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1.
对比超声检测肾血管内皮炎症的初步研究   总被引:1,自引:1,他引:0  
目的探讨对比超声检测肾缺血再灌注所致血管内皮炎症的可能性.方法采用缺血再灌注(I/R)方法制备兔肾血管内皮损伤的炎症模型,分别在I/R前后行静脉声学造影,通过定量分析判定对比超声检测肾血管内皮炎症的可能性.结果肾血管出现内皮炎症后,声学造影剂"排空"时间(8.00±1.36)min,较基础状态"排空"时间(4.25±0.35)min明显延迟,P<0.05.结论声学造影剂"排空"时间有可能是检测肾缺血再灌注损伤所致血管内皮炎症的个重要指标.  相似文献   

2.
目的用自制的靶向超声造影剂实现无创性地评价犬心肌缺血再灌注,同时研究其靶向性作用机制。方法将自行研制的表面活性剂超声造影剂“表活显”(surfactantfluorocarbon-filledmicrobubbles,SFCMB)与磷脂酰丝氨酸(phosphatidylserine,PS)结合,制备成靶向超声造影剂(SFCMB-PS),在实时心肌超声造影(MCE)条件下,用SFCMB-PS对犬心肌缺血再灌注模型进行延迟心肌显像。流式细胞术测定白细胞激活前和激活后与SFCMB-PS的结合情况以及在补体和β2整合素中的Mac-1缺乏时激活的白细胞与SFCMB-PS的结合情况。结果延迟心肌显像表明缺血再灌注区的造影剂回声较正常区的回声明显增强。流式细胞术证明了PS结合在造影剂微泡的表面,未激活的白细胞与微泡的结合率为(5.27±0.75)%,激活的白细胞与微泡的结合率为(39.67±6.83)%,结合率明显提高(P<0.01);补体和β2整合素中的Mac-1缺乏时,两者的结合明显受到抑制,结合率降到(12.27±1.66)%(P<0.01)和(10.90±2.40)%(P<0.01)。结论SFCMB-PS可以无创性地评价缺血再灌注损伤心肌的部位及其严重程度。SFCMB-PS是通过β2整合素中的Mac-1和补体介导途径与激活的白细胞结合并进入细胞内的。  相似文献   

3.
目前心肌声学造影 (myocardialcontrastechocardiography ,MCE)用于评价心肌血流灌注已成为研究的热点。近年来 ,已有多种声学造影剂经静脉注射评价心肌血流灌注 ,1992年美国研制Albunex声学造影剂由于微泡内含空气 ,其半衰期短 ,故不能经静脉达到心肌灌注目的 ,其后多种含氟烷气体的微泡造影剂问世 ,1998年美国研制的Optison应用于临床。本研究探讨应用自行研制以白蛋白、葡萄糖、甘露醇等按一定比例配置成溶液经声化产生含空气的微泡 ,我们称之为新型白蛋白微泡声学造影剂 ,经周围静…  相似文献   

4.
7条狗开胸后冠脉内和主动脉根郎注射不同剂量的H_2O_2、Vit C-NaHCO_3混合液、手振法和声振法76% Renografin 4种声学造影剂。结果:主动脉根部注射18/24次显影。冠脉内67/67次显影。结论:声学心肌造影是一安全可行技术。一次造影剂量以0.5ml为宜。微泡直径>12μm的造影剂有剂量依赖性心肌抑制作用,并引起心肌排空时间非生理性延长。直径<10μm微泡造影剂对心肌无抑制作用,且能反映心肌内造影剂真实排空时间。  相似文献   

5.
目的探讨简单有效的兔心肌缺血再灌注损伤模型制备方法,并利用心肌声学造影评价兔心肌缺血再灌注损伤。方法将70只日本大耳白兔随机分为2组:35只心肌缺血/再灌注组(I/R)和35只假手术组(SH)。I/R组阻断冠状动脉左前降支90min,再灌注60、120、180min及1周;SH组开胸后同一部位只穿线不阻断。观察两组兔术前及术后各时段心肌声学造影的变化,最后行HE及MASSON染色。结果成功制备兔心肌缺血再灌注损伤模型30只,I/R组缺血90min至再灌注180min兔损伤节段造影剂视频强度超声均值对比术前及SH组均有不同程度减低,且差异有统计学意义(P0.05)。I/R组兔术后HE及MASSON染色均证实有心肌损伤病理表现,随着早期再灌注时间的延长损伤程度逐渐加重。结论通过阻断兔冠状动脉左前降支90min后解除阻断使其再灌注可成功建立心肌缺血再灌注损伤模型,心肌声学造影可以有效评价心肌缺血再灌注损伤。  相似文献   

6.
目的用自制的靶向超声微泡造影剂,实现无创性地评价犬心肌缺血再灌注(I-R)的范围及严重程度.方法将本研究所自行研制的表面活性剂类超声造影剂--"表活显"表面,结合上磷脂酰丝氨酸(PS),制备成具有靶向性的造影剂(MB-PS),用MB-PS对犬I-R模型在实时心脏超声造影条件下进行延迟心肌显像,实验结束后,心肌经0.5%伊文思蓝(Evens)和1%氯化三苯四氮唑(TTC)染色,确定缺血及坏死心肌范围,并与延迟心脏超声造影显像结果比较其一致性.结果细胞流式术(FC)证明了PS结合在造影剂微泡的表面,延迟心肌显像表明缺血再灌注区的造影剂回声较正常区的回声明显增强,与病理染色结果基本一致.结论缺血损伤再灌注后,心肌缺血部位的造影剂回声较其余部位正常心肌的造影剂回声明显增强,正是因为 MB-PS聚集并停留在缺血-再灌注区,才使得超声可以发现微泡的回声,从而得以无创性地评价炎症发生的部位及其严重程度.  相似文献   

7.
目的 探讨心肌声学造影技术( myocardial contrast echocardiography,MCE)定量评价硝酸甘油对犬顿抑心肌微血管内皮功能延迟保护作用的价值。方法 1 2只健康成年杂种犬随机分成缺血再灌注组( A组)和硝酸甘油组( B组)。A组不给予任何药物,保持基础状态,单纯进行左冠状动脉前降支结扎2 0 min,再灌注1 2 0 min,分别于缺血及再灌注时弹丸式注射自制含氟碳气体的微泡声学造影剂进行MCE。B组用微量静脉泵以2 μg/ ( kg.min)速度静滴硝酸甘油1 h,2 4 h后结扎左冠状动脉前降支,其余步骤同A组。在不同观测时间点分别经主动脉根部注射乙酰胆碱( acetylcholine,ACH) 1 0 μg/ kg,于注射前和注射后4 0~5 0 s重复心肌声学造影。在ADT- INT状态下于左室乳头肌水平短轴切面测定左冠状动脉前降支供血区域的心肌层内心肌视频密度时间-强度曲线参数,每次实验结束后,将心肌组织进行伊文思蓝( Evans blue,EB )及红四氮唑( triphenyl tetrazolium chloride,TTC)心肌组织染色。结果 两组顿抑心肌的峰值声强度、时间-强度曲线下面积比正常心肌明显减低,差异有显著性,B组在再灌注即刻、3 0、6 0、90 min时峰值声强度及曲线下面积均高于A组,差异有显著性意义,B组比A组更快恢复至正常水平。再灌注后两组的ACH- PIR显著降低,B组  相似文献   

8.
犬缺血再灌注心肌靶向超声造影图像的组织定征量化研究   总被引:1,自引:0,他引:1  
目的用超声组织定征量化分析白细胞靶向超声造影剂对犬心肌缺血再灌注(ischemia-reperfusion,I-R)损伤声像图。方法将自制超声微泡造影剂"表活显"(self-madesurfactantfluorocarbon-filledmicrobubbles,SFCMB)与磷脂酰丝氨酸(phosphatidylserine,PS)结合,制备成白细胞靶向超声微泡造影剂(SFCMB-PS),在实时心脏超声造影条件下,用SFCMB-PS对9只犬心肌I-R模型进行延迟心肌显像。实验结束后,在心肌I-R损伤处取组织块立即进行髓过氧化物酶(myeloperoxidase,MPO)活性测定。超声组织定征定量分析缺血再灌注损伤心肌。结果I-R损伤心肌声像图的回声强度[(22.56±4.62)GS]明显增高,与正常心肌[(16.57±3.82)GS]和缺血心肌[(5.00±2.58)GS]比较,差异均有统计学意义(P<0.01),而且其与MPO活性有良好的相关关系(r=0.776,P<0.05)。结论超声组织定征定量分析缺血再灌注心肌靶向超声显像能够较准确、客观地反映再灌注损伤的严重程度。  相似文献   

9.
目的 制备同时携载P选择素和ICAM-1抗体的靶向超声微泡造影剂,以评估小鼠缺血再灌注损伤心肌声学造影显像效果.方法 采用生物素-亲和素方法制备靶向微泡,于激光共聚焦显微镜下观察微泡形态,流式细胞仪检测连接效率.将24只健康昆明小鼠随机分成3组:结合双抗体选择素微泡组(MBd组)10只、结合P选择素单抗组(MBp组)10只,空白微泡组(MBc组)4只.结扎冠状动脉左前降支近左主干分支,制作心肌缺血再灌注模型,60 min后经尾静脉分别注射MBd、MBp及MBc,采集心肌对比造影图像.所有图像均采用Sonomath超声影像分析仪处理.结果 MBd组和MBp组对缺氧内皮细胞的黏附力以及对缺血再灌注区心肌显像增强程度显著高于MBc组(P均<0.05),MBd组对缺血再灌注区心肌显像延迟时间高于MBp组(P<0.05).结论 双靶向微泡联合超声造影是检测和评估小鼠缺血再灌注心肌的无创性手段.  相似文献   

10.
心肌缺血再灌注发生后 ,白细胞可大量渗入心肌层使心肌细胞受损甚至坏死。本研究用于检测如下假说 :利用白细胞靶向声学造影剂进行心脏超声造影检查 ,可以对心肌缺血再灌注后心肌炎的发生范围及其程度进行良好评价。方法 :将磷脂酰丝氨酸 (phosphatidylserine ,PS)结合于脂质微泡外壳制成可与白细胞靶向结合的新型造影剂 (MB -PS)。将9只 3 0~ 3 5kg的实验犬开胸 ,先静脉注射Optison行心脏超声造影检查评估各动物心肌血流灌注情况 ,再将其中 6只犬的冠状动脉左前降支或左旋支钳夹 90min ,钳夹期间 ,再…  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
15.
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.  相似文献   

16.
17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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