首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
消化道微生物区系与肥胖关系的研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
罗玉衡  朱伟云 《微生物学报》2007,47(6):1115-1118
肥胖以及与肥胖相关的一些疾病威胁着发达国家和发展中国家,这些疾病包括Ⅱ型糖尿病、高血压、心血管疾病、非酒精型脂肪肝。最新研究表明消化道微生物区系(microbiota,指一个特定区域中所有活的微生物群落的统称。)可能与宿主肥胖相关。目前此类研究尚处于起步阶段,作者总结了以往研究结果,对消化道微生物区系的组成和作用、与宿主能量代谢相关的消化道微生物种类和作用、消化道微生物区系影响宿主能量储存的途径作了较为详细的介绍。并探讨了目前研究中存在的问题,总结了本实验室已有研究成果,以及今后可能的研究方向。  相似文献   

2.
鸡肠道中寄生着数量庞大且复杂多样的微生物,对宿主的生长发育和健康十分重要,既影响着饲料消化、营养物质吸收,又参与了宿主肠道形态和免疫系统的调控。深入了解鸡肠道微生物区系的时空变化及早期定植特点,将有助于提出新的肠道微生态干预策略,应用于生产。就鸡肠道微生物组成和演替、早期微生物区系建立及调控等方面进行综述,并总结了一些最新研究进展。  相似文献   

3.
大曲酒微生物区系的初步研究   总被引:6,自引:0,他引:6  
李云英  李能树 《生物学杂志》1996,13(3):19-21,15
通过对四个酒厂发酵料的分离、培养,共获得霉菌56种;细菌34种;酵母菌21种;放线菌3种。确定了优势菌株。发现在大曲酒发酵过程中,微生物数量在不同发酵期里规律变化。  相似文献   

4.
目的研究口臭口腔微生物区系组成,为口臭治疗提供依据。方法采用稀释平板测数法对需氧和厌氧细菌、真菌、放线菌分别进行计数。结果非口臭口腔好氧细菌数量(1180±380)和厌氧细菌数量(680±100)分别低于口臭口腔好氧细菌数量(7200±800)和厌氧细菌数量(12520±120),差异有统计学意义(P0.01),且口臭口腔以革兰阳性菌和杆菌占优势,非口臭口腔真菌数量低于口臭口腔真菌数量,两者差异无统计学意义(P0.05)。口腔中没有检出放线菌。结论口臭患者口腔微生物多样性高于非口臭组,可以通过调整口腔微生态改善口臭。  相似文献   

5.
南极长城站微生物区系调查   总被引:8,自引:1,他引:7  
1992~1993年的夏季,对南极中国长城站的陆地进行了微生物区系的现场调查。先后采集各种类型上样多个。其中对有生态意义的25个样进行了不同类型微生物的分离和计数;中温培养下每克湿土壤菌量为102~106,用马丁培养基对真菌进行分离培养和计数,每克湿土含菌量为102~104;0℃下分离计数,发现低温下微生物的数量较中温的多,每克湿土壤含菌为103~106。对该地区烃氧化菌进行了特别调查,以长城站为中心东西宽0.4Km,南北长1Km的范围内烃氧化菌发育最为活跃,但距长城站距离越远,烃氧化菌数量越少。  相似文献   

6.
健康新生儿口腔微生物的早期定植研究   总被引:3,自引:0,他引:3  
目的:观察母亲阴道细菌对其新生儿口腔微生物定植的影响,确定早期定植于新生儿口腔的细菌种类以及新生儿口腔的优势菌,观察不同喂养方式对新生儿口腔微生物的影响。方法:对刚出生的22名健康新生儿口腔及其母亲分娩前的阴道进行棉拭子取样,新生儿连续一周每天口腔取样,在需氧、兼性厌氧、厌氧条件下培养,检出细菌经形态学及生化鉴定。刚出生婴儿的口腔拭子及其母亲阴道拭子选用成品的CY酵母菌业色检测培养盒检测酵母菌。结果:剖腹生产的刚出生的健康婴儿口腔100%无菌,经产道生产的刚出生的健康婴儿口腔25%有菌;母亲阴道细菌Staphlococcus epidermidis(S.epidermidis),Streptococcus faecalis (S.faecalis),Lactobacilli spp.在经产道生产的刚出生的新生儿口腔中可以检出;45.5%新生儿出生后第二天可检出Streptococcus salivarius (S.salivarius)的定植,S.salivarius和Streptococcus mitis(S.mitis)为出生一周新生儿口腔的优势菌;9.1%的新生儿口腔中可检出厌氧菌Veillinella spp.。母乳喂养和人工喂养的新生儿口腔优势菌差异无显著性(P>0.05),但人工喂养新生儿口腔中的S.epidermidis检出率和菌量均明显低于母乳喂养组(P>0.05)。结论:母亲阴道细菌对经产道生产的新生儿口腔微生物的定植有一定影响,出生一周的健康婴儿口腔中的优势菌为S.salivarius和S mitis,Veillonella spp.,是最早定植在新生儿口腔中的厌氧菌,不同喂养方式对优势菌在新生儿口腔的早期定植无明显影响。  相似文献   

7.
黄土高原不同植被坡地土壤微生物区系特征   总被引:21,自引:1,他引:21       下载免费PDF全文
应用稀释平板法对黄土高原不同植被覆盖下坡地土壤0~5cm和5~20cm土层的细菌、真菌和放线菌的分布特征进行了研究;结果表明:(1)该区域不同植被下土壤中细菌、真菌和放线菌总体比较丰富,数量差异较大,柠条土壤中微生物数量最多,苜蓿地中的最少.同一植被下各类菌群数量排序为细菌>放线菌>真菌.(2)放线菌和真菌随土层深度的增加而呈明显的减少趋势,而细菌的不明显.(3)天然荒坡的微生物数量高于人工草地的,人工灌木林微生物数量高于人工乔木林的,人工乔草复生果树林的微生物数量高于人工纯生乔木林、纯生草地和纯生果树林的.  相似文献   

8.
研究N-氨甲酰谷氨酸(NCG)对断奶仔猪肠道微生物区系的影响。试验选用体重为3.17±0.21 kg的21日龄断奶环江香猪12头,随机分为2组,每组6头,分别饲喂添加0.1%NCG日粮和基础日粮,试验期为14d。试验结束时,采集回肠和盲肠内容物,利用T-RFLP、PCR/DGGE和荧光定量PCR技术,测定其肠道微生物区系的变化。结果表明,与对照组相比,NCG组回肠内容物中微生物的多样性增加,回肠和盲肠内容物中双歧杆菌和乳酸杆菌的数量显著增加、大肠埃希菌的数量显著降低(P0.05),盲肠内容物中链球菌的数量也显著降低(P0.05)。可见,日粮中添加0.1%NCG有助于提高断奶环江香猪肠道内容物中有益菌的数量、抑制有害菌的繁殖,从而改善肠道微生物区系。  相似文献   

9.
Ce积累对黄褐土中土壤微生物区系的影响   总被引:11,自引:5,他引:11  
在黄褐土中模拟长期使用稀土微肥产生的Ce积累以研究稀土对土壤微生物的生态效应 .不同类群微生物对Ce的敏感性依序为细菌 >放线菌 >真菌 .1 0 %吸附容量以上的Ce对细菌总数都产生抑制作用 .1 0 %吸附容量以下的Ce对放线菌总数产生刺激作用 .5~ 50 %吸附容量的Ce对真菌总数产生刺激作用 .5%吸附容量以上的Ce对好气性纤维素分解细菌和氨化细菌都产生抑制作用 .5~ 1 0 %吸附容量和 5~ 50 %吸附容量的Ce分别对分解纤维素真菌、分解蛋白质的真菌产生刺激作用 .在高积累Ce的胁迫下放线菌、真菌、分解纤维素真菌和氨化微生物的种群结构发生了不同程度的改变 .  相似文献   

10.
不同种植年限菜田土壤微生物区系的研究   总被引:7,自引:0,他引:7  
采用稀释平板涂抹法对山东聊城周边地区不同种植年限的菜田土壤微生物数量、组成与养分状况及其相互关系进行了研究。结果表明:①该地区土壤微生物以细菌占绝对优势,其次为放线菌;②随着种菜年限的增加,土壤细菌和微生物总数表现出“低高低”的变化趋势,而真菌和放线菌则随种菜年限的增加而增加;③菜田土壤各类微生物主要集中在0~20cm的土层中,随着土层加深,其数量迅速减少;④菜田土壤放线菌组成复杂,共分离到了6个属的放线菌,但仍以链霉菌为主,其次为小单胞菌属和马杜拉放线菌属。链霉菌可分为9个类群,白孢类群占优势。种植1—2a的菜田土壤放线菌组成复杂,而链霉茼组成较简单;⑤蔬菜种类不同时,土壤微生物亦不同;⑥土壤养分含量与真菌和放线菌呈负相关,与细菌和微生物总数呈正相关。  相似文献   

11.
The effects of soil P amendments and time of application on the formation of external mycelium by different arbuscular mycorrhizal (AM) fungi were studied. In the first experiment the external mycelium produced in the soil by the AM fungus Glomus etunicatum Beck. and Gerd., during the early stages of root colonization (7 and 14 days after inoculation), was quantified by the soil-agar film technique. A Brazilian Oxisol was used with three different phosphate levels, varying from deficient to supra-optimal for the plant. Significant differences were observed in the phosphate and inoculation treatments for plant dry weight, P content in the tissue, root length and root colonization, at fourteen days after planting. At 7 days, mycelium growth, root colonization and their relationship were reduced at supra-optimal P concentrations. Applications of P one week after planting reduced mycelium growth and root colonization more than when applied to the soil before planting. In a second experiment the arbuscular mycorrhizal (AM) fungi, Scutellospora heterogama (Nicol. and Gerd.) Walker and Sanders and E3 were tested and compared with Glomus etunicatum. For the species studied, the length of external hyphae per unit of colonized root length was affected by small P additions but no further significant differences were observed at high P levels. The three AM endophytes showed marked differences in their response to P in the soil: Scutellospora heterogama, although producing external mycelium more profusely than the Glomus spp., showed a higher sensitivity to soil P supply.  相似文献   

12.
13.
The mammalian gut microbiota is essential in shaping many of its host''s functional attributes. One such microbiota resides in the bovine digestive tract in a compartment termed as the rumen. The rumen microbiota is necessary for the proper physiological development of the rumen and for the animal''s ability to digest and convert plant mass into food products, making it highly significant to humans. The establishment of this microbial population and the changes occurring with the host''s age are important for understanding this key microbial community. Despite its importance, little information about colonization of the microbial populations in newborn animals, and the gradual changes occurring thereafter, exists. Here, we characterized the overall bovine ruminal bacterial populations of five age groups, from 1-day-old calves to 2-year-old cows. We describe the changes occurring in the rumen ecosystem after birth, reflected by a decline in aerobic and facultative anaerobic taxa and an increase in anaerobic ones. Some rumen bacteria that are essential for mature rumen function could be detected as early as 1 day after birth, long before the rumen is active or even before ingestion of plant material occurs. The diversity and within-group similarity increased with age, suggesting a more diverse but homogeneous and specific mature community, compared with the more heterogeneous and less diverse primary community. In addition, a convergence toward a mature bacterial arrangement with age was observed. These findings have also been reported for human gut microbiota, suggesting that similar forces drive the establishment of gut microbiotas in these two distinct mammalian digestive systems.  相似文献   

14.
The role of gut microflora in ascorbic acid catabolism was investigated in both conventional and germ-free guinea pigs. In vitro studies demonstrated extensive degradation of the vitamin by fresh feces, cecal, and colonic contents of conventional guinea pigs. Direct injection of [1-14C] ascorbic acid into the cecum of conventional guinea pigs in vivo yielded a 70% recovery of the label as respiratory 14CO2 within 6 hr compared with only 5% recovery following injection into the virtually sterile peritoneum in a comparable group of conventional guinea pigs. Thus, ascorbic acid not absorbed prior to reaching the lower gastrointestinal tract stands to be extensively decarboxylated by microflora in the cecum. In a companion study of germ-free guinea pigs, 10% of an administered dose of [1-14C] ascorbic acid was expired as 14CO2 within 36 hr post-injection following intraperitoneal injection compared with 16% recovery in a matched group of conventional animals injected at the same site. Results of this series of studies suggest that hepatic decarboxylation and gut microflora, in tandem, contribute to ascorbic acid decarboxylation in this species.  相似文献   

15.
16.
在农村每月进行计划免疫时给新生儿接种乙型肝炎血源疫苗,剂量为10μg×3,程序为0、1、6个月,首剂免疫时间(以此为0月计算)平均在出生后1.5±1.2个月。全程接种率达92.9%。免疫儿童长到12~48月龄时HBsAg阳性率由原来的15.1%降至2.0%,保护率为86.8%。血清抗-HBs阳性率从免疫前地区本底对照的27.7%上升到87.3%,增加2.2倍。在免疫屏障的保护下,同龄未免儿童的HBsAg阳性率和HBV感染率分别下降到4.9%和16.0%,比免疫前地区本底对照低67.5%和70.4%。本研究结果表明,3针10μg乙肝疫苗于新生儿出生后1~3个月内接种仍能有效地降低HBsAg携带率,即使完全忽略了HBsAg阳性母亲的围产期传播。但必须达到很高的全程接种率。  相似文献   

17.
益生菌产生的细菌素及其功能机制   总被引:2,自引:0,他引:2       下载免费PDF全文
滕坤玲  钟瑾 《微生物学报》2022,62(3):858-868
细菌素是细菌核糖体合成的具有抑菌活性的小肽.细菌素的产生是益生菌重要的益生特性,它们天然无毒,不仅对食品腐败菌和人体致病菌有很好的抑菌活性,还具有有助益生菌定殖和调节肠道菌群等益生特性.本文综述了益生菌产生的细菌素的种类、条件性合成、益生功能及其作用机理等,以期为深入认识益生菌的益生功能及其作用方式,研究开发对人体有益...  相似文献   

18.
BACKGROUND: Acquisition of Helicobacter pylori infection occurs in early childhood, but the exact time of the acquisition and dynamics of infection are not clear. The aim of this study was to estimate the time of acquisition of H. pylori colonization in infants. SUBJECTS AND METHODS: This prospective follow-up study included 237 infants born in Wakayama Rosai Hospital from February, 2001 to April, 2002. Stool samples were collected at indicated ages, and H. pylori antigens were determined by a stool antigen test, HpSA. RESULTS: One-hundred and eight infants among initially enrolled 237 children have been followed up until 24 months. Among these, 16 infants turned to be HpSA positive within 12 months, but only four remained positive by the consecutive tests with optical density values of more than 0.7. They were assumed persistent positives. The rest 12 infants reverted to be negative by the consecutive tests and were assumed transient or false-positives. The optical density values of HpSA in the transient cases were exclusively less than 0.35. CONCLUSIONS: The consecutive follow up of HpSA, but not the one-point test, might be useful to diagnose persistent colonization of H. pylori in young infants, and some infants seemed to acquire H. pylori infection in the first year of life. These results should be taken into account for prevention and treatment strategies for H. pylori infection in infants.  相似文献   

19.
20.
    
The Chinese alligator (Alligator sinensis) is currently an endangered species due to a combination of factors, including climate change, anthropogenic activities, and habitat fragmentation. Captivity plays a crucial role in mitigating the decline of the Chinese alligator population. Currently, there is a lack of clarity regarding the influence of host development and captive conditions on the gut microbiota of Chinese alligators. The aim of the study was to investigate the gut bacterial communities of Chinese alligators and their surrounding environmental bacterial communities using 16S rRNA sequencing. The primary gut flora of Chinese alligators consists of Proteobacteria, Bacteroidetes, and Firmicutes. Proteobacteria is the most abundant and efficient settler in the gut, water, and sediment. PCoA and Adonis test revealed significant differences in bacterial communities across these habitats. Venn analysis revealed overlap in OTUs among the gut, water, and sediment, varying with growth stage and density stress. Different growth stages of Chinese alligator guts harbor distinct pathogenic bacteria, requiring attention. Density stress leads to an increase in pathogenic bacteria, a decrease in gut absorption efficiency. PICRUst2 predicts more abundant metabolic pathways related to gut function during high-density stress, possibly linked to Roseburia. SourceTracker Analysis indicated that water bacteria have a greater impact on Chinese alligator gut bacteria than sediment, and density stress significantly affects the contribution of environmental microorganisms to the gut microbes of Chinese alligator. BugBase analysis identified water body microbes as the main source of “potentially pathogenic” phenotypes in the gut microbiota. RDA analysis found dissolved oxygen (DO) in water to be the most significant factor influencing water microorganisms, positively correlated with certain pathogenic strains. These findings enhance our understanding of the significance of microbial communities in the gut and surrounding aquatic environment of the Chinese alligator. Furthermore, they provide theoretical support for environmental regulation, disease control, and healthy breeding.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号