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A Calatayud

Publications and source records attributed to A Calatayud.

5 recordsLinked to original sources

Cancer mortality and exposure to chemical carcinogens in the work place: an ecological study in the Valencian Community, Spain (1981-1995).

To evaluate the geographical distribution of the mortality from malignant tumours in relationship with exposure to chemical carcinogens in the work place, and to asses the possible association between these questions and the percentage of population employed in certain high-risk sectors, an ecological study in the Valencian Community (VC), Spain was carried out. Age-adjusted mortality rates for the total number of malignant tumours, lung, bladder, lymphomas and leukaemia during the periods 1981-1985 and 1991-1995 were calculated for the 34 geographical areas. The percentage of population in each area working in sectors in which they may be exposed to chemical carcinogens was obtained. The relationship between mortality on-the-job exposure was studied using linear regression methods. Large differences in cancer mortality were seen. In men, the geographical pattern was very stable and reveals a significant association with the distribution of certain high-risk jobs. Statistically significant positive correlations (p < 0.001) were found between cancer mortality and the percentage of the population working in metal, wood and furniture sectors. In contrast, a negative and statistically significant (p < 0.001) correlation was observed between cancer mortality and the percentage of the population working in agriculture. In conclusion, although the variability in cancer mortality in men was significantly associated with some occupational sectors in the VC, caution is needed when drawing conclusions about causation from ecological studies.

Agriculture↗

Determination of L-ascorbic acid and total ascorbic acid in vascular and nonvascular plants by capillary zone electrophoresis.

A capillary zone electrophoresis (CZE) procedure for the determination of l-ascorbic acid (AA) and total ascorbic acid (TAA, as the sum of AA and dehydroascorbic acid) in vascular plants, lichens, bryophytes, and liverworts is described. The samples were frozen in liquid nitrogen and extracted with 2% metaphosphoric acid. To determine AA, an aliquot was directly injected in a fused-silica capillary. The determination of TAA was performed upon its reduction with dl-homocysteine at pH 7. The background electrolyte contained 60 mM sodium chloride, 60 mM sodium dihydrogen phosphate, 1 x 10(-4)% hexadimetrine bromide, and NaOH up to pH 7. The procedure was rapid and highly reproducible; the limit of detection was 0.2 microg ml-1, which corresponded to 0.4 mg/100 g of sample. The method was validated by comparison with an enzymatic assay. While the enzymatic assay failed to quantify AA in some plants owing to strong background UV absorption, CZE was successful in all the extracts assayed.

Ascorbic Acid↗

Massive arterial bleeding from a single rectal vessel.

We report a case of massive rectal haemorrhage arising from a single ectatic arterial vessel above the haemorrhoidal cushion in normal rectal mucosa. Use of an anal retractor enable identification of the bleeding vessel and avoided a major laparatomy.

Aged↗