本文观察了1只38岁高龄的大熊猫多器官衰竭的病理学变化。病理剖检显示，该熊猫主要表现为实质器官充血、水肿和出血性变化；组织病理学检查发现，全身实质器官（除心、肺、脑外）均发生明显萎缩，胃、肠、肝、胰、肾等发生水肿变性或出血；此外，还观察到心肌纤维坏死后的瘢痕形成。结果表明，老龄大熊猫的多器官衰竭的病理学变化与其他动物相似；高龄大熊猫也易患心血管系统疾病，且具有较强的组织修复能力。

Histomorphologic changes of the lymphatic system of the liver and thoracic duct were examined. e diameters of lymphatic segments isolated from the thoracic ducts of ascitic and normal broilers at 32 to 37 days of age were measured using an optical micrometer measurement system. e histopathological picture of the segments of lymphatic tissue showed lymphatic cysts bilaterally along the posterior vena cava. e hepatic capsule manifested edema, thickening, and cellular proliferation. Microscopic changes in lymphatic vessels of the hepatic capsule include lymph embolism, and lymphatic plasma retention in lymphatic cysts. In some cases, distended lymphatic vessels exhibited protuberances, and lymph leaked from the lymphatic cysts into the surrounding swollen and degenerated endothelial cells of the thoracic duct. Sometimes, extensive endothelial cell loss was observed, and their exfoliated fragments were also seen. Marked dilatation of thoracic duct and lymph embolism, leaking of lymph, edema in some fibers and the enlargement of spaces between fibers, swollen intimas, and rupture and bleeding of the thoracic duct were also visible. e thoracic duct's long and short semi-axis, and the cross sectional area of the thoracic duct differed significantly between normal and ascitic broilers.

对感染伪狂犬病病毒（PRV）猪脑组织的MDA含量和SOD活性进行了检测。结果显示，猪感染PRV后脑组织MDA含量普遍升高，项叶、额叶、小脑、扣带回和海马与对照组比较，差异显著（P<0.05）；SOD活性与对照组相比额叶升高（P<0.05），而扣带回、海马显著降低（P<0.05）。结果提示，自由基介入了PRV的致病过程。

对22日龄健康AA肉鸡和新城疫野毒（NDV）感染肉鸡组织中丙二醛（MDA）含量和超氧化物歧化酶（SOD）活性研究结果显示：ND野毒感染病鸡心、肝、肾等组织MDA含量和s0D活性发生明显改变。结果提示，自由基参与了ND发生发展的致病过程，在NDV诱导的细胞凋亡过程中自由基可能起关键作用。

利用高能日粮常规饲养大群艾维因肉鸡的方法，获得自然肺动脉高压综合征（PHS）肉鸡病例。应用放射免疫分析方法，分别测定了2～6周龄正常组和肺动脉高压（PH）组肉鸡血浆及心、肝、肺、肾等组织中内皮素（endothelin-l，ET-1）的含量，并测定了腹水心脏指数（AHI）和平均肺动脉压（mPAP），同时还应用硝酸还原酶法测定了血浆中一氧化氮（N0）、一氧化氮合酶（NOS）水平。结果显示：PH组AHI、mPAP极显著高于正常组（P<O.01）；从3周龄开始，PH组ET-1水平开始显著或极显著高于正常组（P<0.05或P<0.01），6周龄时PH组血浆、肺脏和肾脏ET-2水平略为下降，但仍极显著高于正常组（P<O.01）；AHI、mPAP和ET-1均随肉鸡日龄的增长而升高；组织中ET-1含量高于血浆，肺组织中ET-1含量明显高于其它几种组织；mPAP变化与血浆ET-1含量变化之间存在显著正相关（P<0.05），但与N0相关性不显著；两组血浆NO、NOS水平均随日龄增长而升高，且PH组NO、NOS水平在后期显著高于正常组。本试验结果提示，ET-1、NO参与了肉鸡PH s的形成和发展过程，并在其中起着重要作用。