3-D finite element simulation for ultrasonic propagation in tooth.

Objectives: Ultrasonic testing of the tooth has been suggested as an alternative method of identifying dental pathology. Due to the complex geometry and low transmission efficiency of ultrasonic signals in tooth structures, it is difficult to establish one-to-one correspondence between ultrasonic behaviour and specific tooth pathologies both in vitro and in vivo. In order to facilitate ultrasonic diagnosis in dental applications, finite element modeling (FEM) was used to simulate ultrasonic wave propagation in teeth with several dental conditions.

[Cellular immunity in dialysis patients using the lymphocyte transformation test (LTT) in comparison to conservatively treated patients with chronic terminal renal failure].

By means of the lymphocyte transformation test (LTT), using the mitogens phytohemagglutinin (PHA), concanavalin A (ConA), lipopolysaccharide (LPS) E. coli and the antigens tuberculin (PPD) and O-streptolysin, a contribution should be made for the judgment of the functional capacity of the immune system--in particular of the cellular immunity--in uraemia patients with and without dialysis therapy. In 33 patients with different duration of the dialysis (0.