七氟醚闭环靶控麻醉的临床研究

由于控制变量采样频率和药物输注速度调节迅速,闭环控制麻醉更易维持麻醉深度和患者血液动力学的稳定,从而提高麻醉质量。本研究使用吸入麻醉控制程序,对结肠部分切除患者进行七氟醚(Sevoflurane)闭环靶控麻醉,观察麻醉控制效果并与传统手动控制麻醉相比较。     

七氟醚的新法合成

以丙酮为原料,经氯化、气相氟化、气相氢化及氟甲基化等一系列改进的方法合成了七氟醚,提供了一条新的合成路线。氯化产率为８６７％,氟化选择性为９５％,氢化选择性为１００％,氟甲基化产率为４２％。     

七氟醚合成工艺的改进

以六氟异丙醇、多聚甲醛和三氯化铝为原料在催化剂的作用下反应得到氯甲基2,2,2-三氟-1-(三氟甲基)乙基醚,再与氟化钾反应合成七氟醚。最佳原料配比为:六氟异丙醇∶多聚甲醛∶三氯化铝∶氟化钾=1∶1∶1.1∶2(摩尔比)。合成氯甲基-1,1,1,3,3,3-六氟异丙基醚的最佳反应温度为30℃。七氟醚的最佳反应时间为12 h,最佳反应温度为80℃。考察了反应时间、反应温度、催化剂用量等对反应的影响,七氟醚的纯度达到99.3%(GC),收率达到70.4%。     

七氟醚对脑的保护作用及研究进展

七氟醚(Sevoflurane,Sev)为全身性的吸入性麻醉药,有着诱导和清醒较快,对人体器官副作用影响小,兼并稳定血流动力学的优点。同时对呼吸道的刺激小,现如今常常被广泛应用于临床麻醉中,相关研究表明七氟醚对心、脑、肾等重要器官都有着很好的保护作用现根据研究现状,本文主要基于七氟醚对脑神经功能的可能产生的保护作用及各种相关机制进行探讨。     

异氟醚的最新进展

综述了异氟醚的国内外制备方法、分离提纯方法,建议应当通过萃取剂的选择来提高国内异氟醚的品质。     

对腹腔镜胆囊切除术病人采用两种麻醉方法所产生应激反应的临床研究

本文选择在气管插管全麻下择期行腹腔镜胆囊切除术的病人50例,在通过BIS监测,在相同麻醉深度下比较丙泊酚与七氟醚对老年病人应激反应的影响,从而为临床老年病人的麻醉选择合适的麻醉方法以及合理的全麻用药提供客观依据。     

异氟醚和异丙酚用于颅脑手术的比较

目的比较异氟醚和异丙酚在颅脑外科手术中的应用效果,探讨颅脑外科手术较理想的麻醉方法。方法选择ASAI-Ⅱ级且无心血管疾病的颅脑手术患者60例,随机分成两组,静脉诱导全麻插管后,组I采用全凭静脉全麻,泵入异丙酚维持麻醉,组II为吸入全麻,采用异氟醚吸入维持麻醉。两种均采用氯化琥珀胆碱静滴维持肌松。手术过程中监测收缩压、舒张压、心率、心电图和脉搏血氧饱和度。结果组I患者血压,心率波动及心血管反应明显,组II较平稳,与组I比较有显著性差异(P<0.05),且组II较组I清醒迅速。结论静脉诱导,吸入维持的复合全麻是颅脑外科手术较理想的麻醉方法。     

耐低温氟醚橡胶的现状和进展

综述了耐低温氟醚弹性体的典型结构、主要性能和配合特点。     

三氟羧草醚的合成

介绍了以对氯三氟甲苯为起始原料合成三氟羧草醚的工艺。经过中试试验,证明了本工艺安全可靠,产品质量好,收率高。     

羧基氟草醚中间体的气相色谱分析

本文介绍了合成除草剂羧基氟草醚的中间体3-[2-氯-4-(三氟甲基)-苯氧基]苯甲酸的气相色谱分析方法。试验在2m5％OV-17柱上,用氢焰检测器能对其甲酯化产物有较稳定的分析特性,回收率在100±0.56％,标准偏差为3.27×10~(-3),变异系数为0.36％。     

轻比重小剂量蛛网膜下腔-硬膜外联合麻醉在下肢骨折老年患者手术中的应用

目的 探讨轻比重小剂量蛛网膜下腔-硬膜外联合麻醉在下肢骨折老年患者手术中的应用安全性和麻醉效果。方法 对54例老年下肢骨折手术的患者临床资料进行回顾性分析。结果 患者麻醉后的SBP、DBP较麻醉前略有下降,但比较无显著差异(P>0.05),HR和SPO2较麻醉前略有升高,比较亦无显著差异(P>0.05)。结论 小剂量轻比重蛛网膜下腔-硬膜外联合麻醉对行下肢手术的老年骨折患者是一种疗效确切,安全可靠的麻醉方法。     

Changes in Plasma LDL and HDL Composition in Patients Undergoing Cardiac Surgery

Changes of lipoprotein composition have been mainly reported in conditions of sepsis. This study characterized compositional changes in LDL and HDL during the acute phase response following cardiac surgery with cardiopulmonary bypass. Twenty-one patients undergoing cardiac surgery were included in this study. Blood samples were drawn before operation and on day 2 post-surgery. In parallel to plasma lipids and antioxidant status, lipoproteins were analyzed for lipid, apolipoprotein (apo), hydroperoxide and alpha-tocopherol content. Beyond decreases in lipid concentrations and antioxidant defenses, cardiac surgery induced substantial modifications in plasma lipoproteins. ApoB decrease in LDL fraction (−46%; P < 0.0001) reflected a marked reduction in the circulating particle number. LDL cholesteryl ester content relative to apoB concentration remained unchanged post-surgery while triglyceride (+113%; P < 0.001), free cholesterol (+22%; P < 0.05) and phospholipid (+23%; P < 0.025) were raised relative to apoB indicating increased particle size. In HDL, an abrupt rise of apoSAA (P < 0.05) was observed together with a decrease of apoA1 (−22%; P < 0.005). Cholesteryl ester content in HDL fraction decreased in parallel to apoA1 concentration while triglycerides, free cholesterol and phospholipids increased relative to apoA1. In contrast to unchanged alpha-tocopherol content, hydroperoxide content was increased in LDL and HDL. By comparison to sepsis, cardiac surgery induces a comparable reduction in circulating LDL but a more limited decrease in HDL particles. Furthermore, in contrast, cardiac surgery induces an increase in polar and non-polar lipids, as well as of particle size in both LDL and HDL. M. Hacquebard is recipient of a fellowship from the Danone Institute, Belgium.     

Non-Uniformity of Surface Temperatures of Grain after Microwave Treatment in an Industrial Microwave Dryer

In this study, temperature rise and non-uniformity of heating of grain with different moisture contents after microwave treatment were investigated. The temperature anomalies after microwave treatment were measured for barley and wheat at four moisture levels (12, 15, 18, and 21% wet basis) and for canola at five moisture levels (8, 12, 15, 18, and 21% wet basis). Fifty grams of grain samples were heated in a laboratory scale, continuous-type, industrial microwave dryer (2450 MHz) at five power levels (100, 200, 300, 400, and 500 W) and two exposure times (28 and 56 s). Grain samples were thermally imaged using an infrared thermal camera as soon as they came out from the microwave chamber. Average, maximum, and minimum temperatures were extracted from each thermal image and the difference between maximum and minimum temperatures (ΔT) was calculated. The grain type had significant effect on the surface temperatures after microwave treatment. The surface temperatures increased with microwave powers and exposure times but decreased with moisture content. The average surface temperatures after microwave treatment were between 72.5 and 117.5°C, 65.9 and 97.5°C, and 73.4 and 108.8°C for barley, canola and wheat, respectively, when the applied microwave power was 500 W. At the same power level, the maximum surface temperature was between 100.3 and 140.0°C, 77.8 and 117.7°C, and 98.3 and 130.9°C for barley, canola, and wheat, respectively. Non-uniform heating patterns were observed for all three grain types at all moisture contents, power levels, and exposure times. The ΔT was in the range of 7.2 to 78.9°C, 3.4 to 59.2°C, and 9.7 to 72.8°C for barley, canola, and wheat, respectively. The location of hot and cold spots may vary in different dryers based on the position of magnetron and other components, but almost similar non-uniform heating pattern is expected in all microwave dryers. Therefore, this non-uniformity must be taken into consideration while developing microwave processing systems for grains.     

Degradation and Nutritional Quality Changes of Oil During Frying

The changes in regular canola oil as affected by frying temperature were studied. French fries were fried intermittently in canola oil that was heated for 7 h daily over seven consecutive days. Thermo-oxidative alterations of the oil heated at 185 ± 5 or 215 ± 5 °C were measured by total polar components (TPC), anisidine value (AV), color components formation, and changes in fatty acid composition and tocopherols. Results showed that TPC, AV, color and trans fatty acid content increased significantly (P < 0.05) as a function of frying temperature and time. The oil polyunsaturated fatty acids (PUFA) decreased in direct proportion to frying temperature and time. After 7 days of frying, the amount of PUFA was reduced by half and the trans isomers contribution increased 2.5 times during frying at 215 °C. Of the parameters assessed, total polar component and color had the highest correlation, with correlation coefficients of 0.9650 and 0.9302 for frying at 215 and 185 °C, respectively. TPC formation correlated inversely with the reduction of tocopherols.     

渣油在加氢处理中的氮分布和氮类型变化

采用氮分布和酸电位滴定分析技术对渣油在加氢处理中试装置上的氮含量及氮类型变化进行定量研究,结果表明：氮的总脱除率为42.36%,在上流式和固定床两个阶段的脱除率分别为26.76%和15.60%。焦化蜡油和减压渣油混合成的原料渣油的氮含量呈＂U＂型分布。随着加氢深度增加,芳香分中的氮含量降低,而胶质和沥青质中的氮含量增加。氮在渣油四组分中的分布规律是芳香分组分〉胶质组分〉沥青质组分。在加氢处理过程中,总氮、碱性氮和非碱性氮含量逐渐降低,但非碱性氮占总氮的质量分数呈降低趋势,而碱性氮占总氮质量分数呈增加趋势。     

预氧化过程中聚丙烯腈纤维结构与性能的变化

综述了聚丙烯腈(PAN)纤维在预氧化过程中的反应机制,分析了预氧化过程中纤维颜色、元素含量、纤维结构、力学性能的变化以及金属离子对于预氧化的影响。结果表明:PAN原丝在预氧化过程中发生的环化、氧化、脱氢反应,在很大程度上受到预氧化温度、预氧化时间和施加在纤维上的张力的影响。     

PAN基预氧化纤维碳化过程中结构与性能变化

综合论述了聚丙烯腈(PAN)基预氧化纤维在碳化过程中的物理化学变化,包括裂解气体、化学反应以及由此引起的纤维结构、强度、弹性模量、断裂延伸率、直径、体密度、断裂方式的变化。     

地表水中氨氮的变化及检测中的质量控制

介绍了地表水中氨氮的变化规律和检测时为使测定结果准确、可靠而应注意的质控措施。     

Immunohistochemical Analysis of Paraoxonases and Chemokines in Arteries of Patients with Peripheral Artery Disease

Oxidative damage to lipids and lipoproteins is implicated in the development of atherosclerotic vascular diseases, including peripheral artery disease (PAD). The paraoxonases (PON) are a group of antioxidant enzymes, termed PON1, PON2, and PON3 that protect lipoproteins and cells from peroxidation and, as such, may be involved in protection against the atherosclerosis process. PON1 inhibits the production of chemokine (C–C motif) ligand 2 (CCL2) in endothelial cells incubated with oxidized lipoproteins. PON1 and CCL2 are ubiquitously distributed in tissues, and this suggests a joint localization and combined systemic effect. The aim of the present study has been to analyze the quantitative immunohistochemical localization of PON1, PON3, CCL2 and CCL2 receptors in a series of patients with severe PAD. Portions of femoral and/or popliteal arteries from 66 patients with PAD were obtained during surgical procedures for infra-inguinal limb revascularization. We used eight normal arteries from donors as controls. PON1 and PON3, CCL2 and the chemokine-binding protein 2, and Duffy antigen/chemokine receptor, were increased in PAD patients. There were no significant changes in C–C chemokine receptor type 2. Our findings suggest that paraoxonases and chemokines play an important role in the development and progression of atherosclerosis in peripheral artery disease.