血管回声跟踪技术评价兔腹主动脉早期动脉粥样硬化的实验研究

目的探讨血管回声跟踪技术评价兔高脂喂养不同阶段腹主动脉结构和弹性变化规律。方法把24只大耳白兔随机平均分成正常对照组(A组),高脂喂养4周组(B组)、8周组(C组)、12周组(D组),分别于高脂喂养4、8、12周末超声检测兔腹主动脉血管结构及弹性,各参数测值与对照组进行比较;超声检测和采静脉血后,将各组兔处死,取兔腹主动脉行病理学分析。结果B、C、D组总胆固醇、低密度胆固醇水平较对照组明显升高,高密度胆固醇较对照组明显降低(P<0.05)。C、D组腹主动脉弹性参数测值与A组比较差异有统计学意义(P<0.05或P<0.01)。常规超声扫查显示,A、B、C组兔腹主动脉内膜光滑,内中膜厚度正常、均匀,未见斑块回声;D组兔腹主动脉内膜不光滑、毛糙、回声增强,内中膜不均匀增厚,局部可见呈偏心状小斑块。光镜下观察:A、B组兔腹主动脉内皮细胞连续完整,内弹力膜连续,无分层,无断裂;C组兔腹主动脉内膜及内皮细胞增生,可见多层泡沫细胞突入管腔,内弹力膜可见部分中断;D组兔腹主动脉内皮细胞不连续性缺失,内弹力膜中断,平滑肌细胞向内膜增生,可见斑块突向管腔。结论兔动脉粥样硬化早期光镜下仅出现泡沫细胞时,血管硬度已出现异常,粥样斑块出现时血管硬度进行性增高,提示诊断早期动脉粥样硬化血管硬度参数比形态学指标更敏感。     

粥样硬化兔腹主动脉缩窄近端和远端内膜巨噬细胞与树突细胞的变化

目的观察粥样硬化兔腹主动脉缩窄近端和远端内膜巨噬细胞与树突细胞的变化。方法将同批兔随机分为高脂饲料组15只和普通饲料组10只,喂养28周后对高脂组10只、普通组5只手术结扎腹主动脉造成管腔缩窄,余普通组5只和高脂组5只给予假手术,术后分为高脂手术组,普通手术组,普通假手术组和高脂假手术组,继续喂养4周后对各组兔腹主动脉多处测量血压,取血管行免疫组化染色,观察随血压的变化,高脂手术组兔腹主动脉缩窄近端、远端内膜巨噬细胞和树突细胞的变化。结果(1)高脂饲料组(包括高脂手术组和高脂对照组)血三酰甘油和胆固醇均高于普通饲料组;(2)高脂手术组缩窄近端腹主动脉血压高于高脂假手术组近端,而缩窄远端血压则低于高脂假手术组;(3)普通对照组血管内膜薄而光滑;高脂组血管内膜有大量泡沫细胞堆积;高脂手术组腹主动脉缩窄近端内膜比高脂假手术组近端内膜厚,缩窄远端内膜比高脂假手术组远端内膜薄;(4)高脂手术组缩窄近端内膜巨噬细胞和树突细胞的数量均多于高脂假手术组近端,缩窄远端少于高脂假手术组远端。结论粥样硬化兔腹主动脉缩窄近端血压高,内膜厚,巨噬细胞和树突细胞数量多,推测斑块不稳定性增高;缩窄远端血压低,内膜薄,巨噬细胞和树突细胞数量少,推测斑块不稳定性降低。     

多沙唑嗪对兔血脂和血管内膜增生的影响

目的：探讨多沙唑嗪对兔动脉球囊损伤后血管狭窄的影响及与血脂的关系。方法：23只新西兰兔随机分为3组，正常对照组用普通饲料喂养并不予任何处理。另两组用高脂饲料喂养并行腹主动脉球囊损伤术，多沙唑嗪组术后应用多沙唑嗪控释片4mg／d灌胃，术后4周处死兔，观察各组血脂以及血管损伤处内膜、中膜厚度、新生内膜面积、管腔面积。结果：高脂喂养造成兔血脂明显增高。手术开始时多沙唑嗪组和球囊损伤组两组血脂水平无差异，手术4周后多沙唑嗪组总胆固醇较球囊损伤组降低，而高密度脂蛋白较球囊损伤组增高。术后多沙唑嗪组与球囊损伤组血管损伤处相比血管内膜增生减轻，新生内膜面积减少，管腔面积增加。结论：多沙唑嗪可以抑制高脂喂养加球囊损伤后兔腹主动脉血管的狭窄，可以降低血脂、抑制动脉粥样硬化进展。     

高同型半胱氨酸血症及其所致动脉粥样硬化动物模型的复制

背景：高同型半胱氨酸是动脉粥样硬化的危险因素之一,而血管拉伤后的新生内膜增生可能有助于动脉粥样硬化的形成。目的：研究采用高蛋氨酸饲料喂养结合球囊损伤腹主动脉的方法复制兔高同型半胱氨酸血症及其所致动脉粥样硬化模型的可行性。方法：将32只白兔随机分成4组：分别给予腹主动脉内膜球囊损伤和（或）2%L-蛋氨酸颗粒饲料,以正常饲养的兔作为对照。分别于实验的第0,2,12周采血化验,并于实验的第12周处死白兔取腹主动脉标本观察。结果与结论：给予2%L-蛋氨酸颗粒饲养2周后,兔血清高同型半胱氨酸水平明显增高（P〈0.05）,此时予腹主动脉内膜球囊损伤,12周后在兔损伤血管段形成了特有的动脉粥样硬化病变,并且同时给予腹主动脉内膜球囊损伤和2%L-蛋氨酸颗粒饲料的兔粥样斑块面积更大、内膜损伤更严重。说明采用蛋氨酸饲料喂养结合球囊损伤兔腹主动脉内膜的方法可在短时间内建立高同型半胱氨酸血症及动脉粥样硬化模型。     

声学造影评价兔腹主动脉粥样硬化的初步研究

目的探讨超声造影在动脉粥样硬化中的诊断价值.方法新西兰大白兔5只,高脂饮食喂养12周建立动脉粥样硬化模型.模型建立前后应用自制的脂膜氟碳声学造影剂"脂氟显"行腹主动脉超声造影.造影前后分别采用二维成像、视觉评分和视频密度法监测兔腹主动脉内膜、粥样斑超声成像特征并作定量分析.结果造影后血管内膜、粥样斑回声明显增强,视频密度较造影前明显增加.结论造影剂可提高血管内膜分辨率及粥样斑检出率,在动脉粥样硬化的早期诊断中有重要应用价值.     

间歇缺氧促动脉粥样硬化形成的兔模型观察

目的:探讨间歇缺氧对动脉粥样硬化形成的影响。方法:高脂饲料喂养兔,以间歇缺氧干预12周构造动物模型,普通饲料组为对照。比较腹主动脉病理学差异。结果:高脂间歇缺氧组血管内壁脂质沉积,镜下见内皮细胞脱落缺失,多层泡沫细胞堆积。其动脉粥样硬化分级(4.8±0.4)明显高于高脂饲养组(3.5±0.2,P<0.05)及对照组(1.1±0.3,P<0.01)。三组间脂纹脂斑面积与血管面积比亦存在明显差异(P<0.05)。结论:间歇缺氧可促进动脉粥样硬化形成。     

异基因间充质干细胞输注促进动脉粥样硬化发展

本研究探索间充质干细胞（MSC）输注对动脉粥样硬化的作用。通过体外培养兔骨髓穿刺液获得间充质干细胞。30只新西兰白兔随机分为3组：正常饮食组6只（对照）,给予普通饲料饲养;高脂饮食组12只,高胆固醇高脂饲料喂养后静脉注射生理盐水;MSC注射组12只,高胆固醇高脂饲料喂养后静脉注射5×10^7MSC。分别于实验前,实验第5周,第9周和第13周测体重和空腹血脂水平。实验第13周时处死所有动物,检测动脉粥样硬化斑块和主动脉外膜滋养血管。结果表明,MSC注射组与高脂饮食组相比,主动脉窦斑块面积显著增大（斑块面积占血管面积的百分比分别为（23．35±3．51）％和（11．39±3．08）％,P〈0．05）,整体主动脉斑块形成明显增多（斑块面积占主动脉面积的百分比分别为（76．64±12．70）％和（57．61±9．00）％,P〈0．05）。MSC注射组兔主动脉外膜滋养血管增生明显,毛细血管密度增加。结论：异基因MSC输注促进高脂血症兔动脉粥样硬化斑块进展。采用MSC或包含MSC的细胞进行细胞治疗时应采取策略,减少MSC促进斑块形成的作用。     

高脂饮食引起大鼠动脉血管内皮细胞衰老

目的:研究高脂饮食对大鼠血管内皮细胞衰老的影响。方法:大鼠高脂饲料喂养12周后测定血脂的变化,HE染色分析胸主动脉和肾动脉血管结构的改变;胶原酶灌注方法分离胸主动脉和肾动脉血管内皮细胞,应用免疫细胞化学的方法鉴定内皮细胞;应用细胞化学染色的方法检测衰老相关的半乳糖甘酶(senescence-associated β-galactosidase,SA-β-gal)活性。结果:SD雄性大鼠高脂饲料喂养12周后,大鼠血浆三酰甘油、总胆固醇、高密度脂蛋白胆固醇水平明显升高,胸主动脉和肾动脉出现明显的粥样硬化改变;胸主动脉和肾动脉血管内皮细胞SA-β-gal活性明显增加,表现为较强的β-gal染色。结论:高脂饮食引起大鼠胸主动脉和肾动脉粥样硬化改变,动脉血管内皮细胞衰老增加。     

超声检查和血管造影对兔动脉粥样硬化狭窄模型的评价

目的:复制动脉粥样硬化狭窄的模型,比较超声和血管造影测量动脉狭窄程度的一致性。方法:实验于2003-02/05在河南省人民医院心血管内科实验室完成。选择雄性4月龄新西兰大白兔10只,分笼饲养,饲喂正常的全价颗粒饲料,自由饮水,观察1周后进入实验。1周后开始高脂饲料(含1.5%胆固醇)喂养,高脂喂养3d后用股动脉穿刺法行腹主动脉内皮剥脱术。术后继续喂养同样的高脂饲料。于术后第9周行腹主动脉超声和血管造影检查,记录腹主动脉狭窄程度。结果:纳入动物10只,均进入结果分析。①超声检查:术后第9周均可见腹主动脉有不同程度的粥样硬化斑块和狭窄,测量狭窄程度在46%～68%[(53.970±6.136)%],狭窄长度在6～20mm。②血管造影:术后第9周显示所有兔的动脉粥样硬化狭窄均形成,目测狭窄程度在50%～70%[(57.000±7.888)%],狭窄长度8～23mm。内皮剥脱术后第9周腹主动脉超声检查与血管造影检查的狭窄程度比较差异无显著性(P>0.05)。结论:动脉内膜剥脱术同时饲喂高胆固醇饮食可以在短时间内复制出动脉粥样硬化狭窄模型,超声和血管造影均能准确判定血管狭窄程度。     

应用重组改良型人膜联蛋白评估兔动脉粥样硬化病变程度的实验研究

目的：探讨99mTc标记的重组改良型人膜联蛋白（H-Annexin V）评估兔动脉粥样硬化病变程度的价值。方法：9只雄性大耳白兔随机分为球囊损伤组、单纯高脂饲料组、正常对照组,每组3只。球囊损伤组兔通过球囊损伤腹主动脉内膜,并饲喂高脂饲料15周。单纯高脂饲料组兔饲喂高脂饲料15周。对照组兔给予普通饲料喂养15周。15周后3组大白兔均自耳缘静脉注射99mTc-H-Annexin V 37~55.5MBq/kg,进行活体及离体血管显像。对球囊损伤组和高脂饲料组兔降主动脉分段,测定各段质量和放射性计数,并进行病理学检查。结果：显像剂注射后2小时,球囊损伤组兔降主动脉显影最为清晰。单纯高脂饲料组兔仍可见降主动脉影像。对照组兔降主动脉显影不明显。注射显像剂后2小时球囊损伤组靶/非靶（T/NT）比值（2.68±0.25）明显高于单纯高脂饲料组（2.08±0.18,t=3.26,P＜0.05）和正常对照组（1.57±0.24,t=5.44,P＜0.01）。离体显像可见：球囊损伤组影像较为清晰,而单纯高脂饲料组可见降主动脉显影,但影像欠清晰。球囊损伤组含AS斑块的血管片段放射性摄取为63.33±14.11cpm/mg,明显高于单纯高脂饲料组含AS斑块血管片段的放射性摄取52.08±12.39cpm/mg（t=2.17,P＜0.05）。结论：99mTc-H-Annexin V核素显像在评估兔动脉粥样硬化病变程度方面具有重要的临床价值。     

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.     

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.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.     

Evidence-Based Pain Management and Palliative Care in Issue Four for 2009 of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.     

Wie zuverlässig sind Angaben zu nichtentzündlichen ausgedehnten Schmerzen?

ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.