Sodium removal and sodium concentration during peritoneal dialysis: effects of three methods of sodium measurement.

BACKGROUND: Sodium removal (NaR) may have a major impact on the survival of peritoneal dialysis patients. The dialysate/plasma sodium concentration ratio (D/P(Na)) is an indirect index of transcellular water transport by aquaporin channels, and thus of ultrafiltration. Sodium concentration can be assessed by means of flame photometry (F), and direct (D-ISE) or indirect ion-selective electrodes (I-ISE), but these methods have different properties. I-ISE is being used increasingly in clinical laboratories. The aim of this study was to evaluate NaR and D/P(Na) using the three different measurement methods. METHODS: We performed peritoneal equilibration tests (PETs) in 44 peritoneal dialysis patients and calculated the NaR. We also calculated D/P(Na) during the test; plasma and dialysate sodium concentrations were measured by F, D-ISE and I-ISE. RESULTS: NaR was lower (P<0.001) with D-ISE (69+/-29 mmol) than with F (81+/-29 mmol) or I-ISE (79+/-28 mmol). D/P(Na) was also lower at baseline (0.92+/-0.02 vs 0.95+/-0.02 and 0.95+/-0.02; P<0.001), after 60 min (0.87+/-0.03 vs 0.90+/-0.03 and 0.90+/-0.03; P<0.001) and at the end of PET (0.88+/-0.04 vs 0.92+/-0.04 and 0.92+/-0.04; P<0.001) when measured by D-ISE in comparison with F and I-ISE, respectively. CONCLUSIONS: NaR and D/P(Na) were lower when measured by the D-ISE method compared with the F and I-ISE methods. NaR and D/P(Na) were similar when measured by F or I-ISE. I-ISE can be used reliably in the evaluation of NaR and D/P(Na) in everyday clinical practice of peritoneal dialysis.     

急性重型脑损伤患者脑组织氧代谢监测及意义

目的　探讨对急性重型脑损伤患者行脑组织氧代谢监测的临床意义。　方法对2 8例急性重型脑损伤患者 (均在全麻下急诊行血肿清除术和 (或 )去骨瓣减压术 )术中及术后持续进行脑组织氧代谢监测 ,观察脑组织氧分压 (PbtO2 )、二氧化碳分压 (PbtCO2 )和pH值 (pHbt)的变化。　结果　 (1) 2 8例脑外伤患者在剪开硬脑膜后PbtO2 、pHbt分别从 (13± 4 )mmHg、(6 .96± 0 .15 )增加至 (2 1± 5 )mmHg、7.0 5± 0 .12 (P <0 .0 5 ) ,PbtCO2 从 (6 1± 6 )mmHg下降至 (5 3± 5 )mmHg(P <0 .0 5 )。(2 )其中 2 4例脑外伤患者在血肿清除后 ,PbtO2 、pHbt值分别从 (2 1± 4 )mmHg、7.0 5± 0 .11增加至 (2 8± 6 )mmHg、7.15± 0 .10 (P <0 .0 5 ) ,PbtCO2 从 (5 2± 6 )mmHg下降至 (4 5± 4 )mmHg(P <0 .0 5 )。 (3)PbtO2 <10mmHg持续 30min以上的患者预后差。　结论　 (1)脑组织氧代谢监测是一种安全、可靠的监测手段 ,能直接动态反映脑组织的病理生理变化 ,及时发现脑组织缺血缺氧 ,以指导治疗。 (2 )持续进行脑组织氧代谢监测可判断重型脑外伤患者的预后。     

Dysphoric Rumination Impairs Concentration on Academic Tasks

Three studies investigated the effects of dysphoric rumination on concentration during 3 academic tasks—reading a passage from the GRE (Study 1), watching a videotaped lecture (Study 2), and proofreading written text (Study 3). Before performing these tasks, dysphoric and nondysphoric students were induced either to ruminate about themselves or to distract themselves by focusing on neutral images (all three studies) or by planning an event (Study 1). The results supported our hypothesis that dysphoric rumination, relative to distraction, would impair students' concentration. In all 3 studies, dysphoric ruminators reported difficulty concentrating, as well as interfering thoughts, during the relevant academic tasks. Furthermore, dysphoric ruminators were slower than dysphoric distractors in completing the tasks—specifically, reading the GRE passage (Study 1) and answering lecture comprehension questions (Study 2). In addition, dysphoric participants who ruminated showed impaired reading strategies (Study 1), reduced comprehension of academic material (Study 2), and poor proofreading performance (Study 3). These findings suggest that, in addition to its documented adverse effects on mood, thinking, and problem-solving, self-focused rumination interferes with instrumental behavior. Implications for social relationships and job performance are discussed.     

佛山市城区室内装修污染特征初探

目的 为了解佛山市室内装修空气污染状况，通过对佛山市室内装修污染物进行调查，掌握室内装修污染的一些基本特征并提出控制措施。方法 根据卫生部《室内空气质量卫生规范》以及《室内空气污染物的检验方法》方案，调查采用了问卷调查和现场检测的方法。结果 佛山市室内装修空气污染物主要为甲醛，苯，总挥发性有机物(TVOC)，超标率分别为86％，36％，23％。结论 目前佛山市城区室内装修污染物的特征为：有机污染较无机污染严重，室内甲醛污染严重，苯次之而氢污染相对较轻，室内空气苯污染车辆、居室高于办公室，甲醛污染居室，办公室高于车辆。     

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。     

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.     

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     

茶碱及其缓释剂在可逆性气道痉挛中疗效观察及血药浓度监测对照研究

目的 无水茶碱修筛缓释片——优喘平(portheo)治疗可逆性支气管阻塞患者(FEV_1<预计值80％)30例。观察其疗效及安全性,同时监测其STLD(血清浓度),并与氨茶碱片口服后STLD进行比较。结果显示;优喘平治疗哮喘及慢性阻塞性肺病疗效达90.6％,三例有轻微副作用。优喘平服用后4小时STLD即达有效浓度,8小时后STLD多维持在有效水平,峰值多<20ug/ml。氨茶碱0.1/次,3次/日,连服4天后STLD谷值多<5ug/ml,0.2/次,3次/日,连服4天后STLD谷值均>5ug/ml,峰值均>20ug/ml,且多有较重毒付作用。优喘平0.4/次,1次/日与氨茶碱0.1/次,3次/日比较,疗效好,而比氨茶碱0.2/次,3次/日,毒付反应少。优喘平与氨茶碱有显著差异。(P<0.01)。