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在湖南省按照不同地貌类型和地类破碎程度抽取4 km×4 km大样地10个,采用不同判读方式(充分参考林业档案信息与不参考林业档案信息)和不同判读人员(有5年以上遥感判读经验人员与无任何遥感判读经验人员)对10个大样地进行遥感判读区划,并对判读区划结果进行实地调查验证。分析表明:各地类正判率与其面积成正相关,其它调查因子判读难度较大;充分参考林业档案信息能够显著提高正判率,但优势树种、起源、龄组、郁闭度等因子综合正判率仍然偏低;不同判读工作经验人员对遥感判读有一定的影响,无判读工作经验人员应经过一定程度培训后才可参与判读工作。 相似文献
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概述了早竹学名变动的历史沿革,支持将Phyllostachys violascens(Carr.) A.et C.Riv.作为早竹的正确学名,而将Ph.praecox C.D.Chu et C.S.Chao减为其异名的分类学处理结果。通过文献考证和实物照片比较分析认为,在国产早竹复合体中,产于浙皖毗连地区的新秆深绿带紫色、密被白粉、节部紫色,老秆灰绿色或黄绿色并有暗黄色或淡褐色纵条纹,其土名称之为"土早竹"(也称"宽叶早竹")这一类型与Ph.violascens(Carr.) A.et C.Riv原植物相符。而Ph.praecox C.D.Chu et C.s.Chao模式植株则为栽培品种"余杭早竹",但其原发表时的营养器官形态描述中混有"土早竹"的特征。随着近20余年来"土早竹"资源的锐减,应加强其保护。 相似文献
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Objectives
To review the methods for verifying the needle position while performing epidural anaesthesia in dogs, and to discuss the advantages, disadvantages, usefulness and reliability of each technique in the experimental and clinical research setting.Databases used
PubMed, Scopus, Google Scholar and the Basel University Library online catalogues; the latter, which was provided by the University of Berne, were used as databases. The results were filtered manually based on the titles and abstracts in order to narrow the field.Conclusions
Besides some drawbacks, including the potential side effects of contrast medium injection, which may limit its routine use in clinical patients, epidurography should still be regarded as one of the most reliable techniques to verify needle position in dogs. Ultrasonography, electrical nerve stimulation, loss of resistance and the hanging drop technique are regarded as less invasive than epidurography and, for this reason, their use may be more applicable to clinical patients. However, these methods have been described in only a few published reports, all of which involved a limited number of dogs. Finally, the detection of epidural pressure waves has been investigated more extensively in dogs, and the findings of these studies suggest that this technique may be used to verify epidural needle placement for experimental and clinical research, on condition that all the negative subjects are excluded from the study. 相似文献7.
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先天性膝盖骨内侧或外侧脱位是年轻动物的膝盖骨从滑车沟向内或外侧脱位.膝盖骨脱位程度不同,最轻的呈现膝盖骨从滑车沟偶而滑出,最重的呈现膝盖骨从滑车沟完全或永久脱位.在德国柏林自由大学宠物临床门诊,共接诊不同品种、年龄、性别的32例病犬.对64个膝盖骨通过X线和内窥镜检查,测量出膝关节的不同脱位方向,滑车沟的深度及两侧嵴的厚度值,并将其与关节正常值比较,得知脱位原因是膝关节先天性发育不全所致.脱位有单膝内外脱及双膝内外脱等不同程度方向的脱位,造成病犬高度跛行、行走困难、疼痛等症状.对犬的正常生活和活动产生了极大的影响.在临床上对不同程度的脱位进行了外科手术调整而达到了满意的效果. 相似文献
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近几年,国际油价居高不下,使农业生产的成本增加,因此,合理选用动力机械,正确操作和使用、及日常维护显得尤为重要,所以,文章进一步提出加强农机队伍建设和农机具的管理也是必不可缺少的。 相似文献
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Outdoor Acceletated Weathering Equipment is the most widely used outdoor acceletated weathering test method in the world today. The success in development of this equipment will have a far-reaching and promoted effect on R&D of new material and new dope. Automatic and all-weather tracing solar is the tackle key problem. A new method of tracking the sun is presented, and the sun track is corrected with this method. The operation principle of a solar-tracking sensor is introduced. 相似文献