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A single micro-LED manipulation system based on micro-gripper 被引量:2
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作者 jie bai Pingjuan Niu +2 位作者 Erdan Gu Jianming Li Clarence Augustine TH Tee 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期41-48,共8页
Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techni... Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techniques involved in the fabrication ofμLED-based devices is transfer printing.Although numerous methods have been proposed for transfer printing,improving the yield ofμLED arrays is still a formidable task.In this paper,we propose a novel method for improving the yield ofμLED arrays transferred by the stamping method,using an innovative design of piezoelectrically driven asymmetric micro-gripper.Traditional grippers are too large to manipulateμLEDs,and therefore two micro-sized cantilevers are added at the gripper tips.AμLED manipulation system is constructed based on the micro-gripper together with a three-dimensional positioning system.Experimental results using this system show that it can be used successfully to manipulateμLED arrays. 展开更多
关键词 MICRO-GRIPPER Micro-LED Transfer printing MANIPULATION
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Polypyride intercalation boosting the kinetics and stability of V_(3)O_(7)·H_(2)O cathodes for aqueous zinc-ion batteries
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作者 Qingqing He jie bai +4 位作者 Mengda Xue Yanxin Liao Huayu Wang Mujun Long Lingyun Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期361-370,I0007,共11页
V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical conductivity.In this paper,polypyridine(PPyd)i... V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical conductivity.In this paper,polypyridine(PPyd)intercalated VO with nanoribbon structure was prepared by a simple in-situ pre-intercalation,which is noted VO-PPyd.The total density of states(TDOS)shows that after the pre-intercalation of PPyd,an intermediate energy level appears between the valence band and conduction band,which provides a step that can effectively reduce the band gap and enhance the electron conductivity.Furthermore,the density functional theory(DFT)results found that Zn^(2+)is more easily de-intercalated from the V-O skeleton,which proves that the embeddedness of PPyd improves the diffusion kinetics of Zn^(2+).Electrochemical studies have shown that VO-PPyd cathode materials exhibit excellent rate performance(high specific capacity of 465 and 192 mA h g^(-1)at 0.2 and 10 A g^(-1),respectively)and long-term cycling performance(92.7%capacity retention rate after 5300 cycles),due to their advantages in structure and composition.More importantly,the energy density of VO-PPyd//Zn at 581 and 5806 W kg^(-1)is 375 and 247 W h kg^(-1),respectively.VO-PPyd exhibits excellent electrochemical properties compared to previously reported vanadium based cathodes,which makes it highly competitive in the field of high-performance cathode materials of AZIBs. 展开更多
关键词 V_(3)O_(7)·H_(2)O POLYPYRIDINE Ion migration Electrical conductivity Aqueous zinc ion batteries DFT calculation
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m6A修饰在肿瘤细胞自噬中的作用
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作者 白洁 苏夏艺 +3 位作者 魏秀珍 董亚玲 朱志博(综述) 张百红(审校) 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第15期795-800,共6页
自噬是一种细胞自我降解过程,在维持细胞和生物体代谢功能中起着至关重要的作用。自噬功能失调与包括肿瘤在内的多种疾病有关。m^(6)A修饰作为真核生物体内主要的RNA内部修饰,通过影响自噬相关基因(autophagy associated gene,ATG)的表... 自噬是一种细胞自我降解过程,在维持细胞和生物体代谢功能中起着至关重要的作用。自噬功能失调与包括肿瘤在内的多种疾病有关。m^(6)A修饰作为真核生物体内主要的RNA内部修饰,通过影响自噬相关基因(autophagy associated gene,ATG)的表达或干扰自噬相关信号通路在调节肿瘤细胞自噬过程中发挥重要作用,异常的m^(6)A修饰会导致自噬失调并影响肿瘤的进展。然而,其在肿瘤自噬调控中的具体作用仍待探索。因此,本文综述了m^(6)A修饰在肿瘤细胞自噬中的作用,并探讨了其与肿瘤进展及其耐药的关系,旨在为开发新的治疗策略提供理论基础。 展开更多
关键词 自噬 m^(6)A甲基转移酶 m^(6)A脱甲基转移酶 m^(6)A结合蛋白 肿瘤 耐药
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Impact of Osmotic Pressure on Seepage in Shale Oil Reservoirs
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作者 Lijun Mu Xiaojia Xue +2 位作者 jie bai Xiaoyan Li Xueliang Han 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1365-1379,共15页
Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the sh... Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the shut-in phase in augmenting shale oil productivity.Unlike conventional reservoirs,shale oil reservoirs exhibit characteristics such as low porosity,low permeability,and rich content of organic matter and clay minerals.Notably,the osmotic pressure effects occurring between high-salinity formation water and low-salinity fracturing fluids are significant.The current understanding of the mobilization patterns of crude oil in micro-pores during the imbibition process remains nebulous,and the mechanisms underpinning osmotic pressure effects are not fully understood.This study introduces a theoretical approach,by which a salt ion migration control equation is derived and a mathematical model for spontaneous imbibition in shale is introduced,which is able to account for both capillary and osmotic pressures.Results indicate that during the spontaneous imbibition of low-salinity fluids,osmotic effects facilitate the migration of external fluids into shale pores,thereby complementing capillary forces in displacing shale oil.When considering both capillary and osmotic pressures,the calculated imbibition depth increases by 12%compared to the case where only capillary forces are present.The salinity difference between the reservoir and the fracturing fluids significantly influences the imbibition depth.Calculations for the shutin phase reveal that the pressure between the matrix and fractures reaches a dynamic equilibrium after 28 days of shut-in.During the production phase,the maximum seepage distance in the target block is approximately 6.02 m. 展开更多
关键词 Shale oil osmotic pressure numerical simulation effective seepage distance
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超声滚压对6061铝合金第二相诱发局部腐蚀的影响 被引量:2
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作者 樊磊 李波 +6 位作者 何锦航 白洁 毛进 张有佳 黄朝文 李伟 石维 《材料工程》 EI CAS CSCD 北大核心 2023年第9期128-139,共12页
采用超声滚压技术(USRP)改变6061铝合金表层,实现不同静压力下USRP对6061铝合金第二相组织的改变,从而提高铝合金的耐腐蚀性能。使用SEM,SKPFM以及激光共聚焦等手段,基于微区电偶腐蚀原理,在考虑溶液阻抗与氧化物阻抗的条件下,得出第二... 采用超声滚压技术(USRP)改变6061铝合金表层,实现不同静压力下USRP对6061铝合金第二相组织的改变,从而提高铝合金的耐腐蚀性能。使用SEM,SKPFM以及激光共聚焦等手段,基于微区电偶腐蚀原理,在考虑溶液阻抗与氧化物阻抗的条件下,得出第二相尺寸与局部腐蚀发展的关联规律,并利用激光共聚焦显微镜原位观察,验证第二相尺寸对局部腐蚀发展的影响。结果表明:当铝合金表层经0.10 MPa静压力滚压时,在3.5%(质量分数)NaCl溶液中的初期自腐蚀电流密度仅为未处理试样的1/15,腐蚀速率降低了93.04%。Mg2Si相在滚压过程中并未发生显著形态变化,对USRP前后腐蚀性能变化无显著影响。长条状连续分布的AlFeSi相会在USRP作用下细化为微纳尺度的弥散状分布。充分细化后的AlFeSi相会因腐蚀微电池的局部阴阳极面积比减少而减弱电偶腐蚀效应,虽会促进铝合金基体的亚稳态点蚀形核率,但同时也会造成自身的快速溶解。当自溶解发生或在亚稳态蚀孔内壁形成Al2O3氧化膜保护时,AlFeSi相对铝合金基体电偶腐蚀效应大幅减弱,从而提高6061铝合金整体的耐腐蚀性能。 展开更多
关键词 6061铝合金 超声滚压 AlFeSi相 局部腐蚀 电偶腐蚀
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Development of a model based on the age-adjusted Charlson comorbidity index to predict survival for resected perihilar cholangiocarcinoma 被引量:6
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作者 Yu Pan Zhi-Peng Liu +15 位作者 Hai-Su Dai Wei-Yue Chen Ying Luo Yu-Zhu Wang Shu-Yang Gao Zi-Ran Wang Jin-Ling Dong Yun-Hua Liu Xian-Yu Yin Xing-Chao Liu Hai-Ning Fan jie bai Yan Jiang Jun-jie Cheng Yan-Qi Zhang Zhi-Yu Chen 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第6期1036-1050,共15页
BACKGROUND Perihilar cholangiocarcinoma(pCCA)has a poor prognosis and urgently needs a better predictive method.The predictive value of the age-adjusted Charlson comorbidity index(ACCI)for the long-term prognosis of p... BACKGROUND Perihilar cholangiocarcinoma(pCCA)has a poor prognosis and urgently needs a better predictive method.The predictive value of the age-adjusted Charlson comorbidity index(ACCI)for the long-term prognosis of patients with multiple malignancies was recently reported.However,pCCA is one of the most surgically difficult gastrointestinal tumors with the poorest prognosis,and the value of the ACCI for the prognosis of pCCA patients after curative resection is unclear.AIM To evaluate the prognostic value of the ACCI and to design an online clinical model for pCCA patients.METHODS Consecutive pCCA patients after curative resection between 2010 and 2019 were enrolled from a multicenter database.The patients were randomly assigned 3:1 to training and validation cohorts.In the training and validation cohorts,all patients were divided into low-,moderate-,and high-ACCI groups.Kaplan-Meier curves were used to determine the impact of the ACCI on overall survival(OS)for pCCA patients,and multivariate Cox regression analysis was used to determine the independent risk factors affecting OS.An online clinical model based on the ACCI was developed and validated.The concordance index(C-index),calibration curve,and receiver operating characteristic(ROC)curve were used to evaluate the predictive performance and fit of this model.RESULTS A total of 325 patients were included.There were 244 patients in the training cohort and 81 patients in the validation cohort.In the training cohort,116,91 and 37 patients were classified into the low-,moderate-and high-ACCI groups.The Kaplan-Meier curves showed that patients in the moderate-and high-ACCI groups had worse survival rates than those in the low-ACCI group.Multivariable analysis revealed that moderate and high ACCI scores were independently associated with OS in pCCA patients after curative resection.In addition,an online clinical model was developed that had ideal C-indexes of 0.725 and 0.675 for predicting OS in the training and validation cohorts.The calibration curve and ROC curve indicated that the model had a good fit and prediction performance.CONCLUSION A high ACCI score may predict poor long-term survival in pCCA patients after curative resection.High-risk patients screened by the ACCI-based model should be given more clinical attention in terms of the management of comorbidities and postoperative follow-up. 展开更多
关键词 Perihilar cholangiocarcinoma Age-adjusted Charlson comorbidity index RESECTION SURVIVAL MODEL PROGNOSIS
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Pea-like MoS_(2)@NiS_(1.03)-carbon heterostructured hollow nanofibers for high-performance sodium storage 被引量:4
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作者 Songwei Gao Yixiang He +10 位作者 Guichu Yue Huaike Li Shuai Li Jingchong Liu Beibei Miao jie bai Zhimin Cui Nu Wang Qianfan Zhang Lei Jiang Yong Zhao 《Carbon Energy》 SCIE CSCD 2023年第4期42-54,共13页
The rational synergy of chemical composition and spatial nanostructures of electrode materials play important roles in high-performance energy storage devices.Here,we designed pea-like MoS_(2)@NiS_(1.03)-carbon hollow... The rational synergy of chemical composition and spatial nanostructures of electrode materials play important roles in high-performance energy storage devices.Here,we designed pea-like MoS_(2)@NiS_(1.03)-carbon hollow nanofibers using a simple electrospinning and thermal treatment method.The hierarchical hollow nanofiber is composed of a nitrogen-doped carbon-coated NiS_(1.03) tube wall,in which pea-like uniformly discrete MoS_(2) nanoparticles are enclosed.As a sodium-ion battery electrode material,the MoS_(2)@NiS_(1.03)-carbon hollow nanofibers have abundant diphasic heterointerfaces,a conductive network,and appropriate volume variation-buffering spaces,which can facilitate ion diffusion kinetics,shorten the diffusion path of electrons/ion,and buffer volume expansion during Na^(+)insertion/extraction.It shows outstanding rate capacity and long-cycle performance in a sodium-ion battery.This heterogeneous hollow nanoarchitectures designing enlightens an efficacious strategy to boost the capacity and long-life stability of sodium storage performance of electrode materials. 展开更多
关键词 density functional theory electrospinning HETEROSTRUCTURE hollow nanofibers molybdenum disulfide sodium-ion batteries
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Numerical study of hydraulic fracturing in the sectorial well-factory considering well interference and stress shadowing 被引量:1
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作者 Yu-Hao Liu Jin-Tao Zhang +2 位作者 jie bai Feng-Shou Zhang Ji-Zhou Tang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3567-3581,共15页
In the Changqing Oilfield in northwest China, when traditional petroleum exploitation encounters forestry reserves or water source protection areas, sectorial well-factory design is proposed. The most distinct feature... In the Changqing Oilfield in northwest China, when traditional petroleum exploitation encounters forestry reserves or water source protection areas, sectorial well-factory design is proposed. The most distinct feature of a sectorial well-factory is the deviation of the well from the minimum horizontal principal stress, resulting in hydraulic fracture deflection after the initiation, along with possible well interference (i.e., fracture hit) and fracture coalescence in the oblique wells. Four indexes describing well deflection are then proposed according to fracture morphology. Several fracturing designs, including stage arrangement, fracturing sequences, and fracturing techniques are applied to study the feasibility of the sectorial well-factory design. The results show that the “gradual” or “sparse” stage arrangement, large injection rate, and simultaneous multifracture treatment can help to optimize the fracture morphology and stimulation design. However, the subsequent stress shadowing effect usually adversely affects the fracturing of adjacent wells. With a small initial horizontal stress difference, large injection rate and staggered stage arrangement can achieve ideal stimulation performance. Our results can provide a guidance for optimizing stimulation design in unconventional well-factory while taking into account environmental protection. 展开更多
关键词 Hydraulic fracturing Sectorial well-factory Fracture deflection Well interference Stress shadowing
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Review of a direct epitaxial approach to achieving micro-LEDs 被引量:1
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作者 蔡月飞 白洁 王涛 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期22-29,共8页
There is a significantly increasing demand of developing augmented reality and virtual reality(AR and VR) devices,where micro-LEDs(μLEDs) with a dimension of ≤ 5 μm are the key elements. Typically, μLEDs are fabri... There is a significantly increasing demand of developing augmented reality and virtual reality(AR and VR) devices,where micro-LEDs(μLEDs) with a dimension of ≤ 5 μm are the key elements. Typically, μLEDs are fabricated by dry-etching technologies, unavoidably leading to a severe degradation in optical performance as a result of dry-etching induced damages. This becomes a particularly severe issue when the dimension of LEDs is ≤ 10 μm. In order to address the fundamental challenge, the Sheffield team has proposed and then developed a direct epitaxial approach to achievingμLEDs, where the dry-etching technologies for the formation of μLED mesas are not needed anymore. This paper provides a review on this technology and then demonstrates a number of monolithically integrated devices on a single chip using this technology. 展开更多
关键词 micro-LED epitaxial growth gallium nitride DISPLAY
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Effect of hydraulic fracturing induced stress field on weak surface activation during unconventional reservoir development
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作者 jie bai Xiao-Qiong Wang +2 位作者 Hong-Kui Ge Hu Meng Ye-Qun Wen 《Petroleum Science》 SCIE EI CSCD 2023年第5期3119-3130,共12页
Unconventional reservoirs usually contain many weak surfaces such as faults,laminae and natural fractures,and effective activation and utilization of these weak surfaces in reservoirs can significantly improve the ext... Unconventional reservoirs usually contain many weak surfaces such as faults,laminae and natural fractures,and effective activation and utilization of these weak surfaces in reservoirs can significantly improve the extraction effect.In hydraulic fracturing,when the artificial fracture approaches the natural fracture,the natural fracture would be influenced by both the original in-situ stress field and the hydraulic fracturing-induced stress field.In this paper,the hydraulic fracturing-induced stress field is calculated based on the relative position of hydraulic fracture and natural fracture,the original in-situ stress,the net pressure inside the hydraulic fracture and the pore pressure of the formation.Furthermore,the stability model of the natural fracture is established by combining the Mohr-Coulomb rupture criterion,and extensive parametric studies are conducted to explore the impact of each parameter on the stability of the natural fracture.The validity of the proposed model is verified by comparing with the reservoir characteristics and fracturing process of the X-well 150e155 formation in the Songliao Basin.It is found that the stress field induced by the hydraulic fracture inhibits the activation of the natural fracture after the artificial fracture crossed the natural fracture.Therefore,for similar reservoirs as X-well 150e155,it is suggested to connect natural fractures with hydraulic fractures first and then activate natural fractures which can effectively utilize the natural fractures and form a complex fracture network. 展开更多
关键词 Hydraulic fracturing Induced stress field Weak surface Natural fracture stability Fracturing characteristics
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Clinical implications of forkhead box M1, cyclooxygenase-2, and glucose-regulated protein 78 in breast invasive ductal carcinoma
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作者 jie bai Ying Li Li Cai 《World Journal of Clinical Cases》 SCIE 2023年第30期7284-7293,共10页
BACKGROUND Breast infiltrating ductal carcinoma(BIDC)represents the largest heterotypic tumor group,and an in-depth understanding of the pathogenesis of BIDC is key to improving its prognosis.AIM To analyze the expres... BACKGROUND Breast infiltrating ductal carcinoma(BIDC)represents the largest heterotypic tumor group,and an in-depth understanding of the pathogenesis of BIDC is key to improving its prognosis.AIM To analyze the expression profiles and clinical implications of forkhead box M1(FOXM1),cyclooxygenase-2(COX-2),and glucose-regulated protein 78(GRP78)in BIDC.METHODS A total of 65 BIDC patients and 70 healthy controls who presented to our hospital between August 2019 and May 2021 were selected for analysis.The peripheral blood FOXM1,COX-2,and GRP78 levels in both groups were measured and the association between their expression profiles in BIDC was examined.Additionally,we investigated the diagnostic value of FOXM1,COX-2,and GRP78 in patients with BIDC and their correlations with clinicopathological features.Furthermore,BIDC patients were followed for 1 year to identify factors influencing patient prognosis.RESULTS The levels of FOXM1,COX-2,and GRP78 were significantly higher in BIDC patients compared to healthy controls(P<0.05),and a positive correlation was observed among them(P<0.05).Receiver operating characteristic analysis demonstrated that FOXM1,COX-2,and GRP78 had excellent diagnostic value in predicting the occurrence of BIDC(P<0.05).Subsequently,we found significant differences in FOXM1,COX-2,and GRP78 levels among patients with different histological grades and metastasis statuses(with vs without)(P<0.05).Cox analysis revealed that FOXM1,COX-2,GRP78,increased histological grade,and the presence of tumor metastasis were independent risk factors for prognostic death in BIDC(P<0.001).CONCLUSION FOXM1,COX-2,and GRP78 exhibit abnormally high expression in BIDC,promoting malignant tumor development and closely correlating with prognosis.These findings hold significant research implications for the future diagnosis and treatment of BIDC. 展开更多
关键词 Diagnostic value Forkhead box M1 CYCLOOXYGENASE-2 Glucose-regulated protein 78 Clinical implications
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完全胸腔镜下解剖性肺段切除术治疗早期肺癌的体会 被引量:33
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作者 马少华 闫天生 +7 位作者 王可毅 王京第 宋金涛 王通 贺未 白洁 金亮 梁海龙 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第2期99-103,共5页
背景与目的肺段切除较肺叶切除能够更多地保留健康肺组织,但其在早期肺癌根治性方面仍存在争议。本研究分析35例完全胸腔镜下解剖性肺段切除术临床病理资料并复习文献,探讨胸腔镜下肺段切除术在早期肺癌治疗中面临的问题。方法回顾北京... 背景与目的肺段切除较肺叶切除能够更多地保留健康肺组织,但其在早期肺癌根治性方面仍存在争议。本研究分析35例完全胸腔镜下解剖性肺段切除术临床病理资料并复习文献,探讨胸腔镜下肺段切除术在早期肺癌治疗中面临的问题。方法回顾北京大学第三医院2013年5月-2017年7月单一手术组35例完全胸腔镜下肺段切除术患者的临床病理资料,观察术中及术后并发症等安全性指标及淋巴结清扫数目、转移情况,并将术后病理类型与术前影像类型比对分析。35例肺段切除术中男性11例,女性24例,平均年龄57.7岁。病灶位于右肺上叶者8例,右肺下叶者8例,左肺上叶者13例,左肺下叶者6例。计算机断层扫描(computed tomography,CT)影像学肿瘤最大径平均12.7 mm,肺门及纵隔淋巴结最大直径均小于10 mm,以磨玻璃成为主者23例,以实性成分为主者12例。结果 35例均顺利完成电视辅助胸腔镜手术(video-assisted thoracic surgery,VATS)解剖性肺段切除术,平均手术时间为153 min,出血量为51 m L。术后漏气10例,均未超过3天。健侧肺不张1例,乳糜胸1例。平均住院时间为6.1天。出院后30天内门诊复查未发生其他院外手术相关并发症。病理为转移瘤者2例,良性肺病8例,原发肺癌25例。25例原发肺癌中浸润性肺腺癌14例[CT以肺磨玻璃影(ground-glass opacity,GGO)为主者7例],微小浸润腺癌4例(GGO为主者3例),原位腺癌6例(CT均为纯GGO),肺鳞癌1例(CT以实性成分为主)。25例肺癌平均切除淋巴结7.2枚,所有淋巴结无癌转移。结论 VATS解剖性肺段切除术技术上安全可靠,其在肺癌治疗中适应症需严格掌握,其优势仍需前瞻性随机对照实验来证实。 展开更多
关键词 腹腔镜 解剖性肺段切除术 肺肿瘤
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紫花苜蓿形态和生理指标响应干旱胁迫的品种特异性 被引量:10
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作者 臧真凤 白婕 +3 位作者 刘丛 昝看卓 龙明秀 何树斌 《草业学报》 CSCD 北大核心 2021年第6期73-81,共9页
为研究紫花苜蓿在叶片和根系水平上响应干旱胁迫的形态和生理的品种特异性规律,在温室内分析了干旱胁迫下WL363HQ和巨能7紫花苜蓿株高、分枝数、生物量及叶片和根系中丙二醛(MDA)、脯氨酸、抗氧化酶类物质、C、N含量、C/N、稳定性C同位... 为研究紫花苜蓿在叶片和根系水平上响应干旱胁迫的形态和生理的品种特异性规律,在温室内分析了干旱胁迫下WL363HQ和巨能7紫花苜蓿株高、分枝数、生物量及叶片和根系中丙二醛(MDA)、脯氨酸、抗氧化酶类物质、C、N含量、C/N、稳定性C同位素(δ^(13)C)和稳定性N同位素(δ^(15)N)。结果表明:干旱胁迫显著降低了供试品种地上部分和根系的干重及分枝数(P<0.05)。干旱胁迫显著降低了巨能7的株高(P<0.05),但增加了巨能7的根冠比,而WL363HQ的结果与之相反,这说明干旱胁迫下供试品种的株高和根冠比具有品种特异性的规律。干旱胁迫增加了WL363HQ和巨能7叶片和根系中MDA和脯氨酸的含量及抗氧化酶物质的活性,且在器官水平也具有品种特异性规律。干旱胁迫下巨能7叶片的MDA含量显著增加(P<0.05),而在WL363HQ根系中的MDA含量也显著增加(P<0.05)。干旱胁迫下WL363HQ叶片脯氨酸含量、POD和SOD活性,及根系SOD的活性均显著增加(P<0.05),而巨能7仅叶片SOD活性,根系脯氨酸含量、POD活性显著升高(P<0.05)。尽管干旱胁迫对供试品种叶片和根系C、N含量无显著影响(P>0.05),但干旱胁迫显著提高了WL363HQ和巨能7紫花苜蓿根系的δ^(13)C(P<0.05),且WL363HQ叶片的δ^(15)N均显著高于巨能7(P<0.05)。此外,干旱胁迫均显著提高了巨能7叶片和根系的C/N(P<0.05)。干旱胁迫下供试品种C、N代谢参数并没有在叶片和根系中表现出较为明显的品种特异性规律,深层次的机制还有待进一步研究。本研究结果将为进一步掌握紫花苜蓿叶片和根系协同抗旱机制及抗旱丰产紫花苜蓿新品种的选育提供理论依据。 展开更多
关键词 紫花苜蓿 干旱胁迫 叶片和根系 品种特异性 丙二醛 脯氨酸 δ^(13)C和δ^(15)N
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生长激素释放肽对糖尿病大鼠视网膜病变的保护作用 被引量:1
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作者 白洁 张锦妹 +3 位作者 刘丽苹 王佳妮 孙雯 杨帆 《国际眼科杂志》 CAS 北大核心 2021年第11期1861-1864,共4页
目的:探讨生长激素释放肽(ghrelin)对糖尿病大鼠视网膜病变的影响并研究其保护作用。方法:雄性SD大鼠18只分为对照组、模型组、ghrelin组,采用HE染色观察视网膜形态,TUNEL染色观察细胞凋亡,透射电镜观察视网膜色素上皮层超微结构,免疫... 目的:探讨生长激素释放肽(ghrelin)对糖尿病大鼠视网膜病变的影响并研究其保护作用。方法:雄性SD大鼠18只分为对照组、模型组、ghrelin组,采用HE染色观察视网膜形态,TUNEL染色观察细胞凋亡,透射电镜观察视网膜色素上皮层超微结构,免疫组化检测氧化应激指标,ELISA检测炎性因子含量。结果:形态学观察结果显示,ghrelin可减轻视网膜组织损伤程度,降低糖尿病大鼠视网膜组织细胞凋亡;免疫组化结果显示,与模型组比较,ghrelin组大鼠视网膜组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)活性升高,丙二醛(MDA)含量下降(P<0.05);ELISA结果显示,模型组细胞间黏附分子-1(ICAM-1)、肿瘤坏死因子-a(TNF-a)及白细胞介素-1β(IL-1β)表达较对照组升高(P<0.05),ghrelin干预后,炎症因子表达均下降,与模型组比较有差异(P<0.05)。结论:Ghrelin治疗糖尿病大鼠后,能有效延缓糖尿病大鼠视网膜病变的进程,其作用机制与降低氧化应激水平、抑制炎症反应相关。 展开更多
关键词 生长激素释放肽 SD大鼠 视网膜 氧化应激 炎症因子
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Complete genome sequence of the rifamycin SV-producing Amycolatopsis mediterranei U32 revealed its genetic characteristics in phylogeny and metabolism 被引量:11
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作者 Wei Zhao Yi Zhong +23 位作者 Hua Yuan Jin Wang Huajun Zheng Ying Wang Xufeng Cen Feng Xu jie bai Xiaobiao Han Gang Lu Yongqiang Zhu Zhihui Shao Han Yan Chen Li Nanqiu Peng Zilong Zhang Yunyi Zhang Wei Lin Yun Fan Zhongjun Qin Yongfei Hu Baoli Zhu Shengyue Wang Xiaoming Ding Guo-Ping Zbao 《Cell Research》 SCIE CAS CSCD 2010年第10期1096-1108,共13页
Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strai... Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strain U32 comprising 10 236 715 base pairs, is one of the largest prokaryotic genomes ever sequenced so far. Unlike the linear topology found in streptomycetes, this chromosome is circular, particularly similar to that of Saccharopolyspora erythraea and Nocardia farcinica, representing their close relationship in phylogeny and taxonomy. Although the predicted 9 228 protein-coding genes in the A. mediterranei genome shared the greatest number of orthologs with those of S. erythraea, it was unexpectedly followed by Streptomyces coelicolor rather than N. farcinica, indicating the distinct metabolic characteristics evolved via adaptation to diverse ecological niches. Besides a core region analogous to that common in streptomycetes, a novel 'quasicore' with typical core characteristics is defined within the non-core region, where 21 out of the total 26 gene clusters for secondary metabolite production are located. The rifamycin biosynthesis gene cluster located in the core encodes a cytochrome P450 enzyme essential for the conversion of rifamycin SV to B, revealed by comparing to the highly homologous cluster of the rifamycin B-producing strain S699 and further confirmed by genetic complementation. The genomic information of A. mediterranei demonstrates a metabolic network orchestrated not only for extensive utilization of various carbon sources and inorganic nitrogen compounds but also for effective funneling of metabolic intermediates into the secondary antibiotic synthesis process under the control of a seemingly complex regulatory mechanism. 展开更多
关键词 GENOME Amycolatopsis mediterranei RIFAMYCIN PHYLOGENY P450 METABOLISM
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Postoperative morbidity adversely impacts oncological prognosis after curative resection for hilar cholangiocarcinoma 被引量:13
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作者 Zhi-Peng Liu Wei-Yue Chen +7 位作者 Yan-Qi Zhang Yan Jiang jie bai Yu Pan Shi-Yun Zhong Yun-Ping Zhong Zhi-Yu Chen Hai-Su Dai 《World Journal of Gastroenterology》 SCIE CAS 2022年第9期948-960,共13页
BACKGROUND Postoperative morbidity after curative resection for hilar cholangiocarcinoma(HCCA)is common;however,whether it has an impact on oncological prognosis is unknown.AIM To evaluate the influence of postoperati... BACKGROUND Postoperative morbidity after curative resection for hilar cholangiocarcinoma(HCCA)is common;however,whether it has an impact on oncological prognosis is unknown.AIM To evaluate the influence of postoperative morbidity on tumor recurrence and mortality after curative resection for HCCA.METHODS Patients with recently diagnosed HCCA who had undergone curative resection between January 2010 and December 2017 at The First Affiliated Hospital of Army Medical University in China were enrolled.The independent risk factors for morbidity in the 30 d after surgery were investigated,and links between postoperative morbidity and patient characteristics and outcomes were assessed.Postoperative morbidities were divided into five grades based on the Clavien-Dindo classification,and major morbidities were defined as Clavien-Dindo≥3.Univariate and multivariate Cox regression analyses were used to evaluate the risk factors for recurrence-free survival(RFS)and overall survival(OS).RESULTS Postoperative morbidity occurred in 146 out of 239 patients(61.1%).Multivariate logistic regression revealed that cirrhosis, intraoperative blood loss > 500 mL, diabetes mellitus,and obesity were independent risk factors. Postoperative morbidity was associated with decreasedOS and RFS (OS: 18.0 mo vs 31.0 mo, respectively, P = 0.003;RFS: 16.0 mo vs 26.0 mo, respectively,P = 0.002). Multivariate Cox regression analysis indicated that postoperative morbidity wasindependently associated with decreased OS [hazard ratios (HR): 1.557, 95% confidence interval(CI): 1.119-2.167, P = 0.009] and RFS (HR: 1.535, 95%CI: 1.117-2.108, P = 0.008). Moreover, majormorbidity was independently associated with decreased OS (HR: 2.175;95%CI: 1.470-3.216, P <0.001) and RFS (HR: 2.054;95%CI: 1.400-3.014, P < 0.001) after curative resection for HCCA.CONCLUSIONPostoperative morbidity (especially major morbidity) may be an independent risk factor forunfavorable prognosis in HCCA patients following curative resection. 展开更多
关键词 Hilar cholangiocarcinoma MORBIDITY Surgery ONCOLOGY SURVIVAL RECURRENCE
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Seasonal and inter-annual variations in carbon fluxes and evapotranspiration over cotton field under drip irrigation with plastic mulch in an arid region of Northwest China 被引量:12
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作者 jie bai Jin WANG +4 位作者 Xi CHEN Ge Ping LUO Hao SHI Long Hui LI Jun Li LI 《Journal of Arid Land》 SCIE CSCD 2015年第2期272-284,共13页
Xinjiang is the largest semi-arid and arid region in China, and drip irrigation under plastic mulch is widely used in this water-limited area. Quantifying carbon and water fluxes as well as investigating their environ... Xinjiang is the largest semi-arid and arid region in China, and drip irrigation under plastic mulch is widely used in this water-limited area. Quantifying carbon and water fluxes as well as investigating their environ- mental drivers over cotton fields is critical for understanding regional carbon and water budgets in Xinjiang, the largest cotton production basin of China. In this study, an eddy covariance (EC) technique was used to measure the carbon and water fluxes of cotton field under drip irrigation with plastic mulch in the growing seasons of 2009, 2010, 2012 and 2013 at Wulanwusu Agrometeorological Experiment Station, a representative oasis cropland in northern Xinjiang. The diurnal patterns of gross primary production (GPP), net ecosystem exchange (NEE) and evapotran-spiration (ET) showed obviously sinusoidal variations from June to September, while the diurnal ecosystem respiration (Res) was stable between daytime and nighttime. The daytime hourly GPP and ET displayed asymptotic rela-tionships with net solar radiation (Rnet), while showed concave patterns with raising vapor pressure deficit (VPD) and air temperature (Ta). The increases in hourly GPP and ET towards the maximum occurred over half ranges of VPD and Ta. The seasonal variations of GPP, NEE and ET were close to the cotton phenology, which almost reached the peak value in July. The cumulative GPP averaged 816.2±55.0 g C/m^2 in the growing season (from April to October), and more than half of GPP was partitioned into NEE (mean value of -478.6±41.4 g C/m^2). The mean seasonal ET was 501.3±13.9 mm, and the mean water use efficiency (WUE) was 1.0+0.1 (mg C/g H2O)/d. The agro-ecosystem behaved as a carbon sink from squaring to harvest period, while it acted as a carbon source before the squaring time as well as after the harvest time. 展开更多
关键词 cotton eddy covariance net ecosystem exchange (NEE) carbon budget water use efficiency (WUE)
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Effect of Bacillus amyloliquefaciens and Bacillus subtilis on fermentation, dynamics of bacterial community and their functional shifts of whole-plant corn silage 被引量:11
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作者 jie bai Marcia Franco +8 位作者 Zitong Ding Lin Hao Wencan Ke Musen Wang Dongmei Xie Ziqian Li Yixin Zhang Lin Ai Xusheng Guo 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第3期864-877,共14页
Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals.However,few research have reported the effects of... Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals.However,few research have reported the effects of BA and BS on fermentation characteristics and bacterial community successions of whole-plant corn silage during ensiling.If the BA and BS inoculants have positive effects on silages,then they could not only improve fermentation characteristics,but also deliver BA or BS viable cells to ruminants,which would play its probiotic effect.Therefore,the objectives of this study were to investigate the effects of BA and BS on the fermentation,chemical characteristics,bacterial community and their metabolic pathway of whole-plant corn silage.Results:Freshly chopped whole-plant corn was inoculated without or with BA and BS,respectively,and ensiled for1,3,7,14 and 60 d.Results showed that BA and BS inoculations increased lactic acid concentrations of whole-plant corn silages compared with control,and BA inoculation decreased acetic acid concentrations,whereas BS inoculation decreased fiber contents and increased crude protein(CP)content.Higher water-soluble carbohydrate contents and lower starch contents were observed in BA-and BS-inoculated silages compared with that in control.The decreased CP content and increased non-protein nitrogen content were observed in BA-inoculated silage,which was consistent with the higher amino acid metabolism abundances observed in BA-inoculated silage.In addition,it was noteworthy that BA and BS inoculations increased the metabolism of cofactors and vitamins,and decreased the relative abundances of drug resistance:antimicrobial pathways.We also found that the bacterial metabolism pathways were clearly separated into three clusters based on the ensiling times of whole-plant corn silage in the present study.There were no significant differences in bacterial community compositions among the three groups during ensiling.However,BA and BS inoculations decreased the relative abundances of undesirable bacteria such as Acetobacter and Acinetobacter.Conclusion:Our findings suggested that the BS strain was more suitable as silage inoculants than the BA strain in whole-plant corn silage in this study. 展开更多
关键词 Bacillus silage inoculants Function prediction Silage quality Zea mays
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Protective effect of heme oxygenase-1 on Wistar rats with heart failure through the inhibition of inflammation and amelioration of intestinal micro- circulation 被引量:11
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作者 Li ZHANG Zhuo-Kun GAN +9 位作者 Li-Na HAN Hao WANG jie bai Guo-Juan TAN Xiao-Xia LI Ya-Ping XU Yu ZHOU Mei-Liang GONG Mo-Si LIN Xiao-Yang HAN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2015年第4期353-365,共13页
Background Myocardial infarction (MI) has likely contributed to the increased prevalence of heart failure (HF). As a result of re- duced cardiac function, splanchnic blood flow decreases, causing ischemia in villi... Background Myocardial infarction (MI) has likely contributed to the increased prevalence of heart failure (HF). As a result of re- duced cardiac function, splanchnic blood flow decreases, causing ischemia in villi and damage to the intestinal barrier. The induction of heme oxygenase-1 (HO-1) could prevent, or lessen the effects of stress and inflammation. Thus, the effect and mechanism thereof of HO-1 on the intestines of rats with HF was investigated. Methods Male Wistar rats with heart failure through ligation of the left coronary artery were identified with an left ventricular ejection fraction of 〈 45% through echocardiography and then divided into various experimental groups based on the type of peritoneal injection they received [MI: saline; MI + Cobalt protoporphyrin (CoPP): CoPP solution; and MI + Tin mesoporphyrin IX dichloride (SnMP): SnMP solution]. The control group was comprised of rats without coronary ligation. Echocardiogra- phy was performed before ligation for a baseline and eight weeks after ligation in order to evaluate the cardiac function of the rats. The bac- terial translocation (BT) incidence, mesenteric microcirculation, amount of endotoxins in the vein serum, ileum levels of HO- 1, carbon oxide (CO), nitric oxide (NO), intedeuldn (IL)-10, turnour necrosis factor-et (TNF-ct), and the ileum morphology were determined eight weeks after the operation. Results The rats receiving MI + CoPP injections exhibited a recovery in cardiac function, an amelioration of mesenteric microcirculation and change in morphology, a lower BT incidence, a reduction in serum and ileac NO and TNF-ct levels, and an elevation in ileac HO-1, CO, and interleukin-10 ([L-10) levels compared to the MI group (P 〈 0.05). The rats that received the MI + SnMP injections exhibited results inverse to the MI (P 〈 0.05) group. Conclusions HO-1 exerted a protective effect on the intestines of rats with HF by inhibiting the inflammation and amelioration of microcirculation through the CO pathway. This protective effect could be independent from the recovery of cardiac function. 展开更多
关键词 Carbon monoxide Heart failure Heme oxygenase-1 INTESTINE
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重复经颅磁刺激治疗抑郁症的机制研究进展(英文) 被引量:15
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作者 Zhengwu PENG Cuihong ZHOU +5 位作者 Shanshan XUE jie bai Shoufen YU Xiaosa LI Huaning WANG Qingrong TAN 《上海精神医学》 CSCD 2018年第2期84-92,共9页
概述:抑郁障碍是目前最常见的心理健康问题之一。然而,对于该疾病的基于机制的治疗方法仍然是难以捉摸的。重复经颅磁刺激(rTMS)是一种非侵入性的程序,它可以以一种脉冲磁场来刺激大脑中的电活动,被认为是一种有效的抑郁症治疗方式。在... 概述:抑郁障碍是目前最常见的心理健康问题之一。然而,对于该疾病的基于机制的治疗方法仍然是难以捉摸的。重复经颅磁刺激(rTMS)是一种非侵入性的程序,它可以以一种脉冲磁场来刺激大脑中的电活动,被认为是一种有效的抑郁症治疗方式。在这里,我们回顾了关于rTMS治疗抑郁症的临床和基础研究的主要发现,包括它的抗抑郁疗效,基本原理,调节神经回路、神经递质和脑网络、海马神经发生、和突出的功效,以及分子通路。 展开更多
关键词 机制 磁性 心理健康问题 神经发生 RTMS 调查结果 抗抑郁剂 大脑
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