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Searching for randomised controlled trials and clinical controlled trials in Thai online bibliographical biomedical databases 总被引：1，自引：1，他引：0
Background: Thailand is a poor but highly literate country in South‐East Asia with over 60 million people. A lot of biomedical research is undertaken but dissemination is limited. Objectives: To identify relevant Thai bibliographic databases and investigate accessibility, functionality and content, particularly in relation to randomised controlled trials (RCTs) and clinical controlled trials (CCTs). Methods: A systematic search for institutions productive of research and the databases in their libraries. Search each accessible database in both Thai and English, recording the functionality and content. Assess accessibility of the retrieved RCTs or CCTs by comparing to Pub Med holdings. Results: We found 32 different databases (29 accessible in UK) of various sizes, coverage and functionality but many with unique records of RCTs and CCTs (total, n = 781). Two hundred and nine of 781 trials were accessible on Pub Med (27%). However, 641 of the 781 trial records contain text in both English and Thai (82%) and 112 records were solely English (14%). Conclusions: Those undertaking comprehensive searches for RCTs/CCTs should, in addition to a Pub Med , search the Thai Medical Index and Thai Index Medicus databases, and the Khon Kaen University Library Catalogue. 相似文献
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Adams Edwin P. 《Journal of The Franklin Institute》1927,204(4):469-486
(I) Evidence has been given that the so-called permanent electrets of Eguchi are not permanent, but that their polarization decays with the time. At room temperatures this decay is too slow to be observed directly; but it is the decay of the polarization that, at least in part, accounts for the presence of the free charges that are always observed. At higher temperatures the results that have been obtained are consistent with the view that the rate of decay of the polarization increases very rapidly with the temperature; so much so that the polarization may be almost completely destroyed at a temperature which is not high enough to cause any appreciable softening of the waxes that form the substance of the electrets.(2) As is to be expected from Lord Kelvin's hypothesis as to the cause of pyro-electricity, these electrets have been shown to possess the pyro-electric property.(3) The piezo-electric effect, which always accompanies the pyro-electric property, has been shown to be exhibited by these electrets. 相似文献
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