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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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水分活度(简称a;)是食品和化妆品行业快速评价微生物风险和产品稳定性的重要指标之一。基于a;的原理深入分析a;对微生物生长的作用,综述目前药学研究中a;的应用现状,并借鉴食品、化妆品行业中a;的测量方法及应用方案,探讨a;用于中药临方制剂微生物风险控制的应用前景。此外,由于中药临方制剂对时限性的特殊要求,常规的细菌检测过程耗时过长,不能与其特性相适应,因而a;的引入将大大降低产品微生物检验的时限压力,有助于提高制剂的安全控制能力,为中药临方制剂的开发和应用提供高效可行的质控方案。  相似文献   
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  目的  比较热消融与手术切除治疗异时性结直肠癌肝转移(colorectal liver metastasis, CRLM)的疗效,探讨热消融的潜在合适人群。  方法  回顾性收集2007年11月–2021年1月在中国医学科学院肿瘤医院接受根治性治疗的319例CRLM患者资料,根据治疗方法的不同,分为热消融组和手术切除组。运用倾向性评分匹配(propensity scoring match, PSM)平衡患者基线资料。运用Cox回归分析确定影响患者复发及生存的危险因素。两组间进行生存分析。  结果  按照1∶1比例,PSM后热消融组和手术切除组各匹配92例患者。热消融组中位总生存时间为49(95%置信区间37~76)个月,短于手术切除组(P<0.01)。多因素Cox回归分析提示原发肿瘤T分期、转移瘤数目、转移瘤最大直径、术前血清癌胚抗原水平及治疗方式是影响总生存时间的独立危险因素。与手术切除组相比,热消融组肝脏复发率较高(59.8% vs. 23.9%,P<0.01),无病生存期较短(10个月 vs. 33个月,P<0.01),但住院时间更短(7.0 d vs. 14.0 d,P<0.01)。亚组分析使用匹配前的319例样本进行,显示早期复发的患者接受热消融和手术切除的中位总生存期相当(29个月 vs. 42个月,P=0.35);非早期复发的患者接受热消融治疗的中位总生存期短于手术切除组(P<0.01)。  结论  手术切除CRLM的疗效优于热消融治疗,但在早期复发患者中两者疗效相当。  相似文献   
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目的:阐述动物智能在军事学的应用及意义。方法:以学术论文、新闻、报纸、智库报告等作为信息源,综合研究国外动物智能军事应用实例及内在关联,描述动物智能在未来战场应用场景。结果:动物智能军事应用主要是动物特殊能力的军事应用和动物智能的仿生武器应用。结论:动物部队、仿生作战部队和动物战术是未来战争不可忽视的重要组成部分,动物智能的隐匿、灵活、多变等特点正逐渐被广泛应用于战场。  相似文献   
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目的探讨改良张力支具对肱骨髁间骨折患者术后功能康复的临床效果评价。 方法回顾性分析本院采用切开复位内固定术治疗的40例肱骨髁间骨折患者的资料。单纯采用普通固定支具进行功能锻炼的为对照组(21例),采用改良张力支具进行功能锻炼的为观察组(19例)。比较两组患者术后去除支具和末次随访时肘关节屈曲度、肘关节背伸度、前臂旋前度、前臂旋后度和Mayo肘关节功能评分,以评定改良张力支具的疗效。 结果所有患者术后均获得随访,平均随访13.79个月。观察组与对照组相比,术后去除支具时肘关节屈伸活动度[(104.47±12.37)° vs.(88.85±8.10)°,P<0.001],差异有统计学意义;肘关节旋转活动度[(140.31±16.87)° vs.(135.66±12.86)°,P=0.331],差异无统计学意义;肘关节Mayo评分[(78.84±5.04)分vs.(73.80±4.46)分,P=0.002],差异有统计学意义。末次随访时肘关节屈伸活动度[(107.52±12.30)° vs.(93.00±8.47)°,P<0.001],差异有统计学意义;肘关节旋转活动度[(141.42±17.02)° vs.(137.19±12.80)°,P=0.37],差异无统计学意义;肘关节Mayo评分[(80.15±5.24)分vs.(74.95±4.18)分,P=0.001],差异有统计学意义。 结论术后使用改良张力支具可以改善肱骨髁间骨折患者的屈伸活动度和肘关节功能。  相似文献   
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本文报道1例原发于腰臀部的细粒棘球蚴病病例。该病例初诊时被误诊为“皮下脓肿”,后经影像学检查及抗棘球蚴抗体试验得以确诊。本病例报道旨在提高临床医师对细粒棘球蚴病的认识,避免和减少误诊、漏诊。  相似文献   
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