琦琦 發問時間: 社會與文化語言 · 2 0 年前

徵求英文高手!有PCR及微生物概念的人!!(20點)

The genus Shigella is composed of Gram-negative facultative anaerobes of four species: Shigella dysenteriae, S. boydii, S. sonnei and S. flexneri. All are pathogens of humans and are usually transmitted from person to person as well as by ingestion of contaminated water and foods. The infective dose is very low, varying from 101 to 104 organisms (Rowe and Gross, 1984). Virulent Shigella organisms cause the human illness known as bacillary dysentery, as do enteroinvasive Escherichia coli (EIEC) strains. Clinical features of bacillary dysentery (shigellosis) include diarrhoea, fever, dysentery, and even death in some cases if effective intervention strategies are not used. Epidemiological studies of shigellosis in Bangladesh have shown that various water sources, e.g. ponds, lakes, wells, and rivers, can act as sources of infection (Islam et al., 1993a). In the United States, outbreaks of shigellosis have also been attributed to swimming in contaminated water ( Rosenberg et al., 1976). In South Africa, children under 5 yr of age living in settlements with rudimentary access to water supply and sanitation are the most susceptible to diarrhoea whereas adults often become symptomless carriers (Pergram et al., 1998). The difficulty in detecting carriers by culture techniques makes them a potential source of environmental contamination.

All of the virulent Shigella spp. and EIEC strains harbor a 120- to 230-kb plasmid named the virulence plasmid, which was first described for S. flexneri 2a. It was established that the invasion plasmid antigen gene (ipaH), unique to shigellae and EIEC and implicated in virulent functions, is present in multiple copies on the invasion plasmid and the chromosome (Venkatesan and Venkatesan; Hartman et al., 1990; Hale, 1991).

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    2 0 年前
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    The genus Shigella is composed of Gram-negative....

    志賀氏桿菌屬含有四種格蘭氏陰性兼性厭氧菌:赤痢志賀氏桿菌......

    All are pathogens of humans and are usually transmitted....

    這四種菌對人類皆有病原性,通常藉由食入受污染的食物或飲水在人與人之間傳播。

    The infective dose....

    感染量很低,只要101至104個菌體就能是感染成立。

    Virulent Shigella organisms cause the human illness....

    具毒力的志賀氏桿菌能如腸道入侵型大腸桿菌(EIEC)一般,導致人類的細菌性赤痢。

    Clinical features of bacillary dysentery (shigellosis) include....

    細菌性赤痢(志賀氏桿菌病)的臨床特徵包括下痢、發燒、赤痢,若無有效的醫療介入甚至可能造成死亡。

    Epidemiological studies of shigellosis in Bangladesh have shown that....

    在孟加拉的流行病學研究顯示池塘、湖泊、水井、河川等不同水源都可能是感染源。

    In the United States, ....

    美國也曾發生過因在污染水域內游泳而引起的志賀氏桿菌病疫情。

    In South Africa, ....

    南非五歲以下、生活在飲水衛生不良地區的孩童最易發生下痢,而成人通常成為無症狀的帶原者。

    The difficulty in detecting carriers by culture techniques ....

    由於藉由細菌培養不易檢出帶原者,使得帶原者容易成為環境的潛在污染源。

    All of the virulent Shigella spp. and EIEC strains....

    所有有毒力的志賀氏桿菌與EIEC皆帶有毒力質體,大小為120至230kb。此一現象首次在S. flexneri 2a這種志賀氏桿菌被提及。

    It was established that....

    入侵質體抗原基因(ipaH)為志賀氏桿菌與EIEC特有的基因,與這些細菌的毒力功能有關。以一基因以多個相同基因的型態存在於細菌的入侵質體及染色體內。

    參考資料: (沒有用到PCR技術呀)
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