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21.
肺内源性和肺外源性呼吸衰竭机械通气的临床对比研究 总被引:8,自引:4,他引:4
目的探讨肺内源性和肺外源性呼吸衰竭机械通气时的肺保护性策略。方法通过25例呼吸衰竭中12例肺内源性和13例肺外源性机械通气临床资料的回顾性分析,对比研究两组呼吸力学差异时对通气模式选择、参数设置和调节的影响,以及肺保护的实施方法。结果在两组APACHE-Ⅱ评分、平均年龄和Vt设置无差异的条件(P>005)下,肺内源性组PEEP/CPAP、PSV、f的需设值均明显高于肺外源性组(P<001)。肺内源性组Pplat、PIP、Raw的监测结果大于肺外源性组,而Crs小于肺外源性组(P<001)。肺内源性组417%和肺外源性组154%因MOF而死亡(APACHE-Ⅱ评分均>20分),组间比较有显著差异(P<001)。结论肺内源性和肺外源性呼吸衰竭机械通气时,实施肺保护的方法不同。前者应首选压力预置通气模式,后者可首选容量预置通气模式。以设置中、小Vt为原则,按个体化的通气需求而设置f和加用恰当的PSV、CPAP/PEEP对减少VILI、病死率可能有益。 相似文献
22.
Evren Isci Halil Ibrahim Canter Abdullah Kecik 《European journal of plastic surgery》2007,30(1):45-46
Rabbits are the experimental animals of choice in many studies including flaps, wounds, and topical trials for new pharmacological
agents. Because the topical drugs and other materials used for dressing are irritating to the animal, they tend to remove
dressings, bandages, drapes, insensate flaps, and also topical drugs by scratching, licking, and biting if they are within
the reach of the animal. In this study, we report an easy to prepare, user-friendly, comfortable, and cheap dressing protector
called a dressing shield to prevent these problems. 相似文献
23.
阿片肽及其受体系统在缺血性脑损伤的病理生理发展过程中具有非常重要的作用。其在缺血性脑损伤中的作用尚存争议,本文综述了阿片肽及其受体系统在缺血性脑损伤中的作用及其可能机制,有助于探索阿片肽在围术期的合理应用,为缺血性脑损伤防治研究提供新方向。 相似文献
24.
WEIGUANG ZENG PIERRE-OLIVIER REGAMEY KEITH ROSE YUZHOU WANG ERNST BAYER 《Chemical biology & drug design》1997,49(3):273-279
The use of N, O-bisFmoc-N-(2-hydroxy-4-methoxybenzyl) amino acid derivatives in the synthesis of peptides with difficult sequences has already been described. With these amino acid derivatives the reversible protecting group 2-hydroxy-4-methoxybenzyl (Hmb) for the backbone amide bonds of peptide chains is introduced, and thus the aggregation due to hydrogen-bond interchain association is inhibited. This paper describes the synthesis and use of Fmoc-N-(2-hydroxy-4-methoxybenzyl)amino acid derivatives as an alternative means of introducing Hmb backbone protection. These new monoFmoc derivatives were obtained in higher yield than the bisFmoc derivatives. Coupling yields to the amino peptide resin were the same as those obtained with bisFmoc derivatives, under the TBTU/HOBt/DIEA conditions. We also compared different syntheses of a difficult peptide with the Fmoc approach [triple coupling, capping, use of chaotropic agents, backbone protection using monoFmoc (Hmb)Ala] and with optimized Boc chemistry. Both the backbone protection and optimized Boc chemistry approaches gave the desired product in excellent yield and purity. © Munksgaard 1997. 相似文献
25.
RACHEL PHILOSOF-OPPENHEIMER ISRAEL PECHT MATI FRIDKIN 《Chemical biology & drug design》1995,45(2):116-121
The facile thiolytic cleavage of the O-2,4-dinitrophenyl (Dnp) tyrosine bond was applied to the solid-phase synthesis of the 22-amino acid residue peptide H-Asp-Ala-Val-Tyr -Thr-Gly-Leu-Asn-Thr-Arg-Asn-Gln-Glu-Thr-Tyr -Glu-Thr-Leu-Lys-His-Glu-Lys-OH, corresponding to positions 62-83 in the chain of the type 1 receptor for Fcε, domains expressed on the rat mucosal-type mast cells (line RBL-2H3). A method for the spectrophotometric determination of insoluble O-Dnp as well as of unprotected phenolic moieties of tyrosine was developed. It is based on monitoring S-Dnp-2-mercaptoethanol, produced upon O-Dnp thiolysis by 2-mercaptoethanol. © Munksgaard 1995. Dedicated to the memory of Dr. Susumu Funakoshi, a dear friend and a leader in peptide chemistry. 相似文献
26.
The involvement of children in research studies is historically fraught with difficulties. Experiments on children without their consent or knowledge have been carried out in the past and thus the need for stringent ethical control is undoubtedly necessary. However this paper argues that the need to protect children from unethical research has somehow become entwined in the web of secrecy that surrounds the very nature of child abuse. In the name of 'protection' are children in danger of not having their voice heard?
In the foreword to 'Listening to Children' (Alderson, 1995) Roger Singleton writes, 'much research is carried out on and about children, but seldom with children. Children themselves are often strangely silent'. This paper draws on recent literature on the institutional abuse of young people in residential care and the lack of voice that those abused in residential care have traditionally had, suggesting that their silence is not 'strange' but perhaps contrived.
This paper does not repeat the work of Alderson (1995) and make suggestions as to how research with children may best be carried out, but seeks to address the issues in relation to research with children who are in institutions. 相似文献
In the foreword to 'Listening to Children' (Alderson, 1995) Roger Singleton writes, 'much research is carried out on and about children, but seldom with children. Children themselves are often strangely silent'. This paper draws on recent literature on the institutional abuse of young people in residential care and the lack of voice that those abused in residential care have traditionally had, suggesting that their silence is not 'strange' but perhaps contrived.
This paper does not repeat the work of Alderson (1995) and make suggestions as to how research with children may best be carried out, but seeks to address the issues in relation to research with children who are in institutions. 相似文献
27.
1992~1993年间为180例冠脉病变的病人施行冠脉搭桥术,全部病人均采用核甙抑制剂利多氟嗪预处理和低温(28℃)间断缺血心停搏进行术中心肌保护。平均每例病人作冠状动脉端吻合3~4个,每个吻合口用9分钟,主动脉阻断累加时间约25分钟,体外循环时间90分钟,术后医院死亡率1.6%(3/180),无术后心梗发生。作者认为,冠脉搭桥术的术中心肌保护可采用核甙抑制剂和间断缺血心停搏方法,而不用心肌停搏液。 相似文献
28.
利多氟嗪加强间断缺血心停搏心肌的保护作用 总被引:1,自引:1,他引:0
通过对16条犬常温下用利多氟嗪(lidoflazine)预处理加强间断主动脉阻断心停搏心肌保护作用的实验研究。16条犬随机分为对照组和实验组。结果发现,实验组心脏血流动力学的恢复要明显优于对照组。二组间心肌组织ATP、腺苷和肌苷以及冠脉回流液中CPK、CPK-MB、LDH、SOD和MDA值均有显著性差异(P>0.05)。作者认为,冠脉搭桥术中采用间断缺血心停搏时加用利多氟嗪有利于保存心肌能量,减轻心肌再灌注损伤和术后迅即恢复心脏功能。 相似文献
29.
为了探讨常温体外循环下采用缺血预调行心肌保护的研究,通过建立犬的常温体外循环全心缺血预调模型,旨在探讨心内直视手术缺血预调保护心肌的可能性。预调组采用升主动脉阻断5分钟,放开10分钟,反复三次的方式预调心脏;对照纽简单并行循环45分钟,而后两组均接受30分钟缺血和60分钟再灌注。结果显示,预调组室颤发生率低(16.7 VS 83.3%P=0.04),无再灌注心律失常(0 VS66.7%P=0.03),心肌ATP消耗减慢(4.69 1.050 VS 2.35±0.86μmol/g wet wt P<0.01),乳酸积累减少(4.49±0.86 VS 9.80 5.53mg/g wet wtP<0.05),心肌细胞超微结构损伤轻。结论:常温体外循环下应用缺血预调保护犬的心肌是可行而有效的。 相似文献
30.