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101.
102.
Teresa Sagalés Victor Gimeno M. Dolores de la Calzada Francesc Casellas M. Dolors Macià M. Villar Soriano 《Brain topography》1990,2(3):221-228
Summary Topographical analysis of cerebral electrical activity was performed in 44 patients with hepatic encephalopathy. These patients were classified in 5 groups according to clinical criteria. Eight healthy subjects were used as a control group. All were studied in an awake, eyes closed, condition and some [Control Group (CG), Group 0 (G0), Group 1 (G1) and Group 2 (G2)] also in an awake, eyes open, condition. The awake, eyes closed, maps showed marked differences in the power spectral density (PSD) of the different bands, when comparing normal subjects with patients with several degrees of hepatic encephalopathy. These differences were related to the degree of clinical involvement, mainly in the alpha and delta PSD bands. The combination of a decreased alpha PSD, increased delta PSD, and decreased mean dominant frequency (MDF) allowed a clear discrimination between the different clinical groups. The differences observed between awake, eyes closed, and awake, eyes open, conditions were especially helpful to discriminate between CG subjects and G0, G1 and G2 patients. 相似文献
103.
利用光镜、电镜、免疫组化和形态学定量技术动态研究维生素A对大鼠四氯化碳肝纤维化的抑制作用。结果表明,维生素A可减少四氯化碳中毒大鼠肝内纤维连接蛋白和Ⅰ、Ⅲ型胶原沉积,抑制贮脂细胞向成纤维细胞转化,并可明显地减轻肝纤维化程度。本文还对维生素A抑制肝纤维化的机理及意义作了初步探讨。 相似文献
104.
W. Robert Anderson 《Ultrastructural pathology》1990,14(3):221-232
The sequential stages of bronchopulmonary dysplasia occurring in 18 infants after intensive respiratory therapy supplemented by oxygen in high concentrations were studied by correlative light, scanning, and transmission electron microscopy. Infant survival ranged from 3 to 225 days. The earliest stage was an exudative reaction with a predominance of hyaline membranes. This merged with a subacute reparative response that was replaced by a chronic fibroproliferative stage in infants of longest survival; this stage was complicated by pulmonary fibrosis and emphysema. Correlative scanning and transmission electron microscopy demonstrated that type 2 pneumocytes contributed significantly to the reparative fibroproliferative response by organization of hyaline membranes and reepithelialization of damaged septal walls. 相似文献
105.
Units which are activated by ascending impulses from the liver within the nucleus of the solitary tract (NTS) were identified by electrical stimulation delivered to the hepatic branch of the vagus. Responses of descending units were eliminated by a collision test. The units which showed decreased firing rates during portal infusion of isotonic glucose solution were also glucose-sensitive so that they showed decreased firing rates during topical application of glucose by means of micro-electro-osmotic techniques. It is concluded that glucose-sensitive neurons exist within the NTS and also that they are functionally linked with hepatoportal glucose-sensitive afferent units. 相似文献
106.
107.
YESIM TUNCOK SEBNEM APAYDIN SULE KALKAN MEHMET ATES & HULYA GUVEN 《International journal of experimental pathology》1996,77(5):207-212
The goal of this study was to compare the effects of glucagon and amrinone on mean arterial pressure (MAP) and heart rate, when used alone and in combination, in an anaesthetized rat model of verapamil toxicity. Rats were anaesthetized and the carotid artery was cannulated for MAP and heart rate measurements. Jugular and femoral veins were cannulated for drug administration. After verapamil infusion (15 mg/kg/h), control animals were given normal saline solution and the other groups received amrinone (0.1 or 0.2 mg/kg/min), glucagon (0.3 mg/kg bolus followed by 0.1 or 0.2 mg/kg/min infusion), glucagon plus amrinone (0.1 mg/kg/min and 0.1 mg/kg/min respectively) or glucagon plus amrinone (0.2 mg/kg/min and 0.1 mg/kg/min respectively). Glucagon (0.2 mg/kg/min) significantly increased MAP when compared to the control group ( P < 0.01). The combination of glucagon and amrinone did not produce a synergistic effect for the recovery of MAP. Furthermore, this combination masked the positive effects of glucagon (0.2 mg/kg/min) on MAP.Glucagon (0.2 mg/kg/min) increased the heart rates compared with those of the control group ( P < 0.05). Additionally, amrinone (0.1 mg/kg/min) plus glucagon (0.1 mg/kg/min) increased the heart rates ( P < 0.05). Finally, glucagon dose dependently recovered MAP. While amrinone depressed MAP in combination with glucagon, it did not alter the positive chronotropic effect of high dose glucagon. 相似文献
108.
Haseeb Khan Ahmad Saleh Al Deeb Khalaf Al Moutaery Mohammad Tariq 《Experimental and toxicologic pathology》2003,55(2-3):181-186
A direct association between aging and drug-induced dyskinesia has been reported by several investigators. Iminiodipropionitrile (IDPN), a prototype nitrile compound produces a motor syndrome in rodents, which resembles neuroleptic drug induced dyskinesia. In this investigation attempt has been made to study the effect of age on IDPN induced vestibular hair cell degeneration and resulting dyskinetic syndrome. Male Wistar rats aged 3, 6 and 12 weeks received IDPN in the doses of 0, 200 and 400 mg/kg, intraperitoneally for 3 consecutive days. IDPN-induced dyskinesia was assessed using a behavioral testing battery on days 3, 4, 5, 6, 7, 14, 21 and 28. The rats were sacrificed on day 28; temporal bones were excised for vestibular histopathology and sera were collected for measuring the indices of oxidative stress (glutathione and conjugated dienes). IDPN in the dose of 200 mg/kg produced dyskinesia in 12 weeks old rats, but failed to do so in 3 and 6 weeks old rats. The high dose of IDPN (400 mg/kg) caused dyskinesia in all age groups, however, its onset and severity were age-dependent. Older rats showed an early onset and significantly high incidence of dyskinesia as compared to younger rats. The susceptibility of rats to IDPN-induced behavioral deficits was proportional to oxidative stress and degeneration of sensory hair cells in the crista ampullaris. 相似文献
109.
The liver is a major site for synthesis and catabolism of plasma proteins. Albumin has various binding sites for anionic drugs,
1acid glycoprotein possesses a single binding site for cationic drugs. In spite of extensive protein binding, the liver can efficiently remove drags from the circulation. Intrahepatic dissociation of the drag-protein complex may involve dissociation-limited debinding under non-equilibrium conditions or surface interaction-facilitated dissociation phenomena. During liver or renal disease and acute-phase conditions plasma protein binding of drugs may be affected. Changes in the unbound drag fraction do not always result in proportional changes in clearance or distribution volume. Potential changes in the unbound concentration in steady-state as well as the fluctuations in total plasma levels depend on the extent of protein binding of a drug, the relative change in the unbound drug fraction, type of clearance, the size of the distribution volume, route of administration as well as concomitant changes in intrinsic (cellular) clearance function. Optimization of dosage regimens for certain drags and interpretation of liver function tests with diagnostic dyes may largely benefit from determination of the unbound rather than the total concentration of the drags involved.Part of this work was supported by Grant 900-521-078 from MEDICON, which is subsidized by The Netherlands' Organization of Pure Research. 相似文献
110.
Selected testicular enzymes as biochemical markers for procarbazine-induced testicular toxicity 总被引:1,自引:0,他引:1
Single doses of procarbazine (MIH) were injected IP at 0, 50, 100, 200, and 400 mg/kg body weight to CD-1 male mice. Activities of hyaluronidase, lactate dehydrogenase isoenzyme-X, and the dehydrogenases of sorbitol, -glycerophosphate, glucose-6-phosphate, malate, isocitrate, and glyceraldehyde-3-phosphate in the testes of the mice were determined and correlated with changes in spermatogenic cell types in seminiferous tubules. All enzyme activities were higher than controls or remained unchanged on days 10–20 after drug treatment. Activities of hyaluronidase, sorbitol dehydrogenase, and lactate dehydrogenase isoenzyme-X decreased significantly to below normal levels on day 30 after drug treatment for all doses, whereas those of the other five dehydrogenases remained significantly higher than controls. All enzyme activities approached control levels with the concomitant recovery of spermatogenesis by day 60 after drug treatment. Histological examination of seminiferous tubules revealed that premeiotic spermatocytes were significantly reduced on days 10–20 but reappeared on day 30 after MIH treatment (400 mg/kg). The postmeiotic spermatogenic cells were unaffected at the time of MIH treatment, but had disappeared completely on day 30 after drug treatment. MIH, at the highest dosage, selectively destroyed spermatogonia and premeiotic spermatocytes; however spermatozoa and elongated spermatides were unaffected. This study demonstrated that the cytotoxic effect of MIH on spermatogenesis could be evaluated via changes in testicular enzyme activities. The present studies demonstrated that hyaluronidase, sorbitol dehydrogenase, and lactate dehydrogenase isoenzyme-X could serve as useful biochemical markers for assessing testicular toxicity induced by drugs and chemicals. 相似文献