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The incidence of breast cancer across the world has been on the rise in recent decades. Because identified risk factors can only explain a relatively small portion of the cases, environmental exposure to organic pollutants is suspected to play a role in breast cancer etiology. Polychlorinated biphenyls (PCBs) are among the most abundant pollutants, and the impact of their exposure on breast cancer risk has been extensively studied in recent decades. However, the results of most epidemiologic studies do not support an association between PCB exposure and breast cancer risk. We hypothesized that the effects of PCBs on breast cancer might have been undervalued for reasons such as insufficient recognition of the confounding effects of several factors and lack of attention on the innate heterogeneity of PCB mixtures or breast cancer. After reviewing the evidence in the existing literature, we concluded that early life exposure, known risk factors of breast cancer, and impact of exposure to other pollutants are the main sources of confounding effects and have potentially masked the associations between PCBs and breast cancer. Because PCBs are mixtures of congeners with varied properties, and because breast cancers of different subtypes are etiologically distinct diseases, the absence of stratified subgroup analysis on individual PCBs and patients with specific biological subtypes and insufficient attention paid to the results of these subgroup analyses may result in an underestimation of the correlations between PCBs and breast cancer. In future studies, these factors must be taken into consideration when exploring the effect of PCB exposure on breast cancer risk.  相似文献   
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BACKGROUND Pathological complete response(pCR) is rare in hormone receptor-positive(HR+)HER2-negative breast cancer(BC) treated with either endocrine therapy(ET) or chemotherapy. Radical resection of locoregional relapse, although potentially curative in some cases, is challenging when the tumor invades critical structures.The oral cyclin-dependent kinase 4/6 inhibitor palbociclib in combination with ET has obtained a significant increase in objective response rates and progression-free survival in patients with advanced BC and is now being evaluated in the neoadjuvant setting. We present a clinical case of a patient with an inoperable locoregional relapse of HR+ HER2-negative BC who experienced p CR after treatment with palbociclib.CASE SUMMARY We report the clinical case of a 60-year-old patient who presented with an inoperable locoregional relapse of HR+, HER2-negative BC 10 years after the diagnosis of the primary tumor. During a routine follow-up visit, breast magnetic resonance imaging and positron emission tomography/computed tomography revealed a 4-cm lesion in the right subclavicular region, infiltrating the chest wall and extending to the subclavian vessels, but without bone or visceral involvement. Treatment was begun with palbociclib plus letrozole, converting the disease to operability over a period of 6 mo. Surgery was performed and a p CR achieved. Of note, during treatment the patient experienced a very uncommon toxicity characterized by burning tongue and glossodynia associated with dysgeusia, paresthesia, dysesthesia, and xerostomia. A reduction in the dose of palbociclib did not provide relief and treatment with the inhibitor was thus discontinued, resolving the tongue symptoms. Laboratory exams were unremarkable. Given that this was a late relapse, the tumor was classified asendocrine-sensitive, a condition associated with high sensitivity to palbociclib.CONCLUSION This case highlights the potential of the cyclin-dependent kinase 4/6 inhibitor plus ET combination to achieve pCR in locoregional relapse of BC, enabling surgical resection of a lesion initially considered inoperable.  相似文献   
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BackgroundMenopausal symptoms have negative effects on the aspects of quality of life and impose a high cost on the health system. In traditional Persian medicine, pomegranate is recommended to alleviate menopausal symptoms.Material and methodsA randomized double-blind placebo-controlled trial was performed among 78 healthy women. Participants were interviewed three times: Before receiving the supplement/placebo, after completing the treatment, and after 3 weeks with no intervention. They filled out the demographic information sheet, modified-Kupperman index, and Menopause-Specific Quality of Life (MENQOL) questionnaires.ResultsThe mean scores of the modified-Kupperman index and MENQOL characteristics before and after the treatment and after the follow-up period were significantly different between pomegranate and placebo groups in both modified-Kupperman and MENQOL scores (p < 0.001).ConclusionThis study demonstrated that 4 weeks' treatment with the pomegranate supplement significantly ameliorates the irritating symptoms of menopause and improves the quality of life in menopausal women even after 4 weeks' medicine deprivation.  相似文献   
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目的调查全国235家实验室红细胞沉降率(ESR)参考区间和医学决定水平的现状。方法利用基于Web方式的室间质量评价软件系统,收集参加2014年ESR参考区间调查室间质量评价计划的实验室与参考区间和医学决定水平有关的结果。使用SPSS 13.0软件对所有参加的实验室结果进行分析,按照仪器对各实验室进行分组进行参考区间和医学决定水平的统计描述。结果参加调查ESR参考区间的实验室数量为235家,其中96家上报了医学决定水平。参考区间来源中,比例最高的为《全国临床检验操作规程》(80.85%),接下来依次为教科书(8.51%)、仪器试剂厂家说明书(6.38%)、实验室自己确定(2.98%)和其他。医学决定水平的来源中,最多的也是《全国临床检验操作规程》(75.00%),其次为仪器试剂厂家说明书(15.63%)。仅有45.11%和46.88%的参与实验室在使用参考区间和医学决定水平前对其进行了验证。分别有168家和72家实验室按照性别对ESR参考区间和医学决定水平进行了区分。男、女和未分组的参考区间上限和医学决定水平在不同仪器组无明显差异(P0.05)。结论我国ESR参考区间和医学决定水平的现况不尽如人意,目前急需一致的国家标准来指导实验室制订适当的ESR参考区间和医学决定水平。  相似文献   
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目的探讨调肝运脾汤在腹泻型肠易激综合征治疗中的应用价值。方法在医院2014年3月—2016年1月期间诊治的腹泻型肠易激综合征患者中抽取56例作研究对象,并通过随机抽签方式分组,对照组(28例)采用匹维溴铵片治疗,治疗组(28例)在对照组常规用药基础上加用调肝运脾汤治疗,对比两组患者治疗前后的中医症状积分、血清5-羟色胺水平变化。结果治疗组患者治疗后的腹痛、腹泻、腹胀、神疲乏力、纳呆症状积分均低于对照组(均P0.01);治疗组血清内5-羟色胺水平为(65.17±4.96)ng/ml,低于对照组的(82.74±9.48)ng/ml(P0.05)。结论调肝运脾汤在腹泻型肠易激综合征治疗中的应用价值显著,可明显改善患者临床症状,纠正其血清5-羟色胺水平,可作为腹泻型肠易激综合征患者的理想用药。  相似文献   
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The present work deals with the investigation of the electrochemical reduction of silver thiosulphate (1,2-Ag(S2O3)23?), thiocyanate (1,3-Ag(SCN)32?) and 1,8-dihydroxy-3,6-dithiaoctane (1,2-Ag(DTO)2+) complexes. The influence of the ligand type on the charge transfer rate is explained by the changing positions of the density distributions of electronic energy levels of the three complexes. The basics for this approach are the theories of energy band models (EBMs). An experimental methodology is developed to determine the energy density distributions. A Ti/TiO2 substrate, obtained by galvanostatically anodising Ti, is put forward as an appropriate substrate for this investigation, and its semiconducting properties are determined. On this substrate, charge transfer (CT) controlled currents can be measured in a sufficiently large potential domain for the three systems. A method of pre-plating is optimised such that the overall semiconducting character of the substrate is kept during the monitoring of the (quasi-)stationary current/voltage diagrams. The active surface areas, necessary for the calculation of the current density/potential curves, are calculated. The positions of the energy density distributions, obtained by the derivation of the current density/voltage diagrams, of the three complexes, show that thiosulphate exhibits the smallest density of accepting energy levels in the given potential domain. For potentials above 0.5 V vs. SCE, the DTO complex has the largest density of vacant energy levels, but for lower potentials the situation is reversed.  相似文献   
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激素替代疗法治疗女性灼口综合征的临床观察   总被引:2,自引:1,他引:2  
目的 :观察尼尔雌醇治疗女性灼口综合征的临床效果。方法 :采用尼尔雌醇辅以孕激素的雌激素替代疗法治疗已停经的女性灼口综合征患者。结果 :激素治疗组与维生素治疗组相比有显著性差异 (P <0 .0 1)。结论 :舌感觉异常多发生在妇女更年期 ,内分泌紊乱起着重要作用 ,激素替代疗法可以明显缓解症状  相似文献   
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