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Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen.  相似文献   
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Modified-release opioids are often prescribed for the management of moderate to severe acute pain following total hip and knee arthroplasty, despite recommendations against their use due to increasing concerns regarding harm. The primary objective of this multicentre study was to examine the impact of modified-release opioid use on the incidence of opioid-related adverse events compared with immediate-release opioid use, among adult inpatients following total hip or knee arthroplasty. Data for total hip and knee arthroplasty inpatients receiving an opioid analgesic for postoperative analgesia during hospitalisation were collected from electronic medical records of three tertiary metropolitan hospitals in Australia. The primary outcome was the incidence of opioid-related adverse events during hospital admission. Patients who received modified with or without immediate-release opioids were matched to those receiving immediate-release opioids only (1:1) using nearest neighbour propensity score matching with patient and clinical characteristics as covariates. This included total opioid dose received. In the matched cohorts, patients given modified-release opioids (n = 347) experienced a higher incidence of opioid-related adverse events overall, compared with those given immediate-release opioids only (20.5%, 71/347 vs. 12.7%, 44/347; difference in proportions 7.8% [95%CI 2.3–13.3%]). Modified-release opioid use was associated with an increased risk of harm when used for acute pain during hospitalisation after total hip or knee arthroplasty.  相似文献   
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目的 比较腹腔镜和开腹手术治疗长径5~10 cm的中危胃间质瘤的安全性和有效性,并评估患者术后使用伊马替尼辅助治疗是否有明显益处。方法 回顾性分析2010年1月—2020年7月在南京大学医学院附属鼓楼医院接受手术治疗的72例长径在5~10 cm的中危胃间质瘤患者资料。其中腹腔镜手术组28例,开腹手术组44例。比较两组患者基本资料、病理特征、围手术期结果、住院总费用。对比术后使用和不使用伊马替尼辅助治疗的生存率。结果 开腹组和腹腔镜组临床病理特征差异无统计学意义(P>0.05)。腹腔镜组术后并发症发生率为32.1%(9/28),开腹组为52.3%(23/44),两组比较差异无统计学意义(P=0.094)。与开腹组相比,腹腔镜组总住院时间明显缩短[(12.5±3.2) d比(15.0±3.5) d,P=0.004];术后中位住院天数明显缩短(7.5 d 比 9.0 d,P=0.006);首次排气时间明显缩短(P=0.003)。中位随访时间58个月(13~129个月),期间未出现与肿瘤相关的死亡病例。开腹组有2例死亡,分别因乳腺癌和心脏病;腹腔镜组有1例死亡,死亡原因与胃间质瘤无关。72例患者中,40例术后接受伊马替尼辅助治疗,开腹组22例(50.0%),腹腔镜组18例(64.3%),两组接受伊马替尼辅助治疗的患者例数占比差异无统计学意义(χ2=1.414,P=0.234)。术后使用伊马替尼辅助治疗组总体生存率与未使用伊马替尼辅助治疗组相比差异有统计学意义 (P=0.015)。结论 与开腹手术相比,腹腔镜治疗长径在5~10 cm的中危胃间质瘤是一种安全有效的方法。实现R0切除的长径在5~10 cm的中危胃间质瘤患者术后使用伊马替尼辅助治疗未增加生存率,且未使用伊马替尼者未出现与肿瘤相关的死亡、复发及转移。  相似文献   
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Oral squamous cell carcinomas (OSCCs) develop in genetically altered epithelium in the mucosal lining, also coined as fields, which are mostly not visible but occasionally present as white oral leukoplakia (OL) lesions. We developed a noninvasive genetic assay using next-generation sequencing (NGS) on brushed cells to detect the presence of genetically altered fields, including those that are not macroscopically visible. The assay demonstrated high accuracy in OL patients when brush samples were compared with biopsies as gold standard. In a cohort of Fanconi anemia patients, detection of mutations in prospectively collected oral brushes predicted oral cancer also when visible abnormalities were absent. We further provide insight in the molecular landscape of OL with frequent changes of TP53, FAT1 and NOTCH1. NGS analysis of noninvasively collected samples offers a highly accurate method to detect genetically altered fields in the oral cavity, and predicts development of OSCC in high-risk individuals. Noninvasive genetic screening can be employed to screen high-risk populations for cancer and precancer, map the extension of OL lesions beyond what is visible, map the oral cavity for precancerous changes even when visible abnormalities are absent, test accuracy of promising imaging modalities, monitor interventions and determine genetic progression as well as the natural history of the disease in the human patient.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - Ferromagnetic foreign bodies (FFB) present during magnetic resonance imaging (MRI) explorations can lead to tissue injury due to...  相似文献   
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地鳖中的纤溶活性蛋白是从地鳖中提取的具有抗栓及抗肿瘤作用的有效成分,其口服易被上消化道酶分解从而限制了应用。采用恒流泵滴制法开发地鳖纤溶活性蛋白时间/pH依赖口服结肠靶向微囊(EnpolypHaga fibrinolytic protein oral colon targeting microcapsules, CTM-EFP)。采用单因素实验和正交实验相结合的方法寻找到包封率为60.17 % ± 2.72 %、载药量为15.50 % ± 0.44 % 的最佳配方。扫描电子显微镜(SEM)显示微囊呈球形、表面光滑,在人工肠液中24 h的累积释放度为99.53 % ± 0.69 %,在人工胃液中24 h累积释放度为7.43 ± 1.04 %,通过时间/pH依赖达到结肠靶向作用。CTM-EFP在人工肠液中的体外释放曲线符合Korsmeyer方程,提示地鳖纤溶活性蛋白(EnpolypHaga fibrinolytic protein, EFP)是通过扩散和侵蚀机制结合释放的。CTM-EFP为EFP的口服给药提供了一种新的剂型,为EFP应用于临床提供参考。  相似文献   
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Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study...  相似文献   
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