Habitat use of an artificial wetland by the invasive catfish Ameiurus melas   总被引：1，自引：0，他引：1  

J. Cucherousset  J.-M. Paillisson  A. Carpentier  M.-C. Eybert  J. D. Olden 《Ecology of Freshwater Fish》2006,15(4):589-596

Abstract –  This study examined the distribution and habitat selection of the invasive black bullhead [ Ameiurus melas (Rafinesque)] in the ditches and surrounded temporary flooded habitats of an artificial wetland in western France. A multiscale approach was used to quantify patterns of A. melas abundance in relation to physical habitat characteristics in the ditch network. Young-of-the-year (YOY) and adult A. melas largely dominated the local fish assemblage but were highly variable among sites. Although we found evidence for some fine-scale habitat differences for YOY and adult individuals, the abundance of A. melas was positively and consistently related to the dominance of reed beds. Furthermore, A. melas preferentially used reed beds as opposed to marsh meadows during the flooding period. The results from this study suggest that the invasion of A. melas has been facilitated by the expansion of reed beds associated with the diminution of agricultural pressure in recent decades. This study represents an unusual example where human activities can have had an unexpected effect by facilitating an invasive fish species.  相似文献   

中国流行株HIV及其与细胞因子基因共表达核酸疫苗质粒的构建及表达     

郭焱  郭巍  顾红缨  李璐  于伟光  刘斌  罗晶 《动物医学进展》2003,24(1):78-80

以表达中国流行株HIV-1gp120基因的核酸疫苗质粒pGP及共表达中国流行株HIV-1gp120基因与IFN基因的核酸疫苗质粒pG-PIFN转染BHK-21细胞,以间接免疫荧光鉴定其表达产物。将上述两种质粒经胫前肌注射BALB/c鼠,检测gp120抗体的产生情况及ConA和Lps诱导的T细胞增殖能力。结果显示,荧光显微镜下pGPIFN转染细胞可见绿色荧光而pGP转染细胞未见绿色荧光。pGPIFN与pGP均可刺激小鼠产生抗gp120抗体,协同注射gp120和IFN基因的小鼠产生的抗体滴度明显高于单独注射gp120的小鼠。pGPIFN免疫鼠对ConA和Lps诱导的T细胞增殖能力明显高于单独注射gp120的小鼠。实验结果表明,协同应用IFN基因可明显加强HIV-1gp120基收稿日期:2002-07-19基金项目:国家自然科学基金项目(3977066);国家杰出青年基金项目(39825119)作者简介:郭　焱(1963-),女,吉林省长春市人,长春中医学院基础医学部副教授,硕士,主要从事分子病毒学研究工作。因的免疫反应,为中国流行株HIV-1核酸疫苗的可行性提供了重要实验依据。  相似文献   

开发建设项目水土保持方案的探讨   总被引：2，自引：0，他引：2  

陈家才  王和平 《中国水土保持》1997,(1):39-41

<正> 1 开发建设中水土保持问题的提出水土保持工作不仅关系到社会和经济的发展、人民脱贫致富和生态环境的改善,而且也关系到江河湖泊的开发治理和国家能源、铁路、交通、工矿等方面的建设.开展水土保持工作,意义重大.  相似文献   

Anatomical and physiological characteristics of ostrich (Struthio camelus var. domesticus) meat determine its nutritional importance for man     

Ross Gordon COOPER  Jaroslaw Olav HORBAÑCZUK 《Animal Science Journal》2002,73(3):167-173

The ostrich is increasingly gaining interest as a livestock animal because of its potential to produce healthy red meat with a low fat content. This article describes the characteristics of ostrich meat that allow it to be marketed as a healthy alternative to beef. The muscles utilized for human consumption include the dorsal Muscularis obturatorius medialis and the hindquarters. The trade names of ostrich muscles are currently not standardized and classification is based on location and scientific nomenclature. Meat cuts of a high commercial value reach as much as 80–90% in the ostrich compared with approximately 45% in other species. Described here are key product characteristics important in its marketing, including fat content, cholesterol, fatty acids, sodium, iron, color, flavor and odor, tenderness, pH and water-holding capacity.  相似文献   

Effects of two EBV-LMP1 variants on proliferation characteristics of CNE1 cell line     

HUANG He  HUANG Pei-chun  ZHANG Su-zhen  CHEN Jin 《园艺学报》2004,20(10):1890-1894

AIM: To investigate the possible effect of different Latent membrane protein 1 (LMP1) variants on proliferation characteristics of a human well-differentiated nasopharyngeal carcinoma (NPC) cell line CNE1. METHODS: The plasmids which carried EBV-LMP1 gene cloned from B95-8 lymphocyte (B95-8-LMP1) and NPC tissues (CAO-LMP1) were introduced into CNE1 by liposomal transfection. Expression of LMP1 in CNE1 was identified by RT-PCR and Western blot, respectively. Different Effects of the two EBV-LMP1 variants on proliferation characteristics of CNE1 including growth curve, cell cycle distribution and clony-forming efficiency were investigated by means of crystal violet staining proliferation assay, flow cytometry and plastic plate clony-forming assay, respectively. RESULTS: Two transfected cell lines stably expressing different LMP1 variants were established successfully. Either of the two LMP1 variants increased CNE1 growth rate, proliferation index (PI) and clony-forming rate significantly and CAO-LMP1 had more significant growth-promoting effect on CNE1 than B95-8-LMP1. CONCLUSION: It can be concluded from the study that CAO-LMP1 promotes CNE1 proliferation more effectively than B95-8-LMP1.  相似文献   

论生态危机的四种根源及其特征     

彭福扬  曾广波 《湖南农业大学学报(自然科学版)》2002,(4)

生态危机的根源众多,归纳起来,主要有四种,即市场根源、认识根源、科技根源和政治根源.主要从市场的成本分摊性、人类中心论、科技异化以及政治对致毁性技术应用的加速作用分别对上述四种根源及特征进行了深入分析.  相似文献   

Status Quo and Expectation of Human-machine Interaction in HCR     

LI Gang  HUANG Xi yue  YUAN Rong di  HUANG Tong yuan 《保鲜与加工》2003,(5):59-63

Human-centered idea and human-machine collaboration are emphasized in the Human Centered Robotics, which is mainly used for human-machine cooperation required mission in dynamic and non-structural environment. This paper presents a WearComp based interface that gets over the space and time limitation on human-robot interaction. By adapting AR(augment reality) in outputting channel, the information of robotics status and warning was accentuated in the transmission. That method effectively saves the resources of transmission band and reappearance, lightens the burden of operators and contributes to a good operator consciousness to local condition and remote environment. By parallel and mutual compensation of MultiModality interaction, and by integrating and fusing the redundant information, the ambiguity and noise of inputting information can be eliminated. All of above get rid of input bottleneck; a more efficient and humanistic human machine interaction is provided.  相似文献   

人地关系协调发展初探     

刘敏  赵春秀 《山西农业大学学报(自然科学版)》1997,17(4):356-359

本文通过对人类历史与自然地理环境的相互作用，相互影响，以及人地矛盾种种表现的阐述，提出人地关系协调论的重要性及协调人地关系中应遵循的规律。  相似文献   

兔、猫和人的腓肠肌外侧头肌亚体与肌纤维型比较研究   总被引：2，自引：0，他引：2  

朱道立  王康乐  朱新宇 《动物医学进展》2002,23(4):91-96

目的是探讨兔、猫与人的腓肠肌外侧头肌亚体与肌纤维型的分布。采用人体解剖结合组织化学方法确定其肌亚体，并作肌动球朊ATP酶酸碱法染色，毛细血管数量统计及其三型肌纤维的直径与面积的图象分析。结果表明，兔、猫与人各肌亚体FG型纤维数比例为最高，FOG型纤维居中，SO型肌纤维最少。各肌亚体SO型纤维毛细血管数目最多，家兔、猫与人均为为内侧亚体的毛细血管／mm^2数目为最多。各肌亚体SO型纤维直径与面积为最小。说明人与哺乳动物各肌亚体均见有包裹纤维和快缩纤维的同型聚集。  相似文献   

新农村建设中的人力资源问题     

李燕 《信阳农业高等专科学校学报》2007,17(4):76-78

目前,我国农村的人力资源无论在数量上还是在质量上都难以满足新农村建设的要求。政府应制定切实可行的政策保证农村人力资源的数量和质量;应通过基础教育、职业教育和成人教育,完善医疗和社会保障制度等途径提高农村人力资源的质量。开发农村人力资源应借鉴国外成功经验。  相似文献