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1.
目的研究新疆昆仑雪菊水提物对小鼠肠道短链脂肪酸的影响。方法 C57BL/6小鼠随机分为4组:空白对照组(n=10)、高剂量组(n=10)、中剂量组(n=10)和低剂量组(n=10),给药14 d,用气相色谱法测定粪样中乙酸、丙酸、丁酸水平。结果相比空白对照组,低剂量组小鼠肠道粪样中乙酸水平显著升高(F=4.662,P=0.011),丙酸水平显著降低(F=3.097,P0.007),中剂量组与高剂量组比较差异无统计学意义。乙酸与乳杆菌属呈正相关(r=0.491,P=0.017),丙酸与乳杆菌属呈负相关(r=-0.425,P=0.038)。结论新疆昆仑雪菊水提物对小鼠肠道短链脂肪酸具有一定的调节作用。  相似文献   

2.
为评价螺旋藻对肠道菌群的影响, 采用注射氨苄青霉素的方法, 制造小鼠腹泻模型, 造模成功后灌服不同剂量螺旋藻进行治疗, 取不同治疗时间的粪便样品, 检测双歧杆菌、乳杆菌、大肠杆菌、肠球菌、拟杆菌、产气荚膜梭菌菌群的数量,并在螺旋藻灌胃8 d后, 测定小鼠不同肠段各指标菌群的数量。结果表明, 中高剂量组螺旋藻对腹泻模型小鼠肠道菌群有明显调整作用, 有效缩短了肠道菌群由失调到平衡的时间;粪便样品同各肠段内容物所反映的菌群的变化趋势相同, 即治疗恢复组的双歧杆菌、乳杆菌数量总体上高于生理盐水组, 肠杆菌、肠球菌、拟杆菌、产气荚膜梭菌数量均低于生理盐水组, 但取样位置不同, 各指标菌群的数量明显存在差异。  相似文献   

3.
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   

4.
目的 研究合生无益生菌冲剂对小鼠肠道菌群的调节作用.方法 将小鼠分为阴性对照组、合生元益生菌冲剂组.阴性对照组灌服蒸馏水14 d,合生元益生菌冲剂组灌服1 g/kg·d剂量的台生元益生菌冲剂14 d,检测实验前后肠道菌群数量.结果 灌服后小鼠肠道菌群与灌服前比较,,双歧杆菌数量有显著性增加(P<0.05),肠杆菌、肠球菌、乳杆菌和产气荚膜梭菌数量有无显著性变化(P>0.05).结论 合生元益生菌冲剂对小鼠肠道菌群具有一定的调节作用.  相似文献   

5.
目的研究新型嗜酸乳杆菌NCFM-乳双歧杆菌Bi-07-鼠李糖乳杆菌NH001三联益生菌制剂对便秘小鼠小肠蠕动的促进作用,以及其对小鼠肠道菌群构成比例的调节作用。方法小肠推进率实验:将50只KM小鼠适应性饲养后随机分为空白对照组、模型对照组和低中高三个剂量组。空白对照组和模型对照组给予蒸馏水,低中高剂量组每天分别给予0.165、0.330、0.990g/(kg·bw)益生菌制剂,灌胃14d后使用复方地芬诺酯建立小鼠便秘模型观察小肠墨汁推进率;肠道菌群调节作用实验:将42只BALB/c小鼠中随机抽取10只作为自身对比空白组,适应性饲养后将所有小鼠随机分为空白对照组和低中高三个剂量组,空白对照组给予蒸馏水,各剂量组以相同剂量给予益生菌制剂灌胃。自身对比空白组于灌胃前无菌采集小鼠直肠粪便,所有小鼠灌胃30d后无菌采集直肠粪便,使用16SrDNA基因测序对粪便中菌群DNA进行多样性及各水平菌群物种测定。结果高剂量组便秘小鼠小肠推进率显著高于模型对照组(P0.05);各剂量组肠道菌群多样性、双歧杆菌属、乳杆菌属数量较灌胃前显著增加(P0.05),大肠埃希菌属、梭菌属、肠球菌属较灌胃前显著降低(P0.05)。结论三联益生菌能够有效促进便秘小鼠肠道蠕动能力,改善便秘症状;同时对小鼠肠道菌群结构有调节作用。  相似文献   

6.
断奶仔猪肠道菌群的研究   总被引:19,自引:1,他引:18  
研究断奶仔猪在不同生理状况下的肠道菌群,结果表明:健康仔猪肠道内容物中,从十二指肠到结肠,所测定的8种细胞数量都随肠段后移而逐渐增加,43日龄仔猪肠道内容物中以乳杆菌、肠球菌和梭菌占绝对优势,双歧杆菌次之;与健康仔猪相比,下痢仔猪肠道中肠球菌、梭菌和乳杆菌等优势菌群的数量明显低于对照组;饲喂了含肠球菌的活菌制剂的仔猪肠道中双歧杆菌和类杆菌的数量比对照组明显增加,但肠球菌数量却无显著改变。  相似文献   

7.
目的研究栀子豉汤及栀子、淡豆豉对6种人肠道菌的影响。方法从特定人的粪便中分离培养肠杆菌、肠球菌、双歧杆菌、乳杆菌、产气荚膜梭菌和脆弱拟杆菌。分别将高、中、低浓度的栀子、淡豆豉及栀子豉汤药液加入选择性培养基中,以不加药液的培养基作为空白对照,将实验菌分别于厌氧或有氧条件下培养,计数菌落。结果不同浓度的栀子对肠杆菌的抑制率均为100.0%,淡豆豉在20%、50%、70%浓度分别使肠杆菌数量下调100.00%、53.83%和22.11%,而栀子豉汤可使肠杆菌数量维持在一定水平(104~106 CFU/g);两味药单独都表现了对肠球菌较强的抑制作用,而低、中浓度栀子豉汤则使肠球菌保持较稳定的数量;单味药及复方对产气荚膜梭菌和双歧杆菌敏感性较弱;栀子对脆弱拟杆菌抑制作用最强,而淡豆豉和栀子豉汤则可使其数量上调约20.00%;淡豆豉、栀子豉汤和高浓度栀子对乳杆菌非常敏感,低、中浓度栀子对乳杆菌数量仅有轻微下调作用。结论栀子豉汤比单独的栀子和淡豆豉更能维持肠道菌群的相对平衡。  相似文献   

8.
本实验研究菊苣根超微粉对免疫抑制小鼠肠道菌群的影响,为菊苣的进一步开发利用提供理论依据。应用环磷酰胺(cyclophosphamide,CY)制备免疫功能抑制模型,小鼠分为空白对照组、CY模型组、菊苣根超微粉高剂量组、低剂量组。以菌落计数法检测其盲肠内容物中乳酸杆菌、双歧杆菌、肠杆菌和肠球菌的数量,以ELISA检测肠黏膜分泌型免疫球蛋白A(secretory immunoglobulin A,s Ig A)含量。与CY模型组相比,菊苣根超微粉高剂量组小鼠肠道的乳酸杆菌、双歧杆菌数量显著增加,大肠杆菌、肠球菌数量显著降低,肠道s Ig A含量显著升高。菊苣根超微粉对CY所致的免疫抑制小鼠肠道菌群紊乱有恢复作用。  相似文献   

9.
肠道菌群正常参考值的检测   总被引:29,自引:2,他引:27  
目的定性定量检测并比较杭州地区健康青壮年及老年人群肠道主要菌群(双歧杆菌属、类杆菌属、消化链球菌属、产气荚膜梭菌、乳杆菌属、肠杆菌科、肠球菌属及酵母菌等)的正常参考值,同时计算并比较双歧杆菌属细菌数量与肠杆菌科细菌数量的对数值比值(B/E值).方法采用光冈法 .结果老年组肠道双歧杆菌数量及B/E值较青壮年组均显著减少(P<0.05, P<0.001);消化链球菌、肠杆菌科及肠球菌细菌数量显著增加(P<0.01,P <0 .001,P<0.05).结论在获得肠道菌群正常参考值的同时,发现随着年龄的增加,老年人肠道双歧杆菌数量明显减少,肠杆菌科及肠球菌细菌数量显著增加.  相似文献   

10.
目的观察复方薏苡仁方调节小鼠肠道菌群功能及胃肠运动的效果,并考察复方薏苡仁方对小鼠盲肠内容物pH及肠黏膜结构等肠道内环境的影响。方法参照《保健食品检验与评价技术规范》(2003版)的规定进行调节肠道菌群实验和小肠墨汁推进试验,检测小鼠盲肠内容物pH,并对肠道黏膜结构进行病理形态学观察。结果 (1)与给样前相比,复方薏苡仁方中、高剂量组肠杆菌数和低、高剂量组肠球菌数均明显减少(P0.05),中、高剂量组乳杆菌数和双歧杆菌数均明显或显著增加(P0.05或P0.01),且高剂量组乳杆菌数和中、高剂量组双歧杆菌数明显高于阳性对照组(P0.05);(2)复方薏苡仁方各剂量组小鼠盲肠内容物pH值均显著降低(P0.01),且均低于阳性对照组,其中低、高剂量组差异有统计学意义(P0.05或P0.01);(3)与正常对照组相比,复方薏苡仁方低、中、高剂量组小鼠十二指肠、空肠、回肠绒毛长度/隐窝深度比值(A/V)均明显或显著增加(P0.05或P0.01),且中、高剂量组十二指肠、空肠及回肠A/V比值明显或显著高于阳性对照组(P0.05或P0.01);(4)与模型对照组相比,复方薏苡仁方各剂量组小鼠小肠推进率均显著增加(P0.01),且均高于阳性对照组(P0.01)。结论复方薏苡仁方对调节肠道菌群及改善肠道微环境具有一定的促进作用。  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.
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   

15.
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.
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   

18.
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   

19.
20.
(鱼句)亚科花(鱼骨)型鱼类骨骼系统的比较   总被引:2,自引:0,他引:2  
对我国花型Hemibarbuspattern鱼类作了骨骼系统比较,结果表明,此类型鱼类脑颅较长,副蝶骨平直或稍弯曲,眶蝶骨腹纵嵴发达(铜鱼Coreius septentrionalis例外),下颞窝和咽突中等大,基枕骨后突发达;脑颅中的上筛骨的后突、侧筛骨的外筛突,蝶耳骨的外突、上耳骨的后突、围眶骨和后颞窝等均有明显的差异;咽颅中的舌颌骨、尾舌骨、鳃盖骨和下咽齿的列数等又有显著的区别;附肢骨骼中的腰带骨、脊椎骨中的复合神经骨和第4椎骨腹侧的悬器等也有不同之处。据此,这些差异和区别可作为属间或种间的分类依据。  相似文献   

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