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101.
102.
革兰氏阴性菌外膜蛋白研究进展 总被引:14,自引:0,他引:14
外膜蛋白对细菌本身和宿主都具有重要的作用。本文综述了革兰氏阴性菌外膜蛋白的组成、结构、功能及遗传调控,外膜蛋白可作为大肠杆菌的克隆标志,在细菌的致病机理及免疫机理中都有重要作用,研制开发外膜蛋白疫苗具有广阔的应用前景,必将为细菌性疾病的防治提供有力的措施。 相似文献
103.
细胞凋亡与细胞坏死比较的研究进展 总被引:5,自引:0,他引:5
本文对细胞凋亡和细胞坏死的发病机理和病理形态学进行了比较。凋亡是细胞的一种主动性死亡。其特点是单细胞发生,胞核浓缩、破裂,核碎块被胞膜包裹,形成特异性“凋亡小体”;细胞器多以萎缩变化为主。坏死则为细胞的被动性死亡,并常伴有炎症反应。作者认为:细胞凋亡和坏死虽然在发生机制和病理形态学方面有所区别,但它们的本质却是相同的,均为细胞的一种不可复性的退行性变化。 相似文献
104.
The right mammary gland of 12 lactating goats was inoculated intracisternally with 1 ml of Mycoplasma capricolum subsp. capripneumoniae (Mcc) containing 10>6 colony-forming units (CFU), while their left mammary halves received 1 ml of sterile PPLO broth only. Two goats served as uninfected controls. The clinical mastitis that developed in the infected mammary halves within 24 h was initially acute but became increasingly chronic by the end of the experiment at 24 days post inoculation (DPI). The disease was characterized by atrophy of the infected mammary halves, leading to marked agalactia and an increase in somatic cell counts, with a preponderance of neutrophils initially and lymphocytes later. The Mycoplasma was re-isolated from infected mammary secretions up to 16 DPI but not from blood. Histopathology revealed that the mastitis was acute and purulent initially, followed by infiltration of lymphonuclear cells and fibroplasia in the lymphomononuclear cells and fibroplasia in the interacinar tissue, and later by massive fibrosis. Immunohistology demonstrated the presence of Mycoplasma-like bodies localized mainly on the surface of acinar/duct epithelial cells. The studies showed that Mcc was highly pathogenic in the caprine mammary gland. 相似文献
105.
论述了平榛白粉病的发病规律,利用不同浓度的代森铵、多菌灵、甲基托布津、三唑酮和百菌清药剂对平榛白粉病进行防治试验,比较了不同种类和不同浓度的药剂对平榛白粉病的防治效果。结果表明:平榛白粉病初期发病为5月下旬至6月初,发病高峰期为6月下旬至7月下旬;代森铵、甲基托布津、多菌灵、百菌清、三唑酮等药剂对平榛白粉病的防治均有不同程度的效果,以25%三唑酮可湿性粉剂防治效果最好,可达到80%以上。 相似文献
106.
The pathogenesis of cyprinid herpesvirus‐3 (CyHV‐3) was studied using different lineages of carp/koi. After exposure to the virus, infected cells were first found in the skin by histopathology and by in situ hybridization. The epidermis of the skin was most severely damaged and often sloughed off in the fish sampled on days 5 through 8, and the fish that were highly sensitive to the virus died within 8 or 10 days after infection. Serum osmolality of the infected fish, particularly just before death, was significantly lower, suggesting that the osmotic shock consequent on the damage to the skin was the direct cause of the acute deaths. On the other hand, clinical and histopathological observations indicate that the carp of a less sensitive lineage most probably died of viral encephalitis around 3 weeks after infection. For these fish, the largest number of infected cells was found in the central nervous system (CNS) sampled on day 12. A substantial amount of viral genome was found in the CNS of carp surviving more than 1 year after the infection. Thus, the CNS is probably a major target for CyHV‐3, and the virus can persistently infect the CNS, presumably establishing latency. 相似文献
107.
竹丛枝病是竹类植物产生丛枝状病害的总称,是竹林退化最具破坏性的病害之一。大量研究表明:竹针孢座囊菌Aciculosporium take,异香柱菌属Heteroepichlo觕,竹暗球腔菌Phaeosphaeria bambusae以及植原体(phytoplas-ma)等均能引起竹丛枝病。长期以来这些病原物所处分类地位的变化较大且它们的致病机制尚不清楚,这对竹丛枝病的防治造成了极大的困难。对上述病原物所处分类地位的演变过程及其致病机制的研究进行了综述,并对竹丛枝病今后的研究方向进行了展望。参26 相似文献
108.
Infectious salmon anaemia (ISA) is a serious disease of farmed Atlantic salmon caused by the aquatic orthomyxovirus infectious salmon anaemia virus (ISAV). ISA was first detected in Norway in 1984 and was characterized by severe anaemia and circulatory disturbances. This review elucidates factors related to the pathogenesis of ISA in Atlantic salmon, the dissemination of the virus in the host and the general distribution of the 4‐O‐acetylated sialic acids ISAV receptor. The knowledge contributes to the understanding of this disease, and why, almost 30 years after the first detection, it is still causing problems for the aquaculture industry. 相似文献
109.
草莓褐色叶斑病是中国新发现的一种病害,造成叶片坏死和果实腐烂。为明确该病原菌的致病机理,对草莓褐色叶斑病菌产生的细胞壁降解酶进行研究。采用3,5-二硝基水杨酸法(DNS法)和紫外分光光度计法测定该病原菌产生的细胞壁降解酶的种类和活性。结果发现,该病原菌能够产生多种细胞壁降解酶,即多聚半乳糖醛酸酶(PG)、果胶甲基半乳糖醛酸酶(PMG)、多聚半乳糖醛酸反式消除酶(PGTE)和果胶甲基反式消除酶(PMTE),但不产生纤维素酶(Cx),其中PG和PMG活性较强,且PG和PMG在培养6天时活性最强,PMG在23℃条件下培养时活性最强,PG在28℃条件下培养时活性最强,静止和振荡交替培养有利于PG和PMG的产生。致病作用研究发现,果胶酶(PG和PMG)可引起果实腐烂和叶片坏死,说明其在该病原菌的致病过程中起重要作用。 相似文献
110.