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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.
Ventilation imaging of the lung: Comparison of hyperpolarized helium-3 MR imaging with Xe-133 scintigraphy 总被引:1,自引:0,他引:1
Talissa A. Altes MD Patrice K. Rehm MD Frank Harrell PhD Michael Salerno PhD Thomas M. Daniel MD Eduard E. de Lange MD 《Academic radiology》2004,11(7):729-734
RATIONALE AND OBJECTIVES: To compare hyperpolarized helium-3 (HHe) magnetic resonance imaging (MRI) of the lung with standard Xe-133 lung ventilation scintigraphy. MATERIALS AND METHODS: We performed a retrospective review of 15 subjects who underwent HHe MRI and Xe-133 lung ventilation imaging. Coronal MRI sections were acquired after a single inhalation of HHe gas, and standard posterior planar lung ventilation scintigraphy was performed during continuous breathing of Xe-133 gas. The first breath scintigram of each patient was compared with a composite MR image composed of the sum of the individual MR images and with the individual helium-3 MR images. Ventilation defects on the two imaging modalities were compared for size, conspicuity, and concordance in presence and location. Assessment was done separately for each of four lung quadrants. RESULTS: Comparing the composite HHe MR images with Xe-133 scintigraphy, ventilation defect size, conspicuity and concordance were the same in 67% (40/60), 63% (38/60), and 62% (37/60) quadrants, respectively. Comparing the individual HHe MR image sections with the Xe-133 ventilation scan, there was concordance between the ventilation defects in 27% (16/60) of quadrants. More defects were identified on the individual HHe MR images in 62% (37/60) of quadrants. CONCLUSION: There was good agreement between composite HHe MR image and first breath Xe-133 scintigraphic images, supporting the widely held assumption that HHe MRI likely depicts first breath lung ventilation. 相似文献
3.
目前国内外研究发现自体和异体骨髓干细胞移植可增加脑梗死周围区域的血管数量[1]。但在脑梗死后,机体自身内皮干细胞是否参与梗死周围区域的新血管形成尚无报道。AC133(又称CD133)是新发现的造血干祖细胞糖蛋白抗原,在已分化的内皮细胞上不表达,在内皮前体细胞表达[2],AC133蛋白和基因是否在大脑缺血脑组织表达以及局部缺血后AC133是否参与血管内皮功能等问题尚无文献提及。本研究将初探大鼠局灶脑缺血后脑组织中AC133抗原和AC133mRNA的表达。1资料1.1动物分组及模型制备:雄性SD大鼠42只,体重250~350g,随机分成3组:正常对照组、假… 相似文献
4.
E. B. Andersen F. Boesen O. Henriksen 《Clinical physiology and functional imaging》1991,11(5):451-458
Summary. The effect of age and sex on relative changes in blood flow and vascular resistance in skeletal muscle and subcutaneous tissue during postural changes and during local increase in transmural pressure was studied in 33 healthy subjects. The intra-individual variation was studied in five subjects. Blood flow was measured by the local 133Xenon wash-out method. No relation to age or sex was seen in the centrally elicited sympathetic vasoconstrictor responses in subcutaneous tissue and skeletal muscle and in the locally elicited vasoconstriction in subcutaneous tissue. A small, but statistically significant, correlation to sex and age was found in the local sympathetic vasoconstrictor response in skeletal muscle. The age correlation was caused only by an attenuated response in the young subjects below 40 years of age and may be fortuitous. The intra-individual variation was acceptably small. Based on the present results, a reduction in blood flow in skeletal muscle and subcutaneous tissue during centrally or locally elicited sympathetic vasoconstriction of 10% or less should be considered abnormal. The local 133Xenon wash-out method is of value in examining patients suspected of dysfunction in the sympathetic part of the autonomic nervous system. 相似文献
5.
青少年近视患者配戴渐进多焦眼镜的视光学检查现状初步分析 总被引:4,自引:0,他引:4
目的:调查青少年近视患者配戴渐进多焦眼镜的现状,分析其对眼部参数的影响。方法:随机抽查配戴渐进光眼镜的近视患者214名,对其进行视光学检查,包括屈光度、斜视度、AC/A率、辐接近点和融合范围等项目,并调查其心理感受。其检查结果与256名年龄相匹配的戴用单焦眼镜的近视患者相对照,分析其变量的变化。结果:配戴渐变多焦眼镜的近视患者中140例无不适感觉,满意程度明显高于对照组;屈光度平均为-3.5D,约半数患者(48.6%)存在不同程度的外隐斜,其中8位是间歇性外斜患者,没有融合能力,辐辏近点大于20 cm;平均AC/A率为(2.95±1.49),平均融合力为+16.41°~-7.06°,平均辐转近点为(72.63±24.42)mm。实验组除AC/A率低于对照组(t=3.52,P<0.05),且与屈光度无明显相关(r=-0.0318,P>0.05)外,其余检查与对照组之间没有显著性差别。结论:渐进多焦眼镜可以引起AC/A率降低,并有可能通过掩饰间歇性外斜患者 的症状而耽误其治疗。因此,渐进多焦眼镜虽然普遍受青少年近视患者欢迎,但验配中仍存在适应证选择问题,青少年在验配时最好在医生的指导下进行。 相似文献
6.
目的评估AO肩锁钢板钩治疗重型肩锁关节脱位的手术疗效.方法回顾性分析两年来27例手术病人的手术治疗和疗效.结果手术方法符合生理结构,手术时间平均30分钟,内固定牢靠.根据Murley和Constant[1]评分,优良率94%.结论 AO肩锁钢板钩治疗重型肩锁关节脱位,手术方法简单,疗效可靠,允许病人术后早期功能锻炼. 相似文献
7.
目的 通过对人胎盘CD133+细胞群中高增殖潜能集落形成细胞(HPP-CFC)检测与生物学特性的分析,证明人胎盘存在早期造血干/祖细胞(HSPC)。 方法 采用机械法制备人胎盘组织(PT)单细胞悬液,用Histopaque-1007分离出单个核细胞(MNC),经磁式分选(MACS)富集CD133+细胞,培养28 d后观察HPP-CFC集落形成能力,用流式细胞仪(FCM)对分选的细胞组份和HPP-CFC进行表型分析,实验全程用脐带血(UCB)作平行比较分析。 结果 培养28 d后,PT-CD133+与UCB-CD133+细胞组份分别扩增了266和362倍,前者低于后者(P<0.01);PT-CD133+与UCB-CD133+细胞中HPP-CFC分别为(32.4±11.2)/5×103、(17. 7±5.7)/5×103,前者形成的HPP-CFC数量明显高于后者(P<0.01);PT-CD133+、UCB-CD133+细胞培养至28 d时,除UCB-CD133+组的CD133+CD34-亚群比例无明显改变外,CD133+CD34+、CD133-CD34+和CD133+CD34-(PT-CD133+组)亚型均比培养前减少。 结论 人胎盘组织CD133+细胞中存在HPP-CFC,说明胎盘CD133+细胞群中存在早期HSPC。 相似文献
8.
9.
Losi L Scarselli A Benatti P Ponz de Leon M Roncucci L Pedroni M Borghi F Lamberti I Rossi G Marino M Ponti G Zangardi G Menigatti M Di Gregorio C 《Pathology, research and practice》2004,200(5):371-377
The main purpose of this study was to examine the expression of mucins and mismatch repair proteins in colorectal carcinomas. The immunohistochemical distribution of apomucins MUC2, MUC5AC, and the expression of MLH1 and MSH2 proteins were examined in 76 mucinous and 60 non-mucinous colorectal carcinomas. MUC2 was noted in all mucinous carcinomas, whereas MUC5AC was present in 41 cases only (54%). In non-mucinous carcinomas, MUC2 was expressed in 61.7% of the tumors; by contrast, MUC5AC was present in 20% of the cases. The expression level of apomucins was significantly different in mucinous and non-mucinous lesions (p<0.001). Twenty-seven (35.5%) of the mucinous carcinomas showed no MLH1 expression, whereas 11 (18.3%) of the non-mucinous tumors did. This difference was statistically significant (p<0.005). Altered expression of MSH2 protein was never observed. The lack of MLH1 expression was considerably more frequent in carcinomas with secretion of MUC5AC (p<0.005). Our study has demonstrated this close relationship by immunohistochemical methods. In summary, our data show: (1) differences in the expression of mucins between mucinous and non-mucinous tumors; (2) a high frequency of altered MLH1 protein expression (35.5%) in mucinous carcinomas; (3) a significant relationship between the presence of MUC5AC and the altered expression of MLH1 protein in colorectal carcinomas. 相似文献
10.
Bin Yu Youming Ding Xiaofeng Liao Changhua Wang Bin Wang Xiaoyan Chen 《Pathology, research and practice》2019,215(5):939-945