Paper Presented at the All-Union Institute of Experimental Medicine

Types of Perceptual Acts: The object of the present study is perceptual acts executed on a static or slowly changing visual information field.     

Plant physiology,genetics, biotechnology and pathology in the Institute of Experimental Botany of the Czechoslovak Academy of Sciences (1962–1992)

The main scientific results achieved in individual departments of the Institute of Experimental Botany during 30 years of its existence are briefly summarized. They include methods of studying photosynthesis, ontogenetic changes of photosynthetic characteristics, stress factors affecting photosynthetic activities, photosynthesis of transgenic plants and duringin vitro cultivation, roles of auxins and cytokinins in plant growth and development, development and testing of new plant growth regulators, models of organogenesisin vitro, metabolic and mutagenic activities of phenolic substances, hormonal regulation of flowering, activities of promutagens (nitrosamines, 7,12-dimethylbenzanthracene), model systems of genetic damage, repair synthesis and post-replication repair, developmental pollen biology and biotechnology, extracellular nucleolytic activity of pollen, selection of apple scab immune cultivars of apple tree, chemotaxonomy ofFabaceae andAllium species, selection pressures in embryoids, somatic embryogenesis and nuclear genome changes in plant cell and callus cultures, discoveries of new plant viruses, virus spread and persistence in crops, development of polyclonal and monoclonal antibodies, role of oxidative pentosephosphate cycle in biosynthesis of viral RNA, and virus diseases of forest trees.     

Hepatitis A in Estonia (1990-1999)

During recent 10 years (1990-1999) essential changes occurred the epidemiology of viral hepatitis A (VHA) in Estonia: simultaneously with a decreased level of morbidity (morbidity rate per 100,000 of the population was 78.4 in 1990 and 7.7 in 1996, or 1,241 and 112 cases, respectively), a shift in the age structure of patients from children of preschool age to older age groups took place. Everyday contacts were the main established route of VHA transmission in recent years, but in more than 80% of cases the risk factors of the virus transmission remained obscure. During the regional outbreak of VHA in North Estonia in 1998 (937 out of 989 cases registered in the country) a rise in morbidity was observed among young people aged 15-29 years, when a wide spread of parenteral viral hepatitides B and C and drug addiction were registered in this region. During this outbreak VHA was transmitted mainly through everyday contacts. Still the considerable prevalence of injection drug users who practiced the group use of syringes and needles and took drugs from common containers, a sufficiently high level of the mixed forms of the disease (more than 18% of all registered cases of VHA), detected for the first time, make it possible to suggest that the parenteral transmission route could appear among persons belonging to the above mentioned group. Vaccination is regarded as the most effective measure for the prophylaxis of VHA.