A university hospital plays roles as a specific functional hospital and as a teaching hospital in primary care because most medical school graduates receive basic clinical training in this area. An important objective of primary care education for all residents is the initial treatment of patients with first-to third-level emergencies. We examined the number of patients, the level of emergency (first, second, and third level) and the diagnoses that each resident encountered. Subjects included 29 residents (3 in the first year, 4 in the second year, and 2 in the third year) who had undergone clinical training for 3 months in the department of emergency medicine at the Saga Medical School Hospital which treats 7, 000 to 8, 000 patients per year with first-to third-level emergencies. Residents were involved with 214.6 emergency cases, which included approximately 59 types of first-level emergency, 31 types of second-level emergency, and 15 types of third-level emergencies. These results were largely compatible with the Objectives of Postgraduate Basic Clinical Training proposed by the Japan Society for Medical Education. These results show that university hospitals as specific functional hospitals should accept numerous emergency patients and that residents must receive clinical training in emergency medicine to achieve the objectives of primary care education.

OBJECTIVETeeth can serve as records of environmental exposure to heavy metals during their formation. We applied a new technology - synchrotron radiation microbeams (SRXRF) - for analysis of heavy metals in human permanent teeth in modern and historical samples.

METHODSEach tooth was cut in half. A longitudinal section 200 mum in thickness was subjected to the determination of the heavy metal content by SRXRF or conventional analytical methods (ICP-MS analysis or reduction-aeration atomic absorption spectrometry). The relative concentrations of Pb, Hg, Cu and Zn measured by SRXRF were translated in concentrations (in g of heavy metal/g of enamel) using calibration curves by the two analytical methods.

RESULTSConcentrations in teeth in the modern females (n = 5) were 1.2 +/- 0.5 mug/g (n = 5) for Pb; 1.7 +/- 0.2 ng/g for Hg; 0.9 +/- 1.1 mug/g for Cu; 150 +/- 24.6 mug/g for Zn. The levels of Pb were highest in the teeth samples obtained from the humans of the Edo era (1603-1868 AD: ) (0.5-4.0 mug/g, n = 4). No trend was observed in this study in the Hg content in teeth during 3,000 years. The concentrations of Cu were highest in teeth of two medieval craftsmen (57.0 and 220 mug/g). The levels of Zn were higher in modern subjects (P < 0.05) than those in the Jomon (~1000 BC: ) to Edo periods [113.2 +/- 27.4 (mug/g, n = 11)]. Reconstruction of developmental exposure history to lead in a famous court painter of the Edo period (18th century) revealed high levels of Pb (7.1-22.0 mug/g) in his childhood.

CONCLUSIONSSRXRF is useful a method for reconstructing human exposures in very long trends.