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81.
Objective To investigate effects of angiotcnsin ( 1-7 ) [ Ang( 1-7 ) ] and enalaprilat on function of isolated rat heart perfused by burn serum. Methods Eighty SD rats were used to prepare burn serum. Hearts of another 24 SD rats were isolated to reproduce Langendorff perfusion model. The rat hearts were divided into different groups with different perfusion fluids as K-H buffer group, K-H buffer containing 20% burn serum group ( burn serum group) , K-H buffer containing 20% burn serum and 2 μg/mL enala-prilat group (enalaprilat group), and K-H buffer containing 20% burn serum and 1 nmol/mL Ang(1-7) group [ Ang(1-7) group]. The rat hearts were perfused for 30 mins with each of above-mentioned fluids in different groups. Then left ventrieular systolic pressure (LVSP) , left ventricular end diastolic pressure ( LV-EDP) , ± dp/dt max, coronary flow(CF) , level of creatine kinase (CK) and lactate dehydrogenase (LDH) in respective coronary effluent were determined. Results Compared with LVSP ( 11.2 ± 1.0 kPa, 1 kPa = 7.5 mm Hg), +dp/dt max (642±53 kPa/s), -dp/dt max (380±61 kPa/s) and CF level in K-H buffer group, CF, LVSP(5.9±0.8, 8.0±1.1, 8.9±1.3 kPa, respectively), +dp/dt max(275±37, 454±48, 479±63 kPa/s, respectively), - dp/dt max ( 135±35, 219±47, 277±58 kPa/s, respectively ) of burn serum group, those levels in Ang(1-7) group, and enalaprilat group were decreased obviously(P<0.05 or P <0.01 ), but LVEDP, level of CK and LDH in coronary effluent were increased. Compared with those parameters in burn serum group, CF, LVSP, ±dp/dt max of Ang(1-7) group and enalaprilat group were increased obviously(P<0.05 or P<0.01), and LVEDP, level of CK and LDH in coronary effluent were decreased obviously(P<0.01). Conclusions Ang(1-7) and enalaprilat can effectively improve left ventricular function of isolated rat heart perfused by burn serum and mitigate myocardial injury.  相似文献   
82.
目的 比较无张力腹股沟疝修补术与传统腹股沟疝修补术在老年患者中应用的临床结果、术后生活质量和经济开支。方法 自2000~2001年60岁以上的老年患者42例行腹股沟疝无张力修补术与42例行传统腹股沟疝修补术者,分类比较。结果 无张力腹股沟疝修补术对于老年患者在复发率、术后镇痛、手术时间和术后下地时间方面均明显优于传统腹股沟疝修补术。结论 无张力腹股沟疝修补术运用在老年患者中,近远期效果均优于传统修补手术。  相似文献   
83.
改进的内眦赘皮矫治术联合重睑成形术Ⅰ期成形   总被引:7,自引:2,他引:5  
目的 探讨改进的内眦赘皮矫治术联合切开法重睑成形术的方法及临床效果。方法 根据内眦赘皮的轻重程度及方向,采用改良的“Z”成形术,切除或切断内眦部形成赘皮的异位眼轮匝肌及皮下筋膜组织,联合切开法重睑成形术行Ⅰ期成形。结果 本组68例患者,术后赘皮消失,泪阜显露适中,内眦间距缩短,重睑外形美观自然。其中,36例随访3个月至3年,术后皮肤切口无可见瘢痕,形态稳定,内眦赘皮无复发,效果满意。结论 该手术方法能够充分矫正内眦赘皮的异常结构,而与重睑成形术同期施术效果稳定,具有一定的临床应用价值。  相似文献   
84.
目的观察鸡精用于产后乳汁分泌的临床效果。方法产后每日早晚各服白兰氏鸡精70ml,共服3d,并与对照组、中药材催乳组对比。结果鸡精有促进早泌乳与增加泌乳量的作用。结论鸡精用于产妇有滋养身体,恢复产妇体力,促进早泌乳和增加泌乳量的作用,且饮用方便,效果好,无不良反应。  相似文献   
85.
目的探讨改良式牙科吸唾管在人工气道护理中的应用效果。方法将2007年6月~2009年1月入住ICU建立人工气道的118例患者分为两组,两组患者进行比较。结果两组患者肺部感染、口腔感染、颜面部皮肤破损发生率及护理工作量实验组少于对照组,差异显著有统计学意义(p<0.01)。结论应用改良式牙科吸唾管持续吸引人工气道患者口腔分泌物,可降低肺部感染、口腔感染、颜面部皮肤破损的发生率,增加患者舒适度,减少护理工作量。  相似文献   
86.
顶空—气相色谱法测定盐酸洛美利嗪中乙腈残留量   总被引:6,自引:1,他引:5  
目的:建立盐酸洛美利嗪原料药中乙腈残留量的测定方法。方法:采用顶空进样法,80%DMF水溶液为溶剂,平衡温度70℃,平衡时间40min,气相色谱条件:采用不锈钢填充色谱柱:柱长2m,内径3mm,粒径为0.25-0.32mm的二乙烯苯与乙基乙烯苯共聚物有机担体为填料,柱温130℃,FID检测器,检测器温度250℃,氮气为载气,流速50mL.min^-1。结果:乙腈在23.46-234.6μg.mL^-1的浓度范围内呈良好的线性关系(r=0.9978),回收率为96.7%(RSD=3.8%),检出限小于40μg.g^-1。结论:本方法简单,快捷且灵敏度高,可以用于盐酸洛洛美利嗪中乙腈残留量的控制。  相似文献   
87.
以浅麻醉和麻痹大鼠为对象,利用计算机平均技术记录强电流刺激腓肠神经诱发的脊髓背表面电位(CDP),观察对侧网状三细胞核(NGC)微量注射L一谷氨酸钠,使神经细胞兴奋后对CDP的影响.实验发现,对侧NGC神经细胞兴奋后,Aβ和Aσ纤维引起的P_1波及Aσ和C类纤维引起的N_3波减小,C类纤维引起的P_2波明显减小,N_4 波消失.以上结果提示:对侧NGC对细纤维诱发的CDP成分有抑制作用.  相似文献   
88.
风湿性心脏病二尖瓣置换术中细胞因子水平的变化   总被引:1,自引:0,他引:1  
目的测定风湿性心脏病二尖瓣置换术中细胞因子水平,了解它们的变化规律。方法 11例体外循环(CPB)下二尖瓣置换术患者,分别于术前,主动脉阻断前,主动脉阻断后5min,主动脉开放后10min、1h、2h、4h、24h测定白介素6(IL-6)、白介素8(IL-8)、白介素10(IL-10)以及肿瘤坏死因子(TNF)。结果IL-6、IL-8、IL-10水平在CPB开始后逐渐升高,在主动脉开放后2h左右达到高峰(P<0.01)。之后逐渐下降,到主动脉开放后24h已显著下降。TNF水平在CPB开始后逐渐升高,在主动脉开放后24h仍维持在很高的水平(P<0.01)。结论CPB下二尖瓣置换术中既有促炎因子水平的升高,又有抗炎因子的激活。  相似文献   
89.
L-2-Hydroxyglutaric acid (LGA) is the biochemical hallmark of patients affected by the neurometabolic disorder known as L-2-hydroxyglutaric aciduria (LHGA). Although this disorder is predominantly characterized by severe neurological findings and pronounced cerebellum atrophy, the neurotoxic mechanisms of brain injury are virtually unknown. In the present study, we investigated the effect of LGA, at 0.25-5mM concentrations, on total creatine kinase (tCK) activity from cerebellum, cerebral cortex, cardiac muscle and skeletal muscle homogenates of 30-day-old Wistar rats. CK activity was measured also in the cytosolic (Cy-CK) and mitochondrial (Mi-CK) fractions from cerebellum. We verified that tCK activity was significantly inhibited by LGA in the cerebellum, but not in cerebral cortex, cardiac muscle and skeletal muscle. Furthermore, CK activity from the mitochondrial fraction was inhibited by LGA, whereas that from the cytosolic fraction of cerebellum was not affected by the acid. Kinetic studies revealed that the inhibitory effect of LGA on Mi-CK was non-competitive in relation to phosphocreatine. Finally, we verified that the inhibitory effect of LGA on tCK was fully prevented by pre-incubation of the homogenates with reduced glutathione (GSH), suggesting that this inhibition is possibly mediated by oxidation of essential thiol groups of the enzyme. Considering the importance of creatine kinase activity for energy homeostasis, our results suggest that the selective inhibition of this enzyme activity by increased levels of LGA could be possibly related to the cerebellar degeneration characteristically found in patients affected by L-2-hydroxyglutaric aciduria.  相似文献   
90.
Despite low end dialysis serum phosphate levels (Pe) the control of phosphate retention remains often unsatisfactory in dialyzed patients. In order to assess the value of Pe in dialyzed children as an indicator of dialytic phosphate removal, we studied serum phosphate kinetics over the period of dialysis and post dialysis and compared these with urea kinetics. A multicenter study was conducted in the 21 French pediatric hemodialysis units and included 144 children under 15 years of age. Blood urea and phosphate concentrations were measured at the beginning, at 45 min later, at the end of dialysis, and 30 min post dialysis. At 60 min and at 360 min post dialysis measurements were made only for a subgroup of 12 children. From the serum levels, reduction ratios for urea (URR) and phosphate (PRR) and post dialysis rebound for urea (PDUR) and phosphate (PDPR) were calculated. URR (over the dialysis session, 72%±9%) was higher than PRR (47%±12%). Moreover, urea removal continued throughout the dialysis period, while most of the reduction in phosphate occurred in the initial dialysis period. Post dialysis urea rebound was limited to the 60th min post dialysis, whereas post dialysis phosphate rebound occurred until the 360th min post dialysis; by this time the serum phosphate levels had almost reached the predialysis levels. In summary, serum phosphate kinetics over dialysis and post dialysis periods in children appear to be misleading for the quantification of phosphate removal, i. e., phosphate clearance is a poor indicator of dialytic phosphate removal. Received September 21, 1995; received in revised form and accepted June 11, 1996  相似文献   
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