期刊文献+
共找到74篇文章
< 1 2 4 >
每页显示 20 50 100
头颈鳞状细胞癌组织与正常黏膜中血管生成因子1和2的表达 被引量:7
1
作者 郑美桦 Florian Veelken +2 位作者 Daniel Lábbe Wilhelm bloch Olaf Michel 《中华耳鼻咽喉头颈外科杂志》 CAS CSCD 北大核心 2005年第5期371-375,共5页
目的 研究血管生成因子1(angiopoietin -1,Ang -1)和2(Ang- 2)在头颈鳞状细胞癌(简称鳞癌)及健康黏膜组织中的表达及意义。方法 采用免疫组化法,观测了45例头颈部鳞癌组织和7例健康志愿者口腔黏膜组织中Ang -1和Ang- 2的表达及分布。... 目的 研究血管生成因子1(angiopoietin -1,Ang -1)和2(Ang- 2)在头颈鳞状细胞癌(简称鳞癌)及健康黏膜组织中的表达及意义。方法 采用免疫组化法,观测了45例头颈部鳞癌组织和7例健康志愿者口腔黏膜组织中Ang -1和Ang- 2的表达及分布。分析了不同临床分期及不同病理分级的癌组织中Ang- 1和Ang -2表达水平及其意义。结果 Ang -1和Ang- 2在血管内皮细胞、健康黏膜上皮细胞及鳞癌细胞内均有表达;Ang -1在肿瘤的血管内皮细胞及癌细胞的阳性表达率分别为78% (35 /45)和87% (39 /45),Ang 2在肿瘤的血管内皮细胞及癌细胞的阳性表达率分别为69% (31 /45)和76% (34 /45),均高于健康黏膜的血管内皮细胞及上皮细胞内的表达(P<0 .05);肿瘤血管内皮细胞与鳞癌细胞内Ang-1、Ang -2的表达水平有关(P<0 .05);Ang- 1在肿瘤血管内皮细胞中的表达水平与肿瘤的临床分期有关,在ⅢⅣ期比在ⅠⅡ期高(P<0 .05);Ang -2在肿瘤的血管内皮细胞及鳞癌细胞中的表达也表现为ⅢⅣ期比ⅠⅡ期高(P<0. 05);Ang -1及Ang- 2的表达水平在高、中、低分化的癌组织中的差异无统计学意义(P>0 .05)。结论 肿瘤血管内皮细胞与鳞癌细胞内Ang- 1、Ang -2的表达水平有关,且分别高于健康黏膜的血管内皮细胞及上皮细胞的表达。晚期肿瘤的血管生成与Ang - 展开更多
关键词 头颈鳞状细胞癌 肿瘤组织 黏膜 血管生成因子1 血管生成因子2 基因表达
原文传递
The Digital Agricultural Knowledge and Information System(DAKIS):Employing digitalisation to encourage diversified and multifunctional agricultural systems
2
作者 Ioanna Mouratiadou Nahleen Lemke +17 位作者 Cheng Chen Ariani Wartenberg Ralf bloch Marco Donat Thomas Gaiser Deepak Hanike Basavegowda Katharina Helming Seyed Ali Hosseini Yekani Marcos Krull Kai Lingemann Joseph Macpherson Marvin Melzer Claas Nendel Annette Piorr Mostafa Shaaban Peter Zander Cornelia Weltzien Sonoko Dorothea Bellingrath-Kimura 《Environmental Science and Ecotechnology》 SCIE 2023年第4期177-189,共13页
Multifunctional and diversified agriculture can address diverging pressures and demands by simultaneously enhancing productivity,biodiversity,and the provision of ecosystem services.The use of digital technologies can... Multifunctional and diversified agriculture can address diverging pressures and demands by simultaneously enhancing productivity,biodiversity,and the provision of ecosystem services.The use of digital technologies can support this by designing and managing resource-efficient and context-specific agricultural systems.We present the Digital Agricultural Knowledge and Information System(DAKIS)to demonstrate an approach that employs digital technologies to enable decision-making towards diversified and sustainable agriculture.To develop the DAKIS,we specified,together with stakeholders,requirements for a knowledge-based decision-support tool and reviewed the literature to identify limitations in the current generation of tools.The results of the review point towards recurring challenges regarding the consideration of ecosystem services and biodiversity,the capacity to foster communication and cooperation between farmers and other actors,and the ability to link multiple spatiotemporal scales and sustainability levels.To overcome these challenges,the DAKIS provides a digital platform to support farmers'decision-making on land use and management via an integrative spatiotemporally explicit approach that analyses a wide range of data from various sources.The approach integrates remote and in situ sensors,artificial intelligence,modelling,stakeholder-stated demand for biodiversity and ecosystem services,and participatory sustainability impact assessment to address the diverse drivers affecting agricultural land use and management design,including natural and agronomic factors,economic and policy considerations,and socio-cultural preferences and settings.Ultimately,the DAKIS embeds the consideration of ecosystem services,biodiversity,and sustainability into farmers'decision-making and enables learning and progress towards site-adapted small-scale multifunctional and diversified agriculture while simultaneously supporting farmers'objectives and societal demands. 展开更多
关键词 Digital agriculture Ecosystem services Decision support system Farming practices BIODIVERSITY MODELLING Small-scale management
原文传递
Direct observation of photonic Landau levels and helical edge states in strained honeycomb lattices 被引量:4
3
作者 Omar Jamadi Elena Rozas +9 位作者 Grazia Salerno Marijana Milicevic Tomoki Ozawa Isabelle Sagnes Aristide Lemaitre Luc Le Gratiet Abdelmounaim Harouri Iacopo Carusotto Jacqueline bloch Alberto Amo 《Light(Science & Applications)》 SCIE EI CAS CSCD 2020年第1期627-636,共10页
We report the realization of a synthetic magnetic field for photons and polaritons in a honeycomb lattice of coupled semiconductor micropillars.A strong synthetic field is induced in both the s and p orbital bands by ... We report the realization of a synthetic magnetic field for photons and polaritons in a honeycomb lattice of coupled semiconductor micropillars.A strong synthetic field is induced in both the s and p orbital bands by engineering a uniaxial hopping gradient in the lattice,giving rise to the formation of Landau levels at the Dirac points.We provide direct evidence of the sublattice symmetry breaking of the lowest-order Landau level wavefunction,a distinctive feature of synthetic magnetic fields.Our realization implements helical edge states in the gap between n=0 and n=±1 Landau levels,experimentally demonstrating a novel way of engineering propagating edge states in photonic lattices.In light of recent advances in the enhancement of polariton–polariton nonlinearities,the Landau levels reported here are promising for the study of the interplay between pseudomagnetism and interactions in a photonic system. 展开更多
关键词 LANDAU HELICAL REALIZATION
原文传递
Composition Changes and Movements in Mixed-Species Groups of Algae Grazing Fish in Jamaica and Grand Cayman Island. Part II
4
作者 Andrew bloch Layla Al-Shaer +2 位作者 Brandon Baumann Matthew Draud M. Itzkowitz 《Open Journal of Marine Science》 2021年第1期41-54,共14页
Although Caribbean mixed-species herbivorous fish groups are an important component to the reef community by helping to crop algae that often overgrow and kill corals, little is known of how they organize their foragi... Although Caribbean mixed-species herbivorous fish groups are an important component to the reef community by helping to crop algae that often overgrow and kill corals, little is known of how they organize their foraging groups. In spite of a highly flexible membership, the basic structure of these groups consists of a “core species,” that leads the group and often is either the striped parrotfish <i>(Scarus iserti)</i> or the ocean surgeon <i>(Acanthurus tractus)</i>. These species lead their groups to open areas where they feed largely on low profile turf algae. Other members prefer macro algae and are termed “associate species,” of which the two common species we studied were the stoplight parrotfish <i>(Sparisoma viride)</i> and the redband parrotfish <i>(Sparisoma aurofrenatum)</i>. In spite of the large difference in group sizes between Jamaica and Grand Cayman Islands, the relationships between movement patterns and compositional changes were largely consistent. There was no support for the hypothesis that these dramatic and continuous group changes were related to foraging success. Instead, we speculated that these group changes perhaps were designed to maintain cohesion among a membership that was spread over a wide area. We also examined if associates species may be more than just passive followers of core species but rather instigated the attracting or the building of core groups. Both associate species do attract striped parrotfish in open areas and thus appear active in initiating mixed-species groups. Finally, given that associate species seem to derive little foraging benefit from following core species, we tested the hypothesis that associate species joined core groups to gain protection against predators. Associate species do not selectively join the larger groups of striped parrotfish but appear to join core species randomly and the groups they joined resembled the wide assortment of core groups available in the area. Thus, while associates may be joining core groups for protection, this 展开更多
关键词 Caribbean Parrotfish Scarus Sparisoma Surgeonfish Acanthurus
下载PDF
Chest Irradiation Associated Cardio-Vascular Disease
5
作者 Malka Yahalom Ehud Rozner +2 位作者 Menachem Nahir Lev bloch Yoav Turgeman 《World Journal of Cardiovascular Diseases》 2016年第6期179-187,共9页
Background: The heart and great vessels were once thought to be relatively resistant to the damaging effect of radiation therapy. There is now clear evidence that thoracic irradiation may cause acute inflammation and ... Background: The heart and great vessels were once thought to be relatively resistant to the damaging effect of radiation therapy. There is now clear evidence that thoracic irradiation may cause acute inflammation and progressive fibrosis of different structures, including the heart valves, the myocardium and the pericardium, the coronary arteries and the conduction system. As new therapies have improved survival, many patients with cancer (mostly Hodgkin’s disease and breast cancer) are now at risk of cardiovascular (CV) complications following radiation therapy. Objectives: To raise awareness of CV complications following chest irradiation. Method: We present 5 patients that we treated during a short period of time (between June 2013 (6/2013) and February 2015 (2/2016)), who suffered CV involvement that needed therapy, following chest irradiation. Conclusions: Patients after chest irradiation should be followed periodically, in order to diagnose and treat CV complications, in time. 展开更多
关键词 Chest Irradiation Cardiovascular Involvement
下载PDF
Delayed presentation of a loose body in undisplaced paediatric talar neck fracture 被引量:2
6
作者 Vishal Patel Benjamin bloch +1 位作者 Nicholas Johnson Jitendra Mangwani 《World Journal of Orthopedics》 2014年第3期398-401,共4页
Fractures of the talus are rare in children.A high index of suspicion is needed to avoid missing such an injury,which is not an uncommon occurrence especially with undisplaced fractures.We present an unusual case of a... Fractures of the talus are rare in children.A high index of suspicion is needed to avoid missing such an injury,which is not an uncommon occurrence especially with undisplaced fractures.We present an unusual case of an undisplaced talar neck fracture in a five-year-old child leading to a delayed presentation of a symptomatic osteochondral loose body in the ankle joint.To our knowledge there are no reports in the literature of osteochondral loose bodies occurring in conjunction with an associated undisplaced talar neck fracture in either children or adults.The loose body was removed using anterior ankle arthroscopy.The child had an uneventful post operative recovery and regained full range of movement and function of his ankle joint and was discharged at one year follow-up.We aim to highlight the need to have a low threshold to further evaluate symptomatic children after fracture healing of an undisplaced talar neck fracture for a possible associated loose bodyin the ankle joint. 展开更多
关键词 TALUS Fracture LOOSE BODY ANKLE ARTHROSCOPY Children
下载PDF
Loss of Aβ-nerve endings associated with the Merkel cell-neurite complex in the lesional oral mucosa epithelium of lichen planus and hyperkeratosis 被引量:2
7
作者 Daniela Calderon Carrion Yiiksel Korkmaz +4 位作者 Britta Cho Marion Kopp Wilhelm bloch Klaus Addicks Wilhelm Niedermeier 《International Journal of Oral Science》 SCIE CAS CSCD 2016年第1期32-38,共7页
The Merkel cell-neurite complex initiates the perception of touch and mediates Ap slowly adapting type I responses. Lichen planus is a chronic inflammatory autoimmune disease with T-cell-mediated inflammation, whereas... The Merkel cell-neurite complex initiates the perception of touch and mediates Ap slowly adapting type I responses. Lichen planus is a chronic inflammatory autoimmune disease with T-cell-mediated inflammation, whereas hyperkeratosis is characterized with or without epithelial dysplasia in the oral mucosa. To determine the effects of lichen planus and hyperkeratosis on the Merkel cell-neurite complex, healthy oral mucosal epithelium and lesional oral mucosal epithelium of lichen planus and hyperkeratosis patients were stained by immunohistochemistry (the avidin-biotin-peroxidase complex and double immunofluorescence methods)using pan cytokeratin, cytokeratin 20 (K20, a Merkel cell marker), and neurofilament 200 (NF200, a myelinated Aβ- and Aδ-nerve fibre marker) antibodies. N F200-immunoreactive (ir) nerve fibres in healthy tissues and in the lesional oral mucosa epithelium of lichen planus and hyperkeratosis were counted and statistically analysed. In the healthy oral mucosa, K20-positive Merkel cells with and without close association to the intraepithelial NF200-ir nerve fibres were detected. In the lesional oral mucosa of lichen planus and hyperkeratosis patients, extremely rare NF200-ir nerve fibres were detected only in the lamina propria. Compared with healthy tissues, lichen planus and hyperkeratosis tissues had significantly decreased numbers of NF200-ir nerve fibres in the oral mucosal epithelium. Lichen planus and hyperkeratosis were associated with the absence of Aβ-nerve endings in the oral mucosal epithelium. Thus, we conclude that mechanosensation mediated by the Merkel cell-neurite complex in the oral mucosal epithelium is impaired in lichen planus and hvperkeratosis. 展开更多
关键词 Aβ-nerve fibres HYPERKERATOSIS lichen planus MECHANOSENSATION Merkel cell-neurite complex
下载PDF
3,4,5-三甲氧基溴苯的合成 被引量:2
8
作者 史鸿鑫 林辉 +2 位作者 Mandvill Grad bloch Robert 刘化章 《精细化工》 EI CAS CSCD 北大核心 2001年第8期453-455,共3页
比较了几种 3,4,5 三甲氧基溴苯 (BTMOB)的合成方法。 3,4,5 三甲氧基苯胺 (TMOA)经重氮化和Sandmeyer法合成 ,BTMOB的收率较高。确定了最佳反应条件 :n(ArNH2 )∶n(NaNO2 )∶n(NaBr) =1 0∶1 2∶1 5 ,重氮化反应温度低于 5℃ ,重氮... 比较了几种 3,4,5 三甲氧基溴苯 (BTMOB)的合成方法。 3,4,5 三甲氧基苯胺 (TMOA)经重氮化和Sandmeyer法合成 ,BTMOB的收率较高。确定了最佳反应条件 :n(ArNH2 )∶n(NaNO2 )∶n(NaBr) =1 0∶1 2∶1 5 ,重氮化反应温度低于 5℃ ,重氮化络合物分解时 ,回流 1h ,BTMOB的收率可达 87 5 %。 展开更多
关键词 三甲氧基溴苯 三甲氧基苯胺 Sandmeyer反应 合成
下载PDF
MODELING COMMERCIAL PROCESSES AND CUSTOMER BEHAVIORS TO ESTIMATE THE DIFFUSION RATE OF NEW PRODUCTS 被引量:2
9
作者 Alain bloch Daniel KROB Ada Suk-Fung NG 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2005年第4期436-453,共18页
This paper presents a generic mathematical model for depicting the diffusion of an innovative product on a given market. Our approach relies on a probabilistic modeling of each customer behavior with respect to the co... This paper presents a generic mathematical model for depicting the diffusion of an innovative product on a given market. Our approach relies on a probabilistic modeling of each customer behavior with respect to the commercial process which is used to promote such a product. We introduce in particular the concept of coherent market that corresponds to a market which can be analyzed in a uniform way within our model. This last notion allows us to recover the classical empirical results that were discovered and widely studied by E.M. Rogers and his school. We explain finally how to use our approach as a support for analytic predictive marketing. 展开更多
关键词 Analytic marketing coherent market commercial process customer behavior diffusion of innovations Markovian model probabilistic modeling waiting time
原文传递
Comparisons of Group-Size, Composition and Movement of Herbivorous Reef Fish in Jamaica and Grand Cayman Island 被引量:1
10
作者 Layla Al-Shaer Andrew bloch +2 位作者 Matthew Draud Brandon Baumann Murray Itzkowitz 《Open Journal of Marine Science》 2020年第1期1-15,共15页
The decline in herbivorous fishes is an important contributing factor to the degradation of coral reefs, because their reduction contributes to macro algae overgrowth, which can have harmful effects on corals. Herbivo... The decline in herbivorous fishes is an important contributing factor to the degradation of coral reefs, because their reduction contributes to macro algae overgrowth, which can have harmful effects on corals. Herbivorous fish often form mixed-species groups to locate foraging sites and for defense. The movements and compositions of these groups are dependent on the relative numbers of different species present. Some species, such as the striped parrotfish (Scarus iserti) and ocean surgeonfish (Acanthurus bahianus), serve as core species that lead mixed-species groups. Others, such as the redband (Sparisoma aurofrenatum) and stoplight parrotfishes (Sparisoma viride), follow core species as their associates. Despite the potential importance and abundance of mixed-species groups on reefs, little attention has been given to their composition and movements. Our intent was to determine whether the social dynamics of mixed-species groups in Jamaica were similar to those of Grand Cayman. The overall sizes of mixed-species groups were smaller in Grand Cayman. Focal striped parrotfish in Grand Cayman formed smaller groups, changed composition less, and moved less frequently than in Jamaica. Although probably more abundant than striped parrotfish, the ocean surgeonfish in Grand Cayman did not function as a core species but rather attached themselves as associates to the smaller striped parrotfish groups. Redband parrotfish moved less often in Grand Cayman, and appeared to be more dependent on striped parrotfish groups than stoplight parrotfish. While previous studies on herbivorous reef fish have shown that changes in foraging patterns can change with location, perhaps related to structural heterogeneity and resource distribution, this study illustrates that social interactions between common members of mixed-species groups also change. We suggest that the intra and interspecific social interactions in Grand Cayman are less attuned to finding erratically located high quality resources than those in Jamaica. Other plausible 展开更多
关键词 CORAL Decline FORAGING Behavior Algae-Grazing HERBIVORE SCARIDAE Acanthuridae
下载PDF
Accuracy and Consistency of Respiratory Inductive Plethysmography for Overnight Tidal Volume Measurement 被引量:1
11
作者 张劲农 Eric W Ruch Konrad E bloch 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2001年第1期35-37,58,共4页
To validate the accuracy and consistency of respiratory inductive plethysmography (RIP) in measuring tidal volume after an overnight sleep, tidal volumes of 18 patients with suspected sleep disordered breathing and 8... To validate the accuracy and consistency of respiratory inductive plethysmography (RIP) in measuring tidal volume after an overnight sleep, tidal volumes of 18 patients with suspected sleep disordered breathing and 8 normal volunteers were measured simultaneously with RIP (V TRIP ) and with an ultrasonic airflow meter (V TUFM ) before and after an unstrained overnight sleep on supine and lateral decubitus. The bias of the V TRIP was expressed as (V TRIP V TUFM )/ V TUFM ·100 %, limits of agreement between V TRIP and V TUFM was measured by averaged bias ±2 s . Results showed that in normal subjects, the bias of RIP before and after overnight sleep was precise and consistent in both supine (0.7 % and -1.6 %) and lateral decubitus (3.7 % and -0.56 %). In these patients, the bias of RIP before and after sleep in supine also remained small (1.9 % and 1.7 %), but it became larger in lateral decubitus (24.5 % and 20.4 %) and 11.5 % exceeded the limits of agreement observed in the evening. The patients′ body mass indices (BMI) were higher than those of normal subjects (median 34.2 vs. 27.8 kg/m 2). Pooled data showed that the bias of V TRIP in the morning on lateral decubitus but not on supine was correlated to BMI (Spearman R=0.32, n =52, P =0.02). Thus, we were led to conclude that the accuracy of V TRIP overnight was precise and consistent in normal subjects, but the deviation of V TRIP measured on lateral decubitus in patients especially in those with excessive obesity was greater, thus, the method should not be used for quantitative determination. 展开更多
关键词 sleep study respiratory inductive plethysmography (RIP) tidal volume
下载PDF
顺式-和反式-2,5-二取代四氢呋喃的立体选择性合成 被引量:1
12
作者 史鸿鑫 刘化章 +2 位作者 bloch R. Mandville G. 林辉 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2003年第5期831-836,共6页
内酯与有机锂试剂发生亲核加成反应,再在酸催化下用NaBH_3CN还原,反应的立体选择性可能是由氢负离子在中间体氧鎓离子位阻最小的一侧进攻所引起.所得的三环化合物经热分解和加氢反应,制备顺式和反式-2,5-二取代四氢呋喃。
关键词 顺式-2 5-二取代四氢呋喃 反式-2 5-二取代四氢呋喃 立体选择性合成 内酯 有机锂试剂 亲核加成反应 酸催化还原 aBH2CN 拮抗血小板活化因子作用
下载PDF
好书榜Java专题
13
作者 Joshua bloch 潘爱民 《程序员》 2003年第11期122-124,共3页
Java领域犹如一座“魔法森林”,产品云集,概念纷繁。幸好本期请到了热心的专家的指路:他们是“守林人”,常在林中窗行,晓得途中的难点与捷径。有了他们的指引,开发者能概览这座魔法森林的拓扑学,……
关键词 JAVA 森林 EJB JZEE 魔法 拓扑学 几何学 出版社 文化机构
下载PDF
Endovascular approach to acute aortic trauma
14
作者 Riyad Karmy-Jones Desarom Teso +2 位作者 Nicole Jackson Lisa Ferigno Robert bloch 《World Journal of Radiology》 CAS 2009年第1期50-62,共13页
Traumatic thoracic aortic injury remains a major cause of death following motor vehicle accidents.Endovascular approaches have begun to supersede open repair,offering the hope of reduced morbidity and mortality.The av... Traumatic thoracic aortic injury remains a major cause of death following motor vehicle accidents.Endovascular approaches have begun to supersede open repair,offering the hope of reduced morbidity and mortality.The available endovascular technology is associated with specific anatomic considerations and complications.This paper will review the current status of endovascular management of traumatic thoracic aortic injuries. 展开更多
关键词 AORTA COMPLICATIONS Outcomes TRAUMATIC ENDOVASCULAR
下载PDF
砂岩孔隙度和渗透率的经验法预测
15
作者 bloch,S 刘震 《世界石油科学》 1993年第2期24-31,共8页
关键词 渗透率 砂岩 孔隙度 预测
下载PDF
砂岩孔隙度和渗透率的经验预测
16
作者 bloch,S 涂阳发 《石油勘探开发情报》 1992年第6期26-40,12,共16页
关键词 砂岩 孔隙度 渗透率 预测
下载PDF
未来20年的车辆碰撞测试
17
作者 Byron bloch 《汽车与配件》 2009年第9期20-21,共2页
我们可以预期,到2028年,无论是车辆技术还是由汽车制造商和政府机构进行的碰撞测试,都会出现许多新事物。
关键词 碰撞测试 车辆技术 汽车制造商 政府机构
下载PDF
High Energy Heavy Ion Irradiation Induced Thermal Spike in Pure Metals
18
作者 Wang Zhiguang Ch.Dufour E. Paurllierl and M. Toulerllonde(LERMAT,ISMRa, URA CNRS 1317 CampusⅡ, Bd Marechal Juin, 14050 Caen Cedex, France. CIRIL, UMR CEA-CNRS, rue Claude bloch, 5133,14040 Caen Cedex, France.) 《IMP & HIRFL Annual Report》 1996年第1期175-176,共2页
HighEnergyHeavyIonIrradiationInducedThermalSpikeinPureMetals¥WangZhiguang;Ch.Dufour;E.PaurllierlandM.Toulerl... HighEnergyHeavyIonIrradiationInducedThermalSpikeinPureMetals¥WangZhiguang;Ch.Dufour;E.PaurllierlandM.Toulerllonde(LERMAT,ISMR... 展开更多
关键词 SPIKE
下载PDF
以家族企业为榜样
19
作者 Alain bloch 《经理人》 2013年第1期58-59,共2页
在很多人看来,“家族企业”四个字就意味着一间小型或中型的公司,只关注本地生意,还面临着一系列通病,比如为了继承权吵得不可开交。有很多夫妻店的确是这个样子,但这个形象并没有反映出家族企业在世界经济中扮演的强大角色。家族... 在很多人看来,“家族企业”四个字就意味着一间小型或中型的公司,只关注本地生意,还面临着一系列通病,比如为了继承权吵得不可开交。有很多夫妻店的确是这个样子,但这个形象并没有反映出家族企业在世界经济中扮演的强大角色。家族企业中不仅有像沃尔玛、三星、塔塔集团和保时捷这样的商界巨头,销售额极高的也不在少数:根据波士顿咨询公司的分析,在销售额超过10亿美元的企业中,30%以上都是家族企业。 展开更多
关键词 家族企业 波士顿咨询公司 榜样 世界经济 塔塔集团 销售额 继承权 夫妻店
原文传递
β_1整合素基因缺失对G_i蛋白分布的影响
20
作者 韩捷 Wilhel m bloch +1 位作者 Michael Welthar Klaus Addicks 《第四军医大学学报》 北大核心 2001年第15期1345-1348,共4页
目的 了解跨膜蛋白 β1整合素对信号分子G蛋白细胞内构型的影响 ,为进一步研究 β1整合素在信号传导中的作用打下基础 .方法 采用荧光双标记及重叠合显微镜分析技术 ,观察野生型胚胎干细胞系 (D3细胞 ) ,β1整合素基因敲除胚胎干细胞 ... 目的 了解跨膜蛋白 β1整合素对信号分子G蛋白细胞内构型的影响 ,为进一步研究 β1整合素在信号传导中的作用打下基础 .方法 采用荧光双标记及重叠合显微镜分析技术 ,观察野生型胚胎干细胞系 (D3细胞 ) ,β1整合素基因敲除胚胎干细胞 (G2 0 1细胞 ) ,β1整合素基因敲除后再植入胚胎干细胞 (G2 0 1N)及小鼠胚胎心肌细胞中多种G蛋白 (Gαs,Gαi1-3 ,Gαo,Gαi/o/t/z)细胞内构型特点和差异 .结果 Gαs,Gαo,Gαi/o/t/z在上述几种细胞系中均呈弥漫性分布 ,未能发现明显差异 ,与此不同的是Gαi1-3 在D3细胞源性心肌细胞内呈网状分布 ,在非心肌细胞内呈线条状分布 ,而在G2 0 1细胞中Gi 上述特异性构型被打乱 ,呈近似于弥漫样分布 ,值得注意的是在β1整合素基因重新恢复的G2 0 1N细胞Gi构型又呈网样或线条样分布 ,与野生型胚胎干细胞中Gi 的构型相一致 .结论 β1整合素能够影响信号分子Gi蛋白的细胞内定位 ,推测β1整合素可通过改变Gi 的分布而影响Gi 展开更多
关键词 Β1整合素 G蛋白 信号分子 基因缺失 信号传导
下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部