0.01);大肠癌组织中P27与P53蛋白表达无明显相关性。P27蛋白的表达与肿瘤分化程度呈负相关(P〈0.01),与临床其它病理因素均无相关性(P〉0.05)。大肠癌组织中P53蛋白表达与临床病理因素亦无相关性(P〉0.05)。结论 P27蛋白表达的调控主要在转录后水平,P27蛋白检测可作为评价大肠癌恶性程度和预后判断的重要指标。P27及P53蛋白在大肠癌的发生发展过程中具有重要作用。  相似文献   
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Human growth hormone (hGH) is the major and important hormone component of human being. At present, hGH for clinical uses is mostly produced in Escherichia coli, which requires costly denaturation and refolding to recover functionality. To obtain long-term bioactive hormone, we used hGH as a foreign gene and constructed a recombinant plasmid pJS700-hGH which carries a recombinant gene cotC-hgh with an enterokinase site under the control of cotC promoter. Plasmid pJS700-hGH was transformed into Bacillus subtilis by double crossover and an amylase-inactivated mutant was produced. After spore formation, Western blot and fluorescence immunoassay were used to monitor hGH surface expression on spores. Oral administration to silkworm with spores displaying hGH further showed that the recombinant spores may have potential ability to be digested and absorbed into the silkworm’s hemolymph due to both the resistant characters of spores and the addition of enterokinase site.  相似文献   
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This article aims to estimate the efficiency of 26 different European Countries over 2001 and 2012 comparing their performance. Data Envelopment Analysis technique is used in a first step to evaluate the performance of each European country. The output-oriented model was used with two specifications (Variable and Constant Returns to Scale) including as inputs labour and capital productivity, the weight of fossil energy and the share of renewable energy in GDP (gross domestic product), being the output GDP per GHG (greenhouse gases) emissions. In a second step, the quantile regression technique was used, to explain different efficiency scores through variables as Environmental Taxes Revenues, Resources Productivity and Domestic Material Consumption. Results indicate that share of renewables and non-renewable energy sources are important to explain differences in emissions. They suggest a significant change in the trend of economic and environmental efficiency in European countries and put forward the high disparities existing among them. Policy recommendations point for the need of higher steps if the goal is to equal countries efficiency scores. Moreover, environmental tax revenue effects are negatively stronger in less efficient countries, whereas also exerting negative influence over those more eco-efficient. Transport taxes affect negatively more eco-efficient countries and positively less eco-efficient countries. Energy taxes only seem to positively influence the lower eco-efficient countries. There is also evidence for a negative premium of efficiency considering domestic materials consumption. Finally, resources productivity shows a positive and significant influence independently of the country technical eco-efficiency level.  相似文献   
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This article emphasizes the need for broader approaches for formulating policies for mitigating the effects of climate change especially in the contexts of agricultural decisions, and population health and migration. Constraints imposed by rapid population growth in developing countries for achievement of Sustainable Development Goals are discussed and evidence is presented on “unwanted” fertility from India. Second, comparisons are made for India during 2002–2016 for average well depths in 495 districts and terrestrial water storage anomalies assessed via GRACE satellites for 274 1° × 1° grids using estimated parameters from dynamic random effects models. Lastly, migration patterns especially of the highly educated from 39 sending countries to OECD countries during 2000–2010 are analyzed using dynamic random effects models and total fertility rates were significantly associated with higher migration rates for the highly educated. Implications of the empirical evidence for enhancing global sustainability are discussed.  相似文献   
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