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1.
目的以超声空化栓塞肿瘤微循环为目的,制备一种结合凝血酶原复合物(PCC)的超声造影剂,评价其理化性质。方法采用机械振荡整合法和表面吸附法分别制备结合PCC的负电荷脂膜超声造影剂(浮选法洗涤)。观察并检测洗涤前后微泡大小、形态、浓度、荧光亮度,微泡与PCC的结合率及Ⅸ因子的活性。结果结合PCC微泡的浓度、形态与普通微泡比较无明显差异,但易静置分层。微泡与PCC的结合率及Ⅸ因子活性:两种制备方法间比较无明显差异(P〉0.05),洗涤前与相同浓度的PCC比较Ⅸ因子活性无明显差异(P〉0.05),但洗涤后结合率均值由洗涤前的96%左右降为82%左右(P〈0.05),活性由90%左右降为19%左右(P〈0.01)。结论机械振荡整合法与表面吸附法均可制备结合PCC的超声造影剂,微泡与PCC结合率较高,洗涤前能保持Ⅸ因子较高的活性,两种方法间比较无明显差异。  相似文献   

2.
目的 探讨以与血管内皮生长因子(VEGF)的主要受体KDR特异性结合的短肽K237(P)为配体制备靶向脂质体超声造影剂(P-Bio-Av-Bio-Mbs)的方法。 方法 采用生物素-亲和素桥接法构建P-Bio-Av-Bio-Mbs,流式细胞术筛选最佳配体适配剂量,光镜及荧光显微镜观察靶向微泡与KDR强阳性表达的人大肠癌LOVO细胞结合情况,计算花环形成率。分别以5、50、99 ml/h速率水流冲刷,光镜观察靶向微泡与LOVO细胞结合情况。 结果 不同亲和素剂量下(0、2、6、10、30 μg),微泡表面亲和素携带率差异有统计学意义(P<0.05)。Mavidin=6 μg时,携带率增长达平台期;不同短肽剂量下(0、30、40、50、60、70、100 μg),微泡表面短肽携带率差异有统计学意义(P<0.05),当MK237=50 μg时,微泡表面短肽携带率增长达平台期。光镜下KDR强阳性表达的LOVO细胞周围花环形成率高达90.52%,荧光显微镜下微泡外壳发出明亮绿色荧光。随冲刷速度增加,靶细胞周围黏附的靶向微泡减少,在99 ml/h冲刷速度下,靶细胞周围仍可见花环结构。 结论 通过生物素-亲和素桥连作用,短肽K237被有效装配在P-Bio-Av-Bio-Mbs表面,体外具有靶向特异性及一定稳定性。流式细胞术是筛选靶向微泡配体适配剂量的可靠方法。  相似文献   

3.
目的 制备一种含生物素化脂膜的超声造影剂,并对其功能进行初步评价.方法 以冷冻干燥法在自制"脂氟显"(对照微泡)的基础上制备含生物素化脂膜超声造影剂微泡,检测其理化性质和造影功能,同时应用激光共聚焦显微镜和平行板流动腔法观察含生物素化脂膜微泡与链亲和素的黏附性.结果 ①含生物素化脂膜微泡造影剂在理化性质与小鼠肝脏造影显像方面能力与对照微泡比较差异无统计学意义(P〉0.05);②与异硫氰酸荧光素(FITC)标记的链亲和素孵育后,含生物素化脂膜微泡荧光检测呈阳性,对照微泡为阴性;③含生物素化脂膜微泡可结合于链亲和素包被的培养皿上,且随着链亲和素包被浓度的增加其结合稳定性也相应提高.结论 应用冷冻干燥法在制备"脂氟显"微泡造影剂的基础上,可成功制备含生物素化脂膜超声微泡造影剂,为今后制备靶向显影及载药(基因)超声造影剂奠定了基础.  相似文献   

4.
制备结合链酶亲和素超声造影剂的实验研究   总被引:1,自引:0,他引:1  
目的:探索制备一种结合链酶亲和素的脂膜超声微泡,以适用于亲和素-生物素法制备靶向超声造影剂,并评价其理化性质。方法:分4组于机械或超声振荡之前或之后,加入链酶亲和素完成超声造影剂的制备,采用浮选法洗涤。观察并检测洗涤前后各组微泡大小、形态、浓度、荧光亮度、微泡与链酶亲和素的结合情况。结果:机械或超声振荡制备的各组结合链酶亲和素的超声造影剂其浓度、形态与普通微泡比较无明显差异,但易静置分层。超声振荡法制备的微泡粒径稍大、浓度偏低。荧光显微镜观察:洗涤前各种不同方法所制备的微泡均能激发出明亮的红色荧光;洗涤后微泡浓度由1010左右降到107左右,微泡荧光亮度仍为“3级”。微泡与链酶亲和素的结合率,各种制备方法间比较差异无显著性意义(P>0.05),其结合率高达98%以上。结论:机械和超声振荡均可制备结合链酶亲和素的负电荷超声造影剂,微泡与其结合率高,为完成亲和素-生物素法制备靶向超声造影剂提供了重要基础。  相似文献   

5.
目的 采用自制的携E-选择素抗体的纳米级靶向超声造影剂对大鼠缺血再灌注损伤后的缺血心肌进行超声分子成像,评估其检测缺血心肌的可行性。方法 采用生物素-链亲和素方法制备纳米级靶向微泡,应用荧光显微镜及流式细胞仪检测微泡形态及抗体连接效率;将26只SD大鼠随机分为E-选择素靶向微泡组(MBE组,n=10)、IGg抗体微泡组(MBIGg组,n=10)、普通微泡组(MBC组,n=6),制备心肌缺血再灌注损伤模型,将冠状动脉左前降支阻断15 min后恢复灌注,于再灌注后6 h经尾静脉分别注射3种微泡行CEUS。后行病理学检查。结果 MBE组缺血区域声学强度(VI)显著高于非缺血区(P<0.05),也显著高于MBC组、MBIGg组缺血区域的VI(P<0.05);MBC组、MBIGg组缺血区域与非缺血区的VI差异无统计学意义(P>0.05)。结论 纳米级E-选择素靶向超声微泡可以早期检测到缺血心肌,有望实现缺血心肌的"记忆"成像。  相似文献   

6.
LHRHa靶向微泡造影剂的制备及体外寻靶实验   总被引:4,自引:2,他引:2  
目的 制备人卵巢癌靶向超声造影剂,观察其体外寻靶能力。方法 采用生物素-链霉亲和素法制备促黄体生成素释放激素类似物(LHRHa)靶向脂质微泡,以免疫荧光染色验证LHRHa与脂质微泡的结合情况,并以普通脂质微泡作为对照,在倒置显微镜下观察LHRHa靶向脂质微泡对人卵巢癌A2780/DDP的体外寻靶能力。结果 LHRHa靶向脂质微泡免疫荧光阳性;体外寻靶实验显示LHRHa靶向脂质微泡能够与表面存在LHRH受体的A2780/DDP细胞特异性结合,而普通脂质微泡则不能结合。结论 利用生物素-链霉亲和素方法可成功制备LHRHa靶向脂质微泡造影剂,该靶向造影剂具有体外寻靶能力。  相似文献   

7.
目的 探讨磁性超声微泡(MAMBs)的制备方法并检测其基本性质。方法 自制生物素化超声微泡,通过亲和素-生物素系统将超磁性纳米微粒连接于超声微泡表面,制备MAMBs。采用颗粒计数分析仪检测生物素化超声微泡及MAMBs的粒径及粒径分布。采用倒置系统显微镜观察MAMBs的形态及分散性。采用超声实时显影生物素化超声微泡及MAMBs,并于5 min内观察其运动情况。外置永磁铁5 min,超声实时观察MAMBs显影变化。结果 生物素化超声微泡及MAMBs平均粒径分别约(1.11±0.21)μm和(3.70±0.89)μm。显微镜下观察MAMBs形态规则,分布均匀,无黏附聚集。外置永磁铁前,生物素化超声微泡及MAMBs均表现为增强回声,并呈自下而上的上浮状态。外置永磁铁后,MAMBs向永磁铁方向做自上而下的定向移动并聚集。结论 MAMBs形态规则,分布较均匀,具有显著的超声显影效果,可被外置永磁铁吸附做定向移动和定位聚集,可能为超声诊疗中增加局部微泡浓度奠定了实验基础。  相似文献   

8.
目的制备血栓靶向脂膜超声造影剂,并对其配体结合率进行初步评价。方法通过生物素-抗生物素蛋白桥连法,制备携带血栓靶向配体的脂膜超声造影剂,非靶向脂膜微泡为对照;采用流式细胞仪初步评价靶向微泡配体结合率及其影响因素。结果靶向微泡荧光检测为阳性,对照组为阴性;流式细胞仪分析结果显示该血栓靶向微泡配体结合率达82.96%,对照组仅为0.92%、0.89%。结论采用生物素-抗生物素蛋白桥连接法,可以成功制备血栓靶向脂膜超声造影剂。微泡纯化过程中离心速度与离心时间对配体结合率的影响具有显著意义。  相似文献   

9.
平行板流动腔法评价生物素化脂质微泡制备效果   总被引:5,自引:1,他引:5  
目的 制备生物素化脂质微泡,并应用平行板流动腔检测流体切应力对生物素化脂质微泡与链亲和素结合稳定性的影响,为进一步开展超声分子成像研究奠定基础.方法 采用声振法制备出表面携有生物素分子的脂质微泡,与普通脂质微泡对照,应用平行板流动腔模型,设置不同流体剪切应力,观察与链亲和素靶向结合的生物素化微泡的黏附效果.结果 在不同浓度链亲和素包被的平行板流动腔中均见生物素化微泡结合;随着链亲和素包被浓度的提高,靶向结合的生物素化脂质微泡抗流体剪切应力能力明显提高.结论 应用平行板流动腔模型能成功检测生物素化微泡的靶向黏附效果,该模型可推广应用于其他靶向微泡制备成功后靶向黏附能力的体外检测.  相似文献   

10.
目的 探讨预定位技术提高超声造影剂靶向肿瘤细胞的能力。方法 采用两步法预定位技术靶向SKOV-3卵巢癌细胞:第一步加入生物素化的CEA抗体,第二步加入结合链霉亲和素的造影剂。结果 制备的结合链霉亲和素的PLGA造影剂平均粒径为(346.20±74.49)nm。链霉亲和素与造影剂的连接效率为(95.02±0.62)%。预定位靶向组细胞结合的造影剂明显多于其余各组。结论 预定位技术能提高造影剂的靶向性,可提高超声分子成像的敏感性。  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   

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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   

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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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