微生物大题-英文

2.Pass mechanism of cholera pathogenic:霍乱1)pathogenic factor:invasiveness: flagellum, pili;cholera enterotoxin: contain A and B subunits. A subunit-Ag weak, active unit, enters the cell, stimulates adenylate cyclase-cAMP↑-secreting effect↑-severe diarrhea; B subunit-Ag high, bound unit, attaches to receptor on epithelial cells of small intestine.2)mechanism:Organisms-oral route(contaminated water, food)-stomach-attach to the small intestine epithelialcells(non-penetration)-multiplication-cholera enterotoxin-adenylate cyclase-cAMP concentration↑-secreting effect↑-severe diarrhea(rice-water stools)-rapid dehydration and hypovolaemic shock低血容量休克-die in 12~24 hours. Ps. Transmission: polluted water and food, by mouth3.Pass Clostridium tetani- pathogenesis破伤风1)condition:Wound+sporeDeep, narrow and contaminated by soil;Necrotic坏死的tissue;Companied with aerobe or facultative anaerobe infection.2)pathogenic substance:Tetanospasmin破伤风痉挛毒素- neurotoxin: proteinTetanolysin破伤风溶血毒素3)mechanism:根据课件整理一下Spores-vegetative bacteria细菌繁殖体-grow locally-tetanospasmin-( along nerve fiber/ blood)-anterior horn cells of spinal cord, binds to ganglioside receptor神经节苷酯受体and blocks release of inhibitory mediators-cause convulsive痉挛的contraction of voluntary muscle.4.Pass dsDNA病毒的复制周期答：复制周期依次包括：吸附。

穿入。

脱壳。

生物合成。

组装、成熟和释放。

Replication cycle: adsorption-penetration-uncoating-biomolecular synthesis-assembly-maturation-release5.Pass HIV致病机制：Pathogenesis:Gp120 of HIV select CD4 molecule of T4 cells;Viruses multiply in T4 cells;Cell-mediated immunodeficiency;Opportunistic infections and tumor occurs;DeathHIV损伤CD4 T细胞的机制：①导致CD4 T细胞融合，最终导致细胞的溶解；②CTL对CD4 T细胞的直接杀伤作用，抗体介导的ADCC作用，NK细胞的杀伤作用；③诱导CD4 T细胞细胞凋亡；④HIV复制产生大量未整合的病毒DNA，抑制细胞正常的生物合成；⑤HIV可作为超抗原激活大量CD4 T细胞。

6，gp41与细胞膜上MHC二类分子有同源性homology，诱导产生具有交叉反应的自身抗体，致使T细胞损伤。

Destruction of T4 cells is achieved by:① Viral replication②Syncytium合胞体formation via membrane gp120 binding to cell CD4 antigen③Cytotoxic T cell lysis of infected cells④Cytotoxic T cell lysis of T4 cells carrying gp120 released from infected cells⑤ Antibody-dependent cell cytotoxicity.⑥Induce appoptosis.8.Pass functions of special cell structure of bacteria:1) capsule: slime layer outside the cell wall, composed of polysaccharide or polypeptide.Functions: anti-phagocytosis; adherence; protect from lesions by harmful substances; anti-dry; antigenicity2) flagellum: originate from cell membraneFunctions: motility; antigenicity(H antigen); pathogenicity: some bacteria3) pilus:Common pilus: adhere to surface of cell, associated with pathogenicitySex pilus: transfer genetic material (DNA) during bacteria conjugation4) spore: resting form, forming: inadequate nutritionFunction: highly resistant to heat, chemicals, dry9. Pass streptococcus 致病物质及主要疾病：1) invasivenessAdhesion: LTA(脂磷壁酸)、M protein-----adhere to sensitive cell2) enzyme:Hyaluronidase: split hyaluronic acid—bacteria spreadStreptokinase: lyse fibrin, prevent plasma clotting—bacteria spread Streptodornase(链道酶): resolve DNA—bacteria spread3)toxin-exotoxinStreptolysin(hemolysin)链球菌溶血素: destroy blood cellsPyrogenic exotoxin致热外毒素：superantigen, cause scarlet fever猩红热Disease:Pyogenic infection(化脓性感染)Toxin disease: scarlet feverNon-pyogenic infection(1) rheumatic fever(2) acute glomerulonephritis10.Pass what is plasmid? It’s features.plasmid is the extrachromosomal genetic elements which is small circular double-stranded DNA molecules. They are capable of self-replication and contain genes that determine many properties.Features:1)extra-chromosomal genetic material circle2)ds DNA3)dispensible(非必需的)4)replicated independently5)carry genetic information6)control a wide range of function to bacteriafactor F—control sex pilifactor R—control drug resistance7)transferred between bacteria11.Pass what is latent infection. Take HSV as example.Latent infection: virus is usually not detectable but patient may have periodic out-breaks of disease. In this infection, the acute disease is followed by an asymptomatic period during which the virus remains in a latent state.12.Pass distributions and functions of normal flora1)distributions: skin, oral cavity, intestinal tract, vagina2)functions:①antagonism: biological barrier②nutrient synthesize: VB, VK③immune: enhance and develop the maturation of immune system④anti-caducity(抗衰老)⑤anti-tumor13.Pass 结核分枝杆菌的传播途径和致病因子：1)route: by respiratory tract, digestive tract or damaged skin.2)pathogenic substances:①lipid：A.cord factor: associated with virulence; inhibit migration of leukocyte to form chronic granuloma; bind to mitochondrial membranes, influence the cell respirationB. Phosphatide磷脂: stimulate monocytes proliferation-form tubercleC. Wax D: act as an adjuvant, cause DTHD. Sulfatides硫酸脑苷脂: inhibit the fusion of phagosome and lysosome②proteintuberculin结核菌素Tuberculin+waxD-DTHAg-Ab(no protection)③polysaccharide :combine with waxD- cell filtration④mycobactin(分枝菌生长素)致病机制加上这句话：No endotoxin, exotoxin, no capsule, and no invasiveness enzyme致病机制：No endotoxin, exotoxin, no capsule, and no invasiveness enzyme.加上上面的致病物质Primary tuberculosis: organism-respiratory tract-pulmonary alveoli-lesion-lymph nodes-swelling-fibrosis-natural curePost primary tuberculosis: organism-infection again-inflammation-necrosis坏死-tubercle结节-fibrosis纤维化14.Pass HBV基因组及其编码的蛋白。