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排序方式: 共有256条查询结果,搜索用时 14 毫秒
51.
Ulrich Harréus MD PhD Philipp Baumeister Norbert Kleinsasser Maximilian Reiter Beatrice Bachmeier Christoph Matthias 《毒物与环境化学》2013,95(2):205-214
The etiology of salivary gland malignancies still remains unclear. Metal compounds are of special interest since they show ubiquitous presence in the environment, are present in many working places, and are accepted (co-)carcinogens in some other malignancies. Metals enter the body as xenobiotics by inhalation or ingestion. This study investigated the genotoxic potential of sodium dichromate (Na2Cr2O7), nickel sulfate (NiSO4), cadmium sulfate (CdSO4) and zinc chloride (ZnCl2) on human salivary gland cells and lymphocytes. Macroscopically healthy tissue of salivary glands was harvested from 46 patients during surgery and isolated to single cells by enzymatic digestion. The cells were incubated with Na2Cr2O7, NiSO4, CdSO4 or ZnCl2. Na2Cr2O7 was also incubated in combination with the other metal compounds listed. Carcinogenic and co-carcinogenic effects of cadmium were tested by incubation with Na2Cr2O7 and consecutive repair intervals. DNA damage and repair were evaluated by the Comet assay, determining DNA-strand breaks. The extent of damage was quantified using a digital analysis system. Na2Cr2O7 produced significantly enhanced DNA-strand breaks in human salivary gland tissue and lymphocytes. All other metal compounds exerted no damaging effect on both cell types. Co-incubation of Na2Cr2O7 with the other metals revealed a significant additive effect only for CdSO4. Specific analysis of the influence of cadmium showed a reduction of DNA-repair after Na2Cr2O7-induced strand breaks in salivary gland cells. This study provides evidence that exposure to distinct metals may significantly contribute to malignant salivary gland tumors. In consequence, further studies as epidemiological and toxicological data are warranted to determine the role of distinct metals as potential (co-) carcinogens. 相似文献
52.
A case of retinoic acid embryopathy which was retrospectively diagnosed after delivery is presented. The affected fetus was exposed to the drug during the first month of pregnancy and second-trimester sonographic examination showed hydrocephalus and cardiacmalformation. The diagnosis was made on the basis of autopsy findings and genetic enquiry. 相似文献
53.
Prenatal paternity testing was evaluated by DNA analysis in chorionic villus biopsies obtained during the 7th-22nd weeks of gestation. Using highly polymorphic variable number of tandem repeats (VNTR) probes, we analysed four cases consisting of mother/child/alleged father trios. In all cases, we were able to detect maternal and paternal alleles and could establish or exclude paternity. The application of DNA analysis represents a new important diagnostic aid for all cases that require a prenatal identification of paternity. 相似文献
54.
Jon Barret Dr David Chitayat MD FABMG FCCMG Matthew Sermer Koffi Amankwah Robert Morrow Ants Toi Greg Ryan 《黑龙江环境通报》1995,15(9):849-853
The prenatal diagnosis of an echogenic fetal lung (EFL) is now often made in the early second trimester using high-resolution ultrasound. This ultrasound appearance is usually caused by a congenital cystic adenomatoid lung malformation (CCAM), an intrapulmonary lung sequestration or obstruction of a major airway. In order to provide prognostic guidelines to parents who may be considering termination of a fetus with these findings, we have analysed a series of 11 cases diagnosed in our centre over the past 2 years in conjunction with 60 cases from major published series. The data suggest that in the absence of non-immune hydrops fetalis (NIHF) or other anomalies, the outcome for the fetuses is excellent, with over 90 per cent survival. Neither early diagnosis (24 weeks) nor the presence of mediastinal shift is a poor prognostic indicator. In addition, it appears that if NIHF is absent at diagnosis, the chance that it will develop as the pregnancy continues is small (6 per cent). Furthermore, there is a significant (up to 30 per cent) chance that this ultrasound finding will resolve in utero. The development of in utero fetal surgical techniques may be the only hope for those hydropic fetuses who appear to have a dismal prognosis. 相似文献
55.
Magnetic resonance (MR) imaging was performed at 29 weeks of pregnancy after ultrasonographic detection of an abnormal cleft in the fetal brain. Fetal neuromuscular blockade was induced by pancuronium bromide injected into the umbilical vein under continuous ultrasound (US) guidance. MR images supported the echotomographic diagnosis of schizencephaly improving the visualization of symmetrical broad clefts connecting the lateral ventricles with the subarachnoid space. Schizencephaly was finally confirmed by neonatal US, computed tomography, and MR. 相似文献
56.
J. M. M. van Lith MD J. R. Beekhuis A. J. van Loon A. Mantingh B. T. H. M. de Wolf A. S. P. M. Breed 《黑龙江环境通报》1991,11(8):625-628
In order to gain more insight into the association between alpha-fetoprotein (AFP) and fetal chromosomal disorders, especially Down's syndrome, we measured AFP in fetal serum, amniotic fluid, and maternal serum at cordocentesis. We compared the concentration and gradient of AFP in these three compartments. Our data confirm earlier findings on second-trimester fetal serum AFP concentration. The results indicate that low maternal serum AFP in pregnancies with fetal chromosomal disorders could result from an impaired fetal kidney function as well as from impaired membrane or placental passage of AFP, rather than from reduced fetal AFP production. 相似文献
57.
58.
M. M. Van Zalen-Sprock MD J. M. G. Van Vugt J. J. Van Der Harten H. P. Van Geijn 《黑龙江环境通报》1995,15(2):171-177
Two cases of sirenomelia are described, detected in the 14th and 16th weeks of gestation by transvaginal ultrasonography. A hypothesis for the aetiology of sirenomelia and its associated anomalies is discussed. 相似文献
59.
Four fetuses with a femur measuring greater than two standard deviations below the mean compared with the biparietal diameter are presented. These four fetuses were subsequently determined to have severe intrauterine growth retardation and no evidence of skeletal dysplasias. 相似文献
60.
David M. Sherer MD Jacques S. Abramowicz Richard Jaffe James R. Woods Jr 《黑龙江环境通报》1993,13(10):953-956
We present a case of a twin with trisomy 47,XX+i(9p) in whom the diagnosis of cleft palate was confirmed by colour Doppler imaging demonstrating abnormal fluid flow across the fetal pharyngeal bone defect. Application of this technique in cases predisposed for this congenital lesion may prove beneficial in the diagnosis of the more subtle types of isolated cleft palate. 相似文献