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51.
Dipyridamole and RA-642 inhibit the production of superoxide anion and free radical damage to rat lens. 总被引:1,自引:0,他引:1
J P De la Cruz A Sintas A Moreno J Garcia-Campos F Sanchez de la Cuesta 《Pharmacology & toxicology》1991,69(3):201-204
We studied the effects of dipyridamole and RA-642 on the production of superoxide anions and on oxygen radicals-induced lipid peroxidation in lens tissue homogenates from normal rats and rats given dipyridamole or RA-642 intraperitoneally. Superoxide production was evaluated by phenazine methosulphate (PMS)-induced nitroblue tetrazolium (NBT) reduction and lipid peroxidation by ferrous sulfate and ascorbic acid (FeAs)-induced malondialdehyde (MDA) production. Dipyridamole and RA-642 showed an inhibitory effect on both assays in the experiments with lens tissue homogenates from untreated or treated rats. The extent of inhibition, however, was significantly higher in pyrimidopyrimidinic-treated rats (range of inhibition at different times of incubation was 18% versus 23-57% for dipyridamole and 14% versus 73-80% for RA-642 in the assay of MDA production, and 10% versus 33-37% for dipyridamole and 2.5% versus 11-32% for RA-642 in the assay of NBT reduction). Concentrations of dipyridamole and RA-642 in lens tissue from treated animals could not be determined (less than 0.001 micrograms/mg of tissue). Although both compounds inhibited lipid peroxidation induced by oxygen free radicals, the mechanism of action might include the role of adenosine as a mediator. 相似文献
52.
53.
Anna Spada†‡ Farzin Reza-Elahi†‡ rea Lania†‡ Atanasio Pandiella†† Monique Bassetti†† Nicoletta Bazzoni† Paloma Gil de Alamo† Giovanni Faglia† 《Journal of neuroendocrinology》1991,3(1):51-56
The effect of thyrotrophin-releasing hormone (TRH) on intracellular free Ca2+ concentration, [Ca2+)i, was investigated with the fluorescent dye fura-2 in cell suspensions obtained from 13 human growth hormone-secreting adenomas and 6 adrenocorticotrophin-secreting adenomas. Preoperatively, 9 out of 13 acromegalic patients showed a positive growth hormone response to TRH administration while none of the 6 patients with Cushing's disease had a plasma adrenocorticotrophin increase after TRH injection. In all the growth hormone-secreting adenomas the addition of TRH (100 nM) caused a significant rise in [Ca2+]i (from a resting level of 133±40 (±SD) to a value of 284±119 nM at 100 nM TRH, n = 42; P<0.001). The transient induced by TRH was found to have a dual origin, one due to Ca2+ mobilization from intracellular stores which was maintained in presence of EGTA (3mM) and verapamil (10 μM) and a plateau phase due to Ca2+ influx from the extracellular media. Somatostatin (0.1 μM) lowered both resting [Ca2+]i and TRH-induced transients. The effect of gonadotrophin-releasing hormone on [Ca2+]i was evaluated on cell suspensions obtained from 6 growth hormone-secreting adenomas. Gonadotrophin-releasing hormone (100 nM) caused a marked rise in [Ca2+]i (from 179±25 to 283±15nM) on the cell suspension obtained from the only in vivo responsive adenoma while it was ineffective in the remaining 5. Although TRH was ineffective in modifying plasma adrenocorticotrophin levels in all patients with Cushing's disease, in 5 out of 6 tumors the addition of 100 nM TRH caused a significant rise in [Ca2+]i (from 102.5 ± 36 to 163±66 nM, n = 22; P < 0.005). However, the effect of TRH on [Ca2+]i was significantly lower than that caused by arginine vasopressin, a physiological stimulator of adrenocorticotrophin release ([Ca2+]i values; 145±78 nM at 100 nM TRH versus 300±140 at 10 nM arginine vasopressin, n = 15; P<0.05). Moreover, the effect of arginine vasopressin on [Ca2+]i was detectable at concentrations as low as 0.1 nM while TRH was effective at concentrations higher than 1 nM. By contrast, gonadotrophin-releasing hormone was ineffective in increasing [Ca2]i in all the adrenocorticotrophin-secreting adenomas studied. Collectively, these data indicate that sensitivity to TRH is present in almost all the growth hormone- and adrenocorticotrophin-secreting adenomas independently of the responsiveness of the individual patients to the peptide. 相似文献
54.
55.
Familial 46,XX gonadal dysgenesis 总被引:1,自引:0,他引:1
J A Portuondo J L Neyro J A Benito A de los Rios A Barral 《International journal of fertility》1987,32(1):56-58
Two sisters, ages 18 and 25, presented with primary amenorrhea and underwent clinical, hormonal, cytogenetic, and pathologic evaluation. Both were of normal stature and lacking of somatic stigmata. Both patients had normal 46,XX karyotype on peripheral blood. Streak gonads were seen in both patients and a rather scanty number of primordial follicles was found in one patient. FSH, LH, and urinary estrogens were consistent with streak gonad syndrome. Autosomal recessive inheritance has been suggested in familial aggregates with XX gonadal dysgenesis. 相似文献
56.
Borras Merce; Valdivielso Jose M.; Egido Ramon; Vicente de Vera Pilar; Bordalba Josep Ramon; Fernandez Elvira 《Nephrology, dialysis, transplantation》2006,21(3):789-791
57.
P. H. B. Willemse J. G. Aalders J. Bouma N. H. Mulder R. C. J. Verschueren E. G. E. de Vries D. Th. Sleijfer 《Gynecologic oncology》1987,28(3):268-277
Thirteen patients with a malignant germ cell tumor of the ovary have been treated with a combination of vinblastine, bleomycin, and cisplatin (VBP). In 12 patients a complete remission was reached, which was maintained in 10 of these patients. One patient with large tumor residues and a partial remission became CR after surgery. The tumor recurred in 2 patients after 6 and 27 months. Overall, 11 of these patients are in long-term remission, from 14 to 84 months after the start of treatment. VBP is an effective treatment for malignant germ cell tumors of the ovary, even in patients with large tumor residuals. 相似文献
58.
Heloísio de Rezende Leite Guilherme Silvério de Oliveira Hélio Henrique de Araújo Brito 《American journal of orthodontics and dentofacial orthopedics》2005,128(2):241-251
This case report demonstrates how extracting a maxillary deciduous canine affects the eruption path of a labially displaced ectopically erupting permanent canine. A long-term follow-up is presented, and the biologic mechanisms are discussed. 相似文献
59.
H A Delemarre-van de Waal 《Nederlands tijdschrift voor geneeskunde》1991,135(49):2324-2327
60.
M D Luque de Castro M Valcárcel 《Journal of pharmaceutical and biomedical analysis》1990,8(4):329-336
The different types of instruments used for monitoring pharmaceutical dissolution testing are presented. Their features and the need for automation are critically discussed. The advantages of flow injection analysis in this respect are illustrated by a variety of examples clearly showing its adaptability to the different problems posed by other automatic and non-automatic alternatives. 相似文献