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Genetic and epigenetic alterations importantly contribute to the pathogenesis of lung cancer. In the study, we measured the frequency and distribution of molecular abnormalities of EGFR as well as the aberrant promoter methylations of BRCA1, MGMT, MLH1, and RASSF1A in Vietnamese lung adenocarcinomas. We investigated the association between genetic and epigenetic alteration, and between each abnormality with clinicopathologic parameters. Somatic EGFR mutation that was found in 49/139 (35.3%) lung adenocarcinomas showed a significant association with young age, female gender, and non-smokers. EGFR overexpression was identified in 82 tumors (59.0%) and statistical relationships with EGFR or BRCA1 methylation but not EGFR mutation. In addition, EGFR, BRCA1, MGMT, MLH1, and RASSF1A methylations were found in 33 (23.7%), 41 (29.5%), 46 (33.1%), 28 (20.1%), and 41 (29.5%) cases of a total of 139 lung adenocarcinomas, respectively. The RASSF1A methylation was found to be linked to the smoking habit. Methylations in MGMT and RASSF1A were also found to correlate with metastasis status. Furthermore, the distribution of EGFR mutation and that of BRCA1, MGMT or RASSF1A methylation were significantly exclusive in lung adenocarcinomas. The main finding of our study demonstrate that epigenetic abnormalities might play a critical role for the lung tumorigenesis in patients with smoking history and metastasis, and partly affect the predictive value of EGFR mutations through blocking expression due to promoter EGFR hypermethylation. Mutually exclusive distribution of genetic and epigenetic alterations reflects differently biological characteristics in the etiology of lung adenocarcinomas.  相似文献   
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Background: Among gastric restrictive operations, the procedure of choice is still controversial. The aim of this study is to compare the results of two different gastric restrictive procedures: vertical banded gastroplasty (VBG) and stoma adjustable silicone gastric banding (ASGB). Methods: Between 1991 and 1996, 51 patients were treated surgically for morbid obesity: 27 underwent VBG and 24 underwent ASGB. Preoperative body weight (BW), body mass index (BMI) and percentage of ideal body weight (% IBW) were (mean ± SD): 145.7 ± 45.3 kg; 53.9 ± 15.9 kg/m2; 249.1 ± 73.5% respectively in the VBG group. Corresponding figures for the ASBG group were 132.5 ± 22.7 kg; 46.9 ± 7.8 kg/m2 and 207.2 ± 35.0%. Results: In the VBG group, the median follow-up period was 26 months (range: 7-47). Eighteen months after the operation BW, BMI, % IBW and percentage of excess weight loss (% EWL) were 85.5 ± 26.8 kg, 31.9 ± 9.8 kg/m2, 145.4 ± 43.9% and 74 ± 1% respectively. Complications included incisional hernia (n = 1), and bowel obstruction (n = 1). One patient died of acute myocardial infarction on the third postoperative day. In the ASGB group, median follow-up time was 19.7 months (range: 18-26). At 18 months postoperation BW, BMI, % IBW and % EWL values were 86.6 ± 20.6 kg 30.6 ± 6.6 kg/m2 140.6 ± 29.3% and 64 ± 1% respectively. Gastric wall erosion occurred in two patients and the bands had to be removed. These patients underwent VBG 6 months later. Complications encountered in this group were incisional hernia (n = 1), outlet stenosis and reflux esophagitis (n = 1), reservoir leakage (n = 1) and gastrointestinal bleeding (n = 1). Two patients died of pulmonary embolism and acute gastrointestinal bleeding. Conclusions: Weight reduction was not statistically significant between the two groups. ASGB was easier to perform and less invasive than VBG.  相似文献   
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Bleeding into a pancreatic pseudocyst is a rare but life-threatening entity. Early diagnosis is crucial in its management. There are reports suggesting that computed tomography (CT), scintigraphy, endoscopic retrograde cholangiopancreatography (ERCP), and angiography could be the diagnostic maneuvers. In this report, we present a case of arterial bleeding into a pancreatic pseudocyst, which was diagnosed by the turbulent echo-currents seen in real-time ultrasonography.  相似文献   
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Hydatid cysts of central nervous system are rare and comprise only 2% to 3% of all hydatid cysts reported. Orbital localization is very uncommon and has been reported less than 1 % of all hydatid diseases. The primary treatment of hydatid disease is surgical. The most important complication of the surgical treatment is secondary hydatidosis due to spillage of the cyst contents. Because of the difficulties of the orbital localization, total extirpation of the cysts without rupture is almost impossible. Preventing spontaneous rupture of the cysts during surgery and postoperative antihelmintic treatment should be taken into consideration in these cases.This study includes four cases who underwent surgery for orbital hydatid cysts. Radiological characteristics, operative technique and postoperative medical therapy are discussed.  相似文献   
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采自贵州省猪尾鼠的吸虱具有特殊的形态。李氏欣奇虱独自成为一科。双叶盲鼠虱隶拟血虱科。拟血虱科中的拟血虱属和钩板虱属均寄生于鼹科,裂虱属和盲鼠虱属则寄生于睡鼠科和刺山鼠科。后者曾被置于睡鼠科。研究食虫目动物的吸虱将可能对吸虱与其宿主动物的偕同进化提供更多的证据。  相似文献   
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The aim of our study was to establish normal values of urinary pyridinoline (Pyr) and deoxypyridinoline (DPyr) excretion for children aged 3–18 years, examine the biological variability of the marker, and assess its clinical value for pediatric patients with growth hormone deficiency. Pyr and DPyr was measured in first void urine samples from 692 healthy subjects (340 boys, 352 girls) by high-performance liquid chromatography. At sampling, age, body height, and weight was recorded for all individuals. Short-term variability in crosslinks excretion was examined in four healthy children. The clinical value of the marker was studied in seven patients with growth hormone (GH) deficiency. In childhood, crosslinks excretion exceeded normal adult values by about fivefold and declined during puberty. In the age range of 13–18 years, gender-related differences in Pyr and DPyr levels were observed, presumably resulting from the earlier onset of puberty in girls. Urinary levels of Pyr and DPyr were highly correlated both in males and females. Pyr/DPyr ratio was significantly higher in adolescents than children, suggesting enhanced release of Pyr from extraosseous sources. In both genders, neither age nor anthropometric variables showed a linear effect on crosslinks excretion. The range of within-subject, short-term variability in urinary Pyr and DPyr was relatively high (CV: 6%–21%), indicating that single measurements of crosslinks excretion may not adequately reflect bone resorption rates in children. Pyr and DPyr levels were significantly lower in GH-deficient patients and normalized during human growth hormone (hGH) therapy. Significant correlations between growth velocity (GV) and crosslinks levels were found, but individual prediction of GV increment during hGH treatment may be inaccurate. Pyr/DPyr ratio was not related to GV. It is concluded that measurement of urinary Pyr and DPyr excretion in children may be a valuable tool to assess bone resorption rates in population-based studies. In individual patients, however, only qualitative evaluation of disease severity and response to treatment seems justified.  相似文献   
10.
基于"WD倒谱"法分析人体脾组织的超声散射微结构特征   总被引:1,自引:1,他引:1  
本文提出了一种对超声散射信号分析的新方法--“WD倒谱”法,并利用该方法对人体正常脾和脾增生组织的回波信号进行了分析,对软组织中散射子的平均间距进行了估计,结果表明:两种脾组织散射子的平均同距明显不同;“WD倒谱”能有效的反映软组织的微观结构特征,说明“WD倒谱”是软组织超声散射信号分析与软组织散射子平均间距定征的一种有效方法。  相似文献   
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