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91.
92.
DNA damage is a relatively common event in eukaryotic cell and may lead to genetic mutation and even cancer. DNA damage induces cellular responses that enable the cell either to repair the damaged DNA or cope with the damage in an appropriate way. Histone proteins are also the fundamental building blocks of eukaryotic chromatin besides DNA, and many types of post-translational modifications often occur on tails of histones. Although the function of these modifications has remained elusive, there is ever-growing studies suggest that histone modifications play vital roles in several chromatin-based processes, such as DNA damage response. In this review, we will discuss the main histone modifications, and their functions in DNA damage response. 相似文献
93.
Qiang Li Bo Chen Peng Lin Jiali Zhou Juhong Zhan Qiuying Shen 《International journal of phytoremediation》2016,18(2):103-109
The root powder of long-root Eichhornia crassipes, as a new kind of biodegradable adsorbent, has been tested for aqueous adsorption of Pb, Zn, Cu, and Cd. From FT-IR, we found that the absorption peaks of phosphorous compounds, carbonyl, and nitrogenous compounds displayed obvious changes before and after adsorption which illustrated that plant characteristics may play a role in binding with metals. Surface properties and morphology of the root powders have been characterized by means of SEM and BET. Energy spectrum analysis showed that the metals were adsorbed on root powders after adsorption. Then, optimum quantity of powder, pH values, and metal ion concentrations in single-system and multi-system were detected to discuss the characteristics and mechanisms of metal adsorption. Freundlich model and the second-order kinetics equation could well describe the adsorption of heavy metals in single-metal system. The adsorption of Pb, Zn, and Cd in the multi-metal system decreased with the concentration increased. At last, competitive adsorption of every two metals on root powder proved that Cu and Pb had suppressed the adsorption performance of Cd and Zn. 相似文献
94.
Genetic and epigenetic heterogeneity of epithelial ovarian cancer and the clinical implications for molecular targeted therapy 下载免费PDF全文
Jiaxin Yang Menghui Li Zhenyu Zhang Keng Shen 《Journal of cellular and molecular medicine》2016,20(4):581-593
Epithelial ovarian cancer (EOC) is the most lethal gynaecological malignancy, and tumoural heterogeneity (TH) has been blamed for treatment failure. The genomic and epigenomic atlas of EOC varies significantly with tumour histotype, grade, stage, sensitivity to chemotherapy and prognosis. Rapidly accumulating knowledge about the genetic and epigenetic events that control TH in EOC has facilitated the development of molecular‐targeted therapy. Poly (ADP‐ribose) polymerase (PARP) inhibitors, designed to target homologous recombination, are poised to change how breast cancer susceptibility gene (BRCA)‐related ovarian cancer is treated. Epigenetic treatment regimens being tested in clinical or preclinical studies could provide promising novel treatment approaches and hope for improving patient survival. 相似文献
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96.
<正>Traditional molecular biology, defined in a broad sense to include most of life science research that focuses on single or a few genes to understand their functions and application values to medicine and agriculture, has generated interesting and important accomplishments. Meanwhile, in recent years,a new paradigm is emerging in biological research that further adds new approaches and new dimension of scientific 相似文献
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98.
Effects of wildfire on soil respiration and its heterotrophic and autotrophic components in a montane coniferous forest 总被引:1,自引:0,他引:1
Jian Song Zhen Liu Yuan Zhang Tao Yan Zehao Shen Shilong Piao 《Journal of Plant Ecology》2019,12(2):336
Aims
Episodic wildfires are expected to occur more frequently under future climate change scenarios, with substantial effects on CO2exchange between terrestrial ecosystems and the atmosphere. This study examined the effects of wildfire on soil respiration (RS) and its heterotrophic (RH) and autotrophic (RA) components, as well as their temperature responses (temperature sensitivity,Q10). 相似文献
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100.
Pharmaceuticals and personal care products (PPCPs) exist and are often grouped into categories according to their functional mechanism and effect on human health. In this study, six types of PPCPs were detected and characterized in the drinking water of Shanghai, covering 35 water treatment plants. The PPCPs concentrations were ranged from 2.57 ng/L to 19.4 ng/L and over 10 ng/L in nearly half of the samples. Hormones, blockers, and veterinary drugs were considered to contribute negligibly to the overall pollution from PPCPs for their low concentrations. However, dicyclohexylamine and psycholeptics were detected in all samples, with a maximum concentration of 11.8 ng/L, 7.82 ng/L, and 9.07 ng/L for dicyclohexylamine, sertraline, and sulpiride, respectively. In addition, high toxicity antitumor drug cyclophosphamide was detected in one-third of the samples and the highest concentration was 3.72 ng/L.
In all, the four PPCPs evaluated accounted for over 80% of the detected PPCPs levels. Therefore, it was determined that the major PPCPs are contributing to water pollution in the region. While these compounds do not pose a potential human health risk at their present levels, close attention should be paid to the use of these PPCPs and their discharge into drinking water source. 相似文献