Question

请高手帮忙翻译下。。。。。不要翻译器哦~~~谢谢

Ultrasound pressure waves can map the location of lipid-stabilized gas micro-bubbles after their intravenous administration in the body, facilitating an estimate of vascular density and microvascular flow rate. Microbubbles are currently approved by the Food and Drug Administration as ultrasound contrast agents for visualizing opacification of the left ventricle in echocardiography. However, the interaction of ultrasound waves with intravenously-injected lipid-shelled particles, including both liposomes and microbubbles, is a far richer field. Particles can be designed for molecular imaging and loaded with drugs or genes; the mechanical and thermal properties of ultrasound can then effect localized drug release.In this Account, we provide an overview of the engineering of lipid-shelled microbubbles (typical diameter 1000−10000 nm) and liposomes (typical diameter 65−120 nm) for ultrasound-based applications in molecular imaging and drug delivery. The chemistries of the shell and core can be optimized to enhance stability, circulation persistence, drug loading and release, targeting to and fusion with the cell membrane, and therapeutic biological effects. To assess the biodistribution and pharmacokinetics of these particles, we incorporated positron emission tomography (PET) radioisotopes on the shell. The radionuclide 18F (half-life 2 h) was covalently coupled to a dipalmitoyl lipid, followed by integration of the labeled lipid into the shell, facilitating short-term analysis of particle pharmacokinetics and metabolism of the lipid molecule. Alternately, labeling a formed particle with 64Cu (half-life 12.7 h), after prior covalent incorporation of a copper-chelating moiety onto the lipid shell, permits pharmacokinetic study of particles over several days.Stability and persistence in circulation of both liposomes and microbubbles are enhanced by long acyl chains and a poly(ethylene glycol) coating. Vascular targeting has been demonstrated with both nano- and microdiameter particles. Targeting affinity of the microbubble can be modulated by burying the ligand within a polymer brush layer; the application of ultrasound then reveals the ligand, enabling specific targeting of only the insonified region.Microbubbles and liposomes require different strategies for both drug loading and release. Microbubble loading is inhibited by the gas core and enhanced by layer-by-layer construction or conjugation of drug-entrapped particles to the surface. Liposome loading is typically internal and is enhanced by drug-specific loading techniques. Drug release from a microbubble results from the oscillation of the gas core diameter produced by the sound wave, whereas that from a liposome is enhanced by heat produced from the local absorption of acoustic energy within the tissue microenvironment. Biological effects induced by ultrasound, such as changes in cell membrane and vascular permeability, can enhance drug delivery.

Answer 1

超声波可以定位出稳定脂质中的微小气泡，在这些物质（稳定脂质）被静脉注射到体内之后，便于估测血管密度和微血管流量。
微泡造影剂技术被食品及药品监督局批准，目前作为可视化左心室心率不齐的超声心动图的一种手段。
然而，超声波与静脉注射脂质粒子的反应，包括脂质体和微泡造影剂两者，是一个十分丰富的领域。粒子能被专门制作用于分子成象和装载药物或基因；超声波的机能和热能可以影响药物的局部释放。

在这个理念中，我们提出了一个脂质壳微气泡（一般直耐清袜径为1000-10000纳米）的工程概述和脂质体基于超声波的英语--分子影像和药物输送。脂质壳和核可以优化提高药物加载和释放过程中稳定性、与持续循环性,可以很好的与细胞膜融合并产生有治疗效果的生物反应。为了评估这些微粒在体内的分布与药物代谢，我们加入放射性同位素的外壳，这个外壳可以由正旦正电子发射断层扫描（PET）。在共价-18放射性核素（半衰期2小时）上加上一个(迪棕榈)血脂，使壳标记脂质在同化并昌激进入之后，促进短期分析药物代谢和脂质分子粒子代谢的生效。另外，标签上64Cu（半衰期12.7小时）后到前的脂质壳铜共价螯合基团，形成一个粒子，可以维持在数天的药代动力学粒子的研究。

长酰基链和聚乙二醇涂料同时加强了脂质体和微气泡的稳定性和持续循环性。
纳米微粒和微直径微粒都已经证实了血管的靶向。微气泡的血管靶向能被调制成具有涂层的聚合物并掩埋在向心附属体之下，进而利用超声波技术可以显示出向心配合价体，可具体作用于仅在声波穿透的地方。

微泡造影剂和脂质体载体需要不同的释放手段。微气泡加载（同位素）是由气体内核抑制的，并由多层结构或药物陷入颗粒表面的共轭来增强的。脂质体装载通常是装载于内部并由特殊药物的装载技术加强，从微气泡释放药物的这个结果是由于声波导致的气体内核内径的震动，这就是从一个脂质体中，由声波能量使组织微环境内产生热量，增强了局部吸收并使微气泡内直径共振的结果。超声波所导致的生物效应，如细胞膜和血管通透性的变化，可以加强药物的输送。尤其是作为微气泡振荡靠近血管壁，震波波或液体射流加强药物运输。超声波促使药物在注射前后轻微升温，有利于在血管组织间质运输的脂质体，从而增加在目标区域的药物积累。

终于搞完了，好累啊，你就自己再排版吧。>_<。@_@~

Answer 2

丫的，什么文章！这么多麻烦的词！还弄得我手机他妈卡半天！丫丫呸的！