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排序方式: 共有626条查询结果,搜索用时 46 毫秒
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1.双注射的标志方法双注射法是由两次单独的注射组成的,首先进行初级染色,然后进行次级染色。按前面所述的方法将初级染料的水溶液——固绿或台盼兰注射入实验对虾体内,次级染色物质用1或2ml结核菌素注射器25或27号针头注射。0.003~0.01ml的次级染色物质注射到中部背 相似文献
3.
1当前我国畜牧养殖标准化管理工作中存在的问题近年来,我国的畜牧养殖重点品种相继制订了无公害食品标准和相关的养殖技术规范,国家质检总局和农业部及各省、市(自治区)还相继出台了畜牧养殖标准化示范园区建设的有关奖励措施。验收通过了一大批国家级和省、市级的标准化示范园区,取得了一定的成绩。但是我国的畜牧养殖产品质量水平不高,总体形势不容乐观。种种迹象表明,我国畜牧养殖标准化推广实施工作中存在诸多问题,主要表现在:①重标准制订,轻标准宣传贯彻。各级政府行业主管部门比较重视畜牧养殖标准制订工作,但标准宣传培训面不广,宣… 相似文献
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各种工业与民用建筑物中,窗台抹灰或预制窗台,都要出现裂缝,裂缝大多从窗台中间出现。小窗台(长 1.5米左右)只从中间裂出一道横缝,大窗台(长 1.5—3米左右)除当中一道横缝之外,往往在两侧还陪衬两道小缝,这是建筑工程上的多发病。 分析窗台出现裂缝的根源,有设计方面的原因,也有施工方面的原因。 相似文献
5.
Danielsen EF 《Science (New York, N.Y.)》1981,211(4484):819-821
The plume of the major eruption of Mount St. Helens on 18 May 1980 penetrated 10 to 11 kilometers into the stratosphere, attaining heights of 22 to 23 kilometers. Wind shears rapidly converted the plume from an expanding vertical cone to a thin, slightly inclined lamina. The lamina was extruded zonally in the stratosphere as the lower part moved eastward at jet stream velocities, while the upper part slowly moved westward in the region of nonsteady transition from the westerlies to the summer stratospheric easterlies. Trajectories computed to position the NASA U-2 aircraft for sampling in the plume are described. Plume volume after 8 hours of strong volcanic emission is estimated at 2 x 10(6) cubic kilometers. Only about 1 percent of this volume is attributed to the volcano; the rest was entrained from the environment. 相似文献
6.
以温室夏黑葡萄为试材,研究了植物生长调节剂对夏黑葡萄果实品质的影响。结果表明:以盛花末期使用施特优300倍液保果,10d后用奇宝8 000倍液+施特优200倍液+链霉素200PPM进行蘸穗处理膨大效果较好,单粒重达8.43g,着色时期正常,可溶性固形物差异不大,在该地区整体表现较好。 相似文献
7.
Silva EF Brod CS Cerqueira GM Bourscheidt D Seyffert N Queiroz A Santos CS Ko AI Dellagostin OA 《Veterinary microbiology》2007,121(1-2):144-149
The main goal of this study was to obtain new isolates of Leptospira spp. from sheep. A total of 10 kidney samples and 44 blood samples were collected from sheep slaughtered in Pelotas, Southern Brazil. One isolate was obtained which was identified by 16S rRNA gene sequencing and serogrouping to be Leptospira noguchii serogroup Autumnalis. Microscopic agglutination test (MAT) evaluation revealed that 4.5% of the sheep sera reacted against the Autumnalis serogroup. This is the first report of isolation of L. noguchii from sheep. Together these findings indicate that L. noguchii infections may be a potentially important veterinary problem in this domestic animal species. 相似文献
8.
The California Milk Cell Test (CMCT) and somatic cell counts (SCC) on their own were not reliable methods in the identification of subclinical mastitis in the dairy goats studied and should be accompanied by microbiological tests. However, CMCT and SCC were indicators of irritation of the udder parenchyma. In healthy goats Spectrazol Milking Cow (Schering-Plough AH) caused the least and Curaclox LC (Norbrook (ARK AH)) the most irritation of parenchyma after intramammary treatment. The effects of Rilexine 200 LC (Logos Agvet (Virbac)) were intermediate. There was a highly significant difference (P < 0.001) in the mean log SCC between treated and control groups for goats treated with Curaclox LC and Rilexine 200 LC but no significant difference was present in the mean log SCC of treatment and control groups for goats treated with Spectrazol Milking Cow at the 07:00 and at 19:00 samplings. The CMCT was an indicator of the level of SCC in goat milk. The CMCT was more useful in confirming the absence of infection, rather than in diagnosing mastitis. 相似文献
9.
我国的竹叶兰花很少应用在观赏领域,多用于解毒药的制作,并且受过度开采影响,野生竹叶兰花的数量越来越少,已经被列为国家二级保护植物。深入研究竹叶兰花,分析其开花习性和发育特性,能够为其在园林观赏等方面的应用奠定基础,实现经济效益最大化。因此,对竹叶兰花的器官发育特征和生理特性进行分析研究,能够更好地掌握其生长发育状况和生长习性,有利于竹叶兰花的栽培管理,同时对于新花卉作物的开发具有一定帮助。文章在收集资料、查找文献以及观看他人试验数据的基础上展开分析,分析了竹叶兰花器官发育特征以及生理特性,以供参考。 相似文献
10.
Sirk TW Brown EF Sum AK Friedman M 《Journal of agricultural and food chemistry》2008,56(17):7750-7758
Molecular dynamics simulations were performed to study the interactions of bioactive catechins (flavonoids) commonly found in green tea with lipid bilayers, as a model for cell membranes. Previously, multiple experimental studies rationalized catechin's anticarcinogenic, antibacterial, and other beneficial effects in terms of physicochemical molecular interactions with the cell membranes. To contribute toward understanding the molecular role of catechins on the structure of cell membranes, we present simulation results for seven green tea catechins in lipid bilayer systems representative of HepG2 cancer cells. Our simulations show that the seven tea catechins evaluated have a strong affinity for the lipid bilayer via hydrogen bonding to the bilayer surface, with some of the smaller catechins able to penetrate underneath the surface. Epigallocatechin-gallate (EGCG) showed the strongest interaction with the lipid bilayer based on the number of hydrogen bonds formed with lipid headgroups. The simulations also provide insight into the functional characteristics of the catechins that distinguish them as effective compounds to potentially alter the lipid bilayer properties. The results on the hydrogen-bonding effects, described here for the first time, may contribute to a better understanding of proposed multiple molecular mechanisms of the action of catechins in microorganisms, cancer cells, and tissues. 相似文献