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81.
The prevalence of overweight and obesity and their health-related problems have been increasing.Obesity is increasingly recognized as a risk factor in different types of cancer in humans.The mechanisms supporting the link between obesity and cancer development have not been fully understood.Leptin,a circulating cytokine produced by adipocytes,may influence prostate cancer(PCa)progression in different ways.Body mass index seems to be an unreliable predictor for the development of PCa,but its influence on progression and poor oncological outcomes seems to be clear.Given the fact that abdominal fat is the most metabolically active fat,with different metabolic and paracrine effects,related anthropometric measurements may lead to a better estimation of PCa risk.Metabolically active periprostatic abdominal fat may also play an important role in releasing cytokines and growth factors that may promote tumor cell proliferation or even create a favorable environment for aggressive tumor biology.Different imaging measurements,e.g.,periprostatic adipose tissue(PPAT)thickness,may be significant predictors of PCa.Several genes in the PPAT of obese men have been identified to contribute to chronic immuno-inflammatory responses which eventually lead to cell cycle alterationwith oncological potential.In vitro studies showed the importance of PCa and its interaction with its microenvironment particularly in patients with aggressive PCa.Different types of cytokines,such as interleukin-6,may promote a tumorigenic microenvironment.This article endeavors to review the current literature on the association of PPAT with aggressive tumor biology in PCa.  相似文献   
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The identification of causal BRCA1/2 pathogenic variants (PVs) in epithelial ovarian carcinoma (EOC) aids the selection of patients for genetic counselling and treatment decision-making. Current recommendations therefore stress sequencing of all EOCs, regardless of histotype. Although it is recognised that BRCA1/2 PVs cluster in high-grade serous ovarian carcinomas (HGSOC), this view is largely unsubstantiated by detailed analysis. Here, we aimed to analyse the results of BRCA1/2 tumour sequencing in a centrally revised, consecutive, prospective series including all EOC histotypes. Sequencing of n = 946 EOCs revealed BRCA1/2 PVs in 125 samples (13%), only eight of which were found in non-HGSOC histotypes. Specifically, BRCA1/2 PVs were identified in high-grade endometrioid (3/20; 15%), low-grade endometrioid (1/40; 2.5%), low-grade serous (3/67; 4.5%), and clear cell (1/64; 1.6%) EOCs. No PVs were identified in any mucinous ovarian carcinomas tested. By re-evaluation and using loss of heterozygosity and homologous recombination deficiency analyses, we then assessed: (1) whether the eight ‘anomalous’ cases were potentially histologically misclassified and (2) whether the identified variants were likely causal in carcinogenesis. The first ‘anomalous’ non-HGSOC with a BRCA1/2 PV proved to be a misdiagnosed HGSOC. Next, germline BRCA2 variants, found in two p53-abnormal high-grade endometrioid tumours, showed substantial evidence supporting causality. One additional, likely causal variant, found in a p53-wildtype low-grade serous ovarian carcinoma, was of somatic origin. The remaining cases showed retention of the BRCA1/2 wildtype allele, suggestive of non-causal secondary passenger variants. We conclude that likely causal BRCA1/2 variants are present in high-grade endometrioid tumours but are absent from the other EOC histotypes tested. Although the findings require validation, these results seem to justify a transition from universal to histotype-directed sequencing. Furthermore, in-depth functional analysis of tumours harbouring BRCA1/2 variants combined with detailed revision of cancer histotypes can serve as a model in other BRCA1/2-related cancers. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.  相似文献   
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王青  牛广华  田增民 《医学争鸣》1999,20(4):367-368
0引言老年性白内障严重影响着老年人的生活质量.手术是根治本病的最佳方法.现将我院1998-01~1998-11经B超检查并经手术证实的129例,共258只眼,223只老年性白内障的结果及声像图特点报告如下.旨在探讨B超在诊断该病中的应用价值及对手术的...  相似文献   
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The normal anatomy of the nasopharynx and floor of the middle cranial fossa was analyzed with magnetic resonance (MR) imaging. MR images from five healthy volunteers were correlated with whole-organ cryomicrotome sections from three cadavers. Anatomic connections exist between the paranasopharyngeal spaces and the surface structures of the skull base. These anatomic connections include the intimate relationship between the eustachian tube and the pharyngobasilar fascia, the attachment of the muscles of mastication and deglutition to the skull base, and vascular and nervous structures in the foramina. The inherent contrast between the soft tissues of the nasopharynx and related structures and the bone of the floor of the middle cranial fossa allowed excellent visualization of these anatomic connections.  相似文献   
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Sonograms of seven patients with extratesticular lesions are presented because of their relatively rare occurrence or unusual sonographic pattern. The sonographic appearance of a malignant extratesticular liposarcoma is described. Infected sebaceous glands and slow-growing malignant tumors of the spermatic cord are demonstrated as possible problems in differential diagnosis. Extratesticular septated cysts or fluid collections surrounding the spermatic cord are documented as complications in hemophilia and acute pancreatitis. These entities are presented because of their differential diagnostic challenge compared with more common disorders such as infected hydroceles and hernias.  相似文献   
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To establish criteria for the differentiation of benign and malignant tumors of the parotid gland using color Doppler sonography (CDS) and pulsed Doppler sonography (PDS) we examined 37 patients with parotid tumors by gray-scale ultrasound, CDS, and PDS. Tumor vascularization displayed by CDS was graded subjectively on a 4-point scale (0 = no vascularization, 3 = high vascularization). From the Doppler spectrum, the highest systolic peak flow velocity, the resistive index (RI), and the pulsatility index (PI) were calculated. There were 11 malignant and 26 benign tumors. Tumor vascularization by CDS was grade 0 or 1 in 88.5 % of benign lesions, whereas it was grade 2 or 3 in 82 % of malignant lesions (P < 0.0001). The highest systolic peak flow velocity was statistically significantly higher in malignant lesions than in benign lesions. Using a threshold systolic peak flow velocity of 25 cm/s, sensitivity was 72 % and specificity was 88 % for the detection of a malignant tumor. Evaluation of tumor vascularization by CDS and PDS cannot differentiate between benign and malignant parotid tumors with certainty. However, high vascularization and high systolic peak flow velocity in tumor vessels should raise the suspicion of malignancy, even if tumor morphology on gray-scale sonography indicates a benign lesion. Received 5 February 1998; Accepted 5 March 1998  相似文献   
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