Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Can Fam Physician ; 37: 1165-9, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-21229023

RESUMO

Sexually active teenagers are at increased risk of developing cervical abnormalities. It is therefore important to screen them with an annual Pap smear. The techniques of this test are reviewed, as are the importance of sexually transmitted diseases in the development of cytologic abnormalities, the pathophysiology of virus-induced changes, and the terminology of reporting.

2.
Hepatology ; 9(4): 621-4, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2925166

RESUMO

Morris hepatoma 44, whose growth is sensitive to thyroid hormones and prolactin, contains specific receptors for these hormones. In the present experiments, male Buffalo rats bearing Morris hepatoma 7787 were studied to determine the effects of several sex steroid hormones. Castration 1 week postimplantation inhibited tumor growth relative to controls (-53%). Replacement with testosterone propionate (1 mg per day s.c. injection) restored tumor growth to control levels, whereas administration of testosterone (2 mg per day s.c. injection) to castrated controls resulted in significant stimulation. Testosterone administered to control animals at a dose of 1 mg per day stimulated tumor growth (62%), whereas 2 mg per day failed to do so. Progesterone (4-pregnon-3,20-dione) at doses of 125 or 250 micrograms per day (Silastic implants) had no effect on tumor growth, whereas 500 micrograms per day stimulated tumor growth relative to controls. Estrogen (17 beta-estradiol) at doses of 6, 12, or 24 micrograms per day (Silastic implants) did not influence tumor growth. Cytoplasmic testosterone receptors have been demonstrated in tumors (2.2 +/- 0.8 fmoles per mg cytoplasm), although specific cytoplasmic estrogen and progesterone receptors could not be identified in this model. In female rats bearing either Morris hepatoma 44, 7787 or 5123-D, testosterone markedly stimulated tumor growth (226, 328 and 58%, respectively, relative to controls). In conclusion, although Morris hepatoma 7787 appears to be androgen (testosterone) dependent and contains cytoplastic androgen receptors, it lacks specific cytoplasmic receptors for estrogen and progesterone and is not influenced by these hormones except at very high doses of progesterone.


Assuntos
Estradiol/farmacologia , Neoplasias Hepáticas Experimentais/patologia , Progesterona/farmacologia , Testosterona/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Masculino , Orquiectomia , Ratos , Células Tumorais Cultivadas
4.
Cancer Res ; 44(7): 2936-41, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6327029

RESUMO

We have demonstrated recently that the local metastatic growth of Morris hepatoma 44 is thyroid dependent ( Mishkin , S., Morris, H. P., Yalovsky , M., and Murthy , P. V. N. Gastroenterology, 77; 547-555, 1979; Mishkin , S. Y., Pollack , R., Morris, H. P., Yalovsky , M., and Mishkin , S. Cancer Res., 41: 3040-3045, 1981) and that exogenous thyroxine (8 micrograms/kg/day) and prolactin (100 micrograms/day) significantly stimulated tumor growth, while growth hormone (100 micrograms/day) failed to do so ( Pollack , R., Mishkin , S. Y., Morris, H. P., and Mishkin , S. Hepatology, 2: 836-842, 1982). In the present study, thyroid ablation (hypothyroidism) and hypophysectomy inhibited tumor growth significantly. These effects were almost totally reversed by administration of exogenous thyroxine to hypothyroid rats. While prolactin or growth hormone or thyroxine alone failed to restore tumor growth in hypophysectomized animals, administration of all three hormones partially but significantly reversed the inhibition of tumor growth. The number and size of pulmonary metastases paralleled local growth in all the above-mentioned conditions. Plasma membrane lactogenic receptors, measured using human growth hormone, were decreased in hypothyroidism and hypophysectomy groups. Binding levels were restored in those groups in which tumor growth was stimulated. In summary, the local and metastatic growth of Morris hepatoma 44 is affected by anterior pituitary hormones. Plasma membrane lactogenic receptors may mediate these effects.


Assuntos
Angiotensina II/farmacologia , Hormônio do Crescimento/farmacologia , Hipofisectomia , Neoplasias Hepáticas Experimentais/fisiopatologia , Neoplasias Pulmonares/secundário , Prolactina/farmacologia , Tiroxina/farmacologia , Animais , Membrana Celular/metabolismo , Feminino , Cinética , Neoplasias Pulmonares/fisiopatologia , Ratos , Ratos Endogâmicos BUF , Receptores de Superfície Celular/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...