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1.
Ultrasonography and MRI have become valuable tools for imaging of tendon injuries. The current study examines the histopathologic basis for the imaging abnormalities. Five injured equine forelimbs and two normal contralateral limbs were studied with high resolution real time ultrasound and MRI. Histologic sections were made and correlated with the diagnostic images. All lesions were readily seen by both modalities. Lesions characterized by hemorrhage, edma, and cellular infiltration were sonolucent on ultrasound and bright on MRI images. MRI returned to normal as fibrogenesis ensued. Ultrasound images remained abnormal until fibrillar reallgnment occured with completion of the healing process. High resolution real time ultrasound and MRI both accurately reflect the tissue abnormalities in acute tendon injuries. The injured horse does appear to be an effective model for correlative imaging studies of tendon injuries.  相似文献   
2.
Inherited canine copper toxicosis is a serious problem in Bedlington terriers and West Highland White terriers, and may also be a problem in other less-studied breeds. Affected dogs become ill at midlife with progressive and ultimately fatal liver disease. Treatments for removal of copper and prevention of copper accumulation are available, but are most effective if begun before the dog becomes ill. Until recently diagnosis has not been available until the dog is 1 year of age, and then only by an invasive liver biopsy with determination of liver copper concentration. The authors studied the use of 64copper for early diagnosis of canine copper toxicosis. Two procedures were evaluated. The first involved measuring the concentration of 64copper in blood 24 hours after oral administration of the radioisotope. At this time, 64copper was associated primarily with ceruloplasmin secreted into the blood by the liver. This procedure is useful in the diagnosis of the human counterpart, Wilson's disease. However, the authors found it to be nondiscriminatory between affected and unaffected dogs. In contrast, the second procedure, which involved measuring 64copper excreted in stool during 48 hours after an intravenous dose of radioisotope, yielded results that differentiated most affected and unaffected dogs.  相似文献   
3.
A 13-year-old neutered female Yorkshire terrier presented with a history of progressive episodic weakness and disorientation of 4 months duration. Physical and neurologic examinations were normal at presentation. Abdominal ultrasound revealed a mass involving the right adrenal gland. Standard planar scintigraphy was performed at 4, 18, and 24 hours after intravenous injection 185 MBq (5mCi) of 123I-labeled metaiodobenzylguanidine (123I-MIBG). An area of focal intense uptake was identified in the area of the right adrenal gland. A pheochromocytoma was confirmed histologically after surgical excision.  相似文献   
4.
研究了陆地棉主要性状对混选—混交育种体系的响应。两轮群体提高了产量、早熟性和降低了麦克隆值的平均数;扩大了纤维品质的变幅;增加了高产株率,但对改进抗枯黄萎病性不明显。一轮群体的效果低于二轮。两次混交扩大了产量和纤维品质的变幅,增加了正末端的个体频率。一次混交的作用不及两次。早代混选相对缩小了群体变幅。一次混交后再经两代开放授粉和对一轮群体再混选,均表现出有益的反响。  相似文献   
5.
Ten, anesthetized dogs were instrumented with three pulse oximeter probes; two lingual transmittance probes and one rectal reflective probe. Arterial oxygen desaturation was produced by decreasing the inspired oxygen concentration. Hypotension was produced with an infusion of nitroprusside. Simultaneous pulse oximeter readings (SpO2) were compared to co-oximeter measured arterial saturation (SaO2) collected over a range of SaO2 (50–100%) and mean arterial pressures (40–100mmHg). Each of the monitors and means of evaluating SpO2 studied provided accurate SpO2 measurements over a range of mean arterial pressure from 40–100mmHg. All of the monitors tested tended to overestimate the SaO2 when the arterial saturation was less than 70%.  相似文献   
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7.
高产棉花太阳辐射能利用率及干物质分配规律研究   总被引:6,自引:0,他引:6  
通过对1988~1989年高产棉花栽培试验结果进行分析发现,棉花的太阳辐射利用率在叶面积系数小于2.0时随叶面积系数的增加而线性增加,大于2.0时增加变缓。从生育时间看,7月中旬前太阳辐射利用率指数上升,7月中旬至8月底相对稳定在1.2~1.4克/兆焦左右,9月以后又不同程度线性下降。生长季内子棉太阳辐射经济效率1988和1989年分别为0.14和0.15克/兆焦。收获指数与最大叶面积系数呈显著负相关;盛花期之前棉株各器官之间的同伸关系或明显,盛花期后器官的生长相互间无明显的确定性关系。如能调节密度与叶面积系数的关系,使得既提高5~6月的辐射能利用率,同时使7~8月叶面积系数维持在3.0~3.5的适宜范围内,9~10月群体又不早衰,则有利于获得高产。  相似文献   
8.
Canine inflammatory mammary cancer (IMC) has been proposed as a model for the study of human inflammatory breast cancer (IBC). The aims of this study were to compare the immunohistochemical expression of aromatase (Arom) and several hormone receptors [estrogen receptor α (ERα), estrogen receptor β (ERβ), progesterone receptor (PR) and androgen receptor (AR)], in 21 IMC cases vs 19 non‐IMC; and to study the possible effect of letrozole on canine IMC and human inflammatory breast cancer (IBC) in vitro using IPC‐366 and SUM‐149 cell lines. Significant elevations of the means of Arom Total Score (TS), ERβ TS and PR TS were found in the IMC group (p = 0.025, p = 0.038 and p = 0.037, respectively). Secondary IMC tumours expressed higher levels of Arom than primary IMC (p = 0.029). Non‐IMC PR‐ tumours contained higher levels of Arom than non‐IMC PR+ tumours (p = 0.007). After the addition of letrozole, the number of IMC and IBC cells dropped drastically. The overexpression of Arom found and the results obtained in vitro further support canine IMC as a model for the study of IBC and future approaches to the treatment of dogs with mammary cancer, and especially IMC, using Arom inhibitors.  相似文献   
9.
本文主要综述了我国近20年来棉花分子育种在理论基础、技术方法、育种机理以及新品种培育等方面研究取得的成就及新进展,并讨论了棉花分子育种的发展方向  相似文献   
10.
本文通过聚集度指标(如:C、K、C_A、I、I_δ、)测定,以及Iwao’线性回归、Taylor’sS ̄2一回归和格局纹理分析,结果表明,棉花烂铃空间格而在一切密度下都呈聚集型,且聚集强度随烂铃密度的升高而增加,其空间格局的基本成分是疏松的个体群,其大小约为2~5株棉花,平均约含2.84个烂铃个体,且个体群内的个体呈随机分布,经μ检验和方差分析,双对角线5点式、棋盘式和平行跳跃式等3种取样方法均适用于棉花烂铃田间调查,尤以双对角线5点式为佳,用双对角线5点式应样法调查的最适抽样数:一般病情普查至少10个样方(每样方系5株棉花),系统测报和科研调查为20~30个样方。最后给出了棉花烂铃平均密度的零频率简易估计模型。  相似文献   
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