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41.
本实验以荷 Lewis 肺癌的 NIH 小鼠为模型,以肿瘤平均直径倍增时间(MDDT)为终点,进行加温合并抗癌药物的研究。结果表明:①43℃加温25分钟,对 Lewis 肺癌有明显的治疗效果(P<0.05);②喜树碱16mg/kg合并加温25分钟,对 Lewis 肺癌的抑制作用随加热温度升高而加强,在43℃时出现相加作用(P<0.001);③斑蝥素0.45mg/kg,高三尖杉酯碱1.2mg/kg 或消瘤芥0.75mg/kg 合并加温25分钟,对Lewis 肺癌的抑制作用随加热温度升高而增强,其中斑蝥素和消瘤芥在43℃时出现协同作用(P<0.001);①去甲斑蝥酸钠3mg/kg 对 Lewis 肺癌无治疗作用,但合并43℃加温25分钟时有协同作用;⑤鸦胆子油口服乳液8ml/kg,间隔27小时合并43℃加温25分钟,对 Lewis 肺癌的治疗有相加作用,并明显延长了荷瘤动物的生存时间。  相似文献   
42.
The XIVth World Congress of Pharmacology took place July 7–12, 2002 in Moscone Convention Center, San Francisco, CA. Over 4,000 scientists, exhibitors and guests attended the Congress. It consisted of 40 symposia, 11 workshops, 18 plenary lectures and ca. 1,400 posters. The Congress was sponsored by the American Society for Pharmacology and Experimental Therapeutics, Inspire Pharmaceuticals and GlaxoSmithKline. The major financial donors were: Eli Lilly and Company, Servier, Johnson & Johnson, Merck, Novartis, Roche, Schering‐Plough, Wyeth and Yamanouchi Foundation. This report covers only presentations and posters on drugs that were attended or viewed by the author.  相似文献   
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Summary: We studied the effect of antiepileptic drugs (AEDs) on internal carotid artery (ICA) blood flow velocity, as an index of total cerebral blood flow (CBF). The subjects were 45 newly diagnosed children with febrile convulsion or epilepsy who were seizure-free for a period long enough not to affect the results. They had no neurologic deficit, received fixed monotherapy, and were examined by a noninvasive Doppler ultrasound method, in comparisonwith 13 age-matched normal volunteers with no AED. In 30 patients, the measurements were performed before and after AED administration [10 with phenobarbital (PB), 10 with carbamazepine (CBZ), and 10 with valproate (VPA)], and performed before and after AED discontinuation in the remaining 15 patients (all with PB). Normal volunteers underwent the two consecutive examinations with a mean interval equal to that of the entire patient group, and there was no difference in velocity values between the measurements. In patients receiving CBZ or VPA, a significant reduction was noted in blood flow velocity after drug administration. Although velocity values in the patients receiving PB did not change after drug administration, they were significantly increased after complete discontinuation. In the present study, a slight but significant reduction in CBF caused by AED administration at therapeutic doses in children was suggested.  相似文献   
45.
改进虎杖、鸡血藤炮制方法的研究   总被引:3,自引:0,他引:3  
对虎杖、鸡血藤作了切制、干燥时间和成品、主要成分及水浸出物的比较。结果表明,趁鲜切片优于传统切块、再切片,既能提高饮片的规格质量和成分含量,亦能减少重复劳动,节约能源,避免药材的浪费。  相似文献   
46.
Background : Nonsteroidal anti–inflammatory drugs (NSAIDs) inhibit prostaglandin synthesis which may result in impaired platelet function. Because NSAIDs have different abilities to inhibit cyclo–oxygenases we compared the effect of intravenous ketoprofen, ketorolac and diclofenac on platelet function in volunteers. Methods : Ten healthy male volunteers were given ketoprofen 1.4 mg kg-1, ketorolac 0.4 mg kg-1 and diclofenac 1.1 mg kg-1 in saline i.v. on three different occasions, at more than one–week intervals, in a randomized double–blind crossover study. Platelet function was evaluated before (sample 0), 2 (sample 2) and 24 h (sample 3) after the beginning of the infusion. Results : Two of the volunteers had no secondary platelet aggregation in their aggregation curves before the experiment (sample 0, studied three times) and their results were excluded from the final analysis. Diclofenac inhibited adrenaline (0.9 μg–ml-1) induced platelet aggregation less (median maximal aggregation 22.5%) than ketoprofen (18.3%) and ketorolac (15.7%) (P<0.05) in sample 2. In the ketorolac group in sample 3 an impairment of adrenaline (0.9 ng ml-1) induced platelet aggregation was still seen (26.7%) (P<0.05) but not in the other groups. Diclofenac did not affect adenosine diphosphate (ADP) induced platelet aggregation. However, ketorolac caused an impairment in ADP (3 μM and 6 μM) induced platelet aggregation and ketoprofen in ADP (6 μM) induced platelet aggregation in sample 2. Bleeding time was prolonged (P<0.05) after ketoprofen and ketorolac (sample 2) but not after diclofenac. Platelet retention on glass beads was unaffected by the tested drugs. Conclusion : Ketoprofen, ketorolac and diclofenac caused a reversible platelet dysfunction. Diclofenac had the mildest effect, while platelet dysfunction was still seen 24 h after the beginning of ketorolac.  相似文献   
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48.
Low density lipoprotein (LDL) has been found to represent a suitable carrier for cytotoxic drugs that may target them to cancer. This study investigated whether very low density lipoprotein (VLDL), LDL and high density lipoprotein (HDL) can be used to effectively incorporate four cytotoxic drugs, 5-fluorouracil (5-FU), 5-iododeoxyuridine (IUdR), doxorubicin (Dox) and vindesine; characterized the complexes; and examined the effect of incorporation on drug cytotoxicity against HeLa cervical and MCF-7 breast carcinoma cells. Significant drug loading was achieved into all three classes of lipoproteins, consistent with the sizes and hydrophobicity of the drugs. The relative loading efficiency was found to be vindesine>IUdR>Dox>5-FU for all three classes of lipoproteins. As shown by electron microscopy (EM), drug incorporation did not affect the size or morphology of the lipoproteins. Differential scanning calorimetry (DSC) showed that drug loading did not significantly change the thermal transition temperature of core lipids in the lipoproteins. The transition enthalpy was changed only for LDL–Dox and LDL–vindesine. The drugs remained stable in the lipoproteins as determined by high performance liquid chromatography (HPLC). EM, DSC and HPLC data suggest that drugs were incorporated into lipoproteins without disrupting their integrity and drugs remained in their stable forms inside lipoproteins. Compared with free drugs in cytotoxicity assays, the IC50 values of LDL– and HDL–drug complexes were significantly lower (2.4- to 8.6-fold for LDL complexes and 2.5- to 23-fold for HDL complexes). All free or lipoprotein-bound drug formulations were comparably more cytotoxic against MCF-7 than HeLa cells. Upregulating the lipoprotein receptors enhanced, and downregulating them inhibited, the cytotoxicity, indicating the mechanistic involvement of lipoprotein receptor pathways. Complexes of all four drugs with VLDL, in contrast to LDL and HDL, had the same cytotoxicity as the four corresponding free drugs. Our results suggest that further studies are required of the potential of HDL to be a cancer targeting drug carrier.  相似文献   
49.
Summary:  Status epilepticus (SE) is a medical emergency which can lead to significant morbidity and mortality and requires prompt diagnosis and treatment. SE is differentiated into generalized or partial SE on the basis of its electro-clinical manifestations. The guidelines for the management of SE produced by the Italian League against Epilepsy also distinguish three different stages of SE (initial, established and refractory), based on time elapsed since the onset of the condition and responsiveness to previously administered drugs. Treatment should be started as soon as possible, particularly in generalized convulsive SE, and should include general support measures, drugs to suppress epileptic activity and, whenever possible, treatments aimed at relieving the underlying (causative) condition. Benzodiazepines are the first line antiepileptic agents, and i.v. lorazepam is generally preferred because it is associated with a lower risk of early relapses. If benzodiazepines fail to control seizures, i.v. phenytoin is usually indicated, though i.v. phenobarbital or i.v. valproate may also be considered. Refractory SE requires admission to an intensive care unit (ICU) to allow adequate monitoring and support of respiratory, metabolic and hemodynamic functions and cerebral electrical activity. In refractory SE, general anesthesia may be required. Propofol and thiopental represent first line agents in this setting, after careful assessment of potential risks and benefits.  相似文献   
50.
采用中药与行为干预综合治疗的方法对140名轻、中度精神发育迟滞的儿童进行分组康复观察。结果发现中药加行为干预组治疗后智力商数(IQ)及能力的变化最大,明显优于单用中药组和单纯行为干预组(P<0.01);与对照组相比有非常显著的差异(P<0.001)。从而为精神发育迟滞儿童的康复治疗提供了新的途径。  相似文献   
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