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71.
为使60Co辐照装置增加总活度为28878居里(1.07PBq)由7根活度不同的进口源棒的增源顺利启用,通过测定源到辐照位置的重复性为0.14%<1%,符合标准。测定从铁皮盖板到源中心的高度为90.3cm。五次升源所得剂量率(Gy/min)分别为:11.4、10.95、10.98、10.89、10.87,相对偏差为0.55%<1%.说明辐射场空间剂量率精确性高。计算辐照场空间分布的不均匀度U0=Dmax/Dmin=1.46(U0<1.5),表明在同一参考面上,辐射源剂量场剂量分布符合要求。  相似文献   
72.
The genomes of U.S. bluetongue viruses, an Australian bluetongue virus, and three other related orbiviruses were analyzed by polyacrylamide gel electrophoresis. The genomes were comprised of ten segments of double-stranded (ds) RNA. Estimates of the molecular weights of the dsRNA segments revealed that the U.S. bluetongue serotypes were remarkably similar. Although the dsRNA profiles of the viruses exhibited common segments, each virus had a distinct dsRNA profile. The usefulness of the genome analysis as a diagnostic tool for identification and for epidemiologic studies is discussed.  相似文献   
73.
Hyperthermia is a form of a cancer treatment which is frequently applied in combination with radiotherapy (RT) to improve therapy responses and radiosensitivity. The mode of action of hyperthermia is multifactorial; the one hand by altering the amount of the blood circulation in the treated tissue, on the other hand by modulating molecular pathways involved in cell survival processes and immunogenic interactions. One of the most dominant proteins induced by hyperthermia is the major stress-inducible heat shock protein 70 (Hsp70). Hsp70 can be found in the blood either as a free-protein (free HSP70) derived from necrotic cells, or lipid-bound (liposomal Hsp70) when it is actively released in extracellular vesicles (EVs) by living cells. The aim of the study was to evaluate the levels of free and liposomal Hsp70 before and after treatment with RT alone or hyperthermia combined with radiotherapy (HTRT) in dogs and cats to evaluate therapy responses. Peripheral blood was collected from feline and canine patients before and at 2, 4, 6 and 24 h after treatment with RT or HTRT. Hsp70 enzyme-linked immunosorbent assays (ELISAs) were performed to determine the free and liposomal Hsp70 concentrations in the serum. The levels were analysed after the first fraction of radiation to study immediate effects and after all applied fractions to study cumulative effects. The levels of free and liposomal Hsp70 levels in the circulation were not affected by the first singular treatment and cumulative effects of RT in cats however, after finalizing all treatment cycles with HTRT free and liposomal Hsp70 levels significantly increased. In dogs, HTRT, but not treatment with RT alone, significantly affected liposomal Hsp70 levels during the first fraction. Free Hsp70 levels were significantly increased after RT, but not HTRT, during the first fraction in dogs. In dogs, on the other hand, RT alone resulted in a significant increase in liposomal Hsp70, but HTRT did not significantly affect the liposomal Hsp70 when cumulative effects were analysed. Free Hsp70 was significantly induced in dogs after both, RT and HTRT when cumulative effects were analysed. RT and HTRT treatments differentially affect the levels of free and liposomal Hsp70 in dogs and cats. Both forms of Hsp70 could potentially be further investigated as potential liquid biopsy markers to study responses to RT and HTRT treatment in companion animals.  相似文献   
74.
梁金菇多糖诱导白血病细胞株HL-60凋亡的研究   总被引:3,自引:0,他引:3  
目的:观察梁金菇多糖对自血病细胞株HL-60凋亡的影响。方法:HL-60细胞与不同浓度的梁金菇多糖共同孵育5d后,采用荧光显微镜与透射电镜观察细胞形态及结构、DNA凝胶电泳观察“阶梯状”条带、流式细胞仪测定凋亡率。结果:细胞出现核碎裂、核溶解,凋亡小体形成等典型的凋亡形态学变化。结论;梁金菇多糖能诱导HL-60细胞发生典型凋亡。  相似文献   
75.
A study carried out for assessment of acaricide for control and how to show resistance of hard tick (Ixodidae) with some types of acaricide which available in Sulaimani marked froro February to April 2012, isolated 80 cattle (local breed) naturally infested with hard tick. Six hundred and fifteen ticks min7 tick/cattle including three genera species were collected and identified, the highest Boophilus spp. followed by Hyalomma spp., and Rhipicephalus spp. were less frequent species collected. Experimental cattle divided into four groups each group content 20 cattle, treatment with four types acaricide and their average of infestation in cattle with Boophilus spp. 33 (41.25%) as the commonest, followed by Hyalomma spp. 31 (75.38%), Rhipicephalus spp. 11 (13.75%) and 5 (6.25%) found mixed infested with Boophilus spp. and Hyalomma spp. 65 (81.3%) of cattle samples had emaciation and skin lesions. According to site of infestation, it showed that inguinal region was the most common predilection site for the ticks. Observed the genera Boophilus spp., there were highly significant differences (12.52%) between different tick species when calculated by general test (LSD). The objective of this study was to estimate and compare these acaricide to control hard tick, and there was highly significant relation between different species of hard ticks when treated by these acaricide, according to the chi-square tests. The activities of the acaricide through the time of application were different on the tick genera species. Diazinon (60%) and carbamate (saven 85%) has been a greater degree than other acaricide resistance, while shows the activity of both acaricide injectable ivermactin and cypromethrein through the early time on all species. The results of the study otherwise provide encouraging possibilities for the potential use recommended dose with both acaricide ivermactin-l% and cypromethrine-10%.  相似文献   
76.
木材光引发自由基规律的研究   总被引:2,自引:0,他引:2  
木材在~(60)Co γ射线辐射下引发g值为2.019、2.029、2.027、2.016、1.999等几种自由基。ESR主谱自由基浓度远大于机械自由基。并与树种、辐射剂量等有关。主谱自由基相对强度随剂量x按指数率Y=1-e~(-ax)上升,当剂量增加到100KGy时趋于饱和,根据福建21个常见树种测试有明显的规律性。  相似文献   
77.
采用2000γ、3500γ、5000γ、6500γ、8000γ5个等级的60Coγ射线对甘蔗种芽进行电离辐射处理,观察对甘蔗生长发育的影响及苗期辐射形态变化,发现随着辐射剂量的增加出苗率明显下降,生长亦严重受阻,并发生矮化苗,茎色改变,心叶不抽出,株型变化等多种辐射形态变化。3500γ以上的处理总变化数均在50%以上,尤以5000γ以上处理总变化率高,但差异不显著。初步认为蔗芽辐射育种的剂量范围为3500-8000γ,尤以3500-6500γ1为宜。  相似文献   
78.
本文将^60Co-γ射线进行辐射诱变育种的技术首次应用于长毛明对虾的遗传育种过程,初步探讨了长毛明对虾的亲体及幼体在^60Co-γ射线下不同诱变剂量的生物学效应,并通过产卵量、孵化率、存活率及亲虾的活力等数据,对辐射诱变剂量进行筛选,确定辐射诱变育种过程中辐射剂量的适宜范围。实验数据通过SPSS11.0进行单因素方差分析以及线性回归分析,研究结果显示诱变剂量同长毛明对虾幼体各性状指标有显著的相关关系(R^2〉0.90),各个实验组的孵化率以及存活率都随着诱变剂量的增加而呈现出相应的下降趋势,长毛明对虾进行辐射诱变适宜剂量的范围应在1Gy-10Gy之间,而有关诱变个体的胚胎发育和遗传分析还需进一步的研究。  相似文献   
79.
[目的]证实小鼠胎儿成纤维细胞中钙调蛋白 (calmodulin,CaM) 基因参与热应激诱导型热休克蛋白70(Hsp70)的基因表达并明确其作用条件.[方法]取12.5 d孕鼠胚胎制备成纤维细胞(MEF),上述细胞随机分为对照组和热应激组:对照组在37℃条件下培养,热应激组包括I组(39℃、0.5 h),Ⅱ组(39℃,1 h),Ⅲ组(39℃,1.5 h),Ⅳ组(41℃、0.5 h),V组(41℃、1 h),Ⅵ组(41℃、1.5 h);每组3个重复.将选择的热应激组和对照组细胞分别加入不同浓度(25、50及100 mm=ol·L<'-1>)钙调蛋白拮抗剂W7,运用RT-PCR检测Hsp70、CaM mRNA表达量.[结果] 39℃和41℃热应激组Hsp70 mRNA表达量显著高于常温对照组(P<0.05):39℃应激1h的Hsp70 mRNA表达量极显著高于其它各组(P<0.01);39"C应激0.5 h和1 h CaM mRNA表达量极显著高于其它各组(P<0.01);41℃热应激组的CaM mRNA表达量与常温对照组比较差异不显著(P>0.05).在培养液中加100 mmol·L<'-1> W7、分别于37℃和39℃处理1 h后,其成纤维细胞的Hsp70 mRNA表达量极显著低于相应对照组 (P<0.01).[结论]中度热应激条件下,Hsp70和CaM基因表达量呈正相关,且39℃应激1 h可以显著诱导Hsp70和CaM基因表达;CaM通过某种途径参与了Hsp70基因表达.  相似文献   
80.
以飞思卡尔公司基于ARM Cortex-M4内核的K60系列微控制器为例,设计了一种具有较好可移植性和重用性的UART底层驱动构件.测试结果表明该构件正确而有效.  相似文献   
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