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41.
Mitsuru Izumisawa DDS Masanori Shozushima DDS PhD Hirotaka Sato DDS PhD 《Oral Radiology》2003,19(2):47-55
Objectives It is known that, in fluorine-18 fluorodeoxyglucose Positron Emission Tomography (FDG PET) for the diagnosis of oral cancer,
FDG uptake may vary even among different cases of the same squamous cell carcinoma. However, the details of this phenomenon
have not yet been elucidated. In this study, we analyzed the relationship between histopathological findings in oral squamous
cell cancer and PET findings on FDG uptake.
Methods We examined 45 patients with oral squamous cell carcinoma who had undergone FDG PET before treatment. FDG uptake was assessed
by a standardized uptake value (SUV) calculated according to the PET-measured tissue concentration of FDG, the administered
dose of radionuclide, and the body weight of the patient. The relationship between the mean SUV and each of the following
parameters was examined: histological grade of malignancy, degree of cell differentiation, size and/or local extent of the
primary lesion, and cell density of the tumor.
Results The mean SUV of FDG uptake did not depend on the histological grade of malignancy or on the degree of cell differentiation,
but tended to be greater the larger the primary lesion. SUV also depended on cell density, increasing with the percentage
of tumor parenchyma.
Conclusions It is concluded that cancer cell density greatly influences the SUV of FDG, in that a tumor with fewer cellular elements in
cancer tissue tends to become a false negative. 相似文献
42.
2型糖尿病(消渴病)微观辨证的临床研究 总被引:4,自引:0,他引:4
目的 为糖尿病的临床辨证、治疗用药提供客观依据和帮助。方法 观察 2型糖尿病 (消渴病 ,diabetesmellitus)不同证型患者各 30例 ,正常对照组 30例 ,检测血清一氧化氮 (NO)、血浆α -颗粒膜蛋白 (GMP 14 0 )、血浆D -二聚体 (D D)、血清白细胞介素 - 6 (IL 6 )这些微观指标的变化 ,探讨其与中医辨证分型的关系。结果 ①血清NO值在各组中的变化是阴虚热盛组 >正常对照组>气阴两虚组 >气滞血瘀组 ,每两组间具有显著性差异 (P <0 0 5 ) ,其中气滞血瘀组与其它 3组具有非常显著性差异 (P <0 0 1)。②糖尿病各组患者血浆GMP 14 0、D D值均较正常对照组有非常显著性增高 (P <0 0 1) ,在糖尿病组各证型中 ,呈阴虚热盛组 <气阴两虚组 <气滞血瘀组变化趋势 ,且血浆GMP 14 0和D D的变化呈正相关 (r=0 6 6 )。③血清IL 6在糖尿病组较正常对照组升高 ,其变化呈阴虚热盛组 <气阴两虚组 <气滞血瘀组趋势 ,每两组间具有非常显著性差异 (P <0 0 1)。结论 糖尿病发病以正气不足为内在依据。随着病程的进展 ,脾肾亏虚及血瘀加重是必然趋势。治疗应重视补脾肾和活血化瘀 相似文献
43.
目的 探讨老年牙周组织疾病的证候特点。方法 对 1998 年 1 月-2003 年 12 月门诊接诊的 216 例老年牙周组织疾病进行回顾性分析。结果 阴虚火旺型 124 例(57.4%),气血不足型 51 例(23.6%),胃火炽盛型 16 例(7.5%),气滞血瘀型 14 例(6.4%),痰湿阻络型 11 例(5.1%)。结论 老年牙周组织疾病证候表现以虚为主、虚中夹实,阴虚火旺型和气血不足型是其主要证候类型。 相似文献
44.
Previous work showed that GABAergic differentiation in developing chick retina depends on insulin and cell interactions. Here, we investigated whether it depended on cell signaling mediated by retina cognin, a 50 kDa cell recognition molecule. Cognin mediates cell adhesion in vitro and occurs on retinal neurons that become both GABAergic and cholinergic. We investigated two markers of GABAergic differentiation: glutamate decarboxylase (GAD) activity and high-affinity GABA uptake. Both increase during differentiation of retinal neurons in culture and can be easily measured. We blocked cognin-mediated cell signaling with cognin antibody and found a reduction of the developmental increase in GAD activity in cultures of retinal neurons from 7 and 11 day chick embryos. There was no reduction of high-affinity GABA uptake. This suggested that cognin-mediated signaling was necessary for the normal developmental increase in GAD but not for high-affinity GABA uptake. These results contrasted with our previous observations on cholinergic differentiation in cultured retinal neurons. We found that cognin antibody blocked the normal developmental increase in choline acetyltransferase (ChAT) only if the cells were exposed before embryonic day 7. Thus, while both GAD and ChAT activity appear to be controlled by cell signaling involving cognin, the periods of developmental sensitivity for the two differentiation markers are different. Antibodies to other adhesion molecules, Ng-CAM, and N-cadherin, did not similarly affect GAD activity. Antibodies to laminin at a 10-fold higher concentration inhibited GAD activity only in early embryonic retina. Tests for protein synthesis and “housekeeping” enzyme activity demonstrated that the cognin antibody effect was selective for neuronal differentiation pathways. Thus, GABAergic differentiation in developing retina is sensitive to cell signaling mediated in part by cognin. 相似文献
45.
根据第一作者在马来西亚从事中医临床工作50余年的经验,以中医理论为指导,探讨了在炎热的马来西亚,寒邪致病的可能性、客观性以及寒邪致病的病因、病机、临床表现特征及其治疗方法。 相似文献
46.
DOWN-REGULATION OF C-MYC ONCOGENE DURING NGF-INDUCED DIFFERENTIATION OF NEUROBLASTOMA CELL LINES 总被引:1,自引:0,他引:1
DOWN-REGULATIONOFC-MYCONCOGENEDURINGNGF-INDUCEDDIFFERENTIATIONOFNEUROBLASTOMACELLLINESChenJie(陈杰),LiuTonghua(刘彤华)andAlonzoHRo... 相似文献
47.
突触蛋白-Ⅰ在胚胎干细胞体外神经分化过程中的表达变化 总被引:3,自引:0,他引:3
目的探讨突触蛋白-I(synapsin-I)在胚胎干细胞(ESCs)体外神经分化过程中的表达变化及作用。方法采用“五步法”和维甲酸(RA)法两种途径体外诱导ESCs向神经细胞分化,并以另一种可向神经细胞分化的肿瘤细胞-PC12细胞的诱导过程作参照,从不同的途径、不同的细胞进行比较.通过免疫组织化学、RT-PCR、Western blot方法观察这一过程中synapsin-I的表达变化.找出synapsin-I在ESCs向神经细胞分化过程中表达变化的共同规律。结果结合形态学和其它神经特异性指标的变化,synapsin-I在ESCs和PC12细胞向神经细胞分化的过程中具有早期即有表达,后逐渐升高,至分化成熟阶段达最高,后期又逐渐下降的变化规律。结论在ESCs的分化过程中,synapsin-I的表达存在特定的时空规律,并与ESCs的形态学改变相关,提示synapsin-I可能对ESCs在神经分化过程中的形态分化起着重要的作用。 相似文献
48.
Jong-Kai Hsiao Ming-Fong Tai Hung-Hao Chu Shin-Tai Chen Hung Li Dar-Ming Lai Sung-Tsang Hsieh Jaw-Lin Wang Hon-Man Liu 《Magnetic resonance in medicine》2007,58(4):717-724
The purpose of this work was to evaluate the efficacy of labeling human mesenchymal stem cells (hMSCs) by ionic superparamagnetic iron oxide (SPIO) without a transfection agent and verifying its capability to be detected with clinical 1.5 T magnetic resonance (MR) at the single-cell level. Human hMSCs were incubated for 24 h with an ionic SPIO, Ferucarbotran. The labeling efficiency of hMSCs was determined by iron content measurement spectrophotometrically, and the influence of labeling on cell behavior was ascertained by examination of cell viability using the trypan blue exclusion method, cell proliferation analysis using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, mitochondrial membrane potential (MMP) change, differentiation capacity, and reactive oxygen species (ROS) production measured by dichlorofluorescein diacetate (DCFDA) fluorescent probe. Labeled hMSCs were scanned under 1.5 T MRI with three-dimensional (3D) and two-dimensional (2D) T(2)-weighted gradient echo (GRE) pulse sequences. Human hMSC labeling without transfection agent was efficient. The iron content in hMSCs was 23.4 pg Fe/cell. No significant change was found in viability, proliferation, MMP change, ROS production, or differentiation capacity. About 45.2% of the hMSCs could be detected using 1.5 T MRI at the single cell level with 3D GRE and four repetitions. 相似文献
49.
50.
支气管扩张症辨证模式初探 总被引:4,自引:0,他引:4
目的:探讨支气管扩张症的中医辨证分型规律及证候特点.方法:通过对563例支气管扩张症的临床流行病学调查,采集以症状、体征、舌、脉及相关理化检测为变量的基本信息,以频数分析、聚类分析、方差分析等方法,提炼支气管扩张症的证候分布规律及证候特点.结果:临床上支气管扩张症多见4种证候类型,分别为痰热壅肺证(45.65%)、肝火犯肺证(24.51%)、肺脾气虚证(22.38%)、气阴两虚证(7.46%).结论:较大样本的临床流行病学调查为研究支气管扩张症辨证分型规律提供了科学依据,并可以通过主症判别分析法建立证候识别模式,为临床实践提供依据. 相似文献