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21.
丁酸菌是一种专性厌氧芽胞杆菌,是以丁酸为主要代谢产物的益生菌,可定植于人体肠道,在某种程度上与乳酸菌有协同作用,可抑制人肠道内有害菌的生长、促进营养物质的吸收、改善肠道功能等。本研究主要对丁酸菌在临床中的应用研究进展进行综述,尤其是对丁酸菌与老年人肠道功能的相关性进行阐述,并展望丁酸菌对老年慢性疾病如糖尿病、心血管疾病、老年痴呆、风湿性疾病及骨质疏松症防治的研究未来。  相似文献   
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Sequential Monte Carlo p-values   总被引:4,自引:0,他引:4  
BESAG  JULIAN; CLIFFORD  PETER 《Biometrika》1991,78(2):301-304
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BACKGROUND: The analysis of exosomes in blood obtained from the tumor-draining mesenteric vein (MV) can identify tumor biomarkers before they reach target organs and form the premetastatic niche where circulating tumor cells can anchor. Our group has recently shown that microRNAs in plasma from the MV—but not the peripheral vein (PV)—have been related to liver metastases in colon cancer (CC) patients. Here we examine the exosomal protein cargo in plasma from the MV and paired PV in 31 CC patients. PATIENTS AND METHODS: The study included patients who were initially diagnosed with stage I-III CC and 10 healthy controls. Exosomes from the MV and PV of all patients and controls were isolated by ultracentrifugation and confirmed by cryogenic transmission electron microscopy. High-throughput proteomic analysis by mass spectrometry was used to identify expression levels of exosomal proteins. Findings were confirmed by Western blot. RESULTS: Exosomal ECM1 protein was more highly expressed in patients than in controls and was 13.55 times higher in MV from relapsed than relapse-free patients. High exosomal ECM1 expression was associated with liver metastases. Patients with high exosomal ECM1 expression in MV—but not PV—plasma had shorter time to relapse than those with low ECM1 expression (P = .04). CONCLUSION: High levels of exosomal ECM1 protein can identify CC patients with a higher risk of relapse. The analysis of exosomes isolated from the tumor-draining MV is a promising method for the identification of biomarkers before they reach the target organ.  相似文献   
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关于“弱激光血管内照射疗法”的几个问题   总被引:10,自引:0,他引:10  
本文从:1.关于“弱激光血管内照射疗法(IntravacularLow-Reaction-levelLaserIrradiationTherapyILLLT)的中、英文名称问题。2.该疗法引入我国的历史回顾。3.该疗法的临床效果与基础研究。4.该疗法与光量子疗法(UBI)的比较。5.该疗法在我国面临的问题及展望等五个方面以较详实的材料对以He—Ne激光为代表的弱激光血管内照射疗法客观地进行阐述,并以笔者的研究实践及其认识为基础提出看法以期探讨,从而澄清目前国内对该疗法尚存在的某些混乱状况与模糊认识,使其作为弱激光的一种很有前途的临床疗法能走上健康发展的道路。  相似文献   
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目的:研究冠状动脉旁路移植手术后患者B型脑钠钛(BNP)水平变化规律及临床意义。方法:选取我院2014年6月到2015年6月间收治的冠状动脉旁路移植手术患者80名,根据患者心脏左心室射血分数(LVEF)分为A组(45%)和B组(≤45%),观察两组患者在不同时间的BNP水平,对比两患临床相关指标、及心房颤抖和心功能不全发生情况。结果:A组患者在血管活性物质使用量、呼吸机使用时间、监护室停留时间及心房颤抖和心功能不全发生率都明显小于B组,差异有统计学意义(P0.05);术后6h两组患者的BNP水平开始明显上升,在术后24h达到峰值,此后开始下降但仍维持较高水平,组内比较差异均有统计学意义(P0.05)。A组患者在术前及术后各个时间段内BNP水平均明显小于B组,组间比较比较均有统计学意义(P0.05)。结论:冠状动脉旁路移植患者围手术期BNP水平可以反应患者心脏功能状况,BNP水平越高表示患者心脏越差。  相似文献   
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Pore gradient electrophoresis (PGE) in the presence of sodium dodecyl sulfate (SDS) provides a means for high resolution fractionation of multicomponent protein systems and permits estimation of molecular weights for macromolecules ranging from 103 to 106. We have evaluated the performance of several methods used to construct calibration curves for estimation of molecular weights using SDS-PGE. A linear relationship between the logarithm of molecular weight, log (Mr), and the logarithm of the relative mobility, log (Rl), can be obtained for a 30-fold range of molecular weights. However, this range of linearity depends on the choice of the concentration gradient, the degree of crosslinking of the gel, and on the nature of the underlying relationship between the retardation coefficient, KR, and the molecular weight. An empirical relationship, first introduced by Lambin et al. (1976, Anal. Biochem.74, 567) between log (Mr) and the logarithm of the gel concentration at the position reached by the protein, log (%T), provides better linearity over a wider molecular weight range than does the use of log (Rl). We have compared these relatienships by experimental analysis of 10 standard proteins and by a theoretical analysis of an idealized model system. A computer program has been developed which provides appropriate statistical estimation of the molecular weight for an unknown protein, together with its standard error and 95% confidence limits. A new method has also been developed for analysis of nonlinear calibration curves in terms of molecular weight versus distance migrated, based on a theoretically justifiable, physical-chemical model. This model implies that either the relationship between log (Mr) and log (Rl) or the one between log (Mr) and log (%T) will become nonlinear as the range of molecular weight is extended. We suggest that the use of a nonlinear least-squares curve-fitting procedure provides an optimal method for molecular weight estimation when sufficient data are available. Based on these findings, a general strategy is presented for estimation of molecular weights by polyacrylamide gel electrophoresis.  相似文献   
29.
本文根据作者在参考文献[3]所提出的利用各世代小区平均数估计遗传参数的加权最小二乘法对玉米穗粒重的遗传特性进行了分析。结果表明:(1)在本次试验中,可用加性-显性-二基因互作模型来描述玉米穗粒重的遗传特性;其加性效应[d]、加性效应与显性效应的互作[j]在α=0.01水平上显著,显性效应[h]、显性效应与显性效应的互作[l]在α=0.10水平上显著,加性效应与加性效应的互作[i]不显著;[d]与[h]的差异在α=0.10水平上不显著,但([d] [h])与([i] [j] [l])在α=0.05水平上显著;(2)与利用6个世代平均数相比,利用8个世代小区平均数的加权最小二乘法既节约、又灵敏。  相似文献   
30.
The effect of interferon-α (Wellferon) on human monocyte to macrophage maturation in vitro has been investigated. Cell volume and three markers, acid phosphatase, leucine aminopeptidase, and phagocytosis, which increase with maturation, have been studied employing recently developed flow cytofluorometric techniques. The increase in cell volume and in the expression of all three markers was inhibited in a dose-dependent manner in monocyte cultures given 50–300 U/ml of interferon within 2 hr of culture initiation. An initial dose of 300 U/ml of interferon, removed from the cultures after 24 hr, was as effective in inhibiting the development of each of the markers as three 100 U pulses on three consecutive days, and as effective as 300 U interferon left in throughout the culture period. Histogram analysis of marker expression indicated that all monocytes, and not a subpopulation, were affected by the interferon. Cytotoxic activity of freshly isolated monocytes rapidly decayed when the cells were cultured under standard maturation conditions. The addition of interferon to the cultures prevented the loss of this activity while also preventing the development of more mature cells. It appears that maintenance of the cytotoxic state is one influence of interferons; however, it may be that these cells have also been directed toward alternate pathways of macrophage differentiation.  相似文献   
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