Burnout among general practitioners, a systematic quantitative review of the literature on determinants of burnout and their ecological value.

Burnout is a major social and economic problem, specifically among general practitioners (GPs). The amount of literature on generic determinants of burnout is impressive. However, the size of the library on occupation-specific determinants of burnout among GPs are minimal.

Brassinosteroid biosynthesis and signalling in Petunia hybrida.

Brassinosteroids (BRs) are steroidal plant hormones that play an important role in the growth and development of plants. The biosynthesis of sterols and BRs as well as the signalling cascade they induce in plants have been elucidated largely through metabolic studies and the analysis of mutants in Arabidopsis and rice. Only fragmentary details about BR signalling in other plant species are known.

Nod factor and elicitors activate different phospholipid signaling pathways in suspension-cultured alfalfa cells.

Lipo-chitooligosaccharides (Nod factors) are produced by symbiotic Rhizobium sp. bacteria to elicit Nod responses on their legume hosts. One of the earliest responses is the formation of phosphatidic acid (PA), a novel second messenger in plant cells.

Observations on the iron status during pregnancy in rats. Iron transport from mother to fetus.

The objective of the present study was to investigate a transfer of liver iron in rats from mother to fetus during pregnancy. A decrease in maternal liver iron and an increase in fetal liver iron, in groups of 10 rats, have been shown, based on iron analysis and specific activity of 59Fe.

Heme synthetase activity in normal human and rat erythroid cells and in sideroblastic anemia.

The enzyme heme synthetase, involved in the final step of the biosynthesis of heme, has been assessed in rat and human bone marrow and peripheral blood. The pH optimum of the enzyme in bone marrow appeared to be pH 7.6, whereas the Michaelis constant in human and rat bone marrow was found to be 1.

Functional heterogeneity of transferrin-bound iron: iron uptake by cell suspensions from bone marrow and liver and by cell cultures of fibroblasts and lymphoblasts.

According to the hypothesis of Fletcher and Huehns, functional differences exist between both iron-binding sites of transferrin. The site designated A should mainly be involved in the delivery of iron to erythroid cells, whereas site B should donate its iron preferentially to cells involved in the absorption and storage of iron. In the present study this hypothesis could be confirmed by in vitro experiments with various cell types.

Isolation, characterization and function of cord-blood transferrin.

1. Transferrin was isolated from umbilical cord blood by means of gel filtration on Sephadex G-150 and ion exchange chromatography on DEAE-Sephadex A-50, and its properties were compared with those of transferrin isolated from human adult blood. 2.

The difference between the glucose concentrations in plasma and whole blood.

The glucose concentrations in whole blood (WB) and plasma (P), both prediluted with distilled water and saline, and in their protein-free filtrates, were determined with the Hoffman ferricyanide method. In whole blood prediluted with distilled water the glucose concentration appeared to be 13% higher than in whole blood prediluted with saline. In plasma, predilution with distilled water or saline did not result in different glucose values.