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41.
The differentiation of benign vs. neoplastic lymph nodes impacts patient management. Specific sonographic features are typically considered when assessing lymph nodes in dogs. However, the usefulness of these criteria in distinguishing benign vs. malignant lymph nodes remains largely unknown, especially for deep lymph nodes. Our aim was to compare sonographic features in benign and neoplastic deep lymph nodes with the hope of identifying predictive criteria. Thirty‐one deep lymph nodes (16 mesenteric, 10 medial iliac, three hepatic, one sternal, and one cranial mediastinal) in 31 dogs were examined prospectively with B‐mode and Color flow Doppler. Lymph nodes were aspirated using ultrasound‐guidance and final diagnosis were established based on cytologic and/or histopathologic interpretation. Prevalence of each sonographic feature and combinations of two features was calculated for each group and compared using a χ2‐test or Student's t‐test for unequal variances. Ten lymph nodes were benign (hyperplastic and/or inflammatory) and 21 were neoplastic. All were hypoechoic, except for one neoplastic lymph node. Maximal short‐axis diameter (P=0.0006) and long‐axis diameter (P=0.01), and SA/LA ratio (P=0.008) were increased significantly for neoplastic (2.8, 5.5 cm, and 0.50, respectively) vs. benign (1.2, 3.8 cm, and 0.34, respectively) lymph nodes. The prevalence of other features was similar between groups. Doppler evaluation was possible in 77% of lymph nodes, but there was no significant difference between groups. When any two ultrasound features were combined, the only difference between benign and neoplastic lymph nodes was for the combination of contour regularity and appearance of the perinodal fat (P=0.03).  相似文献   
42.
The herniation of intervertebral disc material into the vertebral body, known as Schmorl's nodes, is a well described disease process in man. Schmorl's nodes have not until now been described in the dog. This paper describes intravertebral disc herniation in the dog based on five patients taken from a retrospective study of dogs suspected of having cauda equina syndrome. The significance of intravertebral disc herniation in the dog at this time is that they indicate a disturbance in the vertebral endplate, they present definite radiographic signs, should be considered in patients with ostecohondrosis, and remain a possibls etiology for fibrocartilaginous emboli. Back pain is a common sign in people when Schmorl's nodes were the only pathologic findings. The common signs of palpatory pain in the lumbosacral region of the dogs in this report is noted but cannot be directly correlated at this time to the intravertebral disc herniation; however, it is suspected in two of the cases.  相似文献   
43.
陈世一 《油气储运》1998,17(2):18-21
当安装于罐顶上的呼吸阀失灵,或罐内液体的汽化速度增大而又不能及时排放时,罐内的压力增高,部分罐底可能会离开基础而发生罐底提离现象。此时,在下节点处存在着较大的应力,甚至会造成油罐在下节蹼处的破坏。  相似文献   
44.
海狸鼠淋巴结的解剖及组织形态结构的初步研究   总被引:1,自引:0,他引:1  
通过对健康成年海狸鼠淋巴结的初步研究发现 :海狸鼠的淋巴结被膜较薄 ,小梁不发达 ;淋巴小结数量较多 ,呈椭圆形 ,细胞排列密集 ,胞核染色较深 ,生发中心不明显 ,皮窦和髓窦相对发达。  相似文献   
45.
利用大型稀疏矩阵的处理技术,用一维数组压缩存贮管网方程F(H)=0的Jacobi矩阵J(H),并应用图论方法进行管网图节点标号的优化,以节省管网分析计算所需的计算机存贮量及计算时间.  相似文献   
46.
给定结点组xk=kπ/σ(σ>0,k∈Z),对于正整数m1相似文献   
47.
膜荚黄芪子叶节植株再生体系的建立   总被引:2,自引:0,他引:2  
以膜荚黄芪无菌苗子叶节为外植体,建立了简单、高效和稳定的膜荚黄芪再生体系。结果表明:不定芽诱导的最适培养基是MS+6-BA 1.0mg/L+NAA 0.10mg/L,每个子叶节外植体平均出芽数为3个以上,再生频率达75.5%;生根最适培养基为1/2MS+IBA 0.5mg/L;移栽后成活率达75%以上。  相似文献   
48.
以塑料大棚栽培的厚皮甜瓜品种‘翠雪5号’为试验材料,探讨不同留瓜节位对不同节位叶片的生理生化指标、单果重以及可溶性固形物含量的影响。结果表明,‘翠雪5号’在第16节位留瓜时,可溶性蛋白(Pr)含量和叶绿素(Chl)高于第13节位留瓜,丙二醛含量(MDA)和愈创木酚过氧化物酶(POD)活性低于第13节位留瓜。然而,不同留瓜节位还会影响甜瓜植株衰老进程,对果实产量和品质有着重要的影响。一般来说,同一个品种春季栽培比秋季栽培的坐瓜节位要高2个节位左右,这样结出的瓜不仅果形好且大、产量高,糖度也高。  相似文献   
49.
Though identification of lymph nodes is essential in staging cancer patients, little has been reported about the CT features of canine abdominal lymph nodes. The purpose of this retrospective study was to describe the visibility, location, and characteristics of abdominal lymph nodes in abdominal CT studies of dogs considered unlikely to have lymphadenopathy. The relationship between the number of identified lymph nodes and intraabdominal fat ranking, body weight, and slice thickness was also investigated. A total of 19 dogs were included. At least two jejunal lymph nodes and both left and right medial iliac lymph nodes were identified in all dogs. Colic lymph nodes were not identified in any of the dogs. Visualization of all other lymph nodes varied. There were significantly more lymph nodes visible in dogs with more intraabdominal fat (P < 0.0001). No correlation between the number of identified lymph nodes and body weight (P = 0.64) or slice thickness (P = 0.76) was found. Though most of all identified lymph nodes had an elongated shape, a rounded shape was most common in splenic, pancreaticoduodenal, renal, ileocolic and caudal mesenteric lymph nodes. Most lymph nodes had a homogeneous structure before and following the intravenous administration of contrast medium. Some lymph nodes had a slightly irregular structure or were relatively more hyper attenuating in the periphery than centrally before and/or after contrast administration. Mean attenuation before contrast was 37 Hounsfield Units (HU) (range 20–52 HU), and 109 HU after contrast (range 36–223 HU). Findings indicated that the CT visibility, characteristics of different abdominal lymph nodes may be variable in dogs.  相似文献   
50.
郑秋丽 《绿色科技》2013,(7):112-114
从总体分区和布局、历史变迁、景观格局以及重要的景观节点等方面对华南植物园凤梨园进行了全面的阐述,同时也展示了一种基于热带植物的岭南庭院式园林的造景方式。  相似文献   
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