深低温对吸入麻醉药的MAC,心脏麻醉指数和心肌稳定性的影响

目的:研究深低温对吸入麻醉药MAC、心脏麻醉指数和心肌稳定性的影响。方法:新西兰白兔40只,随机分为氟烷、安氟醚、异氟醚和七氟醚组。采用夹尾试验法测定常温下(38℃±0.5℃)的最低肺泡有效浓度(MAC)。行体表降温后测定深低温下(23℃±0.5 ℃)的MAC。维持深低温增加吸入性麻醉药的浓度,同时用50Hz、25V电压胸外电击心脏。记录出现室颤或室性心律失常时的肺泡呼气末吸入麻醉药浓度。结果:从38℃到23℃兔体温每降低1℃,MAC下降值为:氟烷5.1％、安氟醚3.6％、异氟醚4.4％、七氟醚4.3％;氟烷、安氟醚、异氟醚和七氟醚心脏麻醉指数分别为4.4、3.18、6.25和4.6,异氟醚明显高于其它麻醉药;麻醉药浓度8MAC以内安氟醚和氟烷发生室颤的机率(100％)明显高于七氟醚和异氟醚(40％)。结论:异氟醚是深低温麻醉的最佳选择用药,而安氟醚则不宜用于低温麻醉。     

特发性脊柱侧凸King型和型远端融合椎的选择

目的回顾采用椎弓根钩和螺钉CD技术治疗特发性脊柱侧凸King型和型患者,分析选择性缩短融合节段的治疗效果。方法2000年3月~2003年1月,治疗58例特发性脊柱侧凸单胸弯患者,男17例,女41例,年龄12~18岁,平均14岁。其中King型40例,King型18例。胸弯Cobb角平均64°(50~83°),柔韧性62%;腰弯Cobb角平均37°(16~48°),柔韧性105%。腰弯腰骶角平均为17°(10~22°)。所有患者C7重力垂线均不同程度地偏离骶骨中线。采用椎弓根钩和螺钉CD技术矫形治疗,以中立椎为基础选择远端融合椎,所有远端融合节段均未超过中立椎。术后随访摄站立前后位和侧位X线片,观察各项指标的变化。结果患者均获随访1年8个月~3年2个月,平均2.4年,均未出现明显的躯干侧方移位和双肩不平衡。术后Cobb角平均丢失3.1°(-1~5°);最后随访时,胸弯矫正率68%;除2例C7重力垂线偏离骶骨中线1~2cm外,其余均通过骶骨中线;腰弯腰骶角减少至平均8°(2~13°),矫正率为53%;48例远端融合椎为非稳定椎者术后成为稳定椎。与Harrington远端融合椎选择原则相比,患者远端融合椎平均节省1.4个节段(1~2个节段)。结论采用三维节段性器械内固定系统治疗特发性单胸弯时,以中立椎为基础选择远端融合椎,可获得较好的临床效果。     

高效液相色谱法测定头孢他啶血药浓度

目的建立测定头孢他啶血药浓度的方法。方法高效液相色谱法采用Kromasil C18色谱柱（250mm×4．6mm，5μm），以甲醇-磷酸二氢钾溶液（15：85）为流动相，流速1．0ml／min，检测波长254nm。结果头孢他啶吼浆浓度在0．5～200．0mg·L^-1范围内线性笑系良好（r=0．9999）。低、中、高3个浓度的方法回收率为94．91％～105．95％，RSD〈12％；提取回收率为89．50％～92．94％，RSD〈5％。结论本方法简便、准确、精密度好，可用于临床药动学研究。     

hCG/ATP-induced Leydig cell calcium channel reaction at different extracellular calcium ion concentration

Objective: To study the calcium channel reaction of human Leydig cells induced by hCG/ATP at different extracellular calcium ion concentrations. Methods: The Leydig cell calcium ion concentration was examined with laser confocal microscope, when the cells were stimulated with hCG/ATP at different extracellular calcium contrations. Results: With calcium-containing extracellular fluid, the Leydig cells were sensitive to hCG stimulation and when the extracellular fluid was calcium-free, the Leydig cells did not respond to the stimulation. However, the Leydig cells did respond to ATP stimulation no matter the extracellular fluid contained calcium or not. Conclusion: In human Leydig cells, there are calcium channels sensitive to hCG and ATP. The extracellular calcium ion concentration plays an important role in the regulation of Leydig cell metabolism by hCG/ATP.     

微波凝固联合黏膜下氟尿嘧啶注射治疗早期低位直肠癌

目的探讨微波凝固联合黏膜下氟尿嘧啶（5-Fu）注射治疗早期低位直肠癌的适应证和疗效。方法1996年1月～2002年12月对9例早期低位直肠癌采用微波凝固联合黏膜下5-Fu注射，微波治疗后用含5．Fu1．0g的生理盐水100～200ml保留灌肠，1次／d，连续3d，随访其疗效。结果3例微波治疗前CEA增高，微波治疗后CEA下降至正常。术中、术后无出血等并发症。随访至2006年1月，9例全部存活。l例生存3年5个月；1例生存3年8个月；1例1年4个月后肿瘤复发，行Miles手术至今又生存2年9个月；6例生存5年以上，其中1例5年1个月，1例6年3个月，l例6年8个月，1例7年6个月，2例9年。结论微波凝固联合黏膜下5-Fu注射治疗早期低位直肠癌适应于早期、距肛缘7cm以下、肿块型、肿瘤直径0．5～3．0cm或肿瘤〈直肠周径的1／3、病理类型为高分化肿瘤、且患者强烈要求保肛的直肠癌。该方法具有创伤小、费用低和疗效满意等特点。     

A theophylline dosage regimen which reduces round-the-clock variations in plasma concentrations resulting from diurnal pharmacokinetic variation

Summary Slower drug absorption at night can leave residual drug from an evening dose of a sustained-release product remaining to be absorbed at the time of the next morning's dose, thereby giving higher plasma concentrations of the drug during the day than the night.When a capsule product releasing theophylline over 12 h after a morning dose was given repetitively at 8 a.m. and 8 p.m. for 4 days, daytime plasma concentrations from 4 h to 8 h after the dose were about 40% greater than corresponding night-time concentrations, and the mean steady-state concentration during the night-time interval was only 81% of that during the daytime interval.Altering the regimen to one capsule at 12 noon and one at 10 p.m. eliminated all significant differences between a.m. and corresponding p.m. plasma concentrations of theophylline and between the mean steady-state concentrations for each of the interdose intervals within a day.     

儿童地高辛血药浓度的回顾性分析

目的 :探讨血药浓度监测对个体化、合理化用药的重要作用。方法 :荧光偏振免疫法 (FPIA)和通过近十年住院病人地高辛用药的回顾性分析。结果 :地高辛血药浓度监测结果分三个范围 :低值小于 0 .8μg/ L,中值 0 .8～ 2 .2 μg/ L,高值大于 2 .2μg/ L。对实验数据进行统计 ,得出有效浓度范围内的病人占 4 0 %左右 ,低值平均约 >5 0 % ,高值平均为 6 .1%。结论 :通过对地高辛用药的监测回顾 ,说明地高辛的药物代谢过程受许多因素如吸收、分布、代谢、排泄、药物间的相互作用等的影响。所以临床在用药过程中 ,药物浓度的监测对实施个体化、合理化用药 ,减少药物中毒的发生起着重要作用     

Symptoms of contruction workers exposed to whole body vibration and local vibration

Summary To study the effects of construction machinery operation on subjective symptoms, a questionnaire survey was caried out among construction machinery operators by a self-reporting method. Subjects were 184 power shovel operators, 127 bulldozer operators, 44 forklift operators as operator groups, and 44 office workers as a control. Their ages were in a range of 30–49 years. The questionnaire contained 20 symptoms referring to fatigue, digestive problems, and upper or lower limbs or back problems. The prevalence rate and symptom characteristics were examined. The dominant symptoms of the operator groups were stiff shoulder, low back pain, and stomack symptoms. The prevalence rate of low back pain was significantly different between forklift operators and controls. No significant differences were found in the symptoms of upper limbs and fingers between operator groups and controls. The prevalence of Raynaud's phenomenon was 0.5%–2.3% in the operator groups and 2.3% in the control group.     

High-quality recording of bioelectric events

A multichannel instrumentation amplifier, developed to be used in a miniature universal eight-channel amplifier module, is described. After discussing the specific properties of a bioelectric recording, the difficulties of meeting the demanded specifications with a design based on operational amplifiers are reviewed. Because it proved impossible to achieve the demanded combination of low noise and low power consumption using commercially available operational amplifiers, an amplifier equipped with an input stage with discrete transistors was developed. A new design concept was used to expand the design to a multichannel version with an equivalent input noise voltage of 0·35 μV RMS in a bandwidth of 0·1–100 Hz and a power consumption of 0·6 mW per channel. The results of this study are applied to miniature, universal, eight-channel amplifier modules, manufactured with thick-film production techniques. The modules can be coupled to satisfy the demand for a multiple of eight channels. The low power consumption enables the modules to be used in all kinds of portable and telemetry measurement systems and simplifies the power supply in stationary measurement systems.