地学与环境研究

对地学与环境科学研究之间的关系进行了描述,说明学习、掌握了地学的基本知识,才能控制和消除环境污染,改善环境质量,维护经济活动的物质基础与生态平衡.     

Cerebrospinal fluid purine metabolites after complex febrile convulsions

Adenosine monophosphate, inosine monophosphate, inosine, adenosine, guanosine, adenine, guanine, hypoxanthine, xanthine and uric acid were determined in cerebrospinal fluid (CSF) of 15 children after complex febrile seizures (CFS) and in 27 after simple febrile seizures (SFS), and compared with those in a control group of 63 children. There was no statistically significant difference between the groups for any of these metabolites, suggesting that CFS and SFS neither significantly disturb the metabolism of nucleotides, nucleosides or bases nor significantly deplete neuron adenosine triphosphate levels.     

Continuous epidural infusion of racemic methadone results in effective postoperative analgesia and low plasma concentrations

PURPOSE: To compare two protocols of epidural administration of racemic methadone for postoperative analgesia (continuous infusion and intermittent bolus), focussing on plasma concentration, analgesic efficacy and side effects. METHODS: Ninety patients undergoing abdominal or lower-limb surgery were randomly assigned to two groups in a prospective double-blind design. The continuous infusion patients (n=60) received initial doses of 3 to 6 mg followed by 6 to 12 mg by continuous infusion over 24 hr. The bolus administration patients (n=30) received repeated boluses of 3 to 6 mg of racemic methadone every eight hours. Pain intensity was assessed on a visual analog scale. Amount of supplementary analgesia was recorded, as was the incidence of side effects. Plasma methadone concentrations were determined by high performance liquid chromatography. Treatment was continued for 72 hr. RESULTS: Pain relief was good and comparable in both groups throughout the three days of treatment. No accumulation of plasma racemic methadone was observed in either group, although the concentrations were significantly higher in the bolus group. Miosis was significantly more frequent in the bolus group. CONCLUSION: Plasma methadone concentrations were significantly lower with continuous infusion. Plasma methadone accumulation, which is considered the main disadvantage for its purported influence on the incidence of side effects, did not occur at the doses used over the three days of treatment that we report.     

雌二醇对去势前列腺癌患者LH脉冲分泌的抑制作用

３例前列腺癌施行双侧睾丸节除术后２－１２周的患，每天肌注苯甲酸雌二醇１ｍｇ，ｄ。治疗前后分别每１０ｍｉｎ采血一次，作７ｈ ＬＨ脉冲分析。结果表明，３例患平均血清ＬＨ水平分别由１７７．５８±３．２０，１３８．３０±５．８３和１４５．８８±３．８２ＩＵ／ＬＧＨＢＴＧＣ １７４．９０±７．６０，１３２．０２±５．７７和１４２．８０±３．６５ＩＵ／Ｌ（Ｐ均＜０．０１），但ＬＨ脉冲幅度和频率无明显变化（