强耦合振子可用于微弱脉冲信号的检测和波形恢复,但其对微弱脉冲信号的检测频率会受到系统内置频率的限制.在系统内置频率固定的情况下,系统只能对一定频率范围内的脉冲信号进行有效检测和波形恢复,在检测更高频率的脉冲信号时会出现波...强耦合振子可用于微弱脉冲信号的检测和波形恢复,但其对微弱脉冲信号的检测频率会受到系统内置频率的限制.在系统内置频率固定的情况下,系统只能对一定频率范围内的脉冲信号进行有效检测和波形恢复,在检测更高频率的脉冲信号时会出现波形失真.本文分析了耦合振子内置频率和微弱脉冲信号检测频率之间的关系,提出两种改进强耦合振子结构以扩展微弱脉冲信号的频率检测范围.通过引入非线性恢复力耦合项,非线性恢复力强耦合振子可以有效保留信号的高频分量,在更高频率的脉冲信号输入时也能较好地保留信号特征.双振子强耦合系统通过引入Van der Pol-Duffing振子,加强了系统内部结构的稳定性,同样达到了扩展脉冲信号频率检测范围的效果.此外,基于变迭代步长和混沌检测的频率相关性,提出了一个未知频率脉冲信号检测方法,以改变迭代步长的方法代替改变系统内置频率来进行频率扫描,并且利用混沌检测的频率相关性,将接收信号和恢复信号的相关系数和纯噪声输入情况下的相关系数进行对比,根据两个相关系数之间的明显差异可以有效检测出脉冲信号.通过仿真实验进行验证,所提方法可以有效检测出未知频率的脉冲信号,并且所提的改进强耦合振子结构相对于强耦合振子有较大的性能提升.展开更多
Specific oligonucleotides such as telomere DNA and aptamer often undergo conformational changes upon ligand binding. Composite reagent composed of o-phthalaldehyde and β-mercaptoethanol（OPAME） has been extensively ...Specific oligonucleotides such as telomere DNA and aptamer often undergo conformational changes upon ligand binding. Composite reagent composed of o-phthalaldehyde and β-mercaptoethanol（OPAME） has been extensively applied to fluorescent detection of amino compounds based on the reaction of primary amino-group, herein we proposed a general spectrofluorometry for ions and small molecules due to conformational changes upon ligand binding taking K^＋ and ATP as examples. In a borate controlled buffer medium, telomere DNA could react with OPAME, giving a thio-subtituted isoindole compound with strong fluorescence emission at 455 nm when excited at 340 nm. It was found that however, the fluorescence emission was greatly reduced in the presence of K^＋ since the formation of the quadruplex structure inhibits the reaction activity of amino-groups of telomere DNA. In order to testify the general application of OPAME reagent based on the conformational change of oligonucleotides, we further proposed a sensitive method of ATP based on its highly selective interaction with ATP-aptamer. The above mentioned applications show that the spectrofluorometry with the aid of OPAME reagent is simple, label free that is expected to be potentially general for DNA conformational change-based target detection.展开更多
目的通过Meta分析探讨在儿童及青少年成熟B细胞非霍奇金淋巴瘤治疗中应用利妥昔单抗联合化疗的疗效与安全性,为更加合理地应用利妥昔单抗提供理论依据。方法检索PubMed、Embase、Cochrane Library、ClinicalTrials.gov、Web of Science...目的通过Meta分析探讨在儿童及青少年成熟B细胞非霍奇金淋巴瘤治疗中应用利妥昔单抗联合化疗的疗效与安全性,为更加合理地应用利妥昔单抗提供理论依据。方法检索PubMed、Embase、Cochrane Library、ClinicalTrials.gov、Web of Science、中国知网、万方、维普数据库的文献,共筛选出从建库至2022年6月公开发表的利妥昔单抗治疗儿童及青少年成熟B细胞非霍奇金淋巴瘤的10篇文献,共计886例患儿。以3年无事件生存率、3年总生存率、完全缓解率、病死率和不良反应发生率作为结局指标,采用RevMan 5.4软件进行Meta分析、亚组分析、敏感性分析和发表偏倚分析。结果与单纯化疗组相比,利妥昔单抗联合化疗组3年无事件生存率显著提高(HR=0.38,95%CI:0.25~0.59,P<0.001),3年总生存率显著提高(HR=0.29,95%CI:0.14~0.61,P=0.001),完全缓解率显著提高(OR=3.72,95%CI:1.89~7.33,P<0.001),病死率显著降低(OR=0.31,95%CI:0.17~0.57,P<0.001)。而两组的不良反应发生率差异无统计学意义(OR=1.28,95%CI:0.85~1.92,P=0.24)。结论在儿童及青少年成熟B细胞非霍奇金淋巴瘤治疗方案中添加利妥昔单抗可带来明显的生存益处,且不会增加不良反应的发生。展开更多
【目的/意义】对国外开放数据研究进行较为全面系统的分析,呈现国外开放数据的研究现状、热点和趋势。【方法/过程】以Web of Science核心合集数据库为数据源,以1999~2019年国外期刊发表的1448篇论文为样本,选取发表时间、作者、机构、...【目的/意义】对国外开放数据研究进行较为全面系统的分析,呈现国外开放数据的研究现状、热点和趋势。【方法/过程】以Web of Science核心合集数据库为数据源,以1999~2019年国外期刊发表的1448篇论文为样本,选取发表时间、作者、机构、国家、期刊、关键词作为变量,并运用Citespace可视化软件,对这些论文的分布特征、关键词共现、关键词聚类以及突现词进行分析。【结果/结论】研究发现,国外开放数据研究热点聚焦在数据共享、开放政府数据、机器学习、链接数据等方面,研究前沿体现在各学科开放数据的数据库资源分类和开放数据的各类风险问题。展开更多
Background In both the seventh edition of the International Union Against Cancer （UICC） staging system for gastric cancer and the 14th edition of the Japanese Gastric Cancer Association （JGCA） system, T4a is defin...Background In both the seventh edition of the International Union Against Cancer （UICC） staging system for gastric cancer and the 14th edition of the Japanese Gastric Cancer Association （JGCA） system, T4a is defined as ＂Tumor perforates serosa （visceral peritoneum） without invasion of adjacent structures.＂ The aim of this study was to investigate the differences in prognosis between patients with serosa-penetrating and serosa-invading T4aN0M0 gastric carcinomas. Methods Data were collected from 221 patients with T4aNoMo gastric carcinoma who underwent D2 resection at our cancer center between January 1990 and December 2008. The cohort included 42 patients with serosa-penetrating tumors and 179 patients with serosa-invading tumors. The average follow-up time was 85.5 months. Spearman＇s rank correlation, Kaplan-Meier plots, and Cox proportional hazards regression models were used to analyze the data. Results The 5-year survival rate of patients with serosa-penetrating and serosa-invading gastric cancers were 31% and 62% respectively （P 〈0.05）. The relapse rates after D2 radical surgery were 16.2% in patients with serosa-invading gastric cancer versus 59.5% in those with serosa-penetrating tumors （P 〈0.05）. Peritoneal dissemination and distant organ/lymph node metastatic rates were 76.0% and 24.0% respectively in patients with penetrating tumors, versus 44.8% and 55.2% respectively in patients with invading tumors （P 〈0.05）. Multivariate analysis showed that penetration of the serosa was an independent prognostic indicator of overall survival. Conclusions Our findings provide a basis for the concept that serosa-penetrating TaaNoMo gastric carcinoma represents a more aggressive cancer than serosa-invading T4aN0M0 gastric carcinoma. Serosa penetration is an independent factor for poor prognosis of patients with gastric carcinoma.展开更多
文摘强耦合振子可用于微弱脉冲信号的检测和波形恢复,但其对微弱脉冲信号的检测频率会受到系统内置频率的限制.在系统内置频率固定的情况下,系统只能对一定频率范围内的脉冲信号进行有效检测和波形恢复,在检测更高频率的脉冲信号时会出现波形失真.本文分析了耦合振子内置频率和微弱脉冲信号检测频率之间的关系,提出两种改进强耦合振子结构以扩展微弱脉冲信号的频率检测范围.通过引入非线性恢复力耦合项,非线性恢复力强耦合振子可以有效保留信号的高频分量,在更高频率的脉冲信号输入时也能较好地保留信号特征.双振子强耦合系统通过引入Van der Pol-Duffing振子,加强了系统内部结构的稳定性,同样达到了扩展脉冲信号频率检测范围的效果.此外,基于变迭代步长和混沌检测的频率相关性,提出了一个未知频率脉冲信号检测方法,以改变迭代步长的方法代替改变系统内置频率来进行频率扫描,并且利用混沌检测的频率相关性,将接收信号和恢复信号的相关系数和纯噪声输入情况下的相关系数进行对比,根据两个相关系数之间的明显差异可以有效检测出脉冲信号.通过仿真实验进行验证,所提方法可以有效检测出未知频率的脉冲信号,并且所提的改进强耦合振子结构相对于强耦合振子有较大的性能提升.
基金Supported by the National Natural Science Foundation of China(No.20775061)
文摘Specific oligonucleotides such as telomere DNA and aptamer often undergo conformational changes upon ligand binding. Composite reagent composed of o-phthalaldehyde and β-mercaptoethanol（OPAME） has been extensively applied to fluorescent detection of amino compounds based on the reaction of primary amino-group, herein we proposed a general spectrofluorometry for ions and small molecules due to conformational changes upon ligand binding taking K^＋ and ATP as examples. In a borate controlled buffer medium, telomere DNA could react with OPAME, giving a thio-subtituted isoindole compound with strong fluorescence emission at 455 nm when excited at 340 nm. It was found that however, the fluorescence emission was greatly reduced in the presence of K^＋ since the formation of the quadruplex structure inhibits the reaction activity of amino-groups of telomere DNA. In order to testify the general application of OPAME reagent based on the conformational change of oligonucleotides, we further proposed a sensitive method of ATP based on its highly selective interaction with ATP-aptamer. The above mentioned applications show that the spectrofluorometry with the aid of OPAME reagent is simple, label free that is expected to be potentially general for DNA conformational change-based target detection.
文摘目的通过Meta分析探讨在儿童及青少年成熟B细胞非霍奇金淋巴瘤治疗中应用利妥昔单抗联合化疗的疗效与安全性,为更加合理地应用利妥昔单抗提供理论依据。方法检索PubMed、Embase、Cochrane Library、ClinicalTrials.gov、Web of Science、中国知网、万方、维普数据库的文献,共筛选出从建库至2022年6月公开发表的利妥昔单抗治疗儿童及青少年成熟B细胞非霍奇金淋巴瘤的10篇文献,共计886例患儿。以3年无事件生存率、3年总生存率、完全缓解率、病死率和不良反应发生率作为结局指标,采用RevMan 5.4软件进行Meta分析、亚组分析、敏感性分析和发表偏倚分析。结果与单纯化疗组相比,利妥昔单抗联合化疗组3年无事件生存率显著提高(HR=0.38,95%CI:0.25~0.59,P<0.001),3年总生存率显著提高(HR=0.29,95%CI:0.14~0.61,P=0.001),完全缓解率显著提高(OR=3.72,95%CI:1.89~7.33,P<0.001),病死率显著降低(OR=0.31,95%CI:0.17~0.57,P<0.001)。而两组的不良反应发生率差异无统计学意义(OR=1.28,95%CI:0.85~1.92,P=0.24)。结论在儿童及青少年成熟B细胞非霍奇金淋巴瘤治疗方案中添加利妥昔单抗可带来明显的生存益处,且不会增加不良反应的发生。
基金The National Key Research and Development Program of China(2018YFC1602600)the National Natural Science Foundation of China(21974109)+1 种基金the Fundamental Research Funds for the Central Universities(XDJK2019TY003)the Fund of Chongqing Research Program of Basic Research and Frontier Technology(cstc2017jcyjAX0091)。
文摘【目的/意义】对国外开放数据研究进行较为全面系统的分析,呈现国外开放数据的研究现状、热点和趋势。【方法/过程】以Web of Science核心合集数据库为数据源,以1999~2019年国外期刊发表的1448篇论文为样本,选取发表时间、作者、机构、国家、期刊、关键词作为变量,并运用Citespace可视化软件,对这些论文的分布特征、关键词共现、关键词聚类以及突现词进行分析。【结果/结论】研究发现,国外开放数据研究热点聚焦在数据共享、开放政府数据、机器学习、链接数据等方面,研究前沿体现在各学科开放数据的数据库资源分类和开放数据的各类风险问题。
文摘Background In both the seventh edition of the International Union Against Cancer （UICC） staging system for gastric cancer and the 14th edition of the Japanese Gastric Cancer Association （JGCA） system, T4a is defined as ＂Tumor perforates serosa （visceral peritoneum） without invasion of adjacent structures.＂ The aim of this study was to investigate the differences in prognosis between patients with serosa-penetrating and serosa-invading T4aN0M0 gastric carcinomas. Methods Data were collected from 221 patients with T4aNoMo gastric carcinoma who underwent D2 resection at our cancer center between January 1990 and December 2008. The cohort included 42 patients with serosa-penetrating tumors and 179 patients with serosa-invading tumors. The average follow-up time was 85.5 months. Spearman＇s rank correlation, Kaplan-Meier plots, and Cox proportional hazards regression models were used to analyze the data. Results The 5-year survival rate of patients with serosa-penetrating and serosa-invading gastric cancers were 31% and 62% respectively （P 〈0.05）. The relapse rates after D2 radical surgery were 16.2% in patients with serosa-invading gastric cancer versus 59.5% in those with serosa-penetrating tumors （P 〈0.05）. Peritoneal dissemination and distant organ/lymph node metastatic rates were 76.0% and 24.0% respectively in patients with penetrating tumors, versus 44.8% and 55.2% respectively in patients with invading tumors （P 〈0.05）. Multivariate analysis showed that penetration of the serosa was an independent prognostic indicator of overall survival. Conclusions Our findings provide a basis for the concept that serosa-penetrating TaaNoMo gastric carcinoma represents a more aggressive cancer than serosa-invading T4aN0M0 gastric carcinoma. Serosa penetration is an independent factor for poor prognosis of patients with gastric carcinoma.
