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41.
本文报道2例肠梗阻和1例有机磷农药中毒患者出现暂时性高血糖症。该3例患者均无糖尿病史,因有重度失水,经大量补液纠正失水后血糖迅速恢复正常。口服葡萄糖耐量试验正常。作者认为非糖尿病患者可因重度失水而致应激性高血糖症。 相似文献
42.
慢性阻塞性肺疾病(COPD)是一种常见的慢性呼吸系统疾病,对人类健康造成极大威胁。研究发现,COPD患者与健康人群相比,肺部菌群及肠道菌群的组成结构发生了显著改变,导致黏膜屏障功能及机体免疫稳态被破坏,进而加重病情。积极调节肺部、肠道菌群平衡对于干预COPD的发生、发展有着至关重要的作用,但目前关于肺部、肠道菌群及其相互作用机制在COPD中作用的总结和认识还有待进一步阐明。本文就健康人群以及COPD患者肺部、肠道菌群的组成特点及可能的相互作用机制,以及现阶段基于肺部、肠道菌群及其相互作用防治COPD的最新研究成果进行综述,以期为COPD的发病机制、早期诊断、预防与治疗研究提供新思路。 相似文献
43.
目的:比较不同性别BALB/c小鼠采用高脂饮食建立肥胖模型的差异。方法:32只4周龄无特定病原体级BALB/c小鼠(雌雄各半)随机分为雌性对照组、雌性高脂组、雄性对照组和雄性高脂组,每组8只。雌性对照组和雄性对照组采用普通饮食,雌性高脂组和雄性高脂组采用高脂饲料喂养,喂养12周后测量小鼠体重、内脏脂肪比、空腹血糖、葡萄糖耐量、血脂、代谢相关激素水平,并采用16S rRNA测序检测小鼠粪便菌群构成。结果:高脂饮食干预导致雄性小鼠体重和内脏脂肪比明显增加,病理表现为单个脂肪面积明显增大,肝脏脂肪滴堆积,总胆固醇、空腹血糖、口服糖耐量试验时间-血糖曲线下面积以及血清胰岛素水平明显上升(均P<0.05),并出现明显胰岛素抵抗(P<0.01)。而雌性高脂组体重、内脏脂肪比、血清胰岛素和瘦素水平与雌性对照组差异均无统计学意义(均P>0.05)。高脂干预后小鼠肥胖相关肠道菌群相对丰度显著变化并存在性别差异,其中雄性高脂组肥胖相关菌属(如布劳特菌)相对丰度明显增加,菌群结构变化更明显。结论:高脂饮食喂养12周4周龄BALB/c雄性小鼠可稳定建立以内脏脂肪堆积、代谢功能紊乱和肠道菌群变... 相似文献
44.
目的:探索种植体黏膜下微生物在健康种植体和种植体周炎中的构成与差异,并分析与临床指标存在相关性的菌种,为种植体周炎的病因学研究提供参考。方法:采用横断面研究,共纳入49例患者,20例为健康种植体,29例为种植体周炎,共采集49份黏膜下微生物样本进行16S核糖体RNA(16S ribosomal RNA, 16S rRNA)基因高通量测序。对两组样本的多样性、菌群构成和差异物种进行分析和比较,采用Spearman相关性分析评价菌种与探诊深度(probing pocket depth, PPD)之间的相关性。结果:健康组的α多样性显著低于种植体周炎组[Chao1指数:236.85±66.13 vs. 150.54±57.43,P<0.001; Shannon指数:3.42±0.48 vs. 3.02±0.65,P=0.032]。主成分分析显示,两组样本的群落结构差异有统计学意义[相似性分析(analysis of similarities, ANOSIM),R2=0.243,P=0.001]。与健康种植体相比,种植体周炎黏膜下菌斑中的牙周致病菌显著增加,包括红色... 相似文献
45.
M. H. de Vries G. A. Hofman A. Sj. Koster J. Noordhoek 《Naunyn-Schmiedeberg's archives of pharmacology》1989,340(2):239-245
Summary Using the isolated vascularly fluorocarbon emulsion perfused rat small intestine some factors which determine the extent of the intestinal glucuronidation of 1-naphthol to 1-naphthol--d-glucuronide were studied. Increasing the luminal 1-naphthol concentration resulted in a concomitant increase in the 1-naphthol appearance in the vascular perfusate. In contrast, the total appearance of 1-naphthol--d-glucuronide increased less than proportional to the increase in the luminal 1-naphthol concentration. About 88% of the total amount of 1-naphthol--d-glucuronide excreted was released into the vascular perfusate. The capacity-limited intestinal glucuronide efflux is most likely due to saturation of the excretory mechanism for 1-naphthol--d-glucuronide. Decreasing the vascular flow rate influenced both the appearance of 1-naphthol and 1-naphtol--d-glucuronide in the vascular perfusate, whereas the appearance of 1-naphthol--d-glucuronide in the luminal perfusate was essentially flow-independent. A noradrenaline-induced change in the haemodynamic state of the vascular bed (with the total flow kept constant) resulted in a marked decrease in the 1-naphthol vascular concentration. The vascular 1-naphthol--d-glucuronide concentration was only slightly affected. These results indicate that changes in blood flow and blood flow distribution within the intestinal wall can affect the extent of presystemic intestinal metabolism by interfering with the absorption of the parent compound and the efflux of formed conjugates. These parameters can be of paramount importance for causing variable intestinal first-pass effects of drugs in vivo.
Send offprint requests to M. H. de Vries at the above address 相似文献
46.
Patrizia Robino Ilario Ferrocino Giacomo Rossi Andrea Dogliero Valentina Alessandria Lisa Grosso 《Avian pathology》2019,48(2):111-120
Macrorhabdus ornithogaster is an opportunistic yeast that colonizes the gastric mucosa of many avian species. Until now, no studies have focused on the influence of a gastric infection on the balance of the intestinal microbiota of birds. In this study, 44 faecal samples from individual canaries, with and without M. ornithogaster infection, were analysed. The detection of the yeast was evaluated by 18S rRNA PCR. In order to evaluate the impact of the Macrorhabdus infection on the bacterial communities, culture-independent methods, by the use of amplicon-based sequencing as well as 16S rRNA-DGGE, were adopted. The different health status of animals affected the relative abundance of the main OTUs, with a greater diversification of the gut microbiota in healthy animals compared to the infected. In particular, Lactococcus, Pseudomonas, Acinetobacter, Lachnospiraceae, Propionibacterium and Weissella were found to be characteristic of uninfected animals (FDR?<?0.05), while Lactobacillus and Candidatus Arthromitus were characteristic of infected animals (FDR?<?0.05). Both these taxa have been reported as immunostimulatory, involved in immunological disorders. In infected animals the inferred metagenome assessed by PICRUST clearly showed a positive correlation between the presence of M. ornithogaster and KEGG genes related to ether lipid metabolism, already reported to be immunostimulatory by activation of macrophages and to play a pathophysiological role in several immunological disorders. Finally, our results show an interaction between infection of the digestive tract and intestinal microbiota of pet birds and provide insight into the changing of the complex enteric bacterial community.
- HIGHLIGHTS
Macrorabdus ornithogaster is a gastric yeast that colonizes a wide range of birds.
Differences were found between infected and healthy animals in gut microbiota.
Candidatus Arthromitus was closely associated with infected birds.
M. ornithogaster can affect intestinal microbiota composition of canaries.
47.
Intestinal microvillous disorders are an uncommon cause of severe diarrhea, with very poor prognosis. The authors report the case of a female infant with Down syndrome, aganglionic megacolon, severe diarrhea, and jejunal biopsy with ultrastructural changes consistent with microvillous atrophy. The patient condition improved after a colostomy performed in the setting of the treatment of Hirschprung disease. 相似文献
48.
本文对肠道运动进行分析,从结构上研究肠鸣音的产生机理和肠鸣音的时域、频域特点,从而得到其物理模型,并用等效电路来模拟肠鸣音的产生,为研究肠鸣音的数学模型,以及临床医学研究提供了方便。 相似文献
49.
J. Tamarelle A.C.M. Thiébaut B. de Barbeyrac C. Bébéar J. Ravel E. Delarocque-Astagneau 《Clinical microbiology and infection》2019,25(1):35-47
Background
The vaginal microbiota may modulate susceptibility to human papillomavirus (HPV), Chlamydia trachomatis, Neisseria gonorrhoeae and Mycoplasma genitalium infections. Persistent infection with a carcinogenic HPV is a prerequisite for cervical cancer, and C. trachomatis, N. gonorrheae and M. genitalium genital infections are all associated with pelvic inflammatory disease and subsequent infertility issues.Objectives
To evaluate the association between these infections and the vaginal microbiota.Data sources
The search was conducted on Medline and the Web of Science for articles published between 2000 and 2016.Study eligibility criteria
Inclusion criteria included a measure of association for vaginal microbiota and one of the considered STIs, female population, cohort, cross-sectional and interventional designs, and the use of PCR methods for pathogen detection.Methods
The vaginal microbiota was dichotomized into high-Lactobacillus vaginal microbiota (HL-VMB) and low-Lactobacillus vaginal microbiota (LL-VMB), using either Nugent score, Amsel's criteria, presence of clue cells or gene sequencing. A random effects model assuming heterogeneity among the studies was used for each STI considered.Results
The search yielded 1054 articles, of which 39 met the inclusion criteria. Measures of association with LL-VMB ranged from 0.6 (95% CI 0.3–1.2) to 2.8 (95% CI 0.3–28.0), 0.7 (95% CI 0.4–1.2) to 5.2 (95% CI 1.9–14.8), 0.8 (95% CI 0.5–1.4) to 3.8 (95% CI 0.4–36.2) and 0.4 (95% CI 0.1–1.5) to 6.1 (95% CI 2.0–18.5) for HPV, C. trachomatis, N. gonorrhoeae and M. genitalium infections, respectively.Conclusions
Although no clear trend for N. gonorrhoeae and M. genitalium infections could be detected, our results support a protective role of HL-VMB for HPV and C. trachomatis. Overall, these findings advocate for the use of high-resolution characterization methods for the vaginal microbiota and the need for longitudinal studies to lay the foundation for its integration in prevention and treatment strategies. 相似文献50.
Entrainment of Intestinal Slow Waves with Electrical Stimulation Using Intraluminal Electrodes 总被引:3,自引:0,他引:3
The aim of this study was to investigate whether the intestinal stimulation would be feasible using a less invasive method: intraluminal electrodes. The study was performed in nine healthy hound dogs (15–26 kg). Four pairs of electrodes were implanted on the serosa of the jejunum at an interval of 5 cm with the most proximal pair 35 cm beyond the pylorus. An intestinal fistula was made 20 cm beyond the pylorus. Simultaneous recordings of intestinal myoelectrical activity were made for 2 h in the fasting state from both intraluminal and serosal electrodes. Various pacing parameters were tested. The frequency of the intestinal slow wave recorded from the intraluminal electrodes was identical to that from the serosal electrodes
, p < 0.001), and so was the percentage of normal 17–22 cycles/min waves (95.8±33.9% vs 98.16±1.33%, r=0.96, p<0.01).p < 0.01). A complete entrainment of the intestinal slow wave was achieved in every dog with electrical stimulation using intraluminal ring electrodes. The effective pacing parameters were pulse width of 70 ms, amplitude of 4 mA and frequency of 1.1 IF (intrinsic frequency). The time required for the entrainment of the intestinal slow wave with intraluminal pacing was 25.0±2.1s. The maximum driven frequency was found to be 1.43±0.01 IF. The results reveal that intraluminal pacing is an effective and efficient method for the entrainment of intestinal slow waves. It may become a potential approach for the treatment of intestinal motor disorders associated with myoelectrical abnormalities. © 2000 Biomedical Engineering Society.
PAC00: 8754Dt, 8719Ff, 8717Nn 相似文献