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81.
等长运动对正常人、冠心病患者左室心功能的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
目的 :通过核素心血池显像测定静息状态和等长运动后正常人、冠心病患者左室心功能指标的变化 ,探讨等长运动对冠心病诊断的临床价值。方法 :45例正常人、10 0例冠心病患者常规核素平衡法门电路心血池显像测定左室心功能。在静息状态下采集后 ,保持探头和患者体位不变 ,双手握力 5~ 10 min并同时进行采集从而获得静息和握力运动状态下两组血流动力学指标和时间—放射性曲线。11例正常人和 10 0例冠心病患者行冠状动脉及左心室造影 ,两项检查间隔不超过两周。运用 SPSS9.0统计软件进行 t检验和直线相关分析。结果 :左室射血分数(L VEF)、高峰充盈率 (PFR)、左室舒张末期容积 (L VEDV )、左室收缩末期容积 (L VESV )和心率 (HR)在静息(Rest)状态下 ,对照组和冠心病组分别为 (5 2± 9) % vs(4 5± 9% ) ,P<0 .0 1;2 .7± 0 .8EDV/s vs2 .0± 0 .8EDV/s,P<0 .0 1;1.33± 0 .12 vs 1.2 8± 0 .11,P <0 .0 5 ;0 .6 3± 0 .10 vs 0 .0 7± 0 .0 8,P<0 .0 1;7.0± 10 m in- 1 vs 6 9± 9min- 1 ,P>0 .0 5。在等长握力运动 (Stress)状态下 ,对照组和冠心病组分别为 (5 6± 10 ) % vs(4 2± 10 ) % ,P<0 .0 1;3.1± 0 .8EDV/s vs 1.8± 0 .7EDV/s.P<0 .0 1;1.35± 0 .14vs 1.2 5± 0 .12 ,P<0 .0 1;0 .6 0± 0 .1  相似文献   
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本文旨在为IV期非小细胞肺癌患者的治疗提供更新版推荐。本文资料检索源自2002年以来公布的相关随机试验文献。此指南范围限于化疗与生物治疗。更新委员会对这些文献进行了总结并提供了推荐更新。162篇文献符合标准被纳入参考。本推荐基于可改善总生存期的治疗方法。仅改善无进展生存期的治疗方法推动了对毒性及生存质量的监测。对于体力状态评分为0分或1分患者的一线治疗,可推荐以铂类为基础的细胞毒性药物的两药联用。对铂类治疗有禁忌的患者,可采用非铂类细胞毒性两药联合。对于体力状态评分为2分的患者,单一细胞毒性药物即可。对于疾病进展或经过4个周期的治疗仍对治疗无反应的患者,应停止一线细胞毒性化疗。即使在6个周期后患者对治疗仍有反应,亦应停止两药细胞毒性化疗。对于伴有明确的表皮生长因子受体(epidermal growth factor receptor,EGFR)突变的患者,可推荐一线采用吉非替尼治疗;对于EGFR突变为阴性或不明确的患者,细胞毒性化疗更佳。除具有特定临床特征的患者外,可推荐贝伐单抗与卡铂-紫杉醇联用。对于通过免疫组化证实EGFR阳性的肿瘤患者,可推荐西妥昔单抗与顺铂-长春瑞滨联用。多西紫杉醇、厄洛替尼、吉非替尼...  相似文献   
84.
bFGF、EGF和NGF对人角膜内皮细胞生长调控的实验研究   总被引:1,自引:0,他引:1  
目的:探讨碱性成纤维细胞生长因子(Basicfibroblastgrowthfacfor,bFGF)、表皮细胞生长因子(Epidermalgrowthfactor,EGF)和神经细胞生长因子(Nervegrowthfactor,NGF)对体外培养的人角膜内皮细胞的生长调控作用。方法:将相同数量的人角膜内皮细胞接种于96孔板。加入浓度分别为0ng/ml、1ng/ml、3ng/ml、10ng/ml、30ng/ml、100ng/ml的EGF、bFGF和NGF进行培养。5天后MTT法用检测增殖情况。结果:在0ng/ml、1ng/ml、3ng/ml、10ng/ml、30ng/ml、100ng/ml浓度下bFGF组的平均OD值分别为:0.224±0.045、0.239±0.040、0.262±0.0342、0.278±0.0319、0.281±0.0324、0.260±0.0310。EGF组的平均OD值分别为:0.228±0.0304、0.245±0.0418、0.267±0.0454、0.275±0.0347、0.271±0.0449、0.250±0.0253。NGF组的平均OD值分别为:0.216±0.0187、0.228±0.0226、0.231±O.0225、0.242±0.0279、0.245±0.0294、0.247±0.0349。结论:bFGF在30ng/ml范围内对内皮细胞生长有促进作用,并具有剂量依赖性。高于100ng/ml时促生长作用降低。EGF在10ng/ml范围内对内皮细胞生长有促进作用,并具有剂量依赖性。高于30ng/ml时促生长作用降低。NGF本次实验剂量范用内对角膜内皮细胞生长无明显作用。  相似文献   
85.
No comprehensive data on sources or risk factors of cadmium exposure in Ukrainian children are available. In this we measured the blood levels of cadmium among 80 Ukrainian children and evaluated sources of exposure. A nested case-control study from a prospective cohort of Ukrainian 3-year-old children was conducted. We evaluated predictors of elevated blood cadmium using a multivariable logistic regression model. The model included socioeconomic data, parent occupation, environmental tobacco smoke, hygiene, body-mass index, and diet. Dietary habits were evaluated using the 1992 Block-NCI-HHHQ Dietary Food Frequency survey. Elevated cadmium was defined as blood levels in the upper quartile (0.25 microg/L). The mean age for all 80 children was 36.6 months. Geometric mean cadmium level was 0.21 microg/L (range = 0.11-0.42 microg/L; SD = 0.05). Blood cadmium levels were higher among children taking zinc supplements (0.25 vs 0.21 microg/L; P = 0.032), children who ate sausage more than once per week (0.23 vs 0.20; P = 0.007) and children whose fathers worked in a by-product coking industry (0.25 vs 0.21; P = 0.056). In the multivariable model, predictors of elevated blood cadmium levels included zinc supplementation (adjusted OR = 14.16; P < 0.01), father working in a by-product coking industry (adjusted OR = 8.50; P = 0.03), and low body mass index (<14.5; adjusted OR = 5.67; P = 0.03). This is the first study to indicate a strong association between elevated blood cadmium levels and zinc supplementation in young children. Whole-blood cadmium levels observed in this group of Ukrainian children appear to be similar to those reported in other Eastern European countries.  相似文献   
86.
正常人脑中每mol tau蛋白含磷量为2~3mol,而AD患者脑中每mol tau蛋白含磷量为5~9mol,比对照组高2~3倍.AD易溶型异常磷酸化的tau蛋白和神经原纤维缠结中的tau蛋白均被外源凝集素GNA标记,并以强度递降的顺序被MAA,PNA和DSA标记,但不被SNA标记,而正常人脑tau蛋白不与上述任一凝集素反应.结果提示,Alzheimer患者脑中tau蛋白除被异常过度磷酸化修饰外,不同程度地还被甘露糖,末端α-(2-3)连接的半乳糖,末端半乳糖-β-(1-3)-N-乙酰半乳糖胺及半乳糖β-(1-4)-N-乙酰半乳糖胺糖基化修饰.  相似文献   
87.
INTRODUCTION Polycyclic aromatic hydrocarbons (PAHs) such as B[a]P are widespread environmental contaminants formed as byproducts of combustion[1]. PAHs have been found to be potent mammary carcinogens in rodents[2-3]. It is believed that B[a]P requires biological activation through oxidative metabolism to be carcinogenic. The ultimate carcinogenic metabolite has been considered to be the cytochrome P450 isozyme- and microsomal epoxide hydrolase- derived metabolite, BPDE, which forms…  相似文献   
88.
To express the core protein of HIV-1 of Chinese prevalent strata (HIV-1[CN]) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sal I was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kDa, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13% of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80%-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85%. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting.  相似文献   
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Glyphosate-based herbicides are widely used in agricultural systems. Although the target organism are particularly plant organisms, there are numerous studies showing adverse effects in aquatic animals, such as inhibition of acetyl cholinesterase, effects on kidney, liver, and gill and stressors effects. This study analyzed the effects of commercial formulation of glyphosate on feeding behavior in Pacu (Piaractus mesopotamicus). Fish were exposed to three glyphosate concentrations (0.2, 0.6, and 1.8 ppm) for 15 days. At concentrations of 0.2 and 0.6 ppm, food intake decreased on day 13 and then returned to normal on day 15. At the highest glyphosate-based herbicide concentration, 1.8 ppm, food consumption decreased dramatically and did not recover on day 15. This study showed that glyphosate-based herbicide at sub-lethal concentrations can affect feed intake in pacu and consequently inhibits its growth.  相似文献   
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