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21.
ARID1A, one of the subunits in SWI/SNF chromatin remodeling complex, is frequently mutated in gastric cancers with microsatellite instability (MSI). The most frequent MSI in solid‐type poorly differentiated adenocarcinoma (PDA) has been reported, but the SWI/SNF complex status in solid‐type PDA is still largely unknown. We retrospectively analyzed 54 cases of solid‐type PDA for the expressions of mismatch repair (MMR) proteins (MLH1, PMS2, MSH2, and MSH6), SWI/SNF complex subunits (ARID1A, INI1, BRG1, BRM, BAF155, and BAF170) and EBER, and mutations in KRAS and BRAF. We analyzed 40 cases of another histological type of gastric cancer as a control group. The solid‐type PDAs showed coexisting glandular components (76%), MMR deficiency (39%), and complete/partial loss of ARID1A (31%/7%), INI1 (4%/4%), BRG1 (48%/30%), BRM (33%/33%), BAF155 (13%/41%), and BAF170 (6%/2%), EBER positivity (4%), KRAS mutation (2%), and BRAF mutation (2%). Compared to the control group, MMR deficiency and losses of ARID1A, BRG1, BRM, and BAF155 were significantly frequent in solid‐type PDAs. Mismatch repair deficiency was associated with the losses of ARID1A, BRG1, and BAF155 in solid‐type PDAs. In the MMR‐deficient group, solid components showed significantly more frequent losses of ARID1A, BRG1, BRM, and BAF155 compared to glandular components (P = .0268, P = .0181, P = .0224, and P = .0071, respectively). In the MMR‐proficient group, solid components showed significantly more frequent loss of BRG1 compared to glandular components (P = .012). In conclusion, solid‐type PDAs showed frequent losses of MMR proteins and the SWI/SNF complex. We suggest that loss of the SWI/SNF complex could induce a morphological shift from differentiated‐type adenocarcinoma to solid‐type PDA.  相似文献   
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Endolymphatic hydrops features excess endolymph in the membranous labyrinth, and is a marker of Menière's disease. Between the early 1980s and late 2000s, MRI in Menière's disease aimed purely to rule out tumor or malformation as differential diagnoses for the pressure disorder. Progress in high-resolution MRI, however, now enables excess endolymph to be visualized in the membranous labyrinth, differentiating saccule and utricle in Menière's disease and in other clinical presentations such as cochleovestibular schwannoma. More recently, non-visibility of the saccule was demonstrated in a subgroup of Menière's disease patients, and utricle atelectasis in case of uni- or bilateral vestibular areflexia. Endolymph quantification remains highly controversial in terms of grading approach, but a simple semiology based on excess or deficient visualization of endolymph according to the compartment sheds light on the pathophysiological mechanisms of cochleovestibular disorder and may in future allow effective monitoring of medical and surgical treatment.  相似文献   
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Particle size analysis in the pharmaceutical industry has long been a source of debate regarding how best to define measurement accuracy; the degree to which the result of a measurement or calculation conforms to the true value. Defining a “true” value for the size of a particle can be challenging as the output of its measurement will differ because of variations in measurement approaches, instrumental differences and calculation methods. Consequently, for “real” particles, a universal “true” value does not exist and accuracy is therefore not a definable characteristic. Accordingly, precision is then a measure of the ability to reproducibly achieve a measurement of unknown relevance.This article proposes, in place of accuracy, a means to define the “appropriateness” of a measurement in line with the critical quality attributes (CQA) of the material being characterized. The decision as to whether the measurement is correct should involve a link to the CQA; that is, correlation should be demonstrated, without which the measured particle size cannot be defined as a critical material attribute.Correspondingly, methods should also be able to provide sufficient precision to demonstrate discrimination relating to variation in the CQA. The benefits and challenges of this approach are discussed.  相似文献   
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目的 初步评估IMRT对无法手术ⅣA期胸腺瘤的疗效及安全性。方法 回顾分析2010-2017年间15例无法手术接受IMRT的ⅣA期胸腺瘤患者,其中男9例、女6例,中位数59岁。PTV、CTV、GTV放疗剂量分别为50、60、70Gy分15~20次,分析近期疗效、总生存率及不良反应。结果 中位随访时间48个月,近期部分缓解率93%(14/15),1、3、5年总生存率分别为100%、75%、75%,仅1例出现3级血液系统反应。4例死亡患者均为肿瘤相关死亡。结论 初步证明ⅣA期胸腺瘤IMRT疗效较好、安全性高,可作为无法手术治疗的胸腺瘤患者安全、有效的治疗手段。  相似文献   
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BackgroundLymph node recurrences (LNR) from colorectal cancer (CRC) still represent a therapeutic challenge, as standardized recommendations have yet to be established. The aim of this study was to analyze short- and long-term oncological outcomes following resection of LNR from CRC.MethodsAll patients with previously resected CRC who underwent histopathologically confirmed LNR resection in 3 tertiary referral centers between 2010 and 2017 were reviewed. Short- and long-term outcomes were analyzed, mainly recurrence-free and overall survival. Further recurrences following LNR resection were also analyzed.ResultsOverall, 18 patients were included. Primary CRC was left-sided in 16 (89%) patients, staged T3-4 in 15 (83%), N+ in 14 (78%) and presented with synchronous metastases in 8 (43%). Median time interval between primary CRC and LNR resections was 31 months. Performed lymphadenectomies were aortocaval (n = 10), pelvic (n = 7), in hepatic pedicle (n = 3) and mesenteric (n = 1). Four patients had associated liver metastases resection. Three (17%) presented with postoperative complications, of which one Clavien-Dindo 3. Fourteen (78%) patients presented with further recurrences after a mean delay of 9 months, with 36% of patients presenting with early (<6 months) recurrence. Five (36%) patients could undergo secondary recurrence resection and 3 (21%) patients radiotherapy. Median overall survival following LNR resection reached 44 months.ConclusionsCurrent results suggest that LNR resection is feasible and associated with improved survival, in selected patients. Longer time interval between primary CRC resection and LNR occurrence appeared to be a favorable prognostic factor whereas multisite recurrence appeared to be associated with impaired long-term survival.  相似文献   
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《Brain stimulation》2020,13(3):765-773
BackgroundIn healthy subjects (HS), transcranial magnetic stimulation (TMS) demonstrated an increase in motor-evoked potential (MEP) amplitudes during specific linguistic tasks. This finding indicates functional connections between speech-related cortical areas and the dominant primary motor cortex (M1).ObjectiveTo investigate M1 function with TMS and the speech-related cortical network with neuroimaging measures in frontotemporal dementia (FTD), including the non-fluent variant of primary progressive aphasia (nfv-PPA) and the behavioral variant of FTD (bv-FTD).MethodsM1 excitability changes during specific linguistc tasks were examined using TMS in 24 patients (15 with nfv-PPA and 9 with bv-FTD) and in 18 age-matched HS. In the same patients neuroimaging was used to assess changes in specific white matter (WM) bundles and grey matter (GM) regions involved in language processing, with diffusion tensor imaging (DTI) and voxel-based morphometry (VBM).ResultsDuring the linguistic task, M1 excitability increased in HS, whereas in FTD patients it did not. M1 excitability changes were comparable in nfv-PPA and bv-FTD. DTI revealed decreased fractional anisotropy in the superior and inferior longitudinal and uncinate fasciculi. Moreover, VBM disclosed GM volume loss in the left frontal operculum though not in the parietal operculum or precentral gyrus. Furthermore, WM and GM changes were comparable in nfv-PPA and bv-FTD. There was no correlation between neurophysiological and neuroimaging changes in FTD. Atrophy in the left frontal operculum correlated with linguistic dysfunction, assessed by semantic and phonemic fluency tests.ConclusionWe provide converging neurophysiological and neuroimaging evidence of abnormal speech-related cortical network activation in FTD.  相似文献   
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目的探讨接受选择性淋巴结照射(ENI)的食管鳞癌患者预后和失败模式。方法回顾性分析2005年1月至2012年12月河北医科大学第四医院收治的179例符合入组条件的食管鳞癌患者,分析肿瘤局部相关因素预测患者预后的价值,分析影响患者近期疗效、预后的影响因素,并对影响患者总生存率(OS)、无进展生存率(PFS)和复发的指标分别进行单因素和多因素分析。结果全组患者1、3、5年OS和PFS分别为77.1%、40.1%、26.0%和62.6%、30.6%、20.3%。多因素分析结果显示声音嘶哑、cN分期、cTNM分期、GTV-横径(GTV-D)和GTV-体积/长度(GTV-V/L)为影响患者OS的独立性影响因素(P<0.05);声音嘶哑、cTNM分期和近期疗效为影响患者PFS的独立性影响因素(P<0.05)。全组有75例(41.9%)患者出现复发,61例(34.1%)远处转移,其中19例(10.6%)为合并复发和远处转移。75例复发患者中64例(85.3%)患者为单纯食管复发,4例(5.3%)为单纯淋巴结复发,另7例(9.3%)患者为食管合并淋巴结复发。治疗后达完全缓解(CR)的63例患者中有18例患者出现复发,其中仅有2例患者出现淋巴结复发;logistic多因素分析结果显示患者周边组织/器官受侵、GTV-D和近期疗效为影响患者复发的独立性影响因素(P<0.05)。结论食管鳞癌患者接受ENI确实可行,其失败主要模式仍为食管复发;治疗前声音嘶哑、GTV-D和GTV-V/L较大、临床分期较晚和近期疗效不佳为患者预后较差的指标;肿瘤周边组织受侵、GTV-D和近期疗效是影响患者失败的独立性因素。  相似文献   
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