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Serrated polyps (SPs) are precursors to one-third of colorectal cancers (CRCs), with histological subtypes: hyperplastic polyps (HPs), sessile serrated lesions (SSLs) and traditional serrated adenomas (TSAs). The incidence of early-onset CRC before the age of 50 is increasing, with limited understanding of SPs in younger cohorts. Using a large colonoscopy-based cohort, we characterized epidemiologic profiles of SP subtypes, compared to conventional adenomas, with secondary analysis on early-onset polyps. Ninety-four thousand four hundred and twenty-seven patients underwent screening colonoscopies between 2010 and 2018. Demographic, endoscopic and histopathologic characteristics of each polyp subtype were described. High-risk polyps included SSLs ≥10 mm/with dysplasia and conventional adenomas ≥10 mm/with tubulovillous/villous histology/high-grade dysplasia. We examined polyp prevalence with age and compared early- (age < 50) and late-onset polyps (age ≥ 50). Eighteen thousand one hundred and twenty-five patients had SPs (4357 SSLs, 15 415 HPs, 120 TSAs) and 26 699 had conventional adenomas. High-risk SSLs were enriched in the ascending colon (44.1% vs 2.6-35.8% for other locations; P < .003). Early- and late-onset SPs had similar subsite distribution. Early-onset conventional adenomas were more enriched in the distal colon/rectum (51.8% vs 43.4%, P < .001). Multiple conventional adenomas were more represented in late-onset groups (40.8% vs 33.8%, P < .001), with no difference in SSLs. The prevalence of conventional adenomas/high-risk conventional adenomas increased continuously with age, whereas the prevalence of SSLs/high-risk SSLs was stable from age 40 years onwards. A higher proportion of women were diagnosed with early-onset than late-onset SSLs (62.9% vs 57.6%, P = .03). Conventional adenomas, SSLs, early- and late-onset polyps have distinct epidemiology. The findings have implications for improved colonoscopy screening and surveillance and understanding the etiologic heterogeneity of CRC.  相似文献   
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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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In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area.  相似文献   
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IntroductionLung cancer (LC) is usually diagnosed at advanced stages with only a 12% 5-year survival. Trials as NLST and NELSON show a mortality decrease, which justifies implementation of lung cancer screening in risk population. Our objective was to show survival results of the largest LC screening program in Spain with low dosage computed tomography (LDCT).MethodsClinical records from International Early Lung Cancer Detection Program (IELCAP) at Valencia, Spain were analysed. This program recruited volunteers, ever-smokers aged 40-80 years, since 2008. Results are compared to those from other similar sizeable programs.ResultsA total of 8278 participants were screened with at least two-rounds until November 2020. A mean of 6 annual screening rounds were performed. We detected 239 tumours along 12-year follow-up. Adenocarcinoma was the most common histology, being 61.3% at stage I. The lung cancer prevalence and incidence proportion was 1.5% and 1.4%, respectively with an annual detection rate of 0.17. One-year survival and 10-year survival were 90% and 80.1%, respectively. Adherence was 96.84%.ConclusionLargest lung cancer screening in Spain shows that survival is improved when is performed in multidisciplinary team experienced in management of LC, and is comparable to similar screening programs.  相似文献   
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目的探讨对前列腺癌患者采用一体化管理老年综合评估(CGA)护理模式对其心理因素和生活质量的影响。方法选取2020年3月至2021年3月在南京市第一医院就诊,确诊为前列腺癌,且首次行腹腔镜下前列腺癌根治术的患者96例,随机分为对照组、观察1组、观察2组,各32例。对照组为住院后采用常规护理模式进行护理,观察1组为入院后行CGA干预组,观察2组为一体化管理的CGA干预组。三组患者分别在干预前、出院时,进行焦虑自评量表(SAS)、抑郁自评量表(SDS)测评;在干预前、术后30 d,进行生活质量核心量表QLQ-C30(V3.0)和前列腺癌特异性补充量表QLQ-PR25测评。结果出院时,观察2组SAS、SDS评分显著优于对照组及观察1组(P<0.05);术后30 d,观察2组生活质量QLQ-C30、QLQ-PR25评分显著优于对照组及观察1组(P<0.05)。结论一体化管理CGA护理模式可有效改善前列腺癌患者的心理状态,提高其术后生活质量。  相似文献   
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《Molecular therapy》2022,30(1):485-500
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[摘要] 目的 分析新型冠状病毒肺炎疫情(新冠疫情)暴发前、后2个年度,安庆市流行性感冒(流感)流行的强度和特征。方法 在“中国流感监测信息系统”中选取安庆市2019—2021年度监测数据,分析我市新冠疫情发生前、后的流感样病例就诊百分比、病原学阳性率和聚集性疫情的变化。结果 新冠疫情前、后2个年度,流感样病例就诊百分比分别为4.17%和3.78%,差异有统计学意义(χ2=56.652,P=0.000);病原学阳性率分别为23.43%和1.15%,差异有统计学意义(χ2=538.694,P=0.000)。新冠疫情前的流感病毒活动呈现双峰分布,新冠疫情后全年仅检出27份流感病毒阳性样本。结论 新冠疫情中采取的严格非药物预防措施,对流感的季节性特征有重要影响。应通过疫苗接种和非药物预防等措施,做好流感防控工作。  相似文献   
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