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排序方式: 共有242条查询结果,搜索用时 171 毫秒
1.
Whitney S. Brandt Wanpu Yan Jian Zhou Kay See Tan Joseph Montecalvo Bernard J. Park Prasad S. Adusumilli James Huang Matthew J. Bott Valerie W. Rusch Daniela Molena William D. Travis Mark G. Kris Jamie E. Chaft David R. Jones 《The Journal of thoracic and cardiovascular surgery》2019,157(2):743-753.e3
Objective
Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.Methods
Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.Results
In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.Conclusions
Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection. 相似文献2.
MRP1/CD9蛋白在人肝细胞癌中的表达及其意义 总被引:1,自引:0,他引:1
目的 探讨MRP1 /CD9蛋白在人肝细胞癌 (HCC)中的表达及其与癌侵袭转移的关系。方法 构建肝癌组织芯片。样本包括肝细胞癌及癌旁肝组织 1 5 2例,癌栓 2 2例,肝内转移癌 4例,肝外转移癌 1 7例。正常对照肝组织 5例。应用免疫组织化学 (免疫组化 )方法检测肝癌组织芯片中样本MRP1 /CD9蛋白的表达。结果 2 7% ( 4 1 /1 5 2 )肝细胞癌原发灶表达MRP1 /CD9蛋白。伴癌栓形成HCC中MRP1 /CD9蛋白表达率低于无癌栓形成者 (分别为 2 1. 8 2%和 4 0. 4 8% ; P < 0. 0 5 )。巨块型肝癌中MRP1 /CD9 蛋白表达率亦低于直径在 1 0cm以下者 (分别为 5%和 3 4. 8 2% ; P <0. 01 )。MRP1 /CD9蛋白表达尚与HCC病理分级及血清AFP水平有关:病理分级 2级的阳性表达率高于 3 ~ 4级 (分别为 3 9. 0 2%和 2 2. 5 2% ; P = 0. 0 4 3 ),血清AFP≤ 2 0μg/L者阳性表达率高于 >2 0μg/L者 (分别为 4 1. 9 4%和 2 2. 5 0% ; P = 0. 0 2 9 )。结论 肝细胞癌MRP1 /CD9蛋白表达水平低下可能与癌组织侵袭转移有关。 相似文献
3.
PURPOSE: To test, whether axial, coronal and sagittal MIP and MPR reconstructions of diagnostic quality can be obtained from 1-mm collimation MSCT data of the chest for the evaluation of thoracic anatomy and pathology. MATERIALS AND METHODS: 1-mm collimation MSCT scans were obtained with a pitch of 6 in an acrylic phantom and in 20 patients. Axial images were reconstructed with 0.6-mm increment. Multiplanar reformations (MPRs) and sliding thin-slab maximum intensity projections (STS-MIPs) were reconstructed in axial, coronal and sagittal planes. Images were printed in lung windows and evaluated by three readers by using a standardized evaluation scheme. RESULTS: Overall, both methods allowed good visualization of anatomic structures. MIP was superior for visualization of the pulmonary arteries (p < 0.05) while central and peripheral bronchi and the lung parenchyma were better depicted on multiplanar reconstructions. A confident diagnosis of thoracic pathology was feasible using both modalities, however MIPs appeared less usefull for evaluation of gross parenchymal abnormalities, such as pneumonic infiltrates or fibrotic changes. No significant difference in the degree of motion artifacts were detected between both modalities. CONCLUSION: MSCT data sets are ideally suited for generating MPR and MIP reconstructions. While MIPs are superior for the evaluation of thoracic vessels, MPR is advantageous for visualizing central and peripheral bronchi and the pulmonary parenchyma. 相似文献
4.
5.
John D. Biglands Montasir Ibraheem Derek R. Magee Aleksandra Radjenovic Sven Plein John P. Greenwood 《JACC: Cardiovascular Imaging》2018,11(5):711-718
Objectives
This study sought to compare the diagnostic accuracy of visual and quantitative analyses of myocardial perfusion cardiovascular magnetic resonance against a reference standard of quantitative coronary angiography.Background
Visual analysis of perfusion cardiovascular magnetic resonance studies for assessing myocardial perfusion has been shown to have high diagnostic accuracy for coronary artery disease. However, only a few small studies have assessed the diagnostic accuracy of quantitative myocardial perfusion.Methods
This retrospective study included 128 patients randomly selected from the CE-MARC (Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease) study population such that the distribution of risk factors and disease status was proportionate to the full population. Visual analysis results of cardiovascular magnetic resonance perfusion images, by consensus of 2 expert readers, were taken from the original study reports. Quantitative myocardial blood flow estimates were obtained using Fermi-constrained deconvolution. The reference standard for myocardial ischemia was a quantitative coronary x-ray angiogram stenosis severity of ≥70% diameter in any coronary artery of >2 mm diameter, or ≥50% in the left main stem. Diagnostic performance was calculated using receiver-operating characteristic curve analysis.Results
The area under the curve for visual analysis was 0.88 (95% confidence interval: 0.81 to 0.95) with a sensitivity of 81.0% (95% confidence interval: 69.1% to 92.8%) and specificity of 86.0% (95% confidence interval: 78.7% to 93.4%). For quantitative stress myocardial blood flow the area under the curve was 0.89 (95% confidence interval: 0.83 to 0.96) with a sensitivity of 87.5% (95% confidence interval: 77.3% to 97.7%) and specificity of 84.5% (95% confidence interval: 76.8% to 92.3%). There was no statistically significant difference between the diagnostic performance of quantitative and visual analyses (p = 0.72). Incorporating rest myocardial blood flow values to generate a myocardial perfusion reserve did not significantly increase the quantitative analysis area under the curve (p = 0.79).Conclusions
Quantitative perfusion has a high diagnostic accuracy for detecting coronary artery disease but is not superior to visual analysis. The incorporation of rest perfusion imaging does not improve diagnostic accuracy in quantitative perfusion analysis. 相似文献6.
《Radiography》2016,22(4):e228-e232
IntroductionZygomatic fractures can be diagnosed with either computed tomography (CT) or direct digital radiography (DR). The aim of the present study was to assess the effect of CT dose reduction on the preference for facial CT versus DR for accurate diagnosis of isolated zygomatic fractures.Materials and methodsEight zygomatic fractures were inflicted on four human cadavers with a free fall impactor technique. The cadavers were scanned using eight CT protocols, which were identical except for a systematic decrease in radiation dose per protocol, and one DR protocol. Single axial CT images were displayed alongside a DR image of the same fracture creating a total of 64 dual images for comparison. A total of 54 observers, including radiologists, radiographers and oral and maxillofacial surgeons, made a forced choice for either CT or DR.ResultsForty out of 54 observers (74%) preferred CT over DR (all with P < 0.05). Preference for CT was maintained even when radiation dose reduced from 147.4 μSv to 46.4 μSv (DR dose was 6.9 μSv). Only a single out of all raters preferred DR (P = 0.0003). The remaining 13 observers had no significant preference.ConclusionThis study demonstrates that preference for axial CT over DR is not affected by substantial (∼70%) CT dose reduction for the assessment of zygomatico-orbital fractures. 相似文献
7.
目的探讨64排螺旋CT及其MPR技术对肺尘埃沉着病合并肺结核的诊断价值。方法对50例肺尘埃沉着病患者进行胸部64排螺旋CT检查,得到胸部轴位(层厚1 mm)及MPR图像,分析肺尘埃沉着病合并肺结核CT表现,对早期发现肺尘埃沉着病合并结核有重要价值。结果肺尘埃沉着病合并血行播散型肺结核1例,继发性肺结核48例,其中渗出浸润为主32例,占66%;干酪为主型6例,占12.5%;空洞为主型10例,占20.8%;肺尘埃沉着病合并结核性胸膜炎1例,占0.2%。结论 64排螺旋CT及MPR技术对肺尘埃沉着病合并结核的诊断优势明显。MPR技术对胸部整体情况能多方位,直观,清晰和形象地显示,特别是晚期肺尘埃沉着病合并结核早期诊断提供较为可靠依据。 相似文献
8.
9.
Rapid decrease in tuberculin skin test reactivity at preschool age after newborn vaccination 总被引:2,自引:0,他引:2
L Kröger ML Katila M Korppi E Brander M Pietikäinen 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(9):678-681
A study of tuberculin sensitivity was performed in 353 children aged 4-6 years, all vaccinated at birth with British BCG vaccine. Significant waning of tuberculin reactions with increasing age was found (p < 0.05). In the age group < 4.5 years, the mean tuberculin reaction was 6.6 mm, in the age group 4.5-5.5 years 5.2 mm and in the age group of > 5.5 years 3.5 mm. The number of children with positive reactions (> or = 5 mm) was 165 (40%) and those with strong reactions (> or = 10 mm) 49 (14%). None of the latter children had active tuberculosis during a follow-up period of 12 months. Eighty-three (24%) of the children had no reaction. The children who had been revaccinated with the MPR vaccine against measles, rubella and parotitis (n = 31) had significantly larger tuberculin reactions than the non-revaccinated children. Atopic dermatitis or infections during the preceding six months did not have any significant influence on reaction sizes. Our results demonstrate that the variation in size of tuberculin reactions after BCG vaccination at birth is large. We conclude that tuberculin sensitivity wanes rapidly by the age of 4.0-6.3 years. 相似文献
10.
目的:探讨16排螺旋CT在头颈部血管一次性成像的技术及其临床价值。方法:收集30例2006年1月至5月怀疑头颈部血管有异常改变的患者,GE公司Lightspeed16排螺旋CT机行头颈部血管造影检查,应用MPR、SSD、MIP、CPR等技术进行重建。结果:一次性成像的质量和延时时间、层厚、螺距、后处理密切相关,可清楚显示头颈部动脉。结论:16排螺旋CT对头颈部血管造影检查是一种有效的无创检查方法,只要方法得当可较好的显示头颈部动脉并对头颈部血管病变的诊断有较好的临床价值。 相似文献