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Benign breast disease (BBD) is an established breast cancer (BC) risk factor, but it is unclear whether the magnitude of the association applies to women at familial or genetic risk. This information is needed to improve BC risk assessment in clinical settings. Using the Prospective Family Study Cohort, we used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association of BBD with BC risk. We also examined whether the association with BBD differed by underlying familial risk profile (FRP), calculated using absolute risk estimates from the Breast Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) model. During 176,756 person-years of follow-up (median: 10.9 years, maximum: 23.7) of 17,154 women unaffected with BC at baseline, we observed 968 incident cases of BC. A total of 4,704 (27%) women reported a history of BBD diagnosis at baseline. A history of BBD was associated with a greater risk of BC: HR = 1.31 (95% CI: 1.14–1.50), and did not differ by underlying FRP, with HRs of 1.35 (95% CI: 1.11–1.65), 1.26 (95% CI: 1.00–1.60), and 1.40 (95% CI: 1.01–1.93), for categories of full-lifetime BOADICEA score <20%, 20 to <35%, ≥35%, respectively. There was no difference in the association for women with BRCA1 mutations (HR: 1.64; 95% CI: 1.04–2.58), women with BRCA2 mutations (HR: 1.34; 95% CI: 0.78–2.3) or for women without a known BRCA1 or BRCA2 mutation (HR: 1.31; 95% CI: 1.13–1.53) (pinteraction = 0.95). Women with a history of BBD have an increased risk of BC that is independent of, and multiplies, their underlying familial and genetic risk.  相似文献   
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Despite much attention to the use of biomarkers for predicting Alzheimer disease, little information is available at the individual level. We used the population‐based Mayo Clinic Study of Aging to estimate absolute risk of cognitive impairment by biomarker group. Risk increased with age and any biomarker abnormality. For example, a 75‐year‐old with abnormal amyloid and cortical thinning biomarkers has about a 20% chance of cognitive impairment by age 80 years, whereas with normal biomarkers the chance is <10%. Persons with only one abnormal biomarker had similar intermediate risks. ANN NEUROL 2019;85:155–160.  相似文献   
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Attenuation coefficient estimation has the potential to be a useful tool for placental tissue characterization. A current challenge is the presence of inhomogeneities in biological tissue that result in a large variance in the attenuation coefficient estimate (ACE), restricting its clinical utility. In this work, we propose a new Attenuation Estimation Region Of Interest (AEROI) selection method for computing the ACE based on the (i) envelope signal-to-noise ratio deviation and (ii) coefficient of variation of the transmit pulse bandwidth. The method was first validated on a tissue-mimicking phantom, for which an 18%–21% reduction in the standard deviation of ACE and a 14%–24% reduction in the ACE error, expressed as a percentage of reported ACE, were obtained. A study on 59 post-delivery clinically normal placentas was then performed. The proposed AEROI selection method reduced the intra-subject standard deviation of ACE from 0.72 to 0.39 dB/cm/MHz. The measured ACE of 59 placentas was 0.77 ± 0.37 dB/cm/MHz, which establishes a baseline for future studies on placental tissue characterization.  相似文献   
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Phang  P. Terry 《Abdominal imaging》2019,44(11):3740-3742
Abdominal Radiology -  相似文献   
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Introduction: Chemotherapy is claimed to cause lymphatic drainage damage because of the tumor cell’s apoptosis process. This event might cause decreased marker (radioactive solution and/or blue dye) absorption on sentinel lymph nodes (SLN). In this study, the researchers used methylene blue only and wished to evaluate the methylene blue absorption of the SLNB procedure on early-stage breast-cancer patients after neoadjuvant chemotherapy (NAC). Materials and methods: The method used was the historical cohort study conducted from 2016-2019 in Indonesia. Samples were collected from 117 patients of stage I and II breast cancer with clinically negative axillary lymph nodes, who were then grouped into post-NAC and no-NAC (control group), in which SLNB procedures were conducted on the two groups by using single-method methylene blue. The results of methylene blue absorption were then analyzed by the Chi-square hypothesis test. Results: From the total of 564 early-stage patients who were referred to surgical oncologists, 117 patients were found to meet criteria of inclusion, consisting of the control group (52 patients) and the post-NAC group (65 patents). Of 65 patients who had undergone NAC treatment and SLNB procedure, it was found that 40 patients (61.5%) showed positive blue SLN. Of 52 pre-NAC breast-cancer patients, it was found that 47 patients (90.4%) showed methylene blue absorption on SLN with the p-value of 0.000 (P<0.05, significant). The relative risk value amounted to 0.522. Post-NAC patients had a tendency of decreased absorption of methylene blue. Conclusion: Neoadjuvant chemotherapy can cause the decrease of methylene blue absorption on SLNB procedure.  相似文献   
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