Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.

Ex Input:
Abstract: In an institution for the mentally retarded, a total of 13 (2.4%) susceptible employees seroconverted for hepatitis B during 539 person-years. Two of them developed acute hepatitis B; the cost of their medical care and temporary disability was $7,772. Eleven seroconverters had no elevation of serum alanine aminotransferase, and all seroconverters recovered without chronic sequelae. Nine converters acquired antibody to HBsAg alone; three of these had no client contact. Difficulty in identifying nonoccupational causes of hepatitis B infection in the institutional setting often leads to labeling of all seroconversions as occupationally acquired. Hepatitis B vaccine is recommended for client-care personnel.

Ex Output:
Occupational risk of hepatitis B from institutionalized mentally retarded HBsAg carriers: a prospective study.

Ex Input:
Abstract: The glucocorticoid receptor binding capacity of rat thymus cells disappears when the cells are depleted of ATP by anaerobiosis, and rapidly reappears when ATP levels are restored. Loss and recovery of binding capacity occurs even when protein synthesis is suppressed with cycloheximide. In view of this and similar work in other cell systems, we proposed that in cells deprived of ATP the receptor is present in a form--the 'null receptor' form, as we shall call it--that cannot bind hormone. Although many subsequent observations support this idea, no direct evidence has appeared for the existence of the null receptor. We have attempted to detect the null receptor in WEHI-7 mouse thymoma cells with a monoclonal antibody to the glucocorticoid receptor. Here we report that the null receptor is bound in the nuclei of ATP-depleted cells, and is present in amounts comparable to those of receptors in normal cells.

Ex Output:
Glucocorticoid receptors lacking hormone-binding activity are bound in nuclei of ATP-depleted cells.

Ex Input:
Abstract: It is evident that asthma and the other allergic diseases constitute a health problem of international scope. There is a need for well-designed, large-scale, prospective epidemiologic studies designed to define precisely the magnitude of the worldwide problem created by allergic disorders. Most studies to date have been small and have involved special groups rather than the entire population. With the exception of data reported from developing countries, prevalence rates for childhood asthma are noted to be both increasing and higher than adult rates. While exact reasons are not known, the state of development of immune system regulation and hyperreactivity to allergens encountered in early life may play a role. Whether the actual prevalence and incidence of allergic diseases in children are increasing or whether this observation represents a phenomenon resulting from improved diagnostic methods and recognition of these disorders needs to be established. Paradoxically, despite advances in treatment, the severity of asthma and allergic diseases appears to be increasing. Accordingly, it is especially important to search for the factors that lead to the expression of immune and hypersensitivity mechanisms. Differences in rural and urban populations appear to be real and suggest the need to examine the factors of indoor and outdoor environments created by air pollution, crowding, and allergen exposure and the demands made on the immune system by frequency of challenge by respiratory tract infections. Still among the unknowns is the effect on the natural history of allergic disease after changes in urban-rural residences in countries in which helminth infections are not hyper IgE-stimulating factors. The creation of new occupationally related allergens at worksites and the contribution of industrialization to the deterioration of the natural environment needs to be adequately assessed. Whether breast feeding may have an effect on either the prevention or delayed emergence of food allergies in children requires documentation by long-term prospective studies based on objective testing. A possible relationship between respiratory tract infection and the development of asthma is exemplified by clinical observations. The emergence of asthma in infants increases with successive episodes of bronchiolitis; triggering of asthmatic attacks by acute respiratory tract viral infections is a common occurrence, especially during childhood years; and chronic adult onset asthma is often preceded or accompanied by chronic sinusitis or complicated by lower respiratory tract infection.(ABSTRACT TRUNCATED AT 400 WORDS)

Ex Output:
Epidemiologic and socioeconomic aspects of allergic diseases.