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1.
研究了国产替米考星注射用药对人工感染多杀性巴氏杆菌病猪的治疗效果,用断奶仔猪进行试验,为临床使用提供了依据.结果表明,替米考星治疗急性猪肺疫效果确实, 推荐剂量为10 mg/kg体重.  相似文献   
2.
AIM: To investigate expression of CD44s in lung cancer and it's clinical significance. METHODS: A total of 117 primary lung cancer from patients were examined for CD44s expression by immunohistochemical staining. RESULTS: CD44s mostly expressed in non-small cell lung cancer (NSCLC) but not in small ecll lung cancer (SCLC), and squamous cell carcinoma(SCC) showed much stronger expression of CD44s than adenocarcinoma(ADC)(P<0.05). In comparison of the lung cancer with/ without lymph node metastasis, the latter showed stronger expression of CD44s(P<0.01). According to TNM, there was a distinct statistic difference between early stage and advanced stage(P<0.05). CONCLUSION: CD44s might be a better indicant in histological classification of lung cancer, lymph node metastasis, clinical stage and prognosis.  相似文献   
3.
利用2000倍液、3000倍液、4000倍液3个不同体积分数的3%高渗苯氧威进行了室内、室外防治春尺蠖幼虫试验,结果表明:施药72h后,室内试验的3个体积分数平均死亡率均达到100.0%;室外试验以2000倍液和3000倍液死亡率为最高,达到98.5%,防治效果显著。3%高渗苯氧威是理想的防治春尺蠖的仿生物杀虫剂。  相似文献   
4.
Forage brassicas are widely used as a supplementary feed in temperate pasture systems but there is a lack of quantitative data about their growth and development. Furthermore, numerous models are available to estimate cardinal temperatures but there is uncertainty about whether linear or nonlinear models should be used. Initially a germination experiment was used to describe the rate response of nine forage brassicas to temperature. Three models were compared to estimate cardinal temperatures and the two best models were used for thermal time (Tt) accumulation for three groups of forage brassicas. Cardinal temperatures, defined as the base (Tb), optimum (Topt) and maximum (Tm), differed among groups of species for the bilinear and Lactin models but were similar within a group of species for these models. In most cases, cardinal temperatures estimated by the bilinear and Lactin models for the B. rapa group ranged from 3 to 4 °C for Tb, 31 °C for Topt and 41 to 48 °C for Tm. For the B. napus and B. napus biennis groups these temperatures ranged from 0 to 3 °C for Tb, 29 to 33 °C for Topt and 38 °C for Tm. The B. oleracea group had temperatures from 0 to 1 °C for Tb, 25 to 27 °C for Topt and 35 °C for Tm. A second data set based on hypocotyl thickening was used to estimate the base temperature (Tb) for bulb growth of turnips and swedes. Both models estimated an average Tb of 4.2 °C for bulb turnips and an average of 3.7 °C for swedes. The Lactin model was considered the most adequate model to describe temperature responses where as, in some cases, the bilinear model had to be modified to account for changes in the rate of development. More importantly, an appropriate range of test temperatures was crucial for the estimation of reliable cardinal temperatures, independent of the model used.  相似文献   
5.
为了探索45%丙环唑悬浮剂对青海省春小麦的安全性,设置45%丙环唑悬0.2、0.4、0.8 mg·g-1的不同处理。结果表明以株高和鲜重抑制率为指标,各品种对药剂的敏感性差异显著;在0.2 mg·g-1剂量下青春38、青春39、通麦1号、阿勃4个品种安全;在丙环唑0.4 mg·g-1剂量下对青春38、青春39、阿勃安全,对通麦1号安全性差;在丙环唑0.8 mg·g-1剂量下对4个品种的安全性都较差。  相似文献   
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7.
介绍了搅拌机最基本的设计步骤,首先确定了执行机构的运动机构,确定四杆机的长度,验证是否合适;验证曲柄存在的条件,检查连杆是否干涉,验证四杆机构的传力性能以验证四杆机构是否有较高效率;计算出溶液阻力从而列出力矩平衡方程求出平衡力,求出阻力矩,利用阻力矩与等效驱动力矩之间的关求出最大盈亏功,从而确定飞轮惯量;最后确定了电动机的功率。  相似文献   
8.
为探究辣椒单株结果数的遗传机制,以单株结果数差异较大的辣椒材料XHB(P1)和B14-01(P2)为亲本,构建四世代遗传家系即P1、P2、F1、F2。运用主基因+多基因多世代联合分析法,研究辣椒单株结果数的遗传规律。结果表明:辣椒单株结果数符合2对加性-显性-上位性主基因模型(2MG-ADI)。2对主基因的加性效应值da、db分别为-16.33、-13.05,2对主基因的显性效应值ha、hb分别为-10.02、-2.51。2对主基因间的加性×显性(jab)互作效应和显性×加性(jba)互作效应的效应值分别为8.69和12.93,加性×加性上位性(i)互作效应值为6.86,显性×显性(l)的互作效应值为7.23,主基因间的效应以加性效应为主,其次是加性×显性上位性互作效应。主基因遗传率为68.10%,环境引起的变异占比31.9%...  相似文献   
9.
建立了10%世高水分散剂在白菜及土壤中的残留分析方法。该方法的最小检出量为1.2×10-12g。以0.0100 mg/L,0.1000 mg/L,1.000 mg/L进行添加回收试验,结果表明,白菜植株的平均回收率为90.7%~92.8%,相对标准偏差为1.2%~8.5%;土壤样本的回收率为87.2%~92.9%,相对标准偏差为2.5%~9.1%。该方法的灵敏度、准确度、精密度均符合农药残留技术测定要求。  相似文献   
10.
Climatic changes and elevated atmospheric CO2 concentrations will affect crop growth and production in the near future. Rising CO2 concentration is a novel environmental aspect that should be considered when projections for future agricultural productivity are made. In addition to a reducing effect on stomatal conductance and crop transpiration, elevated CO2 concentration can stimulate crop production. The magnitude of this stimulatory effect (‘CO2 fertilization’) is subject of discussion. In this study, different calculation procedures of the generic crop model AquaCrop based on a foregoing theoretical framework and a meta-analysis of field responses, respectively, were evaluated against experimental data of free air CO2 enrichment (FACE) environments. A flexible response of the water productivity parameter of the model to CO2 concentration was introduced as the best option to consider crop sink strength and responsiveness to CO2. By varying the response factor, differences in crop sink capacity and trends in breeding and management, which alter crop responsiveness, can be addressed. Projections of maize (Zea mays L.) and potato (Solanum tuberosum L.) production reflecting the differences in responsiveness were simulated for future time horizons when elevated CO2 concentrations and climatic changes are expected. Variation in future yield potential associated with sink strength could be as high as 27% of the total production. Thus, taking into account crop sink strength and variation in responsiveness is equally relevant to considering climatic changes and elevated CO2 concentration when assessing future crop production. Indicative values representing the crop responsiveness to elevated CO2 concentration were proposed for all crops currently available in the database of AquaCrop as a first step in reducing part of the uncertainty involved in modeling future agricultural production.  相似文献   
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