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Information on the common carotid artery and cerebral microcirculation can be obtained by micro-ultrasound (µUS). The aim of the study described here was to investigate high-fat diet-induced alterations in vascular parameters in ApoE–/– mice. Twenty-two ApoE–/– male mice were examined by µUS and divided into the standard diet (ApoE–/–SD) and high-fat diet (ApoE–/–HF) groups. The µUS examination was repeated after 4 mo (T1). Carotid stiffness, reflection magnitude and reflection index were measured; the amplitudes of the first (W1) and second (W2) local maxima, the local minimum (Wb) and the reflection index (RIWIA?=?Wb/W1) were assessed with wave intensity analysis. At T1, ApoE–/–HF mice had increased carotid stiffness (1.48 [0.36] vs. 1.88 [0.51]) and reflection magnitude (0.89 [0.07] vs. 0.94 [0.07]) values. Longitudinal comparisons highlighted increases in carotid stiffness for ApoE–/–HF mice (from 1.37 [0.25] to 1.88 [0.51] m/s) but not for ApoE–/–SD mice (from 1.40 [0.62] to 1.48 [0.36] m/s). ApoE–/–HF mice exhibited carotid artery stiffening and increased wave reflections.  相似文献   
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Purpose

High-dose-rate, multicatheter interstitial brachytherapy is technically complex and operator-dependent, requiring lengthy training and specialized skills. Furthermore, until the advent of contouring on computerized tomography (CT) images, difficulties existed in locating the target volume precisely. The present article reports the results of a study that aimed at producing and validating a 3D-printed template to aid in target volume localization for multicatheter interstitial brachytherapy in patients with breast cancer.

Methods and Materials

Thirteen patients, candidates for accelerated partial breast irradiation or boost, were enrolled in the study. The target volume was defined on CT slices, and a template with empty spaces corresponding to the target volume projection on the patient's skin was produced by a 3D printer. The procedure was compared with the standard method followed in our center (1) visually, by assessing overlap between the target volume projections on the patient's skin, (2) by X-ray findings, and (3) by intraclass correlation coefficient.

Results

Visual assessment and X-ray findings showed the 3D-printed target volume always fell within the standard volume in all 13 patients. The intraclass correlation coefficient indicated moderate agreement for both the medial and the lateral skin projections.

Conclusions

The 3-D printed templates constitute a quick, easy, and reliable method to localize the target volume for high-dose-rate interstitial multicathether brachytherapy in patients with breast cancer and can safely be used in clinical practice.  相似文献   
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Identification of deleterious variants in hereditary breast and ovarian cancer (HBOC) susceptibility genes allows for increased clinical surveillance and early detection, and could predict the response to poly (ADP‐ribose) polymerase (PARP) inhibitor in patients with advanced ovarian carcinomas. To determine the prevalence and clinical prediction factors for HBOC syndrome, 882 selected individuals underwent multigene panel testing for HBOC risk assessment during the period from January 2015 to March 2018. Overall, 176 deleterious mutations were observed in 19.50% (n = 172) of individuals. Twenty‐six of 176 mutations could not be retrieved in related public databases and were considered to be novel. Among patients with ovarian cancer, 115 deleterious mutations were identified in 429 patients (48.6%) with significant enrichment for a family history of breast or ovarian cancer syndrome (P < .05). In the breast cancer subgroup, 31 deleterious mutations were identified in 261 patients. Besides BRCA1 (8; 25.8%) and BRCA2 (11; 35.5%), the most frequently occurring genes, an additional 12 deleterious mutations (38.7%) were found in seven other susceptibility genes. Higher mutation incidence (57.9%) was observed in subjects with histories of breast and ovarian cancer. Our results highlighted the genetic heterogeneity of HBOC and the efficiency of a multigene panel in carrying out risk assessment.  相似文献   
37.
Dose-dense adjuvant chemotherapy is standard of care in high-risk early breast cancer patients. However, its role in HER2-positive patients is still uncertain. In this exploratory analysis of the GIM2 trial, we investigated the efficacy of dose-dense chemotherapy in HER2-positive breast cancer patients with or without exposure to trastuzumab. In the GIM2 trial, node-positive early breast cancer patients were randomized to receive four cycles of (fluorouracil)epirubicin/cyclophosphamide followed by four cycles of paclitaxel administered every 2 (dose-dense) or 3 (standard-interval) weeks. After approval of adjuvant trastuzumab, protocol was amended in April 2006 to allow use of trastuzumab for 1 year after chemotherapy completion in HER2-positive patients. The efficacy of dose-dense chemotherapy in terms of disease-free survival (DFS) and overall survival (OS) was assessed according to HER2 status and trastuzumab use. Out of 2,003 breast cancer patients, HER2 status was negative/unknown in 1,551 patients; among the 452 patients with HER2-positive breast cancer, chemotherapy alone or followed by trastuzumab was given to 320 and 132 patients, respectively. Median follow-up was 8.1 years. No significant interaction between HER2 status, trastuzumab use and chemotherapy treatment was observed for both DFS (p = 0.698) and OS (p = 0.708). Nevertheless, there was no apparent benefit in the HER2-positive group treated with trastuzumab (DFS: HR, 0.99; 95% CI 0.52–1.89; OS: HR, 0.95; 95% CI 0.37–2.41). Although dose-dense chemotherapy was associated with a significant survival improvement in high-risk breast cancer patients, its benefit appeared to be smaller (if any) in patients with HER2-positive disease who received adjuvant trastuzumab.  相似文献   
38.
目的分析2018—2019年河北省城市癌症早诊早治项目结直肠癌筛查结果。方法按照河北省城市癌症早诊早治中结直肠癌筛查流程,在石家庄市和唐山市选定社区中年龄40~74岁的当地居民,通过问卷调查后采用国家统一评估模型评估出高危人群,进一步通过结肠镜检查,发现早期结直肠病变,必要时通过病理进行确诊。结果 2018—2019年度,河北省城癌项目共计37849人完成结直肠癌危险因素问卷调查,评估结直肠癌高危人群6938例,总体高危率为18.33%。其中共有1230人参加了结肠镜检查,并完成病理检查465例(37.80%)。进行病理诊断者年龄主要分布在50~64岁。经结肠镜检查及病理诊断,共检出6例(0.49%)结直肠癌患者,其中结肠癌4例(0.33%)、直肠癌2例(0.16%)。结直肠癌癌前病变190例(15.45%),非进展期腺瘤/息肉250例(20.33%),炎性反应性肠道疾病168例(13.66%)。结论开展人群结肠镜筛查可以有效检出结直肠癌和癌前病变,实现结直肠癌的早期发现、早期诊断和早期干预。  相似文献   
39.
随着我国老年人绝对数量的增长以及老龄化加速,骨质疏松症(osteoporosis,OP)已然成为我国需要面对的公共健康问题。近年来对续断防治OP的基础及临床研究成为热点,研究发现川续断皂苷Ⅵ具有较好的防治OP的功效,可以通过多个细胞层面及生物学通路干预骨代谢,从而发挥治疗OP的作用。笔者从续断皂苷Ⅵ对BMSCs、成骨细胞、破骨细胞及相关生物学信号通路的影响来综述续断皂苷Ⅵ防治骨质疏松的研究概况,以期为续断皂苷Ⅵ的基础研究、临床应用及新药开发等提供参考。  相似文献   
40.
神经调控是利用侵入性或非侵入性技术、采用物理性(光、磁、电、超声)或化学性手段改变神经系统功能的生物医学工程技术。过去的30年里,随着人们对脑功能调控机制的深入研究以及现代科学技术的发展,神经调控已经从基本概念转化为临床应用,从单纯技术发展成百亿产业。同时,新兴的神经调控技术也不断涌现。神经调控技术的发展不但为神经科学基础研究提供了全新的研究工具,也为神经系统疾病临床治疗提供了崭新的干预手段。将简述神经调控技术的发展现状和应用领域,阐明不同神经调控技术的作用原理和优劣势,以及展望神经调控技术的发展前景。  相似文献   
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