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A Comparative Study on the Effect of BCG-PSN and Thymopeptides on T-lymphocyte Subsets of Normal and Immunosuppressed Mice 被引量:12
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作者 邓云华 陈映玲 +2 位作者 陈兴平 李永喜 周礼义 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2003年第4期339-343,347,共6页
To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG PSN) and thymopeptides on T lymphocytes of normal and immunosuppressed mice, CD4 + and CD8 + T lymphocyte subsets of... To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG PSN) and thymopeptides on T lymphocytes of normal and immunosuppressed mice, CD4 + and CD8 + T lymphocyte subsets of single nucleic cell in thymus, spleen and peripheral blood were detected successively by flow cytometry after application of BCG PSN and thymopeptides. Meanwhile, CD4 +/CD8 + ratio was also calculated. The results showed that both BCG PSN and thymopeptides could decrease the proportion of CD4 + CD8 + T lymphocyte subsets in the thymus, at the same time increase CD4 + T lymphocyte, CD8 +T lymphocyte proportion in the three tissues. The fluctuation in amplitude was greater in thymopeptides group than that in BCG PSN group. It is concluded that acting location of thymopeptides is in thymus, its stimulating action is stronger than that of BCG PSN, while BCG PSN not only accelerates the differentiation in thymus, but also has some direct stimulation to peripheral CD4 +T lymphocytes, and can maintain CD4 +/CD8 + ratio within normal range. So, BCG PSN is safer. 展开更多
关键词 polysaccharide nucleic acid fraction of bacillus calmette guerin thymopeptides t-lymphocyte CD4 +/CD8 + ratio CD4 + t-lymphocyte CD8 + t-lymphocyte
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Distribution of natural killer cells and T-lymphocyte subsets in peripheral blood,gallbladder cancer and surrounding tissue 被引量:12
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作者 Liu, Gang Ren, Hong +1 位作者 Sun, Xue-Jun Shi, Jing-Sen 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第1期81-86,共6页
BACKGROUND: The patient with malignant tumor always show immunologic function drawback and ingravescent with tumor development, especially in the aspect of cell-mediated immunity. This study was undertaken to define t... BACKGROUND: The patient with malignant tumor always show immunologic function drawback and ingravescent with tumor development, especially in the aspect of cell-mediated immunity. This study was undertaken to define the relationship between the immune function of local cells and cancer development by investigating the distribution of natural killer (NK) cells and T-lymphocyte subsets in peripheral blood, the cancer tissue and the tissue surrounding gallbladder carcinoma. METHODS: The numbers of CD4(+) and CD8(+) T-lymphocytes and NK cells were measured by flow cytometry in samples taken from gallbladder cancer tissue, the surrounding tissues and peripheral blood of 38 patients, and compared with the numbers in the peripheral blood and gallbladder tissue of 30 patients with cholecystitis as controls. RESULTS: The numbers of CD4(+) and CD8(+) T-cells and NK cells in gallbladder cancer tissues were significantly higher than those in the surrounding tissue and gallbladder with gallstone. However, the ratio of CD4(+)/CD8(+) was lower in the cancer tissue than that in the surrounding tissue and tissue from gallbladders with gallstones. The distribution of CD4(+) and CD8(+) T-cells and NK cells in mucous membrane of cholecystitis gallbladder and that in the tissue surrounding gallbladder cancer were significantly different. CONCLUSIONS: Disproportionate and imbalanced distribution of NK cells and subsets of T-lymphocytes occurs in the mucous membrane proper of gallbladder cancer and surrounding tissue. Although gallbladder cancer tissue has higher expressions of CD4(+), CD8(+) and NK cells, the immune function is low or in an inhibited state. In gallbladder cancer immunization therapy, local cellular immunological function should be enhanced and the protective barrier improved. 展开更多
关键词 gallbladder cancer t-lymphocyte subset natural killer cell
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Effects of Intraoperative Administration of Dexmedetomidine on the Percentage of T-Lymphocyte Subsets and Natural Killer Cells in Patients with Colorectal Cancer 被引量:5
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作者 Tonghang Zhao Zhong Liu +1 位作者 Ailan Yu Zongwang Zhang 《Open Journal of Anesthesiology》 2013年第2期104-108,共5页
Study Objective: To observe the effect of dexmedetomidine (DEX) on T-lymphocyte subsets and natural killer (NK) cells in the peripheral blood of perioperative patients with colorectal cancer. Design: A random double-b... Study Objective: To observe the effect of dexmedetomidine (DEX) on T-lymphocyte subsets and natural killer (NK) cells in the peripheral blood of perioperative patients with colorectal cancer. Design: A random double-blind control clinical study. Setting: A university hospital. Patients: Forty patients with colorectal cancer, ASA I-П. Interventions: All patients were randomly divided into a DEX group (n = 20) and a control group (n = 20). Before induction of anesthesia, epidural catheters were placed in the L1-L2 or T12-L1 intervertebral spaces. The DEX group received 1 μg/kg of DEX (200 μg/50 ml) intravenously for 15 min prior to the surgery, which was then infused at a rate of 0.5 μg/kg/h until 30 min before the end of the surgery. The control group received an intravenous infusion of saline (50 ml) instead of DEX during the same periods as the DEX group. All patients received routine anesthesia and postoperative analgesia. Measurements: Blood samples from all patients were collected at the following time points: before anesthesia (T0), 24 h after surgery (T1), 48 h after surgery (T2) and 72 h after surgery (T3). Changes in T-lymphocyte subsets (CD3+, CD4+, CD8+, CD4+/CD8+) and NK cells were determined by flow cytometry. Main Results: Compared with the control group, the percentages of CD3+ and CD4+ cells and the CD4+/CD8+ ratio in the DEX group increased significantly from T1 to T3 展开更多
关键词 DEXMEDETOMIDINE t-lymphocyte SUBSETS Natural KILLER Cell Colorectal Cancer Surgery
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Effect of cytotoxic T-lymphocyte antigen-4,TNF-alpha polymorphisms on osteosarcoma: evidences from a meta-analysis 被引量:3
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作者 Jianwei Liu Junli Wang +1 位作者 Weiping Jiang Yujin Tang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第6期671-678,共8页
Objective: Previous studies have investigated the role of cytotoxic T-lymphocyte antigen-4 (CTLA-4) and tumor necrosis factor-alpha (TNF-a) in carcinogenesis of osteosarcoma, but their results were inconsistent. ... Objective: Previous studies have investigated the role of cytotoxic T-lymphocyte antigen-4 (CTLA-4) and tumor necrosis factor-alpha (TNF-a) in carcinogenesis of osteosarcoma, but their results were inconsistent. We aimed to clarify the associations between CTLA-4, TNF-a polymorphism and osteosarcoma risk by using meta-analysis. Methods: We searched relevant studies without language restriction in PubMed, EMbase, Cochrane Library, Google Scholar databases, Chinese National Knowledge Infrastructure (CNKI) and conference literature in humans published prior to March 2013. The strengths of the associations between genetic variants and osteosarcoma risk were estimated by odds ratio (OR) with 95% confidence interval (95% CI). Results: A total of seven studies with 1,198 osteosarcoma patients and 1,493 controls were selected. Four studies were eligible for CTLA-4 (1,003 osteosarcoma and 1,162 controls), and three studies for TNF-a (195 osteosarcoma and 331 controls). Pooled results showed that rs231775 polymorphism of CTLA-4 was associated with osteosarcoma risk (GG vs. AA: OR=1.63, 95% CI=1.24-2.13; GG + GA vs. AA: OR=1.56, 95% CI=1.21-2.01; AA + GA vs. GG: OR=0.83, 95% CI=0.71-0.97; G vs. A: OR=1.21, 95% CI=1.08-1.36). No significant heterogeneity was observed across the studies. No significant associations were found between rs5742909 polymorphism of CTLA-4 or rs1800629 polymorphism of TNF-a and osteosarcoma risk. Conclusions: These results suggest that the rs231775 polymorphism of CTLA-4 may play an important role in carcinogenesis of osteosarcoma. 展开更多
关键词 Cytotoxic t-lymphocyte antigen-4 (CTLA-4) tumor necrosis factor-alpha (TNF-a) OSTEOSARCOMA genetic polymorphism
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Analysis of T-lymphocyte subtypes of the peripheral blood and skindelayed-type hypersensitivity in patients with hyper-IgE syndrome
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作者 XiaobingLei ShengshunTan WeihuiZeng JunminWang PanjianZhang YuanYuan 《Journal of Nanjing Medical University》 2005年第2期99-101,共3页
Objective: To study the function of ce ll ular immunity in patients with hyper-IgE syndrome (HIE). Methods: T-lymphocyte subtypes of the peripheral blood and cutaneous delayed-typ e hypersensitivity (DTH) response ... Objective: To study the function of ce ll ular immunity in patients with hyper-IgE syndrome (HIE). Methods: T-lymphocyte subtypes of the peripheral blood and cutaneous delayed-typ e hypersensitivity (DTH) response to two recall antigens, tetanus toxoid (TT) an d purified protein derivative(PPD), were measured in five patients with HIE and 15 healthy controls, respectively. Results: The CD4+ cell cou nts in HIE group were significantly lower than those in control group (P<0. 01). In contrast, CD8+ cells were significantly higher than those in the contro l (P<0.01). The induration sizes of DTH response to two recall antigens wer e smaller in HIE group than those in the control group (P<0.01). Co nclusion: There was an immunologic dysfunction of T lymphocytes in the p atients with HIE. 展开更多
关键词 Hyper-IgE Syndrome t-lymphocyte subtypes delayed-type hypersensitivity
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Research of T-lymphocytes apoptosis and levels of T-lymphocyte subtypes in donors of donated blood many times
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《中国输血杂志》 CAS CSCD 2001年第S1期323-,共1页
关键词 Research of t-lymphocytes apoptosis and levels of t-lymphocyte subtypes in donors of donated blood many times
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Effects of Heat Clearing and Stasis Resolving Method on PTS,Inflammatory Factors and T-lymphocyte Subsets in Peripheral Blood of URM Patients with Suppressed Internal Heat
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作者 Fenqin ZHAO Jieying LIU +2 位作者 Yan ZHAO Yajiao GOU Zhixia HU 《Medicinal Plant》 CAS 2022年第4期34-38,共5页
[Objectives]To explore the effects of heat clearing and stasis resolving method on prethrombotic state,inflammatory factors and T-lymphocyte subsets in peripheral blood of unexplained recurrent miscarriage(URM)patient... [Objectives]To explore the effects of heat clearing and stasis resolving method on prethrombotic state,inflammatory factors and T-lymphocyte subsets in peripheral blood of unexplained recurrent miscarriage(URM)patients with suppressed internal heat.[Methods]Thirty cases of URM patients with suppressed internal heat and 30 normal women were collected,and characteristics of changes in peripheral serum D-dimer(D-D),fibrin degradation product(FDP),fibrinogen(FIB),IL-6,IL-10 and TNF-α,CD,CD,CD,CD,CDlevels were detected.URM patients were treated with traditional Chinese medicine for clearing heat and resolving blood stasis for 3 menstrual cycles,and the changes of indicators before and after treatment were observed.[Results]Compared with normal women,the peripheral serum levels of D-D,IL-6,TNF-αand CDin URM patients with suppressed internal heat were increased(P<0.05),while the IL-10 lymphocyte level was significantly decreased(P<0.05);compared with that before treatment,the contents of D-D,IL-6,TNF-αand CDdecreased after 3 menstrual cycles(P<0.05),while the contents of IL-10 and CDT lymphocytes increased significantly(P<0.05).[Conclusions]The heat clearing heat and stasis resolving method can effectively improve the prethrombotic state of URM,and the action mechanism may be related to the regulation of immune and peripheral blood inflammatory factors. 展开更多
关键词 Unexplained recurrent miscarriage(URM) Suppressed internal heat type Prethrombotic state(PTS) Heat clearing and stasis resolving Inflammatory factors t-lymphocyte subsets
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(α,γ)-Anti-Multi-Fuzzy Subgroups and Some of Its Properties
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作者 Memet Sahin Vakkas Uluçay +2 位作者 S.A.Edalatpanah Fayza Abdel Aziz Elsebaee Hamiden Abd El-Wahed Khalifa 《Computers, Materials & Continua》 SCIE EI 2023年第2期3221-3229,共9页
Recently,fuzzy multi-sets have come to the forefront of scientists’interest and have been used in algebraic structures such asmulti-groups,multirings,anti-fuzzy multigroup and(α,γ)-anti-fuzzy subgroups.In this pape... Recently,fuzzy multi-sets have come to the forefront of scientists’interest and have been used in algebraic structures such asmulti-groups,multirings,anti-fuzzy multigroup and(α,γ)-anti-fuzzy subgroups.In this paper,we first summarize the knowledge about the algebraic structure of fuzzy multi-sets such as(α,γ)-anti-multi-fuzzy subgroups.In a way,the notion of anti-fuzzy multigroup is an application of anti-fuzzy multi sets to the theory of group.The concept of anti-fuzzy multigroup is a complement of an algebraic structure of a fuzzy multi set that generalizes both the theories of classical group and fuzzy group.The aim of this paper is to highlight the connection between fuzzy multi-sets and algebraic structures from an anti-fuzzification point of view.Therefore,in this paper,we define(α,γ)-antimulti-fuzzy subgroups,(α,γ)-anti-multi-fuzzy normal subgroups,(α,γ)-antimulti-fuzzy homomorphism on(α,γ)-anti-multi-fuzzy subgroups and these been explicated some algebraic structures.Then,we introduce the concept(α,γ)-anti-multi-fuzzy subgroups and(α,γ)-anti-multi-fuzzy normal subgroups and of their properties.This new concept of homomorphism as a bridge among set theory,fuzzy set theory,anti-fuzzy multi sets theory and group theory and also shows the effect of anti-fuzzy multi sets on a group structure.Certain results that discuss the(α,γ)cuts of anti-fuzzy multigroup are explored. 展开更多
关键词 Fuzzy set anti-fuzzy multi set anti-fuzzy multi subgroup anti-fuzzy multi normal subgroup
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基于网络群组特征的生态管理分区--以武汉市为例
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作者 何建华 袁毅 +2 位作者 张苗苗 覃荣诺 陈志朋 《生态学报》 CAS CSCD 北大核心 2024年第4期1514-1525,共12页
生态管理分区是维持区域生态安全、实现城市生态差异化治理的重要手段。然而现有分区方法侧重生态功能属性,较少考虑生态斑块之间联系强度差异,忽视了斑块的群组结构。以武汉市为例构建生态网络,从生态系统结构和功能的视角,结合斑块空... 生态管理分区是维持区域生态安全、实现城市生态差异化治理的重要手段。然而现有分区方法侧重生态功能属性,较少考虑生态斑块之间联系强度差异,忽视了斑块的群组结构。以武汉市为例构建生态网络,从生态系统结构和功能的视角,结合斑块空间组织和斑块联系强弱,运用凝聚子群方法,提取联系紧密的生态组分,将网络划分为异质性群组,基于网络群组特征和生态景观辐射范围进行分区覆盖分析,并进行分区评价。结果表明:(1)86条生态廊道连接研究区34处生态斑块,进一步形成8个生态群组;(2)多数群组内部连通性较好,北部群组之间联系较强,南部群组之间联系相对较弱;(3)依据群组结构功能特征,形成6大网络群组分区,通过与武汉市经济发展规划分区对比,两者具有较高的一致性;(4)城市外围的分区网络稳定性较好,中部稳定性较差,识别分区内13个重要斑块和16条重要廊道,作为重点发展保护对象;(5)综合分区特征将6大分区确立为生态屏障区、生态控制区、生态改善区、生态修复区、生态开发区以及生态保育区,并提出生态发展差异化保护措施。研究将生态功能属性和空间结构属性进行有机关联并制定分区策略,为区域生态管理分区、生态保护规划提供新视角。 展开更多
关键词 生态分区 生态网络 凝聚子群 网络群组 武汉市
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ABO基因第7外显子c.539G>C突变致A_(2)B亚型结果分析
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作者 黄颖 胡思群 +1 位作者 温郑静 林甲进 《温州医科大学学报》 CAS 2024年第3期233-235,共3页
目的:探讨ABO基因第7外显子c.539G>C突变致A_(2)B亚型结果分析。方法:采用试管凝集法检测ABO血型,采用Sanger测序法进行基因测序及序列分析。结果:4例先证者红细胞为A弱B表型,根据血清学特征定义为A_(2)B血型,先证者1、3、4血清中无... 目的:探讨ABO基因第7外显子c.539G>C突变致A_(2)B亚型结果分析。方法:采用试管凝集法检测ABO血型,采用Sanger测序法进行基因测序及序列分析。结果:4例先证者红细胞为A弱B表型,根据血清学特征定义为A_(2)B血型,先证者1、3、4血清中无抗-A_(1)抗体;先证者2血清中存在抗-A_(1)抗体;4例血型基因型为ABO^(*)A2.08/ABO^(*)B.01,测序结果与A102基因序列比对,A208在c.467C>T和c.539G>C位发生突变,导致多肽链P156L和R180P替换。结论:α-1,3-N-乙酰半乳糖胺转移酶基因c.539G>C突变产生A208表型。 展开更多
关键词 ABO血型 A_(2)亚型 基因突变
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智能算法的亚群优化策略综述
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作者 杜晓昕 周薇 +4 位作者 王浩 郝田茹 王振飞 金梅 张剑飞 《计算机应用》 CSCD 北大核心 2024年第3期819-830,共12页
群智能算法的优化是提升群智能算法性能的一个主要途径,随着群智能算法越来越广泛地运用到各类模型优化、生产调度、路径规划等问题中,对智能算法性能的要求也越来越高。亚群策略作为一种优化群智能算法的重要手段,能够灵活地平衡算法... 群智能算法的优化是提升群智能算法性能的一个主要途径,随着群智能算法越来越广泛地运用到各类模型优化、生产调度、路径规划等问题中,对智能算法性能的要求也越来越高。亚群策略作为一种优化群智能算法的重要手段,能够灵活地平衡算法的全局勘探能力和局部开发能力,已经成为群智能算法的研究热点之一。为了促进亚群优化策略的发展和应用,对动态亚群策略、基于主从范式的亚群策略和基于网络结构的亚群策略进行了详细调查,阐述了各类亚群策略的结构特点、改进方式和应用场景。最后,总结了亚群策略目前存在的问题以及未来的研究趋势和发展方向。 展开更多
关键词 粒子群优化算法 群智能算法 动态亚群策略 主从范式 网络结构
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参杞强精颗粒对慢性疲劳综合征脾肾阳虚证大鼠免疫调节作用研究
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作者 卢秋玉 刘金花 +3 位作者 宾彬 赖克道 魏海斌 唐爱存 《世界中医药》 CAS 北大核心 2024年第7期969-974,共6页
目的:探讨参杞强精颗粒对慢性疲劳综合征(CFS)脾肾阳虚证模型大鼠的影响以及免疫调节作用。方法:将50只无特定病原体(SPF)级健康雄性斯泼累格·多雷(SD)大鼠随机分为正常对照组,模型对照组,参杞强精颗粒高剂量组、中剂量组、低剂量... 目的:探讨参杞强精颗粒对慢性疲劳综合征(CFS)脾肾阳虚证模型大鼠的影响以及免疫调节作用。方法:将50只无特定病原体(SPF)级健康雄性斯泼累格·多雷(SD)大鼠随机分为正常对照组,模型对照组,参杞强精颗粒高剂量组、中剂量组、低剂量组,采用游泳力竭实验造成大鼠体力疲劳,慢性束缚应激造成大鼠心理疲劳,同时给予番泻叶煎煮液灌胃造成脾肾阳虚证候,构建CFS脾肾阳虚证大鼠模型,造模成功后分别按照各组剂量灌胃,连续给药21 d后,测定各组大鼠的胸腺和脾脏指数,酶联免疫吸附试验(ELISA)检测血清免疫球蛋白G(IgG)、免疫球蛋白M(IgM)、免疫球蛋白A(IgA)浓度以及细胞因子白细胞介素2(IL-2)、白细胞介素6(IL-6)和γ干扰素(IFN-γ)含量,MTT法检测脾脏T、B淋巴细胞增殖能力,流式细胞法检测各组大鼠外周血T淋巴细胞亚群分布情况。结果:行为学结果显示,模型大鼠的体质量增长缓慢,精神萎靡,摄食水量减少,活动减少,便质稀软,力竭游泳时间减少,悬尾静止时间增加。药物干预后,与模型组比较,各给药组大鼠精神状态、体质量、摄食水量均显著改善,力竭游泳时间增加、悬尾静止时间减少(P<0.01或P<0.05);参杞强精颗粒各剂量组能显著提升大鼠胸腺和脾脏指数,提高IgG、Ig M、IgA浓度和IL-2、IL-6、IFN-γ的含量,显著提高脾脏T、B淋巴细胞增殖能力,也能提高CD3+、CD4+T淋巴细胞百分率和CD4+/CD8+T比值,降低CD8+T淋巴细胞百分率,差异有统计学意义(P<0.01或P<0.05)。结论:参杞强精颗粒能显著改善慢性疲劳综合征脾肾阳虚证大鼠免疫功能,缓解疲劳症状,且具有很好的免疫调节作用。 展开更多
关键词 参杞强精颗粒 慢性疲劳综合征 脾肾阳虚证 免疫调节 免疫球蛋白 T淋巴细胞亚群 大鼠
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T淋巴细胞亚群和肝功能指标与慢性乙型肝炎患者中医辨证分型的相关性
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作者 吴林军 周翼 +1 位作者 蒲文杰 刘于嵩 《检验医学》 CAS 2024年第2期166-170,共5页
目的 分析T淋巴细胞亚群和肝功能指标与慢性乙型肝炎(CHB)患者中医辨证分型的相关性,为临床中医辨证分型、治疗方案选择和疗效观察提供科学依据。方法 选取2020年1—12月乐山市中医医院983例CHB患者,其中中医辩证分型实证270例(湿热中阻... 目的 分析T淋巴细胞亚群和肝功能指标与慢性乙型肝炎(CHB)患者中医辨证分型的相关性,为临床中医辨证分型、治疗方案选择和疗效观察提供科学依据。方法 选取2020年1—12月乐山市中医医院983例CHB患者,其中中医辩证分型实证270例(湿热中阻证75例、瘀血阻络证195例)、虚证713例(肝郁脾虚证662例、肝肾阴虚证28例、脾肾阳虚证23例)。检测各证型患者肝功能相关指标[丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、总蛋白(TP)、白蛋白(Alb)、总胆红素(TB)、直接胆红素(DBil)]和T细胞(CD3~+、CD4~+、CD8~+)计数,分析各项指标与CHB中医证型的相关性。结果 肝郁脾虚证、瘀血阻络证、湿热中阻证、肝肾阴虚证、脾肾阳虚证临床CHB频率依次升高。CHB各证型中,脾肾阳虚证患者年龄最大,湿热中阻证患者年龄最小。各证型间肝功能相关指标和T淋巴细胞计数差异均有统计学意义(P<0.05);CD3~+、CD4~+T细胞计数与湿热中阻证呈正相关(P<0.05),与脾肾阳虚证呈负相关(P<0.05)。结论 T淋巴细胞亚群和肝功能相关指标与CHB患者中医辨证分型存在相关性,可为临床中医辨证分型、治疗方案选择和疗效观察提供客观依据。 展开更多
关键词 T淋巴细胞亚群 肝功能 慢性乙型肝炎 中医辨证分型
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基于PCA-ShapeDTW-QWGRU的分布式光伏集群短期功率预测
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作者 欧阳静 秦龙 +3 位作者 王坚锋 尹康 褚礼东 潘国兵 《太阳能学报》 EI CAS CSCD 北大核心 2024年第5期458-467,共10页
针对分布式光伏短期功率预测建立基于主成分分析、改进的动态时间规整算法与量子加权门控循环单元(PCAShapeDTW-QWGRU)的集群功率预测模型。针对集群划分不够精细、光伏电站数据蕴含的信息难以捕捉的问题,提出基于主成分分析结合密度聚... 针对分布式光伏短期功率预测建立基于主成分分析、改进的动态时间规整算法与量子加权门控循环单元(PCAShapeDTW-QWGRU)的集群功率预测模型。针对集群划分不够精细、光伏电站数据蕴含的信息难以捕捉的问题,提出基于主成分分析结合密度聚类算法(PCA-OPTICS)的集群划分方法;针对目前选取代表电站与集群相似性较低的问题,提出基于改进的动态时间规整算法(ShapeDTW)的代表电站的选取方法,利用ShapeDTW度量相似性距离,选取最小值作为代表电站,并利用基于均方根传播梯度下降法优化的量子加权门控循环单元(RMSprop-QWGRU)模型进行预测;为了解决代表电站与集群功率的变换系数转换差异较大的问题,采用实时变换系数对代表电站进行集群功率值预测计算。实验结果表明,所提方法能有效提升光伏集群功率预测的精度。 展开更多
关键词 光伏功率预测 集群划分 主成分分析 动态时间规整 量子加权门控循环单元
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关于线性子空间的并集的一个注记
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作者 史江涛 王燕 《高等数学研究》 2024年第1期1-2,15,共3页
设V是一个线性空间,不考虑V上的数量乘法运算和加法运算满足的交换律,则V构成一个群.给出了一个群V可以写成三个真子群的并集的充分必要条件.
关键词 线性空间 子空间 并集 子群
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居民财产分配差异测度研究——基于基尼系数群组和来源的二维分解方法
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作者 刘学良 《南开经济研究》 北大核心 2024年第5期198-216,共19页
本文提出一个新的基尼系数二维分解方法,该方法可以同时进行基尼系数的按群组和按来源分解操作,从而避免了不平等的群组分解和来源分解因使用方法不同而难以融合的缺陷。基于此方法,本文使用CFPS数据测算了2012—2020年我国城乡居民财... 本文提出一个新的基尼系数二维分解方法,该方法可以同时进行基尼系数的按群组和按来源分解操作,从而避免了不平等的群组分解和来源分解因使用方法不同而难以融合的缺陷。基于此方法,本文使用CFPS数据测算了2012—2020年我国城乡居民财产分配差距,发现这一时期居民财产分配差距呈波动上升态势。其中,城乡内部特别是城镇内部居民持有住房资产的差异是这一时期财产分配不平等扩大的重要原因,但如果考虑扣除房贷后的净资产,则其对差距扩大贡献明显缩小;而城乡间差异不是导致居民总体财产差距扩大的原因,其中,土地资产在这一时期起到扩大城乡组间差距的效果,而住房资产及住房净资产起到缩小组间差距的作用。因此,十八大以来,农村居民住房条件和住房财产明显提高对于缓解城乡差异起到积极作用,但不可忽视的是,城乡间住房资产和住房条件的绝对差距仍然很大,缩小城乡间居民住房条件差距仍然任重道远。 展开更多
关键词 基尼系数 群组分解 来源分解 二维分解 财产分配差距
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J、K亚群禽白血病病毒的分离和囊膜蛋白(gp85)基因序列分析
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作者 周钊灿 游广炬 +4 位作者 杨金易 苏晓娜 高丽 王永强 郑世军 《中国兽医杂志》 CAS 北大核心 2024年第4期1-10,共10页
为了解现阶段我国禽白血病病毒(ALV)的流行特征和演化趋势,本试验于2021—2022年从国内某鸡场采集蛋清ALV衣壳蛋白(p27)抗原阳性的鸡血浆,接种鸡胚成纤维细胞(DF-1)分离病毒并进行亚群鉴定;采用聚合酶链式反应(PCR)技术扩增分离株的囊... 为了解现阶段我国禽白血病病毒(ALV)的流行特征和演化趋势,本试验于2021—2022年从国内某鸡场采集蛋清ALV衣壳蛋白(p27)抗原阳性的鸡血浆,接种鸡胚成纤维细胞(DF-1)分离病毒并进行亚群鉴定;采用聚合酶链式反应(PCR)技术扩增分离株的囊膜蛋白(gp85)基因片段,并对其进行测序,将基因序列与ALV不同亚群毒株进行比对和遗传进化分析;选取氨基酸变化差异较大的分离毒株进行间接免疫荧光鉴定。结果显示,共分离到7株ALV毒株(3株J亚群,4株K亚群),ALV-J分离毒株CAU4932、CAU4860和CAU2259的gp 85基因片段长度为918 bp,编码306个氨基酸,分离毒株之间gp 85基因核苷酸同源性为90.5%~95.2%,gp85蛋白氨基酸同源性为95.1%~99.3%;ALV-K分离毒株CAU7049、CAU5006、CAU7176和CAU7168的gp 85基因片段长度为1008 bp,编码336个氨基酸,分离毒株之间gp 85基因核苷酸同源性为89.4%~92.3%,gp85蛋白氨基酸同源性为94.0%~99.7%。gp85蛋白氨基酸序列同源性比对发现,分离株gp85蛋白氨基酸序列均会发生突变,但高变区hr1和hr2所占比例较多,证实了gp85的高变性。在gp85蛋白B细胞抗原表位中存在部分位点的氨基酸突变,可能导致gp85蛋白抗原性发生变化。间接免疫荧光鉴定结果显示,5株分离毒株均可在DF-1细胞内复制并存在可被抗体识别的p27抗原表位。结果表明,本试验分离的7株ALV毒株是国内ALV-J和ALV-K流行毒株的突变株,不仅丰富了ALV基因组库资源,且为后续研究ALV的遗传变异特征和流行趋势等提供参考依据。 展开更多
关键词 禽白血病病毒 J亚群 K亚群 gp 85基因 序列比较
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董事会群体断裂带与企业并购——基于分类-加工理论视角的研究
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作者 张章 陈仕华 《财贸研究》 北大核心 2024年第4期57-72,共16页
从董事会子群体特征的视角出发,基于分类-加工理论,选取2008-2019年间沪深A股上市公司为样本,考察董事会关系型群体断裂带与任务型群体断裂带对企业并购决策以及并购绩效的影响。研究发现:(1)董事会中关系型群体断裂带越强,企业进行并... 从董事会子群体特征的视角出发,基于分类-加工理论,选取2008-2019年间沪深A股上市公司为样本,考察董事会关系型群体断裂带与任务型群体断裂带对企业并购决策以及并购绩效的影响。研究发现:(1)董事会中关系型群体断裂带越强,企业进行并购的可能性越低;董事会中任务型群体断裂带越强,企业进行并购的可能性越高。(2)董事会中关系型群体断裂带越强,企业取得的并购绩效越差;董事会中任务型群体断裂带越强,企业取得的并购绩效越好。(3)董事会成员的平均任期能够减弱董事会关系型群体断裂带对企业并购决策以及并购绩效的消极影响,并减弱任务型群体断裂带对企业并购决策以及并购绩效的积极影响。(4)行业竞争程度能够弱化董事会关系型群体断裂带对企业并购决策以及并购绩效的消极影响,增强董事会任务型群体断裂带对企业并购决策以及并购绩效的积极影响。 展开更多
关键词 子群体 董事会群体断裂带 分类-加工理论 并购
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E3泛素连接酶FBXL8对A亚群禽白血病病毒复制的影响
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作者 郑诗龄 陈雪阳 +3 位作者 刘晶 方春 梁雄燕 杨玉莹 《中国畜牧兽医》 CAS CSCD 北大核心 2024年第4期1696-1705,共10页
【目的】制备鸡E3泛素连接酶FBXL8多克隆抗体,探究鸡源FBXL8对A亚群禽白血病病毒(Avian leukosis virus subgroup A,ALV-A)在鸡胚成纤维细胞(DF-1)内复制的影响。【方法】以DF-1细胞cDNA为模板,通过PCR扩增FBXL 8基因,构建鸡源FBXL8原... 【目的】制备鸡E3泛素连接酶FBXL8多克隆抗体,探究鸡源FBXL8对A亚群禽白血病病毒(Avian leukosis virus subgroup A,ALV-A)在鸡胚成纤维细胞(DF-1)内复制的影响。【方法】以DF-1细胞cDNA为模板,通过PCR扩增FBXL 8基因,构建鸡源FBXL8原核表达重组质粒pET-28a-FBXL8,将其转化大肠杆菌表达菌株RIL进行诱导表达及纯化,将表达产物His-FBXL8免疫10月龄新西兰大白兔制备多克隆抗体,利用Western blotting和间接ELISA分别检测抗体特异性及效价;针对已公布的FBXL 8基因序列设计过表达引物及靶向FBXL 8基因的干扰序列,构建过表达质粒psi-flag-FBXL8及干扰质粒pLKO.1-FBXL8-shRNA,使用Western blotting检测其表达效果。将构建成功的过表达质粒和干扰质粒转染DF-1细胞,24 h后感染ALV-A,通过半定量PCR、Western blotting分别检测ALV-A的结构蛋白P27、GP85表达水平。【结果】PCR成功扩增出大小为1182 bp的FBXL 8基因片段,并成功构建FBXL8原核表达重组质粒pET-28a-FBXL8,诱导表达的融合蛋白His-FBXL8大小为43 ku。Western blotting和间接ELISA结果显示,制备的FBXL8兔多克隆抗体可特异性识别外源蛋白,且抗体效价为1∶64000。成功构建了FBXL8过表达质粒和干扰质粒,其在DF-1细胞中能够实现对FBXL8的过表达和敲低。半定量PCR和Western blotting检测结果显示,过表达FBXL8可抑制ALV-A复制,而敲低FBXL8则促进其复制。【结论】本研究制备的FBXL8多克隆抗体具有良好特异性及反应性;在DF-1细胞中,FBXL8负向调控ALV-A复制,研究结果为进一步深入探究FBXL8生物学特性提供了重要参考,并为揭示FBXL8抗ALV-A感染分子机制奠定了基础。 展开更多
关键词 FBXL8 A亚群禽白血病病毒(ALV-A) 多克隆抗体 病毒复制
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关于有限群的自中心的非亚循环子群的TI-性和次正规性
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作者 李娜 史江涛 《纯粹数学与应用数学》 2024年第2期212-217,共6页
对于自中心的非亚循环子群,本文把它们的TI-性和次正规性结合在一起证明了:如果有限群G的每个自中心的非亚循环子群皆为TI-子群或次正规子群,则G的每个非亚循环子群皆次正规于G,而且这类群是可解的.此外,本文还证明了如果有限群G的每个... 对于自中心的非亚循环子群,本文把它们的TI-性和次正规性结合在一起证明了:如果有限群G的每个自中心的非亚循环子群皆为TI-子群或次正规子群,则G的每个非亚循环子群皆次正规于G,而且这类群是可解的.此外,本文还证明了如果有限群G的每个自中心的非亚循环子群皆为TI-子群,则G的每个自中心的非亚循环子群皆在G中正规. 展开更多
关键词 非亚循环子群 自中心 TI-子群 次正规子群 可解
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