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91.
《Diagnostic and interventional imaging》2020,101(9):565-575
PurposeTo report the computed tomography (CT) features of pancreatic acinar cell carcinoma (ACC) and identify CT features that may help discriminate between pancreatic ACC and pancreatic ductal adenocarcinoma (PDA).Materials and methodsThe CT examinations of 20 patients (13 men, 7 women; mean age, 66.5 ± 10.7 [SD] years; range: 51–88 years) with 20 histopathologically proven pancreatic ACC were reviewed. CT images were analyzed qualitatively and quantitatively and compared to those obtained in 20 patients with PDA. Comparisons were performed using univariate analysis with a conditional logistic regression model.ResultsPancreatic ACC presented as an enhancing (20/20; 100%), oval (15/20; 75%), well-delineated (14/20; 70%) and purely solid (13/20; 65%) pancreatic mass with a mean diameter of 52.6 ± 28.0 (SD) mm (range: 24–120 mm) in association with visible lymph nodes (14/20; 70%). At univariate analysis, well-defined margins (Odds ratio [OR], 7.00; P = 0.005), nondilated bile ducts (OR, 9.00; P = 0.007), visible lymph nodes (OR, 4.33; P = 0.028) and adjacent organ involvement (OR, 5.67; P = 0.02) were the most discriminating CT features to differentiate pancreatic ACC from PDA. When present, lymph nodes were larger in patients with pancreatic ACC (14 ± 4.8 [SD]; range: 7–25 mm) than in those with PDA (8.8 ± 4.1 [SD]; range: 5–15 mm) (P = 0.039).ConclusionOn CT, pancreatic ACC presents as an enhancing, predominantly oval and purely solid pancreatic mass that most frequently present with no bile duct dilatation, no visible lymph nodes, no adjacent organ involvement and larger visible lymph nodes compared to PDA. 相似文献
92.
目的:探讨术前预后营养指数(PNI)、中性粒细胞/淋巴细胞比值(NLR)、血小板/淋巴细胞比值(PLR)、淋巴细胞/单核细胞比值(LMR)对患者因壶腹周围癌而行胰头十二指肠切除术后发生胰瘘的预测价值。方法:回顾性分析中国医科大学附属盛京医院收治的140例手术切除治疗的壶腹周围癌病例资料。采用受试者工作特征曲线(ROC)、多因素回归分析确定术前NLR、PLR、LMR、PNI对术后胰瘘的预测价值。结果:共筛选出30例术后临床胰瘘(B级瘘和C级瘘)患者,累积发生率为21.43%(30/140),其中C级瘘为8例,发生率为5.71%(8/140)。术前NLR、PLR、LMR、PNI预测术后胰瘘的最佳截断值分别为3.49、150.79、2.48、44.8。进一步行多因素回归分析得出术前合并糖尿病、NLR≥3.49、LMR<2.48及PNI<44.8是胰头十二指肠切除术后并发胰瘘的独立危险因素(P<0.05)。术前高NLR(≥3.49)、低PNI(<44.8)的患者术后发生严重的C级胰瘘的可能更大(P<0.05)。应用胰瘘风险评分系统(FRS)对患者进行分层,其中21例处于高风险层次,进一步分析得到处于高风险层次的患者当同时合并术前高NLR、低PNI与低LMR中多项不良因素时,术后胰瘘的发生率可显著升高(78.57%,P=0.016)。结论:术前高NLR、低LMR、低PNI对胰头十二指肠切除术后患者并发胰瘘具有一定的预测价值;术前NLR、PNI水平与胰瘘的严重程度等级(B级瘘、C级瘘)具有相关性;处于FRS评分高风险层次的PD患者,当同时合并术前高NLR、低PNI与低LMR中多项时,术后发生胰瘘的风险增高。 相似文献
93.
目的探讨新辅助治疗前后中性粒细胞与淋巴细胞比值(NLR)及血小板与淋巴细胞比值(PLR)变化在直肠癌新辅助治疗中的意义。方法回顾性分析2013年11月至2015年1月山西省肿瘤医院收治的86例接受新辅助治疗的直肠癌患者资料,分析新辅助治疗前后NLR、PLR变化与患者临床病理特征及疗效的关系。结果86例患者治疗后NLR、PLR升高均为43例。直肠癌患者新辅助治疗前后的NLR及PLR变化与患者年龄、性别、TNM分期、淋巴结转移及癌结节数量、肿瘤长径均无关(均P>0.05),肿瘤与肛门距离<6 cm者治疗后NLR、PLR升高者比例均高于≥6 cm者[60.00%(30/50)比36.11%(13/36),χ^2=4.778,P=0.029;64.00%(32/50)比30.56%(11/36),χ^2=9.364,P=0.002];体质量指数≥28 kg/m2者治疗后NLR、PLR升高者比例均高于<28 kg/m2者[81.82%(9/11)比45.33%(34/75),χ^2=5.108,P=0.024;90.91%(10/11)比44.00%(33/75),χ^2=8.444,P=0.004]。治疗后NLR降低组患者的缓解率高于NLR升高组[72.09%(31/43)比51.16%(31/43),χ^2=3.983,P=0.046],而治疗前后PLR变化与患者新辅助治疗效果无关(P>0.05)。结论直肠癌患者新辅助治疗前后NLR变化与其疗效相关。 相似文献
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《Health & place》2020
This study estimated the associations between neighbourhood characteristics and self-reported body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) risk categories among Canadian men and women. Using data from the Alberta's Tomorrow Project (n = 14,550), we estimated 3- and 4-way intersections, business destinations, population count, and normalized difference vegetation index (NDVI) within a 400 m radius of participant's home. Intersections, business destinations, and population count (z-scores) were summed to create a walkability score. Four-way intersections and walkability were negatively associated with overweight and obesity. Walkability was negatively associated with obesity. NDVI was negatively associated with high-risk WHR and population count and walkability positively associated with high-risk WHR. Among men, population count and walkability were negatively associated with obesity, and business destinations and walkability were negatively associated with overweight and obesity. Among women, NDVI was negatively associated with overweight (including obesity), obesity, and high-risk WC. Interventions promoting healthy weight could incorporate strategies that take into consideration local built environment characteristics. 相似文献
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Dean Follmann Michael P Fay Toshimitsu Hamasaki Scott Evans 《Statistics in medicine》2020,39(5):602-616
Composite endpoints are frequently used in clinical trials, but simple approaches, such as the time to first event, do not reflect any ordering among the endpoints. However, some endpoints, such as mortality, are worse than others. A variety of procedures have been proposed to reflect the severity of the individual endpoints such as pairwise ranking approaches, the win ratio, and the desirability of outcome ranking. When patients have different lengths of follow-up, however, ranking can be difficult and proposed methods do not naturally lead to regression approaches and require specialized software. This paper defines an ordering score O to operationalize the patient ranking implied by hierarchical endpoints. We show how differential right censoring of follow-up corresponds to multiple interval censoring of the ordering score allowing standard software for survival models to be used to calculate the nonparametric maximum likelihood estimators (NPMLEs) of different measures. Additionally, if one assumes that the ordering score is transformable to an exponential random variable, a semiparametric regression is obtained, which is equivalent to the proportional hazards model subject to multiple interval censoring. Standard software can be used for estimation. We show that the NPMLE can be poorly behaved compared to the simple estimators in staggered entry trials. We also show that the semiparametric estimator can be more efficient than simple estimators and explore how standard Cox regression maneuvers can be used to assess model fit, allow for flexible generalizations, and assess interactions of covariates with treatment. We analyze a trial of short versus long-term antiplatelet therapy using our methods. 相似文献