that bacterial toxins from Serr&ia rnarc&wena and Streptococcus pyogenes are considerably less toxic when adminis tered to normal mice than when given to mice bearing Sarcoma 37 (1, @). A @0-to SO-fold dosage increase of the toxins is required to produce tissue changes and mortality rates in normal mice equiv alent to those produced in tumor-bearing animals. This difference in susceptibility co...

H recent death of A. B. Mitchell (affectionatel) knowil to all old Queenismeni as A. B.") has severed a link wlhich bounid successive generations of medical aduates to Belfast for half a century. Remembered chiefly for his skill as a geon, he rendered conspicuous service to the Belfast School of 'Medicine in fny directions. He was one of the first to Visualise a hospital colony in the unds surr...

Mechanical ventilation is undoubtedly a lifesaving procedure for patients with acute respiratory failure [1]. Unfortunately the procedure is also associated with a number of unwanted side-effects. Firstly, until recently, mechanical ventilation required endotracheal intubation either through a tracheostomy or with a translaryngeal tube, procedures which can carry some risks [2, 3]. Secondly, by...

EDITSHAL and usually, as in the present case, constructional apraxia will be detected with or without ideational apraxia, alexia, or sensory agnosia. Interpretation of Gerstmann's syndrome as an easily demonstrated and memorable pointer to diffuse cerebral damage accords well with this case, where there is no reason to suspect a highly focal lesion. Gerstmann's syndrome does not seem to have be...

he occasional occurrence of chronic intravascu lar hemolysis following cardiac prosthetic sur gery is well documented.1 In this syndrome the pathophysiologic sequence of events has been postulated to occur as follows: turbulence from val vular deformity fragments erythrocytes and induces intravascular hemolysis. If severe, the resulting anemia increases both cardiac output and turbu lence. Long...

w The major difficulty in albino diagnosis is that although foveal hypoplasii seems a consistent feature, it is not uncommon for an albino to have normal fundus pigmentation, normal iris pigmentation and/or no nystagmus. Only a retina-ge.nicula-coni misprojection seems pathognomonic to albinism since all species of albino mammals share this feature. With appropriate stimulus and recording condi...

SHORT COMMUNICATION Colorectal cancer occurs in more than 1.2 million people worldwide every year (1). In principle, the most effective treatment for colorectal cancer is total resection of the tumour with adequate margins. A stoma is formed after surgical resection if necessary. Since various skin diseases can occur around the stoma, appropriate stoma care and management of these lesions, incl...

Recently a number of endogenous host defence molecules with antimicrobial activity have been identified in mammals, invertebrates and amphibians (for reviews see Ganz, Selsted Within this group of anti-microbial agents there are several small peptides (2-4K.) that include the defensins (found predominantly in mammalian phago-cytes), cecropins, diptericins, attacins, apidae-cins, abaecin, royali...

Venous lakes of the lips (VLL) is a common vascular le-sion caused by a focal dilatation of venules, characterized clinically by soft, compressible, dark-blue to violaceous papules, which occurs most often on the lips of elderly patients. A single layer of flattened endothelial cells and a thick wall of fibrous tissue are observed upon histolo-gical examination (1). VLL persists throughout life...

This paper shows how the relationship between two arrays of arti cial neurons representing di erent cortical regions can be learned The algorithm enables each neural network to self organise into a topolo gical map of the domain it represents at the same time as the relation ship between these maps is found Unlike previous methods learning is achieved without a separate training phase the algor...