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991.
Martin S Lee 《BMJ (Clinical research ed.)》1984,288(6434):1919
992.
Aspiration pneumonia is defined as pulmonary infiltration caused by inhaled material, either solid or liquid, that is inherently toxic or that initiates a toxic response. We present the case of a solitary lung mass of unknown etiology in which cytology of a fine needle aspiration provided a definitive diagnosis of this disorder. 相似文献
993.
One particular kind of structure offers possible explanations, for long-term memory, efficient consolidation of stored information
from the environment, clustering of data strings and multimodal functioning. It is a possible model for pieces of neural structure
and its use offers a uniform method for both studying and constructing an extensive class of mechanisms. 相似文献
994.
995.
B J Hough S E Terblanche R J Naudé W Oelofsen 《Comparative biochemistry and physiology. A, Comparative physiology》1984,77(2):203-206
The aim of this study was to ascertain the effects of training and ACTH administration on the steroidogenic in vitro response in the adrenal cortex of the rat when the tissue was incubated with ACTH. ACTH in vivo treatment resulted in a highly significant increase in the steroidogenic response (P less than 0.001) whereas training as such caused only a slight but insignificant increase in the steroidogenic responsiveness (P greater than 0.05). Training furthermore strongly suppressed the ACTH in vivo induced response (P less than 0.001). ACTH as such revealed the smallest effect on adrenal mass but the biggest effect on the steroidogenic response. It would seem that long term exercise resulted in an overall increase in the mass and size of the adrenal glands by either increasing the size of existing cells or by increasing the number of cells or both. The latter exercise-induced proliferation of adrenal tissue may involve an adaptive mechanism whereby larger total quantities of adrenal tissue of lowered steroidogenic efficiencies (on a mass basis) are produced in order to meet the stress resulting from the training program. 相似文献
996.
Summary By use of a specific antiserum against synthetic ovine corticotropin-releasing factor (CRF) in the peroxidase-antiperoxidase (PAP) immunocytochemical procedure (Vandesande and Dierickx 1976), CRF-like antigenic determinants were demonstrated in the central nervous system of a human fetus, the Wistar rat, the frog Rana ridibunda, and the American cockroach Periplaneta americana. The immunoreactive CRF-producing cells occur mainly in the nucleus paraventricularis of the rat, while in Rana ridibunda these cells occur in the nucleus praeopticus. Immunoreactive CRF-containing fibres were also visualized. Very clear CRF-immunoreactive products were observed in the brain as well as the corpora cardiaca (CC) and corpora allata (CA) of the cockroach Periplaneta americana. ACTH-immunoreactivity was also demonstrated in the brain-CC-CA complex of this insect. Double immunohistochemical staining (Vandesande 1983) also revealed that both the CRFand ACTH-like substances occur in different neurosecretory neurons and nerve fibres. These results suggest that the antigenic determinants of CRF are very similar in vertebrates and insects bespeaking their very long evolutionary history. 相似文献
997.
I V Zverkov A D Dmitriev S P Veselova V A Vinogradov V G Smagin 《Biulleten' eksperimental'no? biologii i meditsiny》1984,97(1):28-31
Immunohistochemistry was used to study the changes in the number of G cells in the antral part of the stomach of rats (40 animals) with cystamine-induced duodenal ulcer treated with beta-endorphine. In the stomach of rats with cystamine-induced ulcer the number of G cells was discovered to be significantly increased, which was removed by an opioid peptide. Naloxone did not block the action of beta-endorphine. Thus, beta-endorphine changes the number of G cells, the drug action being not associated with opiate receptors. 相似文献
998.
S V Litvinov I V Remennik I N Kriukova 《Biulleten' eksperimental'no? biologii i meditsiny》1984,97(5):600-603
Indirect radioimmunoassay and immunoperoxidase studies provided further evidence of human serum reactivity with murine mammary tumor virus (MMTV) structural proteins. Examination of over 400 human sera from breast cancer (BC) patients and controls has shown that the incidence of antibodies which react with MMTV structural proteins was significantly higher in BC patients (50%) than in patients with carcinomas of other organs (3%) or normal women (3%). However, the percentage of subjects immune to MMTV was higher in pregnant women (10%) as compared with normal subjects. All the women with BC of the first clinical stage had antibodies to MMTV. The percentage of immune donors was lower among patients with BC of the later stages (IIa, 90%, IIb, 76%, III, 27%, IV, 0%). Thus, a good agreement has been demonstrated between the first stages of BC and expression of antibodies to MMTV. 相似文献
999.
1000.