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31.
Ectopic pituitary adenoma (EPA) is rare and, to the authors’ knowledge, its association with peliosis has not yet been described.
The case of a 38-yr-old woman with clinical and biochemical evidence of Cushing’s syndrome is reported. Magnetic resonance
imaging (MRI) disclosed a normal pituitary and a separate mass in the sphenoid sinus. The surgically remove’s hyaline change
in the corticotrophs, indicating exposure to glucocorticoid excess. By histology, the mass in the sphenoid sinus was a congested,
chromophobic, partly basophilic, periodic acid-Schiff (PAS)-positive pituitary adenoma composed of pleomorphic, adrenocorticotropic
hormone (ACTH)-positive, corticotrophs. There was focal immunopositivity for MIB-1 and proliferating cell nuclear antigen
(PCNA). Electron microscopy confirmed the diagnosis of corticotroph adenoma. A striking finding, consistent with the diagnosis
of peliosis, was the presence of multiple large blood-filled spaces lacking an endothelial lining. The capillaries were dilated,
but often appeared empty and the fenestrated endothelium exhibited discontinuities. The cause of peliosis is obscure. It may
be that the venous outflow was impaired in this case leading to capillary dilation, congestion, hyperpermeability, rupture,
and accumulation of blood in extravascular spaces. 相似文献
32.
33.
Mahadevaiah SK; Odorisio T; Elliott DJ; Rattigan A; Szot M; Laval SH; Washburn LL; McCarrey JR; Cattanach BM; Lovell-Badge R; Burgoyne PS 《Human molecular genetics》1998,7(4):715-727
An RNA-binding motif (RBM) gene family has been identified on the human Y
chromosome that maps to the same deletion interval as the 'azoospermia
factor' (AZF). We have identified the homologous gene family (Rbm) on the
mouse Y with a view to investigating the proposal that this gene family
plays a role in spermatogenesis. At least 25 and probably >50 copies of
Rbm are present on the mouse Y chromosome short arm located between Sry and
the centromere. As in the human, a role in spermatogenesis is indicated by
a germ cell-specific pattern of expression in the testis, but there are
distinct differences in the pattern of expression between the two species.
Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are
female due to a position effect resulting in non-expression of Sry ;
sex-reversing such mice with an Sry transgene produces males with a high
incidence of abnormal sperm, making this the third deletion interval on the
mouse Y that affects some aspect of spermatogenesis. Most of the copies of
Rbm map to this deletion interval, and the Yd1males have markedly reduced
Rbm expression, suggesting that RBM deficiency may be responsible for, or
contribute to, the abnormal sperm development. In man, deletion of the
functional copies of RBM is associated with meiotic arrest rather than
sperm anomalies; however, the different effects of deletion are consistent
with the differences in expression between the two species.
相似文献
34.
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36.
G. W. Nuss R. D. Smyth C. H. Breder M. J. Hitchings G. N. Mir N. H. Reavey-Cantwell 《Inflammation research》1976,6(6):735-747
Fenclorac (a,m-dichloro-p-cyclohexylphenylacetic acid, diethylammonium salt) is a potent nonsteroidal anti-inflammatory agent with significant analgesic and antipyretic activity. Fenclorac had an ED50 of 7.9 mg/kg in the carrageenan paw edema assay and had a duration of action of 18–22 hours. Comparative tests in the carrageenan paw edema assay in the rat indicated that the potency of fenclorac was 13 times that of aspirin, 3.4 times phenylbutazone, 3 times ibuprofen and 0.3 times indomethacin. Fenclorac was less potent than indomethacin, but more potent than phenylbutazone or aspirin in treatment of developing or established adjuvant arthritis. The anti-inflammatory effectiveness of fenclorac did not depend upon the integrity of the adrenopituitary axis and was not affected by the route of administration or sex of the test animal. Fenclorac was 77 times more potent than aspirin and more than twice as potent as indomethacin in reducing fever in rats rendered hyperthermic with brewer's yeast. Fenclorac did not affect normal body temperatures. Fenclorac did not interfere with cellular immune mechanisms as measured by its lack of effectiveness in experimental allergic encephalomyelitis. Antinociceptive testing indicated that fenclorac had peripheral but not central analgesic activity. Fenclorac had an acute oral LD50 in rats and mice of 285 and 430 mg/kg, respectively. The acute gastric lesion UD50 for fenclorac was 7 mg/kg in the fasted rat. Studies using51Cr-tagged erythrocytes indicated that fenclorac did not produce significant fecal blood loss in the rat at twice the therapeutic ED50 dose for up to 12 days after dosing. Extensive and prolonged fecal blood loss was observed with a corresponding dose of indomethacin for up to nine days after administration. Comparison of the antiinflammatory pharmacology, Therapeutic Ratio and the data obtained from the51Cr-fecal blood loss studies indicated that fenclorac was well tolerated after acute or subacute administration to the rat. 相似文献
37.
It has now been established that circovirus infection is common in farmed geese, but little is known about the clinicopathological significance of such infections. Ten clinically diseased geese suspected of being infected by circovirus were studied by in situ hybridization using a goose circovirus DNA probe. Circovirus DNA was demonstrated in the bursa of Fabricius (BF), spleen, thymus, bone marrow, liver, kidney, lung and heart, indicating that infection can be multisystemic. In some birds, virus DNA was present in very large quantities, most notably in the BF, liver and small intestine. With the exception of BF and thymus, there were no histological findings that would have suggested the presence of such quantities of circovirus DNA. In view of the very large quantities of virus DNA labelling present in some tissues, and by analogy to porcine circovirus type 2 infection and psittacine beak and feather virus infections, which are known to cause severe disease, and which have similar virus distribution to that found in our geese, it seems probable that the circovirus was important in the disease manifestations shown by the infected geese. 相似文献
38.
39.
Antigenic analysis of Neisseria gonorrhoeae by crossed immunoelectrophoresis. 总被引:12,自引:10,他引:12 下载免费PDF全文
Crossed immunoelectrophoresis was used to study two complex antigenic preparations from Neisseria gonorrhoeae, one of cytoplasmic origin and the other derived by Triton X-100 extraction of isolated washed gonococcal envelopes, with the aim of developing suitable reference antigen-antibody systems that could be subsequently used to investigate the immune response to gonococcal infection and to monitor envelope preparations for cytoplasmic contamination. A number of parameters were investigated to optimized and standardize antigen preparation, e.g., harvesting and washing of gonococci, methods of bacterial disruption, and washing of envelopes. The effects of Triton X-100 concentration, initial total envelope protein concentration, and the composition, pH, and concentration of buffer on cell envelope extractability were studied to obviate the need to concentrate material before use in crossed immunoelectrophoresis. The electroendoosmotic properties of agarose were a major determining factor in resolving envelope antigens. From 25 to 30 immunoprecipitates were revealed in the envelope antigen-antibody system; 75 to 80 were revealed in the cytoplasmic sytem. Envelope immunoprecipitates with reduced nicotinamide adenine dinucleotide and lactate dehydrogenase activities were identified. Crossed immunoelectrophoresis with intermediate gels revealed the presence of antibodies in a preimmune rabbit antiserum pool to a distinctive fact-moving component in both the envelope and cytoplasmic antigen preparations. The intermediate gel technique also demonstrated that extensive washing of envelope preparations with buffer did not remove cytoplasmic ontamination completely. The method provides a much more sensitive means of monitoring the purity of envelope fractions than the use of single enzy,e markers as indexes of such contamination. The use of rabbit antisera raised to formolized gonococci in intermediate gels indicated that both reference antigen-antibody systems were of potential use in screening immune responses to N. gonorrhoeae. 相似文献