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Nursing Care and Causative Analysis of Grade IV Capsular Contracture Following Breast Cancer Expander Implantation
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作者 Rong Chen nan zhang Huiting zhang 《Advances in Breast Cancer Research》 CAS 2024年第1期1-9,共9页
Objective: By observing the treatment and nursing care of a patient with Grade IV capsular contracture following breast cancer expander implantation and subsequent Stage II reconstruction, we aim to analyze the reason... Objective: By observing the treatment and nursing care of a patient with Grade IV capsular contracture following breast cancer expander implantation and subsequent Stage II reconstruction, we aim to analyze the reasons for the formation of capsular contracture after Stage I expander implantation and prevent its recurrence following Stage II reconstruction. Methods: In May 2020, the patient noticed an increase in the size of a breast mass. In August, she underwent AC-THP neoadjuvant chemotherapy, followed by a “right breast-conserving nipple-areolar subglandular excision + right axillary lymph node dissection + expander implantation” surgery in November 2020. Radiation therapy began in January 2021. During radiation therapy, the patient experienced severe breast hardening, distortion, tenderness, and was diagnosed with Grade IV capsular contracture. To relieve the capsular contracture, the patient underwent a “contracted capsule incision and release procedure + removal of the right breast expander + right breast implantation” surgery in July 2021. Postoperatively, measures were taken to prevent incision infection, emphasizing aseptic techniques, ensuring smooth negative pressure drainage, reducing skin flap tension, monitoring skin flap blood supply, actively preventing subcutaneous effusion and hematoma, and applying appropriate compression dressings. Results: The patient was discharged after the removal of the drainage tube. During the postoperative follow-up at 3 and 6 months, there was no recurrence of capsular contracture, and the breast appeared full, upright, and relatively soft. There were no complications such as hematoma, infection, breast implant rupture, breast sagging, or displacement. The patient had a good outcome without additional financial or surgical burdens. Conclusion: The occurrence of Grade IV capsular contracture in the patient is generally related to infection after Stage I expander implantation, improper compression dressing, excessive saline injection causing content infiltration, and radiation therapy. Therefore, it is recommended to enhance the intraoperative and postoperative prophylactic use of antibiotics after Stage I expander implantation. Intermittent saline injection after surgery, with the amount of saline gradually increasing rather than filling all at once, is advisable. This helps the breast tissue gradually adapt to expansion, reducing the risk of capsular contracture. Postoperatively, patients should be instructed to wear pressure garments and breast elastic bandages while intensifying breast monitoring during radiation therapy and increasing postoperative follow-up. 展开更多
关键词 Breast Cancer Capsular Contracture Expander Implantation
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Quantitative Study on Morphological Change Characteristics of Tonle Sap Lake Based on DEM
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作者 Yan Huang Yifei Tian +6 位作者 Changwen Li Wu Liu nan zhang Haiyang Wang Yue Wu Wanting Feng Yifan Yu 《Open Journal of Modern Hydrology》 CAS 2024年第1期1-13,共13页
Lake is an important part of the natural ecosystem, and its morphological characteristics reflect the capacity of lake regulation and storage, the strength of material migration, and the characteristics of shoreline d... Lake is an important part of the natural ecosystem, and its morphological characteristics reflect the capacity of lake regulation and storage, the strength of material migration, and the characteristics of shoreline development. In most existing studies, remote sensing images are used to quantify the morphological characteristics of lakes. However, the extraction accuracy of lake water is greatly affected by cloud cover and vegetation cover, and the inversion accuracy of lake elevation data is poor, which cannot accurately describe the response relationship of lake landscape morphology with water level change. Therefore, this paper takes Tonle Sap Lake as the research object, which is the largest natural freshwater lake in Southeast Asia. DEM is constructed based on high-resolution measured topographic data, and morphological indicators such as lake area, lake shoreline length, perimeter area ratio, longest axis length, maximum width, shoreline development index, lake shape complexity, compactness ratio and form ratio are adopted to researching the evolution law of high water overflows and low water outbursts quantitatively, and clarifying the variation characteristics of landscape morphology with water level gradient in Tonle Sap Lake. The research results have important theoretical significance for the scientific utilization of Tonle Sap Lake water resources and the protection of the lake ecosystem. 展开更多
关键词 Tonle Sap Lake DEM Geometrical Morphology Variation Characteristic
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如何实现“黑箱”下的算法治理?——平台推荐算法监管的测量实验与策略探索
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作者 张楠 闫涛 张腾 《公共行政评论》 北大核心 2024年第1期25-44,M0003,共21页
近年来,平台推荐算法的快速发展和广泛应用深刻改变了互联网信息内容的供给方式,同时也引发了一系列算法风险与现实问题。平台推荐算法治理与监管成为政府规范算法应用的重点内容之一,无论是算法备案制度的探索,还是实现算法透明化的设... 近年来,平台推荐算法的快速发展和广泛应用深刻改变了互联网信息内容的供给方式,同时也引发了一系列算法风险与现实问题。平台推荐算法治理与监管成为政府规范算法应用的重点内容之一,无论是算法备案制度的探索,还是实现算法透明化的设想,均面临着一定的困难和挑战。在不打开算法“黑箱”的前提下,平台推荐算法规制与监管是否有可行之道?论文基于机器行为学思想,采用实验方法,以用户视角对推荐结果进行跟踪记录,通过实验数据的对比分析,验证了平台推荐算法结果差异的可测性。基于实验结果,论文提出了通过对不同平台推荐结果进行大规模数据测试和检验,测量平台推荐算法运行逻辑与推荐效果,从而实现“黑箱”下有效的逆向监管,以期丰富未来算法治理的选择。 展开更多
关键词 推荐算法 算法治理 算法监管 机器行为学
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云南6个特有少数民族成人维生素D营养状况分析
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作者 张楠 杨彦玲 +5 位作者 万青青 赵江 彭敏 朱晓 刘志涛 张强 《昆明医科大学学报》 CAS 2024年第2期105-111,共7页
目的分析云南6个特有少数民族成人维生素D营养状况及相关因素。方法2019年5月至2020年8月,在基诺族、布朗族、景颇族、德昂族、阿昌族和普米族聚居地按照第六次全国人口普查的年龄和性别构成共抽取690名成人。由经过培训的调查员进行问... 目的分析云南6个特有少数民族成人维生素D营养状况及相关因素。方法2019年5月至2020年8月,在基诺族、布朗族、景颇族、德昂族、阿昌族和普米族聚居地按照第六次全国人口普查的年龄和性别构成共抽取690名成人。由经过培训的调查员进行问卷调查和体格测量,并采用液相色谱串联质谱法检测血清25羟维生素D[25(OH)D]。结果调查对象血清25(OH)D中位数为28.7(P25~P75∶24.3~33.8)ng/mL;维生素D充足、不足和缺乏的比例分别为44.2%、47.5%和8.3%。各民族成人血清维生素D水平差异存在统计学意义(χ^(2)=139.29,P<0.01)。多因素Logistic回归分析显示,居住地纬度相对较高的普米族、景颇族、德昂族和阿昌族,女性以及超重肥胖者更易出现维生素D不足或缺乏。结论超过一半的云南特有少数民族成人面临着维生素D营养不良的问题,且各民族间存在差异,应进一步加强对重点地区和人群的监测和干预。 展开更多
关键词 维生素D 少数民族 成年人 营养状况
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Artificial intelligence-assisted repair of peripheral nerve injury: a new research hotspot and associated challenges
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作者 Yang Guo Liying Sun +3 位作者 Wenyao Zhong nan zhang Zongxuan Zhao Wen Tian 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期663-670,共8页
Artificial intelligence can be indirectly applied to the repair of peripheral nerve injury.Specifically,it can be used to analyze and process data regarding peripheral nerve injury and repair,while study findings on p... Artificial intelligence can be indirectly applied to the repair of peripheral nerve injury.Specifically,it can be used to analyze and process data regarding peripheral nerve injury and repair,while study findings on peripheral nerve injury and repair can provide valuable data to enrich artificial intelligence algorithms.To investigate advances in the use of artificial intelligence in the diagnosis,rehabilitation,and scientific examination of peripheral nerve injury,we used CiteSpace and VOSviewer software to analyze the relevant literature included in the Web of Science from 1994–2023.We identified the following research hotspots in peripheral nerve injury and repair:(1)diagnosis,classification,and prognostic assessment of peripheral nerve injury using neuroimaging and artificial intelligence techniques,such as corneal confocal microscopy and coherent anti-Stokes Raman spectroscopy;(2)motion control and rehabilitation following peripheral nerve injury using artificial neural networks and machine learning algorithms,such as wearable devices and assisted wheelchair systems;(3)improving the accuracy and effectiveness of peripheral nerve electrical stimulation therapy using artificial intelligence techniques combined with deep learning,such as implantable peripheral nerve interfaces;(4)the application of artificial intelligence technology to brain-machine interfaces for disabled patients and those with reduced mobility,enabling them to control devices such as networked hand prostheses;(5)artificial intelligence robots that can replace doctors in certain procedures during surgery or rehabilitation,thereby reducing surgical risk and complications,and facilitating postoperative recovery.Although artificial intelligence has shown many benefits and potential applications in peripheral nerve injury and repair,there are some limitations to this technology,such as the consequences of missing or imbalanced data,low data accuracy and reproducibility,and ethical issues(e.g.,privacy,data security,research transparency).Future research should address the issue of data collection,as large-scale,high-quality clinical datasets are required to establish effective artificial intelligence models.Multimodal data processing is also necessary,along with interdisciplinary collaboration,medical-industrial integration,and multicenter,large-sample clinical studies. 展开更多
关键词 artificial intelligence artificial prosthesis medical-industrial integration brain-machine interface deep learning machine learning networked hand prosthesis neural interface neural network neural regeneration peripheral nerve
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d-d Orbital coupling induced by crystal-phase engineering assists acetonitrile electroreduction to ethylamine
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作者 Honggang Huang Yao Chen +7 位作者 Hui Fu Cun Chen Hanjun Li Zhe zhang Feili Lai Shuxing Bai nan zhang Tianxi Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期216-225,I0006,共11页
The d-d orbital coupling induced by crystal-phase engineering can effectively adjust the electronic structure of electrocatalysts,thus showing significant catalytic performance,while it has been rarely explored in ele... The d-d orbital coupling induced by crystal-phase engineering can effectively adjust the electronic structure of electrocatalysts,thus showing significant catalytic performance,while it has been rarely explored in electrochemical acetonitrile reduction reaction(ARR)to date.Herein,we successfully realize the structural transformation of Pd Cu metallic aerogels(MAs)from face-centered cubic(FCC)to body-centered cubic(BCC)through annealing treatment.Specifically,the BCC Pd Cu MAs exhibit excellent ARR performance with high ethylamine selectivity of 90.91%,Faradaic efficiency of 88.60%,yield rate of 316.0 mmol h^(-1)g^(-1)_(Pd+Cu)and long-term stability for consecutive electrolysis within 20 h at-0.55 V vs.reversible hydrogen electrode,outperforming than those of FCC Pd Cu MAs.Under the membrane electrode assembly system,BCC Pd Cu MAs also demonstrate excellent ethylamine yield rate of 389.5 mmol h^(-1)g^(-1)_(Pd+Cu).Density functional theory calculation reveals that the d-d orbital coupling in BCC Pd Cu MAs results in an evident correlation effect for the interaction of Pd and Cu sites,which boosts up the Cu sites electronic activities to enhance ARR performance.Our work opens a new route to develop efficient ARR electrocatalysts from the perspective of crystalline structure transformation. 展开更多
关键词 d-d Orbital coupling Crystal-phase engineering Metallic aerogels Acetonitrile electroreduction reaction ETHYLAMINE
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Naringin ameliorates H_(2)O_(2)-induced oxidative damage in cells and prolongs the lifespan of female Drosophila melanogaster via the insulin signaling pathway
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作者 Xiaomei Du Kexin Wang +7 位作者 Xiaoyan Sang Xiangxing Meng Jiao Xie Tianxin Wang Xiaozhi Liu Qun Huang nan zhang Hao Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1231-1245,共15页
Naringin exists in a wide range of Chinese herbal medicine and has proven to possess several pharmacological properties.In this study,PC12,HepG2 cells,and female Drosophila melanogaster were used to investigate the an... Naringin exists in a wide range of Chinese herbal medicine and has proven to possess several pharmacological properties.In this study,PC12,HepG2 cells,and female Drosophila melanogaster were used to investigate the antioxidative and anti-aging effects of naringin and explore the underlying mechanisms.The results showed that naringin inhibited H_(2)O_(2)-induced decline in cell viability and decreased,the content of reactive oxygen species in cells.Meanwhile,naringin prolonged the lifespan of flies,enhanced the abilities of climbing and the resistance to stress,improved the activities of antioxidant enzymes,and decreased malondialdehyde content.Naringin also improved intestinal barrier dysfunction and reduced abnormal proliferation of intestinal stem cells.Moreover,naringin down-regulated the mRNA expressions of inr,chico,pi 3k,and akt-1,and up-regulated the mRNA expressions of dilp2,dilp3,dilp5,and foxo,thereby activating autophagy-related genes and increasing the number of lysosomes.Furthermore,the mutant stocks assays and computer molecular simulation results further indicated that naringin delayed aging by inhibiting the insulin signaling(IIS)pathway and activating the autophagy pathway,which was consistent with the result of network pharmacological predictions. 展开更多
关键词 Drosophila melanogaster Insulin signaling(IIS)pathway NARINGIN PC12 cell HepG2 cell
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Protein C deficiency with venous and arterial thromboembolic events
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作者 nan zhang Dong-Kun Sun +2 位作者 Xu Tian Xin-Yu Zheng Tong Liu 《World Journal of Clinical Cases》 SCIE 2024年第12期2000-2003,共4页
Protein C(PC)is a key component of the vitamin K-dependent coagulation pathway.It exerts anticoagulant effects by inactivating factors V and VIII.Acquired or inherited PC deficiency results in a prothrombotic state,wi... Protein C(PC)is a key component of the vitamin K-dependent coagulation pathway.It exerts anticoagulant effects by inactivating factors V and VIII.Acquired or inherited PC deficiency results in a prothrombotic state,with presentations varying from asymptomatic to venous thromboembolism.However,there has been an increasing number of reports linking PC deficiency to arterial thromboembolic events,such as myocardial infarction and ischemic stroke.This editorial focuses on the association between PC deficiency and thromboembolism,which may provide some insights for treatment strategy and scientific research. 展开更多
关键词 Protein C deficiency Venous thromboembolism Myocardial infarction EDITORIAL Arterial thromboembolism
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The dominant driving force for supercontinent breakup: Plume push or subduction retreat? 被引量:15
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作者 nan zhang Zhuo Dang +1 位作者 Chuan Huang Zheng-Xiang Li 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第4期997-1007,共11页
Understanding the dominant force responsible for supercontinent breakup is crucial for establishing Earth's geodynamic evolution that includes supercontinent cycles and plate tectonics. Conventionally,two forces h... Understanding the dominant force responsible for supercontinent breakup is crucial for establishing Earth's geodynamic evolution that includes supercontinent cycles and plate tectonics. Conventionally,two forces have been considered: the push by mantle plumes from the sub-continental mantle which is called the active force for breakup, and the dragging force from oceanic subduction retreat which is called the passive force for breakup. However, the relative importance of these two forces is unclear. Here we model the supercontinent breakup coupled with global mantle convection in order to address this question. Our global model features a spherical harmonic degree-2 structure, which includes a major subduction girdle and two large upwelling(superplume) systems. Based on this global mantle structure,we examine the distribution of extensional stress applied to the supercontinent by both subsupercontinent mantle upwellings and subduction retreat at the supercontinent peripheral. Our results show that:(1) at the center half of the supercontinent, plume push stress is ~3 times larger than the stress induced by subduction retreat;(2) an average hot anomaly of no higher than 50 K beneath the supercontinent can produce a push force strong enough to cause the initialization of supercontinent breakup;(3) the extensional stress induced by subduction retreat concentrates on a ~600 km wide zone on the boundary of the supercontinent, but has far less impact to the interior of the supercontinent. We therefore conclude that although circum-supercontinent subduction retreat assists supercontinent breakup, sub-supercontinent mantle upwelling is the essential force. 展开更多
关键词 羽毛 驱动力 初始化 结构 应力 压力 腰带
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High incidence combination of multiple primary malignant tumors of the digestive system 被引量:2
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作者 Xiao-Bo Yang Long-Hao zhang +10 位作者 Jing-nan Xue Yun-Chao Wang Xu Yang nan zhang Dan Liu Yan-Yu Wang Zi-Yu Xun Yi-Ran Li Hui-Shan Sun Li-Jin Zhao Hai-Tao Zhao 《World Journal of Gastroenterology》 SCIE CAS 2022年第41期5982-5992,共11页
BACKGROUND Clinical reports of multiple primary malignant tumors(MPMTs)in the digestive system are increasing.In China,although the survival rate of patients with MPMTs is increasing,the quality of life is very low.Ma... BACKGROUND Clinical reports of multiple primary malignant tumors(MPMTs)in the digestive system are increasing.In China,although the survival rate of patients with MPMTs is increasing,the quality of life is very low.Many patients have reached the advanced stage when the second primary tumor is found,resulting in no early intervention and treatment.This is due to the misunderstanding of MPMTs by clinicians,who treat such tumors as metastases.Therefore,before a patient has a second primary tumor,doctors should understand some common combinations of digestive system MPMTs to provide clinical guidance to the patient.AIM To explore the high incidence combination of digestive system MPMTs under heterochronism and synchronization.METHODS A total of 1902 patients with MPMTs at Peking Union Medical College Hospital were analyzed retrospectively.They were divided into metachronous MPMT and synchronous MPMT groups,and then the high incidence combinations of the first primary cancer and the second primary cancer in metachronous cancer and synchronous cancer were sorted.Sex and age differences between metachronous and synchronous tumors were tested by the chi square test and t test,respectively.A P value<0.05 was considered as statistically significant,and SPSS version 26.0(SPSS Inc.,Chicago,Illinois,United States)was used for statistical analysis.RESULTS Among the 1902 patients with MPMTs confirmed by pathology,1811(95.2%)cases were secondary primary cancers,89(4.7%)cases were tertiary primary cancers,and 2(0.1%)cases were quaternary primary cancers.Most(88.2%)of the secondary primary cancers were identified as metachronous multiple primary cancers six months after diagnosis of the first primary cancer.The top ten most common MPMTs in the first primary cancer group ranged from high to low as follows:Breast cancer,thyroid cancer,nonuterine cancer,lung cancer,colon cancer,kidney cancer,uterine cancer,bladder cancer,rectal cancer,and gastric cancer.The highest incidence rate of the first primary cancer in male metachronous cancer was lung cancer(11.6%),the highest incidence rate of the second primary cancer was still lung cancer(24.9%),the highest incidence rate of the first primary cancer in female metachronous cancer was breast cancer(32.7%),and the highest incidence rate of the second primary cancer was lung cancer(20.8%).Among them,breast cancer,nonuterine cancer and uterine cancer were female-specific malignant tumor types,and thyroid cancer also accounted for 79.6%of female patients.The top five metachronous cancer combinations,independent of female-specific malignant tumor types and thyroid cancer,were colon cancer and lung cancer(26 cases),kidney cancer and lung cancer(25 cases),rectal cancer and lung cancer(20 cases),gastric cancer and lung cancer(17 cases),and bladder cancer and lung cancer(17 cases).The most common synchronous cancer combination was colon cancer and rectal cancer(15 cases).CONCLUSION Screening for lung cancer should be performed six months after the detection of colon cancer while rectal cancer screening should be performed within six months. 展开更多
关键词 Multiple primary malignant tumors Colon cancer Rectal cancer Metachronous carcinoma High incidence combinations First primary carcinoma
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Nanocomposites of graphene-CdS as photoactive and reusable catalysts for visible-light-induced selective reduction process 被引量:1
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作者 Siqi Liu Min-Quan Yang +1 位作者 nan zhang Yi-Jun Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第2期145-155,共11页
Graphene(GR)-CdS nanocomposites with different weight addition ratios of GR have been assembled by a facile solvothermal treatment. The GR-CdS nanocomposite photocatalyst with an appropriate ratio of GR exhibits enhan... Graphene(GR)-CdS nanocomposites with different weight addition ratios of GR have been assembled by a facile solvothermal treatment. The GR-CdS nanocomposite photocatalyst with an appropriate ratio of GR exhibits enhanced photoactivity for selective reduction of aromatic nitro compounds to the corresponding aromatic amines in water under visible light irradiation as compared with blank-CdS. The characterization of GR-CdS nanocomposite photocatalysts by a collection of techniques discloses that: i) GR can tune the microscopic morphology of CdS nanoparticles and improve light absorption intensity in the visible light region; ii) GR scaffolds act as an electron reservoir to trap and shuttle the electrons photogenerated from CdS semiconductor under the visible light illumination; iii) the introduction of GR enhances the adsorption capacity of GR-CdS nanocomposites toward the substrates, aromatic nitro compounds. The synergistic effect of these factors should account for the photoactivity advancement of GR-CdS nanocomposites toward the probe reactions. Furthermore, because the photogenerated holes in the system are trapped by the quenching agent ammonium oxalate, the as-obtained GR-CdS photocatalyst is stable during the photocatalytic reduction reactions. A reasonable model has also been proposed to illustrate the reaction mechanism. 展开更多
关键词 纳米复合光催化剂 纳米复合材料 硫化镉 可重复使用 还原过程 石墨 芳香族硝基化合物 CdS纳米颗粒
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Novel cellular therapies for hepatobiliary malignancies 被引量:1
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作者 Jing-nan Xue Yan-Yu Wang +5 位作者 Yun-Chao Wang nan zhang Long-Hao zhang Zheng-Hui Lu Li-Jin Zhao Hai-Tao Zhao 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2022年第5期450-454,共5页
Background:The mortalities of hepatobiliary malignancies are high.With the failure of conventional chemotherapy and unsatisfactory outcome of molecular targeted drugs,immune-based therapy has become a new focus of res... Background:The mortalities of hepatobiliary malignancies are high.With the failure of conventional chemotherapy and unsatisfactory outcome of molecular targeted drugs,immune-based therapy has become a new focus of research in hepatobiliary cancers treatment.Data sources:We performed a Pub Med search with relevant articles published up to May 2022 and the following keywords:cellular immunotherapy,hepatobiliary cancer,antigen receptor T cell therapy,and receptor-engineered T cell.Information of clinical trials was obtained from https://clinicaltrials.gov/.Results:Cell therapies for hepatobiliary malignancies are at early stage of development.The current review showed that cellular therapies are safe and feasible in patients.These findings provide an important platform for future lager scale clinical trials on immunotherapy in patients with hepatobiliary malignancies.Conclusions:With the continuous advances of cellular immunotherapy,the combination of cellular immunotherapy with surgery,chemotherapy and radiotherapy will be new therapeutic strategies for patients with hepatobiliary cancer. 展开更多
关键词 Cellular therapy Chimeric antigen receptor T cell therapy Receptor-engineered T cell Hepatobiliary malignancy
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Stable overall water splitting in an asymmetric acid/ alkaline electrolyzer comprising a bipolar membrane sandwiched by bifunctional cobalt-nickel phosphide nanowire electrodes
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作者 Junyuan Xu Isilda Amorim +6 位作者 Yue Li Junjie Li Zhipeng Yu Bingsen zhang Ana Araujo nan zhang Lifeng Liu 《Carbon Energy》 CAS 2020年第4期646-655,共10页
Water splitting has been proposed to be a promising approach to producing clean hydrogen fuel.The two half-reactions of water splitting,that is,the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),ta... Water splitting has been proposed to be a promising approach to producing clean hydrogen fuel.The two half-reactions of water splitting,that is,the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),take place kinetically fast in solutions with completely different pH values.Enabling HER and OER to simultaneously occur under kinetically favorable conditions while using exclusively low-cost,earth-abundant electrocatalysts is highly desirable but remains a challenge.Herein,we demonstrate that using a bipolar membrane(BPM)we can accomplish HER in a strongly acidic solution and OER in a strongly basic solution,with bifunctional self-supported cobaltnickel phosphide nanowire electrodes to catalyze both reactions.Such asymmetric acid/alkaline water electrolysis can be achieved at 1.567 V to deliver a current density of 10 mA/cm2 with ca.100%Faradaic efficiency.Moreover,using an“irregular”BPM with unintentional crossover the voltage needed to afford 10 mA/cm2 can be reduced to 0.847 V,due to the assistance of electrochemical neutralization between acid and alkaline.Furthermore,we show that BPM-based asymmetric water electrolysis can be accomplished in a circulated single-cell electrolyzer delivering 10 mA/cm2 at 1.550 V and splitting water very stably for at least 25 hours,and that water electrolysis is enabled by a solar panel operating at 0.908 V(@13 mA/cm2),using an“irregular”BPM.BPMbased asymmetric water electrolysis is a promising alternative to conventional proton and anion exchange membrane water electrolysis. 展开更多
关键词 bipolar membrane cobalt nickel phosphide hydrogen production noble metalfree water splitting
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Enhanced Nonlinear Absorption Performance of Reduced Graphene Oxide Nanohybrid Covalently Functionalized by Porphyrin via 1,3-Dipolar Cycloaddition
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作者 nan zhang Xiaoqing Cong 《Materials Sciences and Applications》 2018年第12期972-984,共13页
Porphyrin-functionalized reduced graphene oxide (RGO-TPP) was prepared by 1,3-dipolar cycloaddition reaction and characterized by Fourier transform infrared spectroscopy, Raman, ultraviolet/visible absorption, fluores... Porphyrin-functionalized reduced graphene oxide (RGO-TPP) was prepared by 1,3-dipolar cycloaddition reaction and characterized by Fourier transform infrared spectroscopy, Raman, ultraviolet/visible absorption, fluorescence, and transmission electron microscopy. At the same level of linear transmittance, RGO-TPP exhibited more enhanced optical nonlinearities than RGO and the pristineporphyrin, implying a remarkable accumulation effect as a result of the covalent link between RGO and porphyrin. The role of energy/electron transfer in the optical nonlinearities of RGO-TPP was investigated by fluorescence and Raman spectroscopy. All the results displayed that RGO can be covalently functionalized with porphyrins by the proposed approach. 展开更多
关键词 Reduced Graphene OXIDE PORPHYRINOIDS CYCLOADDITION Reaction Nonlinear Optics
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中心电子富集的NO-FeN_(4)位点作为质子交换膜燃料电池的高级酸性氧还原反应电催化剂
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作者 钟程安 周天培 +8 位作者 张楠 陈明龙 谢友学 闫文盛 储旺盛 郑旭升 徐倩 葛建开 吴长征 《中国科学技术大学学报》 CAS CSCD 北大核心 2023年第3期37-45,I0002,I0003,共11页
开发非贵金属催化剂,特别是用于碳上铁氮(FeNC)材料的催化剂,对于质子交换膜燃料电池(PEMFC)的广泛应用是一个迫切需求。然而,传统铁氮位点在酸性条件下的氧还原反应(ORR)活性较差,严重阻碍了其电池性能的进一步提高。本文通过限域的小... 开发非贵金属催化剂,特别是用于碳上铁氮(FeNC)材料的催化剂,对于质子交换膜燃料电池(PEMFC)的广泛应用是一个迫切需求。然而,传统铁氮位点在酸性条件下的氧还原反应(ORR)活性较差,严重阻碍了其电池性能的进一步提高。本文通过限域的小分子合成策略,大规模合成了具有一氧化氮(NO)基团轴向修饰的FeN_(4)(表示为NO-FeN_(4))。得益于NO基团的强吸电子效应,与传统的FeN_(4)样品相比,富含电子中心FeN_(4)位点表现出超高的ORR活性,具有三倍高的质量活性(0.85 V时为1.1 A·g^(−1)),以及全四电子反应选择性。此外,用所制备的电催化剂组装的质子交换膜燃料电池也表现出显著增强的峰值功率密度(>725 mW·cm^(−2))。这项工作为合理设计用于氧还原的先进M-Nx非贵金属电催化剂提供了一种新的方法。 展开更多
关键词 大规模定制合成 氧还原反应 质子交换膜燃料电池 限域小分子合成
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High-performance flexible perovskite photodetectors based on single-crystal-like two-dimensional Ruddlesden-Popper thin films 被引量:5
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作者 Chao Liang Hao Gu +5 位作者 Junmin Xia Tanghao Liu Shiliang Mei nan zhang Yonghua Chen Guichuan Xing 《Carbon Energy》 SCIE CSCD 2023年第2期250-259,共10页
Two-dimensional Ruddlesden-Popper(2DRP)perovskites have attracted intense research interest for optoelectronic applications,due to their tunable optoelectronic properties and better environmental stability than their ... Two-dimensional Ruddlesden-Popper(2DRP)perovskites have attracted intense research interest for optoelectronic applications,due to their tunable optoelectronic properties and better environmental stability than their threedimensional counterparts.Furthermore,high-performance photodetectors based on single-crystal and polycrystalline thin-films 2DRP perovskites have shown great potential for practical application.However,the complex growth process of single-crystal membranes and uncontrollable phase distribution of polycrystalline films hinder the further development of 2DRP perovskites photodetectors.Herein,we report a series of high-performance photodetectors based on single-crystal-like phase-pure 2DRP perovskite films by designing a novel spacer source.Experimental and theoretical evidence demonstrates that phase-pure films substantially suppress defect states and ion migration.These highly sensitive photodetectors show I_(light)/I_(dark) ratio exceeding 3×10^(4),responsivities exceeding 16 A/W,and detectivities exceeding 3×10^(13) Jones,which are higher at least by 1 order than those of traditional mixed-phase thinfilms 2DRP devices(close to the reported single-crystal devices).More importantly,this strategy can significantly enhance the operational stability of optoelectronic devices and pave the way to large-area flexible productions. 展开更多
关键词 FLEXIBILITY PHOTODETECTORS single-crystal-like stability two-dimensional perovskites
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Geostructures, dynamics and risk mitigation of high-altitude and long- runout rockslides 被引量:1
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作者 Yueping Yin Bin Li +3 位作者 Yang Gao Wenpei Wang Shilin zhang nan zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第1期66-101,共36页
Long-runout rockslides at high altitude could cause disaster chain in river basins and destroy towns and major infrasturctures.This paper firstly explores the initiation mechanism of high-altitude and long-runout rock... Long-runout rockslides at high altitude could cause disaster chain in river basins and destroy towns and major infrasturctures.This paper firstly explores the initiation mechanism of high-altitude and long-runout rockslides.Two types of sliding-prone geostructure models,i.e.the fault control type in orogenic belt and the fold control type in platform area,are proposed.Then,large-scale experimental apparatus and associated numerical simulations are conducted to understanding the chain-style dynamics of rockslide-debris avalanche-debris flow.The results reveal the fragmentation effects,the rheological behaviors and the boundary layer effect of long-runout avalanche-debris flow.The dynamic character-istics of quasi-static-transition-inertia state and solid-liquid coupling in rapid movement of rockslide-debris avalanche-debris flow are investigated.Finally,the risk mitigation strategy of the non-structure and structure for resilient energy dissipation are illustrated for initiation,transition and deposition zones.The structural prevention and mitigation methods have been successfully applied to the high-altitude and long-runout rockslides in Zhouqu and Maoxian of the Wenchuan earthquake zone,as well as the other major geohazards in Qinghai-Tibet Plateau and its adjacent areas. 展开更多
关键词 ROCKSLIDE High-altitude and long-runout Sliding-prone geostructure Large-scale experimental apparatus Risk mitigation strategy Structural prevention technique
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Clinical outcomes of lenvatinib plus transarterial chemoembolization with or without programmed death receptor-1 inhibitors in unresectable hepatocellular carcinoma 被引量:1
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作者 Yan-Yu Wang Xu Yang +12 位作者 Yun-Chao Wang Jun-Yu Long Hui-Shan Sun Yi-Ran Li Zi-Yu Xun nan zhang Jing-nan Xue Cong Ning Jun-Wei zhang Cheng-Pei Zhu Long-Hao zhang Xiao-Bo Yang Hai-Tao Zhao 《World Journal of Gastroenterology》 SCIE CAS 2023年第10期1614-1626,共13页
BACKGROUND Programmed death receptor-1(PD-1)inhibitors have been approved as secondline treatment regimen in hepatocellular carcinoma(HCC),but it is still worth studying whether patients can benefit from PD-1 inhibito... BACKGROUND Programmed death receptor-1(PD-1)inhibitors have been approved as secondline treatment regimen in hepatocellular carcinoma(HCC),but it is still worth studying whether patients can benefit from PD-1 inhibitors as first-line drugs combined with targeted drugs and locoregional therapy.AIM To estimate the clinical outcome of transarterial chemoembolization(TACE)and lenvatinib plus PD-1 inhibitors for patients with unresectable HCC(uHCC).METHODS We carried out retrospective research of 65 patients with uHCC who were treated at Peking Union Medical College Hospital from September 2017 to February 2022.45 patients received the PD-1 inhibitors,lenvatinib,TACE(PD-1-Lenv-T)therapy,and 20 received the lenvatinib,TACE(Lenv-T)therapy.In terms of the dose of lenvatinib,8 mg was given orally for patients weighing less than 60 kg and 12 mg for those weighing more than 60 kg.Of the patients in the PD-1 inhibitor combination group,15 received Toripalimab,14 received Toripalimab,14 received Camrelizumab,4 received Pembrolizumab,9 received Sintilimab,and 2 received Nivolumab,1 with Tislelizumab.According to the investigators’assessment,TACE was performed every 4-6 wk when the patient had good hepatic function(Child-Pugh class A or B)until disease progression occurred.We evaluated the efficacy by the modified Response Evaluation Criteria in Solid Tumors(mRECIST criteria).We accessd the safety by the National Cancer Institute Common Terminology Criteria for Adverse Events,v 5.0.The key adverse events(AEs)after the initiation of combination therapy were observed.RESULTS Patients with uHCC who received PD-1-Lenv-T therapy(n=45)had a clearly longer overall survival than those who underwent Lenv-T therapy(n=20,26.8 vs 14.0 mo;P=0.027).The median progression-free survival time between the two treatment regimens was also measured{11.7 mo[95%confidence interval(CI):7.7-15.7]in the PD-1-Lenv-T group vs 8.5 mo(95%CI:3.0-13.9)in the Lenv-T group(P=0.028)}.The objective response rates of the PD-1-Lenv-T group and Lenv-T group were 44.4%and 20%(P=0.059)according to the mRECIST criteria,meanwhile the disease control rates were 93.3%and 64.0%(P=0.003),respectively.The type and frequency of AEs showed little distinction between patients received the two treatment regimens.CONCLUSION Our results suggest that the early combination of PD-1 inhibitors has manageable toxicity and hopeful efficacy in patients with uHCC. 展开更多
关键词 Lenvatinib Programmed death receptor-1 inhibitor IMMUNOTHERAPY Hepatocellular carcinoma Transarterial chemoembolization Combination therapy
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Surface Passivation Toward Efficient and Stable Perovskite Solar Cells 被引量:1
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作者 Junmin Xia Chao Liang +6 位作者 Hao Gu Shiliang Mei Shengwen Li nan zhang Shi Chen Yongqing Cai Guichuan Xing 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第1期1-24,共24页
Although metal halide perovskites are increasingly popular for the next generation of efficient photovoltaic devices,the inevitable defects from the preparation process have become the notorious barrier to further imp... Although metal halide perovskites are increasingly popular for the next generation of efficient photovoltaic devices,the inevitable defects from the preparation process have become the notorious barrier to further improvement of performance,which increases non-radiative recombination and lowers the power conversion efficiency of solar cells.Surface passivation strategies have been affirmed as one of the most practical approaches to suppress these defects.Therefore,it is necessary to have a detailed review on the surface passivation to reveal the improvements of the devices.Herein,the mechanism and recent advances of surface passivation have been systematically summarized with respect to various passivation approaches,including the Lewis acid–base,the low-dimensional perovskite,inorganic molecules,and polymers.Finally,the review also offers the research trend and prospects of surface passivation. 展开更多
关键词 DEFECTS EFFICIENCY perovskite solar cells stability surface passivation
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双光子吸收表征及相关光物理机制
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作者 张楠 臧建阳 +1 位作者 王刚 刘太宏 《大学化学》 CAS 2023年第1期88-96,共9页
双光子吸收材料在高分辨生物成像、光动力学治疗和光限幅等领域备受关注。新型双光子吸收材料创制涉及非线性光学性质表征、光物理机制解析和构效关系构建。本文探讨了双光子吸收相关的光物理跃迁机制、开孔Z-扫描与双光子激发荧光方法... 双光子吸收材料在高分辨生物成像、光动力学治疗和光限幅等领域备受关注。新型双光子吸收材料创制涉及非线性光学性质表征、光物理机制解析和构效关系构建。本文探讨了双光子吸收相关的光物理跃迁机制、开孔Z-扫描与双光子激发荧光方法的区别联系以及激光光源特性对双光子吸收性能测试结果的影响,最后对该领域进行展望。 展开更多
关键词 双光子吸收 非线性光学 光物理 荧光
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