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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
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
994.
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
995.
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
996.
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
997.
Jeroen Kool Sebastiaan M van Liempd Huub van Rossum Danny A van Elswijk Hubertus Irth Jan N M Commandeur Nico P E Vermeulen 《Drug metabolism and disposition》2007,35(4):640-648
A high resolution screening (HRS) technology is described, in which gradient high-performance liquid chromatography (HPLC) is connected on-line to three parallel placed bioaffinity detection systems containing mammalian cytochromes P450 (P450s). The three so-called enzyme affinity detection (EAD) systems contained, respectively, liver microsomes from rats induced by beta-naphthoflavone (CYP1A activity), phenobarbital (CYP2B activity), and dexamethasone (CYP3A activity). Each P450-EAD system was optimized for enzyme, substrate, and organic modifier (isopropyl alcohol, methanol, and acetonitrile) in flow injection analysis mode. Characteristic P450 ligands were used to validate the P450-EAD systems. IC(50) values of the ligands were measured and found to be similar to those obtained with conventional microtiter plate reader assays. Detection limits (n = 3; signal-to-noise ratio = 3) of potent inhibitors ranged from 1 to 3 pmol for CYP1A activity, 4 to 17 pmol for CYP2B activity, and 4 to 15 pmol for CYP3A activity. The three optimized P450-EAD systems were subsequently coupled to gradient HPLC and used to screen compound mixtures for individual ligands. Finally, to increase analysis efficiency, a HRS system was constructed in which all three P450-EAD systems were coupled on-line and in parallel to gradient HPLC. The triple parallelized P450-EAD system was shown to enable rapid profiling of individual components in complex mixtures for inhibitory activity to three different P450s. 相似文献
998.
O N Pavlov 《Experimental & clinical gastroenterology》2006,(2):27-30, 126
There was a study of 422 in-patient subjects of the therapeutic profile. Endoscopy enabled to discover mucous coat erosions of the antral part of the stomach associated with Helicobacter pylori and absence of ulcer in the anamnesis in 8.7% of them (more frequently in women). As many as 81% of such patients belonged to patients with the ischemic heart disease. Erosive gastropathy is accompanied by the activity of the chronic inflammation response in the duodenum mucous coat that is most evident in IHD patients. 相似文献
999.
1000.