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21.
Dopaminergic neurotransmission is involved in several brain functions including spatial cognition. In the present study we examine the effects of systemic administration of D1-like receptor antagonist SCH23390 and D2-like receptor antagonist sulpiride on the acquisition of the Morris water maze task. We used visible versus hidden platform versions of the MWM in order to distinguish between the effects of the drugs on the procedural versus cognitive aspects of the task. SCH23390 was found to prolong escape latencies to the visible platform at a higher dose (0.05mg/kg), whilst the lower dose (0.02mg/kg) left both procedural and cognitive functions almost unchanged. SCH23390 was also found to reduce swimming speed. Sulpiride did not affect the visible platform learning at any of three doses studied (30, 60 and 100mg/kg); the highest dose of sulpiride (100mg/kg) impaired place navigation to the hidden platform, without affecting the swim speed. The results of the present study show a difference in the involvement of D1-like and D2-like receptors in the MWM acquisition. 相似文献
22.
OBJECTIVES: The study objectives were: (a) to evaluate knowledge about osteoporosis and to identify its correlates among women > or =40 years of age attending outpatient centers; (b) to compare the level of knowledge between women already receiving treatment for osteoporosis and first-time attendees. METHODS: A cross-sectional survey was conducted with women recruited from nine outpatient centres in the Czech Republic. The women were divided into two subgroups: patients who have already been diagnosed with osteoporosis (osteopenia) and who are receiving treatment for the disease (OS group); first-time attendees who have been referred for the assessment of osteoporosis (comparison group). The patient's knowledge of osteoporosis was assessed using the Osteoporosis Questionnaire (OPQ) developed by Pande et al. [Pande KC, Takats D, Kanis JA, Edwards V, Slade P, McCloskey EV. Development of a questionnaire (OPQ) to assess patient's knowledge about osteoporosis. Maturitas 2000;37:75-81]. RESULTS: A total of 474 women (median age 63 years) were studied (306 in the OS group, 168 in the comparison group). Knowledge scores based on OPQ (median) were 7 and 6 points in the OS and comparison groups, respectively. When adjusted for age, the statistics showed better knowledge patients in the OS group (P=0.019). In both the OS and comparison groups, knowledge was found to be correlated positively with education (P<0.001) and experience of hormone replacement therapy (HRT) (P<0.001) and negatively with age (P<0.001). Knowledge was higher among women with better health status in the OS group. CONCLUSION: Knowledge about osteoporosis among Czech women aged > or =40 years and attending outpatient centers is relatively poor. To improve it, special attention should be paid to elderly women, those who have not used HRT, poorly educated women and those treated with several drugs. 相似文献
23.
A rare sepsis-like hypersensitivity reaction has been observed in persons with human immunodeficiency virus (HIV) after exposure to trimethoprim-sulfamethoxazole. This reaction most commonly occurs on rechallenge with the drug and is manifested by a syndrome resembling bacterial sepsis. The mechanism of this unusual reaction remains unclear. We describe the first case in which this severe hypersensitivity reaction was the initial manifestation of HIV. 相似文献
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Smejkal K Chudík S Kloucek P Marek R Cvacka J Urbanová M Julínek O Kokoska L Slapetová T Holubová P Zima A Dvorská M 《Journal of natural products》2008,71(4):706-709
Eight C-6-geranylflavonoids ( 1- 8) were isolated from an ethanol extract of Paulownia tomentosa fruits. Tomentodiplacone ( 1), 3'- O-methyl-5'-hydroxydiplacone ( 2), 3'- O-methyl-5'- O-methyldiplacone ( 3), and tomentodiplacone B ( 4) were obtained as new compounds, and 3'- O-methyldiplacol ( 5) was isolated for the first time from a natural source. The structures of these new compounds were determined by using mass spectrometry (including HRMS) and 1D and 2D NMR spectroscopy, and the absolute configurations of the compounds were determined by circular dichroism. The antibacterial activities of 1- 8 against seven bacteria and yeast were evaluated. 相似文献
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Plasma prorenin in first-trimester pregnancy: relationship to changes in human chorionic gonadotropin 总被引:2,自引:0,他引:2
J E Sealey D McCord P A Taufield K A Ales M L Druzin S A Atlas J H Laragh 《American journal of obstetrics and gynecology》1985,153(5):514-519
Prorenin and human chorionic gonadotropin are both synthesized in chorionic cells. The relationship of changes in maternal plasma prorenin to changes in human chorionic gonadotropin were therefore evaluated during the first trimester. In samples submitted to the routine chemistry laboratory for detection of pregnancy a positive relationship was observed between prorenin and beta human chorionic gonadotropin during the 5 weeks following conception. Subsequently human chorionic gonadotropin continued to rise but prorenin had reached a plateau. Serial studies in one subject demonstrated that prorenin had increased to 65% of maximum by the thirteenth day following conception whereas human chorionic gonadotropin had risen to only 0.2% of maximum. By 3 to 5 days post partum, beta human chorionic gonadotropin had fallen by 98% but prorenin had fallen by only 50%. The early rise in prorenin following conception and the relatively slow fall post partum suggest that pregnancy-related changes in maternal plasma prorenin are of maternal, not fetal, origin. 相似文献
29.
Multiple subpial transections: outcome and complications in 20 patients who did not undergo resection 总被引:7,自引:0,他引:7
OBJECT: The authors describe patient characteristics, surgical methods, complications, and outcome over time in a cohort of patients who underwent multiple subpial transection (MST) without concomitant cortical resection. METHODS: Twenty consecutive patients in whom drug-resistant epilepsy had been diagnosed a mean of 16 +/- 9 years earlier (mean +/- standard deviation [SD]) were treated with MST without cortical resection. The mean follow-up period was 49.3 +/- 18.3 months (mean +/- SD, median 58 months). At 12 months of follow up, two of the 20 patients were Engel Class I, one was Class II, six were Class III, and 11 were Class IV. At latest follow up, one patient was Engel Class I, one was Class II, seven were Class III, and 11 were Class IV. According to an alternative five-tiered classification system, two outcomes were excellent, seven were good, one was fair, nine were poor, and one was worse. Outcome was found to be better in patients with no lesions observed on magnetic resonance (MR) imaging, and worse in those with large MST areas. Outcome had a tendency to change (this occurred in 13 of 20 cases). Five patients (25%) improved and seven (35%) deteriorated in Engel outcome class, and in one (5%) both developments occurred over time. Most outcome class changes occurred before the end of the 2nd year (nine), and four were observed in the 5th year. There where seven transient neurological deficits and four surgical complications. There was no permanent significant morbidity, and there were no deaths. CONCLUSIONS: Forty-five percent of patients achieved a worthwhile improvement after pure MST, if Engel outcome Class III is deemed a worthwhile improvement. The alternative five-tiered classification resulted in 50% with worthwhile improvement (excellent, good, or fair outcome), 45% with poor, and 5% with worse outcome. Lesions that are detectable on MR imaging, and large MST areas are predictive of worse results. Significant intraoperative problems may arise, but this happens infrequently. There is a notable rate of transient morbidity but the rate of permanent morbidity is not significant. 相似文献
30.
Dithymoquinone, thymohydroquinone, thymol and thymoquinone, compounds derived from N. sativa seeds, were investigated for their in vitro anti-inflammatory activities using cyclooxygenase-1 (COX-1) and -2 (COX-2) assays. Our results show that all substances tested possess significant inhibitory activity against at least one COX form at concentrations comparable to the active one of indomethacin. Thymol was the most active against COX-1 with an IC (50) value of 0.2 microM while thymohydroquinone and thymoquinone exhibited the strongest inhibitory effect on COX-2 with IC (50) values of 0.1 and 0.3 microM, respectively. Moreover, dithymoquinone and thymoquinone showed a limited COX-2-specific inhibition. We conclude that dithymoquinone, thymohydroquinone, thymol and thymoquinone can participate in the general anti-inflammatory activity of N. sativa and suggest that these agents should be further studied for possible use as non-steroidal anti-inflammatory drugs. 相似文献