病原物侵染过程(infection process)就是病原物与 寄主植物可侵染部位接触,并侵入寄主植物,在植 物内繁殖和扩展,然后发生致病作用,显示病害症 状的过程,也是植物个体遭受病原物侵染后的发病 过程。 ·侵染过程一般分为四个时期:接触期、侵入期、 潜育期、发病期。 第一节 接触期 contact phase 第二节 侵入期 第三节 潜育期 第四节 发病期 symptom appearance phase

Amoebiasis Amoebiasis is a disease of the large intestine resulting from infection with the protozoan entamoeba histolytica

susceptible host, a series of coordinated events must rcumvent both innate and adaptive immunity. One of the first and most important features of host innate immunity is the barrier provided by the epithelial surfaces of the skin and the lining of the gut. The difficulty of penetrat- ing these epithelial barriers ensures that most pathogens never gain productive entry into the host. In addition to pro viding a physical barrier to infection, the epithelia also pro duce chemicals that are useful in

What does a pathogen have to do? Infect (infest) a host Reproduce(replicate) itself Ensure that its progeny are transmitted to another host

动物传梁病等 感染( infection),又称传染,是病原体对动物体的 种寄生过程。 在漫长的进化过程中,有些寄生物与动物体宿主之 间达到了互相适应,互不损害对方的共生状态.例 如肠道中的大肠杆菌和某些真菌。但这种平衡是相 对的,当某些因素导至宿主的免疫功能受损(如艾 滋病)或机械损伤使寄生物离开其固有寄生部位而到 达其不习惯寄生的部位,如大肠杆菌进入腹腔或泌 回本节尿道时,平衡不复存在而引起宿主的损伤,则可产 生机会性感染

Why Serious deformities Unbalance of facial growth Error in operation Shortcoming of operation design Infection and Split open

Purulent Meningitis Acute infection of central nervous system(CNS). 90% of cases occur in the age of 1 mo-5yr. The inflammation of meninges caused by various bacteria. Common features in clinical practices include: fever, increased intracranial pressure, meningeal irritation

草鱼出血病病毒感染鱼肾(C1k)单层细胞后,产生明显的细胞病变,其繁殖周期为 2一3天。病毒增殖的上升期在感染后的12—48小时。28°下,当感染复数(Multiplicity of Infection简称mo为0.05pfu/ce11时病毒滴价可达1.78×101PU/ml,不同 温度(25°℃、28°℃、30C)下通气培养,测定病毒滴价略有差异

• Viral hepatitis is a group systemic infection affecting the liver predominantly caused by 5 kinds of viruses at least • Five hepatotropic hepatitis viruses are responsible for the vast majority of hepatitis cases(classical) : Hepatitis A virus (HAV) Hepatitis B virus (HBV) Hepatitis C virus (HCV) Hepatitis D or delta virus (HDV) Hepatitis E virus (HEV)

AIDS Complications 艾滋病并发症 Infection 感染 Symptoms 症状 Diagnosis 诊断