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91.
92.
目的探讨基于肾脏CT平扫图像纹理分析的影像组学模型在预测肾透明细胞癌(ccRCC)WHO/国际泌尿病理学会(ISUP)病理分级中的价值。方法回顾性分析2016年12月至2019年5月中国科学院大学附属肿瘤医院经手术病理证实且有明确病理分级的90例ccRCC患者,按照7∶3的比例将所有患者随机分为训练组(63例)及测试组(27例)。根据2016版WHO/ISUP分级标准,将Ⅰ、Ⅱ级归为低级别组(53例),Ⅲ、Ⅳ级归为高级别组(37例)。在CT平扫图像上逐层勾画肿瘤ROI,提取93个纹理特征,利用最小绝对收缩与选择算子(LASSO)回归对特征参数进行降维,并建立影像组学评分(Rad-score)。以病理分级结果为金标准,采用logistic回归构建ccRCC病理分级的预测模型。采用ROC曲线及校准曲线评价模型的诊断效能,计算曲线下面积(AUC)、敏感度、特异度和准确度。采用Hosmer-Lemeshow拟合优度检验评价模型的校准度。结果经降维和交叉验证后筛选出10个非零系数的纹理特征,根据这10个特征及其对应系数的线性加权形成预测ccRCC新病理分级的影像组学风险评分,并建立预测模型。该模型在训练组中的AUC值为0.933(95%CI 0.862~1.000),其判断WHO/ISUP分级高级别ccRCC的灵敏度为92.3%,特异度为89.2%,准确度为90.5%,校准曲线显示该模型的校准度较好(P=0.257)。在测试组中的AUC值为0.875(95%CI 0.734~1.000),灵敏度为72.7%,特异度为87.5%,准确度为81.5%,校准曲线显示该模型的校准度较好(P=0.125)。结论基于平扫CT纹理分析构建的影像组学预测模型对ccRCC WHO/ISUP病理分级的评估具有应用潜能。 相似文献
93.
Aysen Terzi Isıl Yıldız Aktaş Anıl Dolgun Ali Ayhan Türkan Küçükali Alp Usubütün 《Pathology, research and practice》2013
We intended to reevaluate the morphologic prognostic factors for early-stage ovarian carcinomas. We reviewed 111 patients diagnosed with early-stage ovarian cancer who had undergone primary surgery at Hacettepe Hospital between 1984 and 2001, using diagnostic criteria from the WHO-2003 classification. We applied the Universal grading system suggested by Shimizu/Silverberg and noted FIGO-stage, histotype, tumor size, bilaterality, and endometriosis. These features were compared with each other and survival. The survival analysis was carried out by Kaplan–Meier curves. Of the cases, 52 were reclassified as ‘borderline tumor’ or ‘cystadenoma with borderline foci’ and 59 as ‘invasive carcinoma’. FIGO-stage and mitotic count were significant for survivals of 59 patients with cancer. Mitotic index was also significant for the probability of metastasis. The patients with stage-II cancer had 5.65 times more risk of recurrence than stage-I cancer. The 5-year overall and disease-free survivals rates were 90.6% and 87.5% for stage-I, 54.7% and 39.3% for stage-II, respectively. Universal grade did not reach statistical significance for survivals but it was related to FIGO-stage significantly. In conclusion, FIGO-stage is the most reliable prognosticator. Although prognostic value of universal grade is not significant, mitotic count may provide important prognostic information for early-stage ovarian carcinomas. 相似文献
94.
《Immunological investigations》2013,42(3):235-244
The etiology of Systemic lupus erythematosus (SLE) seems to be multifactorial including environmental as well as genetic factors. Major histocompatibility complex (MHC) genes especially HLA-DRB1 and HLA-DQB1 are strongly implicated in susceptibility to SLE. Moreover ethnicity has been found to have a significant role in both disease susceptibility and disease expression. This study was carried out to determine HLA-DRB1 allele association with SLE susceptibility and disease presentation in Egyptian children with juvenile onset SLE. HLA-DRB1 allele typing was done using polymerase chain reaction-sequence-specific oligonucleotide probe for 65 juvenile Egyptian SLE patients and 150 healthy controls. p-values were corrected for the number of the alleles tested (Pc). HLA-DRB1*15 g allele was significantly increased in SLE children versus controls (OR = 4.76; 95% CI = 1.83–12.4; p = 0.001 and Pc = 0.012). No HLA-DRB1 allele was found to be statistically significant associated with musculoskeletal, cutaneous, hematologic, cardiac or neuropsychiatric manifestations in SLE patients (p > 0.05). Moreover no statistically significant association was found between HLA-DRB1 alleles and clinical presentation or histologic classes of lupus nephritis. The current work suggests that HLA-DRB1*15g allele may be a susceptibility allele in Egyptian children with SLE but is not related to clinical presentation of SLE. 相似文献
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98.
Sang Hwa Lee Hyunkyung Kim Wook Youn Kim Hye Seung Han So Dug Lim Wan Seop Kim Sehun Kim Tae Sook Hwang 《Pathology international》2013,63(5):252-259
We evaluated p53, KRAS, BRAF and CTNNB1 mutation and p53, WT1, p16 and beta‐catenin expression in 31 ovarian high‐grade serous adenocarcinoma. Twenty‐five (80.6%) tumors contained functional mutations of p53; three frameshift, four nonsense and 19 missense mutations. None of the tumors showed KRAS, BRAF or CTNNB1 mutation. In all 18 tumors with missense mutations, ≥60% of tumor cells were strongly positive for p53 immunostaining whereas all tumors with frameshift or nonsense mutations were completely negative. Missense mutation was correlated with diffuse and strong imunoreaction and frameshift/nonsense mutation was correlated with completely negative immunoreaction (P = 0.000). Tumors with wild‐type p53 revealed a wide range of immunostaining patterns. In 27 (87.1%) and 18 (58.1%) tumors, ≥50% of tumor cells were moderate to strongly positive for WT1 and p16, respectively. A considerable intratumoral heterogeneity for p16 expression was present. None of the tumors demonstrated nuclear beta‐catenin expression. p53 mutations appear to be a powerful molecular marker for ovarian high‐grade serous adenocarcinoma. Using p53 with an appropriate interpretation criteria together with WT1, p16 and beta‐catenin, most of the high‐grade serous adenocarcinoma could be distinguished from other ovarian tumors. 相似文献
99.
目的:探究基于GRACE评分系统的临床分级护理在急性冠状动脉综合征(ACS)胸痛病人中的应用效果。方法:选取2017年12月—2019年12月医院就诊的70例ACS胸痛病人为研究对象,随机分为观察组与对照组各35例。对照组实施常规护理,观察组实施基于GRACE评分系统的临床分级护理。比较两组病人不良心血管事件(MACE)、死亡情况以及护理质量状况。结果:观察组病人MACE总发生率及病死率明显低于对照组(P<0.05);观察组病人直接护理时间明显长于对照组,分级护理合格率、护理措施到位率明显高于对照组,住院时间明显短于对照组(P<0.05)。结论:基于GRACE评分系统的临床分级护理应用于ACS胸痛病人中,可明显减少MACE发生风险,降低病死率,提高护理质量。 相似文献
100.
目的:调查河北省急性缺血性脑卒中患者的院内诊治时间分布情况。方法:收集并分析河北省急性缺血性脑卒中患者的院内诊治流程资料并与NINDS推荐时间进行比较。结果:院内诊治中位时间104 min高于推荐的60 min(
P<0.001);"完成头颅CT扫描-获取CT报告"中位时间30 min高于推荐的20 min(
P<0.001);"获取头颅CT报告-开始治疗"中位时间43 min高于推荐的15 min(
P<0.001)。通过EMS就诊患者院内诊治中位时间是101 min,低于未采用患者的104 min(
P=0.01);三级医院院内诊治中位时间是105 min,迟于二级医院的99 min (
P<0.05)。
结论:河北省急性缺血性脑卒中院内救治延迟现象严重。获取头颅CT报告到开始溶栓治疗这一环节是造成院内延迟的最主要环节。通过EMS就诊可以缩短院内救治时间;二级医院相比三级医院院内延迟情况较轻。 相似文献