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291.
An eight-year-old neutered male diabetic Cardigan Welsh Corgi was presented for bilateral mature cataracts. Phacoemulsification and intraocular lens implantation were performed routinely, and recovery was uneventful for several months except for lipemic aqueous flare which gradually resolved during the postoperative period. Five months following surgery the owner presented the dog for decreased vision. White retinal deposits were visualized ophthalmoscopically. Serum analysis revealed that the dog was concurrently markedly hyperlipemic. The patient's diet was changed from a high- to a low-fat diet, following which diabetes control improved, hyperlipemia resolved, and the retinal deposits decreased markedly in size. The retinal deposits seen ophthalmoscopically are presumed to be lipid based upon their association with marked hyperlipemia, and the concurrent resolution of hyperlipemia and the fundic lesions.  相似文献   
292.
中国草地生态系统碳循环研究进展   总被引:5,自引:2,他引:5  
草地生态系统碳循环研究在揭示草地碳源/汇功能,提高草地碳管理水平上至关重要。阐述了碳科学的重要意义;对我国草地生态系统碳储量及碳排放量评估结果予以总结比较;探讨工程建设、草原开垦、放牧管理、施肥、草地恢复技术和气候变化及其他自然因素对草地生态系统碳循环的影响;概括并评价目前我国草地生态系统碳评估的研究方法及意义。指出目前我国草地生态系统碳循环研究中存在的主要问题,及未来中国草地生态系统碳循环的研究趋势。  相似文献   
293.
农牧交错带小流域防护林水源涵养功能研究   总被引:2,自引:0,他引:2  
文中以内蒙古赤峰市敖汉旗大五家流域内防护林为研究对象,重点研究该流域内不同防护林涵养水源功能的现状,旨在评价不同植被类型水源涵养功能的差异,同时探寻低功能涵养水源型防护林更新改造途径。研究结果表明:不同防护林的土壤理化性质以及涵养水源功能差异明显,华北落叶松白榆混交、杨树柠条混交枯落物的现存量为3.4695~4.8536 t/hm2,最大持水量为64.225~66.125mm;华北落叶松白榆混交的植被类型具有良好的涵养水源能力,为164.563 t/hm2;灌木纯林和灌木混交林在实际调查中表现较差,在今后的森林经营中应考虑营造针阔混交林。  相似文献   
294.
Increasing urbanization of rural landscapes has created new challenges for wildlife management. In addition to changes in the physical landscape, urbanization has also produced changes in the socio-cultural landscape. The greater distancing from direct interaction with wildlife in urbanized societies has led to the emergence of a culture whose meanings for wildlife are less grounded in the utilitarian/instrumental orientation of rural agrarian systems. Urban perspectives on wildlife are comprised of more highly individualized emotional/symbolic values. This shift creates two problems with respect to managing wildlife in an urbanizing landscape. First the increased diversity in values and meanings increases the likelihood for social conflicts regarding wildlife management while at the same time making socially acceptable resolutions more intractable. This in turn requires fundamental changes in decision-making paradigms and the research approaches used to inform decision making. Second, as remaining rural communities feel the pressures of urbanization, wildlife conflicts become conflicts not just over wildlife but conflict over larger socio-political concepts such as equity, tradition, private property rights, government control, power, and acceptable forms of knowledge. This paper examines the wildlife management implications of changes associated with increasing urbanization and employs two case studies to illustrate these issues. First a study of a controversy over urban deer management provides insights into how to map conflicting values and search for common ground in an urban culture with increasingly individualistic values for wildlife. Specifically, the analysis illustrates that common ground may, at times, be found even among people with conflicting value systems. The second case study examined a ranching community faced with predator reintroduction. This case study illustrates tensions that occur when the community of interest (i.e. a national public) is broader than the community of place in which the problem occurs. In this latter situation, the debate centers around more than just different views about the rights of animals. It also entailed the rights of individuals and communities to decide their future. The conclusion discusses the need for wildlife institutions to adapt their underlying decision making philosophy including the way science is integrated into decision making processes in light of the changes in social context caused by urbanization.  相似文献   
295.
BACKGROUND: Integrated pest management (IPM) technology has been disseminated since 1989 in Indonesia to cut down pesticide use, but the adoption and diffusion of the technology are still debated. This study aims to estimate the models of demand for pesticides and to analyse the impact of IPM technology on pesticide use. Aggregate cross-section time series data from 1990-1998 are used.RESULTS: The results show that IPM technology reduces the use of pesticides by improving the process of rice production, such that pesticides are more efficiently used. In this case, the IPM technology is not a pest control technique.CONCLUSION There is an indication that IPM technology has been adopted by farmers. This is evidence that the IPM programme in Indonesia was successful in this area. Copyright (c) 2008 Society of Chemical Industry.  相似文献   
296.
电子商务的蓬勃发展给企业管理带来巨大冲击,财务管理作为企业管理链条上的重要一环,其管理模式也因此而发生了重大变革。文中首先介绍了网络财务管理产生的背景及其概念,讨论了网络财务管理的优势所在,明确了网络财务管理产生和发展的技术基础,重点对网络财务管理的开发与实施展开了探讨。  相似文献   
297.
目的研究海南热带地区典型植被类型土壤微生物群落结构特征,揭示植被特征和土壤理化特征对土壤微生物群落的影响。方法利用 BIOLOG-ECO 技术,对海南热带地区6种典型植被类型的土壤微生物功能多样性进行研究。结果不同植被类型土壤微生物的平均每孔颜色变化率(average well color development,AWCD)曲线基本一致,但碳源利用能力强弱有别。不同植被类型土壤192 h处的AWCD值大小顺序为:混交林>半红树林>次生林>椰子林>湿加松林>木麻黄林。不同林分类型对六大类主要的碳源利用率存在差异,混交林、半红树林、次生林和椰子林4种植被类型对碳水化合物、氨基酸类和多聚物的利用率最高,而木麻黄林和湿加松人工纯林土壤微生物对六大类碳源的利用率均不高,其中氨基酸类和羧酸类碳源是这2种人工纯林主要碳源利用形式。不同植被土壤微生物McIntosh指数、Shannon-Wiener指数、Simpson指数和Pielou指数也表现为混交林、半红树林和次生林高于人工纯林。主成分分析表明:不同植被类型土壤微生物群落代谢多样性能够明显区分,其中PC1可以解释所有变量方差的47.32%, PC2可以解释所有变量方差的31.58%,累计贡献达到78.90%。相关性分析表明:土壤微生物群落多样性各指标与土壤有机碳和全氮之间呈极显著正相关 (P<0.01),与土壤pH呈负相关,与土壤含水量呈显著正相关 (P<0.05)。结论相比纯林,人工混交林对于改善土壤微生物群落特征具有重要作用。  相似文献   
298.
紫肉火龙果为热带植物、亚热带植物,喜光耐阴、耐热耐旱。北方栽培要利用温室、塑料大棚等保护地生产。在栽培管理中利用水泥杆做支架,选向阳地段建园,栽培管理要薄肥勤施,及时浇水和排水,进行摘心、绑缚、修剪等植株管理,授粉、疏花疏果等花果管理,加强保护地温度、光照、空气湿度管理。  相似文献   
299.
壳斗科植物具有丰富花蜜和花粉.2007年4~7月,对云南哀牢山中山湿性常绿阔叶林壳斗科蜜源植物开发利用的潜力进行了初步研究.在该季节,中华蜜蜂可利用的壳斗科植物主要有木果石栎、景东石栎和腾冲栲.3种植物的花期均为50天左右.放置在原始森林林缘蜂群的取蜜量明显高于放置在原始森林内和附近次生林的蜂群.一群放置在林缘、群势为5标准框的中华蜜蜂蜂群,一个花期可以取蜂蜜约5 kg.  相似文献   
300.
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