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51.
JORGEN EKSTR
M 《Acta physiologica (Oxford, England)》1975,93(4):525-530
When the function of salivary glands was abolished by applying ligatures to their ducts and the function of one half of the diaphragm muscle was abolished by sectioning of its phrenic nerve, the choline acetyltransferase activity was found to be increased in not duct-ligated glands and in the intact hemidiaphragm 4 weeks later. The increase was not seen within the first week. The increase in activity appears to be particularly manifested in the nerve endings, since it was seen in the hemidiaphragm but not in the phrenic nerve. Increased stream of impulses in the efferent nerves is thought to be the cause of this increase in choline acetyltransferase activity. 相似文献
52.
S. Coppola R. Caroppo E. Frömter 《Pflügers Archiv : European journal of physiology》1994,429(2):203-209
Following the technical approach described in the preceding publication we have investigated if, and how, stimulation of gastric HCl secretion affects the basolateral ion transport properties of oxyntopeptic cells of Rana catesbeiana stomach. To this end microdissected gastric glands were punctured with conventional or H+-sensitive glass microelectrodes and the effects of changing bath ion concentrations on the cell membrane potential (V
b) and cell pH (pHi) were determined. Except for a transient alkalinization, histamine (0.5 mmol/l) did not significantly affect V
b or pHi. The latter averaged 7.18±0.03 (mean±SEM, n=5) under resting conditions (0.1 mmol/l cimetidine) and 7.21±0.07 (n=5) in the presence of histamine. In addition, neither the initial velocity nor the final steady-state value of the cell alkalinization following a 101 reduction of bath Cl– concentration changed in the presence of histamine, and the same holds true for the cell acidification following a 101 reduction of bath HCO3
– concentration. These observations indicate that the basolateral Cl–/HCO3
– exchanger was not stimulated by histamine, and that no other base transporters were activated. By contrast, the V
b response to elevation of bath K
+ concentration decreased, and so did the initial depolarizing V
b response to bath Cl– substitution, while the secondary hyperpolarizing response increased. The latter observations are compatible with the notion that stimulation by histamine reduced a pH-insensitive part of the basolateral K+ conductance and reduced also the basolateral Cl– conductance. 相似文献
53.
Apoptosis in endometrial glandular and stromal cells in women with and without endometriosis 总被引:29,自引:0,他引:29
Dmowski WP Ding J Shen J Rana N Fernandez BB Braun DP 《Human reproduction (Oxford, England)》2001,16(9):1802-1808
BACKGROUND: The aetiology of endometriosis is unknown. Ectopic dissemination of the endometrial cells gives origin to endometriotic lesions, but occurs in women with and without endometriosis. It has been suggested that increased ectopic cell survival facilitates their implantation. The objectives of this study were to evaluate endometrial apoptosis in women with endometriosis according to: (i) cyclic changes, (ii) glandular and stromal contribution, and (iii) stage of the disease. METHODS: The subjects were women undergoing diagnostic laparoscopy and endometrial biopsies for suspected endometriosis. Spontaneous apoptosis was evaluated using TdT-mediated dUTP-biotin nick end-labelling (TUNEL) assay. Apoptotic cells per 10 mm(2) (apoptotic index) in an area of 10-50 mm(2) in 5 microm endometrial tissue sections were counted and location of these cells was recorded. RESULTS: The apoptotic index in glandular epithelium was lower in endometriosis than controls (26.0 +/- 5.5 versus 51.2 +/- 9.7, P = 0.03) but not in the stroma (36.3 +/- 6.4 versus 48.4 +/- 11.3, NS). In controls, apoptosis was highest during the late secretory/menstrual and early proliferative phases and cyclic variability was apparent. In endometriosis, this cyclic variability was lost. There was a trend toward decreased apoptosis with increasing stage of the disease, but the differences lacked statistical significance. CONCLUSIONS: Spontaneous apoptosis is decreased in the endometrial glands in women with endometriosis, especially during late secretory/menstrual and early proliferative phases of the cycle. This may indicate increased viability of endometrial cells shed during menses, facilitating their ectopic survival and implantation. 相似文献
54.
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
55.
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
56.
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
57.
肾上腺肌纤维母细胞瘤 总被引:2,自引:0,他引:2
明家琼 《临床与实验病理学杂志》1998,14(3):259-260,I036
目的:观察肌纤维母细胞瘤形态及免疫组化特点。方法:对1例儿童肾上腺的肌纤维母细胞瘤进行光镜观察和免疫组化染色。结果:HE中瘤细胞呈梭形、不规则形,排列无序,间杂以淋巴细胞等浸润及胶原纤维束;免疫组化显示瘤细胞Vim(+),SMA+(+),CgA(-),EMA(-)。手术彻底切除肿瘤后,患者临床症状消失。结论:肌纤维母细胞瘤是由既具有平滑肌细胞特征,又具有纤维母细胞特征的独立性肿瘤。 相似文献
58.
The triple A or Allgrove syndrome is an autosomal-recessive disease (MIM*231550) characterized by the triad of achalasia, alacrima and adrenocorticotropic hormone (ACTH)-resistant adrenal insufficiency. Associated features of the syndrome are neurological and dermatological abnormalities. Until the discovery of the AAAS gene as the responsible gene in triple A syndrome, the diagnosis was based on characteristic clinical features. Here we present the clinical and molecular genetic data which demonstrated the marked phenotypic variability in three unrelated patients with triple A syndrome. The final diagnosis of triple A syndrome was confirmed by molecular analysis. In one patient with isolated achalasia, the diagnosis of triple A syndrome could only be made on the basis of the molecular genetic analysis of the AAAS gene. We therefore suggest that the diagnosis of triple A syndrome should be considered in patients who exhibit only one or two of the main symptoms (i.e. alacrima, achalasia or adrenal insufficiency). These patients require careful neurological investigation, and mutation analysis of the AAAS gene should be performed. 相似文献
59.
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
60.
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