Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 4

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

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
In the past few years increased progress in the in vitro maturation (IVM) and fertilization (IVF) of porcine oocytes has occurred. The recovery of oocytes with full developmental competition was possible in the case of improved in vitro culture (IVC) methods. However, there is still a large problem with polispermic embryos produced by IVF. The construction of culture media supplemented with hormones, amino acids and enzymes belongs to the most important factor in the decreasing of the polyspermy rate. These combinations lead to the decreased polyspermy rate and increased efficiency of fertilizations. The microsurgical injection of single spermatozoon into oocytes (ICSI) belongs to one of the most frequently used techniques. This method omits the natural selection of spermatozoa but may lead to the induction of several developmental defects in offspring. In this review the experimental results associated with in vitro techniques used in porcine reproductive biology have been presented.
Neoplastic diseases are a challenge to modern medicine. The understanding of histological, molecular and genetic transformation leading to cancer is essential in establishing methods for earlier diagnosis and better treatment of oral cavity cancer, not only in humans but also in animals – in particular, in dogs and cats, which develop oral cancer spontaneously. There are several methods of cancer modeling that expand research capabilities. The following overview discusses different methods of inducing carcinogenesis in animals and presents animal models used in the study of carcinogenesis. Publications reviewed in the paper discuss markers used in the diagnosis of oral cancer and describe the concept of cancer stem cells.
The development of pig reproductive biotechnology has made it possible to use this species not only as farm animals but also as important models in biomedical research. Systems based on pig embryos from in vitro fertilization (IVF) are used much more frequently, although the quality of these embryos differs from those produced by in vivo fertilization. The most frequent problems in the IVF procedure are disturbances in both nuclear and cytoplasmic oocyte maturation, and the mechanism of polyspermy specific for this species. Although there has been progress in increasing the number of oocytes produced by in vitro maturation processes, the quality of embryos from these oocytes and their developmental competence is still unsatisfactory. It has been suggested that the most important factor in this process is the establishment of optimal conditions for the development and maturation of oocytes. In this review the authors attempt to explain the molecular basis of oocyte maturation, meiosis resumption, and meiotic spindle assembly. The article is also an opportunity to use the knowledge gained to date in order to increase the efficiency of animal breeding, to evaluate the genetic value of oocytes, as well as to improve assisted reproductive techniques (ART).
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.