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七叶总皂苷及其中A B C D组分的抗炎作用实验研究 被引量:2
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作者 田晓丽 《辽宁中医药大学学报》 CAS 2009年第2期175-177,共3页
目的:药理研究和临床应用均证明,七叶总皂苷具有消炎的作用。目前对从七叶总皂苷中提取分离得到的A、B、C、D4种单组分的药理研究和临床应用尚未见报道。实验旨在研究A、B、C、D组分的药理作用并初步探讨其作用机制。通过与七叶总皂苷... 目的:药理研究和临床应用均证明,七叶总皂苷具有消炎的作用。目前对从七叶总皂苷中提取分离得到的A、B、C、D4种单组分的药理研究和临床应用尚未见报道。实验旨在研究A、B、C、D组分的药理作用并初步探讨其作用机制。通过与七叶总皂苷进行比较,从中筛选出疗效优于总皂苷和(或)毒副作用低于总皂苷的单组分,为进一步开发成新药提供前期的理论依据。 展开更多
关键词 七叶总皂苷 七叶皂苷A b c D 抗炎
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CD4^+CXCR5^+ T cells activate CD27^+IgG^+ B cells via IL-21 in patients with hepatitis C virus infection 被引量:4
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作者 Fan-Yun Kong Bo Feng +4 位作者 Heng-Hui Zhang Hui-Ying Rao Jiang-Hua Wang Xu Cong Lai Wei 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2016年第1期55-64,共10页
BACKGROUND: Chronic hepatitis C virus (HCV) infection causes the skewing and activation of B cell subsets, but the characteristics of IgG+ B cells in patients with chronic hepa- titis C (CHC) infection have not ... BACKGROUND: Chronic hepatitis C virus (HCV) infection causes the skewing and activation of B cell subsets, but the characteristics of IgG+ B cells in patients with chronic hepa- titis C (CHC) infection have not been thoroughly elucidated. CD4+CXCR5+ follicular helper T (Tfh) cells, via interleukin (IL)-21 secretion, activate B cells. However, the role of CD4+CXCR5+ T cells in the activation ofIgG+ B cells in CHC patients is not clear. METHODS: The frequency of IgG+ B cells, including CD27-IgG+ B and CD27+IgG+ B cells, the expression of the activation markers (CD86 and CD95) in IgG+ B cells, and the percentage of circu- lating CD4+CXCR5+ T cells were detected by flow cytometry in CHC patients (n=70) and healthy controls (n=25). The con- centrations of serum IL-21 were analyzed using ELISA. The role of CD4+CXCR5+ T cells in the activation of IgG+ B cells was investigated using a co-culture system. RESULTS: A significantly lower proportion of CD27+IgG+ B cells with increased expression of CD86 and CD95 was observed in CHC patients. The expression of CD95 was negatively correlated with the percentage of CD27+IgG+ B cells, and it contributed to CD27+IgG+ B cell apoptosis. Circulating CD4+CXCR5+ T cells and serum IL-21 were significantly increased in CHC patients. Moreover, circulating CD4+CXCR5+ T cells from CHC patients induced higher expressions of CD86 and CD95 in CD27+IgG+ B cells in a co-culture system; the blockade of the IL-21 decreased the expression levels of CD86 and CD95 in CD27+IgG+ B cells.CONCLUSIONS: HCV infection increased the frequency of CD4+CXCR5+ T cells and decreased the frequency of CD27+IgG+ B cells. CD4+CXCR5+ T cells activated CD27+IgG+ B cells via the secretion of IL-21. 展开更多
关键词 chronic hepatitis c IgG+ b cells cD4+cXcR5+ T cells
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Expression and clinical value of programmed cell death-ligand 1(PD-L1)in diffuse large B cell lymphoma:a retrospective study 被引量:13
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作者 Li-Yang Hu Xiao-Lu Xu +7 位作者 Hui-Lan Rao Jie Chen Ren-Chun Lai Hui-Qiang Huang Wen-Qi Jiang Tong-Yu Lin Zhong-Jun Xia Qing-Qing Cai 《Chinese Journal of Cancer》 SCIE CAS CSCD 2017年第12期767-777,共11页
Background: The programmed cell death-1(PD-1)/programmed cell death-ligand 1(PD-L1) pathway inhibits the activation of T cells and plays a crucial role in the negative regulation of cellular and humoral immune respons... Background: The programmed cell death-1(PD-1)/programmed cell death-ligand 1(PD-L1) pathway inhibits the activation of T cells and plays a crucial role in the negative regulation of cellular and humoral immune responses.Diffuse large B-cell lymphoma(DLBCL) is the most common lymphoid malignancy in adults. In the present study, we aimed to detect the expression of PD-L1 in DLBCL and to analyze its relationship with prognosis.Methods: We reviewed medical records of 204 newly diagnosed DLBCL patients in Sun Yat-sen University Cancer Center between October 2005 and August 2012. The expression of PD-L1 in tumor tissues from these 204 patients was detected using immunohistochemical(IHC) assay. The expression of anaplastic lymphoma kinase(ALK), CD5,CD30, and C-Myc in tumor specimens from 109 patients was detected using IHC, and Epstein-Barr virus(EBV)-encoded RNAs(EBERs) were detected using fluorescence in situ hybridization. The Spearman method was used for correlation analysis. The Kaplan-Meier method with log-rank test was used for univariate analysis. Cox proportional hazards model was used for multivariate analysis.Results: Of the 204 patients, 100(49.0%) were PD-L1-positive in tumor cells and 44(21.6%) were PD-L1-positive in tumor microenvironment. PD-L1 expression in tumor cells and tumor microenvironment were more common in the non-germinal center B-cell-like(GCB) subtype than in the GCB subtype(P = 0.02 and P= 0.04). Patients with PD-L1 expression in tumor microenvironment were more likely to be resistant to first-line chemotherapy when compared with the patients without PD-L1 expression in tumor microenvironment(P = 0.03). PD-L1 expression in tumor microenvironment was negatively correlated with C-Myc expression(r =-0.20, P = 0.04). No correlations were detected between PD-L1 expression and the expression of ALK, CD5, and CD30 as well as EBERs. The 5-year overall survival(OS)rates were 50.0% and 67.3% in patients with and without PD-L1 expression in tumor cells(P = 0.02). PD-L1 expression in tumor cells was an independent risk predictor for OS(P < 0.01).Conclusions: PD-L1 expression is more common in the non-GCB subtype than in the GCB subtype. PD-L1 expression in tumor microenvironment has a negative correlation with C-Myc. PD-L1 positivity predicts short survival in DLBCL patients. For patients with PD-L1 expression, more strategy such as anti-PD-L1 antibody treatment should be recommended. 展开更多
关键词 Programmed cell death-ligand 1 (PD-L1) DIFFUSE large b-cELL LYMPHOMA c-Myc Prognosis
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The Diagnostic and Prognostic Impact of Serum miRNA-21 in a Sample of Hepatitis C/None Hepatitis Diffuse Large B Cell Lymphoma Egyptian Patients 被引量:1
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作者 Nabil El-Halawani Aida Nazir +2 位作者 Nagwa Mashali Amani Sorour Mayada A. Moussa 《American Journal of Molecular Biology》 2017年第1期49-72,共24页
Background: Circulating microRNAs are potential biomarkers of diagnostic and prognostic impact in various inflammatory and malignant diseases. Aim: Linking inflammation with malignancy, we studied miRNA-21 in sera of ... Background: Circulating microRNAs are potential biomarkers of diagnostic and prognostic impact in various inflammatory and malignant diseases. Aim: Linking inflammation with malignancy, we studied miRNA-21 in sera of hepatitis-C-virus (HCV) and none hepatitis diffuse large B-cell lymphoma (DLBCL) patients, aiming to identify its differential expression and prognosis in DLBCL with its subtypes;germinal center B-cell (GCB) and activated B-cell-like (ABC) and to evaluate its relation with HCV. Subjects and Methods: MiRNA-21 expression was measured using TaqMan quantitative RT-PCR in sera of 30 newly diagnosed DLBCL patients (HCV positive (n = 10), HCV negative (n = 20)) and 20 controls (HCV positive (n = 10), HCV negative (n = 10)). Results: MiRNA-21 expression was significantly higher in DLBCL patients than in control (p = 0.00). Significant positive correlations between miRNA-21 and LDH, IPI and disease stage were detected (p Conclusion: Our study shows that miRNA-21 is over expressed in our patients with DLBCL, displaying higher levels in ABC than in GCB subtypes. MiRNA-21 is associated with poor response to treatment and survival in DLBCL. MiRNA-21 is a potential marker of necro-inflammation independent of its role in tumorogenesis, showing higher expression in HCV positive DLBCL patients compared to none hepatitis patients. 展开更多
关键词 Diffuse Large b-cELL Lymphoma MIcRORNA-21 HEPATITIS c Virus Germinal center-b Activated b-cell-Like
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Hepatitis C virus-related B cell subtypes in non Hodgkin's lymphoma 被引量:4
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作者 Adriano M Pellicelli Massimo Marignani +15 位作者 Valerio Zoli Mario Romano Aldo Morrone Lorenzo Nosotti Giuseppe Barbaro Antonio Picardi Umberto Vespasiani Gentilucci Daniele Remotti Cecilia D'Ambrosio Caterina Furlan Fabrizio Mecenate Ettore Mazzoni Ignazio Majolino Roberto Villani Arnaldo Andreoli Giorgio Barbarini 《World Journal of Hepatology》 CAS 2011年第11期278-284,共7页
AIM:To evaluate if indolent B cell-non Hodgkin's lymphoma(B-NHL) and diffuse large B-cell lymphoma(DLBCL) in hepatitis C virus(HCV) positive patients could have different biological and clinical characteristics re... AIM:To evaluate if indolent B cell-non Hodgkin's lymphoma(B-NHL) and diffuse large B-cell lymphoma(DLBCL) in hepatitis C virus(HCV) positive patients could have different biological and clinical characteristics requiring different management strategies.METHODS:A group of 24 HCV related B-NHL patients(11 indolent,13 DLBCL) in whom the biological and clinical characteristics were described and confronted.Patients with DLBCL were managed with the standard of care of treatment.Patients with indolent HCV-related B-NHL were managed with antiviral treatment pegylated interferon plus ribavirin and their course observed.The outcomes of the different approaches were compared.RESULTS:Patients with DLBCL had a shorter duration of HCV infection and a higher prevalence of HCV genotype 1 compared to patients with indolent B-NHL in which HCV genotype 2 was the more frequent genotype.Five of the 9 patients with indolent HCV-relatedB-NHL treated with only antiviral therapy,achieved a complete response of their onco-haematological disease(55%).Seven of the 13 DLBCL patients treated with immunochemotheraphy obtained a complete response(54%).CONCLUSION:HCV genotypes and duration of HCV infection differed between B-NHL subtypes.Indolent lymphomas can be managed with antiviral treatment,while DLBCL is not affected by the HCV infection. 展开更多
关键词 Hepatitis c virus infection Diffuse large b cell LYMPHOMA INDOLENT LYMPHOMA Pegylated INTERFERON LYMPHOMAGENESIS
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Diagnostic and Prognostic Value of Nuclear Factor Kappa-B in Diffuse Large B Cell Lymphoma in Egyptian Patients with Hepatitis C Virus Genotype 4
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作者 Nabil El Halawani Manal El Sordi +2 位作者 Mona Aiad Bassma El Sabaa Alia Hashim 《American Journal of Molecular Biology》 2019年第3期121-143,共23页
Background: Members of the NFκB [p65] family have potential diagnostic and prognostic role in various inflammatory diseases and Lymphomas. Aim: We studied NFκB [p65] in paraffin blocks of hepatitis-C-virus [HCV] pos... Background: Members of the NFκB [p65] family have potential diagnostic and prognostic role in various inflammatory diseases and Lymphomas. Aim: We studied NFκB [p65] in paraffin blocks of hepatitis-C-virus [HCV] positive genotype-4 and HCV negative diffuse large B-cell lymphoma [DLBCL] patients, aiming at identification of its differential expression and prognosis in DLBCL and its subtypes;GCB and ABC. This is to establish its relation to HCV infection and its role in lymphogenesis. Besides assessing the role of new directly acting antiviral drugs [Sofusbuvir/Ledipasvir] concomitantly administered to [CHOP] combination in HCV positive DLBCL. Subjects and Methods: NFκB [p65] expression was assessed using Anti-NFκB [p65] antibody semi-quantitative technique in 30 newly diagnosed DLBCL patients [HCV positive [n = 15], HCV negative [n = 15]. Results: NFκB [p65] expression was higher in the HCV positive DLBCL patients than their HCV negative counterpart, with a positive correlation with the viral load [r = 0.536, p = 0.088]. NFκB [p65] expression was significantly more frequently detected in the ABC subtype than GCB subtype [p = 0.04]. Patients who expressed NFκB [p65] had higher incidence of extranodal involvement, advanced stages, higher LDH levels and IPI score. Besides, the expression of NFκB [P65] revealed an inferior overall response [OR] [p = 0.044]. Higher complete response rates to CHOP concomitantly with antiviral [ledipasvir/sofosbuvir] were encountered in the HCV positive group. In HCV positive group, NFκB [P65] displayed a positive relationship with the viral load and liver enzymes [p = 0.04], besides an inverse relation with serum albumin. This raises the possibility that NFκB [p65] expression is suggestive of the hepatic necro-inflammation in HCV patients. The ABC group presented more in advanced stages than GCB. Higher frequency of the ABC subgroup exhibited intermediate to high viral load, while it was less in the GCB. A statistically significant difference was found in the NFκB [p65] positive patients as regards MUM1 expression among the two groups [p ≤ 0.001]. Double positive [CD10+, MUM1+] and triple negative [CD10-, BCL6-, MUM1-] cases were encountered in the HCV positive group, and were characterized with a high NFκB [p65] expression. Conclusion: NFκB [p65] is expressed in patients with DLBCL, more frequently in ABC than in GCB subtypes. Expression of NFκB [p65] is associated with poor response to therapy in DLBCL. The NFκB [p65] disclosed an increased expression in HCV positive DLBCL compared to HCV negative group. The viral load displayed a positive correlation with the NFκB [p65] expression. Simultaneous administration of DAAs in combination with CHOP disclosed a better response and high tolerability. 展开更多
关键词 DIFFUSE Large b-cELL LYMPHOMA NF-κb HEPATITIS c Virus Germinal center-b Activated b-cell-Like ANTIVIRAL Therapy
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北斗三号MEO卫星B1C/B2a信号单系统精密产品性能评估
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作者 王乐 陆文龙 +3 位作者 解世超 冯瑞瑞 张奋 崔博斌 《测绘地理信息》 2026年第1期157-166,共10页
本文系统评估了北斗三号(BDS-3)MEO卫星B1C/B2a信号在单系统模式下的精密产品性能,从产品生成与应用两个层面,对比分析了BDS-3 MEO单系统与BDS-3MEO/GPS双系统的表现。结果显示:在定轨模糊度固定方面,BDS-3 MEO单系统的非差宽巷与窄巷... 本文系统评估了北斗三号(BDS-3)MEO卫星B1C/B2a信号在单系统模式下的精密产品性能,从产品生成与应用两个层面,对比分析了BDS-3 MEO单系统与BDS-3MEO/GPS双系统的表现。结果显示:在定轨模糊度固定方面,BDS-3 MEO单系统的非差宽巷与窄巷固定率分别为97.97%和90.28%,接近双系统水平;单系统轨道的1D RMS为51.2 mm,略低于双系统,而钟差拟合残差平均值为0.14 ns,序列平滑性优于双系统;在地球自转参数(ERP)方面,X、Y极坐标的RMS分别为39.2μas和27.8μas,X、Y极坐标速率的RMS分别为230.0μas/d和262.2μas/d,日长变化的RMS为203.2μs/d,部分指标略低于双系统,但整体仍满足精密产品要求;单系统天顶总延迟(ZTD)的平均RMSE为6.7 mm;单系统网解PPP的非差模糊度宽巷固定率超过98%,窄巷平均固定率为83%;静态精密单点定位(PPP)中,单系统收敛时间为27.89 min,E、N、U三个方向的精度分别为1.71 cm、2.34 cm和1.25 cm;在框架一致性比对中,单系统的平均尺度变化为0.065 ppb,优于双系统的0.188 ppb,表明在BDS天线对齐至ITRF 2020后单系统产品框架一致性表现良好。研究证实,BDS-3单系统具备独立生成高精度产品的能力,为北斗系统实现自主运行提供了有力支撑。 展开更多
关键词 北斗三号 MEO b1c/b2a 单系统性能评估
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C2B2C二手电商平台物流模式及发展策略研究
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作者 杨琳 刘嘉豪 盛继丹 《中国储运》 2026年第3期156-157,共2页
在互联网技术演进与消费者行为变迁的驱动下,中国二手电商市场空前繁荣。C2B2C模式作为二手电商平台的一种创新形态,通过深度介入交易流程,实现了二手商品的标准化处理,有效提升了交易效率,但同时也使得平台企业面临负重前行的困境,高... 在互联网技术演进与消费者行为变迁的驱动下,中国二手电商市场空前繁荣。C2B2C模式作为二手电商平台的一种创新形态,通过深度介入交易流程,实现了二手商品的标准化处理,有效提升了交易效率,但同时也使得平台企业面临负重前行的困境,高度依赖于商品物流的稳定性。本文基于当前C2B2C二手电商平台的运营态势及其物流网络结构,揭示平台企业物流网络模式面临的挑战与需求,提出C2B2C二手电商物流优化策略,以期为平台企业提供有益参考。 展开更多
关键词 发展策略 二手电商平台 c2b2c模式 物流模式
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三种不同HIV HBV HCV筛查方法在MSM中的应用评价
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作者 袁宏香 王宇 +6 位作者 李琪 齐玫 高琳琦 郭翔宇 刘畅 金聪 冯霞 《中国艾滋病性病》 北大核心 2026年第2期133-137,共5页
目的 探讨胶体金法、ELISA法及核酸三联检在MSM中HIV、HBV和HCV感染联合筛查中的应用价值。方法 以2024年5-8月在北京佑安医院招募的MSM为研究对象,采用胶体金法、ELISA及核酸三联检法分别检测HIV/HBV/HCV的抗体或核酸,三种方法检测结... 目的 探讨胶体金法、ELISA法及核酸三联检在MSM中HIV、HBV和HCV感染联合筛查中的应用价值。方法 以2024年5-8月在北京佑安医院招募的MSM为研究对象,采用胶体金法、ELISA及核酸三联检法分别检测HIV/HBV/HCV的抗体或核酸,三种方法检测结果不一致的标本进一步做单项核酸定量检测,以个体感染诊断结果为标准,计算并比较三种方法的灵敏度、特异度。结果 400例研究对象中,HIV检测中,三种方法阳性检出数均为23例,且与金标准结果完全一致,符合率达100.00%;HBV检测中,胶体金法灵敏度为63.64%,ELISA法与核酸三联检法灵敏度均为100.00%,两两比较差异无统计学意义(校正后P>0.017);胶体金法特异度为100.00%,显著高于核酸三联检法的97.69%,差异有统计学意义(χ^(2)=9.00,df=1,P=0.003),ELISA法特异度为98.72%,与其余两种方法比较差异均无统计学意义;HCV检测中,胶体金法、ELISA法和核酸三联检阳性检测数分别为2例、4例和2例,且核酸三联检检出的阳性病例为现症感染。结论 胶体金法快速便捷,存在漏检可能;ELISA法适用于大样本筛查,但操作复杂、耗时长;HIV/HBV/HCV核酸三联检与HIV、HCV单项核酸定量检测结果高度一致,更易发现HBV隐匿性感染病例,可成为MSM人群HIV、HBV、HCV多病同检的优选方法。 展开更多
关键词 男男性行为者 艾滋病病毒 乙型肝炎病毒 丙型肝炎病毒 核酸三联检 胶体金法 酶联免疫吸附实验
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Hexagonal B-C-N composite consisting of h-BN and graphite separated by B-C nanolayer
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作者 Baoyin Xu Xiaohong Yuan +10 位作者 Bingtao Feng Yifeng Jiang Yaqi She Zhanhui Ding Yue Pan Shucheng Liu Kuo Hu Zhaodong Liu Quanjun Li Bingbing Liu Hu Tang 《Matter and Radiation at Extremes》 2026年第2期85-94,共10页
Graphite and hexagonal boron nitride(h-BN),despite their structural similarity,exhibit opposing electronic properties,namely,metallic conductivity and wide-bandgap insulation,respectively.In recent years,graphene-h-BN... Graphite and hexagonal boron nitride(h-BN),despite their structural similarity,exhibit opposing electronic properties,namely,metallic conductivity and wide-bandgap insulation,respectively.In recent years,graphene-h-BN heterostructures have attracted significant research interest,with the resulting hybrid B-C-N atomic-layer systems exhibiting distinctive electronic properties.Notably,interface effects play a decisive role in governing the performance of these heterostructures.Nevertheless,owing to the lack of high-quality composites,the interfacial structure in B-C-N materials and the correlation with critical properties such as charge transport and band structure modulation are not fully clear.Here,we report the direct synthesis of a millimeter-sized hexagonal B-C-N composite via a solvent method under high-pressure and high-temperature conditions.Structural characterization reveals that the synthesized B-C-N composite contains isolated graphite and h-BN.Compared with pure h-BN,the B-C-N composite has a narrower bandgap and shows a pronounced photoelectric response in the visible light region.More interestingly,we find a graphite-like B-C compound with a thickness of about 30 nm at the graphite-h-BN interface,which forms Schottky junctions with graphite,thus realizing rectification properties.Our findings provide a method for synthesizing highquality B-C-N composites and offer new insights into the structure of the graphite-h-BN interface. 展开更多
关键词 GRAPHITE photoelectric response electronic propertiesnotablyinterface effects high pressure high temperature synthesis hexagonal boron nitride interface effects hexagonal b c n composite Schottky junction
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Study on FeCl_(3)-Mediated Reaction of Aryl Boronic Esters with Electrophiles
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作者 Cui Lihua Li Yatong Wang Qifeng 《有机化学》 北大核心 2026年第1期199-206,共8页
A concise approach to the synthesis of organoiron intermediate from organoboron and Fe(III)has been developed,and the reactivity of the intermediate with a series of electrophiles has been investigated.The results rev... A concise approach to the synthesis of organoiron intermediate from organoboron and Fe(III)has been developed,and the reactivity of the intermediate with a series of electrophiles has been investigated.The results revealed that pinacol substituent of organoboron is crucial for C—B cleavage.The resulted organoiron intermediate is not stable,with weak nucleophicility.The coupling reactions of organoiron intermediate with acyl chlorides,anhydrides,isocyanates have been performed. 展开更多
关键词 ORGANOIRON ORGANObORON coupling c-b cleavage
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元素掺杂及分子吸附对B4C3电子性质的影响
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作者 李萱 邵立 +2 位作者 门彩瑞 何渊淘 李艳 《吉林大学学报(理学版)》 北大核心 2026年第1期158-165,共8页
研究S,N,P,Si 4种原子掺杂和NO,NO_(2),NH_(3),CO,CO_(2),SO_(2),H_(2)S 7种小分子吸附对B_(4)C_(3)二维材料几何结构和电子性质的影响.结果表明,与本征B_(4)C_(3)材料2.020 eV带隙相比,掺杂和小分子吸附体系的禁带宽度均减小.其中,N掺... 研究S,N,P,Si 4种原子掺杂和NO,NO_(2),NH_(3),CO,CO_(2),SO_(2),H_(2)S 7种小分子吸附对B_(4)C_(3)二维材料几何结构和电子性质的影响.结果表明,与本征B_(4)C_(3)材料2.020 eV带隙相比,掺杂和小分子吸附体系的禁带宽度均减小.其中,N掺杂体系的带隙值在4种体系中最小,因此掺杂N原子对B_(4)C_(3)的电子性质影响最明显. NO_(2)吸附后B_(4)C_(3)由半导体变为金属,表明B_(4)C_(3)可有效检测NO_(2)气体. 展开更多
关键词 密度泛函理论 二维b4c3 掺杂 吸附
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超高温淬火对新型Fe-Cr-B-C合金硬度、冲击韧性和耐磨性能的影响
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作者 韩思莹 赵广迪 +5 位作者 于镇铭 杜磊 王茜雯心 于江铖 王楚今 周艳文 《材料热处理学报》 北大核心 2026年第1期96-107,共12页
Fe-Cr-B-C合金是一种低成本的高硼铁基耐磨合金,具有广阔的应用前景。研究了超高温淬火对一种成分优化的(B含量为0.51 mass%)Fe-Cr-B-C合金显微组织、硬度、冲击韧性和耐磨性能的影响。结果表明:当淬火温度为1100℃,合金基体内析出大量... Fe-Cr-B-C合金是一种低成本的高硼铁基耐磨合金,具有广阔的应用前景。研究了超高温淬火对一种成分优化的(B含量为0.51 mass%)Fe-Cr-B-C合金显微组织、硬度、冲击韧性和耐磨性能的影响。结果表明:当淬火温度为1100℃,合金基体内析出大量二次硼碳化物,降低了马氏体的过饱和度,同时形成了细小的新晶粒,原始网状硼碳化物发生局部断网,这导致其洛氏硬度最低,冲击吸收能量较高,耐磨性能最差;随着淬火温度升高至1160℃,不再析出二次硼碳化物,也不再形成新晶粒,硼碳化物的断网现象更加明显,而马氏体过饱和度不断增大,这导致洛氏硬度增大至(63.2±0.8) HRC,耐磨性能提高;当淬火温度继续升高至1190℃时,重新析出了大量[γ+(Fe, Cr)_(2)(B, C)]共晶组织并形成网状结构,导致洛氏硬度小幅下降,冲击韧性恶化,耐磨性能明显下降;合金的冲击吸收能量随淬火温度的升高先增大后减小,当淬火温度为1130℃时达到最大,为(4.25±0.25) J;综合来看,经1160℃淬火后Fe-Cr-B-C合金获得了良好的强韧性匹配和优异的耐磨性能,可作为其优选淬火温度。 展开更多
关键词 Fe-cr-b-c合金 超高温淬火 硬度 冲击韧性 耐磨性
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蛋白激酶C-B在肺腺癌患者中的表达及临床意义
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作者 陈金金 刘顺林 《全科医学临床与教育》 2026年第3期210-213,F0002,共5页
目的探讨蛋白激酶C-B(PRKCB)在肺腺癌患者中的表达及临床意义。方法选取128例肺腺癌患者为研究对象,所有患者术前均未接受放化疗。采用免疫组化法检测PRKCB蛋白表达,RT-PCR与Western Blot技术检测肺腺癌组织及对应正常肺组织中PRKCB mRN... 目的探讨蛋白激酶C-B(PRKCB)在肺腺癌患者中的表达及临床意义。方法选取128例肺腺癌患者为研究对象,所有患者术前均未接受放化疗。采用免疫组化法检测PRKCB蛋白表达,RT-PCR与Western Blot技术检测肺腺癌组织及对应正常肺组织中PRKCB mRNA与蛋白表达水平。分析PRKCB表达与临床病理参数的相关性,并对患者进行随访,采用Kaplan-Meier法计算生存率,COX回归模型分析预后影响因素。结果128例肺腺癌组织中,PRKCB高表达49例(38.28%),低表达79例(61.72%)。PRKCB蛋白表达与肺腺癌TNM分期、临床分期、淋巴结转移及远处转移明显相关(χ^(2)分别=20.64、8.65、8.09、3.98,P均<0.05)。肺腺癌组织中PRKCB mRNA表达量和PRKCB蛋白表达量均明显低于正常组织,差异均有统计学意义(t分别=10.52、12.34,P均<0.05)。Kaplan-Meier生存分析显示,PRKCB低表达组5年总生存率明显低于高表达组(χ^(2)=18.67,P<0.05)。单因素COX分析显示,肿瘤直径、TNM分期及PRKCB表达均是影响患者预后的危险因素(HR分别=1.44、2.80、4.87,P均<0.05),多因素COX回归分析进一步显示,肿瘤直径、TNM分期及PRKCB表达均为肺腺癌患者预后的独立影响因素(HR分别=1.13、2.21、2.22,P均<0.05)。结论在肺腺癌组织中的PRKCB蛋白表达较正常组织低,且与临床分期、淋巴结转移相关,低表达PRKCB可能是NSCLC预后不良的因素。 展开更多
关键词 蛋白激酶c-b 肺腺癌 免疫组化 逆转录-聚合酶联反应 蛋白印记法
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CyclinD1/c-Myc共表达与弥漫性大B细胞淋巴瘤分子分型及预后的关系
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作者 巩楠 张琰 +3 位作者 黄晶 庞雪莲 骆婷婷 张洋 《疑难病杂志》 2026年第4期395-400,共6页
目的探讨细胞周期蛋白D1(CyclinD1)/c-Myc共表达与弥漫性大B细胞淋巴瘤(DLBCL)分子分型及预后的关系。方法回顾性选取2021年1月一2023年1月新疆医科大学第一附属医院血液病科收治的DLBCL患者102例,随访2年记录患者无进展生存期,并将其... 目的探讨细胞周期蛋白D1(CyclinD1)/c-Myc共表达与弥漫性大B细胞淋巴瘤(DLBCL)分子分型及预后的关系。方法回顾性选取2021年1月一2023年1月新疆医科大学第一附属医院血液病科收治的DLBCL患者102例,随访2年记录患者无进展生存期,并将其分为预后不良组29例和预后良好组73例。采用免疫组织化学法检测DLBCL淋巴结组织中CyclinD1、c-Myc表达;统计CyclinD1/c-Myc共表达患者,采用卡方检验Phi系数分析CyclinD1/c-Myc共表达患者与DLBCL分子分型的关系;Kaplan-Meier曲线和Cox回归分析影响DLBCL患者预后的因素。结果DLBCL患者102例中CyclinD1阳性表达32例(31.37%),c-Myc阳性表达45例(44.12%),Cyclin D1/c-Myc共表达21例(20.59%);非生发中心B细胞样(GCB)亚型的DLBCL患者CyclinD1/c-Myc共表达占比明显高于GCB亚型(28.33%vs.9.52%,X^(2)/P=5.346/0.021);卡方检验Phi系数结果显示,CyclinD1/c-Myc共表达与DLBCL分子分型呈负相关(Phi系数/P=-0.229/0.021);CyclinD1/c-Myc共表达患者生存时间明显短于CyclinD1/c-Myc非共表达患者(Log-RankX^(2)=10.207,P<0.001);预后不良组国际预后指数(IPI)评分、非GCB亚型占比、CyclinD1/c-Myc共表达占比均高于预后良好组(t/P=6.015/<0.001,X^(2)/P=7.021/0.008、24.027/<0.001);IPI评分高、非GCB亚型、CyclinD1/c-Myc共表达是DLBCL患者预后不良的独立危险因素[HR(95%CI)=2.052(1.333~3.158)、2.969(1.197~7.363)、2.880(1.240~6.690)]。结论CyclinD1/c-Myc共表达与DLBCL分子分型及预后均具有一定关系,且Cyclin D1/c-Myc共表达、非GCB亚型是DLBCL患者预后不良的危险因素。 展开更多
关键词 弥漫性大b细胞淋巴瘤 细胞周期蛋白D1 c-MYc 分子分型 预后
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“T-Q-B-C-A-B-I”模型:农产品全产业链协同与农户参与——基于乡村振兴背景下对保定、邢台、唐山三市的调查
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作者 韩佳林 程浩哲 +1 位作者 安昕 王婧瑶 《现代农业研究》 2026年第3期19-32,共14页
在乡村振兴战略推动下,特色农产品全产业链协同与农户深度参与成为产业升级核心,但北方地区相关产业面临技术转化不畅、品质管控松散等问题,现有研究存在协同与参与割裂、量化不足等缺口。本研究旨在构建适配模型,破解产业升级瓶颈。以... 在乡村振兴战略推动下,特色农产品全产业链协同与农户深度参与成为产业升级核心,但北方地区相关产业面临技术转化不畅、品质管控松散等问题,现有研究存在协同与参与割裂、量化不足等缺口。本研究旨在构建适配模型,破解产业升级瓶颈。以保定、邢台、唐山三市为对象,通过问卷调查(852份有效问卷)、实地访谈及官方数据收集,运用AHP层次分析法与多元线性回归,构建“T-Q-B-C-A-B-I”整合模型,即“Technology-Quality-Brand”closed-loop collaborative(“技术-品质-品牌”全产业链闭环协同)模型与Farmers’Participation“Cognition-Ability-Behavior-Income”chain(农户参与“认知-能力-行为-收益”链式)模型。研究发现,该模型具备科学有效性,可揭示全产业链与农户参与的双向关联;北方特色农产品产业在技术、品质、品牌、主体联动方面存在突出短板,农户参与传导路径不畅且呈异质性,二者形成双向制约。研究结果为北方特色农产品产业的高质量发展与乡村振兴提供理论支撑与实践参考。 展开更多
关键词 “T-Q-b-c-A-b-I”整合模型 特色农产品 全产业链 协同路径 农户参与 乡村振兴
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TSH、ApoA/ApoB及CRP与慢性阻塞性肺疾病并发静脉血栓栓塞症的相关性研究
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作者 韩盼盼 彭威 曾曼 《临床研究》 2026年第2期147-150,共4页
目的观察促甲状腺激素(TSH)、载脂蛋白A(ApoA)/载脂蛋白B(ApoB)及C反应蛋白(CRP)与慢性阻塞性肺疾病(COPD)并发静脉血栓栓塞症(VTE)的相关性。方法采用回顾性研究方法,选择2018年3月至2023年3月虞城县人民医院收治的COPD并发VTE患者100... 目的观察促甲状腺激素(TSH)、载脂蛋白A(ApoA)/载脂蛋白B(ApoB)及C反应蛋白(CRP)与慢性阻塞性肺疾病(COPD)并发静脉血栓栓塞症(VTE)的相关性。方法采用回顾性研究方法,选择2018年3月至2023年3月虞城县人民医院收治的COPD并发VTE患者100例为观察组,同期未发生VTE的COPD患者108例为对照组。比较两组实验室指标[D-二聚体、CRP、ApoA/ApoB、降钙素原(PCT)、血尿素氮、血肌酐、白蛋白]、甲状腺功能指标[促甲状腺激素(TSH)、三碘甲状腺原氨酸(T_(3))、游离三碘甲状腺原氨酸(FT_(3))、甲状腺素(T_(4))、游离甲状腺素(FT_(4))]、动脉血气指标[动脉血二氧化碳分压(PaCO_(2))、动脉血氧分压(PaO_(2))],采用二元Logistic回归分析COPD并发VTE的相关因素。结果观察组D-二聚体、CRP水平及PaCO_(2)高于对照组,ApoA/ApoB比值、PaO_(2)及TSH、T_(3)、FT_(3)水平低于对照组,差异有统计学意义(P<0.05)。二元Logistic回归分析结果显示,D-二聚体、CRP和PaCO_(2)水平的升高是COPD并发VTE的独立危险因素(P<0.05);而ApoA/ApoB比值、TSH、T_(3)、FT_(3)和PaO_(2)水平的升高是保护因素(P<0.05)。结论COPD并发VTE患者表现出TSH水平和ApoA/ApoB比值降低、CRP水平升高的特征性改变,这些改变与COPD并发VTE密切相关。 展开更多
关键词 慢性阻塞性肺疾病 静脉血栓栓塞症 促甲状腺激素 载脂蛋白A/载脂蛋白b c反应蛋白 相关性
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B2B2C模式下企业采购EAP服务的决策机制与营销策略
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作者 尚静 《物流科技》 2026年第2期33-36,共4页
研究聚焦B2B2C商业模式下企业采购EAP服务的决策机制与营销策略这一新兴研究领域。基于决策理论与服务营销理论,构建了“需求-决策-营销”整合分析框架,系统考察了EAP服务采购的全过程。研究发现:企业采购决策呈现多维度特征,经济与非... 研究聚焦B2B2C商业模式下企业采购EAP服务的决策机制与营销策略这一新兴研究领域。基于决策理论与服务营销理论,构建了“需求-决策-营销”整合分析框架,系统考察了EAP服务采购的全过程。研究发现:企业采购决策呈现多维度特征,经济与非经济因素共同影响采购行为,且决策过程中存在显著的信息不对称问题;在营销策略方面,EAP服务提供商需实施精准市场细分、定制化价值传递以及多渠道整合传播的三维策略体系。 展开更多
关键词 b2b2c模式 EAP 决策机制 营销策略
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洗化行业智能仓库B2B与B2C一体化方案探讨
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作者 白华清 《物流技术与应用》 2026年第1期105-111,共7页
随着洗化行业的快速发展和电商模式的深入变革,传统的仓储物流体系已无难以满足企业面对B2B与B2C混合业务模式时对效率、精度与成本的高要求。本文旨在探讨智能化立体仓库与多穿库在洗化行业B2B与B2C一体化业务模式中的解决方案与实际... 随着洗化行业的快速发展和电商模式的深入变革,传统的仓储物流体系已无难以满足企业面对B2B与B2C混合业务模式时对效率、精度与成本的高要求。本文旨在探讨智能化立体仓库与多穿库在洗化行业B2B与B2C一体化业务模式中的解决方案与实际应用。本文从洗化行业背景及核心痛点入手,详细阐述适应B2B与B2C混合业务的智能化立体仓库的总体规划、工艺流程与关键技术应用;剖析例如在实施中面临的库存管理、订单处理、时效体验等核心难点,并提出了相应的解决方案。研究表明,构建以自动化立体库、仓库管理系统(WMS)、仓库控制系统(WCS)为核心的技术架构,实现库存一体化管理与作业流程的智能化调度,是洗化企业实现降本增效,并提升供应链核心竞争力的关键路径。 展开更多
关键词 智能化立体仓库 洗化行业 b2bb2c 库存一体化 订单处理 电子标签 可移动式播种墙
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DAAs治疗HCV感染发生HBV再激活的风险:系统评价及Meta分析
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作者 陈莹 陈君 +5 位作者 钟韵 成苇婷 刘泽颖 杨雪瑶 李雪璇 黄泽炳 《中国感染控制杂志》 北大核心 2026年第1期32-46,共15页
目的比较接受直接抗病毒药物(DAAs)治疗的丙型肝炎病毒(HCV)感染患者乙型肝炎病毒(HBV)再激活风险,并评估抗HBV治疗预防HBV再激活的有效性。方法计算机检索中国知网(CNKI)、万方数据库、PubMed、Embase、Cochrane Library数据库,纳入自... 目的比较接受直接抗病毒药物(DAAs)治疗的丙型肝炎病毒(HCV)感染患者乙型肝炎病毒(HBV)再激活风险,并评估抗HBV治疗预防HBV再激活的有效性。方法计算机检索中国知网(CNKI)、万方数据库、PubMed、Embase、Cochrane Library数据库,纳入自建库至2025年2月13日发表的相关文献。按预设纳入与排除标准筛选文献,提取资料并评估质量。采用Revman 5.4和Stata 18.0软件进行Meta分析,并开展敏感性分析和发表偏倚评估。结果共纳入32篇文献,包括31篇队列研究和1篇随机对照研究。涉及21530例HCV感染患者。27项研究报告HCV感染合并HBsAg阳性患者DAAs治疗后的合并HBV再激活发生率为30%(95%CI:16%~45%),24项研究报告HCV感染合并HBsAg阴性、HBcAb阳性患者合并HBV再激活率为0,各研究报道的再激活发生率范围为0~15%。选取14篇文献比较HCV感染合并HBsAg阳性与HCV感染合并HBsAg阴性、HBcAb阳性患者DAAs治疗后HBV再激活的风险,相对危险度(RR)=31.06(95%CI:17.98~53.65)。HCV感染合并HBsAg阳性患者中,HBV DNA<检测下限(LLOQ)组与HBV DNA≥LLOQ组的HBV再激活风险差异无统计学意义(RR=0.75,95%CI:0.52~1.06)。HCV感染合并HBsAg阳性患者中,DAAs治疗同时使用核苷(酸)类似物(NAs)进行预防性抗HBV治疗者,其HBV再激活风险仅为对照组的19%(RR=0.19,95%CI:0.06~0.58)。结论HCV感染合并HBsAg阳性患者接受DAAs治疗后HBV再激活发生率较高;HCV感染合并HBsAg阴性、HBcAb阳性患者接受DAAs治疗后基于现有数据合并HBV再激活发生率估计值为0,但仍存在个别再激活报告,风险并未完全排除。使用NAs预防性抗HBV治疗可降低HCV感染合并HBsAg阳性患者DAAs治疗的HBV再激活风险。对HCV感染患者实施预防性抗HBV治疗和持续管理,有助于提高DAAs治疗的安全性并优化整体疗效。 展开更多
关键词 丙型肝炎病毒 直接抗病毒药物 乙型肝炎病毒再激活
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