Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 28

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  chronic lymphocytic leukemia
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
In chronic lymphocytic leukaemia (CLL) bone marrow trephine biopsy (BMT) is not required for diagnosis but can have a significant prognostic value and can be used for the detection of the minimal residual disease (MRD) and for assessment of the effectiveness of the treatment applied. The aim of the study was to evaluate the morphological changes in bone marrow after treatment with purine nucleoside analogues cladribine and fludarabine. Bone marrow trephine biopsy was taken routinely from 15 patients with CLL. Bone marrow trephine biopsy was performed on every patient before as well as after chemotherapy. The number of cell elements of the marrow (the degree of atrophy), the patterns of bone marrow infiltration, the presence of reticulin and collagen fibres and the disturbances in bone marrow stroma were assessed. The infiltration of bone marrow by neoplastic cells was observed in all the patients before administration of chemotherapy. The infiltration was followed by an increase in the number of reticulin fibres. After the treatment a regression of the reticulin fibres was observed with the lessening of the infiltration. After the treatment the levels of marrow infiltrate were decreased. Increased hypoplasia of the bone marrow was observed after the chemotherapy.
2-Chloro-2'-deoxyadenine (2CldA) is used for treatment of several lymphoid malignancies. Since this drug is incorporated into DNA, we have undertaken studies on base pairing of 2-chloroadenine (2ClA). 2CldA phosphoramidite was synthesized and used for preparation of 25-mer templates with 2ClA located at site 21 from the 3'-end. Kinetic parameters (Km and Vmax) for the incorporation of deoxynucleoside-5'-triphosphates by AMV reverse transcriptase opposite the 2ClA template, as well as for the extension of 2ClA·T pair, were determined. The efficiency (Vmax/Km) of incorporation of dGTP, dCTP, and dATP opposite 2ClA is at least one order of magnitude lower than opposite unmodified A. The efficiency of incorporation of dTTP opposite 2ClA is about 30-fold lower than opposite A and extension of 2ClA·T pair is 3-fold lower than of A·T pair. From the analysis of the parameters of dTTP incorporation we conclude that formation of 2ClA·T pair is thermodynamically, but not kinetically controlled. The difference in binding energy (ΔΔG) between 2ClA·T and A·T pairs in the environment of the polymerase active site is 2 kcal/mol. Our results indicate that the presence of 2ClA in DNA slows down replication, but does not lead to base-substitution mutations.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 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.