Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Tipo de estudo
Intervalo de ano de publicação
1.
Nature ; 602(7898): 585-589, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35197615

RESUMO

Fast radio bursts (FRBs) are flashes of unknown physical origin1. The majority of FRBs have been seen only once, although some are known to generate multiple flashes2,3. Many models invoke magnetically powered neutron stars (magnetars) as the source of the emission4,5. Recently, the discovery6 of another repeater (FRB 20200120E) was announced, in the direction of the nearby galaxy M81, with four potential counterparts at other wavelengths6. Here we report observations that localized the FRB to a globular cluster associated with M81, where it is 2 parsecs away from the optical centre of the cluster. Globular clusters host old stellar populations, challenging FRB models that invoke young magnetars formed in a core-collapse supernova. We propose instead that FRB 20200120E originates from a highly magnetized neutron star formed either through the accretion-induced collapse of a white dwarf, or the merger of compact stars in a binary system7. Compact binaries are efficiently formed inside globular clusters, so a model invoking them could also be responsible for the observed bursts.

2.
Science ; 358(6370): 1579-1583, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29038372

RESUMO

Gravitational waves have been detected from a binary neutron star merger event, GW170817. The detection of electromagnetic radiation from the same source has shown that the merger occurred in the outskirts of the galaxy NGC 4993, at a distance of 40 megaparsecs from Earth. We report the detection of a counterpart radio source that appears 16 days after the event, allowing us to diagnose the energetics and environment of the merger. The observed radio emission can be explained by either a collimated ultrarelativistic jet, viewed off-axis, or a cocoon of mildly relativistic ejecta. Within 100 days of the merger, the radio light curves will enable observers to distinguish between these models, and the angular velocity and geometry of the debris will be directly measurable by very long baseline interferometry.

3.
Ann Rheum Dis ; 46(4): 339-41, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3592792

RESUMO

Two cases of Weber-Christian panniculitis with onset at 7 months and 3 years 6 months are described. Both show evidence of disturbances in immune mechanisms. The family of the first case has a high prevalence of coeliac disease, and the mother of the first patient also suffers from alopecia areata and dermatitis herpetiformis.


Assuntos
Paniculite Nodular não Supurativa/genética , Pré-Escolar , Humanos , Lactente , Masculino , Paniculite Nodular não Supurativa/patologia , Linhagem
4.
J Clin Pathol ; 39(3): 306-12, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2937810

RESUMO

The epithelium of the human fallopian tube (oviduct) and cervix were studied by histological, immunohistological, and ultrastructural methods with a view to establishing the nature of the so called "basal" and "reserve" cells. The results indicated that the "basal" cells of the oviductal epithelia were T lymphocytes, with a predominance of T cytotoxic and suppressor cells. A more heterogeneous inflammatory cell population was present in cervical epithelium, although once again T cytotoxic and suppressor cells were the most numerous subtype. The intraepithelial inflammatory cells were quite distinct from the cells commonly referred to as "reserve" cells (reserve cell hyperplasia), which have epithelial characteristics. The origin of the "reserve" cells is unclear, but they seem to arise within the epithelium. They probably represent an early sign of squamous metaplasia. The lymphoid tissue of fallopian tube and endocervix shows similarities with that of the endometrium and mucosal associated lymphoid tissue in general.


Assuntos
Colo do Útero/citologia , Tubas Uterinas/citologia , Antígenos de Superfície/análise , Colo do Útero/imunologia , Colo do Útero/ultraestrutura , Células Epiteliais , Epitélio/ultraestrutura , Tubas Uterinas/imunologia , Tubas Uterinas/ultraestrutura , Feminino , Antígenos de Histocompatibilidade/análise , Humanos , Microscopia Eletrônica , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/imunologia
5.
Histopathology ; 8(6): 1069-78, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6098547

RESUMO

A case of homologous Müllerian clear cell carcinofibroma occurring in the uterine corpus of a 71-year-old woman is described. The classification, histogenesis and possible biological behaviour of this unique tumour are briefly discussed.


Assuntos
Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Uterinas/patologia , Idoso , Feminino , Humanos , Neoplasias Embrionárias de Células Germinativas/ultraestrutura , Neoplasias Uterinas/ultraestrutura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...