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121.
122.
We report a case documenting fluorodeoxyglucose (FDG) accumulation in cervical, supraclavicular and axillary lymph nodes resulting from acute toxoplasmosis. A 50-year-old Indian female with history of non-Hodgkin's lymphoma (NHL) of left breast, postchemotherapy status, was found to have hypermetabolic right cervical, supraclavicular and axillary lymph nodes on a surveillance FDG positron emission tomography/computed tomography (PET/CT) scan. Her previous two PET/CT scans were unremarkable with no evidence of metabolically active disease. Therefore, a differential diagnosis of relapse of NHL versus infectious/inflammatory pathology was raised in the report. Biopsy of axillary lymph node demonstrated features characteristic of toxoplasmosis. The serological test results were also compatible with acute toxoplasmosis infection. Infective and inflammatory diseases are known to accumulate FDG, resulting in false positives for malignancy. This case demonstrates lymph nodal toxoplasmosis as a potential cause of false positive FDG PET/CT findings in patients with known malignancy and highlights the importance of histopathological and laboratory correlation for the accurate interpretation of FDG PET/CT scans.  相似文献   
123.
Serous uterine cancer is not a feature of any known hereditary cancer syndrome. This study evaluated familial risk of cancers for patients with serous uterine carcinoma, focusing on Lynch syndrome malignancies. Fifty serous or mixed serous endometrial carcinoma cases were prospectively enrolled. Pedigrees were developed for 29 probands and tumors were assessed for DNA mismatch repair (MMR) abnormalities. Standardized incidence ratios for cancers in relatives were estimated. A second-stage analysis was undertaken using data from Gynecologic Oncology Group (GOG)-210. Incidence data for cancers reported in relatives of 348 patients with serous and mixed epithelial and 624 patients with endometrioid carcinoma were compared. Nineteen of 29 (65.5%) patients in the single-institution series reported a Lynch-related cancer in relatives. Endometrial and ovarian cancers were significantly overrepresented and a high number of probands (6 of 29, 20.7%) reported pancreatic cancers. None of the probands' tumors had DNA MMR abnormalities. There was no difference in endometrial or ovarian cancer incidence in relatives of serous and endometrioid cancer probands in the case-control study. Pancreatic cancers were, however, significantly more common in relatives of patients with serous cancer [OR, 2.39; 95% confidence interval (CI), 1.06-5.38]. We identified an excess of endometrial, ovarian, and pancreatic cancers in relatives of patients with serous cancer in a single-institution study. Follow-up studies suggest that only pancreatic cancers are overrepresented in relatives. DNA MMR defects in familial clustering of pancreatic and other Lynch-associated malignancies are unlikely. The excess of pancreatic cancers in relatives may reflect an as yet unidentified hereditary syndrome that includes uterine serous cancers.  相似文献   
124.

Background  

Half of the familial aggregation of ovarian cancer can't be explained by any known risk genes, suggesting the existence of other genetic risk factors. Some of these unknown factors may not be traditional protein encoding genes. MicroRNA (miRNA) plays a critical role in tumorigenesis, but it is still unknown if variants in miRNA genes lead to predisposition to cancer. Considering the fact that miRNA regulates a number of tumor suppressor genes (TSGs) and oncogenes, genetic variations in miRNA genes could affect the levels of expression of TSGs or oncogenes and, thereby, cancer risk.  相似文献   
125.
目的使用超长扫描深度谱域OCT(UL-OCT)研究人眼的角膜和巩膜的弧矢高度和角巩膜缘的形态。方法横断面研究。本研究共纳入40例被检者(80眼),其中男17例,女23例,平均年龄(25.8±2.8)岁。UL-OCT分别拍摄被检者的双眼,应用自行编写的程序量化分析及使用配对t检验比较距离角膜中央各个位置垂直及水平子午线上的角膜及巩膜的弧矢高度,测量角巩膜缘参数并使用重复测量数据方差分析比较各象限参数值的差异。结果被检者左右眼的同侧的角膜中央旁开1.5、3、5、7 mm处的角膜或巩膜的弧矢高度以及角巩膜缘转折点的X、Y轴坐标和该点距离角膜中央3 mm平均切向曲率的差异值之间的差异均无统计学意义。水平子午线上,除X轴坐标之外,其余参数在鼻侧和颞侧的差异均有统计学意义(P<0.05)。垂直子午线上,所有参数在上侧和下侧的差异均无统计学意义。角巩膜缘的转折点的X轴坐标在垂直子午线上较水平子午线上更靠近角膜顶点,Y轴坐标在鼻侧离角膜顶点最远。转折点距离角膜中央3 mm平均切向曲率的差异值在鼻侧最大(P<0.05),其他3个位置之间差异没有统计学意义。结论左右眼同侧的弧矢高度参数无明显差异。角巩膜缘在鼻侧较其他位置表现出更大的转折  相似文献   
126.

Objective

Endometrial stromal sarcoma (ESS) is a rare and indolent form of uterine cancer with ill-defined post-operative treatment guidelines. The goal of this study was to evaluate the rate of recurrence and the effect of various adjuvant treatment modalities.

Methods

Patients with ESS at 4 institutions were identified (1986-2007). Patient demographics, pathology, treatment, and follow-up information were collected. Chi-square statistical analysis was performed.

Results

Forty-three patients with ESS were identified. All patients initially underwent hysterectomy. Twenty-eight (66.7%) had early stage, 12 (28.6%) had advanced stage ESS, and 2 (4.8%) had no staging information. Eight patients received pelvic and or vaginal cuff radiation treatment, with or without chemotherapy. Sixteen of 43 patients experienced a recurrence at an average of 100.5 months. Thirty-three patients were treated with progestin therapy alone or followed expectantly. Complete outpatient records were available for 28 of these patients. Sixteen patients (57%) were followed expectantly while 12 (43%) received progestins. Patients receiving progestins vs. expectant management had a lower rate of recurrence in stage 1 (14.3% vs 38.5%, p = 0.26) and all stages (33% vs 50%, p = 0.38). Twenty-three of 28 (82.1%) patients underwent initial oophorectomy. Eight of 23 (34.8%) had a recurrence, compared to 4 of 5 (80%) in those who retained their ovaries (p = 0.06).

Conclusions

ESS is a rare cancer that is difficult to study. We found removal of the adnexa and post-operative treatment with progestin therapy decreased recurrence rates. These two treatment strategies should be considered in the treatment of patients with all stages of ESS.  相似文献   
127.
目的 研究肠道病毒71型(EV71)3CD蛋白在致病机制中的作用。方法 实验分为对照组、SDLY1组、SDLY107组和SDLY107(1-3CD)组。通过反向遗传技术将弱毒株SDLY1株的3CD蛋白编码区置换到强毒株SDLY107株,形成拯救病毒SDLY107(1-3CD)株。将EV71病毒接种于RD细胞和Vero细胞,于37℃和39.5℃孵育一定时间后,采用MTT试验检测活细胞量,以判断病毒对细胞损伤作用的改变。结果 37℃下,拯救病毒SDLY107(1-3CD)对细胞的损伤作用弱于SDLY107株,但仍强于SDLY1株(P<0.05);39.5℃下,拯救病毒SDLY107(1-3CD)株对细胞的损伤作用较SDLY107株下降(P<0.05),但与SDLY1株的差异无统计学意义(P>0.05)。结论 EV713CD编码区的置换可以改变病毒对细胞的损伤作用,3CD蛋白编码区可能存在影响病毒毒力的位点。这一发现有助于理解EV71的致病机制。  相似文献   
128.
目的:探讨自噬抑制剂3-甲基腺嘌呤(3-methyladenine,3-MA)增强鼻咽癌细胞对放射治疗(放疗)和化学治疗(化疗)敏感性的作用及其相关的分子机制。方法:采用MTT法检测3-MA对细胞的增殖抑制作用;集落克隆形成法检测3-MA对细胞集落克隆形成的影响;Annexin V/PI双染法、线粒体膜电位检测试剂盒(JC-1)、DAPI染色检测细胞凋亡;Western 印迹检测内质网应激相关蛋白葡萄糖调节蛋白78(glucose-regulated protein 78,GRP78)、自噬相关蛋白beclin1和微管相关蛋白1轻链3(microtubule-associated protein 1 light chain 3,LC3)表达。结果:不同体积浓度或剂量的顺铂(cisplatin,DDP)、电离辐射(ionizing radiation,IR)、衣霉素(tunicamycin,TM)、3-MA对鼻咽癌细胞HONE-1均具有增殖抑制作用,且随着体积浓度或剂量的增加和作用时间的延长,对HONE-1细胞增殖抑制作用随之增加。经1.00mmol/L 3-MA预处理细胞后,再次给予6.00 μmol/L DDP,4.00 Gy IR,1.00 μmol/L TM处理,细胞存活率明显降低,均低于单用组,与空白对照组比较差异均有统计学意义(P<0.05)。3-MA增强DDP,IR,TM抑制细胞集落克隆形成作用。用6.00 μmol/L DDP或4.00 Gy IR处理HONE-1细胞24 h后,细胞凋亡率分别为5.8%和6.7%,与阴性对照组比较差异无统计学意义(P>0.05)。JC-1和DAPI染色显示3-MA增强DDP,IR或TM诱导的细胞凋亡作用;Western 印迹结果显示DDP,IR或TM处理组GRP78,beclin1表达呈时间依赖性上调,LC3 I向LC3 II转化,3-MA预处理组beclin1表达明显降低,LC3 I向LC3 II的转化。结论:自噬抑制剂3-MA可增强鼻咽癌细胞对放化疗的敏感性,其机制可能与3-MA抑制内质网应激诱导的自噬所产生的保护作用相关。  相似文献   
129.
目的:分析鱼刺伤肉芽肿患者的临床特点、病理及分子生物学检测情况。方法:对我院门诊确诊的20例鱼刺伤肉芽肿患者临床资料进行回顾性分析。结果:20例患者中16例(80%)患者发病前有外伤史且与水产品或水有接触,4例(20%)无明显诱因;所有患者皮损发生于上肢,17例患者单侧发病,3例双侧发病;临床表现以原发皮疹、浅表破溃或多发结节为主。20例患者病理组织检查者均提示感染性肉芽肿;TB-IGRA阳性率为70%。17例(85%)患者于治疗后6个月内痊愈,1例治疗10个月后痊愈,2例正在随访中。结论:本文中患者海分枝杆菌感染多与日常接触水产品有关;临床以单侧发病为主;TB-IGRA阳性检出率高。  相似文献   
130.
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