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991.
Q. F. Pan W. T. Li H. C. Dong Y. Z. Chen L. Yin W. Liu W. W. Wang D. Liu S. G. Li W. Y. Gu J. Z. Chen L. Yang W. J. Zhang F. Li 《Diseases of the esophagus》2014,27(4):396-402
Aberrant DNA methylation of promoter region CpG islands may serve as an alternative mechanism to genetic defects in the inactivation of tumor suppressor genes (TSGs) in human malignancies. The aim of this study was to examine the promoter methylation status of the PTEN TSG and its association with esophageal squamous cell carcinoma (ESCC) carcinogenesis in a Chinese Kazakh population, which is known to have a relatively high ESCC incidence and mortality. The methylation status of the PTEN promoter region was determined in patients with ESCC (n = 95) and healthy individuals (n = 65) using highly sensitive Sequenom Epityper assays. The methylation level of the PTEN gene was significantly higher in patients with ESCC than in healthy controls. The median methylation level was 10.0% (interquartile range [IQR]: 7.0–11.0%) in patients with ESCC and 6.0% in controls (IQR: 4.0–9.0%; P = 0.001). PTEN methylation levels were higher in male patients with ESCC than in male controls, whereas a trend toward significance was observed between female patients with ESCC and female controls (P = 0.005 and P = 0.086, respectively). The PTEN methylation level was associated with histopathological grade and lymph node metastasis in patients with ESCC (P = 0.002 and P = 0.009, respectively). To our knowledge, this is the first report to show the presence of PTEN promoter CpG hypermethylation in ESCC and its association with tumor metastasis. 相似文献
992.
视频脑电图监测对癫痫的诊断价值 总被引:11,自引:1,他引:11
目的探讨视频脑电图(Video-EEG)对癫痫的诊断价值.方法对252例发作性疾病患者进行连续12~24小时监测,其中包括清醒、睡眠及诱发试验,分析临床发作和异常放电的关系,异常放电出现的时相,癫痫分型与异常放电的关系,临床发作前脑电图的改变以及临床发作间期和发作期异常脑电图的不同表现.结果252例监测到临床发作142例,其中同时伴异常放电者为111例;252例检出异常放电187例,其中出现于睡眠期者146例;确诊的111例中103例确定了发作类型,其中25例修正了发作类型;确诊的111例监测到发作前脑电图的异常改变,表现为背景脑电波频率和波幅的改变,或者出现痫样放电;111例不同发作类型癫痫患者发作间期和发作期有不同的异常脑电图表现.结论视频脑电图可提高痫样放电的检出率,有助于癫痫的诊断及分型,有利于观察癫痫患者发作间期及发作期脑电图的表现. 相似文献
993.
强迫症的局部脑血流动态显像研究 总被引:4,自引:2,他引:4
目的 探讨强迫症患者各脑叶的代谢状态及脑功能异常与其发病的关系。 方法 采用单光子发射计算机扫描 (SPECT)技术 ,对未服药的 2 2例强迫症患者于静息及症状诱发状态下行局部脑血流 (rCBF)动态显像研究。 结果 1 8例有rCBF异常 ,表现为皮层内局限性放射性分布稀疏、缺损区 ,异常脑叶主要为顶叶、额叶、颞叶 ,并发现脑功能异常与强迫症状的严重程度及药物治疗反应有关。 结论 大脑顶叶、额叶等脑叶的功能异常是部分强迫症发病的神经病理学基础 相似文献
994.
K Lance Gould Tinsu Pan Catalin Loghin Nils P Johnson Ashrith Guha Stefano Sdringola 《Journal of nuclear medicine》2007,48(7):1112-1121
Cardiac PET combined with CT is rapidly expanding despite artifactual defects and false-positive results due to misregistration of PET and CT attenuation correction data-the frequency, cause, and correction of which remain undetermined. METHODS: Two hundred fifty-nine consecutive patients underwent diagnostic rest-dipyridamole myocardial perfusion PET/CT using (82)Rb, a 16-slice PET/CT scanner, helical CT attenuation correction with breathing and also at end-expiratory breath-hold, and averaged cine CT data during breathing. Misregistration on superimposed PET/CT fusion images was objectively measured in millimeters and correlated with associated quantitative size and severity of PET defects. Misregistration artifacts were defined as PET defects with corresponding misregistration on helical CT-PET fusion images that resolved after correct coregistration using a repeat CT scan, cine CT averaged attenuation during normal breathing, or shifted cine CT data that coregistered with PET data. RESULTS: Misregistration of standard helical CT PET images caused artifactual PET defects in 103 of 259 (40%) patients that were moderate to severe in 59 (23%) (P = 0.0000) and quantitatively normalized on cine or shifted cine CT PET (P = 0.0000). Quantitative misregistration was a powerful predictor of artifact size and severity (P = 0.0000), particularly for transaxial misregistration >6 mm occurring in anterior or lateral areas in 76%, in inferior areas in 16%, and at the apex in 8% of 103 artifactual defects. CONCLUSION: Misregistration of helical CT attenuation and PET emission images causes artifactual defects with false-positive results in 40% of patients that normalize on cine CT PET using averaged CT attenuation data during normal breathing comparable to normal breathing during PET emission scanning and shifting cine CT images to coregister visually with PET. 相似文献
995.
公共卫生服务的提供,对于一个国家和社会来说是极为重要的.目前,我国公共卫生事业存在着群众承担的卫生费用增长过快、政府财政投入严重不足、医疗卫生资源城乡分布不合理及政府对公共卫生服务监督职能的缺位等问题.文章提出了对公共卫生服务提供方式的构建设想,包括明确公共卫生基本服务内容、突发公共卫生事件的危机管理、大力发展社区卫生... 相似文献
996.
目的 通过体外研究初步探讨缺氧可以诱导胶质瘤细胞逆分化形成肿瘤干样细胞.方法 ①采用CD133+细胞免疫磁珠分选法分离胶质瘤细胞得到CD133-细胞群.②缺氧处理CD133-细胞48 h后行免疫荧光染色鉴定肿瘤干细胞样标记蛋白(SOX2,OCT-4,KLF-4,Nanog,CD133)表达情况,并分别缺氧处理0、3、6、9、12、24 h及0、12、24、48、72 h行qRT-PCR及Western blot检测.流式细胞术检测胶质瘤细胞缺氧培养后CD133+细胞比例变化,检测时间为缺氧培养1、3、5、7d.③缺氧处理胶质瘤细胞1、3、5、7d后流式分析细胞周期及凋亡改变.结果 ①荧光检测结果表明,肿瘤干细胞样标记蛋白在CD133-胶质瘤细胞缺氧处理48 h后高表达;qRT-PCR及Western blot检测结果表明,缺氧处理胶质瘤细胞可以明显上调肿瘤干细胞样蛋白表达(P<0.05),其中qRT-PCR显示SOX-2,OCT-4及Nanog最高表达在缺氧后9h,KLF-4及CD133在缺氧后12h表达最高.Westem blot蛋白检测显示OCT-4最高表达在缺氧后12 h,CD133表达最高在缺氧24h后,KLF-4及Nanog最高表达则在缺氧48 h后,SOX-2在缺氧72 h后表达量最高.另外随着缺氧时间的延长,CD133+细胞数比例逐渐升高(P<0.05).②细胞周期结果提示缺氧处理肿瘤细胞后,Go/G1期延长,G2/M+S缩短(P<0.05);凋亡结果提示常氧培养组更易凋亡(P<0.05).结论 缺氧可以诱导CD133-胶质瘤细胞肿瘤干样细胞形成. 相似文献
997.
Pan Jing-xin Guo Yi-bin Guo Xi-zhe Guo Jian-xin Chen Yun-feng Wang Zhi-dong 《中国结合医学杂志》2004,10(1):36-39
Objective: To explore the effect of Shenfu Injection, SFI) on the secondary aplastic anemia (AA) of tumor patients after chemotherapy
(CT).Methods: The 15 cases of SFI treated group, 10 cases of control group, 25 cases of SFI + granulocyte-macrophage colony stimulating
factor (GMCSF) treated group and the group of 23 GM-CSF-treated tumor cases of secondary AA after CT were compared, with their
increasing rate and the rebound speed of neutrophil, platelet, bone marrow nucleated RBC, granulocyte, and megakaryocyte all
being investigated.Results: The increasing rate and rebound speed of granulocyte, platelet, and the increasing rate of bone marrow nucleated RBC, granulocyte,
megakaryocyte were obviously higher than those of the control, and the clinical manifestations were also obviously improved.
The increasing rate of platelet, bone marrow nucleated RBC, megakaryocyte of the SFI + GM-CSF group were higher than those
of the group which used GM-CSF alone, while the increasing rate of granulocyte in blood and bone marrow in both groups was
similar.Conclusion: Significant efficacy was shown in SFI for the treatment of secondary AA of tumor patients after CT. 相似文献
998.
Diffusion tensor imaging was performed in 105 volunteers free of central nervous system lesions.No differences were found in fractional anisotropy between the left and right cerebral peduncles among subjects(P > 0.05).The lower limit value of fractional anisotropy was 0.36,and the asymmetry ratio was 0.77.The area and lower limit value of the cerebral peduncles were 0.90 cm2 and 0.83,respectively.These results will be useful in evaluating the diagnosis of Wallerian degeneration following cerebral infarction. 相似文献
999.
Human brain imaging of nicotinic acetylcholine α4β2* receptors using [18F]Nifene: Selectivity,functional activity,toxicity, aging effects,gender effects,and extrathalamic pathways 下载免费PDF全文
Jogeshwar Mukherjee Patrick J. Lao Tobey J. Betthauser Gurleen K. Samra Min‐Liang Pan Ishani H. Patel Christopher Liang Raju Metherate Bradley T. Christian 《The Journal of comparative neurology》2018,526(1):80-95
Nicotinic acetylcholinergic receptors (nAChR's) have been implicated in several brain disorders, including addiction, Parkinson's disease, Alzheimer's disease and schizophrenia. Here we report in vitro selectivity and functional properties, toxicity in rats, in vivo evaluation in humans, and comparison across species of [18F]Nifene, a fast acting PET imaging agent for α4β2* nAChRs. Nifene had subnanomolar affinities for hα2β2 (0.34 nM), hα3β2 (0.80 nM) and hα4β2 (0.83 nM) nAChR but weaker (27–219 nM) for hβ4 nAChR subtypes and 169 nM for hα7 nAChR. In functional assays, Nifene (100 μM) exhibited 14% agonist and >50% antagonist characteristics. In 14‐day acute toxicity in rats, the maximum tolerated dose (MTD) and the no observed adverse effect level (NOAEL) were estimated to exceed 40 μg/kg/day (278 μg/m2/day). In human PET studies, [18F]Nifene (185 MBq; <0.10 μg) was well tolerated with no adverse effects. Distribution volume ratios (DVR) of [18F]Nifene in white matter thalamic radiations were ~1.6 (anterior) and ~1.5 (superior longitudinal fasciculus). Habenula known to contain α3β2 nAChR exhibited low levels of [18F]Nifene binding while the red nucleus with α2β2 nAChR had DVR ~1.6–1.7. Females had higher [18F]Nifene binding in all brain regions, with thalamus showing >15% than males. No significant aging effect was observed in [18F]Nifene binding over 5 decades. In all species (mice, rats, monkeys, and humans) thalamus showed highest [18F]Nifene binding with reference region ratios >2 compared to extrathalamic regions. Our findings suggest that [18F]Nifene PET may be used to study α4β2* nAChRs in various CNS disorders and for translational research. 相似文献
1000.
Anxin Wang Yijun Zhang Guangxin Xia Xue Tian Yingting Zuo Pan Chen Yongjun Wang Xia Meng Xinsheng Han 《CNS Neuroscience & Therapeutics》2023,29(5):1357-1367