槲皮素对急性肺损伤大鼠P-选择素的影响

目的探讨槲皮素 (quercetin)对内毒素急性肺损伤 (ALI)大鼠P 选择素的影响。方法 :应用脂多糖 (LPS ,6mg/kg ,iv)复制大鼠ALI模型。选用SD大鼠 2 4只 ,随机分成盐水对照组、内毒素组、槲皮素干预组。各组大鼠均于注射LPS或生理盐水 6h后放血处死 ,然后观察肺病理改变、肺湿 /干重比 (W /D)值及动脉血氧分压 (PaO2 )、值 ,放射免疫法测定血清和肺组织匀浆P 选择素浓度。结果 :注射LPS 6h后 ,W /D、肺组织匀浆MPO、血清和肺组织匀浆P 选择素含量均有显著升高 (P 0 .0 1) ,PaO2 显著降低 ;而预先给予槲皮素可显著缓解上述变化 (P 0 .0 1或P 0 .0 5 ) ,肺组织病理改变明显减轻。结论 :槲皮素能改善大鼠ALI时气体交换功能 ,抑制P 选择素的释放 ,对内毒素诱导的ALI有保护作用。     

降钙素基因相关肽对内毒素急性肺损伤的保护作用

目的:探讨降钙素基因相关肽(CGRP),对内毒素急性肺损伤(ALI)的保护作用.方法:应用内毒素(LPS,6 mg/kg,iv)复制大鼠ALI模型.选用SD大鼠24只,随机分成盐水对照组(NS,n=8)、ALI模型组(LPS,n=8)、CGRP干预组(n=8).CGRP干预组按2μg/kg经腹腔注入CGRP,30 min后再经颈静脉注入LPS;LPS组以生理盐水代替CGRP;NS组中,CGRP和LPS均以等量生理盐水代替.各组大鼠均于注射LPS或生理盐水6 h后测定动脉血氧分压(PaO2)、血清肿瘤坏死因子(TNF-α)及白介素-8(IL-8)含量,随后处死动物,观察肺病理改变,测定肺湿/干重比(W/D)及肺组织匀浆髓过氧化物酶(MPO)浓度.结果:注射LPS 6 h后,W/D、肺组织匀浆MPO、血清TNF-α、IL-8含量较对照组均有显著升高(P＜0.01),PaO2显著降低;而预先给予CGRP(2μg/kg)干预可显著缓解上述变化,PaO2改善,MPO含量较ALI模型组降低(P＜0.05),肺组织病理改变明显减轻.结论:小剂量CGRP能改善大鼠ALI时气体交换功能,抑制炎症介质的释放,对内毒素诱导的ALI有保护作用.     

纳洛酮对心肺复苏后犬肺组织炎症因子水平及其mRNA表达的影响

目的　检测犬心肺复苏后 6h ,肺组织TNF α、IL 6浓度和肺中TNF αmRNA、IL 6mRNA、IL 10 mRNA的表达变化 ,以探讨纳洛酮对肺组织中TNF α、IL 6、IL 10含量的影响。方法　 18只健康杂种犬 ,随机分成 3组 ,空白组 (n =6 ) :不诱发室颤 ,6h后取肺组织 ;对照组 (n =6 ) :心跳骤停后予常规心肺复苏术 ,实验组 (n =6 ) :心跳骤停后予常规心肺复苏术 纳洛酮。于复苏后 6h取肺组织行TNF α、IL 6浓度和肺TNF α;mRNA、IL 6mRNA、IL 10mRNA的表达的测定以及行肺形态学检查。结果　实验组TNF α浓度明显低于对照组 (P <0 0 1) ,实验组、对照组、空白组IL 6浓度无差别 (P >0 0 5 )。实验组IL 10mRNA的表达明显高于对照组 (P <0 0 5 ) ,实验组和对照组的TNF αmRNA、IL 6mRNA的表达无差别 (P >0 0 5 )。实验组肺组织的病理损害低于对照组。结论　纳洛酮可减轻心跳骤停后肺组织的TNF α的生成 ,使IL 10mRNA的表达增加 ,从而减轻心肺复苏后肺的再灌流损伤。     

慢性阻塞性肺疾病气管炎症与细胞因子水平变化的研究

目的　探讨慢性阻塞性肺疾病 (COPD)气管炎症与细胞因子水平的变化规律。方法　测定 90例COPD患者急性加重期和缓解期及 30例健康人痰中白介素 8(IL 8)、肿瘤坏死因子 α(TNF α)、中性粒细胞髓过氧化物酶 (MPO)水平。结果　COPD患者急性加重期痰中IL 8、TNF α、MPO水平显著高于缓解期(P <0 .0 1) ;缓解期显著高于健康对照组 (P <0 .0 1)。结论　IL 8、TNF α、MPO作为主要的炎性递质参与了气管炎症的全过程。     

大鼠重症急性胰腺炎时急性肺损伤的实验研究

目的　研究内毒素 (endotoxin ,ET)、细胞因子 (cytokine,CK)、氧自由基 (oxygenfreeradi cals ,OFR)等在重症急性胰腺炎 (severeacutepancreatitis,SAP)时急性肺损伤 (acutelunginjury ,ALI)发病机制中的作用。方法　采用胰管逆行注射 1 5 %去氧胆酸钠制成大鼠重症急性胰腺炎时ALI模型。选用纯雄性健康Wistar大鼠共 4 0只 ,体重 2 2 0～ 2 5 0g,随机分成两组 :假手术对照组 (Sham ,n =10 ) ;SAP模型组(SAP ,n =30 ) ,分别于造模后 2 4h活杀。测定动脉血气 ,血清淀粉酶的含量 ,血清内毒素及血清和肺组织匀浆中的TNF α、IL 6、MDA、SOD的含量 ,肺湿 /干系数以及肺组织病理学改变。结果　SAP组血清内毒素 ,血淀粉酶 ,血清及肺组织匀浆中TNF α、IL 6、OFR均较Sham组明显升高 (P <0 0 1) ;动脉血气显示肺损伤严重 ,肺湿 /干比值较Sham组明显升高 ,肺通透性明显升高 ,肺病理学形态改变加重。结论　ET、TNF、IL 6、OFR在SAP时ALI发生发展中起了重要作用     

全氟化碳腹腔注射对内毒素致急性肺损伤大鼠预防作用的实验研究

目的 观察腹腔注射全氟化碳(PFC)对内毒素致急性肺损伤(ALI)的预防作用.方法 63只雄性健康Wistar大鼠随机分为空白对照组(NC组,9只)、内毒素脂多糖(LPS)致伤组(LPS组,27只)和8碳PFC(C8F18)预防组(预防组,27只).NC组腹腔注射质量分数为2%的戊巴比妥(40 mg/kg)麻醉后2 h处死;LPS组与预防组分别于实验前48 h腹腔注射生理盐水(15 ml/kg)或C8F18(15 ml/kg),实验当日腹腔注射2%戊巴比妥后静脉注射LPS 7 mg/kg,于2、4和6 h分批处死大鼠.比较3组各时间点动脉血氧分压(PaO2)、肺组织病理损伤评分、肺系数(右肺湿重/体重)、血液和支气管肺泡灌洗液(BALF)中肿瘤坏死因子-α(TNF-α)浓度.结果 LPS组和预防组PaO2均明显低于NC组(P均＜0.05);LPS组致伤后2、4和6 h PaO2与预防组同期比较差异均无统计学意义(P均＞0.05).LPS组肺组织病理学改变主要为肺泡间隔增宽,大量白细胞渗出、聚集,部分肺泡萎陷不张,腔中可见渗出液、出血;与LPS组比较,预防组肺组织病理变化无明显改善;病理损伤评分也无明显降低.LPS组与预防组血液和BALF中TNF-α的浓度均显著高于NC组(P均＜0.01);与LPS组比较,预防组血清TNF-α浓度在2、4和6 h无明显改变,BALF中TNF-α浓度在6 h时明显低于LPS组(P＜0.05).结论 腹腔注射C8F18原液15 ml/kg不能有效改善LPS所致ALI的PaO2下降及肺组织病理损伤,但对肺内TNF-α释放具有一定的抑制作用.     

己酮可可碱对大鼠内毒素性急性肺损伤iNOS和NO的影响

目的 :探讨己酮可可碱 (PTX)对大鼠内毒素性急性肺损伤 (ALI)iNOS和NO的影响。方法 :采用大鼠内毒素ALI模型。 2 4只SD大鼠随机分为生理盐水对照组 (CON)、内毒素组 (LPS)和PTX组 ,每组 8只。观察PTX对氧合指数 (PaO2 /FiO2 )、支气管肺泡灌洗液 (BAL)中蛋白含量、肺组织iNOS、NO3- /NO2 - 、髓过氧化物酶 (MPO)活性的影响 ,计算肺湿 /干比值(W /D)并行肺组织病理学检查。结果 :PTX组自 2h起各时间点PaO2 /FiO2 均高于LPS组 (P <0 0 5 ) ,W /D、BAL中蛋白含量、肺组织iNOS、NO含量和MPO活性均较LPS组显著降低 (P <0 0 5 )。病理学检查显示PTX组肺组织损伤程度较LPS组减轻。结论 :PTX对内毒素性ALI的保护作用可能与其抑制肺组织iNOS活性和减少NO生成有关。     

联合应用纳洛酮与甲基强的松龙对大鼠急性肺损伤的保护作用

目的　探讨联合应用甲基强的松龙、纳洛酮对内毒素所致急性肺损伤大鼠的防治作用及可能机制。方法　建立大鼠内毒素吸入性ALI模型 (LPS ,3mg/kg气管内注射 ) ,85只大鼠随机分为生理盐水对照组、内毒素损伤组、甲基强的松龙组 (内毒素 甲基强的松龙 )、纳洛酮组 (内毒素 纳洛酮 )、联合用药组 (内毒素 甲基强的松龙 纳洛酮 )。采用放射免疫方法检测大鼠血清TNF -α、IL - 8水平 ,并观察动脉血气分析及肺组织病理变化。结果　内毒素损伤组较生理盐水组TNF -α、IL - 8水平明显增高 ,动脉血氧分压明显降低 ,肺组织可见肿胀、淤血、炎细胞浸润。联合用药组各项指标较内毒素损伤组均轻。结论　联合应用甲基强的松龙和纳洛酮可降低气管内注入内毒素致大鼠ALI血清TNF -α、IL - 8升高水平 ,减轻肺损伤病理改变程度 ,对大鼠ALI有防治作用     

白细胞介素-10对急性肺损伤炎症/抗炎介质表达的影响

目的探讨白细胞介素-10(IL—10)对急性肺损伤(ALI)大鼠炎症介质／抗炎介质表达的影响。方法向气道内滴注内毒素(LPS，10mg／kg)建立大鼠ALI模型。54只雄性SD大鼠随机分为对照组、LPS损伤组、LPS加IL-10组，每组18只，各组又分为2、6和24h3个亚组，每个亚组各6只。按各时间点观察大鼠动脉血氧分压(PaO2)、支气管肺泡灌洗液(BALF)中细胞总数及分类计数、肺系数、BALF总蛋白水平及肺病理，同时用逆转录-聚合酶链反应(RT—PCR)方法检测肺组织中炎症介质／抗炎介质的表达。结果①LPS损伤组大鼠PaO2呈进行性降低；肺系数、BALF总蛋白水平及BALF中细胞总数均明显增加，分类以中性粒细胞为主；肺病理示肺内中性粒细胞大量浸润，伴出血、透明膜形成。LPS加IL-10组的各项指标均较LPS损伤组减轻。②LPS损伤组肺组织肿瘤坏死因子-α(TNF—α)mRNA表达于2h达高峰，随后迅速下降；白细胞介素-1β(IL—1β)mRNA表达于2h显著升高，6h达高峰，随后迅速下降；IL-1受体拮抗剂(IL—1ra)mRNA表达6h开始升高，且为峰值。24h仍高于对照组。LPS加IL-10组肺组织TNF—αmRNA、IL-1βmRNA表达受抑，而IL—1ra mRNA表达不受影响。结论①ALI早期TNF—αmRNA、IL-1βmRNA表达明显增加，而IL—1ra mRNA表达滞后，提示在无外来干预情况下，ALI早期存在炎症介质／抗炎介质的失衡。②IL-10可明显抑制炎症介质表达，不影响抗炎介质表达，有利于重建炎症介质／抗炎介质平衡，减轻LPS所致ALI。     

卡托普利对急性肺损伤大鼠肺气体交换的影响

目的:探讨卡托普利对急性肺损伤(ALI)大鼠肺气体交换的影响。方法:36只Wistar大鼠随机平均分成对照组、烟雾致伤组(ALI组)和卡托普利干预组(CAP组)。CAP组腹腔注射卡托普利(5mg/kg),对照组和ALI组腹腔注射等量生理盐水。15min后复制烟雾吸入性ALI模型。致伤后5min、5h分别采动脉血行血气分析,光镜观察肺病理变化。结果:ALI组血氧分压(PaO2)、动脉血氧饱和度(SaO2)及氧合指数(PaO2/FiO2)呈进行性下降,与对照组相比差异有显著性(P<0.01),肺病理改变明显。CAP组致伤后5hPaO2及PaO2/FiO2较5min显著改善(P<0.01),与ALI组相比差异有显著性(P<0.01),肺病理改变较轻。结论:卡托普利能明显改善ALI时肺的气体交换。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.