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Prosperity and Disappearance of Introduced Fishes in Xiangmoshan Reservoir
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作者 FAN Zhaoting CHEN Weixing LIU Yi FANG Jingjie LIU Qingzhen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第3期29-37,共9页
In order to enhance the resources, some fishes were introduced into Xiangmoshan reservoir. The introduced fishes consisted of different ecotypes such as silver carp (Hypophthahnichthys rnolitrix (Cuvier et Valencien... In order to enhance the resources, some fishes were introduced into Xiangmoshan reservoir. The introduced fishes consisted of different ecotypes such as silver carp (Hypophthahnichthys rnolitrix (Cuvier et Valenciennes)), big head (Aristichthys nobilis (Richardso)) and lake herring (Coregonus clupeaformis (Mitchill)) that were plankton feeders, common carp (Cyprinus carpio Linnaeus) and crucian carp (Carassius auratus gibelio) belonging to the polyphagia, and also the non-native predator Walleye (Stizostedion vitreum (Mitchill)) and big mouth (Silurus soldatovi rneridonalis Chen), et al. Among there were not only the cool water fish Peled (Coregonus peled (Gmelin)), but also the warm water fish big mouth. The introduction of non-native fishes resulted in ecosystem changes of the reservoir and some native fishes had gone to decrease their population sizes or been in the condition of depopulation such as Opsariichthys uncirostris arnurensis (Berg), Rhodeus sericeus (Pallas) and Silurus asotus (Linnaeus). The native common carp had disappeared after the introduction of non-native species. Roach (Rutilus rutilus lacustris (Pallas) had been thriven for one or two generations after its introduction and immeidiatly disappeared. Silver fish (Protosalanx hyalocranius (Abbott)), Lake herring (Coregonus clupeaformis (Mitchill)) and Walleye (Stizostedion vitreum (Mitchill)) died several years after the introduction, so most of the introduced species has passed out of existence. Via many years introduction of different fishes, composition of species and the structure of the population in the reservoir had been changed obviously. It was necessary to further estimate whether the ecosystem of the reservoir had been damaged. 展开更多
关键词 Xiangmoshan reservoir introdued fish prosperity and disappearance ecological damage
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略论海上丝绸之路引种的几个有争议问题 被引量:7
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作者 刘明金 《湛江海洋大学学报》 CAS 2005年第5期21-23,共3页
陆海两条丝绸之路的开辟,至今已有2100多年的历史。由陆海两条丝绸之路引进的植物种苗不计其数。针对芒果、木菠萝、菩提树、椰子等几种有争议的植物引种问题进行探讨。
关键词 丝绸之路 国计民生 植物引种
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Biochemical Mechanism of the Eutrophication and Its Prevention — the Deep Treatment of Waste Water and Its Denitrification and Dephosphorization
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作者 李红山 黎松强 《Marine Science Bulletin》 CAS 2003年第1期32-39,共8页
Biochemical mechanism of forming the red tide is discussed in this paper. The existence of a large number of nitrates and phosphates in the eutrophic water is the prerequisite of explosive increase of algae and the fo... Biochemical mechanism of forming the red tide is discussed in this paper. The existence of a large number of nitrates and phosphates in the eutrophic water is the prerequisite of explosive increase of algae and the forming of red tide. Reduction of eutrophication is an important approach to preventing the red tide. The method of deep treatment of the waste water and its denitrification and dephosphorization are introduced, and a new opinion on the red tide formation and fundamental prevention is put forward. 展开更多
关键词 red tide EUTROPHICATION biochemical mechanism prevention1 introdu
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我国国家级贫困县的人才现状和引进模式研究
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作者 赵静 《价值工程》 2007年第12期18-20,共3页
如何科学有效地引进人才资源,这是长期以来困扰国家级贫困县的突出问题。通过分析国家级贫困县的人才资源现状,揭示了引进人才是解决人才紧缺问题的有力措施;并具体阐述了引进人才的四种模式。基于对引进人才模式的深入研究,以期为国家... 如何科学有效地引进人才资源,这是长期以来困扰国家级贫困县的突出问题。通过分析国家级贫困县的人才资源现状,揭示了引进人才是解决人才紧缺问题的有力措施;并具体阐述了引进人才的四种模式。基于对引进人才模式的深入研究,以期为国家级贫困县的人才开发提供依据。 展开更多
关键词 国家级贫困县 人才资源 引进模式
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平菇原生质体电击导入荧光标记物质研究初报 被引量:2
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作者 周金树 姚乌兰 +1 位作者 刘淑卿 刘化民 《食用菌学报》 1994年第1期50-52,共3页
本研究探索采用电击法导入荧光标记物的条件。发现钙黄素荧光标记物可以导入平菇原生质体,脉冲强度在0~1500v/cm条件下,导入率呈线性增长,成活率则下降,两种观测指标呈相反趋势。平菇原生质体的最适电击脉冲强度为1500v/cm(3×1.1... 本研究探索采用电击法导入荧光标记物的条件。发现钙黄素荧光标记物可以导入平菇原生质体,脉冲强度在0~1500v/cm条件下,导入率呈线性增长,成活率则下降,两种观测指标呈相反趋势。平菇原生质体的最适电击脉冲强度为1500v/cm(3×1.1cm)。 展开更多
关键词 平菇 原生质体 电击导入 钙黄素
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Falx Meningeoma Induced Optic Neuropathy-Clinical Manifestation and Differential Diagnosis:A Case Report
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作者 Skevas Christos Gorsch Isabel Carolin +1 位作者 Richard Gisbert Linke Johannes Stephan 《Open Journal of Ophthalmology》 2013年第3期87-89,共3页
Purpose: Meningiomas are the most frequently diagnosed neoplasms. Ocular symptoms vary depending on size and localisation of the tumor, which is capable of compressing critical anatomic structures. Patients and Method... Purpose: Meningiomas are the most frequently diagnosed neoplasms. Ocular symptoms vary depending on size and localisation of the tumor, which is capable of compressing critical anatomic structures. Patients and Methods: A 44-year-old immunocompetent male was admitted to our hospital for further investigation of his bilateral optic disc swelling. A complete ophthalmological examination was performed including visual field assessment (VF), visual evoked potentials (VEP), fluorescein angiography (FLA) and magnetic resonance imaging (MRI). The patient had experienced only minor visual disturbances. Serological testing was performed. Results: Serological testing showed positive IgM and IgGtiters for cytomegalovirus (CMV) and subsequent imaging (MRI) revealed a frontal falxcerebri meningioma. Conclusions: We present a case of falx meningioma with overlapping serologically active CMV in an otherwise healthy and immunocompetent individual. Detailed differential diagnostic workup in immunocompetent individuals presenting with clinically unremarkable bilateral disc swelling is recommended. 展开更多
关键词 Falx Meningeoma Optic Neuropathy Cytomegalovirus(CMV) Visual Disturbances Fluorescein Angiography(FLA) Magnetic Resonance Imaging(MRI) Visual Evoked Potentials(VEP)1.introdu
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刚察县22种多年生禾草引种试验报告 被引量:16
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作者 黎明 王梅花 《青海畜牧兽医杂志》 2002年第3期8-9,共2页
1999— 2 0 0 1年对 2 2种国内外牧草及野生驯化牧草的物候期进行了田间观察 ,通过牧草的越冬率、鲜草产量、种子产量、千粒重等综合因素进行分析 。
关键词 刚察县 多年生禾草 引种试验 物候期
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高校学生德育工作与社工方法的结合
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作者 张姝 《化工高等教育》 2012年第5期104-108,共5页
高校学生德育工作一直受到社会各界的广泛关注,但是德育的效果却并不令人满意。本文通过对社会工作方法的简单介绍,对目前高校德育工作中存在的问题进行分析,并尝试将社会工作的小组工作方法引入高校的学生德育工作之中,以期能为高校学... 高校学生德育工作一直受到社会各界的广泛关注,但是德育的效果却并不令人满意。本文通过对社会工作方法的简单介绍,对目前高校德育工作中存在的问题进行分析,并尝试将社会工作的小组工作方法引入高校的学生德育工作之中,以期能为高校学生德育提供一种新的方式,帮助提高高校学生的德育工作效果。 展开更多
关键词 社会工作 小组工作 高校学生德育 小组工作方法引入方式
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沿江高铁引入扬州地区方案研究 被引量:4
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作者 刘国林 《铁道建筑技术》 2019年第1期114-117,共4页
沿江高铁是高速铁路网中沿江通道的重要组成部分。扬州作为沿江高铁必经节点,地区目前既有铁路有宁启铁路,已开工建设铁路有连镇铁路,规划、拟建铁路有扬马城际铁路、沿江高铁,规划沿江高铁也提上建设日程,届时扬州将成为衔接南京、淮... 沿江高铁是高速铁路网中沿江通道的重要组成部分。扬州作为沿江高铁必经节点,地区目前既有铁路有宁启铁路,已开工建设铁路有连镇铁路,规划、拟建铁路有扬马城际铁路、沿江高铁,规划沿江高铁也提上建设日程,届时扬州将成为衔接南京、淮安、上海、镇江等多个方向的关键地区。沿江高铁引入不仅要解决地区存在的问题,还要考虑规划预留发展。通过对扬州地区铁路现状进行分析,统筹考虑该地区在建项目和规划项目,对地区引入方案进行系统研究,从多方面进行分析比较,提出沿江高铁引入扬州地区的最佳方案,以完善地区总图。引入扬州地区方案具有代表性,通过沿江高铁引入扬州地区方案研究,可总结出高速铁路引入扬州这样节点的规律和方法。 展开更多
关键词 引入方案 系统研究 方案对比
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