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Factors determining changes in the network of marked hiking trails in the Sudetes
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作者 Krzysztof KOŁODZIEJCZYK 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1075-1099,共25页
Hiking trails are a basic type of tourist infrastructure,which,on the one hand,make areas available for tourist traffic,and on the other hand,can contribute to the protection of the natural environment(if they are wel... Hiking trails are a basic type of tourist infrastructure,which,on the one hand,make areas available for tourist traffic,and on the other hand,can contribute to the protection of the natural environment(if they are well designed and maintained).Owing to the variety of performed functions,their designation is determined by several factors:natural,technical,economic,social.Networks of trails change constantly.The aim of this article is to determine exactly what factors influence transformations within the hiking trail networks and what is their significance.To this end,three study areas in the Sudetes were analysed:one on the Polish side of the Sudetes-the Table(Stołowe)Mountains,and two on the Czech side-the rock town near the village of Sloup vČechách and the central part of Zlatohorskávrchovina.An analysis of changes in the shape of the networks over time was carried out,as well as surveys of institutions that were responsible for or influenced these transformations.These areas are characterised by a significant level of changes in the trail network.Among the factors influencing these changes,the tourist attractiveness of the area,the resilience of the environment,the intensity of tourism traffic,the environmental transformations associated with it,the history of tourism development and land ownership changes should be considered the most important.At each stage of forming networks,the key factor should be tourists’needs,including the desire to escape the urbanised environment.For this reason,trails should avoid roads with artificial(hard)surfaces and heavy automobile traffic. 展开更多
关键词 Hiking trails trail networks GRAPHS Tourist traffic Sudetes
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Assessment of programmed death-ligand 1 expression in primary tumors and paired lymph node metastases of gastric adenocarcinoma
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作者 Brendha Cação Coimbra Marina Alessandra Pereira +4 位作者 Leonardo Cardili Venancio Avancini Ferreira Alves Evandro Sobroza de Mello Ulysses Ribeiro Jr Marcus Fernando Kodama Pertille Ramos 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期883-893,共11页
BACKGROUND Anti-programmed death-1/programmed death-ligand 1(PD-1/PD-L1)immuno-therapy has demonstrated promising results on gastric cancer(GC).However,PD-L1 can express differently between metastatic sites and primar... BACKGROUND Anti-programmed death-1/programmed death-ligand 1(PD-1/PD-L1)immuno-therapy has demonstrated promising results on gastric cancer(GC).However,PD-L1 can express differently between metastatic sites and primary tumors(PT).AIM To compare PD-L1 status in PT and matched lymph node metastases(LNM)of GC patients and to determine the correlation between the PD-L1 status and clinicopathological characteristics.METHODS We retrospectively reviewed 284 GC patients who underwent D2-gastrectomy.PD-L1 was evaluated by immunohistochemistry(clone SP142)using the com-bined positive score.All PD-L1+PT staged as pN+were also tested for PD-L1 expression in their LNM.PD-L1(-)GC with pN+served as the comparison group.RESULTS Among 284 GC patients included,45 had PD-L1+PT and 24 of them had pN+.For comparison,44 PD-L1(-)cases with pN+were included(sample loss of 4 cases).Of the PD-L1+PT,54.2%(13/24 cases)were also PD-L1+in the LNM.Regarding PD-L1(-)PT,9.1%(4/44)had PD-L1+in the LNM.The agreement between PT and LNM had a kappa value of 0.483.Larger tumor size and moderate/severe peritumoral inflammatory response were associated with PD-L1 positivity in both sites.There was no statistical difference in overall survival for PT and LNM according to the PD-L1 status(P=0.166 and P=0.837,respectively).CONCLUSION Intra-patient heterogeneity in PD-L1 expression was observed between the PT and matched LNM.This disagreement in PD-L1 status may emphasize the importance of considering different tumor sites for analyses to select patients for immunotherapy. 展开更多
关键词 Gastric cancer Lymph node Programmed death ligand 1 Stomach neoplasms IMMUNOHISTOCHEMISTRY METASTASIS
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Proton‑Prompted Ligand Exchange to Achieve High‑Efficiency CsPbI_(3) Quantum Dot Light‑Emitting Diodes
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作者 Yanming Li Ming Deng +2 位作者 Xuanyu Zhang Lei Qian Chaoyu Xiang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期53-62,共10页
CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting diodes.However,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improv... CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting diodes.However,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improvement of device performance.Traditional in-situ ligand replacement and ligand exchange after synthesis were often difficult to control.Here,we proposed a new ligand exchange strategy using a proton-prompted insitu exchange of short 5-aminopentanoic acid ligands with long-chain oleic acid and oleylamine ligands to obtain stable small-size CsPbI_(3)QDs.This exchange strategy maintained the size and morphology of CsPbI_(3)QDs and improved the optical properties and the conductivity of CsPbI_(3)QDs films.As a result,high-efficiency red QD-based light-emitting diodes with an emission wavelength of 645 nm demonstrated a record maximum external quantum efficiency of 24.45%and an operational half-life of 10.79 h. 展开更多
关键词 CsPbI_(3) perovskite quantum dots Light-emitting diodes ligand exchange Proton-prompted in-situ exchange
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Performance of the walking trail making test in older adults with white matter hyperintensities
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作者 Hong-Yi Zhao Zhi-Qiang Zhang +2 位作者 Yong-Hua Huang Hong Li Fang-Yuan Wei 《World Journal of Psychiatry》 SCIE 2024年第1期102-110,共9页
BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments.We hypothes... BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments.We hypothesized that WTMT performance would be altered in older adults with white matter hyperintensities(WMH).AIM To explore the performance in the WTMT in older people with WMH.METHODS In this single-center,observational study,25 elderly WMH patients admitted to our hospital from June 2019 to June 2020 served as the WMH group and 20 participants matched for age,gender,and educational level who were undergoing physical examination in our hospital during the same period served as the control group.The participants completed the WTMT-A and WTMT-B to obtain their gait parameters,including WTMT-A completion time,WTMT-B completion time,speed,step length,cadence,and stance phase percent.White matter lesions were scored according to the Fazekas scale.Multiple neuropsychological assessments were carried out to assess cognitive function.The relationships between WTMT performance and cognition and motion in elderly patients with WMH were analyzed by partial Pearson correlation analysis.RESULTS Patients with WMH performed significantly worse on the choice reaction test(CRT)(0.51±0.09 s vs 0.44±0.06 s,P=0.007),verbal fluency test(VFT,14.2±2.75 vs 16.65±3.54,P=0.012),and digit symbol substitution test(16.00±2.75 vs 18.40±3.27,P=0.010)than participants in the control group.The WMH group also required significantly more time to complete the WTMT-A(93.00±10.76 s vs 70.55±11.28 s,P<0.001)and WTMT-B(109.72±12.26 s vs 82.85±7.90 s,P<0.001).WTMT-A completion time was positively correlated with CRT time(r=0.460,P=0.001),while WTMT-B completion time was negatively correlated with VFT(r=-0.391,P=0.008).On the WTMT-A,only speed was found to statistically differ between the WMH and control groups(0.803±0.096 vs 0.975±0.050 m/s,P<0.001),whereas on the WTMT-B,the WMH group exhibited a significantly lower speed(0.778±0.111 vs 0.970±0.053 m/s,P<0.001)and cadence(82.600±4.140 vs 85.500±5.020 steps/m,P=0.039),as well as a higher stance phase percentage(65.061±1.813%vs 63.513±2.465%,P=0.019)relative to controls.CONCLUSION Older adults with WMH showed obviously poorer WTMT performance.WTMT could be a potential indicator for cognitive and motor deficits in patients with WMH. 展开更多
关键词 White matter hyperintensities Cognitive dysfunction Motor deficits Gait analysis trail making test Small vessel disease
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Comparative Study of the Efficacy of Metal Removal from Contaminated Aqueous Solutions by Solid Bidentate Ligands&Liquid Plant Materials
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作者 Lovell Agwaramgbo Talajai Sardin Christopher Alisa 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第2期45-49,共5页
Heavy metal contaminated water sources pose serious health risks for humans,animals,and plants.Exposure to and ingestion of heavy metals have been associated to liver,kidney,and brain function.Objective:The aim of thi... Heavy metal contaminated water sources pose serious health risks for humans,animals,and plants.Exposure to and ingestion of heavy metals have been associated to liver,kidney,and brain function.Objective:The aim of this research is to comparatively examine the metal removal efficacy of three solid bidentate chemicals and four plant materials.Study Design&Methods:Standard solutions of zinc(II)and lead(II)ions with concentrations of 1,000 ppm were respectively treated with OA(Oxalic Acid),dibasic bidentate ligands(sodium hydrogen phosphate and sodium carbonate).Then,the solutions were placed on a shaker for 15 h,centrifuged,and the supernatant was analyzed using ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectrometry).Results:All the solid bidentate adsorbents were very effective in removing zinc and lead(>90%).However,more lead than zinc was removed across all adsorbents except for lemon where equal percent of zinc and lead(49%)were removed.OA and Na2HPO4 removed about equal amount of lead(>99%).The plant materials(SP(Spinach),bell pepper and GBP(Green Bell Pepper)),respectively and preferentially removed more lead(98.9%,98.3%,81.5%)than zinc(91.7%,46%,46%).Conclusion:Although plant materials have gained attraction for the remediation of heavy metal,however,some bidentate chemical ligands such as OA,sodium carbonate and sodium hydrogen phosphates are even more effective in removing these metals from contaminated water.Furthermore,heavier metals are preferentially removed than lighter metals. 展开更多
关键词 Organic acids OA REMEDIATION CHELATION ligandS heavy metal contamination
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组织蛋白酶B联合TRAIL诱导胃癌BGC-823细胞凋亡中的作用研究
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作者 查道德 涂龙霞 吴文涌 《包头医学院学报》 CAS 2023年第1期4-7,共4页
目的:观察组织蛋白酶B(CTSB)联合TRAIL诱导胃癌BGC-823细胞凋亡的作用。方法:BGC-823细胞传代培养。采用MTT法检测细胞增殖情况,流式细胞仪检测细胞凋亡率以及免疫印迹法(Western blot)检测Cathepsin B蛋白表达。结果:TRAIL对BGC-823细... 目的:观察组织蛋白酶B(CTSB)联合TRAIL诱导胃癌BGC-823细胞凋亡的作用。方法:BGC-823细胞传代培养。采用MTT法检测细胞增殖情况,流式细胞仪检测细胞凋亡率以及免疫印迹法(Western blot)检测Cathepsin B蛋白表达。结果:TRAIL对BGC-823细胞增殖有抑制作用,对细胞凋亡有促进作用(P<0.05);Cathepsin B抑制剂浓度越高,细胞凋亡率越低(P<0.05);Western blot结果表明,Cathepsin B抑制剂浓度越高,Cathepsin B表达越少(P<0.05)。结论:Cathepsin B和TRAIL联合使用有协同诱导胃腺癌BGC-823细胞凋亡作用。 展开更多
关键词 组织蛋白酶B 肿瘤坏死因子 凋亡配体 BGC-823细胞 细胞凋亡
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肝癌组织中TRAIL表达及其与癌细胞增殖、凋亡、耐药的相关性分析
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作者 孙艳 陈莉 +3 位作者 顾春燕 肖静文 肖锋 张海燕 《南通大学学报(医学版)》 2023年第6期526-531,共6页
目的:研究肿瘤坏死因子相关凋亡诱导配体(tumor-necrosis-factor-related apoptosis-inducing ligand, TRAIL蛋白在肝细胞癌(hepatocellular carcinoma, HCC)组织中的表达水平,分析其与临床病理特征及预后的相关性,并探讨TRAIL对HCC细... 目的:研究肿瘤坏死因子相关凋亡诱导配体(tumor-necrosis-factor-related apoptosis-inducing ligand, TRAIL蛋白在肝细胞癌(hepatocellular carcinoma, HCC)组织中的表达水平,分析其与临床病理特征及预后的相关性,并探讨TRAIL对HCC细胞凋亡、增殖及耐药的影响。方法 :利用免疫组织化学法检测186例HCC患者中HCC组织及癌旁肝组织TRAIL、Caspase-3、NF-κB、P-糖蛋白(P-glycoprotein, P-gP)及Ki-67的表达,分析TRAIL与临床病理特征及预后的关系,并探讨TRAIL与HCC生物学行为(增殖、凋亡、耐药)的相关性。结果:HCC组织中TRAIL表达明显低于癌旁肝组织(P<0.01)。HCC中Caspase-3、NF-κB、P-gP的阳性表达率分别为38.2%、84.4%、66.1%,Ki-67在HCC中的高表达率为75.8%,低表达率为24.2%。Spearman相关性分析显示TRAIL与Caspase-3的表达呈正相关(P<0.01),与NF-κB、P-gP、Ki-67的表达均呈负相关(均P<0.05)。Kaplan-Meier生存分析显示,TRAIL阳性表达患者的平均生存时间显著长于阴性表达者(P<0.01)。单因素和Cox模型多因素分析结果显示TRAIL低表达与术后复发是HCC预后的独立影响因素(P<0.05)。结论:TRAIL在HCC中低表达,并与脉管癌栓、肿瘤病理分级、术后复发有关,提示TRAIL低表达是HCC恶性进展中的关键性分子事件。检测TRAIL表达在评价HCC分级、浸润、复发及预后中有一定的价值。 展开更多
关键词 肝细胞癌 肿瘤坏死因子相关凋亡诱导配体 增殖 凋亡 耐药 预后
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Following a TRAIL: Update on a ligand and its five receptors 被引量:27
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作者 Fiona C. KIMBERLEY Gavin R. SCREATON 《Cell Research》 SCIE CAS CSCD 2004年第5期359-372,共14页
Identification of tumour necrosis factor apoptosis inducing ligand (TRAIL), a TNF family ligand, sparked a torrent of research, following an initial observation that it could kill tumour cells, but spare normal cells.... Identification of tumour necrosis factor apoptosis inducing ligand (TRAIL), a TNF family ligand, sparked a torrent of research, following an initial observation that it could kill tumour cells, but spare normal cells. Almost a decade after its discovery, and with five known receptors, the true physiological role of TRAIL is still debated and its anti-tumorigenic properties limited by potential toxicity. This review takes a comprehensive look at the story of this enigmatic ligand, addressing its remaining potential as a therapeutic and providing an overview of the TRAIL receptors themselves. 展开更多
关键词 肿瘤坏死因子细胞凋亡诱导配位子 受体 癌症 细胞凋亡 治疗
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帕博利珠联合紫杉醇激活TRAILR/TRAIL促进食管癌细胞凋亡 被引量:1
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作者 尹宏飞 柴立勋 +1 位作者 王玉璇 杨更朴 《中国免疫学杂志》 CAS CSCD 北大核心 2023年第4期783-786,共4页
目的:初步探索帕博利珠联合紫杉醇促进食管癌细胞凋亡的机制。方法:qRT-PCR和Western blot检测食管癌组织和细胞中TRAILR2表达,以及食管癌细胞中caspase3和caspase8表达。CCK-8检测紫杉醇对食管癌细胞存活的影响。紫杉醇处理食管癌细胞... 目的:初步探索帕博利珠联合紫杉醇促进食管癌细胞凋亡的机制。方法:qRT-PCR和Western blot检测食管癌组织和细胞中TRAILR2表达,以及食管癌细胞中caspase3和caspase8表达。CCK-8检测紫杉醇对食管癌细胞存活的影响。紫杉醇处理食管癌细胞的同时过表达TRAILR2,鉴定紫杉醇对TRAILR/TRAIL途径的激活作用。构建小鼠食管癌异种移植模型,流式细胞术检测帕博利珠和紫杉醇对食管癌细胞凋亡的影响。结果:TRAILR2在食管癌组织和细胞中均正常表达。紫杉醇可有效抑制食管癌细胞存活,并激活TRAILR/TRAIL途径。紫杉醇可诱导食管癌细胞凋亡,而紫杉醇处理的同时过表达TRAILR2,细胞凋亡情况有所恢复。帕博利珠和紫杉醇均能抑制食管癌实体瘤体积和重量,而帕博利珠和紫杉醇联合处理可进一步增强这种抑制作用。流式细胞术结果表明,帕博利珠和紫杉醇联合处理促进食管癌细胞凋亡。结论:帕博利珠联合紫杉醇可通过TRAILR/TRAIL途径促进食管癌细胞凋亡。 展开更多
关键词 帕博利珠 紫杉醇 trailR/trail 食管癌 细胞凋亡
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Unraveling structure and performance of protein a ligands at liquid–solid interfaces: A multi-techniques analysis 被引量:1
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作者 Yi Shen Xinshuang Chu Qinghong Shi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期232-239,共8页
Oriented ligand immobilization is one of the most effective strategies used in the design and construction of a high-capacity protein A chromatography. In this work, cysteine was introduced as anchoring sites by subst... Oriented ligand immobilization is one of the most effective strategies used in the design and construction of a high-capacity protein A chromatography. In this work, cysteine was introduced as anchoring sites by substituting a specific residue on Helix Ⅰ, Ⅱ, and at C-terminus of antibody binding domain Z from protein A, respectively, to investigate structural evolution and binding behavior of protein A ligands at liquid-solid interfaces. Among the three affinity dextran-coated Fe_(3)O_(4) magnetic nanoparticles(Fe_(3)O_(4)@Dx MNPs), affinity MNPs with the immobilized ligand via N11C on Helix Ⅰ(Fe_(3)O_(4)@Dx-Z_(1) MNPs) had the highest helical content, and MNPs with the immobilized ligand via G29C on Helix Ⅱ(Fe_(3)O_(4)@Dx-Z_(2) MNPs) had the lowest helical content at the same pHs. It was attributed to less electrostatic attraction of ligand to negatively charged surface on Fe_(3)O_(4)@Dx-Z_(1) MNPs because of less positive charged residues on Helix Ⅰ(K6) than Helix Ⅱ(R27/K35). Among the three affinity MNPs, moreover, the highest affinity to immunoglobulin G(IgG) binding was observed on Fe_(3)O_(4)@Dx-Z_(1) MNPs in isothermal titration calorimetry measurement, further validating greater structural integrity of the ligand on Fe_(3)O_(4)@Dx-Z_(1) MNPs. Finally,the study of IgG binding on MNPs and 96-well plates showed that anchoring sites for ligand immobilization had distinct influences on IgG binding and IgG-mediated antigen binding. This work illustrated that anchoring sites of the ligands had a striking significance for the molecular structure of the ligand at liquid-solid interfaces and raised an important implication for the design and optimization of protein A chromatography and protein A-based immunoassay analysis. 展开更多
关键词 ADSORPTION Interface THERMODYNAMICS Protein A ligand IMMOBILIZATION Molecular structure
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A fast and in-depth self-reconstruction of anion ligands optimized CoFe-based pre-catalysts for water oxidation 被引量:1
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作者 Qiuyan Jin Hao Cui Chengxin Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期812-819,共8页
The design of efficient and robust non-precious metal electrocatalysts towards oxygen evolution reaction(OER)is of great value for developing green energy technologies.The in-situ formed high-valence(oxy)hydroxides sp... The design of efficient and robust non-precious metal electrocatalysts towards oxygen evolution reaction(OER)is of great value for developing green energy technologies.The in-situ formed high-valence(oxy)hydroxides species during the reconstruction process of pre-catalysts are recognized as the real contributing sites for OER.However,pre-catalysts generally undergo a slow and inadequate self-reconstruction.Herein,we reported a PO^(3-)_(4)optimized CoFe-based OER catalysts with amorphous structure,which enables a fast and deep reconstruction during the OER process.The amorphous structure induced by ligands PO^(3-)_(4)is prone to evolution and further form active species for OER.The electron interaction between metal sites can be modulated by electron-rich PO^(3-)_(4),which promotes generation of high active CoOOH.Simultaneously,the etching of PO^(3-)_(4)from the pre-catalysts during the catalytic process is in favor of accelerating the self-reconstruction.As a result,as-prepared precatalyst can generate high active CoOOH at a low potential of 1.4 V and achieve an in-depth reconstructed nanosheet structure with abundant OER active sites.Our work provides a promising design of pre-catalysts for realizing efficient catalysis of water oxidation. 展开更多
关键词 Oxygen evolution reaction Pre-catalysts Reconstruction Anion ligands Bimetallic catalysts
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TRAIL在HCC治疗研究中的新进展
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作者 黄妮 唐科 陈薇 《华夏医学》 CAS 2023年第5期179-185,共7页
肝细胞癌(HCC)是当今社会最常见的恶性肿瘤之一。手术切除仍是目前主要的治疗方法,但术后存在死亡率高、预后差等问题,因此寻求更加安全、高效的治疗策略尤为重要。肿瘤坏死因子相关凋亡诱导配体(TRAIL)是肿瘤坏死因子(TNF)家族的新成... 肝细胞癌(HCC)是当今社会最常见的恶性肿瘤之一。手术切除仍是目前主要的治疗方法,但术后存在死亡率高、预后差等问题,因此寻求更加安全、高效的治疗策略尤为重要。肿瘤坏死因子相关凋亡诱导配体(TRAIL)是肿瘤坏死因子(TNF)家族的新成员之一,相关受体在治疗肿瘤方面具有良好的优势,是具有抗肿瘤作用的潜在靶点。近年来,基于TRAIL受体激动剂及其联合治疗策略已经投入临床HCC的治疗,并取得了不错的临床治疗预期。但随着HCC耐药的发展,针对现有机制的TRAIL受体激动剂似乎难以达到预期效果,因此深入探寻HCC耐药机制及其新的联合治疗策略,对于HCC治疗十分必要。本文主要对TRAIL在发挥治疗HCC中涉及的相关机制尤其是相关耐药机制以及近年临床上使用的TRAIL受体激动剂联合用药策略进行综述。 展开更多
关键词 trail蛋白 肝细胞癌 耐药性 联合用药
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TRAIL联合顺铂诱导三阴乳腺癌MDA-MB-231细胞过度性自噬的分子机制 被引量:1
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作者 岳子雯 杨彪 +1 位作者 刘皓 周伟强 《中国药理学通报》 CAS CSCD 北大核心 2023年第8期1599-1600,共2页
流行病学报道,乳腺癌成为目前女性发病率和死亡率最高的癌症[1]。而铂类药物也是临床上最常用的周期非特异性抗肿瘤药物,在临床治疗实体肿瘤中显示了良好的疗效[2]。其中顺铂作为一线临床的传统用药,其靶点选择范围窄、疗效差、易耐药... 流行病学报道,乳腺癌成为目前女性发病率和死亡率最高的癌症[1]。而铂类药物也是临床上最常用的周期非特异性抗肿瘤药物,在临床治疗实体肿瘤中显示了良好的疗效[2]。其中顺铂作为一线临床的传统用药,其靶点选择范围窄、疗效差、易耐药等问题,尚未得到解决。肿瘤坏死因子相关凋亡诱导配体(tumor necrosis factor-related apoptosis-inducing ligand,TRAIL)属于肿瘤坏死因子(tumor necrosis factor,TNF)超家族。 展开更多
关键词 顺铂 肿瘤坏死因子相关凋亡诱导配体 三阴乳腺癌 自噬 MDA-MB-231 细胞凋亡
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FEM1B促进TRAIL诱导的HIV潜伏库细胞ACH-2的细胞凋亡
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作者 杨晨波 陆佳涵 +1 位作者 丛喆 薛婧 《中国比较医学杂志》 CAS 北大核心 2023年第5期1-7,共7页
目的探究FEM1B对HIV潜伏库细胞ACH-2的凋亡影响及作用。方法利用慢病毒转染构建FEM1B过表达的ACH-2细胞株,采用FITC-Annexin-V/7-AAD染色检测FEM1B过表达的ACH-2细胞株的细胞自发凋亡以及TRAIL作用24 h后的细胞凋亡情况,以及用qPCR检测T... 目的探究FEM1B对HIV潜伏库细胞ACH-2的凋亡影响及作用。方法利用慢病毒转染构建FEM1B过表达的ACH-2细胞株,采用FITC-Annexin-V/7-AAD染色检测FEM1B过表达的ACH-2细胞株的细胞自发凋亡以及TRAIL作用24 h后的细胞凋亡情况,以及用qPCR检测TRAIL作用前后细胞上清病毒载量。结果FEM1B过表达的细胞株的细胞自发凋亡没有显著变化,但在TRAIL作用下,过表达FEM1B的细胞株的凋亡率显著增加,同时FEM1B过表达后TRAIL作用下ACH-2的上清病毒载量明显上升。结论FEM1B能够促进TRAIL作用下HIV潜伏细胞的细胞凋亡和病毒载量。 展开更多
关键词 细胞凋亡 FEM1B trail HIV潜伏库
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Astrometric Reduction of Saturnian Satellites with Cassini-ISS Images Degraded by Trailed Stars
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作者 Qing-Feng Zhang Meng-Qi Liu +4 位作者 Yan Li Lin-Peng Wu Zhi-Qiang Wang Li-Sha Zhu Zhan Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第3期85-92,共8页
The Imaging Science Subsystem(ISS)mounted on the Cassini spacecraft has taken a lot of images,which provides an important source of high-precision astrometry of some planets and satellites.However,some of these images... The Imaging Science Subsystem(ISS)mounted on the Cassini spacecraft has taken a lot of images,which provides an important source of high-precision astrometry of some planets and satellites.However,some of these images are degraded by trailed stars.Previously,these degraded images cannot be used for astrometry.In this paper,a new method is proposed to detect and compute the centers of these trailed stars automatically.The method is then performed on the astrometry of ISS images with trailed stars.Finally,we provided 658 astrometric positions between 2004 and 2017 of several satellites that include Enceladus,Dione,Tethys,Mimas and Rhea.Compared with the JPL ephemeris SAT427,the mean residuals of these measurements are 0.11 km and 0.26 km in R.A.and decl.,respectively.Their standard deviations are 1.08 km and 1.37 km,respectively.The results show that the proposed method performs astrometric measurements of Cassini ISS images with trailed stars effectively. 展开更多
关键词 STARS trail SATURN
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Research Note: A Multi-Method Approach to Monitor Recreational Trail Usage in Complex Spatial Settings
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作者 Sharon A. Jones Alex Junge Ruth Dittrich 《Open Journal of Forestry》 2023年第1期1-12,共12页
Trail use by pedestrians has become more popular in the United States over the last decade although few studies explore the use of technology to monitor high use trails. Monitoring trail users is an important part of ... Trail use by pedestrians has become more popular in the United States over the last decade although few studies explore the use of technology to monitor high use trails. Monitoring trail users is an important part of trail management and an optimal monitoring system usually depends on site-specific characteristics. The objective of this study was to demonstrate how using a multi-methods system to monitor backcountry trail usage in complex spatial settings can be a useful approach for collecting the information that trail managers need. Given the national growth in recreational hiking, we were particularly interested in exploring these issues for highly visited trails close to urban areas and selected a portion of the Larch Trail leading to the top of Multnomah Falls for the study. The multi-methods approach that we used included a combination of automated infrared sensor counts, manual counts, parking lot data from an inductive loop, and travel time estimates collected with low-energy Bluetooth sensors. We found that using multiple methods allowed for a cost-effective and rich data set that considered the site characteristics and the specific need of the trail managers. We expect that many backcountry trail settings have complex landscape and physical design without robust pre-existing baseline data and hope that our insights will aid trail managers as they strive for a sustainable balance between human use and landscape impact. 展开更多
关键词 Visitor Behavior trail Monitoring Pedestrian trails Infrared Sensors
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Engineering of Ag@Pd/Al_(2)O_(3)with varied Pd-shell thickness:Dynamic evolution of ligand and strain effects on acetylene selective hydrogenation
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作者 Mingbo Yang Tianxing Yang +3 位作者 Rui Ma Sha Li Yufei He Dianqing Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期139-148,共10页
Bimetallic nanoparticles exhibit a synergistic effect that critically depends on their surface composition,but such promotion mechanisms become vague with varying surface compositions.Here,alumina supported Ag@Pd core... Bimetallic nanoparticles exhibit a synergistic effect that critically depends on their surface composition,but such promotion mechanisms become vague with varying surface compositions.Here,alumina supported Ag@Pd core–shell and PdAg alloy structure with controlled size and surface compositions were prepared to demonstrate synergetic mechanisms,particularly,ligand and strain effects on activity and ethylene selectivity for acetylene hydrogenation.The performance evaluation indicates that Ag@Pd catalysts with well-controlled Pd-shell thickness can effectively lower apparent activation energy and improve ethylene selectivity.Hydrogenation activity increases from 0.019 to 0.062 s^(-1) with decreasing Pd-shell thickness under mild conditions,which is 3–6 times higher than their alloyed and monometallic counterparts.Combined characterizations and density functional theory are conducted to reveal such shell-thickness-dependent performance.The ligand effect arising from Ag alloying in the interface of Ag@Pd2ML observes the strongest binding of acetylene,but it diminished sharply and the strain effect gets more prevailing with increasing shell thickness.The competition of ethylene desorption and deephydrogenation were also investigated to understand the selectivity governing factors,and the selectivity descriptor(0.5BE(C_(2)H_(4))–BE(H))was built to match the contribution of ligand and strain effect on the different surfaces of Pd-Ag bimetallic NPs.The exploration of synergetic mechanisms among bimetallic NPs with varied structure and surface compositions in this work can help us to deepen the understanding catalyst structure–activity relationship and provide a feasible way to optimize the overall catalytic performance. 展开更多
关键词 Catalyst HYDROGENATION NANOSTRUCTURE Shell-thickness-dependent performance ligand and strain effect
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Ligand Engineering in Tin-Based Perovskite Solar Cells
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作者 Peizhou Li Xiangrong Cao +9 位作者 Jingrui Li Bo Jiao Xun Hou Feng Hao Zhijun Ning Zuqiang Bian Jun Xi Liming Ding Zhaoxin Wu Hua Dong 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期112-150,共39页
Perovskite solar cells(PSCs)have attracted aggressive attention in the photovoltaic field in light of the rapid increasing power conversion efficiency.However,their large-scale application and commercialization are li... Perovskite solar cells(PSCs)have attracted aggressive attention in the photovoltaic field in light of the rapid increasing power conversion efficiency.However,their large-scale application and commercialization are limited by the toxicity issue of lead(Pb).Among all the lead-free perovskites,tin(Sn)-based perovskites have shown potential due to their low toxicity,ideal bandgap structure,high carrier mobility,and long hot carrier lifetime.Great progress of Sn-based PSCs has been realized in recent years,and the certified efficiency has now reached over 14%.Nevertheless,this record still falls far behind the theoretical calculations.This is likely due to the uncontrolled nucleation states and pronounced Sn(Ⅳ)vacancies.With insights into the methodologies resolving both issues,ligand engineering-assisted perovskite film fabrication dictates the state-of-the-art Sn-based PSCs.Herein,we summarize the role of ligand engineering during each state of film fabrication,ranging from the starting precursors to the ending fabricated bulks.The incorporation of ligands to suppress Sn~(2+)oxidation,passivate bulk defects,optimize crystal orientation,and improve stability is discussed,respectively.Finally,the remained challenges and perspectives toward advancing the performance of Sn-based PSCs are presented.We expect this review can draw a clear roadmap to facilitate Sn-based PSCs via ligand engineering. 展开更多
关键词 PEROVSKITE Solar cells LEAD-FREE ligand engineering DEFECTS Stability
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Enhancing performance of inverted quantum-dot light-emitting diodes based on a solution-processed hole transport layer via ligand treatment
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作者 Depeng Li Jingrui Ma +8 位作者 Wenbo Liu Guohong Xiang Xiangwei Qu Siqi Jia Mi Gu Jiahao Wei Pai Liu Kai Wang Xiaowei Sun 《Journal of Semiconductors》 EI CAS CSCD 2023年第9期68-74,共7页
The performance of inverted quantum-dot light-emitting diodes(QLEDs)based on solution-processed hole transport layers(HTLs)has been limited by the solvent-induced damage to the quantum dot(QD)layer during the spin-coa... The performance of inverted quantum-dot light-emitting diodes(QLEDs)based on solution-processed hole transport layers(HTLs)has been limited by the solvent-induced damage to the quantum dot(QD)layer during the spin-coating of the HTL.The lack of compatibility between the HTL’s solvent and the QD layer results in an uneven surface,which negatively impacts the overall device performance.In this work,we develop a novel method to solve this problem by modifying the QD film with 1,8-diaminooctane to improve the resistance of the QD layer for the HTL’s solvent.The uniform QD layer leads the inverted red QLED device to achieve a low turn-on voltage of 1.8 V,a high maximum luminance of 105500 cd/m2,and a remarkable maximum external quantum efficiency of 13.34%.This approach releases the considerable potential of HTL materials selection and offers a promising avenue for the development of high-performance inverted QLEDs. 展开更多
关键词 quantum dots quantum-dot light-emitting diodes inverted structure ligand treatment
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Metal-organic frameworks with mixed-ligands strategy as heterogeneous nucleation center to assist crystallization for efficient and stable perovskite solar cells
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作者 Yayu Dong Shuang Gai +9 位作者 Jian Zhang Ruiqing Fan Boyuan Hu Wei Wang Wei Cao Jiaqi Wang Ke Zhu Debin Xia Lin Geng Yulin Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期1-10,I0001,共11页
Deep-level defects and random oriented configuration in perovskite crystallization process would cause the nonradiative recombination and further affect the performance of perovskite solar cells(PSCs).Herein,two metal... Deep-level defects and random oriented configuration in perovskite crystallization process would cause the nonradiative recombination and further affect the performance of perovskite solar cells(PSCs).Herein,two metal-organic frameworks(MOFs)with tunable Lewis-base passivation sites have been constructed(Cd-Httb and Cd-Httb-BDC,Httb=5-(4-(1H-1,2,4-triazole-1-yl)benzyl)-1h-tetrazole,BDC=1,4-dicarboxybenzene)to eliminate deep-level defects and simultaneously as nanostructured heterogeneous nucleation seed to assist the growth of large-grained perovskite films.Compared with the control and Cd-Httb,Cd-Httb-BDC designed with mix-ligands strategy exhibited the enhanced inducted effect on the crystallization and nucleation of high-quality perovskite films during annealing process.Consequently,the resultant Cd-Httb-BDC-modified device achieved higher power conversion efficiency(PCE)(22.18%)than the control(20.89%)and Cd-Httb(21.56%).Meanwhile,the unencapsulated Cd-Httb-BDC-modified device still maintained 90%of initial PCE after 1500 h in ambient conditions and exhibited enhanced thermal stability(85℃ in N_(2) atmosphere).This work presented a successful example of mixligands strategy on construction of high-quality MOF-assisted perovskite films for high-efficient and stable PSCs. 展开更多
关键词 Perovskite solar cells Metal organic frameworks Mixed ligands strategy Passivation Stability
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