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Uniparental isodisomy (iUPD) is a rare genetic condition caused by non-disjunction during meiosis that ultimately leads to a duplication of either the maternal or paternal chromosome in the affected individual. Two types of disorders can result, those due to imprinted genes and those due to homozygosity of recessive disease-causing mutations. Here, we describe the third known case of complete chromosome 4 iUPD of maternal origin. This condition became apparent during whole genome linkage studies of psychiatric disorders in the Portuguese population. The proband is an adult female with normal fertility and no major medical complaints, but a history of major depressive disorder and multiple suicide attempts. The proband's siblings and parents had normal chromosome 4 genotypes and no history of mood disturbance. A brief review of other studies lends support for the possibility that genes on chromosome 4 might confer risk for mood disorders. We conclude that chromosome 4 maternal uniparental disomy (UPD) is a rare disorder that may present with a major depressive phenotype. The lack of a common disease phenotype between this and two other cases of chromosome 4 iUPD [Lindenbaum et al. [1991] Am J Med Genet 49(Suppl 285):1582; Spena et al. [2004] Eur J Hum Genet 12:891-898) would suggest that there is no vital maternal gene imprinting on chromosome 4. However, since there is no reported case of paternal chromosome 4 UPD, paternal gene imprinting on chromosome 4 cannot be excluded.  相似文献   
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From 1970 to 1980, 153 patients with stages A2, B1 and B2 prostatic cancer and proved negative pelvic lymph nodes underwent radical prostatectomy (84 underwent radical perineal and 69 underwent radical retropubic prostatectomy). Seventeen patients were lost to followup. Of 136 patients who were followed for 5 years or until death 128 (94 per cent) were alive at 5 years, including 118 (87 per cent) who were without evidence of recurrence. Patients with microscopic invasion of the prostatic capsule have a better outcome at 5 years than those with microscopic involvement of the seminal vesicles. Only 46 of the patients could be assessed at 10 years or had died 6 to 10 years postoperatively. Results at 10 years are considered preliminary, since many more patients will reach the 10-year milestone within the next few years.  相似文献   
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The oxygen-sensitive bioreductive binding of 2-nitroimidazoles labeled with fluorescent side chains has been used to stain hypoxic mammalian cells selectively. Several novel compounds were synthesized with a 1-substituent containing a fluorescent, bicyclic system having a bridgehead-nitrogen atom. Additional amine and secondary alcohol substituents were also included in the link between the fluorophor and the nitroimidazole to improve water solubility. Their ability to discriminate between hypoxic and oxic cells was compared by flow cytometric analysis. A wide range of cellular fluorescence and hypoxic-oxic differentials in fluorescence was observed when compounds with indolizine fluorophors were incubated with cells, and one such compound was considered suitable for further evaluation in vivo. Two compounds with bimane fluorophors gave very little cellular fluorescence when incubated with hypoxic cells.  相似文献   
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We investigated the antiproliferative effect of two polyhydroxylated (quercetin and taxifolin) and two polymethoxylated (nobiletin and tangeretin) flavonoids against three cell lines in tissue culture. Tangeretin and nobiletin markedly inhibited the proliferation of a squamous cell carcinoma (HTB 43) and a gliosarcoma (9L) cell line at 2-8 micrograms/ml concentrations. Quercetin displayed no effect on 9L cell growth at these concentrations, while at 8 micrograms/ml it inhibited HTB 43 cell growth. Taxifolin slightly inhibited HTB 43 cell growth at 8 micrograms/ml, while moderately inhibiting HTB 43 cell growth at 2-8 micrograms/ml. The proliferation of a human lung fibroblast-like cell line (CCL 135) was relatively insensitive to low concentrations of the above flavonoids.  相似文献   
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A comparative study of 99Tcm-hexamethylpropyleneamine oxime (HMPAO) and 111In leucocyte scintigraphy was performed in inflammatory bowel disease. Two hundred and thirty-four patients were studied, 146 had 99Tcm-HMPAO, 82 had 111In and six had both. The sensitivity, specificity and accuracy of the 99Tcm leucocyte scan were 96, 97 and 97%, respectively, and 96, 97 and 97%, respectively, for the 111In leucocyte scan. 99Tcm-HMPAO leucocytes demonstrated similar diagnostic accuracy to 111In-labelled leucocytes with improved image quality and reduced radiation dose.  相似文献   
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