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41.
The value of fine-needle aspiration biopsy in the cytodiagnosis of salivary gland lesions 总被引:1,自引:0,他引:1
Fine-needle aspiration cytology (FNAC) was performed on 195 cases of salivary gland lesions. The smears were technically adequate in 178 cases. Tissue examination was available for subsequent histocytologic correlation in 57 cases. The cytodiagnosis included inflammatory lesions (59) and benign (68) and malignant (51) tumors (total, 119). The accuracy of cytodiagnosis was 87.7% with a sensitivity of 80.9% and a specificity of 94.3%. Exact histologic typing was possible in 61.9% of the malignant tumors. Mucoepidermoid tumors and cellular-atypical pleomorphic adenoma posed difficulties in cytodiagnosis. 相似文献
42.
V. V. Mikhailov M. A. Gordeeva A. G. Rusanova 《Bulletin of experimental biology and medicine》1991,111(3):301-302
Department of Pathological Physiology, N. A. Semashko Moscow Medical Stomatologic Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 3, pp. 246–297, March, 1991. 相似文献
43.
Seeliger F Drögemüller C Tegtmeier P Baumgärtner W Distl O Leeb T 《Journal of comparative pathology》2005,132(4):346-349
A 2-year-old German Holstein bull was identified as a carrier of a mutation within the X-chromosomal ED1 gene, which encodes a TNF-related signalling molecule mainly involved in ectodermal development. The clinicopathological appearance was associated with hypotrichosis, hypodontia, and a reduced number of eccrine glands, in addition to chronic rhinotracheitis and partial squamous metaplasia. Furthermore, for the first time in an ED1-deficient animal, a complete lack of respiratory mucous glands was observed. This suggests that the ED1 gene plays a role in the development of mucous glands, the absence of which resembles a feature of X-linked anhidrotic ectodermal dysplasia (ED1) in human patients. 相似文献
44.
Phosphoinositide kinases were characterized in membrane extracts of rat submandibular gland cells. Both phosphatidylinositol (PI) 4-kinase and phosphatidylinositol-4-phosphate (PI(4)P) 5-kinase phosphorylated endogenous substrates in reactions that were linear for up to 5 min, were activated by Mg2+ and showed maximal activity around neutral pH. PI 4-kinase was stimulated by Triton X-100 at an optimal concentration of 0.22%, but the detergent had an inhibitory effect on PI(4)P 5-kinase. Arachidonic acid (AA), at concentrations greater than 100 M, inhibited the activity of both enzymes in a dose-dependent manner. The inhibitory effect was replicated by other unsaturated fatty acids, but not by a saturated fatty acid of the sn-20 series. The nature of AA inhibition of the kinases was examined in enzyme kinetic studies with exogenous phosphoinositide and adenosine 5-triphosphate (ATP) substrates. Lineweaver-Burk plots of PI 4-kinase activity showed that AA had no effect on the apparent K
m for either PI or ATP, but that the fatty acid significantly reduced V
max (PI) from 331 to 177 pmol.mg–1.min–1 and V
max (ATP) from 173 to 59 pmol.mg–1.min–1. This inhibitory action was consistent for PI(4)P 5-kinase kinetics, where again, AA did not alter apparent K
m values, but lowered V
max for both PI(4)P and ATP by around 50%. Since the combination of a reduced V
max and an unchanged K
m value indicates noncompetitive enzyme inhibition, it is proposed that AA regulates phosphoinositide cycle activity in submandibular gland cells by acting as a noncompetitive inhibitor of PI 4-kinase and PI(4)P 5-kinase. 相似文献
45.
Jürgen Bohl Hans Steinmetz Stephan Störkel 《Virchows Archiv : an international journal of pathology》1991,419(1):51-58
Summary Intracellular fibrillar congophilic inclusions are well known as neurofibrillary tangles in neurons and as Biondi bodies in choroid plexus epithelial cells. Recently similar amyloid-like inclusions in adrenal cortical cells were described (Eriksson and Westermark 1990). This study on 150 adrenal glands confirms these observations. In our material the age-related accumulation of congophilic inclusions starts earlier (in the sixth decade) and reaches a higher incidence (42.7%). We found similar intracellular inclusions in other endocrine organs, for example in the anterior lobe of the pituitary, in the cells of parathyroid glands and in Sertoli cells. The age-related incidence of these fibrillar inclusions in the pituitary was 68%; the co-incidence with interstitial amyloid deposits was 49.5%. Thus the intracellular accumulation of congophilic fibrils in old age is a widespread phenomenon and occurs not only in neurons but also in endocrine cells (adrenal, pituitary and parathyroid glands) and in active secretory cells (choroid plexus and Sertoli cells). 相似文献
46.
The feeding behavior of rats sympathectomized by neonatal administration of guanethidine (GUA) and/or adult adrenal demedullation (MDL) was investigated. GUA treatment tended to decrease body weight gain and food intake, chiefly by decreasing meal size and increasing satiety ratios. It also attenuated the increase in food intake caused by 2-deoxy-D-glucose (2DG; 150, 300, 450 mg/kg, IP) but not by insulin (3, 6, 9 U/kg, IP). MDL altered meal patterns in the same manner as GUA treatment but the effects were of smaller magnitude. It did not influence the response to either glucoprivic challenge. Combined GUA treatment and MDL generally produced additive effects. These results suggest that the major sympathetic influence on feeding is through adrenergic innervation and not circulating catecholamines. The hypothesis that the alteration in feeding patterns produced by ventromedial hypothalamic lesions is due to decreased sympathetic activity was not supported. 相似文献
47.
P Mormède R Dantzer P Montpied R M Bluthé E Laplante M LeMoal 《Physiology & behavior》1984,32(5):723-729
The present experiment investigated changes in pituitary-adrenal activity, prolactin and catecholamine synthesizing enzymes in rats exposed to electric shocks in pairs or individually, in comparison to animals receiving no shock and tested in pairs or alone. Pairs of rats repeatedly exposed to electric shocks displayed a lower activation of the pituitary-adrenal system but a stronger activation of the sympathetic-adrenal medullary system than rats shocked individually. There was no differential release of prolactin according to the social setting in which shock occurred. Social factors by themselves influenced plasma corticosterone levels but not plasma levels of ACTH and prolactin nor catecholamine synthesis. The results are discussed in relation to the postulated beneficial effects of fighting on physiological activation produced by electric shock. 相似文献
48.
V Di Marino M Argème Ch Brunet R Coppens J Bonnoit 《Surgical and radiologic anatomy : SRA》1987,9(1):51-62
Summary The dissection of. 48 cadaveric specimens has been compared with operative findings for a review of the shape, size and site of this gland in the adult. The structure of the thymic compartment and the relations of the thymus, particularly with the vessels of the superior mediastinum and the base of the neck, were studied. The relative positions of the inferior parathyroid glands and the thymus were identified, with respect to the influence of this topography on the surgery of these glands. The arterial suply to the thymus, which is still very abundant in the adult, presupposes a functional organ whose physiologic involution is slow.
Etude macroscopique du thymus de l'adulte
Résumé La dissection de 48 pièces cadavériques, confrontée à des données opératoires, permet de rappeler la forme, la taille et la situation de cette glande chez l'adulte. La constitution de la loge thymique puis les rapports du thymus avec, en particulier, les vaisseaux du médiastin supérieur et la base du cou sont étudiés. Les positions respectives des glandes parathyroïdes inférieures et du thymus avec l'incidence de cette topographie dans la chirurgie de ces glandes, sont précisées. La vascularisation artérielle de la glande, encore très riche chez l'adulte est en faveur d'un organe fonctionnel dont l'involution physiologique est lente.相似文献
49.
Unlike acetylcholine, caffeine was much more effective in releasing catecholamine in the absence of extracellular Ca2+ than in its presence in perfused cat adrenal glands. The intracellular Ca2+ antagonist, TMB-8 (10−4 M), inhibited reversibly the catecholamine secretion evoked by caffeine (40 mM) and that induced by acetylcholine (10−4 M) in the presence of hexamethonium (10−3 M) during perfusion with Ca2+-free Locke solution containing EGTA (10−5 M). These results support our view that muscarinic receptor activation causes catecholamine secretion by mobilizing Ca2+ from an intracellular pool just as caffeine does. 相似文献
50.
The escape efficiency of two closely related species of frogs,Odontophrynus cultripes(2n=22) and the tetraploidO. americanus (4n=44), were compared in a shuttle box and under simulated naturalistic conditions.O. americanus was generally superior toO. cultripes, and females tended to outperform males within both species. The relative inefficiency ofO. cultripes escape behavior was examined in light of the animals' having an elaborate, passive defense mechanism in the form of well-marked venom glands. Escape efficiency was highly variable in both species. Possessing twice the amount of DNA, the tetraploid behavioral variation was paradoxically less than that of the diploid, but compatible with what has been found for morphological characters in other organisms.This research was carried out at the Instituto Butantan with the support of ongoing grants from the Brazilian CNPq, FAPESP, FEDIB, and PNUD while the first author was a visiting professor in the Departamento de Genética Humana, Instituto de Biociências, Universidade de São Paulo, under the auspices of the Programa Multinacional de Genética, Organization of American States. 相似文献