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The pathogenesis of paraesophageal empyema in dogs and constancy of radiographic and computed tomography signs are linked to involvement of the mediastinal serous cavity
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Karine Gendron Sean P. McDonough James A. Flanders May Tse Peter V. Scrivani 《Veterinary radiology & ultrasound》2018,59(2):169-179
The mediastinal serous cavity is a normal anatomic space in the caudal mediastinum. Aims of this anatomic and case series study were to describe the signs of pathologic expansion of the mediastinal serous cavity observed during computed tomography (CT), review the underlying anatomy, perform a literature review, and evaluate the medical records of several dogs with mediastinal serous cavity empyema (paraesophageal empyema). The mesothelial lined mediastinal serous cavity is a cranial extension of the omental bursa, separated from the peritoneal cavity by the diaphragm, in the dorsal part of the caudal mediastinum, to the right of the esophagus, between the heart base and diaphragm. In five adult, large‐breed dogs with surgically and histologically confirmed paraesophageal empyema, macroscopic plant material was found at surgery in two dogs, adherence to adjacent lung was present in three different dogs, accessory lobectomy was performed in two dogs with subacute‐chronic pyogranulomatous pneumonia, and one dog had concurrent pyothorax and mediastinitis, but none had esophageal abnormalities. This study expands our understanding of the pathogenesis and basis for the imaging appearance of paraesophageal empyema in dogs by clarifying the underlying anatomic structures that direct development of this condition. The term empyema accurately describes this condition because the purulent material accumulates within an existing body cavity. The study also provides initial evidence that the development of paraesophageal empyema might be due to local extension of lung disease, such as foreign body migration or pneumonia. Computed tomography was helpful for diagnosis, assessing size, and determining the spread of disease. 相似文献
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Young-Ha SHIN Shunta SHIRAISHI Kiyoaki NARABARA Asaki ABE Yasuhiro KONDO 《Animal Science Journal》2012,83(2):156-161
Estrogen has been reported to act on B cell genesis in the bursa of Fabricius of chick embryos. In this study, we attempted to demonstrate the hypothesis that B cell genesis is controlled by estrogen receptor (ER) in the bursal cells and steroidogenic enzymes synthesized in the bursa. We previously reported the presence of estrogen receptor α (ERα) in the bursa during the late stage of embryogenesis and an increase in the expression of ERα messenger RNA (mRNA) between the 13th day and 16th day. The number of ER-positive cells was maximal on the 16th day. In the present study, ER-positive cells in the bursa during the late stage of embryogenesis increased 4 h after β-estradiol treatment on the 14th to 18th day. The concentration of β-estradiol in the embryonic bursa increased. These results suggest that this stage of embryogenesis is critical in B cell development in the bursa in connection with the effect of estrogen treatment. Our findings also showed that the mRNA expression of five steroidogenic enzymes occurred in the bursa of chick embryos. These results suggest that estrogen is synthesized in the embryonic bursa and estrogen acts on the bursal cells in a paracrine fashion. 相似文献
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肉雏鸡与蛋雏鸡法氏囊生长发育规律的探讨 总被引:1,自引:0,他引:1
通过测量不同日龄肉鸡与蛋鸡的法氏囊指标研究其生长发育规律。肉鸡分别在10个不同日龄随机选取10只健康鸡。蛋鸡分别在12个不同日龄随机选取健康的公鸡、母鸡各10只。宰杀后,摘取法氏囊称重,测量其长、宽、高,并制作石蜡组织切片进行HE染色,然后显微镜下测量法氏囊滤泡的长、宽、皮质及髓质厚度。结果表明,肉鸡法氏囊重量随日龄的增长不断增加,到49日龄达到最大,其滤泡的生长也符合此规律;蛋鸡的法氏囊重量从1~68日龄不断增长,并且到68日龄时达到最大值,68~96日龄逐渐减小,其滤泡生长也符合此规律,而法氏囊指数与日龄和体重的增加呈现一定规律的正相关。 相似文献
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选择1日龄健康雏番鸭45只,随机分为3组,分别喂以每kg含锌离子20mg、40mg、200mg的饲料,饲养期为45d。于15日龄、30日龄和45日龄每组随机宰杀5只,取法氏囊、脾脏、胸腺,Carnoy法固定,甲苯胺蓝染色,显微镜观察肥大细胞数量的变化规律。结果表明:15日龄时,低锌日粮组鸭子胸腺和脾脏的肥大细胞数量均比另外两组高,(P〉0.05),而法氏囊中低锌日粮组肥大细胞数量比另外两组明显高(P〈0.01)。30日龄时,低锌日粮组鸭子胸腺、脾脏和法氏囊中肥大细胞数量均比高锌日粮组显著增多(P〈0.05),而与正常锌日粮组相比,差异不显著(P〉0.05)。45日龄时,法氏囊高锌日粮组与低锌日粮组和正常锌日粮组差异显著(P〈0.05);脾脏各组间差异不显著(P〉0.05),但高锌日粮组肥大细胞数量最多;胸腺低锌日粮组与高锌日粮组和正常锌日粮组差异极显著(P〈0.01)。因此,锌具有稳定免疫器官中肥大细胞数量的重要作用,但长时间添加高剂量锌反而会增加肥大细胞数量。 相似文献
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法氏囊是鸟类特有的器官,是B淋巴细胞成熟的场所.本研究分析了鸡胚早期发育过程的中法氏囊形态变化及增殖细胞核抗原PCNA表达变化.结果表明鸡胚6.5 d(E6.5)时,法氏囊开始出现在鸡胚泄殖腔的最深处,从最开始E6.5的一些小的囊泡发育成E8的一个大腔,E8~E10,法氏囊继续发育.从E11开始,法氏囊开始出现一些小的皱褶,E11~E18,这些小的皱褶逐渐变得清晰,并贯穿整个法氏囊.在E9时,法氏囊轮廓形成,可以发现在表皮层和基膜层PCNA有着广泛的表达.统计分析表明表皮层的PCNA阳性率在100%左右,在整个发育早期几乎没有变化;而基层的阳性率随着胚胎的发育逐渐下降,在E9、E10、E11、E12、E14和E18表达率分别是97%、93%、71%、55%、56%和20%. 相似文献
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鸡胚胸腺和腔上囊的组织发生 总被引:4,自引:0,他引:4
鸡胚的胸腺原基发生于第Ⅲ、Ⅳ咽囊上皮,在E4(E4指胚胎发育到第4天)到E5胸腺的上皮分化成索状,进入咽囊的间质内。从E9至E10胸腺呈长索状,环绕颈静脉分布,胸腺开始区分出皮质、髓质及大叶,E12出现胸腺小体原基。从E15至E16皮质和髓质界限明显。大约F20至E21髓质中出现典型的胸腺小体,皮质主要被中、小淋巴细胞填充。在E6到E8上囊原基泄殖背面上皮间的小空泡合并成大空泡形成。从E11到E12腔上囊出现8条-11条叶状皱襞,粘膜面出现淋巴上皮芽。大约在E16至E17初级小叶增到16条-20条,小叶内巴滤泡的髓质形成。在E18至E21滤泡髓质内的淋巴细胞向单层上皮外移动形成皮质。滤泡的粘膜面分化出吸收上皮,滤泡间者称分泌上皮。 相似文献