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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
C肉毒杀鼠素在高寒草甸地区灭鼠技术的应用 总被引:1,自引:0,他引:1
综述C肉毒杀鼠素草原灭鼠应用技术,充分肯定了C肉毒杀鼠素毒力强、适口性好、对非靶动物毒性低、作用缓慢、无二次中毒、易降解和适合规模灭鼠的特点,为鼠害防治提供了新的思路。 相似文献
962.
Turlough F. Guerin 《Journal of Soils and Sediments》2001,1(3):133-136
Internet listservers, a freely available resource on the Internet for anyone who can send and receive emails, provide a means
for professionals to communicate and collaborate with each other in the field of soils and sediments. While moderated listservers
are highly effective, in terms of quality and participation (activity) level, do not underestimate the knowledge base held
within many of the soil and sediment-related listservers. Readers are encouraged to subscribe to those lists which match their
own areas of the soil and sediment fields and to become active. Currently, the only listservers dedicated to sediments are
of very low activity, with the lowest numbers of subscribers of all listservers surveyed. As a word of caution, Internet listservers
are not a primary source of knowledge (in any scientific field), the quality of knowledge exchanged is highly variable, and
if not properly managed, can waste time. 相似文献
963.
犬冠状病毒的分离鉴定及其纤突蛋白基因的克隆与序列比较 总被引:10,自引:0,他引:10
以犬胎原代细胞,采用同步接种、带毒传代和添加新细胞的方法,从1例腹泻犬脾脏和1例临床健康犬肠内容物中分离出2株犬冠状病毒(CCVYS1,CCV CI1)。该2株病毒可使CRFK细胞出现典型的细胞融合病变,与从美国引进的CCVNL-18参考株形成的细胞病变相似;电镜负染和超薄切片观察,分离毒株细胞培养物中均含有典型的冠状病毒粒子,并形成胞浆内包涵体;经理化学、生物学鉴定,濉有CCV的特性;间接免疫荧 相似文献
964.
965.
966.
967.
A. Flåøyen H. Hjorth Tønnesen H. Grønstøl J. Karlsen 《Veterinary research communications》1991,15(6):483-487
It has been suggested that saponins produced by Narthecium ossifragum (Bog asphodel) may be the direct cause of the toxicity leading to the hepatogenous photosensitivity disease alveld seen in Norwegian lambs. Lambs fed large quantities of freeze-dried N. ossifragum did not develop alveld. Chemical investigations on the freeze-dried material and fresh N. ossifragum showed no difference in their saponin content. These results indicate that alveld is not caused solely by the saponins produced by N. ossifragum. 相似文献
968.
阳东辉 《湖南农业大学学报(自然科学版)》2001,(3)
鉴于我国公司法对公司相互持股问题的规制处于空白之现状,文章借鉴国际上最新立法成果,分析了公司相互持股所引发的诸多问题,并提出规制公司相互持股问题的建议与构想。 相似文献
969.
I. Kisic F. Basic O. Nestroy M. Mesic A. Butorac 《Journal of Agronomy and Crop Science》2002,188(5):323-334
In a 5‐year stationary investigation at an experimental station in central Croatia, total amounts of erosional drift were measured on a Stagnic Luvisol on which six tillage methods were used. The chemical properties of the tilled soil and the erosional drift were recorded for each trial method in the same plots. A generally higher soil reaction value, higher organic matter content and larger amounts of available phosphorus and potassium were found in the majority of erosional drifts compared to plot soil. On black fallow, erosional drifts contained significantly larger amounts of organic matter, available phosphorus and potassium than in other treatments. Higher contents of organic matter, phosphorus and potassium were recorded in erosional drifts from spring crop cultivation than in those from cultivation of winter wheat, oil‐seed rape and a consociation of summer barley and soybean. Also, higher losses of organic matter, phosphorus and potassium by erosional drift were recorded for the up/down the slope tillage methods than for no‐tillage and tillage across the slope. This suggests that no‐tillage and tillage across the slope can be recommended for this region, since these tillage methods conserve the soil and substantially reduce water pollution by chemical agents applied in agricultural production. 相似文献
970.
在介绍区域网络化生产及其特征的基础上 ,对中小企业组织创新进行了深入探究。指出了动态联盟是网络化生产背景下中小企业间集成的组织原则 ,网络治理是替代科层治理的有效形式 ,员工观念和企业文化是影响企业创新的重要因素 ,从而得出了要成功实施区域网络化生产 ,除应重视硬件技术的建设外 ,还应重视软件要素的营造的结论。 相似文献