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排序方式: 共有579条查询结果,搜索用时 15 毫秒
51.
P53 mutations in hepatocellular carcinoma patients in Egypt 总被引:3,自引:0,他引:3
El-Kafrawy SA Abdel-Hamid M El-Daly M Nada O Ismail A Ezzat S Abdel-Latif S Abdel-Hamid A Shields PG Loffredo C 《International journal of hygiene and environmental health》2005,208(4):263-270
The p53 gene plays a major role in hepatocellular carcinoma (HCC). Acquired mutations may provide clues to etiology, as some carcinogenic agents are associated with specific genetic changes in p53. Our aim was to analyze the spectrum of p53 mutations in tumor tissues from subjects with HCC in Egypt, where there is a rising incidence of HCC due to hepatitis C virus (HCV). We collected tumor tissues from 41 subjects with HCC diagnosed at the National Cancer Institute of Cairo University during 2000-2003. Sequence mutations were analyzed by the Affymetrix GeneChip technique. HCV RNA was detected in the sera of 37 subjects (90%). Only one patient had a current HBV infection. A total of 17 of the 41 subjects (41%) had p53 mutations. Thirteen of these were in exon 7, of which 10 were in codon 249, but only 8 of the 10 were the R249S mutation, previously reported to be associated with aflatoxin exposure. The other three exon 7 mutations were found in codons 232, 242 and 248. A total of three mutations were detected in exon 5 codons 133, 144 and 176. One mutation was detected in exon 8 codon 275. Unlike previous studies, this population is characterized by a high prevalence of chronic HCV infection. The presence of the R249S mutation in exon 7 may indicate that these subjects with HCC have been exposed to aflatoxin (AFB1), and further investigation is in progress to measure AFB1-albumin adducts in the sera of these subjects. 相似文献
52.
Computed tomography of the infratemporal fossa 总被引:2,自引:0,他引:2
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Violi F Loffredo L Marcoccia A 《Current drug targets. Cardiovascular & haematological disorders》2004,4(3):289-294
Peripheral arterial disease (PAD) is an important manifestation of systemic atherosclerosis that is characterized by obstruction of the arteries in the lower limbs. Experimental and epidemiological studies suggest a key role for oxidative stress in initiation and progression of the atherosclerotic process. The results of these studies provided a good basis for interventional trials with antioxidants, particularly with vitamin E, but the findings were conflicting. In this paper we review the observational and interventional studies with antioxidants, and ask whether vitamin supplementation should be recommended for PAD patients. 相似文献
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Toriello-Carey syndrome is a rare malformative complex, described for the first time in 1988, characterized by agenesis of the corpus callosum, facial anomalies, cardiac defects and hypotonia. Relatively few neonatal cases have been reported. We describe here the first prenatal ultrasound diagnosis of the syndrome based on the detection of agenesis of the corpus callosum and spongious cardiomyopathy in a 22-week-old fetus of a couple with positive family history. The first sib of the couple was diagnosed with Toriello-Carey syndrome at 1 year of age, and had, in addition to the typical facial anomalies not detectable by ultrasound, agenesis of the corpus callosum and the same heart lesion (spongious cardiomyopathy). This report demonstrates that prenatal diagnosis of Toriello-Carey syndrome is feasible in the second trimester of pregnancy. 相似文献
58.
PURPOSE: Whether pretreatment factors that predict for time to prostate specific antigen (PSA) failure also predict for time to prostate cancer specific death after PSA failure for patients with competing causes of mortality treated during the PSA era was the subject of this study. MATERIALS AND METHODS: Of 415 men with a median age of 73 years who underwent external beam radiation therapy between 1988 and 2001 for clinically localized prostate cancer 160 (39%) experienced PSA failure and 96 (23%) died. In 46 men (48%) the cause of death was prostate cancer. Cox regression multivariable analyses (multivariable analysis) were performed to evaluate the ability of the pretreatment PSA and centrally reviewed biopsy Gleason score to predict time to prostate cancer specific death after PSA failure. RESULTS: When analyzed as categorical variables using multivariable analysis, biopsy Gleason score 4 + 3 (p = 0.02), 8 to 10 (p = 0.02) disease and a pretreatment PSA greater than 20 ng./ml. (p = 0.03) were significant predictors of time to prostate cancer specific death after PSA failure. Estimates of prostate cancer specific death 5 years after PSA failure were 24%, 40% and 59% (p = 0.01) for patients with a biopsy Gleason score < or = 6, 3 + 4, 4 + 3 or higher and 22%, 40% and 60% (p = 0.04) for patients with a pretreatment PSA of 10 or less, greater than 10 and 20 or less, or greater than 20 ng./ml., respectively. CONCLUSIONS: Patients at high risk for PSA failure after radiation therapy based on pretreatment PSA greater than 20 ng./ml. or biopsy Gleason score 4 + 3 or greater are also at high risk for death from prostate cancer after PSA failure despite competing causes of mortality. 相似文献
59.
Vitamin A and cardiac outflow tract defects 总被引:3,自引:0,他引:3
Botto LD Loffredo C Scanlon KS Ferencz C Khoury MJ David Wilson P Correa A 《Epidemiology (Cambridge, Mass.)》2001,12(5):491-496
To assess the relationship between maternal intake of vitamin A and cardiac outflow tract defects, we examined data from a population-based case-control study among liveborn infants born from 1987 through 1989 to mothers residing in the Baltimore-Washington area. Case infants (126) had a nonsyndromic cardiac outflow tract defect. Control infants (679) did not have birth defects and were a stratified random sample of liveborn infants from the same area. The main exposure was average daily maternal intake of retinol and provitamin A carotenoids from foods and supplements during the year before conception. Compared with an average intake of less than 10,000 IU, retinol intake of 10,000 IU or more from supplements was associated with a ninefold increased risk for transposition of the great arteries (odds ratio = 9.2; 95% confidence interval = 4.0-21.2), but not for outflow tract defects with normally related arteries (odds ratio = 0.8; 95% confidence interval = 0.1-6.6). Similar intakes of carotenoids and dietary retinol were not associated with an increased risk for either type of outflow tract defect. 相似文献
60.
Batori M Lazzaro M Lonardo MT Lupi M Annessi M Loffredo L Mugnaini L Sportelli G 《European review for medical and pharmacological sciences》1999,3(4):155-157
The authors report a rare case of a pulmonary neurofibroma treated by surgical excision. The case report is accompanied by a review of the literature and the discussion of the diagnostic problems posed by neurogenic tumors of the thorax. 相似文献