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F-FDG-PET glucose hypometabolism pattern in patients with epileptogenic hypothalamic hamartoma

《医学前沿（英文）》 2021年 第15卷 第6期   页码 913-921 doi: 10.1007/s11684-021-0874-1

摘要： Epileptogenic hypothalamic hamartoma is characterized by intractable gelastic seizures. A systematic analysis of the overall brain metabolic pattern in patients with hypothalamic hamartoma (HH) could facilitate the understanding of the epileptic brain network and the associated brain damage effects of HH. In this study, we retrospectively evaluated 27 patients with epileptogenic HH (8 female patients; age, 2–33 years) by using 18F-fluorodeoxyglucose-positron emission tomography. The correlations among tomography result, seizure type, sex, and structural magnetic resonance imaging were assessed. Whole metabolic patterns and voxel-based morphometry findings were assessed by group analysis with healthy controls. Assessment of the whole metabolic pattern in patients with HH revealed several regional metabolic reductions in the cerebrum and an overall metabolic reduction in the cerebellum. In addition, areas showing hypometabolism in the neocortex were more widely distributed ipsilaterally than contralaterally to the HH. Reductions in glucose metabolism and gray matter volume in the neocortex were predominant ipsilateral to the HH. In conclusion, the glucose hypometabolism pattern in patients with epileptogenic HH involved the neocortex, subcortical regions, and cerebellum. The characteristics of glucose hypometabolism differed across seizure type and sex. Reductions in glucose metabolism and structural changes may be based on different mechanisms, but both are likely to occur ipsilateral to the HH in the neocortex. We hypothesized that the dentato-rubro-thalamic tract and cerebro-ponto-cerebellar tract, which are responsible for intercommunication between the cerebral cortex, subcortical regions, and cerebellar regions, may be involved in a pathway related to seizure propagation, particularly gelastic seizures, in patients with HH.

关键词： hypothalamic hamartoma     gelastic seizure     fluorodeoxyglucose-positron emission tomography     voxel-based morphometry    

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Quantitative proteomics revealed extensive microenvironmental changes after stem cell transplantation in ischemic stroke

《医学前沿（英文）》 2022年 第16卷 第3期   页码 429-441 doi: 10.1007/s11684-021-0842-9

摘要： The local microenvironment is essential to stem cell-based therapy for ischemic stroke, and spatiotemporal changes of the microenvironment in the pathological process provide vital clues for understanding the therapeutic mechanisms. However, relevant studies on microenvironmental changes were mainly confined in the acute phase of stroke, and long-term changes remain unclear. This study aimed to investigate the microenvironmental changes in the subacute and chronic phases of ischemic stroke after stem cell transplantation. Herein, induced pluripotent stem cells (iPSCs) and neural stem cells (NSCs) were transplanted into the ischemic brain established by middle cerebral artery occlusion surgery. Positron emission tomography imaging and neurological tests were applied to evaluate the metabolic and neurofunctional alterations of rats transplanted with stem cells. Quantitative proteomics was employed to investigate the protein expression profiles in iPSCs-transplanted brain in the subacute and chronic phases of stroke. Compared with NSCs-transplanted rats, significantly increased glucose metabolism and neurofunctional scores were observed in iPSCs-transplanted rats. Subsequent proteomic data of iPSCs-transplanted rats identified a total of 39 differentially expressed proteins in the subacute and chronic phases, which are involved in various ischemic stroke-related biological processes, including neuronal survival, axonal remodeling, antioxidative stress, and mitochondrial function restoration. Taken together, our study indicated that iPSCs have a positive therapeutic effect in ischemic stroke and emphasized the wide-ranging microenvironmental changes in the subacute and chronic phases.

关键词： ischemic stroke     microenvironment     induced pluripotent stem cells (iPSCs)     positron emission tomography (PET)     quantitative proteomics    

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局部高空间分辨率的应用适应性PET系统设计初探

刘晶晶,谢庆国

《中国工程科学》 2011年 第13卷 第10期   页码 105-112

摘要：

研制成本可负担的高空间分辨率正电子发射断层成像（positron emission tomography，PET）系统在PET成像应用中具有决定性的意义，也是PET成像面临的关键性挑战之一。设想一种PET系统，能够根据应用的需求对不同性能的探测器进行布局，在一个具体时刻，对部分成像区域获得很高的性能，而在其他的区域获得普通性能。提出了一种应用适应性PET系统原型，由大部分普通固有空间分辨率的探测模块和少量更高甚至极端高固有空间分辨率的探测模块组成。研究了在含有连续放置的一段高固有空间分辨率探测模块的PET系统中，高性能模块的布局位置和数量对视场内不同位置点的空间分辨率的影响。

关键词： 正电子发射断层成像     应用适应性PET系统     感兴趣区域     局部空间分辨率     不同性能探测模块    

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Philadelphia chromosome-positive acute myeloid leukemia with masses and osteolytic lesions: finding of 18F-FDG PET

null

《医学前沿（英文）》 2017年 第11卷 第3期   页码 440-444 doi: 10.1007/s11684-017-0523-x

摘要：

Philadelphia chromosome-positive acute myeloid leukemia is controversial and difficult to distinguish from the blast phase of chronic myeloid leukemia. As a myeloid neoplasm, rare cases of this leukemia manifest multiple soft-tissue tumors or bone lytic lesions. In this paper, we describe a 49-year-old male patient who had an abrupt onset with sharp chest pain, fever, fatigue, emaciation, and splenomegaly. 18F-fluoro-deoxy-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) result showed diffuse and uneven hypermetabolic lesions in the bone marrow with peripheral bone marrow expansion, multiple soft tissue neoplasms with high 18F-FDG uptake, and lytic bone lesions. Bone marrow smear and biopsy detected aberrant blast cells expressing myeloid rather than lymphoid immunophenotype marker. For the existence of Philadelphia chromosome and BCR-ABL1 fusion gene together with complex chromosome abnormalities, a diagnosis of Philadelphia-positive acute myeloid leukemia was made, although the type (de novo or blast crisis) remained unclear.

关键词： Philadelphia chromosome     acute myeloid leukemia     mass     osteolysis     positron emission tomography    

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PET imaging on neurofunctional changes after optogenetic stimulation in a rat model of panic disorder

Xiao He, Chentao Jin, Mindi Ma, Rui Zhou, Shuang Wu, Haoying Huang, Yuting Li, Qiaozhen Chen, Mingrong Zhang, Hong Zhang, Mei Tian

《医学前沿（英文）》 2019年 第13卷 第5期   页码 602-609 doi: 10.1007/s11684-019-0704-x

摘要： Panic disorder (PD) is an acute paroxysmal anxiety disorder with poorly understood pathophysiology. The dorsal periaqueductal gray (dPAG) is involved in the genesis of PD. However, the downstream neurofunctional changes of the dPAG during panic attacks have yet to be evaluated . In this study, optogenetic stimulation to the dPAG was performed to induce panic-like behaviors, and positron emission tomography (PET) imaging with F-flurodeoxyglucose ( F-FDG) was conducted to evaluate neurofunctional changes before and after the optogenetic stimulation. Compared with the baseline, post-optogenetic stimulation PET imaging demonstrated that the glucose metabolism significantly increased ( <0.001) in dPAG, the cuneiform nucleus, the cerebellar lobule, the cingulate cortex, the alveus of the hippocampus, the primary visual cortex, the septohypothalamic nucleus, and the retrosplenial granular cortex but significantly decreased ( <0.001) in the basal ganglia, the frontal cortex, the forceps minor corpus callosum, the primary somatosensory cortex, the primary motor cortex, the secondary visual cortex, and the dorsal lateral geniculate nucleus. Taken together, these data indicated that PET imaging can successfully detect downstream neurofunctional changes involved in the panic attacks after optogenetic stimulation to the dPAG.

关键词： panic disorder (PD)     positron emission tomography (PET)     optogenetics     dorsal periaqueductal gray (dPAG)    

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用于医学诊断和治疗的质子回旋加速器

樊明武

《中国工程科学》 2000年 第2卷 第12期   页码 9-15

摘要：

在许多医院都安装了生产短寿命放射性同位素的回旋加速器，但用于质子治疗的回旋加速器还处于起步阶段。质子治疗可以达到精确的幅照剂量分布，质子能量决定了穿透深度，因而产生的能量释放点可以精确控制，技术先进。由于质子束传播的线形度好，引起的横向二次散射小，肿瘤前端的健康组织接受的剂量很小，在其周围和之后的组织几乎就没有照射剂量，因此质子束治疗是一种非常有效的方法。束流传输到治疗房间的效率，束流的能量控制、强度及位置的稳定性，快速而精确的改变束流参数来满足临床需要等，都是关键。开发安装于医院的并可满足病人实际需要的质子治疗回旋加速器，包括束流输运系统和一系列的控制系统都相当复杂，文章提出了用于该目的的概念框图和建议。

关键词： 回旋加速器     正电子断层照相     短寿命放射性同位素     质子束治疗    

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功能影像检测食管癌放疗过程中再增殖和乏氧以及预测临床疗效研究

于金明

《中国工程科学》 2012年 第14卷 第7期   页码 9-19

摘要：

18F-FLT PET能监测食管鳞癌放疗过程中肿瘤和正常组织的生物学变化，其较18F-FDG PET能较好区分炎症和肿瘤，能检测食管肿瘤放疗过程中的加速再增殖,18F-FETNIM PET能检测食管鳞癌的乏氧状态,18F-FLT PET和18F-FETNIM PET作为一种非创伤性的影像学技术，能为肿瘤医生提供一个早期评价治疗反应，检测放疗过程中的再增殖克隆源细胞18F-FLT PET和18F-FETNIM PET能为放射治疗确定“再增殖”和“乏氧”生物学靶区，以通过剂量调强放疗提高再增殖和乏氧区域放疗剂量，提高肿瘤的局部控制率和远期生存

关键词： 食管肿瘤     放射疗法     正电子发射型     再增殖     乏氧    

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Resveratrol promotes the survival and neuronal differentiation of hypoxia-conditioned neuronal progenitor cells in rats with cerebral ischemia

Yao Yao, Rui Zhou, Rui Bai, Jing Wang, Mengjiao Tu, Jingjing Shi, Xiao He, Jinyun Zhou, Liu Feng, Yuanxue Gao, Fahuan Song, Feng Lan, Xingguo Liu, Mei Tian, Hong Zhang

《医学前沿（英文）》 2021年 第15卷 第3期   页码 472-485 doi: 10.1007/s11684-021-0832-y

摘要： Hypoxia conditioning could increase the survival of transplanted neuronal progenitor cells (NPCs) in rats with cerebral ischemia but could also hinder neuronal differentiation partly by suppressing mitochondrial metabolism. In this work, the mitochondrial metabolism of hypoxia-conditioned NPCs (hcNPCs) was upregulated via the additional administration of resveratrol, an herbal compound, to resolve the limitation of hypoxia conditioning on neuronal differentiation. Resveratrol was first applied during the neuronal differentiation of hcNPCs and concurrently promoted the differentiation, synaptogenesis, and functional development of neurons derived from hcNPCs and restored the mitochondrial metabolism. Furthermore, this herbal compound was used as an adjuvant during hcNPC transplantation in a photothrombotic stroke rat model. Resveratrol promoted neuronal differentiation and increased the long-term survival of transplanted hcNPCs. 18-fluorine fluorodeoxyglucose positron emission tomography and rotarod test showed that resveratrol and hcNPC transplantation synergistically improved the neurological and metabolic recovery of stroke rats. In conclusion, resveratrol promoted the neuronal differentiation and therapeutic efficiency of hcNPCs in stroke rats via restoring mitochondrial metabolism. This work suggested a novel approach to promote the clinical translation of NPC transplantation therapy.

关键词： neuronal progenitor cells     resveratrol     cerebral ischemia     neuronal differentiation     mitochondrial metabolism     positron emission tomography    

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通过蛋白质工程提高聚酯水解酶对PET 塑料的降解效率 Article

马渊, 姚明东, 李炳志, 丁明珠, 何博, 陈思, 周晓, 元英进

《工程（英文）》 2018年 第4卷 第6期   页码 888-893 doi: 10.1016/j.eng.2018.09.007

摘要：

来自Ideonella sakaiensis 的聚对苯二甲酸乙二醇酯水解酶（PETase）在室温下具有很强的降解聚对苯二甲酸乙二醇酯（PET）的能力，因此被认为是解决聚酯塑料污染问题的潜在工具在本研究中，基于PETase 和底物2PET 结合时的相互作用模型，分析了PETase 与底物2PET 之间的相互作用，从而对底物结合沟壑周围的六个关键残基进行改造。

关键词： 聚酯酶     PET降解     无细胞蛋白质合成     聚酯     PET酶    

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Experimental investigations of internal energy dissipation during fracture of fiber-reinforced ultra-high-performance concrete

Eric N. LANDIS, Roman KRAVCHUK, Dmitry LOSHKOV

《结构与土木工程前沿（英文）》 2019年 第13卷 第1期   页码 190-200 doi: 10.1007/s11709-018-0487-1

摘要： Split-cylinder fracture of fiber-reinforced ultra-high-performance concrete (UHPC) was examined using two complementary techniques: X-ray computed tomography (CT) and acoustic emission (AE). Fifty-mm-diameter specimens of two different fiber types were scanned both before and after load testing. From the CT images, fiber orientation was evaluated to establish optimum and pessimum specimen orientations, at which fibers would have maximum and minimum effect, respectively. As expected, fiber orientation affected both the peak load and the toughness of the specimen, with the optimum toughness being between 20% and 30% higher than the pessimum. Cumulative AE energy was also affected commensurately. Posttest CT scans of the specimens were used to measure internal damage. Damage was quantified in terms of internal energy dissipation due to both matrix cracking and fiber pullout by using calibration measurements for each. The results showed that fiber pullout was the dominant energy dissipation mechanism; however, the sum of the internal energy dissipation measured amounted to only 60% of the total energy dissipated by the specimens as measured by the net work of load. It is postulated that localized compaction of the UHPC matrix as well as internal friction between fractured fragments makes up the balance of internal energy dissipation.

关键词： ultra-high-performance concrete     concrete fracture     X-ray computed tomography     acoustic emission    

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Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations

Zhonghua Sun

《医学前沿（英文）》 2011年 第5卷 第3期   页码 254-270 doi: 10.1007/s11684-011-0153-7

摘要： Multislice computed tomography (CT) has been widely used in clinical practice for the diagnosis of cardiovascular disease due to its reduced invasiveness and high spatial and temporal resolution. As a reliable alternative to conventional angiography, multislice CT angiography has been recognized as the method of choice for detecting and diagnosing head and neck vascular disease, abdominal aortic aneurysm, aortic dissection, and pulmonary embolism. In patients with suspected coronary artery disease, although invasive coronary angiography still remains as the gold standard technique, multislice CT angiography demonstrates high diagnostic accuracy; in selected patients, it is considered as the first-line technique. The imaging diagnosis of cardiovascular disease is based on a combination of two-dimensional (2D) and three-dimensional (3D) visualization tools to enhance the diagnostic value. This is facilitated by reconstructed visualizations which provide additional information about the extent of the disease, an accurate assessment of the spatial relationship between normal structures and pathological changes, and pre-operative planning and post-procedure follow-up. The aim of the present article is to present an overview of the diagnostic performance of various 2D and 3D CT visualizations in cardiovascular disease, including multiplanar reformation, maximum intensity projection, volume rendering, and virtual intravascular endoscopy. The recognition of the potential value of these visualizations will assist clinicians in efficiently using the multislice CT imaging modality for the diagnostic management of patients with cardiovascular disease.

关键词： cardiovascular disease     multislice computed tomography     three-dimensional reconstruction     diagnosis     visualization    

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4-Amino-1,8-naphthalimide based fluorescent photoinduced electron transfer (PET) pH sensors as liposomalcellular imaging agents: The effect of substituent patterns on PET directional quenching

Miguel Martínez-Calvo, Sandra A. Bright, Emma B. Veale, Adam F. Henwood, D. Clive Williams, Thorfinnur Gunnlaugsson

《化学科学与工程前沿（英文）》 2020年 第14卷 第1期   页码 61-75 doi: 10.1007/s11705-019-1862-8

摘要： Four new fluorescent sensors ( - ) based on the 4-amino-1,8-naphthalimide fluorophores ( ) have been synthesized based on the classical fluorophore-spacer-receptor model. These four compounds all gave rise to emission bands centred at 535 nm, which were found to be highly pH dependent, the emission being ‘switched on’ in acidic media, while being quenched due to PET from the amino moieties to the excited state of the at more alkaline pH. The luminescent pH dependence for these probes was found to be highly dependent on the substitution on the imide site, as well as the polyamine chain attached to the position 4-amino moiety. In the case of sensor the presence of the 4-amino-aniline dominated the pH dependent quenching. Nevertheless, at higher pH, PET quenching was also found to occur from the polyamine site. Hence, is better described as a receptor -spacer -fluorophore-spacer -receptor system, where the dominant PET process is due to (normally less favourable) ‘directional’ PET quenching from the 4-amino-aniline unit to the site. Similar trends and pH fluorescence dependences were also seen for and . These compounds were also tested for their imaging potential and toxicity against HeLa cells (using DRAQ5 as nuclear stain which does now show pH dependent changes in acidic and neutral pH) and the results demonstrated that these compounds have reduced cellular viability at moderately high concentrations (with IC values between ca. 8‒30 µmol∙L ), but were found to be suitable for intracellular pH determination at 1 µmol∙L concentrations, where no real toxicity was observed. This allowed us to employ these as lysosomal probes at sub-toxic concentrations, where the based emission was found to be pH depended, mirroring that seen in aqueous solution for , with the main fluorescence changes occurring within acidic to neutral pH.

关键词： sensors     pH     photoinduced electron transfer     cellular imaging     confocal microscopy    

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Solubility of CO in solid-state PET measured by pressure-decay method

CHEN Miaocan, ZHAO Ling, LIU Tao, WU Jiangwei, YUAN Weikang

《化学科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 214-219 doi: 10.1007/s11705-008-0040-1

摘要： The solubility of CO in solid-state PET was measured using a pressure-decay method. In order to calculate the solubility of CO in the amorphous region of PET, the crystallinity of solid state PET dissolved in CO at different pressures and temperatures was measured by differential scanning calorimetry (DSC). The solubility increases with increasing pressure and it follows a linear relationship and obeys Henry’s law when the pressure is below 8 MPa. The effect of temperature on solubility is weak and the solubilities at different temperatures are almost the same under low pressures. At higher pressure, the solubility decreases with an increase in temperature. The solubility of CO in the amorphous region of PET at 373.15 K, 398.15 K and 423.15 K was correlated with the Sanchez-Lacombe equation of state with a maximal correlation error of 6.69%.

关键词： Sanchez-Lacombe equation     solid-state PET     different     relationship     calorimetry    

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Laser sintering of Cu nanoparticles on PET polymer substrate for printed electronics at different wavelengths

Juan Carlos HERNANDEZ-CASTANEDA, Boon Keng LOK, Hongyu ZHENG

《机械工程前沿（英文）》 2020年 第15卷 第2期   页码 303-318 doi: 10.1007/s11465-019-0562-x

摘要： This study explores the feasibility of different laser systems to sinter screen-printed lines from nonconductive copper nanoparticles (Cu NPs) on polyethylene terephthalate polymer film. These materials are commonly used in manufacturing functional printed electronics for large-area applications. Here, optical and thermal characterization of the materials is conducted to identify suitable laser sources and process conditions. Direct diode (808 nm), Nd:YAG (1064 nm and second harmonic of 532 nm), and ytterbium fiber (1070 nm) lasers are explored. Optimal parameters for sintering the Cu NPs are identified for each laser system, which targets low resistivity and high processing speed. Finally, the quality of the sintered tracks is quantified, and the laser sintering mechanisms observed under different wavelengths are analyzed. Practical considerations are discussed to improve the laser sintering process of Cu NPs.

关键词： laser sintering     copper nanoparticles     printed electronics    

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Erratum to: On secondary new particle formation in China

Markku KULMAMA,Tuukka Petäjä,Veli-Matti KERMINEN,Joni KUJANSUU,Taina RUUSKANEN,Aijun DING,Wei NIE,Min

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0857-7

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标题 作者 时间 类型 操作

F-FDG-PET glucose hypometabolism pattern in patients with epileptogenic hypothalamic hamartoma

期刊论文

Quantitative proteomics revealed extensive microenvironmental changes after stem cell transplantation in ischemic stroke

期刊论文

局部高空间分辨率的应用适应性PET系统设计初探

刘晶晶,谢庆国

期刊论文

Philadelphia chromosome-positive acute myeloid leukemia with masses and osteolytic lesions: finding of 18F-FDG PET

null

期刊论文

PET imaging on neurofunctional changes after optogenetic stimulation in a rat model of panic disorder

Xiao He, Chentao Jin, Mindi Ma, Rui Zhou, Shuang Wu, Haoying Huang, Yuting Li, Qiaozhen Chen, Mingrong Zhang, Hong Zhang, Mei Tian

期刊论文

用于医学诊断和治疗的质子回旋加速器

樊明武

期刊论文

功能影像检测食管癌放疗过程中再增殖和乏氧以及预测临床疗效研究

于金明

期刊论文

Resveratrol promotes the survival and neuronal differentiation of hypoxia-conditioned neuronal progenitor cells in rats with cerebral ischemia

Yao Yao, Rui Zhou, Rui Bai, Jing Wang, Mengjiao Tu, Jingjing Shi, Xiao He, Jinyun Zhou, Liu Feng, Yuanxue Gao, Fahuan Song, Feng Lan, Xingguo Liu, Mei Tian, Hong Zhang

期刊论文

通过蛋白质工程提高聚酯水解酶对PET 塑料的降解效率

马渊, 姚明东, 李炳志, 丁明珠, 何博, 陈思, 周晓, 元英进

期刊论文

Experimental investigations of internal energy dissipation during fracture of fiber-reinforced ultra-high-performance concrete

Eric N. LANDIS, Roman KRAVCHUK, Dmitry LOSHKOV

期刊论文

Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations

Zhonghua Sun

期刊论文

4-Amino-1,8-naphthalimide based fluorescent photoinduced electron transfer (PET) pH sensors as liposomalcellular imaging agents: The effect of substituent patterns on PET directional quenching

Miguel Martínez-Calvo, Sandra A. Bright, Emma B. Veale, Adam F. Henwood, D. Clive Williams, Thorfinnur Gunnlaugsson

期刊论文

Solubility of CO in solid-state PET measured by pressure-decay method

CHEN Miaocan, ZHAO Ling, LIU Tao, WU Jiangwei, YUAN Weikang

期刊论文

Laser sintering of Cu nanoparticles on PET polymer substrate for printed electronics at different wavelengths

Juan Carlos HERNANDEZ-CASTANEDA, Boon Keng LOK, Hongyu ZHENG

期刊论文

Erratum to: On secondary new particle formation in China

Markku KULMAMA,Tuukka Petäjä,Veli-Matti KERMINEN,Joni KUJANSUU,Taina RUUSKANEN,Aijun DING,Wei NIE,Min

期刊论文