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11.
L-丙酰肉碱对再灌注心肌损伤的保护及体外抗自由基作用 总被引:1,自引:0,他引:1
目的:观察L-丙酰肉碱对缺血再灌注心肌的保护作用,并探讨其机理。方法:采用大鼠在体心脏冠状动脉前降支阻断5min造成缺血再灌注模型,持续心电监护,观察心律失常与心功能指标;应用电子顺磁共振观察L-丙酰肉碱对Fenton体系及二甲基亚砜(DMSO)碱性有氧体系产生自由基的作用。结果:L-丙酰肉碱静脉给药明显减少再灌注时室性心动过速、室性纤维颤动的发生(P<0.05),促进再灌注后左室收缩压、左室压最大上升速率、左室压最大下降速率、心力环面积的恢复,与对照组相比,各参数均明显增高(P<0.05);静脉注射L-丙酰肉碱100mmol/L时促进Fenton体系OH的产生,而500mmol/L时产生明显抑制作用,L-丙酰肉碱明显抑制DMSO碱性有氧体系OS的产生。结论:L-丙酰肉碱明显减少再灌注心律失常的发生,促进再灌注后心功能的恢复。推测它对自由基的作用可能是再灌注损伤保护机理之一。 相似文献
12.
Reactive oxygen species and human spermatozoa: physiology and pathology 总被引:20,自引:1,他引:19
The role of reactive oxygen species (ROS) in the pathophysiology of human sperm function has been emphasized in recent years. ROS production in semen has been associated with loss of sperm motility, decreased capacity for sperm–oocyte fusion and loss of fertility. There is a current presumption that the most prolific source of ROS in sperm suspensions is an NADPH oxidase located in leukocytes or in spermatozoa which produces superoxide which is further converted to peroxide by the action of superoxide dismutase. Hydrogen peroxide has been recognized as the most toxic oxidizing species for human spermatozoa, which are very sensitive to lipid peroxidation owing to the high content of polyunsaturated fatty acids in their plasma membrane, though this is not the sole mechanism by which sperm function might be impaired by ROS. Although the excessive production of ROS is detrimental to human spermatozoa, there is a growing body of evidence which suggests that ROS are also involved in the physiological control of some sperm functions. This review focuses on the nature and source of the ROS generated by human spermataozoa as well as their operational mechanisms and their effects, which may be detrimental or beneficial. 相似文献
13.
Jen auo Hirschberg 《Early child development and care》1990,65(1):57-69
During a period of twenty years [1969-1988] the author has observed 614 cases of congenital malformations and noninflammatory diseases of the larynx in infants and young children, Budapest. He summarizes the most characteristic symptoms of laryngeal pathology in infants, and discusses the diagnostic possibilities. Among the latter, spectrographic analyses complemented by auditory evaluation of pathological cry and different breathing noises play an important role. Based on his investigation author differentiates 20 kinds of pathological crying sounds and 4 basic forms of stridor. He describes the acoustic attributes of different pathological sound phenomena and summarizes characteristic voice changes. 相似文献
14.
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16.
Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献
17.
本文研究结果表明,应用无血清培养体系对鼠中孕期乳腺组织细胞(COMMA-1D细胞)、鼠乳腺肿瘤细胞(FUKU细胞)以及CD8F1细胞的原代培养中。BM Matrigel是一良好的细胞附着和细胞生长的促进剂,而Ⅳ型胶原、昆布胺酸和Vitrogen 100对上述细胞的附着和生长也有一定的作用。BM Matrigel和昆布胺酸对FUKU细胞的克隆产率也有显著的促进作用,而昆布胺酸应用方便,价格较低,更适于在实验研究中推广应用。 相似文献
18.
目的:提高前臂预成皮瓣整复术的护理水平.方法:通过术前心理护理,供区的皮肤保护,口腔装备,术后环境准备和卧位,皮瓣观察,切口护理,饮食和口腔护理进行评价.结果:预成皮瓣正常成活,色泽红润如期修复腭部缺损.结论:良好的护理可以提高前臂预成瓣移植的成功率. 相似文献
19.
R.J.W. de Keizer 《International ophthalmology》1997,21(6):335-341
In a prospective study the results of a pterygium excision in 54 patients (57 eyes) who underwent a superficial free conjunctival
autograft (FCG) were compared to those of patients who were treated with postoperative90Sr-irradiation. In 51 cases the minimum
follow-up was six months, the maximum follow-up seven years. We divided the study up into a randomized part and an open part.
In the randomized part, surgery of a primary pterygium was performed in 25 eyes, of which 16 were treated with a FCG and compared
with 9 eyes with primary pterygium surgery and postoperative90Sr beta-irradiation. In the same period 16eyes were treated
because of a recurrent pterygium: 8 with FCG and 8 with90Sr-irradiation. In the open part of the study16 eyes with primary
pterygium were successively treated with FCG alone.
The results showed in the randomized, as well as in the open study on primary surgery with a minimum follow-up of six month,
one recurrence in each of the FCG-groups (2 out of 31 eyes =6.4%), and no recurrences in the 90Sr-group(0%). In the randomized
group of patients treated for a recurrent pterygium one recurrence developed in the FCG group (1 out of 8 eyes =12.5%) and
one in the 90Sr-group (1 out of 7 =14.6%). Analysis of other clinical parameters showed that postoperative treatment with
corticosteroids, nonsteroidal anti-inflammatory drugs, and artificial tears was necessary for a longer period in the FCG group
than in the90Sr-group.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
20.
烟叶硒蛋白对人红细胞的辐射溶血及自由基的作用 总被引:5,自引:0,他引:5
本文观察了烟叶硒蛋白对人红细胞60Coγ照射溶血的影响,发现硒蛋白对红细胞γ照射溶血有极好的预防效果,同时采用电子自旋共振法(ESR)发现硒蛋白对羟自由基有明显的清除作用,并具有明显的剂量-效应关系,在相同浓度下具有优于亚硒酸钠及不含硒的同类蛋白的作用,提示硒蛋白有更好的生物效应。 相似文献