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221.
Jeffrey S. Duncan Martha T. Fernandez Patricia L. Abbitt Siva Thiagarajah Stuart S. Howards W. Allen Hogge M.D. 《黑龙江环境通报》1990,10(3):175-182
To delineate the natural history of fetal multicystic dysplastic kidneys (MDKs), all cases that were prenatally detected in the Prenatal Diagnosis Center of the University of Virginia from September 1985 to 31 August 1988 were reviewed. All patients were followed through the Center with serial ultrasound evaluations at approximately 4-week intervals, and each liveborn infant was evaluated and followed by one of the authors (S.S.H.) Of the 14 cases detected, ten were detected in the second trimester, the earliest at 16·5 weeks' gestation. Of the nine fetuses with non-lethal disease, there were two cases in which the lesion remained unchanged during observation. Both had an initial diagnosis in the third trimester. In those cases diagnosed in the second trimester (7), all showed an initial increase in the size and number of cysts, followed by involutional changes either in utero (2) or in the neonatal period (3). Two infants had immediate surgical removal of the MDK, one because of respiratory compromise, and the other because of an uncertain diagnosis on renal scan. Abnormalities of the contralateral kidney were found in 7 of 14 fetuses. Five were lethal conditions. Associated non-renal abnormalities were common in bilateral MDK (80 per cent), but rare in unilateral MDK (11 per cent). 相似文献
222.
固定化细胞处理废水的关键性包埋技术条件研究 总被引:9,自引:0,他引:9
研究了以聚乙烯醇为主要包埋材料的混合载体,固定化细胞处理有机废水的关键性包埋技术条件,解决了妨碍固定化细胞在废水处理领域推广应用所的制备成球难,活性丧失大、易破碎、发胀粘连上浮等问题。 相似文献
223.
《环境科学学报(英文版)》2023,35(3):735-741
Pesticides are a well-known family of chemicals that have contaminated water systems globally. Four common subfamilies of pesticides include organochlorines, organophosphates, pyrethroids, and carbamate insecticides which have been shown to adversely affect the human nervous system. Studies have shown a link between pesticide exposure and decreased viability, proliferation, migration, and differentiation of murine neural stem cells. Besides human exposure directly through water systems, additional factors such as pesticide bioaccumulation, biomagnification and potential synergism due to co-exposure to other environmental contaminants must be considered. A possible avenue to investigate the molecular mechanisms and biomolecules impacted by the various classes of pesticides includes the field of -omics. Discovery of the precise molecular mechanisms behind pesticide-mediated neurodegenerative disorders may facilitate development of targeted therapeutics. Likewise, discovery of pesticide biodegradation pathways may enable novel approaches for water system bioremediation using genetically engineered microorganisms. In this mini-review, we discuss recently established harmful impacts of various categories of pesticides on the nervous system and the application of -omics field for discovery, validation, and mitigation of pesticide neurotoxicity. 相似文献
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Prenatal diagnosis of methylenetetrahydrofolate reductase (MTHFR) deficiency and family studies were performed because of a severely affected first child in this family. The fetus at risk was found to be heterozygous as confirmed by the enzymatic activity assay performed several times after birth. In the father, MTHFR activity was normal in lymphocytes and decreased in fibroblasts, whereas in the asymptomatic mother, the activity was not detectable in fibroblasts and was very low in lymphocytes. The absence of any clinical symptoms in the mother despite a clear MTHFR deficiency and hyperhomocystinemia emphasizes the heterogeneity of this disease. 相似文献
226.
Cultured amniotic fluid cells from four anencephalic pregnancies were characterized in indirect immunofluorescence (IIF) microscopy using specific antibodies against different types of cytoskeletal intermediate filaments. Most of the cells showed a fine fibrillar cytoplasmic fluorescence with antibodies against glial fibrillary acidic protein (GFA), indicating that amniotic fluid cells in anencephalic pregnancies are of glial origin. The GFA-positive cells were rapidly adhering and proliferating. They remained as the major cell type also in long term cultures, and could easily be recovered from liquid nitrogen without losing their GFA positivity. GFA-positive cells were pleomorphic in appearance, and occurred in several morphologically different shapes. Amniotic fluid from one of the anencephalic cases contained typical neuronal cells, which in IIF were GFA-negative but could specifically be stained with anti-neurofilament antibodies. Most of the GFA-negative cells in all the cases were fibroblasts, identified by their fluorescence only with antibodies against vimentin. Epithelial cells showing positive keratin-fluorescence in IIF, were seen only occasionally. 相似文献
227.
Prenatal diagnosis of a heterozygote for mucopolysaccharidosis type VII (β-glucuronidase deficiency)
We had the opportunity of investigating a case (BK) of a severe form of mucopolysacchari- dosis with nearly total deficiency of β-glucuronidase in serum, leucocytes and fibroblasts. We here report results obtained by prenatal diagnosis of a clinically normal child (BK's sister), and point out the difficulty in interpreting a heterozygous level of β-glucuronidase activity in cultured amniotic cells. Four successive passages of amniotic cells were tested for β-glucuronidase and α-mannosidase activity in at-risk and control cells. In different passages, enzyme activity was between 8 and 49 per cent of controls but 2 to 18 times higher than fibroblasts from the affected brother (BK). The highest activity was observed in the first passage and the lowest in the third. The electrophoretic separation of GAGS from at-risk amniotic fluid showed a normal pattern. We discuss the correlation between enzyme levels in different passages of cultured cells and that found in leucocytes and fibroblasts from the propositus and parents. From a practical point of view, we conclude that the first passage gives the most reliable results for prenatal diagnosis. 相似文献
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