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61.
内皮素、一氧化氮在毛细支气管炎和哮喘患儿中的变化 总被引:1,自引:0,他引:1
周江瑾 《中国小儿急救医学》2003,10(2):90-92
目的 探讨血内皮素 (ET)和一氧化氮 (NO)在毛细支气管炎 (毛支 )和婴幼儿哮喘 (哮喘 )中的变化及意义。 方法 用放射免疫分析法和分光光度比色法分别检测毛支、哮喘患儿急性期和缓解期血ET和NO ,并与正常儿童进行比较。 结果 血浆ET在毛支组和哮喘组 ,急性期均明显高于正常组 (P均 <0 0 1) ,缓解期均下降 ,与正常组比较无显著差别 (P均 >0 0 5 ) ;两组急性期比较无差别 (P >0 0 5 )。与血浆ET一样 ,血清NO在毛支组和哮喘组 ,急性期均显著高于正常组 (P <0 0 1和P <0 0 5 ) ;缓解期则下降 ,与对照组比无显著差别 ,(P均 >0 0 5 ) ;两组急性期相比 ,差异无显著性 (P >0 0 5 )。两组急性期血浆ET与血清NO呈明显正相关 (P <0 0 5 )。 结论 在毛支和哮喘中 ,血ET和NO均升高 ,二者关系密切 ,均可能参与毛支及哮喘的发病 相似文献
62.
PCR快速鉴定actinobacteria三种模板制备方法的比较 总被引:4,自引:0,他引:4
目的 本研究旨在建立准确、简便、快速的放线细菌鉴定技术,为普通和极端环境放线细菌资源的调查和开发利用创造条件。方法 从放线细菌固体培养基上挑取少量菌体,用微波炉法快速制备基因组DNA作为PCR模板,与液体培养法得到的菌体以超声波法或冻融法制备的模板进行了PCR扩增效果的比较研究。结果P CR检测结果表明微波炉法制备的模板可进行有效的体外扩增,目的条带特异,而超声波法或冻融法并不对所有菌株有效,并有非特异扩增产物产生。结论 组合微波炉法快速制备放线细菌基因组DNA技术和23S rRNA特异插入序列PCR扩增技术建立了准确、简便、快速的actinobacteria鉴别体系。 相似文献
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Kinetic analysis shows that iron deficiency decreases liver vitamin A mobilization in rats 总被引:2,自引:0,他引:2
In view of evidence that nutritional status of iron and vitamin A may affect the other nutrient's metabolism, we used model-based compartmental analysis to examine effects of iron deficiency on whole-body vitamin A dynamics in rats. Weanling male Sprague-Dawley rats were fed the AIN93G diet with 2.5 nmol retinyl palmitate/g and either 45 [control (CN)] or 4 microg/g Fe [iron-deficient (ID)] for 8 wk. ID rats consumed food ad libitum; CN rats were food-restricted so that their body weights were the same as ID rats. Two rats/group were killed; liver vitamin A was determined and used for vitamin A balance calculations. [(3)H]Retinol-labeled plasma was administered intravenously to remaining rats, and 27 serial blood samples were collected for 7 wk. At killing, plasma vitamin A was 0.52+/-0.12 (ID, n = 5) vs. 1.34+/-0.12 micromol/L (CN, n = 6; P<0.001), and liver vitamin A was 809+/-94 (ID) vs. 112+/-24 nmol (CN, P<0.001). Plasma tracer data were fit to a three- or four-compartment model using the Simulation, Analysis and Modeling computer program and kinetic parameters were calculated. Vitamin A transfer rate between the retinyl ester storage pool [14+/-3 (ID) vs. 24+/-4 nmol/d (CN), P<0.05] and plasma was lower in ID rats. Vitamin A remained longer in the body [44+/-11 (ID) vs. 22+/-3 d (CN), P<0.05]. Adjusted mean disposal rate was lower in ID (10.0) than CN rats (19.9 nmol/d), as was estimated vitamin A absorption efficiency [58% (ID) vs. 76% (CN)]. Our results suggest that iron deficiency inhibits mobilization of vitamin A stores and may decrease the absorption and irreversible utilization of vitamin A. 相似文献
67.
Byung Mu Lee Ja-June Jang Joung-Soon Kim Young Chan You Sun Ah Chun Hyung Sik Kim Hyung Mee Han Mi Young Ahn Soo Hyun Byun 《Cancer science》1998,89(6):597-603
Gastric adenocarcinoma is the most prevalent cancer in South Korea, and Helicobacter pylori (H. pylori) infection is also common. This study was performed to examine the association between H. pylori infection and gastric cancer, taking into account various other factors. To investigate the association between gastric adenocarcinoma and H. pylori infection, determined by urease-positive reaction in the CLO test, a total of 175 paired specimens (175 tumor and 175 tissues adjacent to tumor) of stomach cancer patients and a total of 113 control specimens were obtained. The positive H. pylori infection rates were 78.9% (138/175) among the patients in specimens of tumor or tissues adjacent to the tumor and 41.6% (47/113) among controls in the CLO test. A positive correlation between H. pylori infection and gastric cancer was observed (age-adjusted odds ratio, 7.0; MH χ2 =34.5 with P <0.0005). These data suggest that stomach cancer patients in Korea have high infection rates of H. pylori regardless of site specificity, and this infection might be causally associated with stomach cancer. 相似文献
68.
The effects of N-ethylmaleimide (NEM), an alkylating reagent to protein sulfhydryl groups, on tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) sodium channels in rat dorsal root ganglion (DRG) neurons were studied using the whole cell configuration of patch-clamp technique. When currents were evoked by step depolarizations to 0 mV from a holding potential of -80 mV NEM decreased the amplitude of TTX-S sodium current, but exerted little or no effect on that of TTX-R sodium current. The inhibitory effect of NEM on TTX-S sodium channel was mainly due to the shift of the steady-state inactivation curve in the hyperpolarizing direction. NEM did not affect the voltage-dependence of the activation of TTX-S sodium channel. The steady-state inactivation curve for TTX-R sodium channel was shifted by NEM in the hyperpolarizing direction as that for TTX-S sodium channel. NEM caused a change in the voltage-dependence of the activation of TTX-R sodium channel unlike TTX-S sodium channel. After NEM treatment, the amplitudes of TTX-R sodium currents at test voltages below -10 mV were increased, but those at more positive voltages were not affected. This was explained by the shift in the conductance-voltage curve for TTX-R sodium channels in the hyperpolarizing direction after NEM treatment. 相似文献
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70.
Vascular endothelial growth factor gene polymorphisms and risk of primary lung cancer. 总被引:17,自引:0,他引:17
Su Jeong Lee Sin Yeob Lee Hyo-Sung Jeon Sun Ha Park Jin Sung Jang Ga Young Lee Ji Woong Son Chang Ho Kim Won Kee Lee Sin Kam Rang Woon Park Tae-In Park Young Mo Kang In-San Kim Tae Hoon Jung Jae Yong Park 《Cancer epidemiology, biomarkers & prevention》2005,14(3):571-575
Angiogenesis is an essential process in the development, growth, and metastasis of malignant tumors including lung cancer. DNA sequence variations in the vascular endothelial growth factor (VEGF) gene may lead to altered VEGF production and/or activity, thereby causing interindividual differences in the susceptibility to lung cancer via their actions on the pathways of tumor angiogenesis. To test this hypothesis, we investigated the potential association between three VEGF polymorphisms (-460T > C, +405C > G, and 936C > T)/haplotypes and the risk of lung cancer in a Korean population. VEGF genotypes were determined in 432 lung cancer patients and 432 healthy controls that were frequency matched for age and sex. VEGF haplotypes were predicted using Bayesian algorithm in the phase program. Compared with the combined +405 CC and CG genotype, the +405 GG genotype found associated with a significantly decreased risk of small cell carcinoma [SCC; adjusted odds ratio (OR), 0.36; 95% confidence interval (95% CI), 0.17-0.78]. The 936 CT genotype and the combined 936 CT and TT genotype were also associated with a significantly decreased risk of SCC compared with the 936 CC genotype (adjusted OR, 0.47; 95% CI, 0.26-0.85 and adjusted OR, 0.44; 95% CI, 0.24-0.80, respectively). Haplotype CGT was associated with a significantly decreased risk of SCC (adjusted OR, 0.39; 95% CI, 0.18-0.87), whereas haplotype TCC conferred a significantly increased risk of SCC (adjusted OR, 1.63; 95% CI, 1.14-2.33). None of the VEGF polymorphisms studied significantly influenced the susceptibility to lung cancer except SCC. However, haplotypes TCT and TGT were significantly associated with the risk of overall lung cancer, respectively (adjusted OR, 0.38; 95% CI, 0.25-0.60 and adjusted OR, 3.94; 95% CI, 2.00-7.76, respectively). These effects of haplotypes TCT and TGT on lung cancer risk were observed in three major histologic types of lung cancer. These results suggest that the VEGF gene may be contribute to an inherited predisposition to lung cancer. 相似文献