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1.
目的制备一种新型的载脑源性神经营养因子(BDNF)脂质体纳米微粒脂膜微泡超声造影剂(BDNF-UMCA),并对其应用进行初步评价。方法以冷冻干燥法在"脂氟显"制备的基础上加入与二棕榈酰磷脂酰胆碱等量的含生物素化棕榈酰磷脂酰甘油钠-聚乙二醇2000-生物素,制备含生物素化脂膜超声微泡造影剂,通过链亲和素耦连含生物素化聚乙二醇载BDNF脂质体纳米微粒制备BDNF-UMCA,检测其物理性质、载药量、包封率、稳定性及体内声学特性。结果 BDNF-UMCA平均粒径(4.20±0.79)μm,浓度1.02×109/ml,总药物含量(1.18±1.96)mg/ml,包封率(71.6±2.6)%。在4℃下,BDNF-UMCA平均粒径和包封率各时间点无明显变化;在(24±2)℃下,BDNF-UMCA的平均粒径随时间推移逐渐增大,第1、3、5、7天的粒径与初始粒径比较差异均有统计学意义(均P0.05),包封率在(24±2)℃下各时间点比较差异无统计学意义。BDNF-UMCA能显著增强实验动物肝脏显影,平均峰值强度(21.5±3.5)d B,平均达峰时间(19.2±5.2)s。结论应用生物素-亲和素耦连可成功制备BDNF-UMCA;BDNF-UMCA可为靶向显影及药物通过血脑屏障释放提供工具。  相似文献   

2.
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   

3.
目的 制备载硫酸长春新碱的聚乳酸-乙醇酸-聚乙二醇共聚物(PLGA-PEG)超声微泡造影剂,观察微泡的一般特性及体内、外显影效果.方法 采用W/O/W复乳-溶剂挥干法制备超声微泡造影剂,正交实验设计获得最佳制备工艺,采用紫外分光光度法测定微泡的包封率和载药量,光学显微镜观察微泡形态,以马尔文激光粒径测量仪测定微泡造影剂的粒径、Zeta电位,并观察微泡在兔心腔的显影效果.结果 获得的微泡造影剂为球形,平均粒径约为1.27 μm,包封率为(37.63±0.61)%,Zeta电位为-24.88 mV,静脉注射载药微泡后,能增强兔心腔超声显影效果.结论 采用复乳-溶剂挥干法成功制备超声微泡造影剂,能增强体内外超声显影效果.  相似文献   

4.
目的制备载3PO脂质体-微泡复合物(3PO-LMC),观察其体外超声显影及控制释放能力。方法采用薄膜水化法制备载3PO纳米脂质体,机械振荡法制备生物素化普通微泡,将两者通过生物素-亲和素连接方式结合获得3PO-LMC。采用激光粒度仪测定载3PO脂质体的粒径及Zeta电位,高效液相色谱仪(HPLC)测定其包封率;采用库尔特分析仪测定3PO-LMC的粒径和浓度,荧光显微镜观察其表征,HPLC测定3PO-LMC的载药量;并在琼脂模型中检测微泡的体外超声显影效果;比较不同超声强度(0.35、0.7、1.0 MPa)及作用时间(10、30、60 s)下3PO-LMC的药物释放率。结果载3PO脂质体的粒径为(174.77±3.62)nm,Zeta电位为(-22.75±0.63)mV,包封率为(90.74±1.67)%。制备的3PO-LMC表现为普通微泡形态,荧光显微镜下可同时见红、绿色荧光,浓度为(0.86±0.06)×109/ml,粒径为(2.54±0.15)μm,3PO-LMC的载药量为(99.58±6.63)μg/108个复合物;普通微泡和3PO-LMC在体外琼脂模型中均能显示出良好的超声显影效果。在相同超声强度下,药物释放率随着超声作用时间延长而增加;在相同超声作用时间下,药物释放率随着超声强度的增加而增加;当超声强度为1.0 MPa、作用60 s时,3PO-LMC的药物释放率达到最高,为(90.93±1.79)%。结论成功制备了3PO-LMC,其不仅可在体外显示出良好的超声显影效果,在超声作用下还具有良好的药物释放能力。  相似文献   

5.
载10-羟基喜树碱脂质超声微泡的处方制备及一般特性研究   总被引:2,自引:1,他引:1  
目的 研究载10-羟基喜树碱(HCPT)脂质超声微泡的处方制备工艺,筛选出最佳处方制备载药微泡,研究微泡的一般特性及显影效果,并检测微泡的药物包封率和载药量.方法 以机械振荡法制备载HCPT脂质超声微泡;采用正交试验优选处方;采用紫外分光光度法和反相高效液相色谱法测定微泡的包封率和载药量;在光学显微镜下计数并观察微泡的外观和分布情况;以马尔文激光粒径测量仪测量微泡粒径大小和Zeta电位;观察并比较微泡经60Co射线灭菌前后其外观、形态、平均粒径和包封率的改变;并观察微泡在兔肝脏的增强显影效果.结果 以最佳处方制备的载10-羟基喜树碱(2 mg)微泡的药物包封率为86.70%,载药量为21.70%;浓度为(3.07±0.58)×109/ml,粒径范围为(1.10±0.20)μm,平均粒径为1.10 μm;Zeta电位为-(3.90±0.80)mV;超声定向辐照微泡后,药物吸光度值明显增加;经60Co射线灭菌后观察微泡形态、平均粒径及包封率无明显变化;静脉注射此载药微泡后,兔肝脏超声显影持续增强.结论 采用机械振荡法制备的载HCPT脂质微泡,包封率和载药量较高,粒径分布均匀,体内显影效果好,有望实现实时监控下的体内定点靶向给药,为进一步研究奠定了基础.  相似文献   

6.
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   

7.
机械振荡法制备脂膜超声造影剂的初步实验研究   总被引:8,自引:1,他引:8  
目的探讨机械振荡法制备脂膜超声造影剂的可行性,初步评价其制备效果。方法机械振荡仪系胶囊式调合器改装而成,造影剂制备后,用光镜观察微泡大小、形态,血球计数板测定微泡浓度,激光粒度分析仪测定粒径及分布、表面电位、pH值,在体实验观察造影剂对兔正常肝脏的增强效果。结果造影剂微泡的粒径均小于8μm,平均粒径为(1.67±0.11)μm,平均浓度为(2.56±0.15)×1010/ml,表面电位为(-37.5±0.3)mV,pH值为6.46±0.21,其对肝实质的增强持续时间达60min,而且重复性好。结论机械振荡法是制备脂膜超声造影剂的一种很有效的方法。  相似文献   

8.
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   

9.
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   

10.
目的 与全氟丙烷(C3F8)脂质微泡造影剂比较,分析自制液态氟碳(PFOB)脂质纳米粒体外显影及耐声压性的优劣。方法 分别制备生物素化PFOB脂质纳米粒及生物素化C3F8脂质微泡,评估其稳定性,并观察其加入亲和素前后的体外显影效果。对2种造影剂在低声压(MI=0.28)及高声压(MI=0.56)环境下进行超声辐照,于辐照前及辐照10、20、30 s后观察显影情况及其差异。结果 2种造影剂加入亲和素后均发生聚集现象,粒径均较加入亲和素前明显增大(P均<0.05);且加入亲和素前(t=16.225,P<0.001)、后2种造影剂间粒径差异均有统计学意义(t=-5.046,P<0.001)。稳定性观察期间PFOB脂质微粒内浓度无明显改变,而C3F8脂质微泡随放置时间延长浓度呈减低趋势。加入亲和素后,PFOB脂质纳米粒回声明显增强;C3F8脂质微泡加入亲和素前后显影效果均较好。低声压(MI=0.28)及高声压(MI=0.56)环境下,PFOB脂质纳米粒造影剂显影强度无明显改变,而C3F8脂质微泡显影强度随辐照时间延长呈减低趋势。结论 相较于C3F8脂质微泡,PFOB纳米脂质纳米粒造影剂粒径小、耐声压性好,更符合靶向超声造影剂的要求。  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.
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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   

18.
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   

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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