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51.
BACKGROUND: The association between raised levels of homocysteine, fibrinogen and lipoprotein (a), and the presence of pre-existing intimal hyperplasia (IH) in vein has not been assessed. The positive association between such hyperplasia and graft failure following infrainguinal arterial reconstruction, and between lipoprotein (a) and graft failure, is disputed. The influence of homocysteine on outcome has not been investigated prospectively. METHODS: Fifty-seven patients (63 grafts) undergoing infrainguinal arterial reconstruction with saphenous vein were studied. Homocysteine, fibrinogen and lipoprotein (a) levels were measured, and a vein biopsy was taken at operation. Patients underwent graft surveillance and outcome at 12 months was determined. RESULTS: Fifty-seven per cent of patients had hyperhomocysteinaemia. Patients with pre-existing IH had significantly higher homocysteine levels. There was no association between homocysteine and outcome, or between fibrinogen and pre-existing IH or outcome. Lipoprotein (a) levels were significantly lower in patients with pre-existing disease, and were lower, but not significantly, in those whose grafts failed. The correlation between pre-existing IH and vein graft failure was highly significant. CONCLUSION: Hyperhomocysteinaemia is associated with peripheral vascular disease and the development of pre-existing IH in vein, which itself is associated with vein graft failure. 相似文献
52.
Byrne JM Connolly JF MacLean SE Dooley JM Gordon KE Beattie TL 《Developmental medicine and child neurology》1999,41(11):740-747
To test the validity of a new computerized task to assess children's receptive vocabulary, event-related potentials (ERPs) were recorded from 56 typically developing children ranging in age from 5 to 12 years. This ERP-computerized vocabulary task does not require a child to give a verbal or motor (i.e. pointing) response. Single pictures, from an existing standardized test of receptive vocabulary, were presented on a computer screen and simultaneously named either correctly (congruent) or incorrectly (incongruent) via a computer. As predicted, the N400 amplitude was found to be significantly higher to the incongruent picture-word pair (i.e. the child knew it was an incorrect pairing) than to the congruent picture-word pair (i.e. the child knew it was a correct pairing). This effect was found for each of the four age groups (5 to 6 years, 7 to 8 years, 9 to 10 years, 11 to 12 years). This task accurately estimated current receptive vocabulary in typically developing children. Although still in the development stage, it may eventually serve as an adjunct to a thorough neurological and neurodevelopmental assessment of some children presenting with moderate to severe cerebral palsy. 相似文献
53.
We investigated the epidemiology, assessment and outcome of acute atraumatic limp in 243 children under the age of 14 years presenting to a paediatric accident and emergency department (AED) over a period of six months. Data were collected at presentation and medical notes were re-examined after 18 to 21 months. The incidence of limp was 1.8 per thousand. The male:female ratio was 1.7:1 and the median age 4.35 years. Limp was mainly right-sided (54%) and painful (80%); 33.7% of the children had localised pain in the hip. A preceding illness was found in 40%. The main diagnosis was 'irritable hip'/transient synovitis (39.5%); Perthes' disease accounted for 2%. Most patients (77%) were managed entirely in the AED. Acute atraumatic limp is a common problem in children presenting to the AED. Most can be safely managed there if guidelines are followed and will have a benign outcome. Further studies are needed to identify the role of preceding illness in the aetiology of acute atraumatic limp. 相似文献
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This article contributes to bridging the gap between research activity and the practical implementation of management decision making in the health sector by reflecting upon some of the issues and dilemmas for researchers, whether academics or managers, in conducting qualitative research in this sector. The article presents the methodological issues addressed by a team of researchers engaged on a project about manager learning and development in an NHS Trust, and highlights concerns about ethical issues that emerged from the research process. The study had involved a series of interviews with senior managers and clinical staff, doctors, nurses and therapists, and it addressed issues surrounding change within the organization, the impact on individuals' jobs, and the resultant learning and development required and undertaken. The article emphasizes that engaging in reflection on the research process is valuable and suggests that it should become a mainstream part of such research. It concludes that there is an important role of qualitative management research in the health sector and that for it to be acceptable and valued, it must be operationally sensitive, ethically robust and methodologically rigorous. 相似文献
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LH-RH causes pregnancy failure in hypophysectomized rats. This study investigated whether this failure was due to an action of LH-RH upon the fetus, placenta, uterus, or ovary. Pseudopregnant, hypophysectomized, prolactin treated rats were subjected to uterine trauma to develop the decidual cell response or were hysterectomized. Deciduoma formation and serum progesterone valves were significantly decreased in all LH-RH treated animals. These observations suggest that LH-RH inhibits prolactin maintained progesterone secretion in hypophysectomized rats by a direct action of the hormone on the ovary. 相似文献
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59.
This study was designed to determine the effect of prolonged infusion on the ease of reversal of atracurium and vecuronium, and whether factors which potentiate the block delayed reversal. In phase one, 40 patients were randomized (double blind) to determine the steady state conditions for atracurium and vecuronium. Fourteen atracurium patients and 17 vecuronium patients were evaluable. The unblinded second phase involved the steady state conditions using halothane or isoflurane and atracurium infusions. The infusion required for 95% twitch depression (TD95) for atracurium was 7.6 +/- 1.1 micrograms.kg-1 x min-1. The requirement for vecuronium changes with time: TD95 at 30 min was 1.01 +/- 0.16, at 60 min 0.89 +/- 0.12 and after 90 min 0.85 +/- 0.17 micrograms.kg-1 x min-1 (P < 0.05). The mean TD95 was 0.94 +/- 0.23 micrograms.kg-1 x min-1. Multivariate regression analysis of the infusion data revealed a vecuronium model predicting TD95 by the duration of infusion (P < 0.05) and weight (P = 0.05). Atracurium TD95 was predicted by age (P = 0.05). The addition of an inhalation agent to atracurium reduced the infusion rate by 2.01 +/- 0.28 micrograms.kg-1 x min-1 (P = 0.0001) for each increase in MAC. The mean reversal times for atracurium with three different anaesthetics and for vecuronium were not different. Reversal of pancuronium blockade, from less profound twitch depression (86.4 vs 95%) took twice as long as for atracurium and vecuronium for which the following predictors were identified: age, weight, duration of infusion, level of blockade, and type of anaesthetic, using a stepwise regression model.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
60.
B C Campbell A D Beattie H L Elliott A Goldberg M R Moore D G Beevers M Tree 《Archives of environmental health》1979,34(6):439-443
Hypertension may result from chronic lead exposure. Lead poisoning arising from "moonshine whiskey" drinking has been associated with a rise in plasma renin activity. In the present study, plasma renin concentration following intravenous administration of frusemide was measured in eleven subjects with moderate or severe lead poisoning of industrial origin. The results were compared with those obtained for seven normal, control subjects. There was no significant difference in response obtained in the two groups. Industrial lead poisoning does not appear to affect renin release. The combined insult of lead and alcohol may explain the findings in the previous study. 相似文献