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931.
淋巴结血管内T细胞淋巴瘤1例报道及文献复习   总被引:1,自引:0,他引:1  
目的 探讨血管内淋巴瘤 (IVL)的临床病理特征。方法 对 1例腹股沟淋巴结IVL临床、病理组织学及免疫表型进行观察分析并复习文献。结果 男性 31岁 ,不明原因高热伴消瘦 5 0天 ,右腹股沟直径 1cm淋巴结 1枚 ,B超示肝脏轻度增大 ,血LDH明显升高伴ESR及转氨酶轻度升高 ,外周血WBC 3 3× 10 7/L ,骨髓像、多种病原及各肿瘤相关抗原检测均无异常。病理活检 :腹股沟淋巴结大部分破坏 ,代之以大量扩张的中小血管 ,腔内充满大量异型淋巴样细胞 ,局部伴管壁、管周浸润并累及结外脂肪组织。瘤细胞免疫表型CD4 5、CD4 5RO、CD3阳性 ,CK、CD6 8、CD79α、CD2 0均阴性 ,血管壁及内皮细胞CD31、CD34阳性。行CHOP化疗后症状缓解 ,现仍在随访中。结论 IVL是一罕见的非霍奇金淋巴瘤 ,好发于中枢神经系统及皮肤 ,其他部位少见 ,绝大数为B细胞型 ,T型罕见 ,以浅表淋巴结活检确诊者尚无报道。临床表现有一定提示性 ,确诊靠组织病理学检查 ,部分病例对化疗敏感 ,但多数病例预后差  相似文献   
932.
933.
Estrogen and thyroid hormones exert effects on growth, development, and differentiation of the nervous system. Hormone administration can lead to changes in behavior, suggesting that genetic variants of the estrogen receptor alpha (ERalpha) and the thyroid hormone receptor alpha (TRalpha) genes may predispose to psychiatric diseases. To investigate this possibility, regions of likely functional significance (all coding exons and flanking splice junctions) of the ERalpha and TRalpha genes were scanned in patients with schizophrenia (113), along with pilot studies in patients with bipolar illness (BPI), puerperal psychosis, autism, attention-deficit hyperactivity disorder (ADHD), and alcoholism. A total of 1.18 megabases of the ERalpha gene and 1.16 megabases of the TRalpha gene were scanned with Detection of Virtually All Mutations-SSCP (DOVAM-S), a method that detects virtually all mutations. Four missense mutations, seven silent mutations and one deletion were identified in the ERalpha gene, while only four silent mutations were present in the TRalpha gene. Two of the missense mutations in ERalpha are conserved in the six available mammalian and bird species (H6Y, K299R) and a third sequence variant (P146Q) is conserved in mammals, birds, and Xenopus laevis, hinting that these sequence changes will be of functional significance. These changes were found in one patient each with BPI, puerperal psychosis, and alcoholism, respectively. Analysis of the ERalpha and TRalpha genes in 240 subjects reveals that missense changes and splice site variants are uncommon (1.7% and 0%, respectively). Further analyses are necessary to determine if the missense mutations identified in this study are associated with predisposition or outcome for either psychiatric or nonpsychiatric diseases.  相似文献   
934.
未折叠蛋白应答在强直性脊柱炎发病机制中的意义探讨   总被引:5,自引:0,他引:5  
目的:通过研究强直性脊柱炎(AS)病人的外周血单个核细胞(PBMC)关节液单个核细胞(SFMC)的基因谱,了解有无支持UPR假说的转录物以及那些细胞参与未折叠蛋白应答(UPR),UPR在AS病人的变化及其在关节炎发病机制中的作用和意义。方法:AS病人的PBMCSFMC基因表达谱通过含1176基因的cDNA微阵列扫描得到,结果中比较AS与健康自愿者和RA病人有差异表达的基因C2、C3、C8、LMP2、LMP7和BiP(UPR的标志物)再以RTPCR验证。结果:AS患者的SFMC中的BiP表达显著高于RA患者SFMC组(RTPCR的均数和标准差为86.4±111.3和18.5±13.0,两者比较,P=0.044),AS和RA患者SFMC组的C2分别为91.6±36.7和18.5±3.6(两者比较,P<0.037),而且AS患者的SFMC中BiP和UPR相关的蛋白酶体C2的增高水平密切相关(相关系数r=0.9)。另外,研究还发现,AS患者SFMC过度表达BiP的细胞是单核巨噬细胞。结论:内质网UPR确实发生在AS患者SFMC中的巨噬细胞。结果显示UPR应答在AS病人关节炎症的初期和延续中起重要的作用。  相似文献   
935.
目的子研究c—erbB-2在肾细胞癌中的表达及其与临床分期、病理分型、病理分级和预后的关系。方法 应用免疫组化S-P法分别用鼠抗人c-erbB-2胞内段单克隆抗体(CB11)和鼠抗人c-erbB-2胞外段单克隆抗体(9G6.10)检测77例肾细胞癌及相应癌旁肾组织c—erbB-2蛋白表达。应用RT-PCR方法检测10例新鲜肾癌组织及癌旁正常组织c—erbB-2 mRNA的表达。透明细胞癌、颗粒细胞癌及乳头状肾细胞癌c—erbB-2的表达分别为68.2%、93.1%及75.0%。结果 77例肾癌组织CB11和9G6.10的阳性率分别为61%(47/77)和45.5%(35/77);二者联合检测总阳性率为77.9%(60/77)。透明细胞癌、颗粒细胞癌及乳头状肾细胞癌c—erbB-2的表达分别为68.9%、92.9%及75%。RT-PCR检测新鲜肾癌组织c—erbB-2mRNA的阳性率为100%(10/10)。结论 肾癌中c—erbB-2蛋白及c—erbB-2mRNA均过表达。不同的肾癌病理类型c—erbB-2蛋白表达不同,颗粒细胞癌表达最高。c—erbB-2在肾癌的不同临床分期均过表达,说明可能在病变的早期c—erbB-2已经发生改变。c-erbB-2的表达与临床分期及肿瘤分级无明显相关性。  相似文献   
936.
用离体血管灌流实验验证冯元桢等关于血管内皮细胞的膜张应力逆血流方向累加的理论分析.长度分别为11、21 cm的离体血管段内皮细胞分别置于平均切应力均为0.12 N/m2的脉动流环境中剪切42 h.11 cm处理的内皮素-1(ET-1)平均分泌速率(16.93±0.89 pg/cm2*h)显著低于21 cm处理(26.13±1.79 pg/cm2*h), 差异比率为1∶1.5.脉动流作用引起的ET-1平均分泌率显著高于定常流的作用. 总体上表明在脉动流条件下,血管段长度与其血管内皮细胞ET-1代谢(分泌量)间有密切的相关关系.本实验结果从又一个侧面证实血管内皮细胞膜张应力存在累加效应.  相似文献   
937.
Using functional magnetic resonance imaging (fMRI), we explored the binocular interactions occurring when subjects viewed dichoptically presented checkerboard stimuli. A flickering radial checkerboard was presented to each eye of the subject, while T2*-weighted images were acquired over the visual cortex with gradient-echo, echoplanar sequences. We compared responses in striate and extrastriate visual cortex under four conditions: both eyes were stimulated at the same time (binocular condition), each eye was stimulated in alternation (monocular condition) or first the one eye then the other eye was stimulated (left eye first - right eye trailing, or vice versa). The results indicate that only the striate area, in and near the calcarine fissure, shows significant differences for these stimulation conditions. These differences are not evident in more remote extrastriate or associational visual areas, although the BOLD response in the stimulation-rest comparison was robust. These results suggest that the effect could be related to inhibitory interactions across ocular dominance columns in striate visual cortex.  相似文献   
938.
Dopamine transporter (DAT) gene is implicated in the pathogenesis of attention deficit hyperactivity disorder (ADHD). Previously a meta-analysis concluded no association between the variable-number-of-tandem-repeats (VNTR) polymorphisms of the DAT gene and ADHD. However, significant heterogeneity was present among studies and no conclusion can be drawn about the association in any single ethnicity given the small number of studies. There were also conflicting results in Chinese populations. We therefore perform the present study to investigate the association in Chinese children in Hong Kong. In this prospective family-based and case-control study during January to June 2004, we recruited consecutive Chinese children diagnosed with ADHD by DSM-IV criteria, their family members, and sex-matched controls admitted for acute upper respiratory infection, excluding those with perinatal brain insults, mental retardation, or neurological deficits. VNTR polymorphisms of the DAT gene were determined by standard PCR followed by agarose gel electrophoresis. Sixty-four ADHD cases (52 boys, 12 girls), their family members and 64 normal controls were recruited. The 10-repeat allele (92.6%) and the 10/10 repeat genotype (85.2%) were the most prevalent. Both family-based and case-control analyses showed no association between the DAT gene polymorphisms and ADHD (transmission dysequilibrium test: P = 0.99; odds ratio of 10-repeat allele = 0.89 (95%CI 0.35-2.28), P = 0.81; odds ratio of 10/10 repeat genotype = 0.69 (95%CI 0.26-1.84), P = 0.46). We concluded that VNTR polymorphism of the DAT gene is not associated with ADHD in Chinese children, and further studies are needed to clarify the polygenic and environmental influences for pathogenesis of ADHD.  相似文献   
939.
目的 :研究突变型p2 7基因 (p2 7mt)对肝癌细胞生长的影响。方法 :采用重组腺病毒载体Ad p2 7mt将p2 7mt全长cDNA转入到肝癌细胞系SMMC 772 1中。3H TdR掺入法及软琼脂集落形成实验检测p2 7mt对肝癌细胞增殖的作用。结果 :转染p2 7mt基因的SMMC 772 1细胞在蛋白质水平有高水平的基因表达。其3H TdR掺入量及集落形成率明显低于对照组 (P <0 .0 5)。结论 :p2 7mt基因能抑制肝癌细胞增殖。p2 7mt可作为目的基因用于基因治疗。  相似文献   
940.
Abstract

Monitoring people’s stress levels has become an essential part of behavioural studies for physical and mental illnesses conducted within the biopsychosocial framework. There have been several stress assessment studies in laboratory-based controlled settings. However, the results of these studies do not always translate effectively to an everyday context. The current state of wearable sensor technology allows us to develop systems measuring the physiological signals reflecting stress 24/7 while capturing the context. In this paper, we present a stress monitoring system that provides objective daily stress measurements in everyday settings based on three physiological signals: electrocardiogram (ECG), photoplethysmogram (PPG), and galvanic skin response (GSR) using Shimmer3 ECG, Shimmer3 GSR+, and Empatica E4 wearable sensors. We perform controlled stress assessment experiments on 17 participants in which we successfully detect stress with a 94.55% accuracy for 10-fold cross-validation and an 85.71% accuracy for subject-wise cross-validation. In everyday settings, the system assesses stress with an 81.82% accuracy. We also examine whether motion artefacts affect stress assessment and filter the low-confidence readings to minimise false alarms.  相似文献   
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