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991.
建立适应我国国情的高效双向转诊机制,对于推进我国的医疗体制改革具有至关重要的作用。本文通过对中西方现行卫生制度的对比,结合我国有中国特色的社会主义国家的国情,对我国的卫生制度中存在的问题进行了深入剖析,探讨如何才能有效地实现高效的双向转诊。目前,我国医疗卫生事业的问题覆盖多个方面:主要表现在医疗资源,医院管理,在岗医护人员的个人职业素质,卫生部门的监管,医疗资源的大量浪费,医院分级不平衡另多数患者普遍选择三级医院就诊,而选择二级以下医院就诊的患者则较少。如何在符合我国国情的基础上改变我国的医疗卫生现状、满足人民群众不断提高的医疗服务需求是我国医疗改革亟待解决的问题。建立高效率的双向转诊制度势在必行。目前,在双向转诊中遇到的问题:1.传统理念导致的对各级医疗机构职能的理解上存在偏差,2.医疗机构自身定位不明确,3.双向转诊制度的各项相关配套政策不完善,4.双向转诊制度的社会认同度低。高效双向转诊机制建立以后,可以节省大量的医疗资源,减少了不必要的浪费,推进了医疗资源的合理配置,减少了因地区差异引起的治疗时机延误,高效的双向转诊制度会使医疗卫生资源配置进一步优化、还可以加强医疗机构之间的协作、降低医疗费用支出、促进社区卫生服务迅速发展等有重大的意义。 相似文献
992.
Siliceous hot spring deposits form at Earth's surface above terrestrial hydrothermal systems, which create low‐sulphidation epithermal mineral deposits deeper in the crust. Eruption of hot spring waters and precipitation of opal‐A create sinter apron complexes and areas of geothermally influenced wetland. These provide habitat for higher plants that may be preserved in situ, by encrustation of their surfaces and permineralization of tissues, creating T0 plant assemblages. In this study, we review the fossil record of hot spring floras from subfossil examples forming in active hot spring areas, via fossil examples from the Cenozoic, Mesozoic and Palaeozoic to the oldest known hot spring flora, the Lower Devonian Rhynie chert. We demonstrate that the well‐known megabias towards wetland plant preservation extends to hot spring floras. We highlight that the record of hot spring floras is dominated by plants preserved in situ by permineralization on geothermally influenced wetlands. Angiosperms (members of the Cyperaceae and Restionaceae) dominate Cenozoic floras. Equisetum and gleicheniaceous ferns colonized Mesozoic (Jurassic) geothermal wetlands and sphenophytes and herbaceous lycophytes late Palaeozoic examples. Evidence of the partitioning of wetland hydrophytic and dryland mesophytic communities, a feature of active geothermal areas, is provided by well‐preserved and well‐exposed fossil sinter apron complexes, which record flooding of dryland environments by thermal waters and decline of local forest ecosystems. Such observations from the fossil record back‐up hypotheses based on active hot springs and vegetation that suggest removal of taphonomic filtering in hot spring environments is accompanied by an increase in ecological and ecophysiological filtering. To this end we also demonstrate that in the hot spring environment, the wetland bias extends beyond broad ecology. We show that ecosystems preserved from the Cenozoic to the Mesozoic provide clear evidence that the dominant plants preserved in situ by hot spring activity are also halophytic, tolerant of high pH and high concentrations of heavy metals. By extension, we hypothesize that this is also the case in Palaeozoic hot spring settings and extended to the early land plant flora of the Rhynie chert. 相似文献
993.
Manja Coopmans 《Ethnic and racial studies》2013,36(12):2037-2054
This paper studies to what extent participating in days for national commemoration and celebration is associated with feelings of national belonging, and to what extent this is comparable across generations and ethnic groups. Utilizing data from a national survey (N = 4,505), three major national days in the Netherlands are examined. We find that whereas participation in Queen's Day is associated with national belonging for all generations, for Remembrance Day this holds only for the generation born between 1945 and 1955, and for Liberation Day for the generations born after 1955. Moreover, for citizens with a non-Western origin, participating in national days is associated with national belonging more strongly than for citizens with a native Dutch or other Western background. These findings highlight the importance of paying attention to potential group differences in the association between participation in national days and feelings of national belonging. 相似文献
994.
Merlin Schaeffer 《Ethnic and racial studies》2013,36(1):156-178
Abstract Why and under which conditions do people employ ethnic categories rather than others (such as age, class, gender, and so on) to conceptually organize their social environment? This article analyses an open-ended question on who is seen as responsible for neighbourhood problems taken from a recently conducted large-scale survey in Germany. By doing so, this study tries to give novel insight on native Germans' use of ethnic folk classifications and aims to identify contextual factors that might explain why people characterize problem-groups in ethnic terms. This article shows that drunkards, the elderly and especially teenagers are seen as problem-groups more frequently than any ethnic minority. Conditions of economic decline and out-group size are analysed as to whether they are associated with a higher likelihood of using ethnic categories. The findings suggest that the effects of out-group size are diminishing in their impact, whereas the effects of economic decline are accumulating in strength. 相似文献
995.
996.
扁杆藨草(Scirpus planiculmis)和三江藨草(S.nipponicus)的球茎是迁徙白鹤(Grus leucogeranus)在莫莫格中途停歇地的主要食物。2010年9月15~25日,对莫莫格白鹤集中停歇地鹅头泡湿地的20条样线上100 m等间隔470个取样点进行了地下0~20 cm的藨草球茎的取样工作。基于此,采用反距离权重、4种径向基函数和普通克里格共6种空间插值方法模拟了该区域藨草球茎密度。交叉验证和插值结果的空间分布图对比,径向基函数中的张力样条插值效果最佳,是最适于该区域挺水植物藨草球茎密度的空间插值方法。张力样条插值结果表明:研究区内藨草球茎密度均值为(46.0±44.3)个/m2。其中,<25个/m2的面积占研究区的41.7%,25~100个/m2的面积占45.9%,而>100个/m2的面积仅占12.4%。研究结果为下一步分析白鹤迁徙种群与环境因子的生态关系、预测该地区白鹤的环境容纳量提供十分重要的基础数据。 相似文献
997.
采用涡度相关法,对2011年生长季的黄河三角洲芦苇湿地净生态系统CO2交换(NEE)进行了观测,研究湿地NEE的变化规律及其影响因子.结果表明: 不同月份芦苇湿地的NEE日变化均呈“U”形曲线,CO2最大净吸收率和释放率的日均值分别为(0.44±0.03)和(0.16±0.01) mg CO2·m-2·s-1;芦苇湿地NEE、生态系统呼吸(Reco)、总初级生产力(GPP)的季节变化均呈现生长旺季(7-9月)较高、生长初期(5-6月)和生长末期(10-11月)较低的趋势;Reco和NEE在8月达到峰值,GPP在7月达到峰值.芦苇湿地生态系统的CO2交换受到光合有效辐射(PAR)、土壤温度(Ts)和土壤体积含水量(SWC)的共同影响.白天NEE与PAR呈直角双曲线关系;5 cm深处Ts与夜间生态系统呼吸(Reco,n)呈指数关系,生态系统呼吸的温度敏感性(Q10)为2.30,SWC和Ts是影响芦苇湿地Reco,n的主要因子.在整个生长季,黄河三角洲芦苇湿地生态系统是一个明显的CO2的汇,总净固碳量为780.95 g CO2·m-2. 相似文献
998.
盐城海滨湿地景观演变关键土壤生态因子与阈值研究 总被引:2,自引:0,他引:2
文章以盐城海滨湿地典型区域为案例,以2011年4月和2012年4月对海滨湿地土壤数据为基础,结合2011年ETM 遥感影像,运用灰色关联分析、线性回归模拟和地统计学方法,辨识海滨湿地景观演变的关键生态因子,并确定其生态阈值。得出基本结论如下:(1)海滨湿地土壤理化性质海陆差异明显:从米草沼泽—碱蓬沼泽—芦苇沼泽,土壤水分和盐度表现出递减的趋势;土壤有机质、营养盐总体上从米草沼泽—碱蓬沼泽—芦苇沼泽,表现出两头高中间低的特征;湿润年份土壤水分高于干旱年份,湿润年份土壤盐度低于干旱年份。(2)灰色关联分析表明:干旱年份,水分>盐度>铵态氮>速效钾>有机质>有效磷;湿润年份为:盐度>水分>有效磷>铵态氮>速效钾>有机质,因此把土壤水分和盐度确定为海滨湿地景观演变的关键生态因子。(3)土壤水分和盐度在东西海陆方向上的变异大于南北海岸延伸方向上的变异。(4)将景观类型图和海滨湿地土壤水分与盐度分异图叠加分析,得出:芦苇滩土壤水分阈值<42.332%,盐度阈值<0.745%;碱蓬滩土壤水分阈值为38.836%~46.593%,盐度阈值为0.403%~1.314%;米草滩土壤水分阈值>39.475%,盐度阈值>0.403%;光滩的土壤阈值>41.550%,盐度阈值>0.656%。 相似文献
999.
David L. Otis William R. Crumpton David Green Anna Loan‐Wilsey Tom Cooper Rex R. Johnson 《Restoration Ecology》2013,21(2):276-284
Justification for investment in restored or constructed wetland projects are often based on presumed net increases in ecosystem services. However, quantitative assessment of performance metrics is often difficult and restricted to a single objective. More comprehensive performance assessments could help inform decision‐makers about trade‐offs in services provided by alternative restoration program design attributes. The primary goal of the Iowa Conservation Reserve Enhancement Program is to establish wetlands that efficiently remove nitrates from tile‐drained agricultural landscapes. A secondary objective is provision of wildlife habitat. We used existing wildlife habitat models to compare relative net change in potential wildlife habitat value for four alternative landscape positions of wetlands within the watershed. Predicted species richness and habitat value for birds, mammals, amphibians, and reptiles generally increased as the wetland position moved lower in the watershed. However, predicted average net increase between pre‐ and post‐project value was dependent on taxonomic group. The increased average wetland area and changes in surrounding upland habitat composition among landscape positions were responsible for these differences. Net change in predicted densities of several grassland bird species at the four landscape positions was variable and species‐dependent. Predicted waterfowl breeding activity was greater for lower drainage position wetlands. Although our models are simplistic and provide only a predictive index of potential habitat value, we believe such assessment exercises can provide a tool for coarse‐level comparisons of alternative proposed project attributes and a basis for constructing informed hypotheses in auxiliary empirical field studies. 相似文献
1000.
1. Floodplains and their water bodies are typical ecotopes of large lowland rivers. The lowland Oder River, Germany, provided a rare opportunity to study fish assemblages of comparable floodplain water bodies differing by >50 years of isolation history. We hypothesised that true floodplain specialists peak in rarely connected water bodies, while frequently flooded waters support tolerant generalists. 2. Three macrohabitats, main channel (MC), temporarily connected and isolated floodplain water bodies, were sampled by electro‐fishing and their fish assemblage characters recorded. 3. Long‐term isolation of floodplain water bodies had a significant effect on the fish assemblage by promoting species preferring still water. Limnophilic and floodplain specialist species significantly increased with isolation. 4. Fish densities, species richness and diversity clearly differed between MC sites and floodplain water bodies. Shannon’s species diversity index peaked in both the MC and isolated waters and was lowest in the temporarily flooded waters where eurytopic fish dominated. 5. The significant gain in abundance and numbers of limnophilic species in the isolated compared to the temporarily flooded water bodies underpinned the significant contribution of long‐term isolated waters to the gamma‐diversity of large floodplain rivers, which should be considered in floodplain rehabilitation. 相似文献