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产权认知及外部环境对农户土地流转行为影响模型分析

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农业工程学报 2017年第5期33卷 248-256页

作者：高佳宋戈东北大学文法学院沈阳110169

农民的产权认知及外部环境直接影响农户的土地流转行为决策。该文基于陕西关中地区545户农户调研数据,按农民非农收入水平和承包地经营规模分异将农户进行分组,用多群组结构方程模型,将非农水平和承包地经营规模作为调节变量,分析农户... 详细信息

农民的产权认知及外部环境直接影响农户的土地流转行为决策。该文基于陕西关中地区545户农户调研数据,按农民非农收入水平和承包地经营规模分异将农户进行分组,用多群组结构方程模型,将非农水平和承包地经营规模作为调节变量,分析农户产权认知及外部环境对其土地流转行为的影响差异。研究结果表明:农户土地流转意愿对其土地流转行为的综合影响最大,外部环境次之。农户对土地抵押权的认知对土地流转意愿具有显著影响。家庭非农收入水平高、经营规模小的农户更容易将土地流转意愿转化为土地流转行为。研究产权认知和外部环境因素能为制定土地流转政策提供科学依据。

关键词：土地利用农场模型土地管理城镇化产权认知外部环境土地流转多群组结构方程

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稻属多倍体的研究历史及存在问题

植物分类学报 2008年第1期46卷 3-12页

作者：包颖葛颂曲阜师范大学生命科学学院曲阜273165 系统与进化植物学国家重点实验室中国科学院植物研究所北京100093

稻属Oryza隶属于禾本科Poaceae稻亚科Oryzoideae稻族Oryzeae,包括20多个种,其中近1/2的种类为异源多倍体植物。这些多倍体不但数量多而且涉及BC、CD、HJ和HK等多种染色体组构成,广泛分布于热带亚洲、非洲、大洋洲和拉丁美洲。由于具有... 详细信息

稻属Oryza隶属于禾本科Poaceae稻亚科Oryzoideae稻族Oryzeae,包括20多个种,其中近1/2的种类为异源多倍体植物。这些多倍体不但数量多而且涉及BC、CD、HJ和HK等多种染色体组构成,广泛分布于热带亚洲、非洲、大洋洲和拉丁美洲。由于具有重要的经济和理论研究价值,稻属植物一直在植物学研究中备受瞩目。相应地,稻属多倍体植物的研究也积累了丰富的资料。本文通过回顾以往对稻属植物的研究历史,特别关注有关多倍体的研究,结合我们最近的研究总结了稻属多倍体分类和系统发育关系研究的最新进展,同时对稻属多倍体研究中存在的问题及未来研究方向进行了讨论。

关键词：稻属多倍体历史回顾存在问题

A biomimetic antitumor nanovaccine based on biocompatible calcium pyrophosphate and tumor cell membrane antigens

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Asian Journal of Pharmaceutical Sciences 2021年第1期16卷 97-109页

作者： Minghui Li Mengmeng Qin ge song Hailiang Deng Dakuan Wang Xueqing Wang Wenbing Dai Bing He Hua Zhang Qiang Zhang Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking UniversityBeijing 100191China

Currently,the cancer immunotherapy has made great progress while antitumor vaccine attracts substantial ***,the selection of adjuvants as well as antigens are always the most crucial issues for better *** this study,we proposed a biomimetic antitumor nanovaccine based on biocompatible nanocarriers and tumor cell membrane ***,endogenous calcium pyrophosphate nanogranules with possible immune potentiating effect are designed and engineered,both as delivery vehicles and ***,these nanocarriers are coated with lipids and B16-OVA tumor cell membranes,so the biomembrane proteins can serve as tumor-specific *** was found that calcium pyrophosphate nanogranules themselves were compatible and possessed adjuvant effect,while membrane proteins including tumor associated antigen were transferred onto the *** was demonstrated that such a biomimetic nanovaccine could be well endocytosed by dendritic cells,promote their maturation and antigen-presentation,facilitate lymph retention,and trigger obvious immune *** was confirmed that the biomimetic vaccine could induce strong T-cell response,exhibit excellent tumor therapy and prophylactic effects,and simultaneously possess nice *** general,the present investigation might provide insights for the further design and application of antitumor vaccines.

关键词： Biomimetic nanovaccine Calcium pyrophosphate Membrane antigens Tumor immunotherapy Adjuvant

Protective effect of cyclophilin A against Alzheimer＇s amyloid beta-peptide （25-35）-induced oxidative stress in PC12 cells

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Chinese Medical Journal 2009年第6期122卷 716-724页

作者： ge Yu-song TENG Wei-yu ZHANG Chao-dong Department of Neurology First Affiliated Hospital China Medical University Shenyang Liaoning 110001 China

Background β-amyloid peptide （Aβ） is considered responsible for the pathogenesis of Alzheimer＇s disease （AD）. Possible mechanisms underlying Aβ-induced neuronal cytotoxicity include excessive production of reactive oxidative species （ROS） and apoptosis. Cyclophilin A （CypA）, exhibits antioxidant properties and protects neurons against oxidative stress induced injury. This study was conducted to demonstrate whether CyPA added to cultured PC12 cells could alleviate Aβ-induced oxidative stress and protect them from apoptosis.Methods PC12 cells were pre-incubated for 30 minutes with recombinant human cyclophilin A （rhCyPA） in 0.1 nmol/L, 1.0 nmol/L, 10 nmol/L and 100 nmol/L and then incubated with 10 μmol/L Aβ25-35. In every group, cell viability, apoptotic morphology, apoptotic rate, intracellular ROS accumulation, the activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px） of PC12 cells and mitochondrial transmembrane potential were detected. Subsequently, the expression of the active form of caspase-3 was determined by Western blotting.Results It was shown that cultures treated with 1.0 nmol/L, 1U nmol/L or 100 nmol/L rnL, rhCyPA＋Aβ25-35 had significantly higher cell viability and a lower rate of apoptosis compared with the cultures exposed only to Aβ25-35. In addition, rhCyPA attenuated Aβ25-35-induced overproduction of intracellular ROS and Aβ25.35-induced a decrease in activity of the key antioxidant enzymes SOD and GSH-Px. Furthermore, rhCyPA also attenuated Aβ25.35-induced mitochondrial dysfunction and the activation of caspase-3.Conclusion CyPA may act as an ROS scavenger, and prevent Aβ25-35-induced neurotoxicity through attenuating oxidative stress induced by Aβ25-35.

关键词： Alzheimer's disease cyclophilin A β-amyloid oxidative stress apoptosis

Clinical efficacy of 595-nm pulsed-dye laser in treatment of childhood facial spider nevi: a retrospective study of 110 patients

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Chinese Medical Journal 2019年第20期132卷 2417-2422页

作者： Cheng Zhang Hong-song ge Sen Yang Xue-Jun Zhang Department of Dermatology The First Affiliated Hospital of Anhui Medical UniversityThe Key Laboratory of Dermatology(Anhui Medical University)Ministry of EducationThe Key Laboratory of Major Autoimmune DiseasesHefeiAnhui 230022China Department of Dermatology Anhui Provincial Children’s HospitalHefeiAnhui 230051China

Background:Spider nevi (SN) are quite common in children. SN are treated via different techniques, and complete removal often requires multiple treatments. However, few studies have evaluated the treatment of SN. The present study aimed to evaluate the therapeutic effect and safety of a 595-nm pulsed-dye laser (PDL) for treating facial SN in ***:A total of 110 children aged 0.2 to 12 years with facial SN were treated with a 595-nm PDL in a single institution from January 2016 to February 2018. In accordance with the treatment method, the patients were retrospectively divided into the small-spot-combined-with-large-spot group (SL-group) and the large-spot group (L-group). Patients with poor therapeutic results were retreated every 6 weeks until the lesions disappeared. The minimum follow-up period was 1 year. The groups were compared using independent-samples t tests, Mann-Whitney U test, Chi-square test, and Fisher exact probability ***:The therapeutic efficacy was significantly higher in the SL-group than in the L-group, with clearance rates of 90.9% and 53.0% after the primary treatment, respectively (χ2= 17.937, P ge-spot method is especially suitable for SN with a central spider body diameter ≥1 mm.

关键词： Lasers Telangiectasis Child Spider nevi

Eustachian tube teratoma: A case report

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World Journal of Clinical Cases 2022年第1期10卷 316-322页

作者： Jin-Ye Li Li-Xin Sun Na Hu ge-Sheng song Wei-Qiang Dou Ruo-Zhen Gong Chuan-Ting Li Department of Radiology Shandong Provincial ENT HospitalCheeloo College of MedicineShandong UniversityJinan 250021Shandong ProvinceChina Department of Radiology Shandong Province Qianfoshan HospitalJinan 250021Shandong ProvinceChina ge Healthcare MR Research ChinaBeijing 100000China Gong Ruozhen Innovation Studio Shandong Provincial ENT HospitalCheeloo College of MedicineShandong UniversityJinan 250021Shandong ProvinceChina Department of Radiology Shandong Province HospitalCheeloo College of MedicineShandong UniversityJinan 250021Shandong ProvinceChina

BACKGROUND Mature teratoma composed of all three basic germ cell layers of the head and neck is a rare *** involving the temporal bone are particularly *** SUMMARY A 48-year-old male patient with a history of chronic otitis of the left ear from infancy,for which he had been operated on twice,was referred to our hospital for chronic otitis,cholesteatoma and a middle ear *** tomography(CT)scan and magnetic resonance imaging(MRI)revealed a eustachian tube teratoma,in which the anterior lower part and posterior upper part were connected by a thin membranaceous *** mass was removed completely under general anesthesia by *** of last follow-up(2 years post-surgery),the disease had not *** Pre-operative CT and MRI are necessary for eustachian tube *** surgical resection provided excellent prognosis.

关键词： Eustachian tube Teratoma Chronic otitis Computed tomography Magnetic resonance imaging Case report

丙酮盐酸混合液提取土壤腐殖质组分的光谱学特征

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光谱学与光谱分析 2024年第2期44卷 474-479页

作者：宋鸽孔祥仕黑龙江大学中俄学院黑龙江哈尔滨150080 Institute of Earth Sciences St.Petersburg State UniversitySt.Petersburg 199034Russia 吉首大学旅游学院湖南吉首416000

采用丙酮盐酸混合液提取土壤胡敏酸(HA)和胡敏素(HU)组分,利用元素分析、紫外-可见漫反射光谱和红外光谱进行结构表征。元素分析表明,HA中C、H、N和S含量均高于HU,O含量低于HU。原子比分析表明HA的缩合度相对较高,分子结构相对复杂,HU... 详细信息

采用丙酮盐酸混合液提取土壤胡敏酸(HA)和胡敏素(HU)组分,利用元素分析、紫外-可见漫反射光谱和红外光谱进行结构表征。元素分析表明,HA中C、H、N和S含量均高于HU,O含量低于HU。原子比分析表明HA的缩合度相对较高,分子结构相对复杂,HU的缩合度相对较低,分子结构相对简单。紫外-可见漫反射光谱分析表明,由于腐殖质(HS)的组成复杂,多种官能团互相干扰,HA和HU紫外-可见漫反射光谱无明显特征峰,吸光度值随着波长的增加呈下降趋势,且HA包含的吸光有机成分较多,化学组成较复杂。HA和HU紫外特征参数SUV254和E4/E6比较分析表明,与HU相比,HA芳香性较大,腐殖化程度较高。红外光谱分析表明,HA和HU具有相似的红外光谱,各研究对象特征吸收峰的吸收强度不同,其中开垦黑土20~40 cm和未开垦灰土18~37 cm土层HA的振动幅度较大,说明其包含的酚类化合物、含羟基化合物、脂肪族化合物和羧酸,以及含羰基的醛、酮、醚等化合物的含量较多。开垦黑土10~20 cm土层和未开垦灰土18~37 cm土层HU在各特征吸收峰振动幅度较大,说明其包含的酚类化合物、羧酸、脂肪烃和糖类化合物含量较多。红外光谱各吸收峰强度比较分析表明,开垦后黑土HA和HU酚类化合物、羟基官能团和脂肪族化合物等含量增加,而开垦后灰土HA和HU酚类化合物、羧酸和脂肪族化合物含量下降,表明开垦对黑土土壤有机质影响相对较小,并且在一定程度上增加了土壤有机质含量,而促进了灰土土壤有机质的分解。综上所述,丙酮盐酸混合液提取法为HS生物化学和生理活性的研究提供了新的技术手段,为合理利用土壤资源提供理论依据。

关键词：胡敏酸胡敏素元素分析紫外-可见漫反射光谱近红外光谱

Erythrokeratodermia variabilis with hypertrichosis on the lesions

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Chinese Medical Journal 2020年第4期133卷 501-502页

作者： Jian-Ping Wu Hong-song ge Chao Yang Department of Dermatology Anhui Provincial Children's HospitalChildren's Hospital of Anhui Medical UniversityHefeiAnhui 230051China Department of Dermatology Dermatology HospitalSouthern Medical UniversityGuangzhouGuangdong 510091China

To the Editor:Erythrokeratodermia variabilis(EKV,Online Mendelian Inheritance in Man[OMIM]#133200)is a rare genodermatosis characterized by migratory erythema and fixed *** lesions have a predilection for the distal extremities,buttocks,and trunk.[1]However,abnormal hair growth on EKV lesions has rarely been reported.A 26-year-old Chinese man presented with widespread reddish-brown patches on his skin that had been present since the age of 5 *** lesions regressed spontaneously and then appeared elsewhere,gradually progressing to hyperkeratotic plaques with increasing numbers of hairs.

关键词： kerato lesions sis

黑龙江省耕地资源安全预警分析及预警系统的构建

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农业工程学报 2012年第6期28卷 247-252页

作者：宋戈连臣东北农业大学资源与环境学院哈尔滨150030

耕地资源安全预警是保护耕地和实现耕地资源可持续利用的有效手段。该文以黑龙江省为研究区,从耕地保护角度,结合研究区的耕地数量、质量和生态环境3个方面,构建耕地资源安全预警指标体系,利用纵比判断法,以研究区1996-2008年耕地资源... 详细信息

耕地资源安全预警是保护耕地和实现耕地资源可持续利用的有效手段。该文以黑龙江省为研究区,从耕地保护角度,结合研究区的耕地数量、质量和生态环境3个方面,构建耕地资源安全预警指标体系,利用纵比判断法,以研究区1996-2008年耕地资源安全定量评价值为基础数据,确定研究区耕地资源安全度的阈值。应用灰色模型GM(1.1)与BP人工神经网络技术,对黑龙江省2012-2015年耕地资源安全度及变化趋势进行了预测和分析,并构建了耕地资源预警系统框架体系。结果表明,1996-2008年黑龙江省耕地资源安全值呈不规则下降趋势。2012年黑龙江省耕地资源警度为轻警、2013-2015年为中警,警度有上升趋势;2012年耕地质量略有升高,但耕地数量减少幅度较大,2013-2015年,随着耕地数量的增加,耕地质量不断下降,2012-2015年生态环境呈平缓上升趋势。耕地数量与耕地质量不协调发展是黑龙江省耕地资源在预测期主要致警原因,城市化水平、水土流失比率和抗逆指数等是影响黑龙江省耕地资源安全状况的敏感因子。该文为相关预警研究提供参考。

关键词：土地利用,数量控制,预警,耕地资源安全,预警系统,黑龙江省