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71.
目的锯齿状腺瘤被公认为结直肠癌的癌前病变,锯齿状通路被认为是可以独立发展成结直肠癌的重要通路,但目前对于锯齿状腺瘤恶变的相关危险因素还知之甚少。本文旨在分析锯齿状腺瘤在结直肠中的分布特点及潜在恶变因素。方法采用病例对照研究方法,回顾性收集2017年4月至2019年7月期间在中国医学科学院肿瘤医院行肠镜检查并经病理诊断为锯齿状腺瘤患者的临床资料,排除同时具有两种及以上病理类型病变的患者。总结锯齿状腺瘤的临床特征,并进行单因素和Logistic多因素回归分析,探讨锯齿状腺瘤发生恶变的影响因素。结果共在28730例行肠镜检查患者中,发现311例(1.08%)锯齿状腺瘤患者,共发现锯齿状腺瘤372枚。按WHO分类,无蒂锯齿状腺瘤/息肉22枚(5.9%),传统锯齿状腺瘤84枚(22.6%),未分类锯齿状腺瘤266枚(71.5%)。病理结果显示:无异型增生病变106枚(28.5%),低级别上皮内瘤变病变228枚(61.3%),高级别上皮内瘤变或癌变38枚(10.2%)。病变长径<10 mm有204枚(54.8%),≥10 mm有168枚(45.2%);病变位于左半结直肠238枚(64.0%),右半结肠134枚(36.0%)。内镜下大体分型:扁平型16枚(4.3%),无蒂型174枚(46.8%),亚蒂型117枚(31.5%),带蒂型59枚(15.9%)。窄带成像国际结直肠内镜(NICE)分型:Ⅰ型85枚(22.8%),Ⅱ型280枚(75.3%),Ⅲ型4枚(1.1%)。单因素分析显示,病变大小、病变位置、病变部位及不同WHO分类与结直肠锯齿状腺瘤发生恶变有关(均P<0.05);不同NICE分型的锯齿状腺瘤,其恶变率的差异亦有统计学差异(P=0.001)。多因素分析结果显示,病变长径≥10 mm(OR=6.699,95%CI:2.843~15.786)以及病变位于左半结直肠(OR=2.657,95%CI:1.042~6.775)是结直肠锯齿状腺瘤发生恶变的独立危险因素。结论锯齿状腺瘤主要位于左半结直肠,当病变长径≥10 mm或病变位于左半结直肠时,易发生恶变。  相似文献   
72.
BackgroundHepatocellular carcinoma (HCC) is one of the most common causes of cancer worldwide. Although many studies have focused on oncogene characteristics, the genomic landscape of Chinese HCC patients has not been fully clarified.MethodsA total of 165 HCC patients, including 146 males and 19 females, were enrolled. The median age was 55 years (range, 27–78 years). Corresponding clinical and pathological information was collected for further analysis. A total of 168 tumor tissues from these patients were selected for next-generation sequencing (NGS)-based 450 panel gene sequencing. Genomic alterations including single nucleotide variations (SNV), short and long insertions and deletions (InDels), copy number variations, and gene rearrangements were analyzed. Tumor mutational burden (TMB) was measured by an algorithm developed in-house. The top quartile of HCC was classified as TMB high.ResultsA total of 1,004 genomic alterations were detected from 258 genes in 168 HCC tissues. TMB values were identified in 160 HCC specimens, with a median TMB of 5.4 Muts/Mb (range, 0–28.4 Muts/Mb) and a 75% TMB of 7.7 Muts/Mb. The most commonly mutated genes were TP53, TERT, CTNNB1, AXIN1, RB1, TSC2, CCND1, ARID1A, and FGF19. SNV was the most common mutation type and C:G>T:A and guanine transformation were the most common SNVs. Compared to wild-type patients, the proportion of Edmondson grade III–IV and microvascular invasion was significantly higher in TP53 mutated patients (P<0.05). The proportion of tumors invading the hepatic capsule was significantly higher in TERT mutated patients (P<0.05). The proportion of Edmondson grade I-II, alpha fetoprotein (AFP) <25 µmg/L, and those without a history of hepatitis B was significantly higher in CTNNB1 mutated patients (P<0.05). CTNNB1 mutations were associated with TMB high in HCC patients (P<0.05). Based on correlation analysis, the mutation of TP53 was independently correlated with microvascular invasion (P=0.002, OR =3.096) and Edmondson grade III–IV (P=0.008, OR =2.613). The mutation of TERT was independently correlated with tumor invasion of the liver capsule (P=0.001, OR =3.030), and the mutation of CTNNB1 was independently correlated with AFP (<25 µmg/L) (P=0.009, OR =3.414).ConclusionsThe most frequently mutated genes of HCC patients in China were TP53, TERT, and CTNNB1, which mainly lead to the occurrence and development of HCC by regulating the P53 pathway, Wnt pathway, and telomere repair pathway. There were more patients with microvascular invasion and Edmondson III–IV grade in TP53 mutated patients and more patients with hepatic capsule invasion in TERT mutated patients, while in CTNNB1 mutated patients, there were more patients with Edmondson I–II grade, AFP <25 µmg/L, and a non-hepatitis B background. Also, the TMB values were significantly higher in CTNNB1 mutated patients than in wild type patients.  相似文献   
73.
Introduction and importanceRenal cell carcinoma (RCC) accounts for 3% of all malignancies in adults, on its own being the 3rd most common urologic malignancy. Commonly RCC metastasizes to lung, bone, liver, brain but rarely to colorectum. Here we present the metastasis of RCC to colon with unusual histologic features.Case presentationA 40-year-old woman presented with abdominal pain and constipation. Colonoscopy showed an ulcerative mass 30 cm from anal verge. Subsequently, she underwent abdominoperineal resection of the involved portion of colon and the biopsy was sent to us for histopathological analysis. Grossly, it was a large fungating mass. Microscopic examination revealed a malignant neoplasm with polygonal cells, abundant eosinophilic cytoplasm, eccentric nuclei and prominent nucleoli. Immunohistochemistry confirmed the diagnosis of RCC.Clinical discussionColon rarely infiltrated by metastasis from RCC and so far, around 25 of such cases have been reported in the literature. Most common metastatic type of RCC to gastrointestinal tract is clear cell type. In our patient, the type of the metastatic RCC to colon was RCC with rhabdoid features. RCC with rhabdoid features is rare (3–5% of all RCC), but it is highly aggressive with higher chance of metastasis, extra renal invasion and poorer prognosis.ConclusionRCC should be considered as one of the differential diagnosis of colorectal cancers. Appropriate immunohistochemical workup would then reveal the correct diagnosis.  相似文献   
74.
75.
目的:分析前次妊娠期糖尿病(GDM)的临床特征对再次妊娠糖尿病复发影响。方法:回顾性收集2017年1月-2019年10月本院产科常规产前检查且前次妊娠诊断为GDM的306例产妇临床资料,根据本次妊娠GDM诊断标准分为复发性GDM组与血糖正常组,再根据葡萄糖耐量试验(OGTT)各时间点血糖水平将复发性GDM组分为复发性GDM A组(单纯FPG异常)、复发性GDM B组(FPG正常但1hPG或/和2hPG异常)、复发性GDM C组(FPG异常,同时合并1hPG或/和2hPG异常)。比较各组前次妊娠临床特点与复发关系。结果:复发性GDM组与血糖正常组年龄、产次间隔≥5年比例、前次妊娠FPG、1hPG、2hPG值及OGTT异常类型比例、前次妊娠应用胰岛素比例均有差异(P<0.05),而前次妊娠前体质指数、妊娠期增重及早产发生情况无差异(P>0.05);年龄≥35岁、前次妊娠2hPG>9.10mmol/L、1hPG或(和)2hPG异常及FPG+1hPG或(和)2hPG异常是复发性GDM的危险因素(P<0.05),而产次间隔≥5年、前次妊娠OGTT FPG>5.35mmol/L、1hPG>10.59mmol/L、前次妊娠应用胰岛素与复发性GDM无相关性(P>0.05);复发性GDM C组与A组年龄、前次妊娠OGTT 1hPG、2hPG值有差异(P<0.05),而复发性GDM C组与B组、B组与A组比较无差异(P>0.05);复发性GDM A组、B组、C组前次妊娠OGTT异常类型构成比有差异(P<0.001),产次间隔时间≥5年、前次妊娠早产、应用胰岛素比例无差异(P>0.05);年龄≥35岁及前次妊娠FPG+1hPG或(和)2hPG异常是GDM复发时血糖异常类型高等级的危险因素(P<0.05),前次妊娠OGTT 1hPG>10.59mmol/L、2hPG>9.10mmol/L、前次妊娠1hPG或(和)2hPG异常与复发性GDM孕妇OGTT异常类型无相关性(P>0.05)。结论:孕妇年龄、前次妊娠OGTT 2hPG值及异常类型可能会影响再妊娠复发性GDM的发生率及严重程度。  相似文献   
76.
Summary One hundred and six affective (76 unipolar and 30 bipolar) and 101 schizoaffective patients (45 unipolar and 56 bipolar) were investigated after a long-term course of illness, evaluating sociodemographic and general data, the long-term course of illness, disability and psychosocial alterations according to WHO/DAS, WHO/PIRS and GAS, as well as several social consequences of the illness (living situation at the end of the observation time, downward occupational drift, downward social drift, premature retirement, achievement of the expected social development). Comparing the 30 bipolar affective and 56 bipolar schizoaffective disorders, no differences were found regarding (a) sociodemographic and general data (i.e. sex distribution, age at onset, education and occupation at onset, stable heterosexual relationship, premorbid personality and social interactions, mental illness in the family, broken home, life events, season of birth and social classes) and (b) relevant patterns of the long-term course. Regarding long-term out-come the only difference found concerned the more favourable outcome of the bipolar affective disorders according to WHO/DAS, while using GAS the difference was not statistically significant. No difference was found either between the two bipolar groups in the social consequences of the illness. The combining of both bipolar groups as bipolar diseases is discussed, as well as the use of the terms bipolar disease, affective subtype and bipolar disease, schizoaffective subtype.  相似文献   
77.
作者复制了家兔病理性氧供依赖性(POSD)模型。采用渐进性低氧法降低总氧运输量(TO_2),从而考察机体氧运输及氧摄取的变化特点。结果表明,在TO_2-VO_2的关系中,对照组可清楚地分为“非依赖”与“依赖”两部分;内毒素组从呼吸空气开始,从未出现坪区,内毒素组和对照组依赖段的斜率,即氧提取率分别为0.473和0.730,两者差别显著(P<0.05)。内毒素组的动静脉血氧含量差值(CaO_2-CVO_2)在渐进性低氧过程中逐渐变小(P<0.01,ANOVA),对照组则呈相反变化趋势,故其组间差别越来越大,表明内毒素组氧提取率降低。  相似文献   
78.
A review of nine adenocarcinomas of the esophagus arising in Barrett's epithelium was undertaken. We found the disease among white males disproportionately. Risk factors and incidence rate remain to be clarified. Only one patient was in a surveillance program and only he had carcinoma discovered "early." He still survives while only one of the eight whose diagnosis followed investigation of symptoms remains alive.  相似文献   
79.
目的 探讨彩色多普勒超声鉴别诊断结节性甲状腺病变的意义。方法 回顾性分析病理或细胞学证实的结节性甲状腺病变74例二维超声和彩色多普勒超声(CDFI)表现。结果 结节性甲状腺肿、甲状腺腺瘤和腺癌超声和血流图像表现有一定规律性,定位准确,敏感性强。结论 彩色多普勒超声是诊断结节性甲状腺病变首选检查方法。  相似文献   
80.
粉防己碱对兔瘢痕组织作用的实验研究   总被引:1,自引:0,他引:1  
目的 :研究粉防己碱对兔病理性瘢痕的组织学作用 ,为瘢痕治疗提供一种新方法。方法 :采用兔耳腹侧瘢痕模型 ,用粉防己碱 5 0mg /ml、粉防己碱 10mg /ml、去炎松 40mg /ml及生理盐水分别注入瘢痕组织 ,图像分析瘢痕组织中成纤维细胞数量和胶原含量的变化。结果 :粉防己碱治疗组瘢痕组织中成纤维细胞数量与胶原含量均明显减少 ,呈剂量效应关系 ;与生理盐水对照组比较 ,有极显著差异 (P <0 .0 1) ;与去炎松对照组比较无显著差别 (P >0 .0 5 )。结论 :粉防己碱抑制瘢痕组织中成纤维细胞增殖 ,并使胶原合成减少 ,从而抑制瘢痕组织生长 ,有望成为防治病理性瘢痕的新药物  相似文献   
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