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21.
目的 探讨Lugol液染色对食管早期癌和癌前病变的诊断价值。方法 对45例食管黏膜可疑病变经内镜以2%Lugol液喷洒染色,观察黏膜染色情况,并取活检送病理组织学检查。结果 45例食管病变染色后,39例呈浅染色或不染色,其中食管癌8例(食管早期癌5例,进展期癌3例),Barrett食管5例,轻至中度不典型增生1l例。本组Lugol液染色对食管早期癌和癌前病变的检出率达46.7%。结论 内镜下应用Lugol液染色结合活检有助于食管早期癌和癌前病变的诊断,且操作简便,具有重要的临床价值。  相似文献   
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目的探讨Survivin在食管癌组织中的表达及其与bcl-2蛋白表达的相关性。方法应用免疫组织化学SP法,检测Survivin、bcl-2蛋白在68例食管癌组织和20例正常食管组织中的表达。结果Survivin蛋白在正常食管组织中低表达或不表达,68例食管癌组织中,49例表达阳性,占72.1%。Survivin蛋白表达与分化程度、淋巴结转移密切相关(P<0.05)。食管癌组织bcl-2蛋白表达阳性、阴性组中,Survivin蛋白阳性表达率分别为94.7%(36/38)和43.3%(13/30),两者比较,差异有统计学意义(P<0.05)。Survivin蛋白表达与bcl-2蛋白表达密切相关。结论Survivin在食管癌组织中表达上调,通过抑制细胞凋亡,在食管癌的发生中起到重要作用;凋亡相关基因bcl-2的上调与Survivin的表达可能在食管癌变中起协同作用。  相似文献   
24.
PTEN及Bcl-2蛋白在膀胱移行细胞癌中的表达及其意义   总被引:1,自引:0,他引:1  
乔宝民  孙光  畅继武  韩瑞发  王文成  马腾骧 《天津医药》2006,34(12):844-845,I0004
目的:探讨PTEN及Bcl-2蛋白在膀胱移行细胞癌的表达规律及其临床意义。方法:应用免疫组织化学链亲和素-生物素-霉复合物(SP)方法检测43例膀胱移行细胞癌和7例正常黏膜组织中PTEN及Bcl-2蛋白的表达.分析二者的表达与膀胱癌病理参数的关系。结果:(1)G1、G2、G3肿瘤PTEN表达阳性率分别为85.7%、80.4%、73.3%,浸润性肿瘤和表浅性肿瘤表达阳性率分别为70.4%和93.8%,说明PTEN表达阳性率与肿瘤病理分级、临床分期有关。(2)G。、G2、G3肿瘤Bcl-2表达阳性率分别为14.2%、57.14%、66.67%,浸润性肿瘤和表浅性肿瘤表达阳性率分别为59.3%和43.8%,说明Bcl-2表达阳性率与肿瘤病理分级、临床分期有关。(3)随着肿瘤恶性程度的增高和临床分期进展,PTEN蛋白阳性率呈下降,Bcl-2表达呈增高趋势,二者表达呈负相关关系。结论:PTEN的抑癌作用可能与Bcl-2有关.二者的异常表达在膀胱移行细胞癌的发生、发展过程中起重要作用。二者同时检测有助于判断预后。  相似文献   
25.
Obstructive sleep apnea syndrome (OSAS) is a common condition characterized by repetitive sleep‐induced collapse of the upper airways. It is associated with increased risk for hypertension, ischemic heart disease, cerebral stroke, and traffic accidents. In contrast, gastroesophageal reflux disease (GERD) is a very common disorder defined as various symptoms or esophageal mucosal damage generated by the abnormal reflux of gastric contents into the esophagus. Patients with OSAS have been reported to have a high prevalence of gastroesophageal reflux (GER) symptoms. The increase of transdiaphragmatic pressure in parallel with the large negative intrathoracic pressure produced during apnea events may directly lead to GER. In addition, some studies have demonstrated improvement in GERD with the application of continuous positive airway pressure, most consistently effective treatment for OSAS. However, GER dose not occur with every apnea. Moreover, the common conditions observed in patients with OSAS, including obesity or alcohol ingestion, are also predisposing factors for GER. A more recent investigation in over 1000 subjects failed to show a causal link between both diseases. Thus, the potential relationship between OSAS and GERD remains controversial. Inconsistencies in definitions of both diseases or sampling biases may contribute to the confusing results.  相似文献   
26.
The antiproliferative, cytotoxic and apoptogenic activities of Bufo melanostictus (Indian common toad) skin extract (TSE) on U937 and K562 leukemic cell line has been investigated. TSE significantly (P<0.001) reduced the time-dependent cell proliferation and decreased MTT values in U937 and K562 cells. TSE (IC50 doses) suppressed the proliferating cell nuclear antigen expression in both the cells. It was demonstrated that, TSE (IC50 doses) primarily arrested the U937 and K562 cells at G1 phase of the cell cycle. Confocal microscopy showed the altered fragmented nuclei and apoptotic bodies formation in TSE (IC50 doses) treated U937 and K562 cells. Membrane blebbing, cell surface shrinkage and perforation were observed through scanning electron microscope. TSE-induced DNA fragmentation in U937 and K562 cells was reflected in single-cell gel electrophoresis. TSE significantly (P<0.001) increase the length-width ratio of DNA mass as compared to control in comet assay. The flow cytometric analysis of annexin-V binding to the cancer cells further supported the apoptotogenic activity of TSE. The effect of TSE on normal human peripheral blood mononuclear cells viability and cytotoxicity was studied in culture and found to be less cytotoxic than on the U937 and K562 cells. The findings from the present study suggested that TSE might possess potent antineoplastic agent having antiproliferative, cytotoxic and apoptogenic activity against U937 and K562 myeloid leukemic cells.  相似文献   
27.
AIM: The clinical significance of the urinary white blood cell (U-WBC) count and serum C-reactive protein (CRP) level was evaluated in an effort to improve the efficiency of prostate biopsies. METHODS: We enrolled 228 consecutive patients with serum prostate-specific antigen (PSA) ranging from 3.0 to 20.0 ng/mL, normal digital rectal examination findings, and who underwent prostate biopsies between January 2001 and August 2004. Of these, 157 patients had histologically confirmed benign prostatic disease and the remaining 71 patients had prostate cancer. Patients with a pretreatment U-WBC count < or =3 or >3/high power field were defined as non-pyuria and pyuria, respectively. The patients were also separated into two groups based on the serum CRP level prior to biopsy. Several clinical factors were compared among these subgroups. RESULTS: Inflammation was histologically detected at rates of 58.1% and 34.1% in the pyuria and non-pyuria groups, respectively (P = 0.0014). The rates of cancer detection were significantly lower in the pyuria, than in the non-pyuria group (P = 0.0384). The cancer detection rates did not significantly differ according to serum CRP levels prior to biopsy. CONCLUSION: The U-WBC count appears to be a reliable indicator of minute prostatic inflammation. The serum PSA level was elevated in patients with asymptomatic prostatitis. Counting U-WBC is a simple, convenient and non-invasive method that should be valuable part of routine urological examinations.  相似文献   
28.
In a retrospective study using univariate analysis, we identified tumor type (nonendometrioid vs endometrioid), depth of myoinvasion (MI), mode of MI (infiltrative vs cohesive), and direct anatomic invasion of the cervical wall from the isthmus as significant positive risk factors for intramyometrial lymphvascular space involvement (LVSI). On multivariate analysis, tumor grade, depth of MI, and mode of MI retained their significance. We created a grid for the relative risks of LVSI with respect to these variables individually or in combination. We suggest that our indirect estimate of the risk of LVSI can help in assessing prognosis and determining the need for adjuvant therapy whenever LVSI is important in clinical decision making, but its pathologic diagnosis is uncertain.  相似文献   
29.
BACKGROUND: 1Alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2) Vitamin D(3)] induces growth inhibition in squamous cell carcinoma (SCC) cell lines of the head and neck by arresting the cells in the G0/G1 phase of the cell cycle, probably due to an enhanced expression of p21, which could be demonstrated in other cell lines (JPPA, SCC9) before. In SCC25, a SCC cell line isolated from tongue, growth inhibition but no overexpression of p21 was detected. The retinoblastoma gene, as a direct target of G1 cyclin-CDK complexes, showed an obvious shift from the hyperphosphorylated to the hypophosphorylated form under 1,25(OH)(2)Vitamin D(3), which indicates that the growth inhibition takes place in the G0/G1 phase. To explore the possible pathway of growth inhibition in SCC25 we investigated other cell cycle inhibitors (p18, p19, p27). METHODS: Synchronized cells were treated with 1,25(OH)(2)Vitamin D(3) over 96 h. The cell cycle status and expression of cell cycle-regulating proteins was determined by fluorescence-activated cell sorting (FACS) and Western blotting. An overexpression of p18 in 1,25(OH)(2)Vitamin D(3) vs. ethanol-treated cells was determined until 30 h in SCC25. No influence was detectable on the expression of p27 and p19. CONCLUSION: One mechanism by which 1,25(OH)(2)Vitamin D(3) controls cell growth might be the upregulation of p21. As p21 was unsusceptible to 1,25(OH)(2)Vitamin D(3) in SCC25, other inhibiting proteins were necessary to be tested. The proven upregulation of p18 seems to be the responsible step for growth inhibition of 1,25(OH)(2)Vitamin D(3) in SCC25.  相似文献   
30.
Background and Aim: This study investigated the clinical features of hepatocellular carcinoma in patients with sustained virological response to interferon for hepatitis C viral (HCV) infection. Methods: A total of 7715 patients with HCV infection were treated with interferon and followed up for more than 1 year after withdrawal of interferon in 64 Japanese hospitals and clinics between July 1988 and August 2001. Sustained virological response was obtained in 2515 (32.6%) patients. Of these 2515 patients, clinical data were collected for 38 patients in whom hepatocellular carcinoma developed. Sustained virological response was defined as HCV RNA negativity more than 6 months after the termination of interferon. Results: All patients were HCV RNA negative at the time of diagnosis of hepatocellular carcinoma. The median period until the detection of hepatocellular carcinoma was 4.7 years (range 1.4–9.0 years). There were significant improvements in hepatic function including serum albumin, aspartate aminotransferase, alanine aminotransferase, indocyanine green test, platelet count and histological activity grade in comparison with those before interferon therapy and at the onset of hepatocellular carcinoma. The maximum tumor size in patients without medical follow‐up for 1 year or more (median: 60 mm) was significantly larger than in patients who were periodically followed up for 6 months or less (median: 25 mm) (P = 0.002). Conclusions: The present findings emphasize the importance of regular medical follow up of patients with HCV infection, as even patients showing a sustained virological response to interferon and in whom hepatic function has improved have the potential to develop hepatocellular carcinoma.  相似文献   
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