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71.
针对目前的肺结节检测中存在的个体差异、同病异影、同影异病的问题,提出一种大样本条件下的基于Faster-RCNN的肺结节检测算法,对比研究目前的深度学习模型的适应性,给出一种通用的随着样本数量增加肺结节检测率持续提升的策略。首先搭建深度学习的软硬件环境,设置影像数据接口与Faster-RCNN的网络接口匹配;然后搭建Faster-RCNN的单类分类网络,并对网络结构的参数进行调整优化;最后用包含2 000例病人的肺结节数据集,通过不同的卷积神经网络模型 (包括ZF和VGG),计算CT图像在各自模型中的特征。对测试结果进行分析评估,分别统计其漏检率、检测准确率,并探讨不同训练数量和数据增广类型对最终检测准确率的影响。最终ZF模型的检测准确率为90.82%,准确率的波动方差为13.30%;VGG模型的检测准确率为87.02%,准确率的波动方差为37.10%。ZF模型的波动方差小,检测精确度高,综合考虑,ZF模型对肺结节的检测效果优于VGG模型的检出效果。所提出的肺结节检测技术具有良好的理论价值和工程应用价值。  相似文献   
72.
目的探讨超声引导下无负压甲状腺细针穿刺细胞学(US-FNAC)的学习曲线规律及其影响因素。 方法收集分析2017年6月至2018年月6月西安交通大学医学院附属陕西省肿瘤医院由同一医师完成的135例US-FNAC患者的操作耗时及临床病例资料,将患者按手术先后分9组(A~I组),每组15例定为一手术阶段后进行两两对比分析,比较各阶段的操作耗时、并发症及操作无效率。根据得出结果将135例患者分为前、中、后(X、Y、Z)3组,比较组间差异,进一步验证结果。 结果在A组至I组进行两两对比统计学分析得出,在A~D组间操作耗时均存在统计学差异(均P<0.05),在D组与E组间出现转折即两组比较差异无统计学意义(P=0.561),而E~I组间差异均无统计学意义(均P>0.05)。X、Y、Z 3组比较中,X组操作耗时明显长于Y组和Z组[分别为(6.23±1.38)min、(3.47±0.45)min、(3.21±0.45)min],X组与Y组和Z组差异均有统计学意义(t=18.07、23.15,均P<0.05),Y、Z两组对比无显著差异(t=1.92,P=0.067)。随着操作例数的增加,并发症及无效操作的发生率逐渐降低。 结论对于期望熟练掌握US-FNAC技术的超声医师,遵循对操作的全面认知和科学操作步骤,在指导下开展45例左右的US-FNAC后,可望快速安全越过学习曲线转折点。  相似文献   
73.
《Radiography》2020,26(4):e264-e269
IntroductionThe purpose of this experiment was to explore the direction of scattered secondary ionizing radiation to a patient. A left lateral radiographic examination of the elbow was deemed appropriate due to its close proximity to radiosensitive organs and record dose limiting opportunities upon wearing a lead-rubber apron.MethodsAn anthropomorphic phantom and lead-rubber apron (Pb 0.35 mm) was used with a 15 cc ionization chamber (model 10,100 AT TRIAD) to measure scattered radiation to radiosensitive organs. Dose readings were recorded before and after in order to quantify dose reduction. Pearson's correlation, linear regression, t-test and one way analysis of variance (ANOVA) statistics were used to affirm how likely dose limitation was attributed to chance (p < 0.05).ResultsThe lead-rubber apron offered dose reduction to most radiosensitive organs. Notably, ionizing radiation was significantly reduced to the left breast 0.0083 μGy (98%), right breast 0.0000 μGy (99.9%) and spleen 0.0262 μGy (99.9%). No empirical benefit was recorded for testes and ovaries. Interestingly, the thyroid recorded an increase in dose (0.1733 μGy; p = 0.01). This was later mitigated using a thyroid collar but identifies increased stochastic risks if lead-aprons are worn alone. Scattered radiation was also reduced to both eyes, which were not directly covered.ConclusionLead-rubber aprons are generally utilized to limit ionizing radiation, yet this article offers insight whereby increases to ionizing radiation to the thyroid are plausible when wearing a lead-rubber apron alone. Whilst these findings cannot be generalized to other radiographic examinations it provides insight into a potential increase risk of scatter to a radiosensitive organ.Implications for practiceThis paper has implications because it identifies that lead-rubber has an impact on scattered ionizing radiation to radiosensitive organs for a lateral elbow examination. Further, it identifies the potential for ionizing radiation to be increased to the thyroid upon wearing a lead-rubber apron alone.  相似文献   
74.
PurposeThyroid carcinoma (TC) is the most common endocrinal malignancy worldwide. Cyclin E2 (CCNE2), a member of the cyclin family, acts as a regulatory subunit of cyclin-dependent kinases (CDKs). It controls the transition of quiescent cells into the cell cycle, regulates the G1/S transition, promotes DNA replication, and activates CDK2. This study explored the role and potential molecular mechanisms of CCNE2 expression in TC tissues.Material/methodsImmunohistochemistry was used to evaluate the CCNE2 protein expression levels in TC. High-throughput data on CCNE2 in TC were obtained from RNA sequencing (RNA-seq), microarray, and literature data. The CCNE2 expression levels in TC were comprehensively assessed through an integrated analysis. Analyses of Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein–protein interaction (PPIs) data facilitated the investigation of the relative molecular mechanisms of CCNE2 in TC.ResultsThe immunohistochemical experiment showed a significant increase in the expression of CCNE2 in the TC tissues. For 505 TC and 59 non-cancerous samples from RNA-seq data, the area under the curve (AUC) was 0.8016 (95% confidence interval [CI] 0.742–0.8612; p<0.001). With another 14 microarrays, the pool standard mean difference [SMD] was 1.01 (95% CI [0.82–1.19]). The pooled SMD of CCNE2 was 1.12 (95% CI [0.60–1.64]), and the AUC was 0.87 (95% CI [0.84–0.90]) for 1157 TC samples and 366 non-cancerous thyroid samples from all possible sources. Nine hub genes were upregulated in TC.ConclusionsA high expression of CCNE2 may lead to carcinogenesis and the development of TC.  相似文献   
75.
BackgroundDICER1 syndrome is an inherited tumor predisposition syndrome. A germline mutation in DICER1 increases the risk for a spectrum of rare tumors. We describe a case of somatic DICER1 mutation in a pubertal girl, who is affected by different tumors of the DICER1 syndrome, including embryonal rhabdomyosarcoma (ERMS) of the cervix and thyroid adenoma.CaseA 16-year-old girl with history of papillary thyroid adenoma presented with abnormal vaginal bleeding and an exophytic cervical mass on examination. Histopathologic examination confirmed cervical ERMS. By using Sanger sequencing of the tumor, we identified 1 DICER1 mutation (c.3937delG).Summary and ConclusionThis report suggests that a patient with these 2 unrelated tumors (ERMS and papillary thyroid adenoma) should be promptly tested for DICER1 gene mutations.  相似文献   
76.
目的 比较常规剂量琥珀酰胆碱与小剂量罗库溴铵用于麻醉诱导对甲状腺手术患者术中喉返神经监测的影响。方法 选取2019年4月至2019年7月本院120例同一外科医师团队甲状腺手术喉返神经监测患者,随机分为A组:麻醉诱导肌松药物为琥珀胆碱1.5 mg/kg;B组:麻醉诱导肌松药物为罗库溴铵0.3 mg/kg。麻醉医师待肌松监测显示到最大抑制后,通过气管插管条件评分评估两组患者气管插管条件。记录各组插管时间、等待时间;迷走神经和喉返神经电信号基础值;以及术中血压波动、术后咽痛、声音嘶哑、低氧血症、苏醒延迟等并发症。外科医师通过神经肌电监测仪进行喉返神经刺激评估两组患者喉返神经监测情况。结果 A组患者气管插管条件优于B组,A组插管时间、肌松监测时间小于B组,两组手术监测时间差异无统计学意义。A组首次神经监测信号值大于B组,A组首次监测例数多于B组,两组患者术中无体动,血压下降差异无统计学意义。麻醉术后并发症,A组咽痛少于B组,A组有少量患者发生肌痛,差异无统计学意义。结论 1.5 mg/kg琥珀酰胆碱用于甲状腺手术患者的麻醉诱导,可以提供较好的插管条件,不影响外科医师术中行喉返神经监测,同时减少患者术后咽痛的发生。  相似文献   
77.
Thyroid cancer (TC) is known as the most prevalent form of endocrine malignancy. With regard to high heterogeneity of the nodules, problem of discriminating between benign and malignant ones in terms of pathological characteristics, as well as lack of appropriate molecular markers; significant efforts are being made to identify molecular markers that able to detect tumorous lesions. Survivin, the newest member of the family of proteins inhibiting cell apoptosis, has been recently considered as a novel molecule marker for cancer. Studies on TC have also demonstrated distinctive expression of survivin and its splice variants in cancer cells compared to normal ones. Therefore, detection of survivin expression and its new splice variants can be utilized to identify tumor nodules and distinguish them from non-cancerous ones, along with other routine laboratory methods.  相似文献   
78.
Papillary thyroid carcinoma (PTC) is the most common differentiated thyroid cancer in children; and the follicular variant is the second most common variant after the classic subtype. The histological appearance of follicular variant of papillary thyroid cancer (FVPTC), can be mimicked by benign follicular nodules. Pediatric pathologists encountering such lesions with FVPTC-like appearance may err on diagnosing the benign lesions as malignant. In adult patients, several immunohistochemical markers have emerged recently as a useful adjunct to distinguish differentiated thyroid carcinomas from benign follicular lesions. We undertook an inter-institutional retrospective study to establish the diagnostic utility of immunohistochemical staining for HBME-1, Galectin-3 and CD56 in differentiating FVPTC from its benign mimics, follicular adenoma and adenomatoid nodules, in children. Our specific aim of the project was to define the sensitivity and specificity of the three antibodies in FVPTC. Based on institutional diagnoses, a total of 66 cases were obtained: 32 FVPTC and 34 benign follicular nodules that comprised of 23 follicular adenoma and 11 adenomatoid nodules. Five investigators, who were blinded to the original diagnoses, independently reviewed the slides following pre-determined criteria and semi-quantitatively scoring the immunohistochemical staining. The immunohistochemical staining revealed that a combination of positive HBME-1 and negative CD56 result gave 100% specificity and positive predictive value in distinguishing FVPTC from benign follicular nodules. However, the antibody combination suffered from a lower sensitivity (50%). We used a cutoff of 25% positivity of tumor cells in determining positivity of tumor cells to an antibody. In conclusion, our study found a very high specificity and strong positive predictive value for the combination of HBME-1 and CD56 immunohistochemical stains in distinguishing FVPTC from benign follicular lesions.  相似文献   
79.
80.
目的探讨突变等位基因肿瘤异质性(MATH)在甲状腺乳头状癌(PTC)中的临床意义。 方法从癌症基因图谱公共数据集下载并预处理PTC肿瘤测序数据及临床资料数据,分析MATH与PTC临床病理特征的相关性,使用Kaplan-Meier法进行生存分析,验证MATH对PTC患者的预后价值。 结果PTC患者中MATH值为2.57~93.72,平均29.45±16.19;将≥29.45者纳入高MATH组,<29.45者纳入低MATH组。高MATH组与低MATH组的患者年龄、性别、临床分期、BRAF基因型差异无统计学意义(P>0.05)。MATH不是PTC患者总体生存期(OS)的显著预测因素(P=0.4595);在BRAF突变型PTC患者中,高MATH者的OS低于低MATH者(P=0.0252),而在BRAF野生型PTC患者中,高MATH者的OS高于低MATH者(P=0.0495)。 结论MATH可在BRAF突变型和野生型亚组中可预测PTC患者的预后及指导临床治疗。  相似文献   
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