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1.
Marike Gabrielson Mattias Hammarström Magnus Bäcklund Jenny Bergqvist Kristina Lång Ann H Rosendahl Signe Borgquist Roxanna Hellgren Kamila Czene Per Hall 《International journal of cancer. Journal international du cancer》2023,152(11):2362-2372
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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Caroline E. Sloan Judy Zhong Dinushika Mohottige Rasheeda Hall Clarissa J. Diamantidis Leight E. Boulware Virginia Wang 《Seminars in dialysis》2020,33(6):440-448
Caring for patients with end-stage kidney disease (ESKD) in the United States is challenging, due in part to the complex epidemiology of the disease's progression as well as the ways in which care is delivered. As CKD progresses toward ESKD, the number of comorbidities increases and care involves multiple healthcare providers from multiple subspecialties. This occurs in the context of a fragmented US healthcare delivery system that is traditionally siloed by provider specialty, organization, as well as systems of payment and administration. This article describes the role of care fragmentation in the delivery of optimal ESKD care and identifies research gaps in the evidence across the continuum of care. We then consider the impact of care fragmentation on ESKD care from the patient and health system perspectives and explore opportunities for system-level interventions aimed at improving care for patients with ESKD. 相似文献
5.
沙苑子本草考证 总被引:1,自引:0,他引:1
沙苑子为我国常用中药,药用历史悠久。通过查阅本草文献,对沙苑子名称、基原、功效、产地及伪品5个方面进行考证,得知其名称演变大致经过"白蒺藜""沙苑蒺藜""沙苑子"3个阶段;历代本草记载沙苑子基原为扁茎黄芪的干燥成熟种子,古今应用品种基本一致;沙苑子补肾固精功效的记载自宋《本草衍义》起逐渐清晰明确;沙苑子道地产区自宋时起为陕西沙苑,明清时期产地逐渐转到陕西潼关、山西等地,建国后以陕西省为主向北扩散,以陕西潼关为佳;沙苑子建国前有马薸子、色微绿伪品及紫云英子等混伪品,建国后有紫云英、猪屎豆、华黄芪和直立黄芪的种子等混伪品。为沙苑子正本清源,并为其进一步深入开发提供参考。 相似文献
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Sarah E. Henderson Shana A. Hall Jessica M. Callegari James A. Desjardins Sidney J. Segalowitz Karen L. Campbell 《Psychophysiology》2022,59(1):e13947
Recent work suggests that while voluntary episodic memory declines with age, involuntary episodic memory, which comes to mind spontaneously without intention, remains relatively intact. However, the neurophysiology underlying these differences has yet to be established. The current study used electroencephalography (EEG) to investigate voluntary and involuntary retrieval in older and younger adults. Participants first encoded sounds, half of which were paired with pictures, the other half unpaired. EEG was then recorded as they listened to the sounds, with participants in the involuntary group performing a sound localization cover task, and those in the voluntary group additionally attempting to recall the associated pictures. Participants later reported which sounds brought the paired picture to mind during the localization task. Reaction times on the localization task were slower for voluntary than involuntary retrieval and for paired than unpaired sounds, possibly reflecting increased attentional demands of voluntary retrieval and interference from reactivation of the associated pictures respectively. For the EEG analyses, young adults showed greater alpha event-related desynchronization (ERD) during voluntary than involuntary retrieval at frontal and occipital sites, while older adults showed pronounced alpha ERD regardless of intention. Additionally, older adults showed greater ERD for paired than unpaired sounds at occipital sites, likely reflecting visual reactivation of the associated pictures. Young adults did not show this alpha ERD memory effect. Taken together, these data suggest that involuntary memory is largely preserved with age, but this may be due to older adults' greater recruitment of top-down control even when demand for such control is limited. 相似文献
8.
目的 探讨腰硬联合(CSEA)及患者自控镇痛(PCEA)对产程及分娩结局的影响。方法 随机选取2014年1~12月足月待产、无妊娠合并症和并发症初产妇996例,其中503例产妇于活跃期实施CSEA+PCEA镇痛(分娩镇痛组),493例未行分娩镇痛(对照组),分别记录并比较两组产妇各产程时间、子宫收缩、镇痛效果、运动神经阻滞程度、产程中缩宫素的使用率、产后出血率、羊水Ⅲ度污染率、新生儿Apgar评分、产钳助产和剖宫产率。结果 分娩镇痛组第一产程、第二产程较对照组有所延长,差异有统计学意义(P<0.05);第三产程无明显改变;子宫收缩力减弱;分娩镇痛组较对照组镇痛效果显著,差异有统计学意义(P<0.05);运动阻滞程度低;缩宫素使用率、产后出血率、羊水Ⅲ度污染率、及新生儿Apgar评分及产钳助产和剖宫产率两组比较,差异均无统计学意义(P>0.05)。结论 腰硬联合分娩镇痛可能会使第一产程、第二产程延长,对子宫收缩力有一定的影响,但并未增加缩宫素的使用率及产钳助产和剖宫产率,其镇痛效果显著,运动阻滞程度低,对分娩结局无不良影响。 相似文献
9.
目的探讨在进行护理实习教学管理期间新型管理模式应用可行性。方法选择我院2018年1月-2019年2月102例实习护生作为试验对象;数字奇偶法分组后探究每组教学管理模式;对照组(51名):选择传统护理教学管理模式展开;试验组(51名):选择新型护理教学管理模式展开;比较两组护实习护生行为规范合格率、平均业务学习出勤率以及教学满意度评分结果。结果试验组实习护生规范合格率(98.04%)高于对照组(64.71%)(P<0.05);试验组实习护生平均业务学习出勤率(98.04%)高于对照组(62.75%)(P<0.05);试验组实习护生各项教学满意度评分均高于对照组(P<0.05)。结论医院实习护生在接受新型护理实习教学管理后,对于规范合格率的提升,平均业务学习出勤率的提升以及教学满意度评分的提升,均获得显著效果,最终为医院实习护生的学习效率以及护理安全提升奠定了基础。 相似文献
10.
James I. Geller MD Joseph G. Pressey MD Malcolm A. Smith MD Rachel A. Kudgus PhD Mariana Cajaiba MD Joel M. Reid PhD David Hall PhD Donald A. Barkauskas PhD Stephen D. Voss MD Steve Y. Cho MD Stacey L. Berg MD Jeffrey S. Dome MD PhD Elizabeth Fox MD Brenda J. Weigel MD 《Cancer》2020,126(24):5303-5310