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1.
目的:研究低聚异麦芽糖对模拟失重大鼠肠道益生菌的影响以及与骨钙代谢变化的关系。方法:30只雄性SD大鼠随机分为3组(每组10只)FC组;普通对照组(饲喂普通饲料);SC组,模拟失重对照组(饲喂普通饲料);SS组,模拟失重低聚异麦芽糖组(饲喂普通饲料 低聚异麦芽糖),实验期21d。结果:SC组大鼠肠道益生菌(主要是双歧杆菌和乳杆菌)数量、饲料钙的表观吸收率、股骨骨密度(BMD),骨钙含量以及骨钙素(BGP)的水平显著低于FC组,而血钙水平明显高于FC组;SS组大鼠肠道益生菌数量,饲料钙的表观吸收率,骨密度,骨钙含量以及骨钙素水平较SC组高,血钙水平显著低于SC组。结论:低聚异麦芽糖可以促进模拟失重大鼠肠道益生菌的增殖,减少股骨骨质的丢失,提高股骨BMD,增加骨形成,对骨代谢产生一定的有益影响。  相似文献   

2.
目的:研究模拟失重条件下,施普瑞螺旋藻对大鼠肠道微生态失调的调整作用。方法:将基础饲料中加入5%的螺旋藻作为处理组饲喂大鼠,用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:螺旋藻处理组过路菌群中肠杆菌和肠球菌数量变化并不明显;原籍菌群中双歧杆菌较对照组显著增多,类杆菌和乳杆菌的数量差异没有显著性,模拟失重条件下SD大鼠盲肠上皮有肿胀细胞出现,并且肠道上皮绒毛排列紊乱、稀疏、而螺旋藻处理组中只发现有少量的肿胀细胞,上皮绒毛致密,排列较整齐。结论:旋普瑞螺旋藻具有纠正在模拟失重条件下大鼠肠道微生态平衡失调的作用。  相似文献   

3.
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   

4.
饮用加银水对模拟失重大鼠肠道微生态及骨钙代谢的影响   总被引:2,自引:0,他引:2  
目的 :研究饮用加银水对模拟失重大鼠肠道微生态及骨钙代谢的影响。方法 :30只 SD雄性大鼠随机分为地面对照组 ( GC)、模拟失重对照组 ( SC)和模拟失重饮用 0 .2 0 mg/ L 加银水组 ( SS) ,实验期 2 1d。第 7、14和 2 1天用选择性培养基分别对肠球菌、肠杆菌、双歧杆菌、乳杆菌及类杆菌定量测定 ,并测定饲料钙表观吸收率 ;第 2 1天取右侧股骨测骨密度和骨钙含量。结果 :骨密度和骨钙含量 SC组显著低于 GC组 ,SS组也低于 SC组 ;SC组和 GC组比较 ,SC组出现厌氧菌群的减少和需氧菌群的增加及饲料钙表观吸收率的下降 ,且这种变化出现较早 ,SS组和 SC组比较 ,SS组出现以厌氧菌群中 G 菌的减少和需氧菌群G-菌的增加为主的菌群失调及饲料钙表观吸收率的下降 ,且这种变化出现较晚。结论 :饮用 0 .2 0 mg/ L 加银水可以加重模拟失重大鼠肠道微生态的失调和骨钙代谢的紊乱 ,但需要较长的作用时间 ,且其微生态的失调以 G 细菌减少为主的厌氧菌群减少型  相似文献   

5.
赵娟  王晓蓉 《中国微生态学杂志》2021,33(11):1326-1329, 1339
目的分析肠道菌群与IBS分型及患者血清细胞间黏附分子 1(ICAM 1)表达的关系,为后续研究提供参考。方法选择2018年12月至2020年1月我院收治的152例符合标准的肠易激综合征(IBS)患者作为观察组,并依照罗马Ⅲ标准将观察组患者分为腹泻型组(62例)、便秘型组(56例)、混合型组(34例);选择同期我院健康体检者30例为对照组。检测受试者粪便中双歧杆菌、乳杆菌、肠杆菌和肠球菌数量,同时检测受试者血清ICAM 1水平。采用Pearson相关性分析患者肠道菌群与血清ICAM 1关系,并采用Logistics回归模型分析肠道菌群与IBS各亚型的关系。结果观察组患者血清ICAM 1、肠道双歧杆菌、乳杆菌水平显著低于对照组,肠道肠杆菌和肠球菌水平显著高于对照组,差异均有统计学意义(均P<0.05)。不同亚型IBS患者血清ICAM 1、肠道双歧杆菌、乳杆菌、肠杆菌和肠球菌水平存在明显差异,其中混合组患者血清ICAM 1、肠杆菌、肠球菌数量最高,双歧杆菌、乳杆菌数量最低;腹泻型组肠道肠杆菌、肠球菌数量最低,双歧杆菌、乳杆菌数量最高(均P<0.05)。肠道中双歧杆菌、乳杆菌、肠杆菌、肠球菌数量是IBS分型的独立影响因素(均P<0.05)。患者肠道双歧杆菌、乳杆菌数量与ICAM 1水平呈显著负相关,而肠道肠杆菌和肠球菌数量与ICAM 1水平呈显著正相关(均P<0.05)。结论肠道菌群可影响IBS患者分型,且肠道中部分菌群与ICAM 1水平存在显著相关关系。  相似文献   

6.
目的 探讨一种活性乳酸菌饮料对人体肠道菌群的影响作用.方法 采用卫生部《保健食品检验与评价技术规范》调节肠道菌群功能检验方法进行检验.结果 试食组试验前后自身比较:肠道内双歧杆菌、乳杆菌数量明显增加(P<0.01),肠球菌数量增加(P<0.05),产气荚膜梭菌数量明显减少(P<0.01),肠杆菌和拟杆菌无明显变化;试验后对照组与试食组组间比较:双歧杆菌数量明显增加(P<0.01),乳杆菌的数量增加(P<0.05),肠杆菌、肠球菌、产气荚膜梭菌和拟杆菌无明显变化.结论 活性乳酸菌饮料具有调节人体肠道菌群、改善肠道内环境的作用.  相似文献   

7.
几种益生元制剂对肠道菌群作用效果的研究   总被引:8,自引:0,他引:8  
目的探讨几种益生元制剂对肠道菌群作用效果。方法通过体外实验和体内试验。结果低聚果糖、水苏糖、低聚木糖、低聚异麦芽糖均能促进双歧杆菌和乳杆菌的增殖,并能够酸化肠道的pH;能够显著提高肠道的B/E值(肠道内双歧杆菌和肠杆菌数量log值的比值),增加肠道中有益菌的比例,有益于稳定肠道的微生态平衡。结论这几种益生元制剂对肠道菌群有较好的调节作用。  相似文献   

8.
目的通过观察青春双歧杆菌对2型糖尿病模型大鼠肠道菌群的变化,和血清中总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-C)、超氧化物歧化酶(SOD)和丙二醛(MDA)的水平,探讨青春双歧杆菌对2型糖尿病模型大鼠肠道功能和脂质代谢的影响。方法采用青春双歧杆菌灌胃2型糖尿病模型大鼠,取粪便检查正常菌群,取血和脏器检测TC、TG、HDL-C、SOD和MDA含量。结果青春双歧杆菌导致肠道内双歧杆菌、乳杆菌的数量增加,而肠杆菌、肠球菌数量下降;TC、TG和MDA水平下降,而HDL-C和SOD水平升高。结论青春双歧杆菌具有改善2型糖尿病模型大鼠肠道功能和降血脂作用,与二甲双胍联合应用效果更佳。  相似文献   

9.
目的 观察华支睾吸虫感染对大鼠肠道菌群的影响.方法 建立华支睾吸虫感染大鼠模型,分别在造模后48 h、18d和35 d,取肠内容物进行乳酸杆菌、双歧杆菌、肠球菌和肠杆菌的培养及定量分析.结果 与对照组相比,在感染后48 h,大鼠肠道乳酸杆菌和双歧杆菌数量减少(P<0.05),肠球菌和肠杆菌数量略有增加,但差异无统计学意义(P>0.05);在感染后18 d(童虫期),乳酸杆菌、双歧杆菌数量进一步减少(P<0.01),肠杆菌和肠球菌数量明显增加(P<0.01);在感染后35 d(成虫期),四种肠道菌与童虫期的变化基本一致.结论 华支睾吸虫感染可致大鼠肠道菌群发生失调,其中益生菌减少,致病菌增多,尤以童虫期、成虫期较重.  相似文献   

10.
目的:研究富含燕麦麸皮饲料对正常大鼠的耐受性和安全性,及其对肠道功能、肠道菌群构成、血糖、血脂水平的影响。方法:SD大鼠分为对照组(基础饲料喂养)和干预组(含燕麦麸皮21.7%饲料喂养),4w实验期间记录大鼠一般生活状况、进食量、体重、血糖、血脂水平、肠道转运时间等指标,第29d处死大鼠,记录盲肠总重、壁重及内容物重量,行肠球菌、肠杆菌、双歧杆菌及乳杆菌特异性培养及计数,测定盲肠内容物氨含量及pH值。结果:喂养4w后,与对照组相比,干预组大鼠盲肠内容物双歧杆菌数量明显上升,盲肠内容物pH值水平明显下降,其他各项指标在2组间未见显著性差异。结论:正常大鼠对干预组剂量的燕麦麸皮安全耐受,燕麦麸皮增加正常大鼠肠道双歧杆菌数量,降低肠道内pH值水平,未观察到其对肠道转运时间、盲肠结构及糖脂代谢水平等指标的影响。  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.
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   

13.
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   

14.
15.
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   

16.
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   

17.
18.
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   

19.
Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H2-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H2 with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD+, FMN+, and NAD(P)+ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H2OCO2+2H++2e- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation  相似文献   

20.
Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)8 barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)8 structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive ET and active ER. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive ET and active ER represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.  相似文献   

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