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51.
52.
Background and Purpose
Growing evidence has emerged and controversial results reported on possible relationship between aspirin use and lung cancer risk. We, therefore, conducted this updated and comprehensive meta-analysis to evaluate this issue, with focus on dose-risk and duration-risk relationships.Methods
We searched electronic databases including PUBMED, EMBASE and Cochrane library to identify eligible studies. Relative risk (RR) and its 95% confidence interval (CI) were used for cohort studies, while odds ratio (OR) were employed for case-control studies. The random effects and fixed effects models were used for analyses.Results
18 studies were identified including 19835 lung cancer cases, which were eligible for inclusion in the present meta-analysis. Pooled data from case-control studies showed a significant inverse association between regular aspirin use and lung cancer risk. But for cohort studies, insignificant association was detected with little evidence of heterogeneity (RR: 1.05, 95%CI: 0.95 – 1.16; I2: 10.3%, p value: 0.351). In case-control studies, standard aspirin use (>325mg) was related to lower lung cancer incidence, compared with low-dose aspirin use (75–100mg). A similar trend was observed in cohort studies. Besides, when analysis was restricted to long time regular aspirin use (>5 years), insignificant results were reported in both cohort and case-control studies. Finally, regular aspirin use might result in higher reduction of non-small cell lung cancer incidence among men.Conclusions
Our findings do not support the protective effect of regular aspirin use on lung cancer risk. Long time aspirin use, sex, dose and type of lung cancer might alter the effect of aspirin use on lung cancer risk. More well-designed studies are needed to further clarify these associations. 相似文献53.
【目的】水产养殖过程中蜡状芽孢杆菌(Bacillus cereus)作为益生菌被广泛应用。本研究旨在深入了解分离于养殖水体中的一株蜡状芽孢杆菌S458-1对养殖水体以及养殖对象的影响,以期为菌株S458-1在水产养殖生产上的应用提供理论依据。【方法】根据控制变量法,各试验组鲫鱼养殖模式设置相同温度、盐度、溶氧和pH,利用分光光度法测定水体的水化学指标;利用试剂盒法测定鲫鱼的血清生理生化指标。【结果】添加菌株S458-1处理组(终浓度分别为10~6、10~7、10~8CFU/mL)与对照组(未加S458-1菌)相比:水体活性磷浓度显著性增加(P0.05);同时具有把NH_4~+-N和NO_2~–-N转化为NO_3~–-N的趋势,但无显著性差异(P0.05);养殖鲫鱼血清检测结果显示谷草转氨酶(GOT)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)以及丙二醛(MDA)含量均显著降低(P0.05)。【结论】蜡状芽孢杆菌S458-1具有脱氮解磷、调节水质的作用,并可增强养殖对象的生理健康状态,可作为益生菌应用于水产养殖中,具有较高的应用价值。 相似文献
54.
Li Tao Tang Xiaolu Wu Changcheng Yao Xinmin Wang Yirong Lu Xuemei Lu Jian 《中国科学:生命科学英文版》2020,63(10):1608-1611
正Dear Editor,The coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 coronavirus has become a global pandemic.The SARS-CoV-2 genome has a similarity of 96.2%to that of RaTG13, a bat SARS-CoV-2-related coronavirus detected in Rhinolophus affinis (Paraskevis et al., 2020; Zhou et al.,2020). The SARS-CoV-2 genome also has 85.5%-92.4% 相似文献
55.
Algal bloom phenomenon was defined as “the rapid growth of one or more phytoplankton species which leads to a rapid increase in the biomass of phytoplankton”, yet most estimates of temporal coherence are based on yearly or monthly sampling frequencies and little is known of how synchrony varies among phytoplankton or of the causes of temporal coherence during spring algal bloom. In this study, data of chlorophyll a and related environmental parameters were weekly gathered at 15 sampling sites in Xiangxi Bay of Three‐Gorges Reservoir (TGR, China) to evaluate patterns of temporal coherence for phytoplankton during spring bloom and test if spatial heterogeneity of nutrient and inorganic suspended particles within a single ecosystem influences synchrony of spring phytoplankton dynamics. There is a clear spatial and temporal variation in chlorophyll a across Xiangxi Bay. The degree of temporal coherence for chlorophyll a between pairs of sites located in Xiangxi Bay ranged from –0.367 to 0.952 with mean and median values of 0.349 and 0.321, respectively. Low levels of temporal coherence were often detected among the three stretches of the bay (Down reach, middle reach and upper reach), while high levels of temporal coherence were often found within the same reach of the bay. The relative difference of DIN between pair sites was the strong predictor of temporal coherence for chlorophyll a in down and middle reach of the bay, while the relative difference in Anorganic Suspended Solids was the important factor regulating temporal coherence in middle and upper reach. Contrary to many studies, these results illustrate that, in a small geographic area (a single reservoir bay of approximately 25 km), spatial heterogeneity influence synchrony of phytoplankton dynamics during spring bloom and local processes may override the effects of regional processes or dispersal. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
56.
57.
Zechang Xin Duguang Li Feiyu Mao Yan Du Xiaodong Wang Peng Xu Zhennan Li Jianjun Qian Jie Yao 《Journal of cellular physiology》2020,235(11):8416-8423
Plastin-3 plays a key role in cancer cell proliferation and invasion, but its prognostic value in pancreatic cancer (PACA) remains poorly defined. In this study, we show that PLS3 messenger RNA is overexpressed in PACA tissue compared with normal tissue. We accumulated 207 cases of PACA specimens to perform immunohistochemical analysis and demonstrated that PLS3 levels correlate with T-classification (p < .001) and pathology (p < .001). Furthermore, overall survival rates (p < .001) in tumors with high PLS3 expression were poor, as assessed through Kaplan–Meier survival analysis. PLS3 was found to be an independent prognostic factor for PACA through multivariate Cox regression analysis. Moreover, we found that PLS3 enhances the proliferation and invasion of tumor cells as assessed through Cell Counting Kit-8, wounding healing assays, and Transwell assays. The upregulation of PLS3 also led to enhanced phosphatidylinositol-3 kinase/protein kinase B signaling in PACA cells. These data suggest that PLS3 is a biomarker to estimate PACA progression and represents a molecular target for PACA therapy. 相似文献
58.
菌紫质光生物分子器件及其超快过程 总被引:2,自引:0,他引:2
菌紫质是嗜盐菌紫膜中的一种光能转换蛋白.它具有光致色变和光驱动质子泵功能,其原初光异构化过程极其迅速,可在430fs内完成.由于菌紫质具有一系列独特的光电和光学特性,如对光强的微分响应,高的空间分辨率,高的光灵敏度,高循环次数等,使得它在光电探测,仿视觉系统,人工神经网络,非线性光学及光学信息记录和处理方面有很多重要应用.利用超短脉冲激光技术,高时间分辨光谱学技术及高速取样探测技术,对菌紫质的光循环,原初光异构化,激发态动力学,质子泵机制等方面的研究已取得了许多有意义的结果. 相似文献
59.
Clubroot, caused by Plasmodiophora brassicae, is a severe soil-borne disease that restricts the production of cruciferous crops worldwide. A better understanding of biotic and abiotic factors regulating germination of P. brassicae resting spores in the soil is significant for developing novel control methods. Previous studies reported that root exudates can trigger P. brassicae resting spore germination, thus enabling a targeted attack of P. brassicae on host plant roots. However, we found that native root exudates collected under sterile conditions from host or non-host plants cannot stimulate the germination of sterile spores, indicating that root exudates may not be direct stimulation factors. Instead, our studies demonstrate that soil bacteria are essential for triggering germination. Through 16s rRNA amplicon sequencing analysis, we found that certain carbon sources and nitrate can reshape the initial microbial community to an inducing community leading to the germination of P. brassicae resting spores. The stimulating communities significantly differed in composition and abundance of bacterial taxa compared to the non-stimulating ones. Several enriched bacterial taxa in stimulating community were significantly correlated with spore germination rates and may be involved as stimulation factors. Based on our findings, a multi-factorial ‘pathobiome’ model comprising abiotic and biotic factors is proposed to represent the putative plant-microbiome-pathogen interactions associated with breaking spore dormancy of P. brassicae in soil. This study presents novel views on P. brassicae pathogenicity and lays the foundation for novel sustainable control strategies of clubroot. 相似文献
60.