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71.
72.
T E Buffart R M Overmeer R D M Steenbergen M Tijssen N C T van Grieken P J F Snijders H I Grabsch C J H van de Velde B Carvalho G A Meijer 《British journal of cancer》2008,99(11):1802-1807
T-lymphocyte maturation associated protein, MAL, has been described as a tumour-suppressor gene with diagnostic value in colorectal and oesophageal cancers, and can be inactivated by promoter hypermethylation. The aim of this study was to analyse the prevalence of MAL promoter hypermethylation and the association with mRNA expression in gastric cancers and to correlate methylation status to clinicopathological data. Bisulphite-treated DNA isolated from formalin-fixed and paraffin-embedded samples of 202 gastric adenocarcinomas and 22 normal gastric mucosae was subjected to real-time methylation-specific PCR (Q-MSP). Two regions within the MAL promoter (M1 and M2) were analysed. In addition, 17 frozen gastric carcinomas and two gastric cancer cell lines were analysed both by Q-MSP and real-time RT–PCR. Methylation of M1 and M2 occurred in 71 and 80% of the gastric cancers, respectively, but not in normal gastric mucosa tissue. Hypermethylation of M2, but not M1, correlated with significantly better disease-free survival in a univariate (P=0.03) and multivariate analysis (P=0.03) and with downregulation of expression (P=0.01). These results indicate that MAL has a putative tumour-suppressor gene function in gastric cancer, and detection of promoter hypermethylation may be useful as a prognostic marker. 相似文献
73.
74.
J G Thorpe-Beeston K H Nicolaides R J Snijders C V Felton S Vyas S Campbell 《British journal of obstetrics and gynaecology》1991,98(11):1163-1167
OBJECTIVE--To study the relation between changes in the fetal thyroid hormone and thyroid stimulating hormone (TSH) concentrations and alterations in the fetal circulation as assessed by Doppler ultrasound. DESIGN--A cross-sectional study of small for gestational age (SGA) and red-cell isoimmunized fetuses undergoing cordocentesis and Doppler studies for the assessment and determination of fetal karyotype, acid-base balance and haemoglobin concentration. SETTING--Harris Birthright Research Centre for Fetal Medicine, King's College, London. SUBJECTS--38 growth retarded and 38 red-cell isoimmunised fetuses. INTERVENTIONS--Cordocentesis. MAIN OUTCOME MEASURES--Serum TSH total and free thyroxine (T4, FT4) and total and free triiodothyronine (T3, FT3) concentrations; middle cerebral artery (MCAVm) and descending thoracic aorta (AoVm) mean blood velocities; fetal Po2 and haemoglobin concentration (Hb). RESULTS--Delta values (delta) calculated as the number of SDs from the respective normal mean for gestation were used to compare the results with those from a previous study of normal fetuses. Mean AoVm was increased in the isoimmunized fetuses (P less than 0.001) but decreased in the SGA fetuses (P less than 0.001). Mean MCAVm was increased in both groups (P less than 0.01; P less than 0.001). There were significant associations between the gestational age adjusted values for TSH and MCAVm (r = 0.23, P less than 0.05) and between T4, FT4 or FT3 and AoVm (r = 0.41, P less than 0.01; r = 0.50, P less than 0.01; r = 0.36, P less than 0.01 respectively). In addition, T4 and FT4 were associated with delta Po2 and delta Hb. CONCLUSION--In the hypoxaemic hypoxia of growth retardation and the anaemic hypoxia of rhesus disease there are significant associations between changes in fetal thyroid hormone concentrations and changes in fetal blood flow as assessed by Doppler. Irrespective of whether altered blood flow is the cause or effect of changes in thyroid hormone concentrations, the observed changes could have beneficial effects for fetal survival, in the presence of a hostile intrauterine environment. 相似文献
75.
Twin-twin transfusion syndrome during the 2nd trimester is associated with small intertwin hemoglobin differences. 总被引:2,自引:0,他引:2
In four twin pregnancies presenting with acute 2nd-trimester polyhydramnios due to presumed twin-twin transfusion syndrome, the fetal hemoglobin concentration was measured in samples obtained by cordocentesis. In no instance did the twin pair difference in the hemoglobin concentration exceed 2.7 g/dl. 相似文献
76.
N J Saunders R J Snijders K H Nicolaides 《American journal of obstetrics and gynecology》1992,166(3):820-824
Amniocentesis and drainage were performed in 19 twin pregnancies initially seen at less than 28 weeks' gestation with acute polyhydramnios caused by the twin-twin transfusion syndrome. The procedure was performed an average of three times for each patient (range one to six), with the removal of a mean volume of amniotic fluid of 2600 ml on each occasion (range 500 to 6700 ml). The interval between initial examination and delivery averaged 7 weeks (range 1 day to 18 weeks); 14 (37%) of the 38 babies survived the neonatal period. In the pregnancies with poor outcomes, the intertwin disparity in fetal size and the mean volume of amniotic fluid drained at each amniocentesis were greater than in the pregnancies in which one or both twins survived. 相似文献
77.
During an 8-year period, oedema in the dorsal cervical region that produces a characteristic tremor on ballotement of the fetal head (nuchal oedema) was observed in 145 (7%) of the 2,086 fetuses that underwent karyotyping in our unit because of fetal malformations and/or growth retardation. Nuchal oedema was distinguished from nuchal cystic hygromata and from hydrops foetalis. In 132 (91%) of the cases with nuchal oedema, there were other fetal malformations, and 53 (37%) fetuses had chromosomal abnormalities, mainly trisomy 21 but also other trisomies, deletions or translocations, triploidy and Turner syndrome. Furthermore, the chromosomally normal fetuses with nuchal oedema had a very poor prognosis because, in many cases, there was an underlying skeletal dysplasia, a genetic syndrome or cardiac defect. 相似文献
78.
After the introduction of the colposcope for the examination of children suspected of being sexually abused in Leeds, a study was undertaken to describe the findings in detail. A total of 109 consecutive prepubertal girls, mean age 70.4 months were assessed including colposcopic genital and anal examination, and peer group review of reports and photographs. Fifty nine children had signs consistent with blunt force penetrating trauma (hymenal transection/major notch, scar, or hymenal attenuation). Transections were encountered most commonly at 6 o'clock (directly posterior). In 46 the hymenal orifice was gaping with thigh abduction only and in 47 the hymenal orifice transverse diameter was greater than 4 mm on labial separation. Overall, physical findings were commonly present and in only two cases were no signs recorded. Non-specific and frequent findings included patterns of labial and introital reddening. Supportive hymenal signs including swelling, rounding of edge, thickening, distortion, and loss of symmetry were common. Labial fusion was present in 20. Urethral dilatation with labial separation was noted in 14. Physical findings including normality are consistent with abuse and even minor anogenital signs as well as negative findings should be documented. Colposcopy and photography are valuable tools in peer review, teaching, and case management. 相似文献
79.
80.
Human papillomavirus 16 load in normal and abnormal cervical scrapes: an indicator of CIN II/III and viral clearance 总被引:12,自引:0,他引:12
van Duin M Snijders PJ Schrijnemakers HF Voorhorst FJ Rozendaal L Nobbenhuis MA van den Brule AJ Verheijen RH Helmerhorst TJ Meijer CJ 《International journal of cancer. Journal international du cancer》2002,98(4):590-595
The relation between human papillomavirus type 16 (HPV 16) viral load in cervical scrapes and development of high-grade cervical intraepithelial neoplasia (CIN II or III) was studied in a nested case-control study of women with normal cytology (group A) and in a cohort of women with abnormal cytology (group B). HPV 16 DNA load was determined using a quantitative real-time PCR assay. In group A, case women (women with CIN II/III, n = 12) had a significantly higher viral load than control women (women with CIN < or = I, n = 47). This resulted in an increased relative risk of women with the 50% highest viral load for development of CIN II/III (OR 7.7; CI 1.6-33). In group B, women with CIN II/III (n = 38) had a significantly higher viral load than women with CIN < or = I (n = 25). Women with the 50% highest viral load had an increased relative risk of CIN II/III (OR 3.2; CI 1.1-9.3) and a decreased chance of both viral clearance and cytologic regression. Our data suggest that in women with normal cytology an increased HPV 16 load confers an increased risk of developing a CIN lesion. A sustained high viral load is subsequently informative for progression to a high-grade CIN lesion. 相似文献