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Male Wistar rats (2 months old) were maintained on a nutritionally adequate diet, and diazepam was administered at a dose of 10 mg/kg/day. After 24 weeks the effects on the fatty acid composition of plasma and liver phospholipids were studied. Increased levels of palmitic (16:0), palmitoleic (16:1n-7), stearic (18:0), and oleic (18:1n-9) acids were found in plasma phospholipids. In contrast, the levels of docosapentanoic (22:5n-3) and docosahexanoic (22:6n-3; DHA) acids were drastically decreased by diazepam. A significant decrease produced by diazepam was also found in levels of DHA in liver phospholipids. 相似文献
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Morphological and functional changes in pituitary‐thyroid axis following prolonged exposure of female rats to constant light
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Branka Šošić‐Jurjević Nataša Nestorović Nataša Ristić Ivana Medigović Svetlana Savin Verica Milošević 《Journal of morphology》2014,275(10):1161-1172
Light regulates numerous physiological functions and synchronizes them with the environment, in part by adjusting secretion of different hormones. We hypothesized that constant light (CL) would disturb pituitary‐thyroid axis. Our aim was to determine morphological and functional changes in this endocrine system in such extreme conditions and, based on the obtained results, to propose the underlying mechanism(s). Starting from the thirtieth postnatal day, female Wistar rats were exposed to CL (600 lx) for the following 95 days. The controls were maintained under the regular laboratory lighting conditions. After decapitation, pituitaries and thyroids were prepared for further histomorphometric, immunohistochemical, and immunofluorescence examinations. Concentration of thyroid stimulating hormone (TSH), total T4 and T3 (TH) were determined. Thyroid tissue of light‐treated rats was characterized by microfollicular structure. We detected no change in total thyroid volume, localization and accumulation of thyroglobulin, thyroid peroxidase, and sodium‐iodide symporter in the follicular epithelium of CL rats. The volume of follicular epithelium and activation index were increased, while volume of the colloid and serum levels of TH decreased. In the pituitary, the relative intensity of TSH β‐immunofluorescence signal within the cytoplasm of thyrotrophs increased, but their average cell volume and the relative volume density decreased. Serum TSH was unaltered. We conclude that exposure of female rats to CL induced alterations in pituitary‐thyroid axis. Thyroid tissue was characterized by microfollicular structure. Serum TH levels were reduced without accompanying increase in serum TSH. We hypothesize that increased secretion and clearance of TH together with unchanged or even decreased hormonal synthesis, resulted in decreased serum TH levels in CL group. We assume this decrease consequently led to increased synthesis and/or accumulation of pituitary TSH. However, decreased average TSH cell volume and relative volume density, together with unchanged serum TSH, point to additional, negative regulation of thyrotrophs. J. Morphol. 275:1161–1172, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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Total energy production in rabbit reticulocytes amounted to 136·52 ± 6·50μmol ATP h?1ml?1 of reticulocytes: 88·3 per cent was provided by oxidative phosphorylation, whereas only 11·7 per cent by aerobic glycolysis. Na+K+-ATPase accounted for 23 per cent, i.e. 27·65 ± 2·55μmol ATP h?1ml?1 of reticulocytes, in the overall energy consumption in reticulocytes of rabbits. Under basal conditions ATP for Na+K+-ATPase activity was derived exclusively from oxidative phosphorylation. However, when the activity of Na+K+-ATPase was increased due to the stimulation of adenylate cyclase by (?)-isoprenaline, the additional energy required was provided by aerobic glycolysis. These results indicate that two different compartments, one cytosolic and the other mitochondrial, provide energy for Na+K+-ATPase activity in reticulocytes. 相似文献
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Zoran Maksimović Marina Milenković Dragana Vučićević Mihailo Ristić 《Central European Journal of Biology》2008,3(2):149-154
This paper presents the results of a study on chemical composition and antimicrobial activity of Thymus pannonicus All. (Lamiaceae) essential oil from Vojvodina province (north of Serbia). The investigated oil was hydrodistilled from a flowering plant
and analysed by GC and GC-MS. Fifty-three constituents were identified (>97% of total oil), with geranial (41.42%, w/w) and
neral (29.61%, w/w) as the most prominent. The antimicrobial activity of the oil was evaluated using agar disc diffusion and
broth microdilution method against Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Escherichia coli, two strains of Klebsiella pneumoniae and two strains of Candida albicans. The essential oil exhibited antimicrobial activity to varying degrees against all tested strains. The maximum activity of
T. Pannonicus oil was observed against E. coli, S. aureus and both tested strains of C. Albicans (MIC = 50 μ/ml, each). Moderate activity was observed against P. aeruginosa and one of the tested strains of K. Pneumoniae (MIC = 200 μ/ml), while E. faecalis and the other strain of K. Pneumoniae expressed a higher degree of resistance (MIC > 200 μ/ml). This study confirms that essential oil of T. pannonicus possesses remarkable in vitro antimicrobial activity against several medicinally important pathogens. This is attributable to lemon-scented citral, a mixture
of geranial and neral, which has well-documented antimicrobial activity against a range of bacteria and fungi. 相似文献
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