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11.
The present study was undertaken to: (a) clarify the comparative renal potency of bolus injection of the natriuretic peptides urodilatin and ANF99-126 in the rat; (b) establish whether or not intravenous (i.v.) infusion of urodilatin (200 ng/min) combined with dopamine (UD) to maintain mean arterial pressure could improve GFR or renal histology in established experimental ischemic acute renal failure (ARF) induced by 30 minutes of bilateral renal artery clamping; (c) assess comparative efficacies of nitroprusside, an activator of soluble guanylate cyclase, combined with dopamine (ND) or control infusions of dopamine alone (DA), under equivalent conditions; and (d) determine effects of intra-renal arterial infusions of the stable cGMP analogue dibutyryl-cGMP immediately after renal artery clamping (RAC). After initial dose finding studies, i.v. infusion of UD 24 hours after 30 minutes of RAC improved GFR over five hours from 0.24 +/- 0.04 to 1.0 +/- 0.16 ml/min in association with a threefold rise in plasma cGMP and a 13-fold increase in urinary cGMP excretion. Plasma creatinine dropped by 41% from 230 +/- 16 to 135 +/- 18 microM/liter and was still reduced 24 hours later with values averaging 106 +/- 14 compared to 274 +/- 53 microM/liter in non-treated animals. During infusion, UV and FENa+ increased from 1.4 +/- 0.2 to 8.3 ml/min, and from 2.9 +/- 0.5 to maximum values of 15.8 +/- 2.4%. ND or DA alone were less effective, increasing GFR only to 14 and 20%, respectively, of normal values, but improvements were not sustained; in contrast to UD, ND did not alter plasma or urinary cGMP. In addition, DBcGMP was ineffective in improving GFR during early ARF. Histologically UD, but not ND, markedly reduced the incidence of granular casts, tubular desquamation and tubular necrosis in cortical areas and increased the incidence of medullary mitoses. 相似文献
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R C Ayres S G Hübscher J Shaw C Garner R Joplin A Williams J M Neuberger 《The Journal of pathology》1991,165(2):153-161
We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described. 相似文献
13.
S J McLoughlin S J Shaw S Turner B S Sylvester 《The Journal of hand surgery, European volume》1990,15(1):129-130
A case is described in which a deep palmo-planar wart (myrmecia) caused erosion of the underlying phalanx. 相似文献
14.
D R Sandeman A P Sandeman P Buxton H H Hughes D W Chadwick I R Williams R D Baker P M Foy D M Shaw 《British journal of neurosurgery》1990,4(4):299-312
The management of patients presenting with supratentorial glioma between 1978 and 1986 is reviewed. Complete follow-up in 517 cases was obtained. One hundred and fifty eight patients were not submitted to any form of surgery, 299 patients were biopsied and 60 patients underwent craniotomy and internal decompression. The no surgery group contained a higher proportion of patients with poor prognostic indicators than either the biopsy or craniotomy groups. The craniotomy group consisted of patients with better prognostic indicators than the biopsy group, in particular, younger age and more favourable site, type and grade of tumour. This was reflected in the difference in outcome between the groups. Median survival was 14 months in the craniotomy group, four months in the biopsy group and 2.2 months in the no surgery group. The outcome in patients with histologically proven malignant gliomas was best in those patients who received radiotherapy. The craniotomy group had a median survival of 18.5 months, a two year survival of 48% and a five year survival of 9%. The median survival following radiotherapy of those patients with proven malignant gliomas who had a biopsy was 9.5 months with a two year survival of 16% and a five year survival of 2%. These results compare favourably with studies which have adopted a more aggressive approach, suggesting that outcome is determined as much by patient selection using favourable prognostic indicators as by the treatment itself. The need for prospective trials of the management of unselected consecutive glioma patients randomizing them to conservative and radical treatment groups in order to define the role of both conventional therapy and radical therapy is discussed. 相似文献
15.
目的探讨原发性高血压(EH)患者微量白蛋白尿(MCA)与血压及左室重塑的关系.方法 84名EH患者按24h尿微量白蛋白值分为微量白蛋白尿组(MCA组)和正常白蛋白尿组(NMCA组),进行动态血压、心脏超声检测,比较两组动态血压值、左室重量指数(LVMI)及左室重塑的特点.结果 MCA组平均收缩压、平均舒张压、脉压、平均动脉压均高于NMCA组(均P<0.01);MCA组LVMI、左室肥厚与向心性肥厚的发生率均高于NMCA组(均P<0.01),正常构型率低于NMCA组(P=0.01).LVMI与尿微量白蛋白值、平均收缩压、平均舒张压均呈显著的正相关(均P<0.05).结论合并有MCA的EH患者血压较高,LVMI较大,左室肥厚与向心性肥厚的发生率较高.MCA与血压及左室重塑密切相关. 相似文献
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Rosa M. Razaboni M. Alba Greco Alice D. Harper William W. Shaw Donald L. Ballantyne 《Microsurgery》1981,3(2):65-71
Segments 15 mm in length were excised from the femoral veins of rats and preserved by refrigeration at 4 C in lactated Ringer's solution for periods up to 21 days. The findings show that veins can be preserved for up to seven days and successfully grafted to recipients. Although there was some success in preserving vein segments for more than seven days, a high rate of thrombosis occurred after implantation in the recipients. It is generally accepted that damaged endothelium causes thrombosis. The light and electron microscopic observations in this study, however, suggest that the condition of the endothelium may not be the only important factor in the patency of small vessels. A thickened and prominent elastic lamina may also play a role in keeping the lumen open. 相似文献
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Kevin O'Brien Jean Wright Frances Conboy YeWeng Sanjie Nicky Mandall Stephen Chadwick Ivan Connolly Paul Cook David Birnie Mark Hammond Nigel Harradine David Lewis Cathy McDade Laura Mitchell Alison Murray Julian O'Neill Mike Read Stephen Robinson Dai Roberts-Harry Jonathan Sandler Ian Shaw 《American journal of orthodontics and dentofacial orthopedics》2003,124(3):234-43; quiz 339
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant. 相似文献