Alpha1-antitrypsin deficiency

No Abstrac

Recent Experiences in the Respiratory Unit of the Johannesburg Hospital

The importance of respiratory disease in medicine is emphasized. One hundred and thirtyfive cases were referred to the Respiratory Unit in a 5-month period. These cases 'have been analysed in terms of age, sex and major disease. Fifty-six patients,of whom 47 had intermittent positive pressure respiration, required treatment in an intensive care unit. Twenty-two patients died in the intensive care unit-a mortality rate of 39%. Also discussed and briefly illustrated are problems of intermittent positive pressure respiration, tracheostomy and endotracheal intubation, cardiac arrhythmias, oxygen toxicity, fat embolism and tetanus

Spontaneous flail chest

The flail chest syndrome usually occurs in association with severe, obvious injury. Two  cases are described in which there was no trauma but in which the causative factors were pathological weakening of the thoracic cage due respectively to multiple myeloma  and to chronic renal osteodystrophy associated with steroid therapy

The electrocardiogram in chronic bronchitis and emphysema

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Its all about connections: hubs and invasion in habitat networks

International audienceDuring the early stages of invasion, the interaction between the features of the invaded landscape, notably its spatial structure, and the internal dynamics of an introduced population has a crucial impact on establishment and spread. By approximating introduction areas as networks of patches linked by dispersal, we characterised their spatial structure with specific metrics and tested their impact on two essential steps of the invasion process: establishment and spread. By combining simulations with experimental introductions of Trichogramma chilonis (Hymenoptera: Trichogrammatidae) in artificial laboratory microcosms, we demonstrated that spread was hindered by clusters and accelerated by hubs but was also affected by small-population mechanisms prevalent for invasions, such as Allee effects. Establishment was also affected by demographic mechanisms, in interaction with network metrics. These results highlight the importance of considering the demography of invaders as well as the structure of the invaded area to predict the outcome of invasions