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11.
在小蚕片叶立体一日一回育的基础上,试验了平行串法小蚕片叶立体一日一回育,与立体一日二回育比,节约用桑3%,节约劳力36%,张种产量提高8.5%,还阐明了该法的技术要点。 相似文献
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A modified one-stage surgical repair was performed on eight mares that suffered from third-degree rectovestibular lacerations. The rectovestibular septum was reconstructed by three lines of sutures using polydioxanone. Primary healing was achieved in seven mares. Four mares got pregnant after the surgery, and no further injury was noticed at subsequent delivery. Complications of the currently used technique included pneumorectum (in one mare) and rectovestibular fistula (in another mare). The obtained results indicated that mares with third-degree rectovestibular lacerations are candidates for this modified one-stage technique with satisfactory outcome for subsequent fertility. 相似文献
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The purpose of this study was to evaluate the threshold of Toxocara canis eggs form soil samples through utilisation of a centrifuge-flotation technique (CFT). Aliquots of soil (1 g each) were artificially contaminated with known numbers of T. canis eggs (1, 10, 25, 50, 100, and 200 eggs). The threshold was evaluated based on a CFT using zinc sulphate (Zn2SO4) and sodium nitrate (Na2NO3) solutions at a specific gravity of 1.20. The number of eggs recovered was directly proportional to the number of eggs employed to seed the soil. Both solutions enabled full recovery of samples containing merely three eggs; only Zn2SO4 demonstrated efficiency in soil contaminated with a single egg. A recovery rate of 100% was obtained for all tests with samples containing 10 and 25 eggs for Zn2SO4 and Na2NO3, respectively. There was no difference in the mean number of recovered eggs regarding either the efficacy of the solutions or the repetition of evaluations in the same trial (p > 0.05). Therefore, the CFT is efficient for the detection of Toxocara eggs, even in samples containing low egg numbers. 相似文献
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应用单引物PCR指纹技术分析Vc-獭兔的分子遗传结构 总被引:2,自引:0,他引:2
采用1条小卫星引物M13(5’GAGGGTGGCGGTTCT3’)和2条微卫星引物(GTG)5、(GACA)4,对Vc—Ⅰ系、Vc—Ⅱ系獭兔、日本大耳白兔(JWR)和青紫蓝(QZL)4个品系各8只,总计32个个体的遗传结构进行了DNA指纹分析。结果,3条引物的扩增产物都呈现良好的多态性和稳定性;对每个品系混合DNA池进行分析,计算出了4个品系间及32个个体间的共有带率及遗传距离指数,通过聚类分析,得出各品系间和个体间欧式遗传距离,并绘制出4个品系间及各品系32个个体问的亲缘关系树状聚类图,从而初步建立了4个品系兔的SPAR指纹图谱。 相似文献
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给出非线性二阶阻尼微分方程新的振动准则,它们仅依赖于区间[t0,∞)的某些子区间序列的信息,不需要依赖于整个半直线,所得结果推广和改进了某些最近的结果. 相似文献
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Based on the distribution of 64 locations in wattle natural distribution in Australia and the data collected from 61 plantations in 30 more countries, 5 important factors were selected for determining the suitable climatic requirements for the growth of wattle. The experience of plantation wattle in China for over 30 years has been summarized. According to the comparison of climate and geographic distribution of wattle in China and other countries, China is a suitable country for growing wattle. Based on the results of our investigation, a division of suitable areas for growing wattle in China was made. Key points of planting method in each area were suggested. 相似文献