一些怎样研究生论文
Abstract
The objective of this study was to investigate the current prevalence of Hepatitis E Virus (HEV) in swine livers in China. Five hundred and eighty one swine liver samples and 139 serum samples were collected from slaughter-houses, these swine were purchased from Heilongjiang, Jilin, Liaoning, Hebei, Beijing and Henan. Six experiments were designed to provide enough evidence.
1. Immunohistochemical staining was carried out to detect HEV Ag in Slaughtered swine liver. The results showed that positive material sporadicly distributed in liver cells with liver cytoplasm presented negative reaction at the marginal of liver. Away from the marginal of liver positive objects extensively distributed in liver cells with little cell nucleus presented positive reaction. Inflammatory cells showed negative reaction in interstitial. Endothelial cells of interlobular bile duct veins and arteries showed positive reaction in the portal area of liver. Negative control doesn’t present positive reaction. It was found that 536 out of 581 liver samples were positive for HEV Ag. The positive rate was 92.25%.
2. Histopathologic observation on positive tissues for immunohistochemical staining approached dependability between pathological changes and HEV Ag distributed in liver. The results showed that positive tissues for HEV Ag immunohistochemical staining presented different pathological changes : sporadic denaturation and karyopyknosis of liver cell, infiltration of lymphocytes, hyperplasy of bile canaliculus and fibrous tissue in the portal area. It was found that total 581 liver samples have been affected. The incidence pathological changes were 100%.
