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991.
992.
Summary Ultrastructural features of muscle spindles were studied in biopsy material from 100 patients suffering from classical rheumatoid arthritis. Thickening of the outer capsule, increased amount of extracellular ground substance within the inner capsule, and marked thickening of the basement membrane of capillary blood vessels supplying the muscle spindles were observed. Chronic inflammatory cells and macrophages were present within the spindles. Changes affecting the intrafusal muscle fibres were also seen. They were manifest as atrophy and degeneration of the intrafusal muscle fibres, absence of the specialised junctional complexes, and of the intercellular bridges, microladders and satellite cells. It is suggested that the changes affecting the intrafusal muscle fibres are probably secondary. Damage to the myelinated nerves was present, while the sensory and motor nerve endings were well preserved.Temporary Research Fellow the Rotterdam Centre for Rheumatic Disease Present address: Division of Pathology, Department of Obstetrics and Gynaecology, University of Chicago, Chicago, Illinois 60637, USA  相似文献   
993.
Salivary thermolytic mechanism (weight of salivary glands, effect of desalivation on water intake and body temperature, grooming activity) as well as escape behaviour and reaction to heat pain were studied in capsaicin-desensitized and control rats exposed to various warm ambient temperatures. Body temperature of the desensitized rats increased more than the controls at all the ambient temperatures studied (32, 34 and 36°C); however, significant differences in the mechanism of salivary cooling were obtained only at 34 and 36°C. Central impairment of saliva spreading in desensitized rats seems evident. Complete surgical desalivation did not increase hyperthermia of control and desensitized animals in warm environments. Therefore other mechanisms, primarily vasodilatatory, must also be involved in the rat's thermolytic normal response. Although desensitized rats did not show a tendency to escape from the warm environment their response to heat pain was normal. In conclusion, it is suggested that heat perception in desensitized animals is impaired; however, the existence of some capsaicin-insensitive thermolytic mechanisms (prone extension of the body) cannot be excluded.Supported by the Scientific Research Council, Ministry of Health, Hungary /4-05-0303-04-2/0/ and MTA-OM-MÉM-EÜM 70.211/79  相似文献   
994.
Résumé Ce travail tente de définir une écho-anatomie du foie normal à partir de neuf plans tomographiques de référence, chacun étant caractérisé par la morphologie de la glande hépatique, par son contenu structural et par son environnement topographique.Les auteurs interprètent l'imagerie échographique directement à partir de l'observation macroscopique de coupes anatomiques correspondantes. Ils indiquent que la corrélation anatomo-échographique est satisfaisante et dégagent quelques indications spécifiques pour chacune des incidences.  相似文献   
995.
Development and growth of primary (methylcholantrene or benzpyrene-induced) sarcomas in adjuvant arthritic rats were investigated and compared with the chemical carcinogenesis in normal healthy animals. When carcinogen and adjuvant were applied in the same time, tumor development and growth rate did not differ significantly from nonarthritic controls. When carcinogen was applied to rats with fully established arthritic disease, development and growth of tumors were significantly enhanced. In the latter case local and systemic adjuvant disease was more severe in tumor-bearing rats. Enhanced chemical carcinogenesis in arthritic rats can be explained by a defective immune responsiveness in the chronic stage of arthritis.  相似文献   
996.
Seven strains of Tettnang virus were isolated in Czechoslovakia: 3 from Ixodes ricinus tick nymphs, males and females, one from Dermacentor reticulatus tick females, one from Aedes cantans mosquitoes and two strains from the brains of Clethrionomys glareolus and Apodemus flavicollis small rodents.  相似文献   
997.
998.
999.
In the present report we describe the preparation of LC-6.2HCl, a soluble derivative of the synthetic bispyrazole LC-6. Because the latter was practically insoluble in aqueous and organic media, experiments which indicated that it had antiallergic activity were confined to in vivo studies following its oral administration. The availability of soluble LC-6.2HCl made it possible to administer the drug i.v. or i.p. Through these routes it exhibited greater antiallergic activity than by the oral route, as judged by lower ID50's and by the achievement of 100% PCA inhibition. The latter result had not previously been attained orally with the base. Furthermore, when injected i.v. or i.p. LC-6.2HCl showed prolonged inhibitory activity, a valuable attribute of the parent compound. The in vivo activity of the soluble salt, which we describe, further establishes the potential therapeutic value of the drug.  相似文献   
1000.
Summary The eye movements produced by constant-speed rotations about an earth-horizontal axis (EHA) are similar in the alert squirrel monkey to those observed in other species. During EHA rotations, there are persistent eye movements, including a nonreversing nystagmus at lower rotation speeds and either a direction-reversing nystagmus or sinusoidal eye movements at higher rotation speeds. Horizontal eye movements are produced by barbecuespit (yaw) rotations, vertical eye movements by head-over-heels (pitch) rotations. The responses can be viewed as composed of a bias component, reflected in the nonreversing nature of the nystagmus, and a cyclic component, reflected in the periodic modulation of slow-phase eye velocity as head position varies. Vestibular-nerve recordings in the barbiturate-anesthetized monkey indicate that neither semicircular-canal nor otolith afferents give rise to a directionally specific dc signal which can account for the bias component. Apparently the appropriate dc signal has to be constructed centrally from a sinusoidal or ac peripheral input. The otolith organs are a likely source of this peripheral input, although contributions from the semicircular canals and from somatosensory receptors must also be considered. Our results suggest that the directional information required to distinguish rotation direction, rather than being contained in the discharge of individual otolith afferents, is encoded across a population of afferents. Possible sources of such information are the phase differences in the sinusoidal responses of otolith afferents differing in their functional polarization vectors.Supported by Grants NS 01330 from the National Institutes of Health and NGR-14-001-225 from the National Aeronautics and Space Administration  相似文献   
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