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51.
北京放射性核束装置在线同位素分离器(BRISOL)采用100 MeV、200 μA回旋加速器提供的质子束打靶产生中、短寿命放射性核束,在线分析后供物理用户使用,其质量分辨率好于20 000。为开展20Na核的奇异衰变特性研究,研制了氧化镁靶,并采用100 MeV质子束轰击氧化镁靶在线产生了20~26Na+的钠同位素放射性核束。当质子束流强为8 μA时,20Na+离子束的最大产额为2×105 s-1,21Na+离子束的最大产额为4×108 s-1。完成了北京放射性核束装置首个放射性核束物理实验,累计供束近200 h。 相似文献
52.
SANHUA LI QINGHONG KONG XIAOKE ZHANG XINTING ZHU CHUNBO YU CHANGYAN YU NIAN JIANG JING HUI LINGJIE MENG YUN LIU 《Biocell》2022,46(11):2425-2432
Traditional Chinese medicine (TCM) has been increasingly employed in the last decades in China for both preventing and treating a variety of cancers. 3-epi-bufotalin is an active ingredient of TCM “Chanpi” with anti-tumor potential. However, the effect and mechanism of 3-epi-bufotalin on colorectal cancers were not well disclosed. The present study demonstrated that 3-epi-bufotalin could reduce viability, trigger apoptosis, and block the cell cycle at the G2/M stage in colorectal cancer cell lines HT29, RKO, and COLO205 in vitro. Moreover, 3-epi-bufotalin inhibited the JAK1/STAT3 signaling pathway. These results indicated the anti-proliferation ability of 3-epi-bufotalin in colorectal cancer cells. 相似文献
53.
JONG HWAN SUNG 《Biocell》2022,46(5):1177-1180
Organ-on-a-chip technology aims to reproduce the key physiological features of human organs and tissues, even complex actions of multi-organ interaction. While organ-on-a-chips at single-organ level has made notable achievement during the last decade, multi-organ-on-a-chips, which manifests unique advantages, has started gathering attention only recently. In this viewpoint, we discuss the current status of organ-on-a-chip technology, with a specific emphasis on multi-organ-on-a-chip. Key technological advances contributing to the maturation of the field, and challenges that need to be addressed before wider adoption in relevant fields are discussed. We will share our perspectives on how the multi-organ-on-a-chip can improve the drug development process. 相似文献
54.
FRANCESCO PADUANO EMANUELA ALTOMARE BENEDETTA MARRELLI VINCENZO DATTILO HAIZAL MOHD HUSSAINI PAUL ROY COOPER MARCO TATULLO 《Biocell》2022,46(8):1827-1835
Oral Cancer (OC) is one of the most recurrent cancers in the head and neck squamous cancer (SCCHN)
category. Recently, the genome-wide association studies (GWAS) have gained growing interest in the scientific
community. GWAS have identified several pathways involved in the interactions among general risk factors and
genomic variants affecting SCCHN. This systematic overview aims to critically evaluate the latest data reported within
the scientific literature. The aim was to investigate the impact of genetic aspects on SCCHN onset and prognosis,
involving other clinical and systemic co-factors. PubMed, Google Scholar, and Cancer Genetics Web databases have
been systematically investigated for original articles published in the last two years, reporting studies on the main
queries addressed in this work. This review also comparatively describes the impact of environmental and
pathological co-factors in different types of cancers, clarifying and updating the role of genetic factors in SCCHN
onset and development. The main outcomes reported may be helpful to drive clinicians towards their clinical
evaluations for the most appropriate therapeutic approach in SCCHN. 相似文献
55.
We investigated the diversity and composition of microflora in feces of Lycopus lucidus Turcz.-fed mice. In
addition, we evaluated the production of major cytokines (Interleukin-6 and -10) which are related to inflammation
and fatty acid composition of several tissues. 16S ribosomal DNA sequencing-based microbiome taxonomic profiling
analysis was performed utilizing the EzBioCloud data base. Male mice fed on L. lucidus showed a significantly
reduced number of lactic acid bacteria and coliform in the feces compared with the control group (p < 0.05). 16S
rDNA sequencing analysis of fecal samples showed that L. lucidus supplementation decreased the community of
harmful microflora (Enterobacteriaceae including Escherichia coli and Bacteroides sp.) in feces compared with the
control group (p < 0.05). There were no significant differences in mRNA expression of cytokine IL-6 and IL-10
between the control and L. lucidus fed groups. The fecal fatty acid composition in the L. lucidus group had
percentages of 4:0, 6:0, 8:0 and 10:0 in the intestine but those short chain fatty acids were not detected in the control
group. Our results showed that L. lucidus supplementation influenced gut environment by decreasing harmful
microflora and increased the percentages of several short fatty acids. 相似文献
56.
Hazelnut husk brown rot has been identified as a new disease in Liaoning Province in recent years. The objective of this study as to identify the pathogen. [Method] In this study, a standard sample of hazelnut husk brown rot was collected from Songmudao Base in Dalian City, Liaoning Province. The pathogen was identified by the studies of the morphology, pathogenicity, and analyses of ITS and LSU sequences. The pathogen was isolated and purified, which was confirmed by Koch’s postulates. The symptoms after inoculation were the same as those collected directly from a diseased tree, which showed that it was the pathogenic fungus. The cultural characteristics and conidia and the morphology of the pathogenic fungi were similar to those of Botrytis cinerea’s. The ITS sequences and LSU sequences were compared to the associated strain sequences in GenBank, with 100% identity to Botrytis cinerea (GenBank accession number: MN589848.1) and Botrytis cinerea (GenBank accession number: KU140653.1), respectively. The infection status of the pathogen on the hazelnut husks was also observed. The studies suggested that the pathogen leading to the hazelnut husk brown rot as a new disease in Liaoning Province was Botrytis cinerea. 相似文献
57.
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59.
236Pu的含量控制是钚热源的一项重要参数,通过α能谱准确测量镎靶溶解液中痕量236Pu,建立镎靶辐照靶件溶解液中钚的分离方法。根据杂质组成特点采用TBP-TEVA萃取色层双柱分离,用氨基磺酸亚铁以及亚硝酸钠对钚进行调价,对靶件溶解液中的Al、Fe、U、Th和Np等进行分离,去污系数均大于104,钚的回收率为90.7%。研究大量238Pu对α能谱测定236Pu的干扰,结果表明,大量238Pu会造成仪器本底升高,238Pu能谱峰分辨率降低;在7 500 Bq 238Pu干扰下,测量4.3 h 时,236Pu的最小可检测活度为1.20×10-2 Bq(当量质量为6.11×10-16 g)。计算结果表明,镎靶溶解液样品中钚的同位素比值n(236Pu)/n(238Pu) ≥4.63×10-8时,取合适的样品量使得电沉积源中238Pu 活度在 450~7 500 Bq范围内,均可测量其中的痕量236Pu,同时可准确测定同位素比值n(236Pu)/n(238Pu)。 相似文献
60.
陈超 《计算机工程与应用》2019,55(12):124-131
鉴于高斯混合模型对背景变化快时无法精确检测出目标和目标跟踪的适应性差等瑕疵,提出了基于加权似然跟踪器来改进高斯混合模型实现运动目标跟踪算法。主要引入了自适应高斯混合模型来实时检测运动目标,然后空间加权似然来进行视频中的目标定位,引入加权似然期望值来改进高斯混合模型处理视频中的多尺度、多角度变化的目标跟踪不精准问题。通过VOT 2014 dataset对比实验结果表明提出的基于加权似然跟踪(Weighted Likelihood Tracking,WLT)和改进高斯混合模型(Improved Gaussian Mixture Model,IGMM)的目标跟踪算法较传统高斯混合模型跟踪算法在跟踪的精度有较大提高。在应对多尺度、多角度变化的目标跟踪表现出了较大的优势。 相似文献