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1.
实验性急性肺损伤部分液体通气效应与剂量的关系   总被引:1,自引:0,他引:1  
目的:对肺灌洗诱导的急性肺损伤家兔实施不同剂量氟碳(perfluorocarbon,PFC)的部分液体通气(partialliquidventilation,PLV),观察其疗效及剂量-效应关系。方法:14只成年健康家兔,麻醉后经气管导管用生理盐水反复肺内灌洗,直至动脉氧分压(PaO2)<13 33kPa(100mmHg)达1h,记录肺气体交换、血液动力学及呼吸动力各参数作为肺损伤(acutelunginjury,ALI)基础值。随机分为PLV组及对照组,对照组以呼吸机行常规机械通气,不给予任何治疗措施;PLV组动物于ALI后每30min气管内灌入PFC(FC3280,3M,德国)6mL·kg-1共3次,总量为18mL·kg-1。以上述呼吸参数行机械通气。最后一次灌注后继续行机械通气3h,每小时记录各参数次。结果:PLV组PaO2及动脉血氧饱和度(HbO2)在灌注第一个剂量的PFC后即显著改善,并与剂量呈相关性;PaCO2在灌注第一个PFC剂量后较ALI时显著降低,但并不随剂量的增加而继续降低。结论:以氟碳为媒介的部分液体通气可明显改善肺灌洗诱导的急性肺损伤家兔的肺氧合,并呈剂量相关性,同时呼吸动力的改善与剂量无关。  相似文献   
2.
Abdominal wall defect caused by surgical trauma, congenital rupture, or tumor resection may result in hernia formation or even death. Tension-free abdominal wall defect repair by using patches is the gold standard to solve such problems. However, adhesions following patch implantation remain one of the most challenging issues in surgical practice. The development of new kinds of barriers is key to addressing peritoneal adhesions and repairing abdominal wall defects. It is already well recognized that ideal barrier materials need to have good resistance to nonspecific protein adsorption, cell adhesion, and bacterial colonization for preventing the initial development of adhesion. Herein, electrospun poly(4-hydroxybutyrate) (P4HB) membranes infused with perfluorocarbon oil are used as physical barriers. The oil-infused P4HB membranes can greatly prevent protein attachment and reduce blood cell adhesion in vitro. It is further shown that the perfluorocarbon oil-infused P4HB membranes can reduce bacterial colonization. The in vivo study reveals that perfluoro(decahydronaphthalene)-infused P4HB membranes can significantly prevent peritoneal adhesions in the classic abdominal wall defects’ model and accelerate defect repair, as evidenced by gross examination and histological evaluation. This work provides a safe fluorinated lubricant-impregnated P4HB physical barrier to inhibit the formation of postoperative peritoneal adhesions and efficiently repair soft-tissue defects.  相似文献   
3.
洪梅  沈明贵  蔡春 《应用化学》2010,27(3):280-284
制备了全氟辛基磺酰亚胺盐(M[N(SO2C8F17)2]n,n:3,4),并用于催化氟两相烷基化反应。考察了催化剂种类、反应时间、反应温度和催化剂用量对烷基化反应的影响,同时探讨了Yb[N(SO2C8F17)2]3对烷基化试剂摩尔比为0.2%时,催化烷基化试剂与不同芳烃的反应,表明Yb[N(SO2C8F17)2]3是一种有效的烷基化催化剂。含有催化剂的氟相通过简单的相分离后,可回收利用。氟相重复使用5次,其催化活性降低不大。  相似文献   
4.
This study investigates the dissolution behavior of oxide layers containing radionuclides using perfluorocarbon (PFC) emulsion as a reusable medium. Chemicals such as PFC, anionic surfactant, and H2SO4 are used for preparing the PFC emulsion, and emulsified using an ultrasonication process. The FTIR results show O–H stretching that is formed by the interaction of the carboxyl group of the anionic surfactant with the hydroxyl group of water containing H2SO4, and find that the H2SO4 can be homogeneously dispersed in the PFC–anionic surfactant–H2SO4 emulsion. The dissolution test of the simulated Cr2O3 specimen is conducted using PFC emulsion containing KMnO4. Through the weight losses of specimens and Scanning Electron Microscope-Energy Dispersive X-ray Spectrometer (SEM-EDS) analysis, it is confirmed that the Cr2O3 layer on the SUS304 specimen is easily dissolved using PFC emulsion. During the dissolution of the Cr2O3, it is observed that the dispersed H2SO4–KMnO4 became unstable and separated from PFC emulsion. Based on these results, the behavior of the PFC emulsion during the dissolution of the oxide layer is explained.  相似文献   
5.
关于烯烃和炔烃用自由基或离子型催化剂引发的共聚反应,迄今尚未见报道,可能由于单体活性相差悬殊的缘故。但用过渡金属催化时,则可发生共聚,例如,乙烯、丙烯和乙炔可在VOCl_3-(C_6H_(13))_3A1/烷烃溶剂催化下共聚成弹性体~([1])。又如全氟丙烯和全氟丁炔-2不能在氟离子催化下共聚~([2]),可是应用了π-二苯铬(O)催化剂~([3])却能成功地将这两种单体共聚为液体、蜡状物和固体,后两者的比例视所用单体的克分子比而异,即全氟丙烯比例高时,蜡状物比例高;反之,固体比例高。值得指出的是,据我们所知,这是在氟碳化合物中首次发现的烯-炔共聚的例子.  相似文献   
6.
氟两相体系实现了均相催化多相化, 可以方便地分离溶解在PFC 中的催化剂。本文综述了氟两相体系及氟合成领域, 包括氟溶配体、催化剂和反应物等方面的最新进展。对氟两相体系在烯烃的氢甲酰化反应、硼氢化反应以及其它有机反应中的广泛应用作了讨论。  相似文献   
7.
部分液体通气结合吸入NO对实验性急性肺损伤的疗效   总被引:1,自引:0,他引:1  
目的:评价以氟碳(PFC)为媒介的部分液体通气(PLV)结合吸入NO对急性肺损伤(ALI)动物肺气体交换和血液动力学的影响。方法:16只2 5~30kg的雌性健康家猪在麻醉后经气管导管以生理盐水反复肺内灌洗,直到动脉氧分压(PaO2 ) <13 3kPa达1h ,成为急性肺损伤模型,随机分为PLV组和对照组。对照组行常规机械通气2h ;PLV组经气管导管内灌以30mL/kgPFC(FC -77) ,2h后吸入体积分数为10 - 5NO观察30min ,然后停止吸入NO观察30min。记录不同时段肺气体交换和血液动力学参数。结果:PLV组PFC治疗1h ,动脉氧分压(PaO2 )与ALI时比较显著升高(P <0 0 5 ) ,平均肺动脉压(MPAP)显著升高(P <0 0 5 ) ;吸入NO与停止吸入NO比较,PaO2 无显著性升高(P >0 0 5 ) ,同时,Qs/Qt和MPAP亦无显著性降低(P >0 0 5 )。结论:PLV结合吸入NO与单独PLV比较,不能进一步降低急性肺损伤动物的肺动脉高压和肺内分流,亦不能有效增加氧合  相似文献   
8.
Novel polysiloxane material modified with perfluorocarbon groups and quaternary cationic side chains was synthesized by ring-opening polymerization of cyclosiloxane and graft reaction. The polysiloxane polymers containing pendant groups were the polysiloxanes modified with amino group, perfluorocarbon side chain, tertiary and perfluorocarbon side chains, or quaternary cationic and perfluorocarbon groups. The yields of the modified polymers were 94.2%, 86.7%, 88.4%, 82.5%, respectively. FTIR, 1H NMR, 13C NMR, and 19F NMR were used to characterize the structures of the polysiloxane materials. The dispersion technology of the polysiloxane materials was investigated. The polysiloxane material modified with perfluorocarbon and cationic groups imparted high surface activity. The polyesters treated with the polymers had good repellency to water.  相似文献   
9.
Five perfluorocompounds [perfluoropentane, 4-(perfluoroethoxy)-perfluorobutane, 5-(perfluoroethyl)-perfluorotetrahydrofuran, 2-(trifluoromethyl)-perfluorotetrahydropyran, and 4-(trifluoromethyl)-perfluorotetrahydropyran] were analyzed by electron ionization (EI) and chemical ionization (CI), using methane and isobutane as reagent gases. Under CI conditions, isobutane does not lead to significative results whereas methane leads to high ionic yields [with respect to both CI (isobutane) and EI]. Under EI conditions, practically only fragment ions are observed, with the complete loss of molecular weight. In contrast under CI(CH(4) ) conditions, [M-F](+) ions are produced. Under these conditions, the behavior of oxygen-containing molecules is strongly different from that of perfluoropentane. This is because oxygen can greatly stabilize the formation of the [M-F](+) carbocation by a π-electron donor effect, especially in the case of cyclic structures. Moreover, π-stabilization can be considered a useful tool to rationalize the position of tertiary carbon atom in trifluoromethyl-perfluoro-pyrane isomeric ions. The experimental data formed the starting point for the theoretical calculation, which allowed us to explore the mechanisms of the reactions of CH(5) (+) ions with selected perfluorocompounds. The computational methods used show that a direct protonation of the perfluoroethers (PFEs) by CH(5) (+) as well as iBu(+) is very unlikely. In the theoretical calculations, the PFE molecule served rather as the F(-) donor, and the elimination of HF molecule occurred when the PFE molecule was placed close to H(+) or CH(5) (+) ions. The fact that the latter is very unstable and decomposes to a proton and methane molecule explains why the use of methane in CI is so successful in the generation of [M-F](+) ion. In contrast, the isobutonium cation rearranges to an isopropyl cation/methane complex rather than that it abstracts F(-) from the PFE molecule. Similar results can be expected for other PFEs and perfluoroalkanes (PFAs) because both CH(5) (+) and H(+) were able to abstract the HF molecule also by attacking along the perfluoroalkyl chain of the PFE.  相似文献   
10.
刘俊  胡金波 《化学教育》2019,40(21):1-3
由于氟原子具有较小的原子半径和最强的电负性,氟原子的引入常常会给化合物带来独特的物理、化学和生物性质。含氟化合物已广泛应用于材料、医药和农药等各个领域。介绍了氟原子的基本性质、天然氟化物的存在形式、氟的工业应用、氟在医学方面的应用等。  相似文献   
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