靶控输注异丙酚意识消失时血浆和效应室浓度的EC50与脑电双频谱指数的关系多中心大样本临床研究

目的 研究择期手术患者靶控输注（TCI）异丙酚意识消失时血浆、效应室靶浓度的50%患者意识消失时的药物浓度（EC50）与脑电双频谱指数（BIS）的关系。方法 5家医疗中心405例择期手术患者（国人）,ASAⅠ或Ⅱ级。靶控输注异丙酚,以血浆靶浓度1．2μg/ml为起点,到达预期血浆靶浓度后每30秒递增0．3μg/ml,直至患者意识消失。采用概率单位回归分析计算患者意识消失时异丙酚血浆靶浓度、效应室靶浓度的EC05、EC50和EC95及其所对应的BIS。结果 择期手术患者TCI异丙酚意识消失时异丙酚血浆靶浓度EC05、EC50和EC95分别是2．9μg/ml、3．8μg/ml和4．8μg/ml,效应室靶浓度EC05、EC50和EC95分别是1．3μg/ml、2．2μg/ml和3．2μg/ml,50%患者意识消失的BIS是58,5%和95%患者意识消失的BIS分别是77和40。结论 择期手术患者TCI异丙酚意识消失时血浆靶浓度和效应室靶浓度EC50及95%置信区间分别是3．8μg/ml（3．8～3．9μg/ml）和2．2μg/ml（2．2～2．3μg/ml）, 50%患者意识消失的BIS用95%置信区间是58（58～59）。     

不同治疗方法在急诊剖宫产恶心呕吐中的应用

目的观察不同治疗方法在急诊剖宫产术中恶心呕吐的应用。方法选择ASAI~II级104例急诊剖宫产手术患者,随机分为五组:指揉组(n=21)、恩丹西酮组(n=21)、甲氧氯普胺组(n=21)、氟哌利多组(n=21)和生理盐水组(n=20)。采用腰-硬联合阻滞麻醉,术毕实施术后镇痛(patient controlled epidural analge-sia,PCEA)。结果指揉组、恩丹西酮组与甲氧氯普胺组与氟哌利多组VAS评分基本相当,与生理盐水组比较(P>0.01),各实验组之间比较(P>0.05),表明指揉组、恩丹西酮组、甲氧氯普胺组和氟哌利多组疗效相同。结论指揉法在防治急诊剖宫产恶心呕吐中,简便易行,效果确切,副作用少,适用于术中轻度恶心呕吐;而甲氧氯普胺和恩丹西酮更适于程度较重的恶心呕吐;氟哌利多抗恶心呕吐的作用时间相对较长。     

老年腰椎间盘突出症的手术治疗

目的 探讨老年腰椎间盘突出症的特点与手术治疗效果.方法 对62例老人腰椎间盘突出症患者的临床与病理特点进行分析.均行腰椎后路椎板减压髓核摘除术,其中小切口开窗35例,半椎板切除20例,全椎板切除7例,根据手术前后JOA评分评价手术疗效.结果 老年腰椎间盘突出症病理以髓核组织的脱水,纤维环的破裂,小关节囊、周围韧带及软骨终板退变为主要特点.临床特点为下肢疼痛多发,腰部活动受限较多;双下肢神经系统检查肌力下降明显,生理反射改变明显.62例平均随访1.9年,JOA评分术后平均改善率为68.9%,手术前后JOA评分比较差异有显著性意义(P＜0.05).结论 老年腰椎间盘突出症患者病程长,体征多,病理改变明显,行腰椎后路椎板减压髓核摘除术,手术效果满意.     

Percutaneous hepatic venous isolation and extracorporeal charcoal hemoperfusion for high-dose intraarterial chemotherapy in patients with colorectal hepatic metastases

The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100–120 mg/m², using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5–15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia <2,000/mm³ in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intraarterial chemotherapy in patients with unresectable hepatic tumors.     

Autonomic dysregulation as a basis of cardiovascular, endocrine, and inflammatory disturbances associated with obstructive sleep apnea and other conditions of chronic hypoxia, hypercapnia, and acidosis

Obstructive sleep apnea has traditionally been viewed as a structural disease. A multitude of systemic endocrine and cardiovascular abnormalities have been previously attributed to the prevalence of obesity in these patients. A growing body of clinical evidence, however, points to a relationship between sleep apnea and its systemic abnormalities independent of obesity. We hypothesize that this association is based on a maladaptive autonomic response of chemoreceptors, reacting to the hypoxia, hypercapnia, and acidosis of sleep apnea. The elevated sympathetic response triggers an inflammatory cascade that results in a myriad of downstream consequences including insulin resistance, hypertension, diabetes, atherosclerosis and metabolic syndrome. The sympathetic bias and endocrine disturbances may further exacerbate sleep disturbance in a potentially pernicious cycle. Our proposal may extend to any chronic respiratory or metabolic conditions that manifest hypoxia, hypercapnia, and acidosis and elicit a maladaptive autonomic and inflammatory response.     

Rapid leukocyte integrin activation by chemokines

Summary: Chemokines control selective targeting of circulating leukocytes to the microvasculature by triggering inside-out signal transduction pathways leading to integrin-dependent adhesion. Integrin activation by chemokines is very rapid, is downmodulated within minutes and appears to involve both enhanced heterodimer lateral mobility on the plasma membrane, facilitating encounters with dispersed ligand, as well as induction of a high-affinity state. These two modalities of integrin activation by chemokines involve distinct signaling pathways in the cell, yet complement each other functionally, allowing binding of rolling cells under conditions of low as well as high ligand density. Recent data show that chemokines generate both pro- and anti-adhesive intracellular signaling events, whose equilibrium is likely to be relevant to the kinetics of adhesion and de-adhesion, and to cell movement during diapedesis and chemotaxis. Importantly, chemokines utilize different signaling mechanisms to modulate the activity of distinct integrin subtypes. These recent advances suggest that chemokines may regulate adhesive responses of immune cells based not only on patterns of chemokine receptor expression, but also on variable signaling pathways that can modulate the pro-adhesive responses of leukocytes as a function of their differentiated state, and of the local microenvironment.     

Map location of the kanamycin resistance determinant in P1Km0.

The kanamycin resistance determinant in P1Km lies between am33 and gene 2 on the P1 genetic map. This is within the invertible region (C loop) of P1 DNA.     

Multiple-bandwidth photoacoustic tomography

Photoacoustic tomography, also referred to as optoacoustic tomography, employs short laser pulses to generate ultrasonic waves in biological tissues. The reconstructed images can be characterized by the convolution of the structure of samples, the laser pulse and the impulse response of the ultrasonic transducer used for detection. Although the laser-induced ultrasonic waves cover a wide spectral range, a single transducer can receive only part of the spectrum because of its limited bandwidth. To systematically analyse this problem, we constructed a photoacoustic tomographic system that uses multiple ultrasonic transducers simultaneously, each at a different central frequency. The photoacoustic images associated with the different transducers were compared and analysed. The system was tested by imaging both mouse brains and phantom samples. The vascular vessels in the brain were revealed by all of the transducers, but the image resolutions differed. The higher frequency detectors provided better image resolution while the lower frequency detectors delineated the major structural traits with a higher signal-noise ratio.     

Committing embryonic stem cells to early endocrine pancreas in vitro

A panel of genetic markers was used to assess the in vitro commitment of murine embryonic stem (ES) cells toward the endoderm-derived pancreas and to distinguish insulin-expressing cells of this lineage from other lineages such as neuron, liver, and yolk sac. There are two nonallelic insulin genes in mice. Neuronal cells express only insulin II, whereas the pancreas expresses both insulin I and II. Yolk sac and fetal liver express predominately insulin II, small amounts of insulin I, and no glucagon. We found that ES-derived embryoid bodies cultured in the presence of stage-specific concentrations of monothio-glycerol and 15% fetal calf serum, followed by serum-free conditions, give rise to a population that expresses insulin I, insulin II, pdx-1 (a pancreas marker), and Sox17 (an endoderm marker). Immunohistochemical staining shows intracellular insulin particles, and its de novo production was confirmed by staining for C-peptide. Most, but not all, of the insulin+ or C-peptide+ cells coexpress glucagon, demonstrating a differentiation pathway to pancreas rather than yolk sac or fetal liver. Addition of beta-cell specification and differentiation factors activin beta B, nicotinamide, and exendin-4 to later-stage culture increased insulin-positive cells to 2.73% of the total population, compared with the control culture, which gave rise to less than 1% insulin-staining cells. These findings suggest that stepwise culture manipulations can direct ES cells to become early endocrine pancreas.     

心音信号的分形研究

本文通过引入分形概念,首次为描述心音信号的复杂程度给出了一个定量的指标——分数维数。研究结果表明:心音信号确实存在着“无标度区”,具有典型的分形特性;心音信号的分维值能显著性地区分正常心音、二尖瓣病变心音(包括二尖瓣狭窄、二尖瓣关闭不全及二尖瓣狭窄加关闭不全)和主动脉瓣病变心音(主动脉瓣狭窄、主动脉瓣关闭不全及主动脉瓣狭窄加关闭不全)。