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71.
The vertebrate vasculature is an essential organ network with major roles in health and disease. The establishment of balanced cell–cell adhesion in the endothelium is crucial for the functionality of the vascular system. Furthermore, the correct patterning and integration of vascular endothelial cell–cell adhesion drives the morphogenesis of new vessels, and is thought to couple physical forces with signaling outcomes during development. Here, we review insights into this process that have come from studies in zebrafish. First, we describe mutants in which endothelial adhesion is perturbed, second we describe recent progress using in vivo cell biological approaches that allow the visualization of endothelial cell–cell junctions. These studies underline the profound potential of this model system to dissect in great detail the function of both known and novel regulators of endothelial cell–cell adhesion. 相似文献
72.
目的:探讨人胚食管上皮永生化细胞株SHEE、SHEEMT、食管癌细胞株EC8712中PTEN表达的差,判断食管上皮细胞在恶性转化过程中是否有PTEN缺失现象的发生;方法:培养三种细胞株,采用免疫组织化学、激光共聚焦显微镜、流式细胞仪和Westernblot等检测方法对三种细胞株中PTEN的表达进行检测。结果:三种细胞株均有PTEN的表达,表达强度与分化程度有关,PTEN在三种细胞株中表达强弱顺序为SHEE>SHEEMT>EC8712,差异有统计学意义(P<0.01);结论:PTEN在SHEE、SHEEMT和EC8712三种来源于食管鳞状上皮但分化程度不同的细胞株均中表达,表达强度与分化程度相关,分化程度越高,表达越强。 相似文献
73.
Esophageal cancer (EC) is characteristic of early regional lymph node metastasis (LNM) and most patients with metastasis have a poor prognosis. However, the current diagnostic techniques do not enable precise differentiation of EC LNM, prognostic stratification, and individual survival estimation. To identify potential molecular biomarkers for EC patients with LNM, we explored differently expressed genes in The Cancer Genome Atlas database between 77 non-LNM cases and 88 LNM cases by limma package R. Then, according to univariate and multivariate Cox regression analyses, we constructed an 8-messenger RNA (mRNA) prognostic signature model, which could predict the outcome in a more exact way. The area under the curve of the risk score is significantly higher than other clinical information, indicating that the 8-mRNA–based risk score is a good indicator for prognosis. Then, combined with other individual risk factors, such as age, sex, T stage, M stage, etc, we could precisely calculate the individual 1-, 3-, and 5-year survival rates. The Gene Set Enrichment Analysis, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes analysis indicate that the risk model is mainly associated with cancer-related pathways, such as cell division, cellular meiosis, and cell cycle regulation. In summary, the 8-mRNA–based risk score model that we developed successfully predicts the survival of EC. It is independent of clinical information and performing better than other clinical information for prognosis. 相似文献
74.
<正>Liver cirrhosis is the pathologic end stage of multiple liver diseases.The major complications of liver cirrhosis,such as hepatic encephalopathy,spontaneous bacterial peritonitis and esophageal variceal bleeding are characterized by remarkable changes of the gut microbiota,which indicates that enteric dysbiosis might play an important role in the progression of liver cirrhosis[1,2].The human gastrointes- 相似文献
75.
Marcelle Bergeron† Margaret S. Swain† Tomás A. Reader† Louise Grondin† Roger F. Butterworth† 《Journal of neurochemistry》1990,55(1):222-229
Four weeks following portacaval anastomosis (PCA) in the rat, severe liver atrophy, sustained hyperammonemia, and increased plasma and brain tryptophan are observed. Administration of ammonium acetate (NH4Ac) to rats with PCA precipitates severe signs of hepatic encephalopathy (HE) (loss of righting reflex progressing to loss of consciousness and ultimately deep coma). To evaluate the relationship between the deterioration of neurological status in HE and serotonin (5-HT) metabolism, the levels of 5-HT, its precursor 5-hydroxytryptophan, and its major metabolite 5-hydroxy-indole-3-acetic acid (5-HIAA) were measured by HPLC with ion-pairing and electrochemical detection in three well-defined areas of the cerebral cortex: anterior cingulate, piriform and entorhinal, and frontoparietal; as well as in the caudate-putamen, the raphe nuclei, and the locus ceruleus in rats with PCA at different stages of HE, before and after injection of NH4Ac, as well as in sham-operated controls. The results demonstrate increased 5-HIAA/5-HT ratios after PCA and NH4Ac loading, suggesting increased 5-HT turnover in the brains of these animals. However, these changes do not appear to be related to the precipitation of coma as no significant difference in 5-HT turnover was observed between precoma and coma stages of HE. Increased 5-HT turnover in brain of shunted rats may be related to early symptoms of HE such as altered sleep patterns and disorders of motor coordination. 相似文献
76.
Helicobacter pylori infection reduces the risk of Barrett's esophagus: A meta‐analysis and systematic review 下载免费PDF全文
Bálint Erőss Nelli Farkas Áron Vincze Benedek Tinusz László Szapáry András Garami Márta Balaskó Patrícia Sarlós László Czopf Hussain Alizadeh Zoltán Rakonczay Jr Tamás Habon Péter Hegyi 《Helicobacter》2018,23(4)
Introduction
The prevalence of Helicobacter pylori infection (HPI) has been decreasing in developed countries, with an increasing prevalence of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) at the same time. The aim of our meta‐analysis was to quantify the risk of BE in the context of HPI.Methods
A systematic search was conducted in 3 databases for studies on BE with data on prevalence of HPI from inception until December 2016. Odds ratios for BE in HPI were calculated by the random effects model with subgroup analyses for geographical location, presence of dysplasia in BE, and length of the BE segment.Results
Seventy‐two studies were included in the meta‐analysis, including 84 717 BE cases and 390 749 controls. The overall analysis showed that HPI reduces the risk of BE; OR = 0.68 (95% CI: 0.58‐0.79, P < .001). Subgroup analyses revealed risk reduction in Asia OR = 0.53 (95% CI: 0.33‐0.84, P = .007), Australia OR = 0.56 (95% CI: 0.39‐0.80, P = .002), Europe OR = 0.77 (95% CI: 0.60‐0.98, P = .035), and North‐America OR = 0.59 (95% CI: 0.47‐0.74, P < .001). The risk was significantly reduced for dysplastic BE, OR = 0.37 (95% CI: 0.26‐0.51, P < .001) for non‐dysplastic BE, OR = 0.51 (95% CI: 0.35‐0.75, P = .001), and for long segment BE, OR = 0.25 (95% CI: 0.11‐0.59, P = .001) in case of HPI.Conclusions
This extensive meta‐analysis provides additional evidence that HPI is associated with reduced risk of BE. Subgroup analyses confirmed that this risk reduction is independent of geographical location. HPI is associated with significantly lower risk of dysplastic, non‐dysplastic, and long segment BE. 相似文献77.
目的:探讨食管癌根治术后肺部感染的病原菌及耐药性,为临床合理应用抗菌药物提供依据。方法:选择2009年1月-2017年12月在我院行食管癌根治术的764例患者作为研究对象,记录患者临床基本资料,采集肺部感染患者深部痰液标本进行细菌培养,并对病原菌进行药物敏感性试验,分析其病原菌分布和耐药性。结果:764例食管癌根治术后患者肺部感染146例,感染率为19.11%;肺部感染患者痰液标本培养获得病原菌185株,其中革兰阴性菌116株,占62.70%,以铜绿假单胞菌和肺炎链球菌最多,分别占18.38%和14.05%;革兰阳性菌40株,占21.62%,以金黄色葡萄球菌最多,占8.65%;真菌29株,占15.68%,以白假丝酵母菌最多,占9.19%。铜绿假单胞菌、肺炎链球菌、鲍氏不动杆菌、大肠埃希菌对美洛西林的耐药率最高,分别占70.59%、73.08%、86.96%、62.50%,对亚胺培南耐药率最低,分别占5.88%、3.85%、26.09%、12.50%。金黄色葡萄球菌、表皮葡萄球菌对头孢唑林的耐药率最高,分别占81.25%、63.64%,溶血葡萄球菌对头孢唑林、阿奇霉素、环丙沙星的耐药率最高,均占71.43%,肠球菌对头孢唑林、环丙沙星耐药率最高,均占100.00%;黄色葡萄球菌、表皮葡萄球菌、溶血葡萄球菌、肠球菌对万古霉素耐药率最低,均为0.00%。结论:食管癌根治术后肺部感染以革兰阴性菌为主,病原菌主要对美洛西林、头孢唑林、阿奇霉素、环丙沙星产生耐药性,对亚胺培南、万古霉素耐药性较低,临床应合理选用抗菌药物进行治疗。 相似文献
78.
79.
Strains of Rhizoctonia solani, a common soil-borne, pathogenic fungus of plants, are assigned to one of 11 anastomosis groups (AGs) based on the occurrence of imperfect fusions (anastomoses) between hyphae of a non-typed strain and a tester strain of one of the 11 AG's. Imperfect fusion is characterized by the death of one or more cells in each of the hyphae involved in the fusion. Although hyphae from branches of the same strain of JR. solani may fuse with each other (self-fusion), cell death does not occur. Cell death is accompanied by nuclear degradation and granulation, or plasmolysis of the cytoplasm, which often is not visible using bright-field microscopy. When the DNA-binding fluorochrome DAPI (4', 6-diamidino-2-phenylindole) is used and the hyphal fusions viewed under fluorescence microscopy, no nuclei are observed in fused hyphal cells from two strains of the same AG of R. solani Because DAPI reacts only with living nuclei, lack of staining is presumptive evidence that the fused cells are dead as a result of imperfect fusion. The use of DAPI reduces the time required for making AG determinations compared to standard methods because it eliminates the need to assess cell wall dissolution and cytoplasmic fusion. Also, it is not necessary to trace the hyphae involved in the fusion to their respective origins to ensure that self-fusion has not occurred. 相似文献
80.
- 1. 1. This study examined the effect of inhaling air supersaturated with water on changes of core temperatures in submaximally exercising males.
- 2. 2. During exercise with inhalation of supersaturated relative to low-air-humidity air, a significant elevation in tympanic temperature (P = 0.009) and a significant decrease in esophageal temperature (P = 0.004) were observed.
- 3. 3. Forehead skin temperatures significantly decreased during humidified air inhalation (P = 0.02) supporting that this treatment induced greater thermolytic responses that cooled the skin.
- 4. 4. The results are consistent with the conclusion that heat loss from the upper airways directly influenced human cerebral temperatures as indexed by tympanic temperatures.