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31.
The GABA-B agonist baclofen reduces drug self-administration in rats and has shown promise clinically in the treatment of substance abuse. Baclofen generally does not reduce food intake in non-binge feeding protocols. In this study, baclofen was tested in a fat-binge protocol. Thirty male rats were divided into three groups (B: binge; FM: fat-matched; C: chow). B received a bowl of vegetable shortening for 2 h on Monday, Wednesday, and Friday (MWF) and continuous access to powdered chow (regular chow) in all phases. FM had continuous access to a regular chow+shortening mixture (FM chow) that provided the same proportion of shortening and regular chow that the B rats consumed in all phases. In addition, FM had the following: phase 1: no separate bowl of shortening; phase 2: 2-h MWF access to a separate bowl of shortening; phase 3, daily 2-h access to a separate bowl of shortening; C rats had continuous access to the regular chow in all phases. In addition, C had the following: phase 1: no separate bowl of shortening; phase 2: 2-h MWF access to a separate bowl of shortening; in phase 3, daily 2-h access to a separate bowl of shortening. Baclofen (1.0, 1.8 mg/kg, i.p.) reduced shortening intake regardless of access condition. Baclofen had no effect on, or stimulated, FM and regular chow intake. These results demonstrate that baclofen can reduce fat intake in rats under binge-type conditions. Furthermore, these results indicate that bingeing, as modeled in our protocol, is different from other forms of food intake and may share similarities with substance abuse.  相似文献   
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固相萃取GC-FID和GC-MS分析血浆中碱性药物   总被引:5,自引:0,他引:5  
邱丰和  刘力  罗毅  刘峰  卢涌泉 《药学学报》1996,31(4):296-299
报道了用X-5固相萃取分离、毛细管GC-FID和GC-MS定性定量分析人血浆中34种碱性药物的方法。在优化的提取条件下,大部分药物的最低检测浓度在0.5~2.0μg·ml-1之间,线性范围、定量精密度等满足临床中毒分析的要求。  相似文献   
34.
刺南蛇藤倍半萜的研究   总被引:1,自引:0,他引:1  
王明安  刘军  陈馥衡 《药学学报》1997,32(5):368-372
从刺南蛇藤(Celastrus flagelaris Rupr.)种子油中分离到八个β-二氢沉香呋喃倍半萜,经红外、紫外、质谱及核磁共振谱确定它们的结构是1α-乙酰氧基-2α,9β-二肉桂酰氧基-β-二氢沉香呋喃(1),1α,6β,13-三乙酰氧基-9β-苯甲酰氧基-β-二氢沉香呋喃-(2),triptogelinG-1(3),1α,6β-二乙酰氧基-9β-苯甲酰氧基-β-二氢沉香呋喃(4),triptogelinF-2(5),1α,2α-二乙酰氧基-9β-肉桂酰氧基-β-二氢沉香呋喃(6),celaforlinB-3(7),1α,6β-二乙酰氧基-8α-肉桂酰氧基-9α-苯酰氧基-β-二氢沉香呋喃(8)。其中1是新化合物,命名为celastrine B。  相似文献   
35.
36.
目的测定甘肃产五加中剌五加苷B、苷E的含量。方法高效液相色谱法,ODSKromasal柱。水乙晴(955)为流动相,检测波长222nm,柱温度25℃。结果本文可同时测定剌五加苷B、苷E的含量。剌五加苷B、苷E分别在0.064~0.320μg/ml;0.074~0.370μg/ml范围内峰面积与浓度呈线性关系,平均回收率分别为102.5%,RSD=4.2%,95.5%,RSD=4.6%。结论剌五加苷B、苷E在红毛五加中含量最高;茎皮中含量最高;剌五加苷E的含量高于苷B。  相似文献   
37.
Carpentieri  U; Minguell  JJ; Gardner  FH 《Blood》1981,57(5):975-978
Adenylate cyclase (AC) and guanylate cyclase (GC) activities were studied in normal B-enriched and T-enriched lymphocytes, in lymphocytes of children with acute lymphocytic leukemia (ALL), and in lymphocytes of adults with chronic lymphocytic leukemia (CLL). AC activity was greater in normal B than T lymphocytes (215 pmole/min/mg protein versus 80 pmole in the membrane-enriched fraction) and i both increased greatly after stimulation with isoproterenol and more so with prostaglandins E and F2 alpha. In leukemic lymphocytes, AC showed depressed activity (20 pmole in ALL cells and 55 pmole in CLL cells) and was less sensitive to hormonal stimulation: this loss of sensitivity occurred to a greater extent in ALL than in CLL lymphocytes. GC activity was greater in normal T than B cells (in membrane-enriched fraction: 10.2 pmole versus 5.3 pmole). It increased little with isoproterenol and prostaglandins stimulation, and much more with sodium azide and dehydroascorbic acid stimulation. GC activity was increased in both types of leukemic lymphocytes (23 pmole for ALL cells and 18 pmole for CLL cells) and was insensitive to stimulation. Possible derangement of cyclase and cyclic nucleotide regulation in leukemic cells is suggested.  相似文献   
38.
The Impact of Migraine on Health Status   总被引:3,自引:0,他引:3  
Problems.-What is the effect of migraine on health status, defined as the patient's physical, psychological, and social functioning? And, suppose that the health status of migraine sufferers appears to be impaired, to what extent is this a consequence of migraine-associated comorbidity rather than of migraine itself? Methods.-A group of 846 migraineurs, selected from the general population following IHS criteria, and a control group were surveyed with the Medical Outcomes Study 36-item Short-Form Health Survey, Nottingham Health Profile, EuroQol instrument, end the COOP/WONCA charts. Questions on demographic characteristics and comorbidity were included. Results.-The health status of migraineurs appeared to be significantly impaired in comparison to the control group. Because statistical significance is distinct from relevance, effect size estimators were employed. Although the direction of the differences indicated consistently a worse health status of the migraineurs, regardless of the instrument used, the sizes of the differences were small to medium. Self-reported comorbidity, especially depression, was more prevalent in the migraine group. However, this offered only a partial explanation for the impaired health status of the migraine group. Conclusions.-Migraine has an independent moderately deteriorating effect on the daily functioning of individuals.  相似文献   
39.
人白血病HL60细胞的分化状态对细胞凋亡的影响   总被引:2,自引:0,他引:2  
用细胞培养和流式细胞术等方法,研究人白血病HL60细胞诱导分化后,对三尖杉酯碱(Har)和喜树碱(Cam)诱导细胞凋亡的影响。结果表明,12-豆蔻酰及13-乙酸佛波酯以16nmol·L-1浓度处理HL60细胞24h,细胞向单核/巨噬细胞方向分化,阻断于G1期;分化细胞抗Har和Cam诱导的细胞凋亡,但其c-myc基因的表达无变化。1.4%二甲基亚砜处理HL60细胞48h,细胞向粒细胞方向分化,阻断于G1期;分化细胞抗Cam,而不抗Har诱导的细胞凋亡;分化细胞的c-myc基因表达明显下降。结果提示,人白血病HL60细胞的分化状态,明显影响三尖杉酯碱和喜树碱诱导的细胞凋亡,但可能与c-myc基因的表达变化无关。  相似文献   
40.
Large-scale analyses of causes of neonatal deaths are usually based on death-certificate information. A new computer-based method has been introduced to define the cause of stillbirths and neonatal deaths in large amounts of material and to classify them according to two different models [Wigglesworth and Neonatal and Intrauterine death Classification according to (a)Etiology (NICE)]. The method is based on a combination of detailed information from health care registries and the death-certificate information. The present study aimed to compare these two classification models with a previously published method based solely on death certificate information [International Collaborative Effort (ICE)]. The study population comprised 2378 neonatal deaths in Sweden between 1987 and 1992. Cross-tabulation was made between the ICE classification and the other two classification models. In addition, case examples are presented in detail, exemplifying how classification errors arose. The ICE classification gives a rather low precision, notably for two important causes of death: asphyxia and immaturity. Among 328 infants dying from asphyxia according to computerized Wigglesworth classification, ICE classified 59% as asphyxia and 22% were labelled immaturity. When ICE classified the deaths as due to asphyxia, this was verified in only 50%. Among 792 infants dying from immaturity according to computerized Wigglesworth classification, 64% were classified as such by ICE. The findings cast doubts on the results of studies based exclusively on death-certificate information. Whenever possible in the analysis of neonatal deaths, death-certificate information should be supplemented with more detailed data. The computer-based method introduced here makes such analyses possible for large databases.  相似文献   
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