Expression of arthropod distal limb-patterning genes in the onychophoran Euperipatoides kanangrensis.

A current hypothesis states that the ancestral limb of arthropods is composed of only two segments. The proximal segment represents the main part of the modern leg, and the distal segment represents the tarsus and claw of the modern leg. If the distal part of the limb is an ancestral feature, one would expect conserved regulatory gene networks acting in distal limb development in all arthropods and possibly even their sister group, the onychophorans.

Chromic acid poisoning treated with acute hemodialysis.

Poisoning with chromium compounds is rare, but often serious. The symptoms are quite characteristic, the most dramatic of these being circulatory collapse, hepatic and renal failure. A case is reported where an 18-year-old woman ingested 5 g of chromic acid.

KINETICS OF SERUM AMINOSALICYLIC ACID LEVELS.

A mathematical model, involving three consecutive first order reactions, has been applied to already existing experimental material in order to explain the hourly variation in serum levels obtained after administration of varying repeated doses of different preparations of p-aminosalicylic acid to human volunteers. The model closely agrees with the experimental data for all the orally administered preparations concerned, and the differences in blood levels for different preparations can be explained in terms of the values attributed to the parameters involved in the model. The same model adequately describes the elimination of aminosalicylic acid from the blood after a single intravenous infusion provided that the initial blood level attained does not exceed about 11 mg/100 ml.