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A comprehensive profile of TCF1^(+)progenitor and TCF1−terminally exhausted PD-1^(+)CD8^(+)T cells in head and neck squamous cell carcinoma:implications for prognosis and immunotherapy 被引量:1
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作者 Dikan Wang Juan Fang +14 位作者 Shuqiong Wen Qunxing Li Jinming Wang Lisa Yang Wenxiao Dai Huanzi Lu junyi guo Zhongyan Shan Wenqiang Xie Xiangqi Liu Liling Wen Jie Shen Anxun Wang Qianming Chen Zhi Wang 《International Journal of Oral Science》 SCIE CAS CSCD 2022年第1期91-99,共9页
The heterogeneity of exhausted T cells(Tex)is a critical determinant of immune checkpoint blockade therapy efficacy.However,few studies have explored exhausted T cell subpopulations in human cancers.In the present stu... The heterogeneity of exhausted T cells(Tex)is a critical determinant of immune checkpoint blockade therapy efficacy.However,few studies have explored exhausted T cell subpopulations in human cancers.In the present study,we examined samples from two cohorts of 175 patients with head and neck squamous cell cancer(HNSCC)by multiplex immunohistochemistry(mIHC)to investigate two subsets of Tex,CD8+PD1+TCF1+progenitor exhausted T cells(TCF1+Texprog)and CD8+PD1+TCF1−terminally exhausted T cells(TCF1−Texterm).Moreover,fresh tumor samples from 34 patients with HNSCC were examined by flow cytometry and immunohistochemistry to further investigate their properties and cytotoxic capabilities and their correlation with regulatory T cells(Tregs)in the tumor immune microenvironment(TIME).mIHC and flow cytometry analysis showed that TCF1−Texterm represented a greater proportion of CD8+PD1+Tex than TCF1+Texprog in most patients.TCF1+Texprog produced abundant TNFα,while TCF1−Texterm expressed higher levels of CD103,TIM-3,CTLA-4,and TIGIT.TCF1−Texterm exhibited a polyfunctional TNFα+GZMB+IFNγ+phenotype;and were associated with better overall survival and recurrence-free survival.The results also indicated that larger proportions of TCF1−Texterm were accompanied by an increase in the proportion of Tregs.Therefore,it was concluded that TCF1−Texterm was the major CD8+PD1+Tex subset in the HNSCC TIME and that these cells favor patient survival.A high proportion of TCF1−Texterm was associated with greater Treg abundance. 展开更多
关键词 PD1 PROGENITOR SQUAMOUS
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通货膨胀风险下关于累积阶段的固定缴费养老金的均值-方差问题 被引量:7
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作者 张笑怡 郭军义 《中国科学:数学》 CSCD 北大核心 2019年第3期607-620,共14页
本文研究了在通货膨胀环境下关于累积阶段的固定缴费(de?ned contribution, DC)养老金的一个均值-方差问题.一般来说, DC养老金的管理周期比较长,所以,本文考虑了养老金的实际财富过程,而非名义财富过程,并且假设价格指数的动态过程包... 本文研究了在通货膨胀环境下关于累积阶段的固定缴费(de?ned contribution, DC)养老金的一个均值-方差问题.一般来说, DC养老金的管理周期比较长,所以,本文考虑了养老金的实际财富过程,而非名义财富过程,并且假设价格指数的动态过程包含一个跳-扩散过程.通过投资金融市场上的三种产品(无风险银行账户、通胀指数债券和风险资产),该DC养老金最优管理的目标是在给定期望的前提下最小化终端时间的方差.风险资产同样包含一个跳-扩散过程.通过解相关的Hamilton-Jacobi-Bellman (HJB)方程,本文得到了最优的投资策略以及相关的有效前沿的显式表达. 展开更多
关键词 POISSON过程 DC养老金 随机最优控制 均值-方差问题 HJB方程
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Expression of ipt gene driven by tomato fruit specific promoter and its effects on fruit development of tomato 被引量:6
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作者 Zichao Mao Qiuju Yu +4 位作者 Wei Zhen junyi guo Yuanlei Hu Yin Gao Zhongping Lin 《Chinese Science Bulletin》 SCIE EI CAS 2002年第11期928-933,969,共7页
Fruit specific promoter (2A12) from Lycopersi-com esculentum and cDNA of isopentenyl-transferase (ipt) from Ti plasmid of Agrobacterium tumerfaciens C58 were cloned by PCR procedure respectively. Two plant expression ... Fruit specific promoter (2A12) from Lycopersi-com esculentum and cDNA of isopentenyl-transferase (ipt) from Ti plasmid of Agrobacterium tumerfaciens C58 were cloned by PCR procedure respectively. Two plant expression vectors with 2A12/gus or 2A12/ipt were respectively constructed. These two chimeric genes were transferred into tomato by Agrobacterium mediated procedure. The results of Southern hybridization showed that the fusion genes had been integrated into tomatoes. The result of gus histochemi-cal staining showed that 2A12 had high fruit specific expressive capability in transgenic tomato. The ipt expression resulted in accumulation of high level of cytokinins (CTKs) in fruit lead to developmental changes in fruits and seeds. The fruit of ipt transformed tomato had the hyperplastic placenta with very few seeds or even seedless. The shelf life of transgenic fruits elongated for 1-2 weeks. The ratio of fruit set, the dry weight of fruit and the crude protein content in fruit were increased, while 展开更多
关键词 TOMATO 2A12 FRUIT SPECIFIC PROMOTER IPT GENE CTKs.
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两个保险公司的最优合并时刻问题
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作者 李亚男 柏立华 郭军义 《中国科学:数学》 CSCD 北大核心 2019年第1期89-106,共18页
Gerber和Shiu(2006)将两个公司的合并可行性问题与最优分红策略问题联系起来,给出公司合并会产生效益的条件,并提出一个更现实的问题:若选择合并,最优合并时刻是什么?本文分两步研究了这个问题.首先,利用混合奇异/二维最优停止理论,证... Gerber和Shiu(2006)将两个公司的合并可行性问题与最优分红策略问题联系起来,给出公司合并会产生效益的条件,并提出一个更现实的问题:若选择合并,最优合并时刻是什么?本文分两步研究了这个问题.首先,利用混合奇异/二维最优停止理论,证明相应的验证定理,然后分两种情形讨论了这个问题.最终得到的最优策略为:情形1下不可能合并,两个公司分别采取最有利于自己的分红策略;情形2下,整个区域被分成3部分U_1、U_2和U_3,最优策略取决于两公司的盈余落在哪个区域.若落在区域U_1,最优策略同情形1;若落在区域U_3,两公司马上合并,合并后的公司采取它的最优分红策略;若落在区域U_2,两公司不分红并等待,直到其盈余过程到达U_1或U_3,然后,施行如上所述的合并和分红策略. 展开更多
关键词 最优合并时刻 最优分红 最优停止理论 HJB(Hamilton-Jacob-Bellman)方程 隐函数存在定理
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OPTIMAL INVESTMENT AND PROPORTIONAL REINSURANCE IN THE SPARRE ANDERSEN MODEL 被引量:1
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作者 Zhibin LIANG junyi guo 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2012年第5期926-941,共16页
From the insurer's point of view, this paper studies the optimal investment and proportional reinsurance in the Sparre Andersen model. Under the criterion of maximizing the adjustment coefficient, the authors obtain ... From the insurer's point of view, this paper studies the optimal investment and proportional reinsurance in the Sparre Andersen model. Under the criterion of maximizing the adjustment coefficient, the authors obtain the closed form expressions of the optimal strategy and the maximal adjustment coefficient, and derive the explicit expression of the ruin probability or its lower bound when the claim sizes are exponentially distributed. Some numerical examples are presented, which show the impact of model parameters on the optimal values. It can also be seen that the optimal strategy to maximize the adjustment coefficient is sometimes equivalent to those which minimize the ruin probability. 展开更多
关键词 Adjustment coefficient INVESTMENT proportional reinsurance ruin probability SparreAndersen model.
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