共查询到20条相似文献，搜索用时 375 毫秒
1.
水中存在大量的致病性微生物,严重威胁人类和动物的健康。目前检测病原菌通常采用培养基培养法。但在不良环境下,一些病原菌能够进入“活的非可培养状态”（VBNC）,采用培养基培养方法可能无法检测出。文章介绍几种能够进入VBNC状态的水生病原菌和VBNC病原菌检测方法,为建立敏感特异的检测方法奠定基础。 相似文献
2.
活的非可培养状态(VBNC)细菌是一类利用现行培养技术无法分离得到的微生物群,对传统微生物学产生了重要影响。特别是一些处于VBNC状态下的病原菌,一直是最令人担忧且不可忽视的研究对象。论文从种类、形态、排列、组成、致病性、抗原性、黏附性,以及复苏等方面综述了VBNC细菌的生物学特性,旨在更加深入了解和认识VBNC细菌,从而对VBNC病原菌的防控起到积极作用。 相似文献
3.
"活的非可培养状态"(VBNC)细菌是一类具有新陈代谢活性和毒性,但是用常规培养方法(平板法和最大近似值法)检测不出来的一种特殊存在形式,是细菌抵抗恶劣生存环境的一种自我保护状态。该状态自从20世纪80年代被发现以来,受到微生物学界的极大关注,这不仅为环境中微生物多样性的发展提供了新的线索,而且对预防兽医学,疫病流行病学及公共卫生学等方面具有重要的意义。随着人们对细菌VBNC状态研究的不断深入,至今已发现至少20个种属的60多种细菌存在VBNC状态[1,2],大多数病原性细菌在进入VBNC状态后仍然保留其毒力,并且发现除了寡营养、高/低温、高压、pH或盐度的剧烈变化外,越来越多的因素如生存环境的改变;常规的消毒灭菌;生物因素等均可导致细菌进入VBNC状态。可复苏是VBNC细菌的一个重要特性,但是使VBNC状态的细菌恢复可培养状态的条件也存在着多样性和不确定性[3～5]。因此本文将对VBNC状态细菌的复苏方法进行综述。 相似文献
4.
自1982年细菌活的非可培养状态(Viable but nonculturable,VBNC)发现以来,人们就已逐渐明确和认识到由这些无法培养但却仍然存活的非可培养微生物所导致的公共卫生危害[1-2].细菌VBNC独特的生物学特征已经让人们意识到,在仍以培养技术为主要检出手段的情况下,一旦病原菌进入VBNC状态,便可保留毒力和致病性,极易成为逃避监测的隐性传染源,而造成漏检[3-4].目前,细菌VBNC状态形成机制尚不完全清楚,对其形成机理研究(即揭示环境因素对基因表达的调控机制)和实际(检测VBNC病原)意义已逐渐受到关注并成为研究的热点. 相似文献
5.
VBNC（Viable but nonculturable）是指非可培养微生物状态,徐怀恕等人在1982年通过对霍乱弧菌和大肠杆菌存活规律的研究,首次发现并提出了细菌“活的非可培养状态（Viable but non—culturable state,VBNC）,即细菌在不良环境条件下细胞缩成球形,用常规方法（平板法、最大可能近似值法）培养不能生长繁殖,但仍然具有代谢活性,是活的一种特殊的存在形式。 相似文献
6.
利用LIVE/DEAD试剂盒染色法,流式细胞仪检测法,以及RT-PCR方法检测了经低浓度冰醋酸作用的鸡源大肠杆菌活细胞,并对其进行了复苏。结果表明,当可培养菌数降为零时,LIVE/DEAD试剂盒染色法及流式细胞仪检测法均能检测出较高数量的活菌数;RT-PCR法也能检测到活细胞信号分子-mRNA,并扩增出“活的非可培养状态”（VBNC）细菌的cDNA片段。这些均显示细菌已进入VBNC,且在吐温80作用下又恢复为可培养状态,从而证实大肠杆菌具有“VBNC”状态。 相似文献
7.
细菌活的非可培养状态(VBNC),是细菌在不良环境中,失去生长繁殖能力,但仍旧存活的一种特殊存在形式。当食源性细菌进入这一状态后,无法用依照培养技术所建立起来的各种检测方法进行检验。针对此种情况,本文着重提出了两点解决策略即RT-PCR法和种群基因检测法,并对目前国内外建立VBNC细菌检测标准等问题向我国检疫与质量监督部门提出了建议。 相似文献
8.
以细菌活的非可培养状态(VBNC)领域中常用的SYTO-9和PI替代吖啶橙和萘啶酮酸,以市售的黑色钢笔墨水替代伊拉克黑,自行建立了一套VBNC细菌荧光显微镜检测方法,以期简化现行技术的操作流程,克服现有技术的适用范围狭窄、取材困难、观察结果不准确等缺点,旨在解决细菌VBNC研究领域中的技术难题,提高同业者的实践操作水平。 相似文献
9.
为了研究VBNC状态沙门菌特异性基因,探讨细菌VBNC状态发生机制,试验应用cDNA代表性差异分析技术(cDNA-RDA)对VBNC状态沙门菌特异性基因进行筛选及分析。结果表明:经过3轮差减杂交后,获得8条差异基因片段;分析差异基因功能,推测其中5条差异基因可能与沙门菌VBNC状态发生机制以及合成蛋白相关。 相似文献
10.
在基因分离与克隆中,构建各种cDNA文库是近些年发现新基因及研究基因功能常用的基础工具之一。其中,抑制性消减杂交技术(SSH)是一种高效分离差异表达基因的方法,在分离筛选细菌活的非可培养状态(VBNC)与正常菌株差异基因中,应用这种研究方法是研究细菌VBNC状态菌株毒力、致病性和耐药性及菌株遗传分化关系的重要途径。文章旨在介绍SSH构建消减cDNA文库在原核生物中的应用及对其在细菌VBNC状态新基因筛选中的应用前景,并提出了展望。 相似文献
12.
Ovine scrapie was first recorded in Cyprus in 1985. Subsequently four dairy goats kept in two mixed flocks with affected sheep developed characteristic clinical signs similar to those seen in sheep. Fifteen goats from the two flocks were examined histologically and neurological lesions consistent with a diagnosis of scrapie were found in the four animals and in three others which had subsequently developed early neurological signs. These lesions were similar to those of naturally-affected sheep although neuronal degeneration and vacuolation were more severe in some cases. 相似文献
13.
In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection. 相似文献
15.
In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario. Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously. 相似文献
17.
In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium. 相似文献
18.
In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%). Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada. 相似文献
19.
In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%). 相似文献
20.
In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated. Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively. 相似文献
|
