摘要目的 研究正常人群粪便和乙状结肠样本中的菌群种属分布特点.方法 采用16sDNA测序技术对13例新鲜粪便样本及10例乙状结肠黏膜样本菌群分布进行鉴定,并对其差异及特定的菌群进行分析.结果 粪便样本中的菌群多样性和丰度均高于乙状结肠黏膜组织,差异有统计学意义(P ＜0.001,P＜0.001,P=0.042,P=0.006).门水平菌群类别相同,包括厚壁菌门、拟杆菌们、变形菌门和放线菌门,但含量不同,粪便样本厚壁菌门和拟杆菌们显著高于乙状结肠黏膜组织,而变形菌门则显著低于乙状结肠黏膜组织,差异有统计学意义(P ＜0.001,P=0.025,P＜0.001).在属水平,粪便菌群以Faecalibacterium菌和拟杆菌属为主,乙状结肠黏膜组织以假单胞菌属、乳球菌属、不动杆菌属和黄杆菌属为主.两组中双歧杆菌、乳酸杆菌等益生菌数量均较低.结论 粪便样本和乙状结肠黏膜组织中菌群分布差异明显.

abstractsObjective To study the distribution patterns of bacterial flora in sigmoid colon tissues and stools in normal population.Method Bacterial flora were identified and analyzed by using 16sDNA sequencing technology in fresh stool samples (n =13) and colon mucosa samples (n =10).Results The diversity and abundance of bacterial flora were significantly larger in the stool samples than in the sigmoid colon samples (P ＜ 0.001,P ＜ 0.001,P =0.042,P =0.006).The consititution of phylum flora between the two groups were same,including flrmicutes,bacteroides,proteobacteria,and actinomycetes.However,the proportions of firmicutes and bacteroides in stool samples were significantly higher than in the sigmoid colon samples,whereas the proportion of proteobacteria was significantly lower (P ＜ 0.001,P =0.025,P ＜ 0.001).At the genus level,faecalibacterium and bacteroides were the dominant flora in feces,whereas pseudomonas,lactococcus,acinetobacter,and flavobacterium were the most common flora in sigmoid colon mucosa.The amounts of bifidobacterium and lactobacillus were low in both two groups.Conclusion The distribution of bacterial flora remarkably differ in stools and sigmoid colon mucosa.