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Poor rich demarcation of Matthew effect on scale-free systems and its application
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作者 闫栋 董明 +1 位作者 Abdelaziz Bourasc 于随然 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期27-32,共6页
In a scale-free network, only a minority of nodes are connected very often, while the majority of nodes are connected rarely. However, what is the ratio of minority nodes to majority nodes resulting from the Matthew e... In a scale-free network, only a minority of nodes are connected very often, while the majority of nodes are connected rarely. However, what is the ratio of minority nodes to majority nodes resulting from the Matthew effect? In this paper, based on a simple preferential random model, the poor-rich demarcation points are found to vary in a limited range, and form a poor-rich demarcation interval that approximates to k/m E [3,4]. As a result, the (cumulative) degree distribution of a scale-free network can be divided into three intervals: the poor interval, the demarcation interval and the rich interval. The inequality of the degree distribution in each interval is measured. Finally, the Matthew effect is applied to the ABC analysis of project management. 展开更多
关键词 Matthew effect scale-free networks poor-rich demarcation project management
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In, Sn, Pb and Zn Contents and Their Relationships in Ore-forming Fluids from Some In-rich and In-poor Deposits in China 被引量:15
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作者 ZHANG Qian ZHU Xiaoqing +1 位作者 HE Yuliang ZHU Zhaohui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第3期450-462,共13页
All the indium-rich deposits with indium contents in ores more than 100×10^-6 seems to be of cassiterite-sulfide deposits or Sn-bearing Pb-Zn deposits, e.g., in the Dachang Sn deposit in Guangxi, the Dulong Sn-Zn... All the indium-rich deposits with indium contents in ores more than 100×10^-6 seems to be of cassiterite-sulfide deposits or Sn-bearing Pb-Zn deposits, e.g., in the Dachang Sn deposit in Guangxi, the Dulong Sn-Zn deposit in Yunnan, and the Meng'entaolegai Ag-Pb-Zn deposit in Inner Mongolia, the indium contents in ores range from 98×10^-6 to 236×10^-6 and show a good positive correlation with contents of zinc and tin, and their correlation coefficients are 0.8781 and 0.7430, respectively. The indium contents from such Sn-poor deposits as the Fozichong Pb-Zn deposit in Guangxi and the Huanren Pb-Zn deposit in Liaoning are generally lower than 10×10^-6, i.e., whether tin is present or not in a deposit implies the enrichment extent of indium in ores. Whether the In enrichment itself in the ore -forming fluids or the ore-forming conditions has actually caused the enrichment/depletion of indium in the deposits? After studying the fluid inclusions in quartz crystallized at the main stage of mineralization of several In-rich and In-poor deposits in China, this paper analyzed the contents and studied the variation trend of In, Sn, Pb and Zn in the ore-forming fluids. The results show that the contents of lead and zinc in the ore-forming fluids of In-rich and -poor deposits are at the same level, and the lead contents range from 22×10^-6 to 81×10^-6 and zinc from 164×10^-6 to 309×10^-6, while the contents of indium and tin in the ore-forming fluids of In-rich deposits are far higher than those of Inpoor deposits, with a difference of 1-2 orders of magnitude. Indium and tin contents in ore-forming fluid of In-rich deposits are 1.9×10^-6-4.1×10^-6 and 7×10^-6-55×10^-6, and there is a very good positive correlation between the two elements, with a correlation coefficient of 0.9552. Indium and tin contents in ore-forming fluid of In-poor deposits are 0.03×10^-6-0.09×10^-6 and 0.4×10^-6-2.0×10^-6, respectively, and there is no apparent correlation between them. This indicates, on one hand, that In-rich oreforming fluids are the material basis for the formation of In-rich deposits, and, on the other hand, tin probably played a very important role in the transport and enrichment of indium. 展开更多
关键词 In-rich deposit In-poor deposit ore-forming fluid fluid inclusion ore-forming elements
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On the Pain Points and Governance of the Constructionof the Socialist Market Economy in Contemporary China
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作者 夏德建 《石家庄经济学院学报》 2016年第3期6-10,共5页
经过3 0 多年的改革开放,中国的社会主义市场经济建设取得了丰硕成果,成为了中国特色社会主义制度的重要支柱,奠定了建设全面小康社会的坚实基础.但是,随着我国经济步入深化发展与转型调整阶段,市场的优化配置功能在社会管理、公共产品... 经过3 0 多年的改革开放,中国的社会主义市场经济建设取得了丰硕成果,成为了中国特色社会主义制度的重要支柱,奠定了建设全面小康社会的坚实基础.但是,随着我国经济步入深化发展与转型调整阶段,市场的优化配置功能在社会管理、公共产品供应等民生问题上出现了越位、缺位等异化现象,引发了官民对立、干群关系紧张、贫富两极分化、社会保障缺失等不和谐问题,严重掣肘了中国社会主义市场经济的健康与持续发展D 为治理上述痛点,论文提出了党要坚持执政为民的治国理念、完善社会考评制度、合理分配社会财富、健全社会保障体系等治理上的一些简单思路,以起抛砖引玉之效. 展开更多
关键词 社会主义市场经济 改革开放 资源分配 贫富差距 社会保障
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The Rich Help the Poor
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《China Today》 1997年第2期12-14,共3页
关键词 the rich Help the poor
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The Rich Help the Poor
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作者 KUANG YI 《China Today》 1996年第10期41-43,共3页
TheRichHelpthePoorMoreandmorewealthyregionsandbusinesspeopleareparticipatinginthecampaignagainstpoverty,andh... TheRichHelpthePoorMoreandmorewealthyregionsandbusinesspeopleareparticipatinginthecampaignagainstpoverty,andhavemadeconsiderab... 展开更多
关键词 the rich Help the poor
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Species richness and biodiversity significance of alpine micro-waterbody systems in Gaoligong Mountain, Northwest Yunnan, China 被引量:1
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作者 LIU Shuo-Ran Davide FORNACCA +8 位作者 YANG Dao-De TAN Lu LI Xian-Fu REN Guo-Peng SUN Jun HE Xiao-Yang YANG Wen-Shu CAI Qing-Hua XIAO Wen 《Journal of Mountain Science》 SCIE CSCD 2020年第4期907-918,共12页
Water quality, size, connectivity and other physical properties of hydrological systems might have different functions in the formation and maintenance of biodiversity, but this remains mostly unclear due to the lack ... Water quality, size, connectivity and other physical properties of hydrological systems might have different functions in the formation and maintenance of biodiversity, but this remains mostly unclear due to the lack of undisturbed sites for experimental modelling. Alpine freshwater habitats such as micro-waterbodies(MWB) represent a kind of natural system suitable for biodiversity research. In order to assess potential linkages between environmental factors, connectivity of MWBs and aquatic species richness, we conducted a pilot study in two separated MWB systems located in Gaoligong Mountain, northwest Yunnan province, China. A total of 27 MWBs have been analyzed, including 22 connected and 5 isolated bodies. 13 conventional environmental factors were tested while all kinds of aquatic macro-organisms were collected and classified. Results showed a high environmental heterogeneity among MWBs and significant differences between the two systems but only a few environmental variables such as the depth of soil bottom, total Nitrogen and altitude were related to species richness and the formation of the community structure. As a benefit from the high environmental heterogeneity, the cascaded MWB systems provided divergent habitats able to support species richness at a higher level than the same number of randomly selected MWBs. This finding supports the idea that habitat connectivity matters also in extremely small aquatic ecosystems. Moreover, although still a preliminary result, a polarization effect within connected chains where edge MWBs host higher taxa and endemic taxa richness as well as larger populations, was detectable. This study gives interesting insights on the spatial processes driving community structure and a new prospective for biodiversity conservation. Since alpine MWBs have significant effects on the maintenance of watershed biodiversity, further research on such small and crucial ecosystems is encouraged. 展开更多
关键词 HABITAT CONNECTIVITY High MOUNTAIN Extreme fine scale Cascaded WATER system richness maintenance Polarized dispersal
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Neutron-Capture Elements in the Double-Enhanced Star HE 1305-0007: a New s- and r-Process Paradigm
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作者 崔文元 崔冬暖 +1 位作者 杜云霜 张波 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第5期1417-1420,共4页
The star HE 1305-0007 is a metal-poor double-enhanced star with metallicity [Fe/H] = -2.0, which is just at the upper limit of the metallicity for the observed double-enhanced stars. Using a parametric model, we find ... The star HE 1305-0007 is a metal-poor double-enhanced star with metallicity [Fe/H] = -2.0, which is just at the upper limit of the metallicity for the observed double-enhanced stars. Using a parametric model, we find that almost all s-elements were made in a single neutron exposure. This star should be a member of a post-commonenvelope binary. After the s-process material has experienced only one neutron exposure in the nucleosynthesis region and is dredged-up to its envelope, the AGB evolution is terminated by the onset of common-envelope evolution. Based on the high radial-velocity of HE 1305-0007, we speculate that the star could be a runaway star from a binary system, in which the AIC event has occurred and produced the r-process elements. 展开更多
关键词 ASYMPTOTIC GIANT BRANCH METAL-poor STARS rich STARS GALACTIC HALO CARBONSTARS DREDGE-UP EVOLUTION NUCLEOSYNtheSIS MODEL ORIGIN
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Narrowing Gap Between Rich and Poor
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作者 STAFF REPORTER YUN XIANG 《The Journal of Human Rights》 2005年第2期14-16,共3页
Inequality in distribution has become an issue of public concern in China. Incomes of the Chinese people have grown year after year ever since the reform and opening era began in the late 1970s. Meanwhile, the income ... Inequality in distribution has become an issue of public concern in China. Incomes of the Chinese people have grown year after year ever since the reform and opening era began in the late 1970s. Meanwhile, the income gap between urban and rural residents has widened constantly, from 1.8:1 in the mid-1980s to 3.2:1 in 2003. In a report entitled Analysis and Forecast of China's Social Conditions 2004-2005, experts with the Chinese Academy of Social Sciences listed the widening income gaps as the second most serious of the six problems China is facing. The report notes that such gaps have kept widening not only between individual workers in the same profession but also between workers in different industries and regions. In view of this, the national economic work conference held in early January called for effort to improve the order of income distribution and readjust the distribution of national wealth in an appropriate manner. How to view the problem of inequality in distribution as we see now? How the divide of the rich and the poor affects the improvement of human rights? What should be done to narrow the gap between the rich and the poor? We have dis- cussed these questions with two leading social scientists in China, Sun Guohua, pro- fessor of law at the Renmin University of China and Prof. Hu Angang of Qinghua University, a noted expert in study of the conditions in China. 展开更多
关键词 Narrowing Gap Between rich and poor rich BANK HIGH World
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Rejuvenation of Ovary and Thin Endometrium by Autologous PRP Injection in POR and Recurrent Implantation Failure 被引量:1
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作者 Yazhini Selvaraj Kanchana Malaisamy 《Advances in Sexual Medicine》 2021年第1期1-15,共15页
In India</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> the problem of infertility is growing and in the last 5 years</span><s... In India</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> the problem of infertility is growing and in the last 5 years</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> it has gone up to 20%</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">30%. This ongoing prospective clinical study brings forth a novel, innovative, effective, simple, affordable, easily performed outpatient procedure (OP) and a promising therapeutic method in rejuvenating the Ageing Ovaries and Thin Endometrium, with autologous Platelet Rich Plasma (PRP). This clinical study proves to give a better result in rejuvenating Ovary and treating the Thin Endometrium. This pilot study include</span><span style="font-family:Verdana;">d</span><span style="font-family:Verdana;"> five women (28</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">44 years) with Poor Ovarian Response (POR), Premature Ovarian Insufficiency (POI) and Perimenopause and Thirty-nine women (22</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">43</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">years.) with recurrent implantation failure due to Thin Endometrium were subjected to autologous PRP instillation under Ultrasound Guidance, and Hysteroscopic guided PRP. After PRP</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> a significant output was obtained, with improved Anti Mullerian Hormone (AMH) and Antral Follicle Count (AFC) and out of five women three women conceived by Intra Cytoplasmic Sperm Injection (ICSI). PRP injected in women with Poor Ovarian Response found successful ovarian rejuvenation within 1</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-size:10pt;font-family:""> </span><span style="font-family:Verdana;">3 months and had a 60% of pregnancy rate, PRP into the endometrium had 53.8% successful pregnancies. We have not encountered any complications. 展开更多
关键词 Platelet rich Plasma (PRP) poor Ovarian Reserve (POR) Premature Ovarian Insufficiency (POI) Anti Mullerian Hormone (AMH) Antral Follicle Counts (AFC) Intra Cytoplasmic Sperm Injection (ICSI) Outpatient Procedure (OP)
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Genetic causes of oil-rich and oil-poor reservoirs: Implications from two Cenozoic basins in the eastern North China Craton 被引量:2
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作者 Chiyang LIU Lei HUANG +4 位作者 Dongdong ZHANG Junfeng ZHAO Yu DENG Pei GUO Yijian HUANG &Jianqiang WANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第12期1910-1931,共22页
The Bohai Bay and Hehuai(southern North China) rift basins in the eastern part of the North China Craton are southnorth-adjacent. They have shown synchronous evolutionary processes, and possess generally identical sup... The Bohai Bay and Hehuai(southern North China) rift basins in the eastern part of the North China Craton are southnorth-adjacent. They have shown synchronous evolutionary processes, and possess generally identical superficial and shallow structural characteristics as well as similar basin areas. However, there is a large difference in the richness of oil resources between the two basins. The Bohai Bay Basin has extremely abundant oil reserves, while commercial oil reserves have not been found in the Hehuai Basin. The deep tectonic structures, magmatic activities, and modern and paleo-geothermal fields of the two basins are significantly different. Compared with the Hehuai Basin, the Bohai Bay Basin has a thinner crust and more complex structure with multiple low-velocity layers. It is also characterized by intense magmatic activity, high modern and paleogeothermal fields, frequent seismic activity, and active deep interactions, small effective elastic thickness of the isotropic lithosphere, and shorter balanced transformation wavelength of the lithosphere with a high likelihood of local compensation. The Hehuai Basin has a simple deep structure and homogeneous crustal composition, with a high likelihood of regional compensation. The characteristics of the deep structures mentioned above are generally similar to those of the southern part of the stable Ordos Basin, except for the smaller crust thickness. This indicates the presence of differences in Mesozoic destruction between the southern and northern zones in the eastern part of the North China Craton. The northern zone was subjected to significant destruction, while the southern zone was subjected to modifications, primarily in the form of local changes in the structures and/or properties of the crust or lithospheric mantle, with the overall structure and stability of the craton kept intact. The formation of high-quality source rock is primarily influenced by the abnormal flourishment of organisms in water bodies during the syndepositional period, and is also strongly associated with the high geothermal setting of basins and nutrients from hydrothermal solutions and volcanoes. In other words, it is mainly controlled by deep processes and deep-major fault activity. The differences in the deep structures and modern and paleo geothermal fields of the two basins correspond to the difference in richness of oil resources, suggesting that there is an important internal or causal relationship between the two aspects. This viewpoint coincides with the conditions and environments required for the development of high-quality source rock in hydrocarbon-rich basins(sags)in China and other countries, and is evidenced by the modern lake basin of the East African Rift. A new hydrocarbon generation model is proposed in this work: petroleum is a comprehensive product of the integration of bioenergy, thermal energy, and other related energies(such as chemical and kinetic energy) and their interactions; the degree of richness of petroleum is generally controlled by the regional tectonic structure, thermal environment, and deep processes; nonmarine basins or depressions with abundant resources are closely related to active deep processes, intense exchange of material between the deep and shallow layers, participation of external hydrocarbons, and energy integration and conversion. 展开更多
关键词 GENETIC CAUSES of oil-rich and oil-poor RESERVOIRS Bohai Bay Basin Hehuai Basin Destruction of North China Craton Deep processes High-quality source rock formation
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基尼系数测度贫富差距的一种改进方法
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作者 彭妮娅 《统计与决策》 北大核心 2024年第4期12-16,共5页
基尼系数是测度贫富差距的重要指标,但是洛伦兹曲线的构造使得基尼系数存在结构性局限,即代表着不同的贫富差距情况的两条洛伦兹曲线可能对应着同一个基尼系数,仅凭基尼系数无法反映贫富差距的结构特征。文章提出将洛伦兹曲线上切线斜率... 基尼系数是测度贫富差距的重要指标,但是洛伦兹曲线的构造使得基尼系数存在结构性局限,即代表着不同的贫富差距情况的两条洛伦兹曲线可能对应着同一个基尼系数,仅凭基尼系数无法反映贫富差距的结构特征。文章提出将洛伦兹曲线上切线斜率为1的点叫做平均增长点,每条洛伦兹曲线有且仅有一个平均增长点,洛伦兹曲线切线斜率具有单调性,可以通过引入平均增长点,与基尼系数共同测度贫富差距,突破单纯依靠基尼系数测度贫富差距的结构性局限。 展开更多
关键词 基尼系数 贫富差距 结构性局限 平均增长点
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冷冻保存富血小板血浆对创伤修复的影响及体外机制研究
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作者 苏睿 董良 +1 位作者 潘钊 闻慧琴 《安徽医科大学学报》 CAS 北大核心 2024年第7期1143-1150,共8页
目的评估-80℃超低温冷冻保存后冻融的富血小板血浆(PRP)对伤口愈合相关细胞的影响,揭示超低温冻融的PRP在创伤修复中的机制,明确低温冷冻保存PRP对促进伤口愈合应用的可行性和有效性。方法使用未激活的新鲜PRP、钙离子激活的新鲜PRP和... 目的评估-80℃超低温冷冻保存后冻融的富血小板血浆(PRP)对伤口愈合相关细胞的影响,揭示超低温冻融的PRP在创伤修复中的机制,明确低温冷冻保存PRP对促进伤口愈合应用的可行性和有效性。方法使用未激活的新鲜PRP、钙离子激活的新鲜PRP和冻融后PRP分别与巨噬细胞、成纤维细胞和血管形成细胞共培养,测定比较巨噬细胞极化与炎症反应相关因子的表达及细胞迁移率和增殖率等多项指标,分析PRP对巨噬细胞极化、炎症及细胞增殖的影响。结果与对照组比较,超低温冻融后的PRP使巨噬细胞M1样极化基因iNOS表达降低(P<0.0001),NO分泌减少(P<0.001),尿素含量增加(P<0.0001),M1相关炎性因子肿瘤坏死因子-α(TNF-α)降低(P<0.001),白细胞介素(IL)-1分泌降低(P<0.001),M2相关抗炎因子IL-10、IL-12分泌水平增加(P<0.01,P<0.05)。此外,冻融PRP共培养明显促进细胞迁移,提高了血管形成效率,高于新鲜PRP组(P<0.01),与激活PRP组效果相当。细胞活死染色和CCK-8增殖实验也显示与冻融PRP共培养的L929和HUVEC细胞增殖率均显著增加(P<0.01)。结论-80℃超低温冷冻保存后的PRP能够显著增强细胞的迁移、分化和增殖能力,同时抑制炎症因子产生,促进巨噬细胞的M2样极化。低温冷冻保存可被视为一种有效的PRP保存方法。 展开更多
关键词 富血小板血浆 低温冷冻保存 巨噬细胞极化 创伤修复 血管形成
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SH3BGRL对胃癌细胞增殖、迁移的影响
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作者 颜海清 赖沁巧 +4 位作者 吴留成 王婷安 夏想 黄名威 覃宇周 《中国癌症防治杂志》 CAS 2024年第3期285-294,共10页
目的探讨SH3结构域结合富含谷氨酸的蛋白质(SH3 binding glutamic acid-rich protein like,SH3BGRL)对胃癌细胞增殖、迁移能力的影响及其作用机制。方法基于TCGA、GTEx及GEO数据库,通过生物信息学分析SH3BGRL在胃癌组织及正常胃黏膜上... 目的探讨SH3结构域结合富含谷氨酸的蛋白质(SH3 binding glutamic acid-rich protein like,SH3BGRL)对胃癌细胞增殖、迁移能力的影响及其作用机制。方法基于TCGA、GTEx及GEO数据库,通过生物信息学分析SH3BGRL在胃癌组织及正常胃黏膜上皮组织中的表达情况;通过HPA数据库获取SH3BGRL蛋白在胃癌组织及正常胃黏膜上皮组织中的表达图谱;并基于TCGA数据库的SH3BGRL表达水平进行高、低表达分组,分析其对胃癌患者预后、免疫细胞浸润和免疫治疗的影响。通过临床标本IHC染色观察SH3BGRL蛋白在胃癌中的表达情况;采用RT-qPCR检测SH3BGRL在胃癌细胞系和正常胃黏膜上皮细胞GES-1中的表达水平。将胃癌HGC-27及NCI-N87细胞进行siRNA转染分为si-NC组(转染阴性对照组)、si-SH3BGRL组(沉默SH3BGRL组),并通过RT-qPCR及Western blot验证是否转染成功。采用CCK-8及Transwell实验检测细胞增殖和迁移能力,随后诱导THP-1单核细胞分化为M0巨噬细胞,并将分化后的M0巨噬细胞和转染后的胃癌细胞进行共培养,采用RT-qPCR及细胞免疫荧光检测共培养之后M2巨噬细胞标志物的改变,并采用RT-qPCR检测SH3BGRL沉默胃癌细胞中CSF1的表达水平。结果生物信息学分析结果显示,与正常胃黏膜上皮组织相比,SH3BGRL在胃癌组织中表达上调(均P<0.01),且SH3BGRL高表达者总生存期和无进展生存期比SH3BGRL低表达的患者短(均P<0.01)。SH3BGRL高表达者M2巨噬细胞浸润比例更高,与免疫治疗低应答率相关(均P<0.01)。IHC染色结果表明,SH3BGRL蛋白在胃癌组织中表达上调(P<0.001)。与GES-1细胞相比,SH3BGRL在胃癌HGC-27及NCI-N87细胞中的mRNA表达水平均显著上调(均P<0.01)。与si-NC组相比,沉默SH3BGRL后HGC-27和NCI-N87细胞的增殖能力明显下降(均P<0.01),HGC-27细胞迁移能力显著下降(P<0.01)。M0巨噬细胞与沉默SH3BGRL的HGC-27及NCI-N87共培养后,M2巨噬细胞标志物CD163、CD206及Arg1均下调(均P<0.01)。在HGC-27及NCIN87细胞中沉默SH3BGRL后,NF-κB信号通路的靶基因CSF1显著下调(均P<0.01)。结论SH3BGRL在胃癌中表达上调,沉默SH3BGRL能抑制胃癌细胞增殖和迁移,其机制可能与抑制M2巨噬细胞极化进而形成免疫抑制肿瘤微环境有关。 展开更多
关键词 胃癌 SH3结构域结合富含谷氨酸的蛋白质 增殖 迁移 肿瘤微环境 M2巨噬细胞极化
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主佃借贷与贫富相资——对宋代契约租佃制下富民借贷的探讨
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作者 黎志刚 《思想战线》 北大核心 2024年第1期75-82,共8页
宋代是我国古代民间借贷关系空前发展的重要时期。随着富民阶层的崛起和契约租佃主导地位的确立,民间借贷关系与契约租佃关系的结合表现得越来越紧密,有效地实现了生产要素的优化配置,逐渐成为当时重要的制度选择和制度安排。而宋政府... 宋代是我国古代民间借贷关系空前发展的重要时期。随着富民阶层的崛起和契约租佃主导地位的确立,民间借贷关系与契约租佃关系的结合表现得越来越紧密,有效地实现了生产要素的优化配置,逐渐成为当时重要的制度选择和制度安排。而宋政府也逐渐认识并重视这一点,利用主佃借贷来实现贫富相资,促进了乡村经济的稳定和发展。 展开更多
关键词 契约租佃关系 富民阶层 主佃借贷 贫富相资
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Co_(3)O_(4)@碳纤维诱导贫/富电子中心活化PMS高效降解2,4-二氯酚
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作者 张禹洵 卫月星 +4 位作者 焦路畅 秦育红 申浩楠 贺冲 崔丽萍 《太原理工大学学报》 CAS 北大核心 2024年第3期538-549,共12页
【目的】工业快速发展导致水体中氯酚类污染物含量上升,对生态系统和人类生存发展造成影响,高效降解工业废水中难降解污染物2,4-二氯酚(2,4-DCP)成为。【方法】通过一步浸渍法制备了具有贫/富电子活性中心的Co_(3)O_(4)包覆碳纤维催化剂... 【目的】工业快速发展导致水体中氯酚类污染物含量上升,对生态系统和人类生存发展造成影响,高效降解工业废水中难降解污染物2,4-二氯酚(2,4-DCP)成为。【方法】通过一步浸渍法制备了具有贫/富电子活性中心的Co_(3)O_(4)包覆碳纤维催化剂(Co_(3)O_(4)@CF),并应用于活化过硫酸盐降解2,4-DCP研究中。【结果】研究结果表明,Co_(3)O_(4)被均匀的涂覆在具有规则骨架结构的碳纤维表面,在Co(Ⅱ)-π的相互作用下形成了富电子钴中心和贫电子碳中心。在pH值为3.0~7.8,2,4-DCP的质量浓度为50mg/L,Co_(3)O_(4)@CF质量浓度为0.1g/L,PMS浓度为10mmol/L的初始条件下,Co_(3)O_(4)@CF在20min内可实现2,4-DCP的完全降解。在此过程中,Co_(3)O_(4)@CF可诱导反应体系中电子从贫电子中心向富电子中心转移,实现Co_(3+)的快速还原和PMS的快速活化。表征结果也进一步证明,碳纤维不仅可以作为载体,还可以通过其结构缺陷参与过硫酸盐活化的链式自由基反应,从而促进SO_(4)^(-)·转换为1O_(2)和O_(2)^(-)·,达到高效降解2,4-DCP的目的。 展开更多
关键词 碳纤维 Co_(3)O_(4) 贫/富电子中心 2 4-二氯酚 催化降解
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激电测深方法在东北地区松散岩类地下水探查中的应用
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作者 何清立 蒙凯 《工程地球物理学报》 2024年第4期636-644,共9页
本文对东北平原地区某城市下辖206个村屯集中式城乡供水工程进行前期地下水探查工作,主要目的是了解和掌握区域范围内地下含水层分布情况,寻找地下水赋存层位大致深度和分布规律,并对富水性进行分析和验证,为后期钻探和布井工作提供技... 本文对东北平原地区某城市下辖206个村屯集中式城乡供水工程进行前期地下水探查工作,主要目的是了解和掌握区域范围内地下含水层分布情况,寻找地下水赋存层位大致深度和分布规律,并对富水性进行分析和验证,为后期钻探和布井工作提供技术指导。本次研究主要利用激电测深方法技术,通过数据采集及成果解译,最终将工作区地层划分出3类含水层,由上至下依次为冲积砂潜水含水层、中细砂潜水含水层以及砂砾岩承压含水层,其中潜水含水层在地表以下30 m深度范围内,承压含水层在地下深部70 m以下,同时展示了不同含水层在探查范围内顶板埋深的分布情况。通过对地层富水性分析,全区85%平面范围内富水性表现强富水-中等富水,15%平面范围富水性表现弱富水性。最终通过钻孔对解译推断结论进行验证,结果基本吻合,证明了激电测深法在该地区地层找水方面的适用性。 展开更多
关键词 地下水 富水性 激电测深法 钻孔
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元宇宙视域下贫富差距的问题分析和治理之策
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作者 沈先陈 《合肥大学学报》 2024年第3期79-86,共8页
元宇宙以前所未有的方式深层次地影响了人类社会,并可能导致人类社会的贫富差距进一步扩大。究其原因,元宇宙由于其经济技术和人员的门槛过高,容易导致资本垄断资源,并进一步加剧资本对劳动者的剥削,进而导致人类社会贫富差距拉大。有... 元宇宙以前所未有的方式深层次地影响了人类社会,并可能导致人类社会的贫富差距进一步扩大。究其原因,元宇宙由于其经济技术和人员的门槛过高,容易导致资本垄断资源,并进一步加剧资本对劳动者的剥削,进而导致人类社会贫富差距拉大。有鉴于此,出于对元宇宙发展带来的人类社会贫富差距的警思,应考虑以普惠发展来降低其门槛,以制度建构来规制资源合理分配,以技术和法律规制来削弱资本对劳动者的剥削,从而有效解决元宇宙发展带来的贫富差距问题,造福人类社会。 展开更多
关键词 元宇宙 贫富差距 虚拟世界 资源垄断 技术
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Regulation of ApoE Gene Expression in Mouse Peritoneal Macrophages by VLDL
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作者 冯友梅 从容 +3 位作者 宗义强 张建民 屈伸 邓耀祖 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1997年第2期65-67,97,共4页
Mouse peritoneal macrophages (MPM) were incubated with ApoEpoor VLDL or ApoE-rich VLDL at same concentrations for 24 h. The ApoE mR NA content increased in both groups than that in control and the highest ApoEmRNA con... Mouse peritoneal macrophages (MPM) were incubated with ApoEpoor VLDL or ApoE-rich VLDL at same concentrations for 24 h. The ApoE mR NA content increased in both groups than that in control and the highest ApoEmRNA content was seen in MPM incubated with ApoE-poor VLDL. The results suggest that VLDL could stimuIate ApoE gene expression in MPM and the ApoE poor VLDL has more pronounced effect. We think that the ApoE secreted byMPM may be incorporated into VLDL, especially the ApoE-poor VLDL, and thereby enhance the uptake of those lipoproteins by MPM or other local cells via ApoE-mediated receptor pathways. 展开更多
关键词 ApoE-poor VLDL ApoE-rich VLDL macrophages ApoE gene expression
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The Profound Changes Unseen in a Century: The Perspective of Overlapping Effect of Technological Revolution Cycle and Political & Economic Thought Cycle
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作者 Zhijian Hu Mingxi Zhang Xinyue Zhu 《Innovation and Development Policy》 2019年第2期119-131,共13页
The waves of technological revolution can lead to great differences in the economic and social structures of countries and have a destructive impact. The choice of political and economic thoughts can amplify or inhibi... The waves of technological revolution can lead to great differences in the economic and social structures of countries and have a destructive impact. The choice of political and economic thoughts can amplify or inhibit such differentiation and impact. Over the past 100 years, humankind has undergone three technological revolutions, and the mainstream political and economic thoughts have experienced a cycle from classical liberalism to various types of anti-liberalism and finally to neoliberalism. In the two liberal periods, the overlap of liberalism and a technological revolution caused sharp contradictions between the rich and the poor, leading to profound economic adjustment and great political and social turmoil worldwide. In the non-liberal period, however, the overlapping effects were relatively mild. Currently, the world is facing similar trends and risks as during 1914-1940. Whether humankind will repeat the same mistakes merits attention and vigilance. This study argues that it is necessary to oppose unilateralism, uphold multilateralism, and advance globalization and free trade under the concept of collaborative development and shared prosperity, as well as explore comprehensive and sustainable development. These are of great significance for human society to prevent risks, obtain advantages and avoid disadvantages, and maintain world peace and development. 展开更多
关键词 profound changes unseen in a century technological revolution political and economic thoughts polarization between the rich and the poor risk response
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富血小板血浆在生殖医学领域应用的研究进展
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作者 袁彩霞 杨欢 +1 位作者 宋海霞 范玲玲 《中国计划生育学杂志》 2023年第5期1242-1246,共5页
富血小板血浆(PRP)是一种高浓度血小板血浆,被应用于临床多个学科,本文旨在总结和评价PRP在生殖医学领域的作用,包括薄型子宫内膜、反复着床失败(RIF)、慢性子宫内膜炎和卵巢功能低下等方面,期望为PRP在生殖领域的临床治疗及未来的科学... 富血小板血浆(PRP)是一种高浓度血小板血浆,被应用于临床多个学科,本文旨在总结和评价PRP在生殖医学领域的作用,包括薄型子宫内膜、反复着床失败(RIF)、慢性子宫内膜炎和卵巢功能低下等方面,期望为PRP在生殖领域的临床治疗及未来的科学研究提供参考。 展开更多
关键词 富血小板血浆 薄型子宫内膜 复发性着床失败 慢性子宫内膜炎 卵巢功能低下
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