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991.
The effect of prenatal exposure to diazepam (over gestational days 13-20) on the release of tritiated norepinephrine [( 3H]NE) from selected brain regions was analyzed to determine mechanisms whereby such exposure could disrupt functioning in specific NE neurons, as previously observed. Pregnant rats were administered diazepam (DZ) once daily at doses of 1.0, 2.5 or 10.0 mg/kg and the offspring studied as adults at 70-90 days of age and during development at 14, 21, 35 and 56 days of age. Release of [3H]NE was measured during in vitro incubation using 25 mM potassium as the depolarizing stimulus. As noted previously, prenatal exposure to DZ induced an effect only on NE neurons innervating the hypothalamus, sparing the NE innervation to the hippocampus and cerebellum. Prenatal exposure to DZ had no effect on the depolarized release of [3H]NE in the hypothalamus until after 35 days of age, a developmental pattern previously observed with respect to endogenous NE levels. In adult rat offspring, however, the depolarization-induced release of [3H]NE from the hypothalamus decreased 28%, 32% and 64% (relative to uninjected control values) in animals prenatally exposed to DZ at 1.0, 2.5 or 10 mg/kg/day respectively. Concurrent exposure of the pregnant dam to benzodiazepine antagonists (Ro 15-1788 or ethyl-beta-carboline-3-carboxylate) prevented the effects of DZ (2.5 mg/kg/day) on [3H]NE release, demonstrating again the importance of the benzodiazepine binding site to the effects induced by the early DZ exposure. The initial accumulation of the [3H]NE was not altered by the prenatal exposure.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
Three cases are presented, in which an anomalous tendon slip between the extensor carpi ulnaris tendon and the extensor apparatus of the fifth finger was found. One of the patients was a violinist, who had serious impairment of the left wrist joint and the small finger due to the anomaly. The symptoms disappeared after excision. 相似文献
993.
994.
995.
996.
Radionuclide thyroid imaging was performed in 872 consecutive patients with hyperthyroidism. Of these, 84% were found to have diffuse toxic hyperplasia (Graves' disease), while 12% had autonomously functioning nodules (Plummer's disease), 3% had Graves' disease developing in a multinodular gland, and in the remaining 1%, either a clear diagnosis could not be established or the hyperthyroidism was due to thyroiditis or the Jod-Basedow phenomenon. It was found that a thyroid scan seldom provides additional diagnostic information in patients with Graves' disease when a diffuse goitre is present. However, if patients are to be treated with radioiodine (131I), thyroid imaging with tracer quantitation can replace a 24-h 131I uptake measurement, this having the advantages that the patients are required to attend only once, and that the gland size can be measured. In addition, visual confirmation of tracer uptake by the thyroid is obtained and patients with thyroiditis will not receive inappropriate therapy. When single or multiple thyroid nodules are palpated, a thyroid scan is crucial in establishing an accurate diagnosis, as it is not otherwise possible to differentiate between Plummer's disease and Graves' disease developing in a multinodular gland. Indeed, in 20 of our 63 patients (32%) with single autonomously functioning nodules, the initial clinical assessment had been incorrect. 相似文献
997.
998.
Repeated administration of a large dose of methamphetamine (MA) (25 mg/kg, i.p. twice daily for 4 days) to mice enhanced locomotor activity and decreased stereotyped behavior following a subsequent injection of MA. Simultaneous determinations of catecholamines revealed a depletion of brain dopamine. The moderate doses of haloperidol significantly enhanced MA-induced locomotor activity in mice. A significant enhancement of MA-induced locomotor activity was observed in the rats pretreated with 6-hydroxydopamine into the striatum, and this effect correlated negatively with the striatal dopamine level. These results suggest that hypofunction of striatal dopaminergic neuron systems induced by repeated administration of MA may be one of possible mechanisms of the enhancement of MA-induced locomotor activity due to the decrease of stereotyped behavior. 相似文献
999.
The investigation of AUSTROLIABUM CANDIDUM afforded, in addition to several known sesquiterpene lactones, four new ones, including three germacranolides with an ether bridge, as well as an unusual glucoside. The structures were elucidated by spectroscopic methods. 相似文献
1000.
L. N. Grushevskaya B. M. Pyatin O. B. Stepanenko N. I. Avdyunina V. P. Lezina V. I. Prokof’eva 《Pharmaceutical Chemistry Journal》2007,41(8):440-443
Cardiocyclide, a new Russian class III antiarrhythmic agent, was developed at the State V. V. Zakusov Science Research Institute
Pharmacology, Russian Academy of Medical Sciences. The aims of the present work were to study the physicochemical properties
of the hydrochloride salt of this agent (N1-(3-diethylaminopropyl)-N1-(p-nitrobenzoyl)aminoacetic acid N,N-dicyclohexylamide HCl) and to develop an analytical method for this compound. IR, 1H NMR, and UV spectra were obtained for cardiocyclide; its solubility was studied; its melting temperature, weight loss on
drying and the transparency, color, and pH of its solutions were determined. The purity of material containing compound I
was determined by thin-layer chromatography; quantitative cardiocyclide contents were estimated by non-aqueous titration.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 8, pp. 42–45, August, 2007. 相似文献