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101.
目的 检测肺鳞状细胞癌中死亡相关蛋白激酶 (DAP K)mRNA表达及细胞凋亡 ,探讨DAP K与细胞凋亡的关系及其在肺鳞状细胞癌发生、发展中的作用。方法 用原位分子杂交法检测 6 0例肺鳞状细胞癌、9例癌旁肺组织DAP KmRNA表达 ;用原位末端标记TUNEL法检测相应组织中细胞凋亡 ,计算凋亡指数 (AI)。结果 肺鳞状细胞癌的DAP KmRNA阳性表达率为 4 6 7% ,癌旁肺组织为 6 7 7% ,其阳性率高于肿瘤组织 (P <0 0 1 )。在肺鳞状细胞癌中 ,高分化癌DAP KmRNA阳性率为 70 % ,低分化癌为 2 3 3% ,高分化癌的DAP KmRNA阳性率高于低分化癌 (P <0 0 1 )。肺鳞状细胞癌的细胞AI为(0 6 72 8± 0 4 2 6 1 ) % ,癌旁肺组织中支气管肺泡上皮细胞AI为 (1 0 2 89± 0 2 4 33) % ,癌旁肺组织的AI高于肿瘤组织 (P<0 0 1 )。在肺鳞状细胞癌中 ,高分化癌的AI为 (0 5 82 3± 0 1 92 2 ) % ,低分化癌为 (0 4 4 6 0± 0 1 92 5 ) % ,高分化癌的AI高于低分化癌 (P <0 0 1 )。DAP KmRNA呈阳性表达的肺癌 ,其AI为 (0 5 31 7± 0 2 0 97) % ;DAP KmRNA呈阴性者 ,其AI为 (0 4 872± 0 1 91 8) % ,两组间差异有显著性 (P <0 0 5 )。在连续切片上 ,DAP KmRNA阳性细胞的分布区域与凋亡阳性细胞的分布相似。DAP KmRNA呈阳性表达 相似文献
102.
103.
目的:探讨新生儿脐血中胰岛素样生长因子-Ⅰ(IGF-Ⅰ)和胰岛素样生长因子结合蛋白-3(IGFBP-3)水平与胎儿宫内生长发育的关系.方法:采用放射免疫分析,分别对出生时体重正常新生儿与宫内生长迟缓的低体重新生儿脐血的IGF-Ⅰ及IGFBP-3水平进行检测.结果:宫内发育迟缓组新生儿脐血的IGF-Ⅰ及IGFBP-3的含量明显低于正常对照组(P<0.01),有显著差异性.结论::IGF-Ⅰ和IGFBP-3与胎儿宫内生长发育密切相关,对胎儿的宫内生长发育起着重要的调节作用. 相似文献
104.
目的:探讨血清睾酮(T)和脂蛋白(a)[Lipoprotein(a),LP(a)]测定对男性冠心病患者的诊疗价值。方法:对102例疑似冠心病(CHD)的男性患者进行冠状动脉造影检查,根据造影结果分为(CHD)病组和非(CHD)组,分别采用放射免疫分析和免疫透射比浊法进行血清T和LP(a)的测定,并对结果进行分析。结果:男性CHD患者血清T水平明显低于非CHD组(P〈0.01),而血清LP(a)水平则显著高于非CHD组,两者之间呈负相关。结论:检测血清T和LP(a)对男性CHD患者的辅助诊断、疗效观察和预后判断具有重要价值。 相似文献
105.
目的探讨重点理工科学校大一新生焦虑状况及相关因素,为进行针对性的干预提供依据。方法以广东某重点理工高校2007级的大一学生为研究对象,采用自行设计一般项目调查表、状态-特质焦虑量表(STAI)、匹兹堡睡眠质量指数量表(PSQI)、应付方式问卷进行测评。结果测查学生不论男女状态焦虑、特质焦虑分均显著高于地方常模;19.29%的学生睡眠质量较差;高状态焦虑组和高特质焦虑组解决问题、求助应付因子分均显著低于低状态焦虑组和低特质焦虑组,而自责、幻想、退避应付因子分则显著高于低状态焦虑组和低特质焦虑组;多元逐步回归分析说明,学生如常采用解决问题应付方式,在一定程度上可避免焦虑的产生,而睡眠质量差、采用自责应对方式则可加重焦虑水平。结论采取有效的认知应对策略其意义是使学生改变应激源,以使其变得威胁较小或变成挑战,把情绪基调训练成兴奋、期待和征服。 相似文献
106.
Rosiglitazone, an agonist of peroxisome proliferator-activated receptor γ, reduces pulmonary inflammatory response in a rat model of endotoxemia 总被引:3,自引:0,他引:3
Objective: The effect of rosiglitazone, a potent peroxisome proliferator-activated receptor γ (PPAR-γ) agonist, on pulmonary inflammation
in endotoxemia was investigated.
Materials and methods: Male Wistar rats were given either lipopolysaccharide (LPS, 6 mg/kg i.v.) or saline, pretreated with rosiglitazone (0.3 mg/kg
i.v.) or its vehicle (dimethyl sulphoxide) 30 min before LPS. The selective PPAR-γ antagonist GW9662 (0.3 mg/kg i.v.) was
given 20 min before rosiglitazone. Wet/dry weight (W/D) ratio, myeloperoxidase (MPO) activity, malondialdehyde (MDA) as well
as TNF-α and CINC-1 concentrations were measured in lung tissues 4 h after LPS injection. Expression of ICAM-1, NF-κB p65
and PPAR-γ were also determined by immunohistochemistry or Western blot analysis.
Results: Rosiglitazone pretreatment significantly attenuated the increases in W/D ratio, MPO activity and MDA levels, and reduced
pulmonary overproduction of TNF-α and CINC-1 as well as expression of ICAM-1 following endotoxemia. Rosiglitazone also inhibited
the nuclear localization of NF-κB and up-regulated the expression of PPAR-γ protein. The specific PPAR-γ antagonist GW9662
abolished the effect of rosiglitazone.
Conclusion: These findings suggest that PPAR-γ agonists might be used as therapeutic agents in the therapy of inflammatory lung injury
related to endotoxemia.
Received 8 January 2005; returned for revision 6 July 2005; returned for final revision 20 July 2005; accepted by M. Katori
31 July 2005 相似文献
107.
PTEN基因对人肝癌细胞系HHCC作用的研究 总被引:4,自引:1,他引:4
目的:研究PTEN基因对人肝癌细胞系HHCC细胞恶性表型及凋亡的影响。方法:将PTEN真核表达载体pBabe-PuroPTEN及空质粒pBabe-Puro,通过脂质体介导的基因转染方法,转入该基因表达缺失的HHCC细胞系中,嘌呤霉素筛选获得稳定表达PTEN基因的转染细胞。通过平板克隆形成试验、DNA凝胶电泳、相差显微镜和电镜,观察PTEN基因对人肝癌细胞系HHCC恶性表型及凋亡的影响。结果:转染后的细胞,经原位杂交、免疫组织化学检测证实,有PTEN mRNA及其蛋白的表达;平板克隆形成试验证实,转染PTEN基因后,细胞形成克隆的能力降低;转染PTEN的细胞在相差显微镜和电镜下可出现典型的凋亡形态学改变;DNA琼脂糖凝胶电泳呈现出明显的梯状条带。结论:外源性PTEN基因导入HHCC细胞后,可降低HHCC的细胞的恶性表型,并促进凋亡发生。 相似文献
108.
Hypoxia can contribute to the induction of the Epstein-Barr virus (EBV) lytic cycle. 总被引:1,自引:0,他引:1
Ju-Hong Jiang Na Wang Ang Li Wen-Ting Liao Zhi-Gang Pan Shi-Juan Mai Da-Jiang Li Mu-Sheng Zeng Jian-Ming Wen Yi-Xin Zeng 《Journal of clinical virology》2006,37(2):98-103
BACKGROUND: Like other herpes viruses, latent Epstein-Barr virus (EBV) infection can be reactivated to lytic replication. Reactivation can be achieved by treatment with various reagents, including tetradecanoyl phorbol acetate (TPA) and Ca2+ ionophores. Relatively little is known about the physiological factors related to reactivation of EBV. Previous studies have demonstrated that G0/G1 cell cycle arrest is associated with EBV activation, and that hypoxic conditions can induce cell cycle arrest. In the present study we investigated the effect of hypoxia on reactivation of EBV. OBJECTIVE AND METHODS: Hypoxic culture conditions were established and the expression of Zta protein and the number of EBV DNA copies were measured in B95-8 cells maintained under these conditions. RESULTS: Hypoxia treatment not only increased the expression of the EBV immediate-early protein Zta (which mediates the switch between the latent and lytic form of infection), but also increased the number of EBV DNA copies in B95-8 cells. CONCLUSIONS: EBV in latent infection can be activated to lytic infection by hypoxia treatment. 相似文献
109.
High-level expression of EphA2 receptor tyrosine kinase in prostatic intraepithelial neoplasia 总被引:11,自引:0,他引:11 下载免费PDF全文
Zeng G Hu Z Kinch MS Pan CX Flockhart DA Kao C Gardner TA Zhang S Li L Baldridge LA Koch MO Ulbright TM Eble JN Cheng L 《The American journal of pathology》2003,163(6):2271-2276
EphA2 is a transmembrane receptor tyrosine kinase that is overexpressed in many carcinomas. Specific targeting of EphA2 with monoclonal antibodies is sufficient to inhibit the growth, migration and invasiveness of aggressive cancers in animal models. Using immunohistochemical analyses, we measured the expression of EphA2 in prostatic adenocarcinoma, high-grade prostatic intraepithelial neoplasia, and adjacent benign prostate tissue from ninety-three radical prostatectomy specimens. These results were related to multiple clinical and pathologicalcharacteristics. The fraction of cells staining positively with EphA2 in benign prostatic epithelium (mean, 12%) was significantly lower than that in high-grade prostatic intraepithelial neoplasia (mean, 67%, P < 0.001) and prostatic adenocarcinoma (mean, 85%, P < 0.001). Moreover, the intensity of EphA2 immunoreactivity in prostatic adenocarcinoma was significantly higher than in benign prostatic tissue (P < 0.001) or high-grade prostatic intraepithelial neoplasia (P < 0.001). Benign prostatic epithelium showed weak or no immunoreactivity for EphA2 in all cases examined. Whereas EphA2 immunoreactivity related to neoplastic transformation, it did not correlate with other clinical and pathological parameters examined. Our data suggest that EphA2 levels increase as prostatic epithelial cells progress toward a more aggressive phenotype. Progressively higher levels of EphA2 in high-grade prostatic intraepithelial neoplasia and prostatic carcinoma are consistent with recent evidence that EphA2 functions as a powerful oncogene. Moreover, the presence of high levels of EphA2 in these cells suggests opportunities for prostate cancer prevention and treatment. 相似文献
110.
Chen YN Chen SY Zeng LJ Ran JM Xie B Wu MY Wu YZ 《British journal of biomedical science》2003,60(1):9-13
Sulphonylurea (SU) stimulates insulin secretion by pancreatic beta-cells and is generally used as a first-line treatment for type 2 diabetes. However, after long-term SU treatment (six months or over), some patients begin to show an increase in blood glucose once again (secondary SU failure). Two theories have been put forward to explain this failure--dysfunction of the proinsulin conversion machinery or insulin resistance. However, the primary pathogenesis behind secondary SU failure still needs to be investigated. Using a reliable technique that specifically identifies intact proinsulin (IPI), total proinsulin (TPI) and specific insulin (SI), this study aims to discover if a defect in the proinsulin converting mechanism plays a role in SU failure. Three groups were recruited for this study: healthy controls (n=8), SU responders (n=38) and secondary SU failures (n= 46). Serum concentrations of insulin-related molecules released in response to a standard glucose challenge test were compared between the groups. It was found that total SI was lower in the patient groups (P<0.05 compared to the control group), while TPI and IPI showed no distinct difference between the three groups (P>0.05). TPI:SI ratio and IPI:SI ratio showed marked increases in the patient groups (P<0.05 compared to control group), with no obvious quantitative difference between SU responders and secondary SU failures (P>0.05). Similar results for the Homa Insulin Resistant Index were found between the two patient groups. Interestingly, blood glucose at 180 mins after glucose challenge was significantly higher in the secondary SU failure group (P<0.05), with no correlation to SI, while the SU responder group showed good correlation between the parameters (P<0.05). We conclude that type 2 diabetes is associated with obvious dysfunction in the proinsulin-converting process and shows severe SI deficiency in responding to glucose challenge. Dysfunction of the proinsulin conversion mechanism was not an extra cause responsible for SU failure. 相似文献