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991.
目的研究小肝癌(SHCC)在l6层螺旋CT(SCT)多期(动脉期、门脉期和延迟期)增强扫描的表现特征。方法对本院经病理证实的56例小肝癌患者的影像学资料进行回顾性分析。结果患者动脉期的病灶数要明显高于门静脉期和延迟期,差异有统计学意义(P〈0.01),动脉期的敏感性高于门脉期和延迟期。小肝癌总的病灶栓出率为94.6%(53/56),动脉期、门静脉期和延迟期的病灶检出率分别为87.5%(49/56)、69.6%(39/56)和60.7%(34/56)。结论多层螺旋CT多期增强扫描能够充分反映出小肝癌的血供特点和表现,能够实现早期诊断。 相似文献
992.
目的探讨食管癌医学影像检查术前诊断价值。方法对本院2009年6月~2011年6月36例经病理证实的食管癌患者术前钡餐和CT表现与手术后病理结果进行比较。结果36例患者中按照Moss分期标准Ⅰ期1例,Ⅱ期5例,Ⅲ期21例,Ⅳ期9例。结论应用钡餐与CT检查可提高食管癌患者的检出率,有助于手术方式的选择及术前分期的确定。 相似文献
993.
目的探讨湖北地区汉族女性人群中p53基因第72位密码子基因多态性与HPV16相关宫颈癌发生的关系。方法随机选取经PCR检测证实HPV16阳性的宫颈病变病例228例。其中病理证实为宫颈浸润癌的156例作为宫颈癌组,宫颈上皮内瘤变或宫颈炎72例为对照组。用直接PCR法检测新鲜组织标本中p53基因第72位密码子的基因型在宫颈癌组与对照组的分布情况,分析p53codon72基因多态性与HPV16阳性宫颈癌之间的相关性。结果所有样本均成功检测出p53codon72基因型。Pro/Pro、Arg/Pro、Arg/Arg在HPV阳性宫颈癌样本中所占比例分别为22.2%、47.2%、30.6%;在对照组中的比例分别为32.7%、53.2%、14.1%。两组总构成比差异有统计学意义(P=0.010)。与其他两种基因型相比,p53codon72Arg/Arg基因型在HPV16阳性宫颈癌样本检出率明显高于在HPV16阳性宫颈上皮内瘤变及宫颈炎组中的检出率(P=0.004,OR=2.680)。结论p53codon72Arg/Arg基因型是湖北地区汉族女性发生HPV16相关宫颈癌的遗传易感因素。 相似文献
994.
目的分析信阳市手足口病实验室检测结果,掌握手足口病流行趋势,为本地区手足口病的综合防治提供参考资料。方法采集临床880份诊断为手足口病病例的咽拭子、粪便和肛拭子、疱疹液,应用real time RT-PCR技术检测肠道病毒71型(EV71)、柯萨奇病毒A组16型(CA16)、通用型肠道病毒(EV)。结果 880份检测标本中,肠道病毒总体检出率为74.32%,其中肠道病毒EV71型、CA16型和其它肠道病毒阳性检出率分别为34.66%、17.27%和20.11%。不同病毒阳性检出率差异有统计学意义(χ2=307.45,P<0.01)。880份检测标本中,从发病至采样0~3d病毒核酸检测率最高(83.54%),其次是4~7d(76.87%)。咽拭子、粪便、肛拭和疱疹液阳性率分别为8.33%、78.01%、66.15%和75%。粪便与其它样本的阳性检出率差异有统计学意义(χ2=27.05,P<0.01)。病例发病集中在4~7月份,以EV71感染为主,病毒感染率以<1岁组最高,男女病毒感染率差异无统计学意义(χ2=0.12,P=0.73)。结论信阳市手足口病的病原体主要是EV71,其流行具有明显的年龄、季节界限。 相似文献
995.
996.
目的宫颈上皮内瘤变(cervical intraepithelial neoplasias,CIN)是一组与宫颈浸润癌密切相关的癌前期病变的统称,包括宫颈不典型增生和宫颈原位癌,反映了宫颈癌发生中连续发展的过程,本研究探讨吸烟及HPV16/18感染与宫颈上皮内瘤变自然消退之间的关系。方法追踪2009年1月~2010年12月在长沙市三医院及长沙市妇幼保健院确诊为宫颈上皮内瘤变Ⅰ、Ⅱ期患者并在1年后复检者共385例,其中吸烟者98例,不吸烟者287例,高危HPV16/18感染者242例,无高危HPV16/18感染者143例。1年后复检385例患者中166例宫颈上皮内瘤变自然消退。对HPV16/18及吸烟对宫颈上皮瘤变转归的关系进行统计学分析。结果一年后385例CIN中166自然消退,非HPV16/18感染患者较HPV16/18感染患者有更高的宫颈上皮内瘤变自然消退率(60.8%vs32.6%),而其中吸烟的HPV16/18感染者宫颈上皮内瘤变自然消退率最低(27.1%)。结论Ⅰ、Ⅱ期宫颈上皮内瘤变在12月内可自然消退,HPV感染(HPV16/18)是宫颈上皮内瘤变持续的重要因素,吸烟可能促进HPV感染患者宫颈上皮内瘤变的持续存在。 相似文献
997.
Stenner M Yosef B Huebbers CU Preuss SF Dienes HP Speel EJ Odenthal M Klussmann JP 《Histopathology》2011,58(7):1117-1126
Stenner M, Yosef B, Huebbers C U, Preuss S F, Dienes H‐P, Speel E‐J M, Odenthal M & Klussmann J P (2011) Histopathology 58 , 1117–1126 Nuclear translocation of β‐catenin and decreased expression of epithelial cadherin in human papillomavirus‐positive tonsillar cancer: an early event in human papillomavirus‐related tumour progression? Aims: High‐risk human papillomaviruses (HPVs) constitute an important risk factor for tonsillar cancer. This study describes changes in cell adhesion molecules during metastasis of HPV‐related and HPV‐unrelated tonsillar carcinomas. Methods and results: We examined 48 primary tonsillar carcinoma samples (25 HPV‐16 DNA‐positive, 23 HPV‐16 DNA‐negative) and their respective lymph node metastases for their HPV status and for the expression of p16, epithelial cadherin (E‐cadherin), β‐catenin, and vimentin. A positive HPV‐specific polymerase chain reaction finding correlated significantly with p16 overexpression in both primary tumours and their metastases (P < 0.0001 for both). In HPV‐unrelated carcinomas, the expression of E‐cadherin was significantly lower in metastases than in primary tumours (P < 0.001). In contrast, the expression of nuclear β‐catenin was significantly higher in metastases than in primary tumours (P = 0.016). In HPV‐related carcinomas, nuclear localization of β‐catenin expression was already apparent in primary tumours (P = 0.030). The expression of vimentin significantly correlated with the grading of the primary tumour (P = 0.021). Conclusions: Our data indicate that the down‐regulation of E‐cadherin and the up‐regulation of nuclear β‐catenin expression might be crucial steps during tumour progression of tonsillar carcinomas, being already present in primary tumours in HPV‐driven carcinomas, but becoming apparent in HPV‐unrelated tumours later in the process of metastasis. 相似文献
998.
Chae SW Sohn JH Kim DH Choi YJ Park YL Kim K Cho YH Pyo JS Kim JH 《Yonsei medical journal》2011,52(3):445-453
Purpose
The molecular mechanisms that are responsible for the initiation and progression of breast cancers are largely unknown. This study was to analyze the cyclin B1, cdc2, p53 and p16 tumor suppressor genes in human breast cancer.Materials and Methods
To investigate the role of cyclin B1, cdc2, p53 and p16 in the pathogenesis and progression of breast carcinomas, 98 cases of breast cancers were examined by immunohistochemical method. The correlations of cyclin B1, cdc2, p53 and p16 expression with various clinico-pathologic findings were analysed.Results
In the normal breast tissues, cyclin B1, cdc2 and p16 were weakly expressed, while p53 was not expressed. On the other hand, cyclin B1, cdc2, p53 and p16 were overexpressed in breast cancer, showing correlation between the expression of cyclin B1 and cdc2 and breast cancers (p=0.00). The overexpressions of cdc2 and p16 were correlated with an infiltrative tumor border pattern and this was statistically significant (p<0.05). In addition, the overexpression of cdc2 was correlated with histologic high grade carcinomas (p=0.00).Conclusion
Cyclin B1 and cdc2 appeared to be involved in the genesis or progression of breast cancers. In addition, the overexpressions of p16 and p53 may play important roles in more aggressive tumor and the overexpression of cdc2 is associated with progression of tumor to a higher grade of breast carcinomas. The deranged overexpressions of cyclin B1, cdc2, p16 and p53 may play an important role in human breast carcinogenesis. 相似文献999.
1000.
Endophytic bacterial diversity in roots of Typha angustifolia L. in the constructed Beijing Cuihu Wetland (China) 总被引:1,自引:0,他引:1
We investigated the community structure of endophytic bacteria in narrowleaf cattail (Typha angustifolia L.) roots growing in the Beijing Cuihu Wetland, China, using the 16S rDNA library technique. In total, 184 individual sequences were used to assess the diversity of endophytic bacteria. Phylogenetic analysis revealed that 161 clones (87.5%) were affiliated with Proteobacteria, other clones grouped into Cytophaga/Flexibacter/Bacteroids (3.3%), Fusobacteria (3.8%), and nearly 5% were uncultured bacteria. In Proteobacteria, the beta and gamma subgroups were the most abundant, accounting for approximately 46% and 36.6% of all Proteobacteria, respectively. The dominant genera included Rhodoferax, Pelomonas, Uliginosibacterium, Pseudomonas, Aeromonas, Rhizobium, Sulfurospirillum, Ilyobacter and Bacteroides. While some of these endophytic bacteria are capable of fixing nitrogen and can therefore improve plant growth, other endophytes may play important biological roles by removing nitrogen, phosphorus and/or organic matter from the water body and thus have the potential to enhance the phytoremediation of eutrophic water bodies. These bacteria have the potential to degrade xenobiota such as methane, methanol, methylated amines, catechol, oxochlorate, urea, cyanide, and 2,4-dichlorophenol. Hence, the use of certain endophytic bacteria in the process of phytoremediation could be a powerful approach for the restoration of eutrophic systems. 相似文献