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1.
目的探讨大气混合污染物对呼吸道微生态影响的机制,为预防大气污染对机体健康的损害提供理论依据。方法采用模拟实际大气污染方法,对Wistar大鼠进行染尘染毒,制备大气污染物动物模型,研究大鼠口咽部菌群染尘染毒前后的变化。结果染尘染毒的Wistar大鼠动物模型口咽部微生态发生改变(P<0.05)。染尘染毒后与染尘染毒前相比致病菌如中间葡萄球菌、猪链球菌、乙型链球菌等检出率明显增高(P<0.05)。染尘染毒前后自身比较,厌氧细菌菌群密度有明显增加(P<0.05),随着染尘染毒时间的延长,细菌的密度呈上下波动,表现出代偿状态。且需氧菌密度的变化较为明显(P<0.01)。结论大气污染可导致大鼠口咽部细菌密集度增高、致病菌增加以及细菌量的变化,呼吸道微生态改变可作为大气污染对机体危害的敏感指标。  相似文献   

2.
大气污染对大鼠呼吸道微生态的影响研究   总被引:2,自引:0,他引:2  
探讨了大气污染引起呼吸道症状和机体健康效应的作用机理,为防治大气污染及其对机体的损害提供理论依据。采用模拟现实大气污染的方法,分高、中、低浓度用Wistar大鼠制备大气污染动物模型,对大鼠口咽部菌群进行定性、定量、定位检测,动态研究。大气污染大鼠模型口咽部微生态发生改变。与污染前比,肺炎克雷伯杆菌等致病菌检出率明显增加(P<0.05),厌氧菌含量明显减少(P<0.05),并且随着染毒时间厌氧菌和细菌总量都呈明显下降趋势(P<0.05);口咽部菌群含量在一定范围内波动,没有随着染毒浓度改变而呈明显改变。大气污染对呼吸道正常菌群有毒害作用,对微环境有破坏作用,导致微环境改变,正常菌群含量减少,致病菌定植,是呼吸道疾病发病率升高的重要因素之一。  相似文献   

3.
探讨大气混合污染物对呼吸道影响的机理,为预防大气污染对人体健康的损害提供理论依据。采用模拟现实大气污染方法,用Wistar大鼠制备大气污染物动物模型,对大鼠口咽部菌群进行定位、定性、定量研究。大气污染Wistar大鼠动物模型口咽部微生态发生改变(P<0.05)。受污染后与污染前相比致病菌,如金黄色葡萄球菌、厌氧菌、死亡梭菌等检出率明显增高(P<0.05)。染尘染毒前后自身比较,厌氧细菌菌群密度有明显增加(P<0.05),随着染尘染毒时间的延长,细菌的密度呈上下波动,表现出代偿状态。且需氧菌密度的变化较为明显(P<0.05)。大气污染可导致大鼠口咽部细菌密集度增高、致病菌增加以及细菌量的变化,呼吸道微生态改变可作为大气污染对机体危害的敏感指标。  相似文献   

4.
大气污染对人体免疫功能及微生态的影响   总被引:5,自引:1,他引:5  
目的 :探讨大气污染对免疫功能及呼吸道菌群的影响 ,为改善生存环境 ,提高生存质量 ,预防呼吸道疾患提供科学依据。方法 :选择重污染区和轻污染区 ,以没有职业接触 ,近 3个月未用抗生素类药物的6~ 8岁儿童作为研究对象 ,用酶联免疫法检测血清免疫球蛋白含量 ;对其口咽部菌群进行定性、定量分析 ,进行对比研究。结果 :免疫球蛋白水平和口咽部菌群受外环境的影响较大 ,重污染区儿童 Ig A、Ig M水平低于轻污染区 ,Ig G、Ig E水平高于轻污染区 ,差异有显著性 (P<0 .0 1或 P<0 .0 5 ) ,重污染区儿童口咽部菌群密度明显高于轻污染区 (P<0 .0 1) ,且需氧菌与厌氧菌之比也明显增高 (P<0 .0 1) ,甲型链球菌检出率较低(P<0 .0 5 )。结论 :大气污染对免疫球蛋白水平和呼吸道菌群的定植具有明显的影响 ,是使免疫功能受到损害 ,微生态失调 ,呼吸道疾病感染率增高的重要因素。  相似文献   

5.
呼吸道感染是常见病多发病,而呼吸道感染可导致微生态失调。有报道,宿主的任何病理变化都可作为生态失调的微观环境因素。微观环境对正常微生物群的影响是直接的;而且是主要的。为此,我们对吸烟和被动吸烟者的微生态变化及呼吸道感染患者微生态的变化以及二者之间的关系进行了研究。以进一步探讨吸烟对呼吸道感染患者直接或间接的影响。研究结果表明,吸烟及被动吸烟者患反复呼吸道感染的年发生率明显高于不吸烟者。健康对照组与患者口咽部菌群数相比有显著差异,无论是吸烟还是不吸烟的患者菌群含量均高于健康对照组(P<005)。结果表明,吸烟不仅有害于自身健康,而且危害被动吸烟者,其对呼吸道微生态的影响都是一致的,即可导致微生态失调,从而导致呼吸道疾病  相似文献   

6.
降胆固醇微生态制剂对大鼠高血脂的影响   总被引:7,自引:0,他引:7  
应用从鱼体内自行分离的一株细菌,以高脂大白鼠为实验模型,研究投喂不同浓度的该活菌制剂(5×10  相似文献   

7.
目的探讨被动吸烟对呼吸道微生态的影响的机制,为预防吸烟对机体健康的损害提供理论依据。方法采用模拟被动吸烟的方法,对健康Wistar大鼠进行大气污染,研究大鼠口咽部菌群污染前后的变化。结果被动吸烟前后大鼠口咽部的微生态菌群明显发生改变(P〈0.5)。吸烟前与吸烟后相比致病菌如金黄色葡萄球菌、肺炎克雷伯菌等检出率明显增高(P〈0.5),厌氧菌密度减少,随着被动吸烟时间的延长,细菌的密度呈上下波动,且厌氧菌菌群密度变化更为明显(P〈0.5)。结论被动吸烟对大鼠口咽部有破坏作用,导致菌群发生改变,致病菌增多,是呼吸道疾病发病率升高的重要因素之一。  相似文献   

8.
低聚木糖对模拟失重大鼠肠道微生态的影响   总被引:3,自引:0,他引:3  
目的 研究低聚木糖对模拟失重大鼠肠道微生态的影响。方法 采用大鼠尾部悬吊法模拟失重。32只雄性SD大鼠随机分为4组,每组8只:FC组(地面对照组,饲喂基础饲料),FS组(地面处理组,饲喂添加低聚木糖的饲料),SC组(尾吊对照组,饲喂基础饲料)。SS组(尾吊处理组,饲喂添加低聚木糖的饲料),实验21d,SC和SS组解除尾吊继续观察。实验21d。采用选择性培养基对大鼠粪便肠杆菌、肠球菌、类杆菌、双歧杆菌以及乳杆菌进行定量测定。结果 SC组与FC组相比,双歧杆菌数量减少,肠杆菌和肠球菌数量增加;FS组比FC组双歧杆菌数量增加显著,肠杆菌和肠球菌有不同程度的减少,SS组比SC组双歧杆菌数量增加显著,肠杆菌和肠球菌也有不同程度的减少。类杆菌和乳杆菌变化不明显。尾吊解除期,SS组双歧杆菌数量比SC组更快恢复到正常水平。结论 低聚木糖可促进尾吊大鼠肠道益生菌主要是双歧杆菌的增殖,一定程度上促进由于模拟失重造成肠道微生态失调的平衡,并对条件致病菌具有一定的抑制作用。  相似文献   

9.
目的 通过研究健康老年机体上呼吸道微生态菌群构成,了解老龄人群上呼吸道优势菌群种类及数量,为从微生态学角度预防呼吸道感染的发生提供参考。方法 自沈阳市选取年龄为65~70岁健康老人为研究对象,无菌咽拭法采集咽后壁粘膜表面标本,对菌群进行定量分析、定性鉴定。结果 老年人群咽后壁需氧菌群与厌氧菌群数量之比为2.65∶1,检出率较高的需氧菌及厌氧菌包括唾液链球菌、口腔链球菌、缓症链球菌、微黄奈瑟菌、灰色奈瑟菌、麻疹孪生球菌等,检出率较高的菌构成比也较高。结论 健康老年人群中检出率和构成比都较高的需氧菌和厌氧菌共同构成老年人上呼吸道口咽部优势菌群,在维持呼吸系统微生态平衡中起重要作用,可作为上呼吸道微生态学研究的重要指标菌。  相似文献   

10.
模拟失重对大鼠肠道菌群影响的研究   总被引:8,自引:2,他引:6  
目的:研究模拟失重条件下大鼠肠道菌群变化情况。方法:选择性培养基分别对肠球菌、肠杆菌、类杆菌、乳杆菌以及双歧杆菌进行定量测定,扫描电镜观察大鼠盲肠上皮细胞的组织变化。结果:过路菌群中肠杆菌和肠球菌数量增加显著;原籍菌群中双歧杆菌减少十分明显,乳杆菌的数量也有不同程度的减少,而类杆菌的数量有增加的趋势。SD大鼠盲肠出现了肿胀细胞,上皮细胞颈毛排列紊乱、稀疏。结论:模拟失重条件下大鼠肠道微生态出现平衡失调。  相似文献   

11.
Historic limestone materials in urban environments are continually exposed to air pollutants, including sulfur compounds and hydrocarbons. We investigated the effects of air pollution on the biofilm microflora of historic limestone gravestones located at two locations Massachusetts, USA. Our data showed that the culturable populations of chemolithotrophic and heterotrophic bacteria, and fungi were suppressed in the polluted habitat comparing with the unpolluted location. The diversity of the microflora was also reduced in the surface biofilms on gravestones in the city contaminated by air pollution. However, both the sulfur-oxidizing and hydrocarbon-utilizing microflora were enriched in the biofilms exposed to air pollution. In a laboratory study, low concentrations of the polluting chemicals stimulated growth of these bacteria, and resulted in rapid acid production. Scanning electron microscopy demonstrated that the biofilms of both the sulfur-oxidizing bacteria and the hydrocarbon-degrading microflora penetrated into the limestone. The enrichment of sulfur- and hydrocarbon-utilizing bacteria in the biofilms may contribute to dissolution of the stone. However, further research is required to determine the effects of specific metabolites of these microorganisms on stone deterioration.  相似文献   

12.
目的探究吸烟对人体内的呼吸道微生态的影响。方法采用细菌鉴定及药敏分析系统鉴定健康吸烟者与非吸烟者,患下呼吸道感染吸烟与非吸烟者咽后壁分泌物的细菌密度、细菌数量及种类的改变。结果在健康吸烟者与患有下呼吸道感染患者的呼吸道中,厌氧菌明显升高,其中以韦荣菌和消化链球菌为主。结论吸烟可使人体的呼吸道微生态中细菌密度,细菌数量及种类的改变,易患呼吸系统疾病。  相似文献   

13.
14.
Material obtained from the mucous membranes of the upper respiratory tract (the anterior section of the nasal cavity, the fauces) in young children, both healthy and suffering with different forms of acute pneumonia, has been analyzed with due regard to the structure of the microflora, its specific composition and the size of populations formed by different species constituting the microflora. This analysis has made it possible to determine the species constituting normal microflora, to detect its dysbiotic changes, and to determine their degree (partial or complete dysbacteriosis). The degree of pathologic changes in the microecological balance of the upper respiratory tract has been shown to reflect the severity of acute pneumonia and to be determined by the characteristics of the natural resistance system in young children.  相似文献   

15.
Studies have been carried out on specimens of Saltrio stone, Carrara and Candoglia marbles, exposed for some years to the polluted atmosphere of Milan. The test specimens, which were directly exposed to the washing away, showed alterations in the form of grey-black stains which were different in dimensions and quantity according to the stone material, while those sheltered showed only a uniform grey deposit of particulate matter. The decay on the exposed specimens has been tested by gravimetric analyses and scanning electron microscopy (SEM) observations. Microbiological investigations evidenced that microorganisms, either chemoautotrophic or photosynthetic, were not present in any sample. On the washed out test specimens, the presence of heterotrophic bacteria was considerable, while the sheltered specimens showed negligible values. Chemical analysis, carried out through gas chromatography–mass spectrometry (GC/MS), of the particulate deposited on the test specimens, evidenced the presence of a wide range of aromatic and aliphatic hydrocarbons and fatty acids. Cultural tests of mixed cultures and isolated strains were carried out by using a mineral medium added with 14 organic compounds, typical representatives of atmospheric pollution, as a sole source of carbon and energy. The results evidenced that the mixed cultures in particular, as well as some of the isolated strains, are capable of using many of the tested molecules (fatty acid, aliphatic compounds, p-xylene).  相似文献   

16.
Upper respiratory tract consists resident and transient bacterial microflora, which in appropriate condition can cause infection. Bacteriological study was performed among 201 patients with upper respiratory tract infections treated in ambulatory. From nasal and pharyngeal swabs Staphylococcus aureus, Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and Streptococci group A, B, C, G were isolated. Antibiotic susceptibility testing of isolated strains was performed using CLSI criteria. All isolated strains of streptococci were susceptible to penicillin; some of them demonstrated resistance to macrolides and lincosamides. Few isolated strains of H. influenzae demonstrated resistance to penicillin and cotrimoxazole. Azitromycin resistant strains were not detected. All isolated strains of M. catarrhalis were beta-lactamase positive and demonstrated resistance to penicillin. Strains of methicillin sensitive S. aureus (MSSA) were isolated most frequently from pharyngeal swabs (35.4%) and S. pneumoniae (33.3)--from nasal swabs.  相似文献   

17.

Background

Recent studies break with traditional opinion that the lower respiratory tract is sterile, and increasingly focus on the lung microbiome and disease. Smoking, as an important etiology of inflammatory lung disease, was considered as a factor influencing lung microbiome variations in our study, and we aimed to study the effect of smoking on inflammation and microbial diversity and community.

Methods

Forty male mice were selected and randomly divided into a smoking and a non-smoking group. Mice in the smoking group were exposed to smoke smog for 2?h/day for 90?days. Blood and lung tissues were obtained after the experiment, and ELISA was used to measure interleukin-6 and C reactive protein concentrations. 16S rRNA gene quantification and sequencing technology were used to compare microbial diversity and community between the two groups. SAS 9.1 and R software were used to analyze the data.

Results

Thirty-six mice survived, and the weight of the smoking group increased more slowly than that of the non-smoking group. Denser inflammation and congestion were observed in the lungs of the smoking mice compared with the non-smoking group Higher microbial diversity was observed in the smoking group, and Enterobacter, Acidimicrobiales_norank, and Caulobacteraceae_Unclassified genus were significantly more abundant in the non-smoking group (P?<?0.001).

Conclusions

Smoking altered microbial diversities and communities in the lower respiratory tract of mice. Microbial variation should be considered in future studies focusing on smoking-induced inflammatory disease.
  相似文献   

18.
The microflora of the female reproductive tract is very diverse and plays an important role in both normal and pathological states. The data on the mechanisms of colonization resistance which involve the vaginal microbios (the production of H2O2, organic acids, bacteriocin-like substances, competition for adhesion sites) are presented. The data on the role of individual antagonistically active substances of anaerobic bacteria in suppressing gonococci, fungi, microorganisms, associated with bacterial vaginosis, etc. are given. The leading role of anaerobic microorganisms in the appearance of microecological disturbances, including bacterial vaginosis, is emphasized. The role of the pathogenic properties of anaerobic bacteria for the development of different pathological processes, such as premature birth, postnatal and postoperative purulent septic diseases, inflammation of pelvic organs, cancer of the neck of uterus, is discussed.  相似文献   

19.
目的 探究细菌性肺炎患儿实行闭环式护理管理模式后患儿临床症状、呼吸道菌群及疾病复发的情况。方法 选取2016年5月至2018年11月我院收治的113例细菌性肺炎患儿为研究对象,随机分为观察组(n=55)和对照组(n=58)。两组患儿均给予抗生素治疗及常规护理。观察组患儿在常规护理基础上应用闭环式护理。观察两组患儿各主要临床症状缓解时间及住院时间、治疗有效率、治疗前及治疗1周后呼吸道菌群分布情况及治疗结束后6个月内细菌性肺炎复发率。结果 观察组患儿体温恢复时间、咳嗽及咳痰缓解时间及住院时间均短于对照组(均P0.05)。观察组患儿治疗有效率为89.09%(49/55),高于对照组的72.41%(42/58)。结论 细菌性肺炎患儿呼吸道菌群以肺炎链球菌、金黄色葡萄球菌、肺炎克雷伯菌及大肠埃希菌为主。应用闭环式护理管理模式后,可明显改善细菌性肺炎患儿各临床症状,缩短症状缓解时间,抑制呼吸道革兰阳性菌群生长,但对治疗后复发率影响不大。  相似文献   

20.
Proteolytic cleavage activation of influenza virus hemagglutinin (HA0) is required for cell entry via receptor-mediated endocytosis. Despite numerous studies describing bacterial protease-mediated influenza A viral activation in mammals, very little is known about the role of intestinal bacterial flora of birds in hemagglutinin cleavage/activation. Therefore, the cloaca of wild waterfowl was examined for (i) representative bacterial types and (ii) their ability to cleave in a "trypsin-like" manner the precursor viral hemagglutinin molecule (HA0). Using radiolabeled HA0, bacterial secretion-mediated trypsin-like conversion of HA0 to HA1 and HA2 peptide products was observed to various degrees in 42 of 44 bacterial isolates suggestive of influenza virus activation in the cloaca of wild waterfowl. However, treatment of uncleaved virus with all bacterial isolates gave rise to substantially reduced emergent virus progeny compared with what was expected. Examination of two isolates exhibiting pronounced trypsin-like conversion of HA0 to HA1 and HA2 peptide products and low infectivity revealed lipase activity to be present. Because influenza virus possesses a complex lipid envelope, the presence of lipid hydrolase activity could in part account for the observed less-than-expected level of viable progeny. A thorough characterization of respective isolate protease HA0 hydrolysis products as well as other resident activities (i.e., lipase) is ongoing such that the role of these respective contributors in virus activation/inactivation can be firmly established.  相似文献   

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