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This paper studies the nineral composition,mineral phase transformation mech-anism and properties of hydration and hardening of the coloured cement by using x-ray diffractionanalysis and the x-ray diffraction analysis reliability is checked by using scanning electron mi-croscopy and infrared spectral analysis and other physical and chemical analysis methods.  相似文献   
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In this paper,we have studied the change law of the structural parameter of coal in Nan Tong Coal Mine with the increasing the temperature. At the same time, we explore the cause of the changes with the electron microscope and of infrared spectrum.  相似文献   
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The influence of body position on volume and x-ray attenuation of the lungs of three Beagles was investigated with computed tomography. In left and right lateral recumbency, the dependent lung had decreased volume and increased x-ray attenuation compared with ventral recumbency. Volume and x-ray attenuation of the nondependent lung, however, were unchanged. In dorsal recumbency, there was a vertical gradient of x-ray attenuation being increased dorsally and decreased ventrally compared with ventral recumbency where regional differences in x-ray attenuation were not found. Results indicate a risk of overlooking a mass in the dependent pulmonary parenchyma of dogs in lateral and dorsal recumbency. Regional differences in x-ray attenuation of the lungs of dogs can be avoided if the radiographs are obtained with the dog in ventral recumbency.  相似文献   
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选用健康家兔40只,取仰卧位保定,5%戊巴比妥钠溶液麻醉,对家兔胸部体层摄影技术进行了探讨。几何条件:使用直线轨迹时,曝光角度以20°为好;使用区域圆轨迹时,以12°为好。显示支气管的最佳层次()与胸厚(X)的回归方程(?)=0.739X-1.922。物理条件:kVP=胸厚(cm)+40+10(滤线器);mA及s:直线轨迹时100mA,0.3s;区域圆轨迹时20mA,2.8s。并对所拍摄的X线体层照片进行了分析,在显示胸部某一层面的结构上和对肺脏、支气管部位病变的诊断上,体层摄影有明显的优点,而麻醉对改善体层片的质量有一定作用。  相似文献   
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The purpose of this study was to evaluate the clinical safety of pamidronate when administered at a mean dosage of 1.0 mg/kg IV q28d in 33 tumor-bearing dogs. Biochemical tests of renal function were evaluated before each successive pamidronate treatment. Of 33 dogs treated with pamidronate, 1 dog had clinically relevant increases in serum creatinine and blood urea nitrogen concentrations. The biologic activity of IV pamidronate was assessed prospectively in 10 dogs with appendicular osteosarcoma and was assessed on reductions in urine N-telopeptide excretion (P = .042) and enhanced bone mineral density of the primary tumor measured with dual-energy x-ray absorptiometry (P = .024). Additionally, in these 10 dogs, pamidronate's therapeutic activity was supported by subjective improvement in pain control in 4 of the 10 dogs treated. IV pamidronate appears clinically safe in tumor-bearing dogs and may possess modest biologic activity for managing neoplastic complications associated with pathologic bone resorption.  相似文献   
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The objective of this study was to establish a technique for radiographic examination of the coxofemoral joint and adjacent bony structures in standing cattle. Left (or right) 30° dorsal-right (or left) ventral radiographic views of the coxofemoral joint region of standing cattle (n = 10) with hind limb lameness were evaluated retrospectively. In addition, an experimental study of oblique laterolateral views of the coxofemoral joint region of a bovine skeleton at angles of 15-45° was carried out to determine the optimal position for visualization of the hip region. In the 10 clinical patients, the bodies of the ilium and ischium, the acetabulum and proximal third of the femur could be assessed. Six of these cattle had fractures of the body of the ilium and body of the ischium, five with and one without involvement of the acetabulum, two had craniodorsal and one caudoventral luxation of the femur and one had a femoral neck fracture. The described laterodorsal-lateroventral radiographs of the hip region in standing cattle were suitable for assessing the coxofemoral joint, the proximal aspect of the femur and parts of the ischium, ilium and pubis. After testing the optimal angle on the skeleton, it was seen that distortion and superimposition were minimized by positioning the X-ray beam at an angle of 25° to the horizontal plane. It can be concluded that the described technique improves the evaluation of injuries of the coxofemoral region in cattle. With the appropriate angle, the technique can also be applied in recumbent cattle.  相似文献   
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鸡蛋壳质量与超微结构关系的研究   总被引:1,自引:0,他引:1  
研究使用常规方法测定蛋形指数、蛋壳相对重量、蛋壳强度和蛋壳厚度等蛋壳质量指标,使用X射线能谱仪测定蛋壳断面各层钙的相对含量,使用环境扫描电子显微镜观察蛋壳断面各层和内外表面的超微结构。结果表明:蛋壳强度与蛋壳相对重量、蛋壳强度与蛋壳厚度以及蛋壳相对重量与蛋壳厚度之间相关分别达到0.444(P<0.01)、0.700(P<0.01)和0.611(P<0.01),各相关系数不在同一水平。蛋壳各层钙的相对含量分别达到32.68%±8.62%、33.13%±6.58%和32.35%±.97%,之间差异不显著(P>0.05),几近匀质。环境扫描电子显微镜的观察发现不同强度的蛋壳,其各层和内外表面超微结构存在明显差异。由此得出:蛋壳超微结构的差异是蛋壳质量变化的重要影响因素。  相似文献   
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Pb在类芦组织和亚细胞中的分布规律和毒害效应   总被引:5,自引:5,他引:0  
通过研究类芦体内Pb在组织和亚细胞水平的毒害效应和分布规律,分析类芦对Pb的耐性机制,为了解类芦对重金属的富集能力、耐性机制及逆境生理提供理论依据。采用营养液培养的方法,以Pb为目标污染物,胁迫后测定类芦体内(分为根和叶)Pb在各亚细胞组分的含量,并分别通过扫描电子显微镜(SEM)和能谱透射电子显微镜(TEM-EDS)观察Pb在组织和亚细胞的分布以及对其损伤情况。结果显示:从组织水平来看,Pb胁迫下组织结构由排列整齐变为不规则,局部出现较大破损而形成一些碎片,并出现晶体堵塞导管的现象;从亚细胞水平来看,类芦根叶细胞均损伤,出现细胞壁模糊、线粒体减少、叶绿体肿胀等现象,在根部Pb主要分布于细胞壁(12.28 mg·kg~(-1))和以液泡为主的可溶组分(38.82 mg·kg~(-1)),而叶片中以可溶组分占比例最大(32.56%),且EDS元素分析也显示细胞内含有大量Pb。这些结果表明,类芦对Pb有一定的吸收富集能力,并可通过改变Pb在其组织和亚细胞水平的分布来降低毒害作用,因此类芦对重金属Pb有较强的耐性。  相似文献   
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