Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 14

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  zmiennosc antygenowa
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Foot-and-mouth disease virus (FMDV) is an important animal pathogen that belongs to the Aphthovirus genus of the Picornaviridae family and infects cattle and other cloven-hoofed animals. Seven serotypes (A, O, C, Asia1, SAT1, SAT2 and SAT3) have been identified serologically, and multiple subtypes occur within each serotype. FMDV enters cells by receptor-mediated endocytosis. By electron microscopy the FMD virion appears to be a round particle with a smooth surface and a diameter of about 25 nm. The FMD viral particle contains a positive-strand RNA genome of about 8500 nucleotides, enclosed within a protein capsid. The virus capsid is made up from 60 copies each of four virus-encoded proteins VP1 to VP4. The FMDV genome is composed of the 5’ non-translated region (5’NTR), the coding region, and the 3’ non-translated region (3’NTR). The genome encodes a single polyprotein, from which the different viral polypeptides are derived by viral proteases. FMDV populations are genetically and anti-genetically heterogeneous. FMDV have very high mutation rates.
Influenza, which affects people and animals, is caused by type A influenza viruses, a member of the Orthomyxoviridae family. The viruses are characterized by a considerable antigen variability. Two kinds of the variability are known: antigenic shift and antigenic drift. Type A viruses appear in populations of birds worldwide. They may be pathogenic for some birds and non-pathogenic for others. Infected wild water fowl, migratory and marine birds which show no clinical signs are the largest natural reservoir for all types of influenza viruses and they are the main source of infection for domestic birds and other animals. The influenza is zoonosis. H5N1 influenza virus strain was initially transmitted directly to humans in Asia in 1997. The virus has subsequently appeared at the end of 2003 in Hong Kong and it has been diffused to several countries of Asia. According to WHO, the total number of affected persons in these countries on December 07, 2005 was 137 of which 70 of them died. In 2005 avian influenza was noticed in Russia, Kazakhstan, Mongolia, Romania and Turkey. In these countries no infections in humans were observed. According to WHO, FAO and OIE the avian influenza appearing in many Asian countries and expanding to the West is a serious threat for human health.
A Polish strain of foot-and-mouth disease virus type О from the laboratory virus collection was used. The virus was propagated in BHK-21 monolayer cells. Total RNA was extracted by the Chomczyński and Sacchi method. A synthesis of cDNA was performed with AMV-reverse transcriptase. The first and second cDNA strands were used as a template for the amplification by PCR of the 672 bp of the VP1 coding sequence. The amplified fragment of cDNA was cloned in the phagemid pBS (+). The first DNA strand expressed in the phage M13K07 was sequenced according to the Sanger method. The nucleotide sequences were compared to the earlier data published. Genetic similarities to the Brasilian strain of FMDV O1 Campos 58 were found.
Bovine respiratory syncytial virus (BRSV) is a virus of the Pneumovirus genus belonging to the subfamily Pneumovirinae of the Paramyxoviridae family. BRSV is one of the main infectious agents causing bovine diseases of the upper and lower respiratory tract, affecting mainly young animals under the age of 9 months. It is responsible for high economic losses in the cattle industry around the world. The most effective and widely used method for limiting costs of infection with BRSV is immunoprophylaxis. Till now, this subject was rarely an object of interest in Polish scientific literature, therefore the aim of this article is to present current information on the types of available vaccines, their efficiency and safety. Additionally, a description of the variability of most immunogenic regions of BRSV and it is influence on the efficiency of the commonly used vaccines is included.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.