99Tcm-MIBI动力学变化与大鼠缺血-再灌注心肌存活的相关性研究

目的探讨用99Tcm-甲氧基异丁基异腈(MIBI)动力学变化评价心肌存活的价值.方法15只离体Krebs-Henseleit(KH)液灌注的鼠心脏,随机分成3组对照组(5只),有葡萄糖的缺血-再灌注组(IR+G组,5只),无葡萄糖的缺血-再灌注组(IR-G组,5只).用含99Tcm-MIBI(14.8MBq)的KH液灌注,观察40min的摄取和清除.用肌酸激酶(CK)分析、氯化三苯四唑(TTC)染色和透射电镜(TEM)分析研究心肌损伤程度,用放射自显影(ARG)观察99Tcm-MIBI在心肌内的分布.结果99Tcm-MIBI的摄取[每克组织百分注射剂量率(%ID/g)]在IR+G组为(7.09±0.97)%ID/g,IR-G组为(6.64±0.68)%ID/g,对照组为(11.44±1.79)%ID/g,IR-G组与IR+G组相比摄取量差异无显著性(P＞0.05),IR-G组和IR+G组与对照组相比均显著降低(P＜0.05).IR-G组99m-MIBI清除分数为(72.75±9.89)%,远高于对照组[(20.68±1.92)%]和IR+G组[(21.03±3.68)%,P均＜0.05],对照组与IR+G组的差异无显著性.99Tcm-MIBI的40min清除末滞留率在IR-G组[(1.82±0.73)%ID/g]和IR+G组[(5.61±0.89)%ID/g]远小于对照组[(9.09±1.57)%ID/g,P＜0.05],IR-G组也远小于IR+G组(P＜0.001).CK分析、TFC染色和TEM分析证明IR-G组比IR+G组有更多的心肌损伤.通过TTC染色(r=0.84,P＜0.05)和CK分析(r=-0.97,P＜0.05)确定最终99Tcm-MIBI的活度与存活心肌量高度相关,通过ARG证实99Tcm-MIBI分布于鼠心肌细胞及间质内(光镜下).结论99Tcm-MIBI的清除对代谢状态敏感,可用于评价进行性心肌损伤.     

急性心肌梗死患者J波的临床研究

目的　研究心电图有 J波的急性心肌梗死 ( AMI)患者的临床情况。方法　选择住院的急性心肌梗死患者 10 2例 ,心电图有 J波者 5 0例为研究组 ,心电图无 J波者 5 2例为对照组 ,比较两组临床情况。结果　心电图有 J波组比心电图无 J波组发生胸闷 ( 3 0 /5 0∶ 2 0 /5 2 ,P<0 .0 5 )、前壁心肌梗死 ( 2 8/5 0∶ 18/5 2 ,P<0 .0 5 )、合并糖尿病 ( 14/5 0∶ 4/5 2 ,P<0 .0 5 )、超声心动图检查发生舒张功能减低 ( 2 4/5 0∶ 14/5 2 ,P<0 .0 5 )、心电图检查发现室性心动过速 ( 11/5 0∶ 1/5 1,P<0 .0 5 )者多。结论　心电图有 J波者比心电图无 J波者临床情况差 ,易于发生严重心律失常     

The accuracy of a fiberoptic oximeter over a wide range of arterial oxygen saturation values in piglets

A piglet model was used to evaluate the accuracy of a fiberoptic oximeter over a wide range of arterial oxygen saturation (SaO₂) values. In eight anaesthetized piglets, the inspired oxygen concentration was varied from 30% to 6% resulting in a SaO₂ range from 100% to 15%. Paired data of the Opticath® fiberoptic catheter, which was placed in the descending aorta, and blood sample SaO₂ values assessed by a multiwavelength oximeter, were analysed. After in vitro calibration according to the manufacturer's instruction, the fiberoptic catheter started to underestimate the SaO₂ below 78%, worsening towards lower SaO₂ values. The overall bias was -3. 4% and the precision 3. 8%. An off-line fit with a non-linear model resulted in a standard deviation of residuals of 2. 6%. After several in vivo calibration adjustments when the Fiberoptic oximeter deviated more than 4% from the blood sample value, the bias was eliminated over the total SaO₂ range and the precision was 3. 7%. The Opticath® fiberoptic oximeter could have an accuracy for the whole SaO₂ range between 15–100% close to the accuracy of the multiwavelength oximeter, when the fiberoptic oximeter is adapted for the underestimation below 78% SaO₂.     

Transcranial cerebral oximetry and carotid cavernous fistula occlusion

Summary Different methods have been used in the evaluation and monitoring of the cerebral oxygen supply during neuro-interventional therapies. Attenuation of near-infrared light by the chromophores oxyhemoglobin and deoxyhemoglobin have shown to be useful in the study of the cellular oxygen metabolism and oxygen delivery to the brain. Transcranial cerebral oximetry (TCCO) has the advantage of providing real-time information regarding regional brain oxygen saturation (rSO₂) by using wavelengths in the near-infrared range.We present a patient with a carotid cavernous fistula who underwent balloon occulusion and concurrent continuous TCCO monitoring. TCCO was found to be a useful tool providing immediate rSO₂ values during the angiographic and interventional procedures. Initial balloon occlusion of a carotid cavernous fistula resulted in partial occlusion of the internal carotid artery lumen causing an immediate decrease in rSO₂ which correlated with angiographic findings. Subsequent reocclusion of the fistula produced a slower and smaller degree of decrease in rSO₂ with clinical improvement in the patient. Changes in rSO₂ were detected before any adverse clinical event was observed. TCCO was reliable, safe, sensitive, and provided a real-time assessment tool for the monitoring of brain oxygen supply in a patient undergoing a neuroendovascular procedure.     

脉冲吸氧与脉冲吸氧仪

本文介绍了脉冲吸氧的机理和优越性以及脉冲吸氧仪的原理。脉冲吸氧可以增加吸氧效果,减少感染,大大降低氧耗量。     

Environmental effects on the growth and proteolysis of Treponema denticola ATCC 33520

The effect of pH, redox potential, O₂ and H₂ on the growth and proteolytic activity of Treponema denticola ATCC 33520 was studied in a chemostat at different growth rates. The peptidase and protease activities were estimated using different amido-methyl coumarin derivatives and azocasein. The maximum growth rate of T. denticola ATCC 33520 was 0.14 h⁻¹. Reduction of the growth rate of T. denticola by 50–60% gave: an increase in cell mass of 150–200%, a higher acetogenesis and a shift of the pH optimum. The protease and phenylalanine peptidase activities seemed to be of greater importance for the growth of T. denticola ATCC 33520 than the rather low arginine and proline peptidase activities. The redox potential (E_h) played a secondary role. At microaerophilic conditions with 1–5% O₂, the cultures maintained a redox potential below −311 mV and an optimal acetogenesis. The presence of H? induced a marked growth stimulation of T. denticola ATCC 33520. It is concluded that the cell mass and proteolytic activity of T. denticola ATCC 33520 are modulated by the growth rate and the pH and to a lesser extend by the redox potential and presence of O₂. Stagnation of the exudate-flow influences these factors and will lead to an increase of the spirochetal population and proteolysis in the periodontal pocket.     

Attenuation of myocardial injury due to oxygen free radicals(OFR) by pretreatment with OFR or calcitonin gene-related peptide

目的：研究氧自由基（ＯＦＲ）及降钙素基因相关肽（ＣＧＲＰ）预处置对ＯＦＲ所致离体大鼠心脏损伤的拮抗作用．方法：Ｌａｎｇｅｎｄｏｒｆ法灌流心脏，电解ＫＨ液产生ＯＦＲ．结果：ＣＧＲＰ或ＯＦＲ预处置减轻ＯＦＲ所致心脏收缩功能下降，冠脉流量减少和肌酸激酶（ＣＫ）释放增加．蛋白激酶Ｃ（ＰＫＣ）抑制剂Ｈ７可取消ＯＦＲ预处置的心脏保护作用（对照组，ＯＦＲ损伤组，ＯＦＲ预处置组，Ｈ７加ＯＦＲ预处置组及Ｈ７组的ＣＫ释放量分别是１１０±７，２１５±２３，１６９±１４，２４０±３０，１１３±１９Ｕ·Ｌ－１）．结论：ＯＦＲ或ＣＧＲＰ预处置对ＯＦＲ所致心肌损伤具有拮抗作用，该作用与ＰＫＣ激活有关．     

关胆囊结石的CT定量诊断

目的 评价第三代CT定量诊断胆囊结石的准确率及敏感性.方法 120例胆囊结石的病人在使用第三代CT检查后7天内施行胆囊切除手术,术后剖开胆囊,进行结石计数和最大结石的最大径线测量.结果 120例胆囊结石患者,其中87例有确切结石计数和测量结果（72.5%）;33例CT检查未发现胆囊结石（27.5%）.CT图像中显示的胆囊结石的数目：均数±标准差＝3±15个;范围为2～82个与手术发现的数目：均数±标准差＝68±316个;范围为2～1326个,两者比较具有显著性差异（P＜0.001）.CT图像发现的胆囊内最大结石的最大径线值：均数±标准差＝1.08±1.06cm,范围为0～2.4cm;与手术测量值均数±标准=1.68±0.14cm范围为0.67～3.1cm,两者比较有显著性差异（P＜0.001）.结论 用第三代CT进行胆囊结石的定量诊断不够准确,敏感性也有不足.     

医院PSA制氧系统购置及配置论证

PSA方式制氧是目前最先进的制氧方式，PSA制氧系统是各医院首选的供氧设备。本文阐述了PSA制氧的工作原理及购置理由，并就如何配置此系统进行了全面地论证。