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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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Introduction

Left ventricular (LV) dysfunction is estimated to occur in 10%–25% of the general intensive care unit (ICU) population and is frequently seen as regional wall motion abnormalities (RWMAs). Although RWMA is mostly attributed to myocardial ischemia or infarction, some studies have suggested that nonischemic RWMA might also be prevalent. We sought to establish that RWMA can be seen in critically ill patients with normal coronary arteries and to explore reasons for RWMA in this population.

Methods

In this retrospective study, data from the hospital angiography register and the ICU register were collated between 2012 and 2019. Patients were identified who underwent angiography in conjunction with their ICU stay and had RWMA on echocardiography. Patients were divided into either those with non-obstructed or those with obstructed coronary arteries. Cardiac magnetic resonance imaging (cMRI) examinations were reviewed if they had been performed on patients with non-obstructed coronaries.

Results

We identified 53 patients with RWMA and non-obstructed coronary arteries and 204 patients with RWMA and obstructed coronary arteries. Patients with non-obstructed coronary arteries were more often female, younger, and had fewer cardiovascular risk factors. They less commonly had ST elevation, but more frequently had T-wave inversion or serious arrhythmias. Troponin levels were higher in patients with obstructed coronary arteries, but NT-proBNP was similar between the groups. There were no differences in risk-adjusted 90-day mortality between patients with non-obstructed versus obstructed coronary arteries (OR 1.21, [95% CI 0.56–2.64], p = .628). In those with non-obstructed coronary arteries, follow-up echocardiography was available for 38 patients, of whom 30 showed normalization of cardiac function. Of the 14 patients with non-obstructed coronary arteries on whom cMRI was performed, 7 had a tentative diagnosis of Takotsubo syndrome or myocardial stunning; 4 had a myocardial infarction (preexisting in 3 cases); 1 patient had acute myocarditis; 1 patient had post-myocarditis; and 1 patient was diagnosed with dilated cardiomyopathy.

Conclusion

RWMA can be seen to occur in critically ill patients in the absence of coronary artery obstruction. Several conditions can cause regional hypokinesia, and cMRI is useful to evaluate the underlying etiology.  相似文献   
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Huo  Jia  Fu  Lijun  Jin  Mengyuan  Li  Zhaoming  Zhang  Mingzhi 《Investigational new drugs》2022,40(3):537-545
Investigational New Drugs - Background Chemotherapy resistance is a main reason for treatment failure in extranodal NK/T-cell lymphoma (ENKTL). Interleukin-10 (IL-10) is closely related to...  相似文献   
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目的:基于以价值为基础的定价方法,计算核医学学科新增医疗服务项目镭[223 Ra]骨转移瘤治疗的医疗服务价格。为相关新增医疗服务项目的申报和定价打下循证基础,为合理补偿医务人员劳动价值、提升患者服务项目可及性提供依据。方法:采集2021年3—12月使用“镭核素[223 Ra]骨转移瘤治疗资源投入及费用数据采集表”相关数据,开展专家访谈进行系数赋值和基线对照项目确定,得到镭[223 Ra]骨转移瘤治疗服务各个环节的成本和新增服务的价值。结果:镭[223 Ra]骨转移瘤治疗服务按服务特点分为注射前评估、治疗计划、给药、给药后监测、废弃物处理与监测等环节,各环节3地平均人力耗时分别为104分钟、39分钟、25分钟、72分钟和56分钟,中位物耗成本为48.20元,3地总成本(平均人力成本+中位物耗成本)为763.68元。结合系数赋值结果和基线对比项目,得到新增项目的价值为810.19元。结论:运用基于技术难度和风险程度的价值定价理论,计算镭[223 Ra]骨转移瘤治疗新增医疗服务项目的服务价值,建议以价值作为服务定价依据。该定价公式和研究方法不仅可用于其他核医学学科新增服务项目的定价,还适用于现行医疗服务项目的价格动态调整,为未来学科价格工作提供方法学参考。  相似文献   
8.
目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。  相似文献   
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Fu  Xiaoxue  Richards  John E. 《Brain topography》2022,35(4):398-415
Brain Topography - Accurate cortical source localization of event-related potentials (ERPs) requires using realistic head models constructed from the participant’s structural magnetic...  相似文献   
10.
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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