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排序方式: 共有675条查询结果,搜索用时 8 毫秒
621.
用两种惊厥模型,通过跳台法和避暗法观察了临床常用的几种抗癲痫药抗惊厥作用,以及对学习记忆的影响。结果表明:对抗马桑内酯惊厥,以硝基安定和氯硝基安定效果最好,苯巴比妥及丙戊酸钠次之,酰胺咪嗪和芹菜甲素无效,而苯妥英钠及抗痫灵则能加重惊厥;在电惊厥模型中,以苯妥英钠和苯巴比妥效果最佳,丙戊酸钠及酰胺咪嗪次之,其它药物无效;除芹菜甲素外,其余七种药物均能削弱记忆获得。硝基安定和氯硝基安定可保护马桑内酯惊厥对记忆的损害,而硝基安定能加重电惊厥对记忆的损害。 相似文献
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623.
青花椒化学成分的研究 总被引:26,自引:0,他引:26
自青花椒(Zanthoxylum schinifolium Sieb et Zucc)的果皮中分离出五个化合物。经鉴定化合物Ⅰ为香柑内酯(bergamten),Ⅱ为伞形花内酯(umbelliferone)Ⅲ为茵芋碱(skimmianine),Ⅳ为N-甲基-2-庚基-4-啉酮(N-methyl-2-heptyl-4-quinolone)。Ⅱ,Ⅲ,Ⅳ均为首次从本植物中分出,Ⅳ是从植物中得到的新化合物,命名为青花椒碱(scllinifoline),结晶Ⅴ的结构待定。青花椒碱经药理试验,表明有选择性抑菌作用,对革兰氏阳性菌抑制作用较强。 相似文献
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To evaluate whether increased plasma homocysteine concentrations (hyperhomocysteinemia) are associated with thrombosis of arteriovenous (AV) grafts, we determined plasma homocysteine, plasma and erythrocyte folate, plasma vitamin B12, and vitamin B6 (pyridoxal-5'-phosphate [PLP]) in 48 patients (45 black patients and three white patients) with end-stage renal disease who received hemodialysis. 5,10-Methylenetetrahydrofolate reductase (MTHFR) genotypes were also analyzed. The patients were divided into two groups, including a thrombosis-prone group with frequent graft loss (n = 24) and a control group with prolonged graft survival who were matched by age and duration of dialysis (n = 24). Hyperhomocysteinemia (>15 micromol/L) was found in 42 patients. There were no significant differences in all values, including the concentrations of homocysteine and vitamins between the two groups. Based on plasma folate and PLP concentrations, over 70% of patients appeared to have inadequate folate and/or vitamin B6 nutriture. Plasma homocysteine concentrations showed significant negative correlations with plasma and erythrocyte folate, and plasma vitamin B12 in all patients combined, whereas no significant correlation was found between plasma PLP and homocysteine concentrations. Among 48 patients, the heterozygous mutation (Val/Ala) of MTHFR was found only in three patients, two of whom belonged to the thrombosis-prone group and one to the control group, and there were no individuals with homozygous thermolabile mutation (Val/Val). All three white patients had Ala/Ala genotype, and 3 in 45 black patients (6.7%) were heterozygotes (Val/Ala). 相似文献
626.
GS Saiprasad A Banerjee SL Jadhav PK Sahoo SSL Parashar DR Basannar 《Medical Journal Armed Forces India》2003,59(3):197-201
A cross sectional survey was carried out among the troops located in a large cantonment using the UNAIDS standard survey questionnaire (UN Best Practice Collection) for Behavioural Surveillance Survey (BSS). A total of 556 randomly selected recruits and soldiers were administered the questionnaire. The median age at first sexual encounter was 25 years for service personnel and 18 years for recruits. 5.5% of the recruits and 1.7% of regular soldiers reported having regular sexual partners other than spouse. Among those who had casual sex 46.3% reported using condoms. 52.3% were aware about the two main preventive indicators. Some incorrect beliefs regarding transmission of HIV/AIDS were also present among some of the respondents. The findings have been discussed in relation to previous studies.Key Words: AIDS, Behavioral Surveillance Survey, HIV, Troops 相似文献
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629.
扁果绞股蓝化学成分的研究 总被引:4,自引:0,他引:4
从扁果绞股蓝(Gynostemma compressum X. X. Chen et D. R. Liang)中分离出四个皂甙,经光谱及化学方法鉴定了它们的化学结构,分别命名为扁果绞股蓝皂甙Ⅰ~Ⅳ(gycomoside Ⅰ~Ⅳ),均为新化合物。 相似文献
630.
Simeone JF; Butch RJ; Mueller PR; vanSonnenberg E; Ferrucci JT Jr; Hall DA; Kopans DB; Dawson SL; Wittenberg J; McCarthy K 《Radiology》1985,154(3):763-768
The sonographic appearance of the response of the common hepatic duct to physiologic stimulation by a fatty meal was assessed in 131 patients referred because of right upper quadrant symptoms or abnormal liver chemical studies. In the determination of the presence or absence of biliary obstruction, the sensitivity of the examination was 84%, the accuracy of a positive test was 84%, and the accuracy of a negative test was 93%. This test proved helpful in several circumstances: equivocal duct caliber (6-10 mm); abnormal caliber (6-14 mm) with normal laboratory values; normal caliber duct with abnormal laboratory values; persistent question of cholelithiasis or asymptomatic pancreatic duct dilatation. Measurements of bile duct caliber alone may be insufficient to ascertain the presence of bile duct obstruction and fatty meal stimulation significantly improves diagnostic accuracy. 相似文献