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1.
Bradykinin-induced release of PGI2 from aortic endothelial cell lines: responses mediated selectively by Ca2+ ions or a staurosporine-sensitive kinase. 下载免费PDF全文
1. Bradykinin (100 nM) triggers release of nitric oxide and prostacyclin from both AG07680A and AG04762 bovine cultured aortic endothelial cells. The exposure of these cells to bradykinin is in each case associated with a striking rise in intracellular calcium ion concentration. 2. Exposure of AG07680A cells to 250 nM ionomycin was followed also by a significant release of prostacyclin, whereas 250 nM ionomycin had no capacity to stimulate release of prostacyclin from AG04762 cells. 3. There was a similar concentration-dependent increase in intracellular calcium ion concentration on exposure of AG07680A and AG04762 cells to ionomycin. 4. Exposure of AG04762 cells for 10 min to staurosporine produced a concentration-dependent inhibition (IC50 = 107 +/- 14 nM) in bradykinin-stimulated prostacyclin release. There was no similar inhibitory effect of staurosporine in AG07680A cells. 5. Bradykinin (10 nM) triggered release of nitric oxide from both AG07680A and AG04762 cells, and the effect was not inhibited by 500 nM staurosporine. There was a similar ionomycin-dependent release of nitric oxide from both cell types. 6. These results identify a common pathway for bradykinin-dependent nitric oxide release from both AG07680A and AG04762 cells, involving increases in intracellular calcium ion concentration. In contrast, the bradykinin-dependent release of prostacyclin may involve one of two pathways (involving an increase in intracellular calcium or activation of a staurosporine-sensitive kinase), and the two pathways are selectively exploited in AG07680A and AG04762 cells, respectively. 相似文献
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3.
Pyomyositis: characteristics at CT and MR imaging 总被引:9,自引:0,他引:9
4.
Action of calcitonin gene-related peptide upon bovine vascular endothelial and smooth muscle cells grown in isolation and co-culture. 总被引:3,自引:2,他引:1 下载免费PDF全文
D. C. Crossman M. R. Dashwood S. D. Brain J. McEwan J. D. Pearson 《British journal of pharmacology》1990,99(1):71-76
1. Bovine aortic endothelial cells (BAE) and smooth muscle cells (BASM) were grown separately and in co-culture. 2. Calcitonin gene-related peptide (CGRP) caused dose-dependent activation of adenylate cyclase in each cell type when grown in isolation. The concentration of CGRP causing half-maximal activation in BAE and BASM was 200 nM and 310 nM, respectively. 3. In cells grown in co-culture exposure to bradykinin produced dose-dependent elevations in cyclic GMP content which were maximal 1 min after application of the agonist. 4. CGRP (1 nM-1 microM) did not stimulate a rise in cyclic GMP in co-cultures. 5. Displaceable CGRP binding was identified throughout the wall of the bovine aorta. 6. We conclude that CGRP receptors coupled to adenylate cyclase are present on BAE and BASM, but there is no coupling of these receptors to the release of any agent (such as endothelium-derived relaxing factor) that activates guanylate cyclase. 相似文献
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D De AJ Kanwar S Handa 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):853-859
BACKGROUND: Diagnosis of atopic dermatitis (AD) depends on clinical features because no definitive diagnostic test exists. Criteria proposed by Hanifin and Rajka (Acta Derm Venereol (Stockh) 1980; Suppl 92: 44-47) were acceptable for hospital-based studies but were found not to be suitable for field studies. A UK working party formulated clinical diagnostic criteria that could be used in both hospital and epidemiological settings. Validation studies of the criteria showed widely variable results, probably due to different clinical settings and ethnicity. AIM AND OBJECTIVE: This study was undertaken to validate Hanifin and Rajka's criteria and to assess the comparative efficacy of their criteria and the UK working party's diagnostic criteria in the diagnosis of AD in a hospital setting in North India. SUBJECTS AND METHODS: This study serially included 101 patients with AD and 48 controls of paediatric age group. The study period was from July 2003 to December 2004. RESULTS: Hanifin and Rajka's criteria (sensitivity 96%, specificity 93.75%, positive predictive value 97% (PPV) and negative predictive value (NPV) 91.84%) had a statistical advantage over the UK working party's diagnostic criteria (sensitivity 86%, specificity 95.83%, PPV 97.75% and NPV 76.67%), with a P-value < 0.005. 相似文献
7.
P. von Dadelszen Gynaecology Registrar M. D. G. Gillmer Consultant Gynaecologist M. D. Gray Consultant Gynaecologist H. P. McEwan Consultant Gynaecologist R. J. D. Pyper Consultant Gynaecologist T. P. Rollason Consultant Pathologist A. Wright Gynaecology Registrar 《BJOG : an international journal of obstetrics and gynaecology》1994,101(2):158-161
8.
This is the third report of a metabolic study on 56 long-term users (24 for 2-5 yr; 32 for over 5 yr) of the injectable contraceptive norethisterone enanthate (Net-En) and deals with the effects on the blood levels of lipoprotein fractions. There was no significant difference between this group and a group of 30 non-users in serum concentrations of triglycerides, total cholesterol, low density and very low density lipoproteins. There was a significant reduction in mean high density lipoprotein levels between the controls and the user groups (16% for the intermediate duration and 12% for the longer duration). Age, ethnic group, body-mass index and a close family history of cardiovascular disease were taken into account, as were various lifestyle factors: diet, exercise, alcohol consumption and smoking. In a smaller group, levels of apoproteins A and B were also assayed. There was a significant reduction in apoprotein A between controls and all users, but the significance was lost on adjusting for confounding variables. Consideration was given to the ratio of total cholesterol to high density lipoprotein cholesterol as an index of coronary risk. There were no significant differences in the total cholesterol:HDL-C ratio between controls and user groups. There was a significant interaction with ethnic group (Caucasian or Afro-Caribbean) in the response to duration of use. 相似文献
9.
C. Constanzo I. T. Jackson C. McEwan J. M. Self 《European journal of plastic surgery》1987,9(4):137-140
Summary The clinical features and histological appearance of desmoplastic malignant melanoma are presented. Aggressive surgical management and close follow-up are mandatory if this highly aggressive tumor is to be controlled. Despite this, the prognosis is poor. 相似文献
10.
Kuntal Patel Deemesh Oudit G Ross Caroline Nicolson AJ Howcroft 《CANADIAN JOURNAL OF PLASTIC SURGERY》2005,13(4):207-208
A lump on the midface of a child can pose as a diagnostic dilemma. There is a wide variety of possible differential diagnoses, ranging from simple benign conditions such as a sebaceous cyst, dermoid cyst, lipoma, neuroma and neurofibroma, to potentially devastating conditions such as odontogenic myxoma.A case of a child in which the formulation of a definite diagnosis was clinically and histologically challenging is presented. 相似文献