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1.
A E van der Merwe F J Mattheyse M Bedford P D van Helden D J Rossouw 《Burns : journal of the International Society for Burn Injuries》1990,16(3):193-197
Cultured keratinocytes were used as allografts on burn wounds in two patients. In both patients successful covering of the wounds was obtained. DNA fingerprinting of the epidermis covering the wounds 21 days later showed that the cultured keratinocytes were replaced by the patients' cells. 相似文献
2.
Ann Bowling Morag Farquhar Emily Grundy Juliet Formby 《International journal of geriatric psychiatry》1992,7(5):307-321
This article reports findings from a longitudinal survey of very elderly people living at home in London. The research aimed to identify social, psychological and physical characteristics associated with positive ageing and successful survival in the community in later life and its converse—negative ageing—as well as the associated policy implications. Associations with psychiatric morbidity, measured using the General Health Questionnaire, among sample members without cognitive impairment between the baseline interviews in 1987 and at follow-up, two and a half years later in 1990, are reported. Twenty-five per cent of survivors scored over the threshold of the GHQ in 1987 and 30% scored over the threshold in 1990. Half of those with a score over the threshold in 1990 also scored over the threshold in 1987. Hierarchical regression (using residualized change analysis) was used to estimate the effects of the independent variables on changes in psychiatric morbidity. The most significant predictor of psychiatric morbidity (GHQ score) in 1990 was baseline GHQ score, followed by health and functional status scores. Health and functional status were also the strongest predictors of baseline (1987) GHQ scores. The uniqueness of the study lies in the collection of follow-up data on a sample of very elderly people, given that most surveys are corss-sectional and contain too few people aged 85+ to merit separate analysis. It contributes to the small body of literature on outcome of depression. The lack of consistent associations with recovery from psychiatric morbidity in the literature enhances the importance of studies aiming to identify factors associated with different outcomes. 相似文献
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Chicks with genetically elevated renal arginase activity were fed crystalline amino acid diets varying in ornithine concentration (0, 1 or 2%) to assess the potential for precursor regulation of polyamine synthesis. Renal arginase and renal and hepatic ornithine decarboxylase activities fell when ornithine was fed. Renal and hepatic ornithine concentrations rose while putrescine concentrations varied quadratically with ornithine feeding. Spermidine and spermine concentrations were not affected by diet. It was concluded that ornithine synthesized in vivo was a more potent stimulator of polyamine synthesis than ornithine of dietary origin. 相似文献
5.
Julia E. Ledger MSc Graham J. Watson Dr. Juliet E. Compston MD 《Digestive diseases and sciences》1986,31(4):361-368
The biliary excretion of radioactivity after intravenous [3H]25-hydroxyvitamin D3 was studied in nine patients with T-tube bile drainage. The mean +/- SD 24-hr radioactivity excretion in T-tube bile expressed as a percentage of the administered dose was 6.7 +/- 2.9%; after correction for incomplete bile collection, the value obtained was 16.0 +/- 11.1%. Chloroform solubility of biliary radioactivity increased from 27.4 +/- 8.9% to 72.9 +/- 10.1% following incubation with beta-glucuronidase. High-performance liquid chromatographic analysis of chloroform extracts of bile revealed that most of the eluted radioactivity was more polar than [3H]25-hydroxyvitamin D3. No free [3H]25-hydroxyvitamin D3 was demonstrated. Thus in man, most of the biliary radioactivity excreted following [3H]25-hydroxyvitamin D3 is in the form of water-soluble compounds, mainly glucuronides. However, our results suggest that glucuronides of metabolites other than 25-OHD3 are predominantly formed. 相似文献
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We have developed a transient expression system for the protist Physarum polycephalum based on firefly luciferase. We demonstrate the utility of this system for comparing the activities of different promoters in Physarum amoebae, and also for detecting genetic elements that affect the level of gene expression. This system is likely to facilitate improvements in the stable transformation of this organism. 相似文献
10.
Adhesion molecules are upregulated on dendritic cells isolated from human blood. 总被引:2,自引:0,他引:2
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This study investigated whether the high expression of adhesion molecules on enriched preparations of circulating dendritic cells (DCs) was an intrinsic property of the cells or whether it was a consequence of the procedure used to isolate them from blood. Expression of the beta 1, beta 2 integrins (CD11/CD18 family) and other adhesion molecules on DCs in whole blood was compared with that on isolated DCs. Dendritic cells were identified by flow cytometry as leucocytes that were positive for human leucocyte antigen (HLA)-DR, but negative for CD3, CD14, CD16, CD19 and CD56. In contrast to a minority of DCs in whole blood, the majority of isolated DCs expressed the beta 2 integrins and there were a greater number of cells bearing CD44, CD54 and some of the beta 1 integrins (notably CD49b, CD49d, CD49e and CD29). An increase in the proportion of DCs bearing adhesion molecules was generally apparent at the isolation stage when mononuclear cells, which had been incubated overnight, were centrifuged on a metrizamide gradient to enrich for cells of low density. Inclusion of an inhibitor of protein glycosylation and exocytosis (brefeldin A) at all stages of separation partially prevented an increase in the percentage of DCs bearing CD18, C29 and C54 whereas the inclusion of cycloheximide (an inhibitor of polypeptide synthesis) interfered with increases in the percentage of cells bearing CD29 and CD54. Neither of these antagonists had an effect on the intensity of adhesion molecule expression. We suggest that some of the adhesion-dependent functions of isolated DCs are caused, in part, by an upregulation of surface adhesion molecules induced by the enrichment procedure. 相似文献