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《European journal of surgical oncology》2022,48(4):783-788
BackgroundInvestigation of lymph node micrometastasis (mN) of gastric cancer has been focused on either T1 disease or T1-4N0 disease. Yet, it is unclear whether standard management algorithm toward poorly differentiated gastric cancer (PDGC) is more vulnerable to existence of mN, given its inherently biological aggressiveness, as compared with other histological types.Patients and methodsA surgical series (n = 3456) of gastric cancer categorized by histological differentiation was enrolled to analyze survival stratification. Of them, a cohort of T1-T4 N0 PDGC (n = 100) were subjected to cytokeratin immunohistochemistry, a surrogate of mN.ResultsCancer-specific survival by AJCC8 staging system could be nicely differentiated in both well-/moderately differentiated and signet ring cell types, while those between stage IA versus IB (p = 0.105), and stage IB versus IIA (p = 0.141) in PDGC could not. Thirteen (13%) out of 100 node-negative PDGC cases exhibited mN, with 5, 2, 5 and 1 cases occurring in T1, T2, T3, and T4 stage, respectively, without identifiable contributing factors. Prognostic performance of AJCC8 working upon PDGC became more discriminative by incorporating mN, as hazard ratio of stage IIIC referenced to stage IA increased from 43 to 78.ConclusionDefective discriminative survival of PDGC by standard staging algorithm prompted us to survey mN occurring in T1-T4N0 PDGC. The prognostic performance of AJCC8 working upon PDGC was enhanced by incorporating mN. As so, we recommend documentation of mN exclusively on node-negative PDGC that helps unveil stage migration phenomenon and switch to appropriate adjuvant therapy in need. 相似文献
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Objectives:To reassess the long-term camouflage effects of resin infiltration (Icon, DMG, Hamburg, Germany) of white spot lesions (WSL) and sound adjacent enamel (SAE) achieved in a previous trial. The null hypothesis was tested that there were no significantly different CIE-L*a*b*-ΔE-values between WSL and SAE areas of assessment after at least 24 months (T24) compared to those at baseline (T0).Materials and Methods:Of twenty subjects who received previous resin infiltration treatment of nteeth = 111 nonrestored, noncavitated postorthodontic WSL after multibracket treatment during a randomized controlled trial and were contacted 20 months after baseline, eight subjects (trial teeth nteeth = 40; m/f ratio 1/7; age range (mean; SD) 12–17 [15.25; 2.12] years); response rate: 40%) were available for follow-up after at least 24 months (T24). CIE-L*a*b* differences between summarized color and lightness values (ΔEWSL/SAE) of WSL and SAE were assessed using a spectrophotometer and compared to baseline data assessed prior to infiltration (T0), and those after 6 (T6), and 12 (T12) months using paired t tests at a significance level of α = 5%.Results:T24 assessments were performed after a mean 33.86 (SD: 8.64; Min: 24; Max: 45) months following T0. Mean (SD) ΔEWSL/SAE units of available teeth were 8.76 (5.33) at baseline; 5.5 (2.75) at T6; 5.2 (2.41) at T12; and 5.57 (2.6) at T24. Comparisons of T6, T12, and T24 with T0 yielded highly significant differences, whereas T6–T24 and T12–T24 differences were found to be not significant.Conclusions:Assimilation of infiltrated WSL to the color of adjacent enamel by resin infiltration is considered to be suitable for the long-term improvement in the esthetic appearance of postorthodontic WSL. 相似文献
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目的:观察理气中药经验组方对糖尿病大鼠胃排空延迟的干预作用。方法:雌雄各半成年SD大鼠110只,随机分为正常组(A组)、糖尿病中药组(B组)、糖尿病胃复安组(C组)、糖尿病组(D组)。A组、D组1次/d按10 mL/只予0.9%生理盐水灌胃,B组1次/d按8 mL/只予中药煎剂灌胃,C组1次/d按0.5 mg/只予胃复安片灌胃。喂养12周后,行13C胃排空实验及甲基橙水溶液胃排空实验,观察各组大鼠胃排空情况。结果:糖尿病大鼠胃排空较正常大鼠明显延迟(P0.01),糖尿病大鼠胃排空延迟模型制作成功。糖尿病中药组和糖尿病胃复安组大鼠胃排空较糖尿病组快(P0.01);糖尿病中药组大鼠胃排空较糖尿病胃复安组大鼠快(P0.05)。结论:常规喂养12周后糖尿病大鼠出现胃排空延迟。理气中药陈皮、枳实、木香、香附组方煎剂和胃复安均能促进糖尿病大鼠胃排空,理气中药组方煎剂的效果优于胃复安。 相似文献
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Thomas Asendorf Robin Henderson Heinz Schmidli Tim Friede 《Statistics in medicine》2019,38(9):1503-1528
In some diseases, such as multiple sclerosis, lesion counts obtained from magnetic resonance imaging (MRI) are used as markers of disease progression. This leads to longitudinal, and typically overdispersed, count data outcomes in clinical trials. Models for such data invariably include a number of nuisance parameters, which can be difficult to specify at the planning stage, leading to considerable uncertainty in sample size specification. Consequently, blinded sample size re-estimation procedures are used, allowing for an adjustment of the sample size within an ongoing trial by estimating relevant nuisance parameters at an interim point, without compromising trial integrity. To date, the methods available for re-estimation have required an assumption that the mean count is time-constant within patients. We propose a new modeling approach that maintains the advantages of established procedures but allows for general underlying and treatment-specific time trends in the mean response. A simulation study is conducted to assess the effectiveness of blinded sample size re-estimation methods over fixed designs. Sample sizes attained through blinded sample size re-estimation procedures are shown to maintain the desired study power without inflating the Type I error rate and the procedure is demonstrated on MRI data from a recent study in multiple sclerosis. 相似文献
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《Surgery for obesity and related diseases》2020,16(8):1060-1066
BackgroundSingle-anastomosis duodeno-ileal bypass (SADI) and the one-anastomosis gastric bypass (OAGB) are 2 revisional procedures to address the problem of weight recidivism after laparoscopic sleeve gastrectomy (LSG).ObjectivesTo evaluate the efficacy and safety of SADI and OAGB as revisional bariatric surgery (RBS) in initially super-obese patients (body mass index [BMI] >50 kg/m2).SettingAcademic hospital, bariatric center of excellence, Germany.MethodsObservational study of outcomes in 84 initially super-obese patients who had undergone RBS after LSG (SADI n = 42, OAGB n = 42) between July 2013 and April 2018. Follow-up examinations were performed at 1, 6, 12, 24, and 36 months after RBS. The variables analyzed included time between LSG and RBS, BMI, excess weight loss, total weight loss, operation time, and complications.ResultsThe time interval between LSG and RBS was 45.5 ± 22.8 and 43.5 ± 24.2 months for SADI and OAGB, respectively. At the time of RBS, the mean BMI was 42.8 ± 7.9 kg/m2 for SADI and 43.4 ± 9.2 kg/m2 for OAGB. The follow-up examinations rates (%) after SADI were 97.6, 92.8, 90.5, 78.6, 57.1, and 100, 97.6, 95.2, 85.7, and 59.5 after OAGB. The BMI at the follow-up examinations were 39.1 ± 7.2, 34.2 ± 6.9, 31.2 ± 5.8, 30.2 ± 5.3, 29.3 ± 5.1 for SADI, and 39.5 ± 8.1, 36.6 ± 7.4, 34.7 ± 7.9, 32.9 ± 6.3, and 31.6 ± 5.9 for OAGB. The mean operating times for SADI and OAGB were 138 ± 40 and 123 ± 39 minutes, respectively. Three patients in the SADI group and 1 patient in the OAGB group developed a major complication within the first 30 postoperative days.ConclusionSADI and OAGB were effective second-step procedures for further weight reduction after LSG in initially super-obese patients after short to medium follow-up. There was a trend toward higher weight loss for SADI though this did not reach statistical significance. Substantial differences concerning surgery time and complications between the 2 procedures were not observed. 相似文献
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胃癌在全国范围内是发病率最高的恶性肿瘤之一,在癌症相关死亡原因中排名第三。目前外科手术仍然是胃癌获得根治性治疗的主要手段,但是其中有30%~40%的进展期胃癌患者在初诊时就失去了根治手术的机会,因此不可切除胃癌转化为可切除胃癌是患者获得"治愈"的最佳选择。随着近些年来新型药物的出现、治疗手段的多样化及多学科诊治模式的发展,"转化治疗"的理念应运而生,从而延长患者生存时间并提高其生活质量。本文就不可切除胃癌的治疗现状与进展、"转化治疗"的应用等进行综述。 相似文献