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1.
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   

2.
婴幼儿从出生开始正常呼吸道微生物就无时不刻地进行着演替,最终呼吸系统微生物形成动态平衡。婴幼儿时期是呼吸道微生物群演替的重要时期,也是免疫发育的关键时期,容易受外界因素的影响,这些影响因素包括分娩方式、喂养方式、抗生素、季节、疫苗接种等。研究表明婴幼儿时期的呼吸道微生物的组成和发育会影响微生物群的稳定性,从而影响呼吸道感染和过敏性疾病的发生。现对婴幼儿呼吸道微生物群演替及其影响因素,如分娩方式、喂养方式、抗生素使用、季节、疫苗接种等进行综述。  相似文献   

3.
本文选择颊粘膜上皮细胞表面有微菌落形成的20例新生儿,取颊粘膜试子进行了较为细致的细菌培养、分离和鉴定,结果其中13例菌落生长很纯,均为α-溶血性菌落;另有3例α-溶血性菌株为绝对优势菌,二者共计16例,占80%(16/20)。其中LC.lactis.cremoris与Gemel-la在新生儿高定植率以及培养时菌落很纯显示对其它杂菌有较强的定植抗力等等,均提示它们是新生儿颊粘膜的有益定植菌,并很可能在新生儿呼吸系统的抗感染功能中发挥一定作用。  相似文献   

4.
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   

5.
本文调查了一周龄新生长的口咽部菌群,结果显示有约50%的5-7天龄的新生儿其咽部正常的甲型链球菌群未能建立,易于为致病性较强的菌株定植,这段时间是这部份新生儿的敏感“窗期”。表皮葡萄球菌也是在新生儿口咽部最早定值的“先驱菌”之一,但对新生儿似无保护作用,其致病作用表现得亦不明显。  相似文献   

6.
目的建立大气污染高血压(SHR/NCrl)大鼠动物模型,对染尘染毒前后SHR大鼠呼吸道微生态状况进行动态研究。了解染尘染毒前后其口咽部、呼吸道黏膜微生物菌群的动态变化,从而对大气污染引起的呼吸道感染提供科学依据。方法建立染尘染毒SHR大鼠模型,用无菌棉拭子进行咽拭取材后对菌群分离培养、纯化、革兰染色。结果在染尘染毒后SHR大鼠的需氧菌、厌氧菌及总细菌的菌群密度有上升趋势,其中需氧菌及总细菌的菌群密度与染尘染毒前相比有明显增高(P0.05)。结论暴露于大气污染物中使SHR大鼠口咽部细菌出现菌群失调,破坏了机体的微生态平衡。  相似文献   

7.
阴道微生态对围产期结局的影响已成为近期医学研究的焦点。阴道内定植有多种微生物,其中优势菌为乳杆菌,维持着阴道内正常pH。当机体免疫防御能力降低或者内分泌系统紊乱时,机会致病菌占据优势,极易诱发阴道炎性病变,严重影响妊娠期女性正常生活,并且对胎儿的发育及健康成长造成威胁,导致早产和胎膜早破等不良妊娠结局的发生。由于阴道菌群毒力强弱具有差异性,感染所致的阴道炎性疾病容易复发且不易根除,因此在治疗方面,临床医师需要根据个体化原则指导用药。本文对近年来阴道微生态与妊娠不良结局的相关性研究进行简要综述。  相似文献   

8.
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   

9.
目的 探讨微生态制剂对缺血性结肠炎大鼠肠道微生物和血脂的影响.方法 将30只SD大鼠制成缺血性结肠炎模型,并随机分为正常对照组、模型对照组和治疗组.正常对照组、模型对照组仅给予正常饲料喂食,治疗组在正常饲料喂食的基础上予复方嗜酸乳杆菌片灌胃(1×107 CFU/d),4周后抽血化验大鼠总胆固醇及甘油三酯,并处死大鼠,取肠道内容物做肠道乳酸菌、大肠埃希菌及真菌等微生物培养,数据采用统计学方法分析.结果 与正常对照组相比,模型对照组乳酸菌减少,差异有统计学意义(P<0.05),大肠埃希菌和真菌数量增加,差异有统计学意义(P<0.05);治疗组乳酸菌增多,差异有统计学意义(P<0.01),大肠埃希菌和真菌数量减少,差异有统计学意义(P<0.05).同时,治疗组大鼠总胆固醇及甘油三酯降低,差异有统计学意义(P<0.05).结论 缺血性结肠炎者出现肠道微生物紊乱,微生态制剂能增加肠道乳酸菌等益生菌,减少肠道条件致病菌和致病菌,维持肠道微生态平衡,同时对患者的血脂有一定的调节作用.  相似文献   

10.
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   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

13.
14.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

15.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

16.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

17.
Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l−1 glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l−1) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.  相似文献   

18.
The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.  相似文献   

19.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

20.
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