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11.
Sudden death due to anomalous aortic origin of a coronary artery is far less common among young children in the absence of exercise stress. This report describes the case of a 2-year-old boy with a lower respiratory tract infection who suffered sudden cardiac arrest in his bed at home. The autopsy revealed that the left coronary artery (LCA) originated from the right sinus of Valsalva with an acute angle takeoff and traveled between the aorta and the pulmonary trunk (an interarterial course). Upon histological examination, the LCA, before reaching its major branches, was located adjacent to the outside of the aortic wall without an intramural passage, and the arterial wall was composed almost exclusively of elastic fibers without media containing smooth muscle cells throughout the entire length of the abnormal running. Screening tests for respiratory virus infection detected enterovirus in the lung tissue. In association with an acute angle takeoff and interarterial course, the wall structure with highly abundant elastic fibers that are more flexible tissues among blood vessel components might suggest their vulnerability to compression during the great vessels’ systolic expansion in the sympathetic activation induced by the viral infection, leading to fatal myocardial ischemia without physical exertion.  相似文献   
12.
This review outlines the important oral implications of tobacco use. The lining of the mouth (oral mucosa), if exposed to tobacco and its products in a susceptible individual, can develop benign, potentially malignant, and malignant tumours. Treatment and prognosis depend on tumour type, how early it is detected, its size and site in the oral cavity and whether it has spread. Advanced oral squamous cell carcinoma (OSCC) has a 20% 5-year survival rate. Tobacco use also increases the risk of periodontitis, peri-implantitis, caries, alveolar osteitis and halitosis. Although less life threatening than OSCC, these tobacco related conditions create a substantial financial and health burden for individuals and society. Dental practitioners routinely examine the oral cavity for signs of mucosal and tooth changes, are experienced in recognising variations from normal and have established management and referral pathways. They are also ideally positioned to provide brief interventions to assist their patients to quit smoking.  相似文献   
13.

Background

Multiparametric magnetic resonance imaging (mpMRI) undoubtedly affects the diagnosis and treatment of localized prostate cancer (CaP). However, clinicians need a better understanding of its accuracy and limitations in detecting individual CaP foci to optimize management.

Objective

To determine the per-lesion detection rate for CaP foci by mpMRI and identify predictors of tumor detection.

Design, setting, and participants

We carried out a retrospective analysis of a prospectively managed database correlating lesion-specific results from mpMRI co-registered with whole-mount pathology (WMP) prostatectomy specimens from June 2010 to February 2018. Participants include 588 consecutive patients with biopsy-proven CaP undergoing 3-T mpMRI before radical prostatectomy at a single tertiary institution.

Outcome measurements and statistical analysis

We measured mpMRI sensitivity in detecting individual CaP and clinically significant (any Gleason score ≥7) CaP foci and predictors of tumor detection using multivariate analysis.

Results and limitations

The final analysis included 1213 pathologically confirmed tumor foci in 588 patients with primarily intermediate- (75%) or high-risk (12%) CaP. mpMRI detected 45% of all lesions (95% confidence interval [CI] 42–47%), including 65% of clinically significant lesions (95% CI 61–69%) and nearly 80% of high-grade tumors. Some 74% and 31% of missed solitary and multifocal tumors, respectively, were clinically significant. The majority of missed lesions were small (61.1% ≤1 cm); 28.3% were between 1 and 2 cm, and 10.4% were >2 cm. mpMRI missed at least one clinically significant focus in 34% of patients overall, and in 45% of men with multifocal lesions. On multivariate analysis, smaller, low-grade, multifocal, nonindex tumors with lower prostate-specific antigen density were more likely to be missed. Limitations include selection bias in a prostatectomy cohort, lack of specificity data, an imperfect co-registration process, and uncertain clinical significance for undetected lesions.

Conclusions

mpMRI detects less than half of all and less than two-thirds of clinically significant CaP foci. The moderate per-lesion sensitivity and significant proportion of men with undetected tumor foci demonstrate the current limitations of mpMRI.

Patient summary

Magnetic resonance imaging of the prostate before surgical removal for prostate cancer finds less than half of all individual prostate cancer tumors. Large, solitary, aggressive tumors are more likely to be visualized on imaging.  相似文献   
14.
目的 讨论胰腺胃肠间质瘤的临床病理特征、预后影响因素及基因突变特征。方法 回顾性分析2010年5月至2018年10月西南医科大学附属医院确诊的4例胰腺胃肠间质瘤,并通过Pubmed及国内主要数据库检索国内外文献,进行文献复习及统计分析。结果 国内外报道病例共55例,合并本次报道共59例。男性30例,女性29例,最常见临床首发症状为腹部疼痛或不适有38例(64.4%)、腹部肿块10例(16.9%)、体检发现或其他症状11例(18.7%);53例具有完整的影像学资料及组织学分型,影像学CT检查示肿瘤为不均匀低密度影,呈囊实性21例(39.7%)、呈实性20例(37.7%)、呈囊性12例(22.6%);最常见组织学类型是梭形细胞为主型44例(83.0%)、混合型7例(13.2%)、上皮细胞为主型2例(3.8%)。5年总存活率及无疾病存活率分别为79.7%及39.3%;单因素及多因素分析均显示,核分裂象>5个/50HPF是影响病人术后复发转移的独立因素(P均<0.05)。10例基因突变病人中9例(90.0%)为c-kit基因突变,1例(10.0%)为PDGFRα基因突变。结论 胰腺胃肠间质瘤临床症状缺乏特异性,通常发现时肿瘤体积较大,多数病人具有高度风险性,且核分裂象>5个/50HPF是影响预后的独立因素,以c-kit基因突变多见。  相似文献   
15.
Purpose: Numerous studies have reported a robust relationship between early phonological awareness (PA) and subsequent reading achievement, in addition to the critical role of the alphabetic principle in predicting and supporting later reading and spelling development. Given this association, there has been an increasing push to teach these skills to young children prior to word level reading and spelling instruction. This study evaluated the effectiveness of the Cracking the Code (CtC) program with students aged 3;8–5;4. CtC is a teacher-implemented program, designed to explicitly target PA skills and alphabet knowledge.

Method: A pre-test post-test group design was used to evaluate the effectiveness of the program. Four schools in metropolitan Western Australia were randomly assigned to either the control or experimental condition within a parallel groups design. The control group participated in an alternative program matched for duration and frequency, targeting semantics and grammar.

Result: The children in the experimental condition improved significantly more in PA, alphabet knowledge and non-word reading, and spelling after intervention than the control group.

Conclusion: These findings demonstrate that classroom-based, teacher-delivered PA and alphabet knowledge instruction can be effective for 3;8–5;4 year-olds.  相似文献   

16.
目的:探讨滤泡状甲状腺癌骨转移的临床特征和治疗方法。方法:回顾性分析1例以左侧锁骨病理性骨折及骨痛为首发症状的滤泡状甲状腺癌患者的临床影像学资料、病理学资料,随访治疗效果,并复习相关文献。结果:患者左侧甲状腺肿物考虑为滤泡状甲状腺癌。C5、T10椎体、左侧锁骨考虑为转移癌。行左侧锁骨部分切除术,术后病理提示:滤泡状甲状腺癌骨转移。结论:对以病理性骨折和骨痛为主要症状的滤泡状甲状腺癌,影像学与组织活检相结合有利于降低误诊率,治疗方案取决于对患者局部病灶和全身状况的全面评估。  相似文献   
17.
18.
X-linked lymphoproliferative disease (XLP) is a rare immunodeficiency disease characterized by severe immune disorder and extreme vulnerability to Epstein-Barr virus (EBV) infections. Here we report a 14-month-old Chinese boy presenting with fulminant infectious mononucleosis (FIM) following EBV infection, and died of hepatic failure within one week of disease progression. Postmortem examination revealed icterus, ascites, extensive enlarged mesenteric lymph nodes and hepatosplenomegaly. Histopathological examination showed diffuse proliferation of cytotoxic T lymphoid cells and hemophagocytosis in multiple organs. The family history revealed his brother had died under similar circumstances at 5 five years of age. The cause of death of the boy was ascribed to XLP. To the best of our knowledge, there is few autopsy-confirmed XLP case in the forensic practice. The complicated manifestations and systemic pathological changes should be well recognized by clinicians and forensic pathologists.  相似文献   
19.
20.
目的研究胃肠道间质瘤的MSCT表现与病理危险程度分级的关系。方法此项研究对象为医院2014年1月—2018年12月经过手术、病理等确诊为胃肠道间质瘤的患者,共计50例,对其MSCT表现进行回顾分析,评估肿瘤最大径、生长方式等和病理危险程度分级关系。结果50例胃肠道间质瘤患者中,胃部18例,胃肠道外5例,肠道27例;病理分级中低度危险7例,中度危险8例,重度危险35例。不同危险程度肿瘤出现的位置和强化情况差异无统计学意义(P>0.05),肿瘤生长方式、形态、转移情况等对比差异有统计学意义(P<0.05)。结论胃肠道间质瘤的MSCT表现有特性,和病理危险程度分级密不可分,对治疗、确定预后等有积极影响。  相似文献   
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