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101.
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103.
Gutiérrez-Salinas J Miranda-Garduño L Trejo-Izquierdo E Díaz-Muñoz M Vidrio S Morales-González JA Hernández-Muñoz R 《Biochemical pharmacology》1999,58(11):1831-1839
Ethanol metabolism can induce modifications in liver metabolic pathways that are tightly regulated through the availability of cellular energy and through the redox state. Since partial hepatectomy (PH)-induced liver proliferation requires an oversupply of energy for enhanced syntheses of DNA and proteins, the present study was aimed at evaluating the effect of acute ethanol administration on the PH-induced changes in cellular redox and energy potentials. Ethanol (5 g/kg body weight) was administered to control rats and to two-thirds hepatectomized rats. Quantitation of the liver content of lactate, pyruvate, beta-hydroxybutyrate, acetoacetate, and adenine nucleotides led us to estimate the cytosolic and mitochondrial redox potentials and energy parameters. Specific activities in the liver of alcohol-metabolizing enzymes also were measured in these animals. Liver regeneration had no effect on cellular energy availability, but induced a more reduced cytosolic redox state accompanied by an oxidized mitochondrial redox state during the first 48 hr of treatment; the redox state normalized thereafter. Administration of ethanol did not modify energy parameters in PH rats, but this hepatotoxin readily blocked the PH-induced changes in the cellular redox state. In addition, proliferating liver promoted decreases in the activity of alcohol dehydrogenase (ADH) and of cytochrome P4502E1 (CYP2E1); ethanol treatment prevented the PH-induced diminution of ADH activity. In summary, our data suggest that ethanol could minimize the PH-promoted metabolic adjustments mediated by redox reactions, probably leading to an ineffective preparatory event that culminates in compensatory liver growth after PH in the rat. 相似文献
104.
N. Hernández-Mesa M. Antón M. Arza-Marqués R. Aneiros-Riba E. Groning-Roque 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1996,28(1-3):253-258
CARIBRO was founded in response to the United Nations declaration that the 1990s be designated the Decade of the Brain. The Program of Action is:
- Annual meetings;
- Training courses of the Caribbean School of Neurosciences;
- Network scientific programs;
- Fellowship programs; and
- Dissemination of information on neuroscience.
105.
A. Bonnin J. J. Fernández-Ruiz M. Martín F. Rodríguez de Fonseca M. L. Hernández J. A. Ramos 《Journal of neural transmission (Vienna, Austria : 1996)》1993,92(2-3):81-95
Summary In this work, we studied the possible estrogenic modulation of the effects of 9-tetrahydrocannabinol (THC) on mesolimbic dopaminergic activity, by examining the effects of an acute dose of this cannabinoid: (i) during the estrous cycle; (ii) after ovariectomy, chronic estrogen-replacement and tamoxifen (TMX)-induced blockade of estrogenic receptors; and (iii) combined with a single and physiological injection of estradiol to ovariectomized rats. THC significantly decreased the density of D1 dopaminergic receptors and non-significantly increased the L-3,4-dihydroxyphenylacetic acid (DOPAC) content in the limbic forebrain of ovariectomized rats chronically replaced with estrogens. The decrease in D1 receptors was also produced by TMX, whereas the coadministration of both THC and TMX did not lead to a major decrease. In addition to the trend of THC increasing DOPAC content, this cannabinoid was also able to increase the ratio between DOPAC and dopamine, although this last effect only occurred after coadministration of THC and TMX, which had been ineffective administered individually. All these effects were not seen when THC was administered to normal cycling rats during each phase of estrous cycle and to ovariectomized rats without chronic estrogen replacement or only submitted to a single and acute dose of estradiol. This observation might be related to the fact that the density of limbic cannabinoid receptors increased in chronic estrogen-replaced ovariectomized ratsversus normal cycling, ovariectomized or acutely estrogen-treated ovariectomized rats. Interestingly, THC administration in ovariectomized rats was followed by a slight, although significant, increase in tyrosine hydroxylase activity, which was also observed after coadministration of THC with a short-time and acute dose of estradiol. In summary, THC stimulated the presynaptic activity of mesolimbic dopaminergic neurons, but accompanied by a decrease in their postsynaptic sensitivity. These effects did not appear in normal cycling rats being only evident after ovariectomy and chronic estrogen replacement, which might be related to changes in binding characteristics of cannabinoid receptors in this area. Moreover, some of them appeared after TMX-induced blockade of estrogenic cytosolic receptors, which likely suggests the existence of a certain estrogenic modulation of the actions of THC on mesolimbic neurons. On the contrary, coadministration of THC with a single and shortly tested dose of estradiol was always ineffective in modifying THC effects.Presented in abstract form to the Third IBRO World Congress of Neuroscience, Montreal (Canada), August 4–9, 1991 相似文献
106.
L Ramos J Marcos M Illanas M Hernández-Mora F Pérez-Payá J L Picouto P Santana C Chantar 《Radiology》1978,126(2):379-385
Radiological findings in 12 cases of "Mediterranean" lymphoma are analyzed, 4 of which are associated with gammapathy. These findings have not permitted differentiation of this type of lymphoma from those classically described, although there are two signs that strongly suggest this diagnosis: extension of the lesions along wide areas of the small intestine, almost always including the duodenum, and spiculation of the mucosal fold edges, representing massive plasmocyte infiltration of the lamina propria. The principal clinical, immunological, and pathological aspects are described, as well as the radiological differential diagnosis. 相似文献
107.
From acetone extracts of the exudate of the tree BURSERA ARIENSIS, a new bilignan, named ariensin, has been isolated and characterized as (2R,3R)-bis-2.3-(3.4-methylenedioxybenzyl-)-1.4-butanediol diacetate. The structure has been determined from UV, IR, (1)H-NMR and (13)C-NMR data of the natural product, the dibromo derivative and the hydrolysis product. The optical rotation of the latter allowed the determination of the absolute configuration. 相似文献
108.
Pérez Pérez J Richart López A González Enguita C Cabrera Pérez J Bernacer Borja M Vela Navarrete R 《Actas urologicas espa?olas》2000,24(3):275-277
Presentation of one case of hyporreflexic bladder like a first step of neurotoxicity due to Vinca alkaloids. These drugs produces peripheral neuropathies as usual, but in some rare occasions they may affect to the autonomic nervous system with its effects in the bladder producing hyporreflexic. This disease reverts spontaneously after suppressing drugs. 相似文献
109.
Domínguez Domínguez M Reina Ruiz C Blasco Hernández P Espinosa Olmedo J Conde Sánchez JM Vega Toro P García Pérez M 《Actas urologicas espa?olas》2000,24(3):219-222
Contribution of a retrospective series of 16 patients with type II absorptive hypercalciuria over a total of 1.041 patients undergoing metabolic study due to relapsing renal lithiasis. Clinical history of lithiasis, biochemistry prior to treatment and instituted therapy were examined in all cases. Stones composition, radiologic appearance of lithiasis and evolution of biochemical parameters after medical treatment with a mixture of phosphates were also studied. 相似文献
110.
de Diego Rodríguez E Roca Edreira A Martín García B Hernández Rodríguez R Portillo Martín JA Gutiérrez Baños JL Correas Gómez MA del Valle Schaan JI Villanueva Peña A Rado Velázquez MA Torío Sánchez B 《Actas urologicas espa?olas》2000,24(8):685-688
The schwannoma is a tumor resulting from the Schwann cells of neural shwath, being its retroperitoneal localization quite unusual. This tumor is clinically unspecified and in most of the cases it originates symptoms coming from the compression of the close structures when its localization is retroperitoneal. Its diagnosis is quite often fortuitous being confirmed by anatomopathological study afterwards. The treatment is surgical radical exeresis with subsequent followup. We report a new case of this uncommon retroperitoneal pathology in a female patient showing a nonspecific clinic. Two years after the surgery she remains asymptomatic without any radiological evidence of recidive. 相似文献