Hepatitis C virus (HCV) is a causative agent of chronic liver disease leading tocirrhosis, liver failure and hepatocellular carcinoma. The prevalence of HCV is estimated as 3% of the world population and the virus is a major public health problem all over the world. For over 16 years, since HCV had been discovered, studies of the mechanisms of the viral life cycle and virus-host interactions have been hampered by the lack of a cell culture system allowing the virus to be grown in laboratory conditions. However, in recent years some new model systems to study HCV have been developed. The major breakthrough of the last two years was the cell culture system for maintaining the virus in an adapted hepatocyte-derived cell line. This review describes the techniques and applications of most of the in vitrosystems and animal models currently used for working with hepatitis C virus
2
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
A new mathematical model has been proposed to describe the growth of world population - see formula (2). The coefficients of this model have determined by fit measure (3). Applying the regression function (4) one can obtain more exact world population projection on the years 1986-2003 - see tables 1, 2 and 3.
Autor omawia tendencje w rozwoju ludności świata i zaopatrzeniu w żywność. Ukazuje stan niedożywienia i dyskutuje czynniki ograniczające produkcję i zaopatrzenie ludności w żywność; argumentuje potrzebę zmian w modelu spożycia na rzecz większego udziału. produktów pochodzenia roślinnego; podkreśla konieczność poświęcenia nie mniejszej uwagi niż wzrostowi produkcji przechowalnictwu i stratom poprodukcyjnym. Autor ukazuje wpływ procesu urbanizacji i zmian warunków życia na kształtowanie systemów dystrybucji oraz szanse dla produkcji żywności wygodnej.
EN
The author describes trends in increase of world population and food supply. State of undernutrition and limitations in food production and supply, are discussed. Author argues for change in the model of consumption in favour of larger share of foods of plant origin. It is emphasised that food preservation and lower post-harvest losses are as important as the growth of food production,. Analysis of the influence of urbanization and change in living conditions on distribution systems, is done. Good perspectives for convenience foods are foreseen.