Cancer registries in Australia

Cancer registries are at an early stage of development in Australia. Population-based registries are located in New South Wales Registry and Western Australia, and of these, only the New South Wales Registry is fully functioning. A hospital-based registry is maintained in Victoria. We have a national cancer registry in principle but it will not be functional for many years. Preliminary statistics for New South Wales indicate a cancer pattern similar to Caucasian populations. Some epidemiologic surveys have been undertaken.

Fatal graft-versus-host disease following transfusion of granulocytes from normal donors

A case of fatal graft-versus-host disease was seen in an adult with acute leukaemia, after transfusion of leucocytes from normal donors. This is the first reported case of graft-versus-host disease following transfusion of normal blood-products to a patient with a disease not usually associated with severe immunoincompetence. The number of lymphocytes transfused was no higher than that given when platelet concentrates are prepared from a single donor.

Parameters of temporal recovery of the human auditory evoked potential

Auditory evoked potentials (AEPs) to tone pips at three monopolar scalters were systematically varied: tone intensity (3.0, 1.5 and 0.75 sec), and direction of attention. Interstimulus intervals were computed separately for the 9 different combinations of the three possible first prior intervals (intervals between the test stimulus and the stimulus immediately preceding it) and the three possible second prior intervals (intervals between the stimulus preceding the test stimulus and the stimulus prior to that). Our results show that temporal amplitude recovery of N1 and P2 can be based solely on the first prior interval had not effect on amplitude. Furthermore, they show that it is inadvisable to use combined N1-P2 amplitude measures since the two peaks appear to be governed by separate processes. Recovery for N1 was different from that of P2, N1 showed no intensity effects while P2 did, and N1 and P2 had different topographic distributions. Directing attention to the tones did not affect N1 or P2 amplitudes but caused a highly significant increase in both N1 and P2 latency. Attention to the tones also produced a frontal negative baseline shift following them.

Attention effects on auditory evoked potentials to infrequent events

In two experiments, evoked potentials (EPs) were obtained for three levels of attention, defined by instructions to press a button to, listen to or ignore an infrequent event. In experiment 1, a regular train of standard tone pips was occasionally and randomly interrupted by a tone of different pitch (pitch change) or by the omission of a tone (gap). At the vertex (Cz) a late positive peak (P3) to the infrequent event became larger and later with increased attention, while the earlier negative peak (N1) became later but not larger. In experiment 2, EPs to pitch changes were recorded from Cz, frontal (Fz) and parietal (Pz) locations. All effects obtained in experiment 1 were replicated. The distribution of P3 was different during the different attention conditions.

Evoked potential correlates of signal recognition between and within modalities

Electrical responses evoked by clicks, flashes, changes in noise level, and changes in light level were recorded from the scalps of human subjects set to detect one of the stimuli. An early negative component of the evoked responses reflects selection between sensory modalities, whereas the later positive component reflects a more complex intramodal discrimination.