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91.
腺苷预处理对人未成熟心肌缺血再灌注损伤的保护作用   总被引:1,自引:0,他引:1  
目的探讨腺苷预处理对人未成熟心肌缺血再灌注损伤的保护作用及其可能机制。方法将42例5岁以下行室间隔缺损修补术的患儿随机分成腺苷组和对照组,每组21例。腺苷组在术前用腺苷预处理,对照组经相同路径滴入相同体积的生理盐水后开始转流。观察心肌肌钙蛋白-I(cTnI)、肌酸激酶同工酶(CK-MB)、心肌超微结构改变,记录和计算两组自动复跳率、T波倒置发生率、室性心律失常发生率、术后平均住院日(d)。结果腺苷预处理明显减少了cTnI、CK-MB的漏出,在心肌超微结构和心电活动方面具有良好的保护作用。结论腺苷预处理对人未成熟心肌缺血再灌注损伤具有保护作用。  相似文献   
92.
Summary Although recognized by pediatric cardiac surgeons, aortic insufficiency as a technical complication after tetralogy of Fallot repair is poorly documented, especially if it occurs late. The case of a boy with aortic insufficiency 10 years after complete tetralogy repair is described. No documentation in the literature other than summary statements in textbooks of this occurence was found.  相似文献   
93.
Summary Five compounds which were identified as potential new anticancer drugs inin vitro screening with the human tumor colony forming assay were selected for further evaluation usingin vitro andin vivo models of human ovarian cancer. Three of five compounds were found to inhibitin vitro colony formation of ovarian cancer cell lines derived from both untreated and combination chemotherapy refractory patients. One compound was also found to prolong survival in a human ovarian carcinoma xenograft model system. This compound, chloroquinoxaline sulfonamide, was selected for development and has shown preliminary indication of activity in phase I clinical testing.  相似文献   
94.
Of 70 cycles stimulated with clomiphene and human menopausal gonadotropin (hMG) for an in vitro fertilization-embryo transfer (IVF-ET) program, a short luteal phase of 11 days or less was found in 18. In this group the mean estradiol and progesterone levels were elevated in the early luteal phase. Despite the elevated initial values, progesterone levels fell rapidly at the mid luteal phase as a sign of premature luteolysis. The mean total amount of gonadotropin administered and the mean number of follicles punctured and of oocytes recovered did not show any significant difference between the groups of normal and short luteal phases. The present findings support the theory that hyperestrogenism in the early luteal phase may initiate the premature luteolysis observed in clomiphene-menopausal gonadotropin-stimulated cycles.  相似文献   
95.
报告接受彩色多普勒超声心动图检查的老年患者162例,其中75例有不同程度的主要动脉瓣关闭不全(Ar)。老年(Ar)的病因构成与中,老年前期者明显不同,主动脉,瓣钙化及原因不明者的比例占多数(67%)。主动脉瓣钙化者Ar程度多较重。主动脉瓣钙化及原因不明Ar患者的其他三个瓣膜返流检出率及和程度均明显高于无Ar的老年患者。表明多瓣膜退行性病变是此类Ar患者的原因之一。  相似文献   
96.
In a prospective, controlled, randomized study where two differentagonists were used, we compared three different long desensitizationprotocols for induction of multiple follicular growth in medicallyassisted conception cycles. In protocol A, 30 patients wereinjected with buserelin twice a day for 15 days prior to ovarianstimulation until human chorionic gonadotrophin (HCG) administration.In protocol B, 30 patients were injected with a single doseof long acting Triptorelin (3.75mg) 15 days before the ovarianstimulation onset. In protocol C, 30 patients were injectedwith the long acting Triptorelin 4 weeks before ovarian stimulationfollowed by daily administration of 0.1 mg of the same agonistuntil HCG injection. There was no difference in the ovarianresponse to exogenous gonadotrophin stimulation, except forthe presence of premature luteinization in two patients in groupB. A significantly higher number of mature oocytes was collectedfrom patients with protocol A; however, the fertilization andcleavage rate demonstrated no significant difference among thethree groups of patients. The ongoing pregnancy rate and theimplanation rate per treatment cycle were very similar in thethree study groups. When the convenience, cost and side-effectsfor the patient are being considered, protocol B should be selectedas the first choice when the agonist is utilized for the purposeof inducing pituitary desensitization before and during ovarianstimulation.  相似文献   
97.
报告36例慢性肾功能不全患者的血浆心钠素、肾素、血管紧张素Ⅱ、醛固酮水平及其相互关系。结果表明:①慢性肾功能不全患者的血浆心钠素水平明显高于对照组值(P<0.0l);②慢性肾功能不全患者中并发高血压者与血压正常者血浆心钠素水平相近,但均高于对照组(P<0.01);③慢性肾功能不全患者肾素—血管紧张素—醛固酮系统(RAAS)活性增高,但心钠素与醛固酮无明显相关。提示血浆心钠素测定在慢性肾功能不全的诊断中有重要意义。  相似文献   
98.
目的研究房性、室性早搏联律间期缩短与桡动脉图的关系,探讨早搏对血流动力学的影响。方法经心电图诊断为房性早搏48例及室性早搏51例,再应用心功能仪检查,通过信号处理技术对早搏桡动脉图形进行面积积分。结果①早搏桡动脉图积分面积提前率〉40%时最小,20%-40%时居中,〈20%时最大(P〈0.05)。②提前率相同情况下,左房与右房的早搏桡动脉图积分面积比较差异无统计学意义(P〉0.05);左室与右室的早搏桡动脉图积分面积比较差异有统计学意义(P〈0.05)。③早搏时的桡动脉图积分面积最小,早搏前第一个窦性心搏居中,早搏后第一个窦性心搏最大(P〈0.05)。结论早搏对血流动力学的影响主要与早搏的联律间期长短有关,室性早搏还与其发生部位有关,早搏的代偿间歇,不能改善对血流动力学的影响。  相似文献   
99.
Endothelin-1 in children with chronic renal failure   总被引:1,自引:0,他引:1  
Endothelin-1 (ET-1) was meansured after extraction from plasma of normal adults (5.9±1.9 pg/ml,n=22), normal children (7.1±1.86 pg/ml,n=29), nonhaemodialysed children with chronic renal failure (CRF) (11.1±1.8 pg/ml),n=10), renal graft recipients (9.5±3.4 pg/ml,n=37), haemodialysed children 24 h after a haemodialysis session (20.02±10.9 pg/ml,n=26) and haemodialysed children before and after a haemodialysis session (15.31±10.6 and 13.8±8.5 respectively,n=14). A sensitive and specific radioimmunoassay was used. ET-1 was significantly higher in non-haemodialysed CRF children and in renal graft recipients than in normal children (P<0.001 andP<0.01, respectively) and significantly higher in haemodialysed children when compared with normal children, non-haemodialysed CRF children and renal graft recipients (P<0.001). ET-1 concentrations were similar in normal children and normal adults. ET-1 was inversely correlated with glomerular filtration rate in non-haemodialysed CRF children (r=–0.39,P<0.01) and positively correlated with extracellular volume in haemodialysed children (r=0.435,P<0.03). After haemodialysis, ET-1 increased in 6 and decreased in 8 of the 14 children studied before and after a haemodialysis session.  相似文献   
100.
目的 :研究卵巢上皮性癌诱导型一氧化氮合酶 (iNOS)的转录水平。方法 :原位杂交法检测 71例卵巢上皮性癌 ,13例卵巢良性肿瘤及 11例正常卵巢组织中iNOSmRNA表达水平。结果 :卵巢上皮性癌中iNOSmRNA高于正常卵巢组织和卵巢良性肿瘤 ,P<0 .0 5。但卵巢上皮性癌Ⅲ ,Ⅳ期与Ⅰ ,Ⅱ期比较无显著差异 ,P>0 .0 5。分化程度比较 ,中、低分化组明显高于高分化组 ,但中、低分化组织间差异无显著性。结论 :诱导型一氧化氮合酶转录水平的升高 ,是引起诱导型一氧化氮合酶水平升高的主要原因 ,在卵巢上皮性癌发生、发展中发挥一定作用  相似文献   
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