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41.
应用电子自旋共振波谱仪(ESR)直接检测了缺血-再灌注兔心肌肌浆网自由基的变化,以探讨肌质网系统与氧自由基的关系。实验中将20只兔随机分为再灌注对照组、超氧化物歧化酶(SOD)组、ATP-氯化镁组和人参皂甙Re组。实验结果,g值2.0046处为半醌自由基波谱,其相对浓度各组依次为78.94±2.126,14.46±2.86,20.65±7.65,14.66±3.67(x±SD),对照组与用药组均有显著性差异(P<0.05),表明缺血-再灌注兔心肌肌浆网产生大量的自由基,用ESR可以直接检测到半醌自由基,外源性高能磷酸盐制剂ATP-氯化镁及人参皂甙Re与超氧化物歧化酶一样,发挥清除兔心肌肌浆网自由基的作用。 相似文献
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目的 观察营养素食预防化疗患者便秘的效果。方法 选择128例化疗患者,随机分为观察组和对照组各61例,对照组常规正常饮食,观察组于化疗开始当天实施营养素食.连续7~10d,比较两组患者便秘发生率及体重、血红蛋白、白蛋白等指标。结果 对照组便秘发生率显著高于观察组(P〈0.01);两组化疗后营养指标比较,差异无显著性意义(均P〉0.05)。结论 营养素食对化疗患者便秘有较好的预防作用。 相似文献
44.
Matthias Peltz Tian-Teng He Glenn A Adams Robert Y Chao Michael E Jessen Dan M Meyer 《The Journal of heart and lung transplantation》2005,24(7):896-903
BACKGROUND: Lungs harvested for transplantation are stored while inflated with oxygen, which can serve to support oxidative metabolism. However, strategies aimed at increasing graft metabolism during storage have received little attention. In this study, we added pyruvate to the preservation solution Perfadex and measured the effects on oxidative metabolism and reperfusion lung function. METHODS: Rat lungs were stored for 6 and 24 hours in low-potassium dextran solution at 10 degrees C containing either 5 mmol/liter uniformly carbon-13 (U-(13)C) labeled glucose (Perfadex), 32 mmol/liter 3-(13)C pyruvate (pyruvate), or both (combined). Oxidation of exogenous substrates was measured as the incorporation of (13)C into tricarboxylic acid cycle intermediates by magnetic resonance spectroscopy. Additional groups of lungs with each substrate modification were preserved for 6 or 24 hours and then reperfused. RESULTS: Enrichment of tricarboxylic acid cycle intermediates was low in the Perfadex group (9% at 6 hours and 32% at 24 hours of storage, respectively). In contrast, enrichment was significantly increased in both the pyruvate group (50% and 59%, respectively) and combined group (39% and 54%, respectively) compared with the Perfadex group (p<0.01). Graft function was excellent after 6-hour storage in all groups. All lungs stored for 24 hours exhibited inferior lung function, but oxygenation, pulmonary artery pressures, and airway pressures in the combined group were significantly improved compared with the Perfadex group (p<0.05). CONCLUSIONS: Preservation solution substrate composition influences graft metabolism during storage. The addition of pyruvate to Perfadex increases metabolism during storage and improves reperfusion lung function. 相似文献
45.
A prototype electronic radial scan ultrasound endoscope has been developed by Olympus (Tokyo, Japan) for endoscopic ultrasound (EUS) study. The ultrasound view‐angle of this model is 360° vertical to the scope. Though the diameter of the scanner and the shaft of the scope is bigger than those of the present mechanical radial scan model, clinical manipulation of the new scope is the same as that of the present model. Image quality of the ultrasound picture demonstrated by the electronic radial model was as clear as those provided by the mechanical radial scan model. Ultrasound penetration was better and satisfactory because of less echoic reduction compared to the mechanical radial model. The newly developed electronic radial model can be evaluated as an ultrasound endoscope for the next generation. The advantage of this system is to facilitate the clinical use of color Doppler function and tissue harmonic imaging, and this system can be operated by the same monitor unit as a convex model of ultrasound endoscope. 相似文献
46.
Jun-ichi Shikata MD Kazuhiko Ohtaki Kenjiro Amino Yoshitsugu Takeda 《Surgery today》1990,20(6):660-664
Two nationwide questionnaire surveys of intestinal obstruction in Japan were undertaken, covering two two-year periods, from
January, 1975 to December, 1976 and from January, 1985 to December, 1986, respectively. The findings of a comparative review
of these two surveys indicated that although the overall mortality of intestinal obstruction had not changed between 1975/76
and 1985/86, being 6.8 per cent and 6.5 per cent, respectively, simple adhesive obstruction had decreased from 3.2 per cent
in 1975/76 to 2.0 per cent in 1985/86. The main cause of adhesion was laparotomy and in cases of both simple adhesive obstruction
and strangulated adhesive obstruction, the rate of adhesion secondary to laparotomy of the upper gastrointestinal tract and
colon and rectum had increased between 1975/76 and 1985/86. Obstructions caused by neoplasms had increased from 8.2 per cent
in 1975/76 to 10.0 per cent in 1985/86, while those caused by adhesions had incresed further still, from 42.5 per cent in
1975/76 to 60.8 per cent in 1985/86. Among the latter group, nonoperatively treated cases had increased, which may be accounted
for by the fact that facilities which adopt non-operative treatment using intestinal decompression as the first choice for
simple adhesive obstruction cases have increased. In both surveys, the mortality of cases receiving nonoperative treatment
was lower than that of operative cases. 相似文献
47.
本实验复制24只杂种犬心肌缺血再灌注损伤病理模型,应用与生理盐水、丹参对比的方法观察通脉灵对血液动力学及心功能的影响。结果表明,通脉灵小剂量组(TM1G)、通脉灵大剂量组(TM2G)和丹参对照组(DSG)的心输出量(CO),心脏指数(CI),心搏指数(SI)、左室内压峰值(LVSP)及左室内压最大变化速率(±dp/dtmsx)均明显高于生理盐水对照组(NSG)。本实验证明,通脉灵主要是通过保护心肌舒缩功能改善血液动力学指标进而防止缺血再灌注时心功能不全的发生。 相似文献
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