Asymmetric dimethyl-arginine and coronary artery calcification in young adults entering middle age: the CARDIA Study.

BACKGROUND: Normal endothelial function depends on nitric oxide (NO) release by endothelial cells. Asymmetric dimethylarginine (ADMA), by competing with L-arginine, inhibits NO production and may lead to endothelial dysfunction and atherosclerotic development. Our aim was to ascertain the association between ADMA and coronary artery calcification (CAC), a marker of atherosclerotic coronary disease burden. DESIGN: A nested case-control study within the Coronary Artery Risk Development in Young Adults (CARDIA) cohort, an observational study among young adults residing in four US cities. METHODS: Participants were 263 white and black male and female cases with the presence of CAC and 263 sex and race-matched controls without evidence of CAC by computed tomography, 33-47 years old in 2000-2001. RESULTS: The median level (range) of ADMA was significantly higher in cases (0.55; 0.20-2.22 micromol/l) than in controls (0.53; 0.32-1.30 micromol/l; P=0.03). In conditional logistic regression adjusting for age, field center, educational attainment, smoking status, alcohol consumption, body mass index, waist circumference, hypertension, diabetes, low-density lipoprotein and high-density lipoprotein-cholesterol, triglycerides, renal function and C-reactive protein, the highest tertile of ADMA, compared with the lowest tertile, was associated with 1.80 (95% confidence interval 1.03-3.15) increased odds of the presence of any CAC. By linear regression, a significant independent relationship was also found between ADMA and the degree of CAC. CONCLUSION: These results support a role for ADMA as a biochemical marker of CAC.     

The role of thyroid scanning in hyperthyroidism

Radionuclide thyroid imaging was performed in 872 consecutive patients with hyperthyroidism. Of these, 84% were found to have diffuse toxic hyperplasia (Graves' disease), while 12% had autonomously functioning nodules (Plummer's disease), 3% had Graves' disease developing in a multinodular gland, and in the remaining 1%, either a clear diagnosis could not be established or the hyperthyroidism was due to thyroiditis or the Jod-Basedow phenomenon. It was found that a thyroid scan seldom provides additional diagnostic information in patients with Graves' disease when a diffuse goitre is present. However, if patients are to be treated with radioiodine (131I), thyroid imaging with tracer quantitation can replace a 24-h 131I uptake measurement, this having the advantages that the patients are required to attend only once, and that the gland size can be measured. In addition, visual confirmation of tracer uptake by the thyroid is obtained and patients with thyroiditis will not receive inappropriate therapy. When single or multiple thyroid nodules are palpated, a thyroid scan is crucial in establishing an accurate diagnosis, as it is not otherwise possible to differentiate between Plummer's disease and Graves' disease developing in a multinodular gland. Indeed, in 20 of our 63 patients (32%) with single autonomously functioning nodules, the initial clinical assessment had been incorrect.     

麦冬类中药组织切片计算机三维重建图鉴

利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。     

用混合粘合剂碳糊电极测定丁螺环酮

用混合粘合剂碳糊电极测定丁螺环酮张正奇，曾鸽鸣，刘传桂，黎艳飞（湖南大学化学化工系，长沙４１００８２）碳糊电极无毒，制作方便，表面更新容易，应用电位范围广，在药物分析中已有应用［１～５］。我们在液体石腊中加入添加剂，组成混合粘合剂，可显著改善电极的检...