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91.
目的:观察洛哌丁胺对大鼠慢传输型便秘模型稳定性的影响。方法:将20只大鼠随机分成对照组、模型组、模型维持组、治疗组,每组各5只。模型组、模型维持组、治疗组予洛哌丁胺混悬液灌胃,对照组以等体积的0.9%氯化钠注射液灌胃,连续6 d。造模第7天开始模型维持组继续予洛哌丁胺混悬液灌胃,治疗组灌胃莫沙必利混悬液,对照组及模型组灌胃等体积0.9%氯化钠注射液。观察大鼠造模前、造模6d和干预6d后的一般情况、6 h粪便粒数及重量、粪便含水率及大肠墨汁推进率。结果:造模6 d后大鼠出现活动减少,采食减少,毛发枯萎脱落,尿黄,大便数量及含水量减少;模型组造模停止6 d后及治疗组干预后大鼠一般情况改善,采食量、体质量增长,粪便粒数、粪便含水率均增加。各组大鼠6 h粪便粒数、重量、含水量方面,造模6d后,模型组、模型维持组、治疗组与对照组组间比较及造模前后组内比较,差异均有统计学意义(P<0.05);对照组、模型组、治疗组与模型维持组比较,差异均有统计学意义P<0.05);治疗组、模型维持组、模型组干预6d后与造模6d后比较,差异均有统计学意义(P<0.05)。对照组、模型组、治疗组与模型维持组大鼠大肠墨汁推进率比较,差异均有统计学意义(P<0.05)。结论:洛哌丁胺大鼠慢传输型便秘模型是一种相对简便的慢传输型便秘大鼠模型,模型停药后可自愈,需用药物维持模型的稳定性。  相似文献   
92.
BOOK REVIEWS     
Book Reviewed in this article: Introduction to Climatology for the Tropics . J. O. Ayoade. Conservation and Management of Natural Resources in the United States . Charles F. Bennett. The Keeping of Animals: Adaptation and Social Relations in Livestock Producing Communities . Riva Berleant-Schiller and Eugenia Shanklin, ed. The Evolution of Geographic Thought in America: A Kentucky Root Wilford A. Bladen and Pradyumna P. Karan, eds. Latin America: Geographical Perspectives , 2nd ed. Harold Blakemore and Clifford T. Smith, ed. The Rural Real Estate Market. Department of Geography Publication Series, No. 18 . Chris Bryant. Urban Geomorphology in Drylands . R. U. Cooke, D. Brunsden, J. C. Doornkamp, and D. K. C. Jones with contributions by J. Griffiths, P. Knott, R. Potter, and R. Russell. Italian Geography, 1960–1980. Meeting of the Status of the Geographic Research in Italy, 1960–1980. Treated under the auspices of Consiglio Nazionale delle Ricerche and organized by Istituto di Geografia Umana della Facoltà di Lettere e Filosofia dell'Università degli Studi di Milano , Giacomo Corna Pellecrini and Carlo Brusa, eds. The Changing Fenland . H. C. Darby. The Future for the City Centre . R. L. Davies and A. G. Champion, eds. Saudi Arabia, Energy, Developmental Planning, and Industrialization . Ragaei El Mallakh, Dorothea H. El Mallakh, eds. For We Are Sold, I and My People: Women and Industry in Mexico's Frontier . Maria Patricia Fernández-Kelly. The Great Lakes Forest: An Environmental and Social History . Susan L. Flader, ed. Regional Transformation and Industrial Revolution: A Geography of the Yorkshire Woolen Industry . Derek Gregory Crime in City Politics . Anne Heinz, Herbert Jacob and Robert L. Lineberry, eds. Revitalizing Cities . H. Briavel Holcomb and Robert A. Beauregard. Cartographic Relief Presentation . Eduard Imhof. H. J. Steward, Trans. Soviet Union: A Geographical Survey . S. V. Kalesnik and V. F. Pavlenko, ed. Cognition and Environment . Stephen Kaplan and Rachel Kaplan. Environmental Protection: The International Dimension . David A. Kay and Harold K. Jacobsen, eds. Mathematical Programming Methods for Geographers and Planners , James Killen. Gentrification Amid Urban Decline: Strategies for America's Older Cities . Michael H. Lang. The North Atlantic Sulphur System . Risto Laulajainen. The Jerusalem Cathedra: Studies in the History, Archaeology, Geography and Ethnography of the Land of Israel, Vol. 2 . Lee I. Levine ed. Jerusalem and Detroit: Recreation Planning and Management . Stanely R. Lieber and Daniel R. Fesenmaier, eds. Heartland and Hinterland: A Geography of Canada . L. D. McCann, ed. Scarborough Where We Live: The Residential Districts of Minneapolis and St. Paul . Judith A. Martin and David A. Lanegran. California: The Geography of Diversity . Crane S. Miller and Richard S. Hyslop. Palo Alto The Dilemma of Amazonian Development . Emilio F. Moran, ed. Boulder Nuclear Waste: Socioeconomic Dimensions of Long-Term Storage . Steve H. Murdock, F. Larry Leistritz, and Rita R. Hamm, eds. Boulder Communism and the Politics of Inequalities . Daniel N. Nelson, ed. The Los Angeles Metropolis . Howard J. Nelson. Dubuque An Historical Geography of Urban System Development: Tidewater Virginia in the 18th Century . James O'Mara. Procedures and Standards for a Multipurpose Cadastre . East Asia: Geographical and Historical Approaches to Foreign Area Studies . Clifton W. Pannell, ed. Dubuque Mackinder: Geography as an Aid to Statecraft . W. H. Parker. Beyond the Urban Fringe: Land Use Issues of Nonmetropolitan America . Rutherford H. Platt and George Macinko, eds. Recreation Geography of the USSR . V. S. Preobrazhensky and V. M. Krivosheyev, eds. Missouri: A Geography . Milton D. Rafferty The Invisible Farmers: Women in Agricultural Production . Carolyn E. Sachs. Cayman Islands Seashore Vegetation: A Study in Comparative Biogeography . Jonathan D. Sauer. Hillslope Materials and Processes . Michael J. Selby. Housing in Britain: The Post-War Experience . John R. Short The Study of Population: Elements, Patterns and Processes . George A. Schnell and Mark Stephen Monmonier. Columbus The Soviet Union: A Systematic Geography . Leslie Symons, ed. The Ottoman Slave Trade and Its Suppression . Ehud R. Toledano. The Impact of Recession on Industry, Employment and the Regions, 1976–1981 . Alan R. Townsend. Landslides and Their Control , 2nd ed. Quido Záruba and Vojtech Mencl. Translated from the Czech by H. Zárubová and V. Mencl.  相似文献   
93.
Twenty-six samples including roof, bottom and coal plies of a marine influenced coal bed were collected from the Antaibao mining district, Shanxi, China. The rare earth elements (REEs) were determined in solids and organic solvent extracts. The distribution pattern showed three distinct patterns: shale-like, LREE-rich and HREE-rich. This is attributed to the variable microenvironment of peat-forming swamp, the degree of marine influences and different REE sources. REEs in the coal are mainly controlled by detrital minerals but also affected by seawater. The chondrite-normalized REE patterns of the organic solvent extracts are distinctly different from those of corresponding original coal samples, which show a negative Eu anomaly, a depletion of middle REEs and an enrichment of HREEs. The LREEs in coal extracts are likely adsorbed by hydrogen-containing functional groups, and HREEs are likely bonded to carbon atoms.  相似文献   
94.
中国阿尔泰山和俄罗斯阿尔泰山均属于阿尔泰山脉的组成部分,地理上互相连接,地质上具有相似的古生代演化历史,同样都发育中生代花岗岩及伴生的稀有金属矿床。中国阿尔泰山和俄罗斯阿尔泰山的中生代花岗岩及其稀有金属矿床既表现出一定的相似性,也存在一定的差别。两地与稀有金属矿床有关的中生代花岗岩主要为S型花岗岩,属于非造山花岗岩类,但在俄罗斯阿尔泰山发育以岩珠和岩脉型钨-钼、锂-钽为主的稀有金属矿床,时限为晚三叠世和早侏罗世,而中国阿尔泰山则发育以花岗伟晶岩脉型锂-铍-铌-钽为主的稀有金属矿床,时限从晚三叠世到晚侏罗世。这些花岗岩具有相似的Sr- Nd同位素特征,但~(87)Sr/~(86)Sr初始比值变化很大,可能是岩浆-流体作用的结果,而变化较小的ε_(Nd)(t)值与富集地幔来源的岩浆基本相当,或者可以解释为幔源岩浆与地壳物质混合的结果。  相似文献   
95.
In this study we analyzed the chemical composition of hydrothermally altered dacite and basalt from the Kuroko mining area, northeastern Honshu, Japan, by REE (rare earth element). Features of rare earth element analyses include: (1) altered footwall dacite exhibits a negative Eu anomaly compared with fresh dacite, suggesting preferential removal of Eu2+ from the altered dacite via hydrothermal solutions, (2) altered hangingwall dacite and basalt and dacite and basalt adjacent to ore deposits exhibit positive Eu anomalies compared with fresh dacite and basalt, suggesting addition of Eu2+ from hydrothermal solutions, (3) LREE ratio (∑LREE/∑REE) from altered dacite of chlorite–sericite zone and K-feldspar zone show a negative relationship with δ18O, and La/Sm ratios show a positive correlation with the K2O index. These trends indicate the addition of light rare earth elements such as La to the altered dacite from hydrothermal solution and/or leaching of heavy rare earth elements such as Sm and Yb, (4) Principal component analysis (PCA) indicates that light rare earth elements enrichment is related to the formation of sericite zone near the Kuroko deposits but not to the formations of chlorite and K-feldspar zones, and (5) The correlations among REE features (LREE ratio, MREE ratio, HREE ratio, Eu/Eu?), δ18O and K2O index are not found for montmorillonite zone, mixed layer clay mineral zone and mordenite zone. Therefore, it is inferred that sericite, chlorite and K-feldspar alterations are related to the Kuroko and vein-type mineralization, but montmorillonite and mordenite alterations are not related to the mineralizations, and probably they formed at the post-mineralization stage.  相似文献   
96.
Twenty-eight soil samples collected from the Nam Co Basin, Tibetan Plateau, have been analyzed for heavy metals (Cd, Cr, Ni, Cu, Zn, Pb and Mn), arsenic (As) and rare earth elements (REEs). In addition, for establishing the basic physio-chemical characteristics of the soil, pH, total organic concentration, electrical conductivity, and effective cation exchange capacity were measured. The results indicate that soil in the Nam Co Basin is still at an early alkaline weathering stage (pH = 7.94). Mean concentrations of heavy metals and As decreased as follows: Mn > Cr > Zn > Pb > Ni > Cu > As > Cd. The values of Cd, Cr, As, Pb and REEs in soil from the Nam Co Basin are higher relative to averaged background values over China. The chondrite-normalized diagrams of REEs suggest high REE(ΣLa → Eu)—enrichment, HREE(ΣGd → Lu)—depletion and Eu—depletion. Vertical profiles indicate that both heavy metals (except As) and REEs primarily exist in the surface soil. However, heavy metals and REEs vary in the surface soil between the southern and the northern bank of Nam Co. These differences are controlled mainly by parent materials.  相似文献   
97.
Cultural geographers often ascribe early animal domestications to the spiritual propitiation practices of ancient peoples, an interpretation that is not widely shared. This paper evaluates the sacrifice theory against Near Eastern archaeological data and refutes the idea that ritual sacrifice could have induced the earliest animal domestications of the Near East. The earliest domestications were the outcome of essentially ecological and economic processes which later gave rise to the sacrificial practices referred to by cultural geographers.  相似文献   
98.
稀土元素已被公认为是判断岩石物质来源的有效地球化学指示剂:而物源,尤其是含矿层的物源(有时包括成矿组分的来源)对区域成矿远景评价具有很重要的意义。本文主要从稀土元素地球化学角度研究了中条山上太古界涑水杂岩、下元古界绛县群、含矿层中条群篦子沟组代表性岩石的物质来源,并从物源(矿源)对含矿层的成铀、成铜远景进行了评价。指出了铀、铜成矿的有利地段。  相似文献   
99.
河流稀土元素地球化学研究进展   总被引:30,自引:1,他引:30  
河流系统中,稀土元素(REE)受区域地质背景、风化作用、溶液化学以及水与颗粒物相互作用等因素的影响发生分异。河流悬浮物显示轻稀土(LREE)适度富集;河水显示重稀土(HREE)富集,或在HREE富集的基础上又有适度的中稀土(MREE)富集;与其它微量元素相比,REE在河水与颗粒物之间有较小的分配系数(K≈10-6);河流沉积物多显示平坦的REE配分模式。  相似文献   
100.
吴亚楠  代晶晶  周萍  王俊华 《地质论评》2016,62(S1):411-412
离子吸附型稀土矿是1969年在我国江西赣南地区发现的一种新型外生矿物,具有储量丰富、稀土配分齐全、开采工艺简单等特征,是我国特有的宝贵资源,广泛应用于机械、农林、化工及航空航天等领域(王登红等,2013;邓茂春等,2013;代晶晶等,2013)。随着稀土需求量的不断增加,稀土越界开采和盗采现象时有发生,一些不法商人为了牟取暴利,罔顾环境,采取不当的开采方式,导致稀土矿区出现一系列环境问题(罗才贵等,2014;彭燕等,20016),严重影响矿区的生态环境。遥感作为一种新兴的监测技术,被广泛应用于矿山开发调查与监测中,而大量的高分辨率遥感数据的出现,也为矿山遥感监测工作提供了数据保障(王龙飞,2014)。本文在前人研究的基础上,采用国产高分一号数据,以江西寻乌稀土矿区为例,开展了稀土矿山环境问题遥感监测研究,展示了高空间分辨率遥感技术在稀土矿山监测中的应用优势,为相关部门提供技术支持和决策依据。  相似文献   
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