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One feature that contraindicates the wide therapeutic use of natural retinoids is their adverse effects during systemic use and the lack of receptor selectivity. In contrast, synthetic retinoids are distinguishable from each other on the basis of their partial or exclusive preference in binding and activation of selective retinoid receptors. We examined the inhibitory activities of natural and synthetic retinoids for their ability to reverse basic fibroblast growth factor-induced endothelial cell proliferation. Both the naturally occurring retinoids at nanomolar concentrations reversed basic fibroblast growth factor-induced endothelial cell proliferation. Among the synthetic retinoids tested, retinoic acid receptor/retinoid x receptor pan-agonist AGN 191659 [(E)-5-[2-(5,6,7, 8-tetrahydro-3, 5,5,8,8-pentamethyl-2-naphtyl) propen-1-yl]-2-thiophenecarboxylic acid] and retinoid x receptor pan-agonist AGN 191701 [(E)-2-[2-(5,6,7,8-tetrahydro-3, 5,5,8, 8-pentamethyl-2-naphthyl) propen-1-yl]-4-thiophenecarboxylic acid] at nanomolar concentrations reversed the basic fibroblast growth factor-induced endothelial cell proliferation. Since none of the retinoic acid receptor agonists tested had any effect, the inhibitory effect of AGN 191659 could be attributed to its retinoid x receptor receptor activity. These results suggest that retinoid x receptor agonists may be more selective anti-angiogenic agents due to their ability to inhibit endothelial cell proliferation. 相似文献
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Daan P Livestro Alona Muzikansky Emily M Kaine Thomas J Flotte Arthur J Sober Martin C Mihm James S Michaelson A Benedict Cosimi Kenneth K Tanabe 《Journal of clinical oncology》2005,23(27):6739-6746
PURPOSE: Previous studies have established that patients with desmoplastic melanoma (DM) have thicker primary tumors. Consequently, comparisons with other forms of melanoma have been strongly biased by differences in Breslow stage. This is the first case-matched control study comparing DM with other forms of melanoma. PATIENTS AND METHODS: From a database of 3,202 melanoma patients treated at one institution, 89 patients with DM and 178 case-matched control patients (2:1) were identified by matching for tumor thickness, age, sex, and year of diagnosis. Clinical, pathologic, and outcome information was obtained from chart review. RESULTS: Controls were matched successfully to patients for tumor thickness, age, sex, and year of diagnosis. Presentation with American Joint Committee on Cancer stage III or IV disease is less common in patients with DM compared to case-matched control patients (5% v 21%; P < .001). Re-excisions to obtain clear surgical margins are required more often in patients with DM compared to case-matched control patients (21% v 6%; P < .001). Risk of positive sentinel nodes is lower in patients with DM compared to case-matched control patients (8% v 34%; P = .013). Despite these differences, survival rates of patients with DM are the same as case-matched control patients. CONCLUSION: Use of case-matched control patients matched for tumor thickness avoids biases introduced by the advanced Breslow stage of DMs. DMs are more locally aggressive than thickness-matched controls, and positive sentinel nodes are limited to patients with thick primary tumors. Importantly, patients with DM have survival rates similar to patients with other melanomas of similar thickness. 相似文献
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Suzanne Robinson Iestyn Williams Helen Dickinson Tim Freeman Benedict Rumbold 《Social science & medicine (1982)》2012
In a context of ever increasing demand, the recent economic downturn has placed further pressure on decision-makers to effectively target healthcare resources. Over recent years there has been a push to develop more explicit evidence-based priority-setting processes, which aim to be transparent and inclusive in their approach and a number of analytical tools and sources of evidence have been developed and utilised at national and local levels. This paper reports findings from a qualitative research study which investigated local priority-setting activity across five English Primary Care Trusts, between March and November 2012. Findings demonstrate the dual aims of local decision-making processes: to improve the overall effectiveness of priority-setting (i.e. reaching ‘correct’ resource allocation decisions); and to increase the acceptability of priority-setting processes for those involved in both decision-making and implementation. Respondents considered priority-setting processes to be compartmentalised and peripheral to resource planning and allocation. Further progress was required with regard to disinvestment and service redesign with respondents noting difficulty in implementing decisions. While local priority-setters had begun to develop more explicit processes, public awareness and input remained limited. The leadership behaviours required to navigate the political complexities of working within and across organisations with differing incentives systems and cultures remained similarly underdeveloped. 相似文献
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Alison M. Rich Benedict Seo Venkata Parachuru Haizal M. Hussaini 《Periodontology 2000》2017,74(1):176-181
A wide variety of lesions may arise from the oral mucosa, fibrous connective tissue, bone and cementum of the periodontium. The commonest pathology occurs as a result of bacterial infection and is very well known to dentists and periodontists, but rarer conditions present as gingival pathology. The pathogenesis of these conditions ranges from genetic to traumatic to immunological to neoplastic, and includes benign, malignant and metastatic lesions. This paper outlines some of these conditions and describes how the periodontist and oral pathologist can work together using a framework, and how with careful consideration of the clinical features and the use of appropriate special tests, including obtaining an adequate tissue specimen, a timely and accurate diagnosis can be obtained. 相似文献