Minimum alveolar concentration for halothane in children with cerebral palsy and severe mental retardation

Children with cerebral palsy and severe mental retardation who present for operation may require lower concentrations of inhalational anaesthetics than healthy children. The minimum alveolar concentration (MAC) for halothane was measured in 36 children and adolescents, aged 4–18 years, who underwent orthopaedic surgery. The control group consisted of 12 healthy children (group 1). Children with cerebral palsy and severe mental retardation were allocated to one of two groups: those taking chronic anticonvulsant medication (group 2) ( n  = 12) and those who did not take any drugs (group 3) ( n  = 12). The mean (SEM) MAC value for halothane (expressed in volume per cent) was 0.90 (0.02) for healthy children. Children with cerebral palsy had significantly lower MAC values whether they took anticonvulsant drugs or not (0.62 (0.03) and 0.71 (0.10), respectively).     

Minimum alveolar concentration of sevoflurane for tracheal extubation in children

Background: One advantage of tracheal extubation during deep anaesthesia is that respiratory complications are reduced. Sevoflurane is a suitable anaesthetic agent for children. This study was conducted to determine the minimum alveolar concentration of sevoflurane required to prevent cough or movement during and after tracheal extubation (MAC_extubation).
Methods: We studied 30 nonpremedicated children, aged 2–10 yr, undergoing plastic surgery. They were allocated randomly to five groups (end-tidal sevoflurane concentrations: 2.0, 2.5, 3.0, 3.5, 4.0%). After surgery, 60% nitrous oxide was discontinued and the target concentration of sevoflurane was maintained for at least 10 min in 100% oxygen, then the trachea was extubated to determine MAC_extubation. Logistic regression was used to estimate MAC_extubation. of sevoflurane.
Results: MAC_extubation. was 2.3 (0.2; standard error)% (95% confidence limits: 1.2% and 2.7%).
Conclusions: Tracheal extubation in 50% of anaesthetized children age 2–10 yr may be accomplished without coughing or moving at 2.3% end-tidal concentration of sevoflurane.     

天然野生和种植药用蔓荆子化学成分研究──Ⅰ．天然野生和种植药用蔓荆子挥发油成分定性研究

本文采用水蒸气蒸馏提出挥发油，并利用不同类型的毛细管柱，找出最佳色谱分离条件，再利用气相色谱－质谱－计算机系统将色谱分离出的３５种成分进行鉴定，从中定性了２１种成分，占总挥发油成分的６０％。从ＧＣ－ＭＳ鉴定结果看，天然野生蔓荆子比种植药用蔓荆子缺少了氯代甲烷、二氯甲烷、氯仿和１－甲氧基－４－（２－丙烯基）苯，因此，两者在挥发油成分上极为相似，有进一步研究开发利用的价值。     

Effect of nitrous oxide and volatile anaesthetics on platelet function in man

Twelve otherwise healthy male volunteers scheduled for arthroscopy of the knee were studied. The influence in vivo of nitrous oxide (N₂O) per se and the addition of a halogenated volatile anaesthetic (halothane or isoflurane) on ADP–induced platelet aggregation and release of beta–thromboglobulin into plasma was evaluated. All measurements were made before surgery. We found that N₂O increased platelet aggregation. Adding a halogenated anaesthetic reversed the relative hyperaggregation induced by N_aO. The concentrations in plasma of the platelet release product beta thromboglobulin were not influenced by the anaesthetics.     

Evaluation of the genetic toxicity of middle distillate fuels

Petroleum middle distillate (PMD) fuels are mixtures of hydrocarbons that distill between ～ 170-370°C. Commercial products that fall into this category include kerosine, diesel fuel, jet fuel, and home heating oil. These products contain both saturated (paraffins and cycloparaffins) and aromatic species, but because of the boiling range normally contain very small amounts of the 3-6 ring polycyclic aromatic hydrocarbon (PAH) constituents, which are considered to be carcinogenic. Nevertheless, there is evidence of weak tumorigenic activity when these materials are repeatedly applied to mouse skin. In the current studies representative products were tested in two commonly used, short-term assays for genetic toxicity, the Salmonella/mammalian microsome mutagenicity assay and the mouse bone marrow micronucleus test. All samples were inactive in the micronucleus assay, and three were clearly inactive in the Salmonella test. Of the remaining two, one was marginally active in the Salmonella assay, and one was equivocal. The marginally active sample contained detectable levels of PAH due to the use of catalytically cracked materials as blending stocks. The results indicated that PMDs that do not contain cracked material were not mutagenic. Thus they may produce tumors via nongenotoxic processes. Those products that do contain cracked stocks may have sufficient PAH to be mutagenic in the Salmonella assay, and in those cases the PAH might also contribute to tumor formation. © 1994 Wiley-Liss, Inc.     

挥发油提取过程动力学模型及其参数的确定

目的：探讨中药材挥发油提取过程的动力学模型及其参数。方法：将挥发油的提取过程模拟为人体静注给药经肾脏的消除过程，并采用亏量法和速率法求解其动力学方程。结果：中药材挥发油提取过程的动力学模型为：Vt=Vt^m(I-e^kt),ln(Vt^∞-Vt)=-kt lnVt^∞,lnΔVt/Δt=-ktc lnkeVt.结论：该动力学模型与挥发油实际提取过程相似，可有效指导工业生产。     

烹调油烟与女性肺癌关系的Meta分析

目的探讨烹调油烟与女性肺癌的关联程度。方法采用Meta分析的方法,对在国内外公开发表的8篇有关烹调油烟与非吸烟女性肺癌的流行病学研究文献进行综合定量再分析。根据资料一致性检验,采用固定效应模型计算总OR值。结果烹调油烟接触与非吸烟女性肺癌之间总的合并OR值为2.94,其95%CI为2.43～3.56,差异有显著意义(χ2=120.64,P<0.01)。结论烹调油烟与女性肺癌具有高度的联系,是女性肺癌的重要危险因素。     

视网膜脱离硅油充填术继发性青光眼临床观察

目的 探讨视网膜脱离硅油充填术继发性青光眼的相关因素及硅油取出对继发性青光眼的影响。方法 统计玻璃体切除硅油充填术视网膜复位后行硅油取出的病例，并对继发性青光眼的发生及其转归进行了随访观察。结果 120例121眼中25眼发生继发性青光眼(20．66％)，硅油取出后经1-3月随访23眼眼压降至正常，2眼药物控制。结论 随着硅油在眼内停留时间的延长继发性青光眼的发生率明显增加，玻璃体切除硅油充填术后以在视网膜复位后3-6月取出为宜。一旦发生继发性青光眼即是硅油取出的指征。     

三种食用油对小鼠脂质过氧化的影响及其意义

选用４月～６月龄的小鼠，分别饲以多不饱和脂肪酸含量下同的猪油，花生油及豆油，观察其对机体脂质过氧化的影响，结果发现，血浆及肝中脂质过氧化产物丙二醛仿猪油低于花生油组及豆油组，肝中超氧化物歧化酶含量前者高于后二者，有显著性关系，花生油组与豆油可增强机体脂质过氧化，而猪油则相反，故而多种食用油合理塔配应用有利于健康。     

无水乙醇碘油乳剂经肝动脉栓塞治疗肝癌疗效观察

４２例肝癌患者，栓后肿瘤缩小率大于５０％占６１．９％，缩小率小于２５％占１２％；５０％的患者栓后ａ－ＦＰ降至正常。６个月、１２个月、１８个月生存率分别为９１．４％、７１．４％及５０％。所有患者匀可耐受治疗，无１例出现严重并发症，因此，我们认为：无水乙醇碘油乳剂经肝动脉栓塞治疗肝癌疗效显著，且安全。