Home  About us  Contact
 

Activity Used (activity + used)

Distribution by Scientific Domains
Medical Sciences75%

Selected Abstracts

Competition on the London Stock Exchange

EUROPEAN FINANCIAL MANAGEMENT, Issue 4 2002
Nicholas Taylor
This paper investigates the determinants of the level of competition on the order,driven market organised by the London Stock Exchange. In contrast to previous empirical market microstructure studies, we treat the level of competition as an endogenous variable. The statistical nature of the measures of competitive activity used in this paper necessitate use of a count regression model. Using a sample 50 stocks, we find that users of the system tend to follow the lead of other users (termed the ,herding effect') and that competition is greater during the period when the US exchanges are open (termed the ,US effect'). In addition, the level of competition is positively related to the bid,ask spread pertaining to a particular stock (termed the ,spread effect'). The latter result is most likely due to traders following a strategy where trade immediacy is traded off against price advantage. Finally, we find that the magnitude of the herding effect, the spread effect, and the fit of the count regression models (termed the ,fit effect') vary in a predictable manner across the liquidity of stocks. [source]

Plasma antioxidative activity during atorvastatin and fluvastatin therapy used in coronary heart disease primary prevention

FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2004
Jan Kowalski
Abstract We estimated the effect of atorvastatin and fluvastatin on plasma antioxidative activity used in coronary heart disease (CHD) primary prevention. Anti-oxidative activity of blood plasma was determined by Bartosz et al. method [Curr. Top. Biophys. (1998)22:11,13], based on reduction of preformed cation radical of 2,2,azinobis(3-ethylbenzothiazoline-6-sulphonic acid) by blood plasma. The study comprised 35 patients with CHD risk who were randomly divided into two groups. The atorvastatin group comprised 17 patients who were administered the drug orally in a daily dose of 10 mg and the fluvastatin group consisted of 18 patients on an oral dose of 40 mg once daily. The control group comprised 12 healthy subjects with no drug administration. Blood samples were collected from cubital vein before and after 6-week therapy. Significantly (P < 0.05) increased , in comparison with the initial values , antioxidative activity of blood plasma was found in atorvastatin and fluvastatin groups after 6-week therapy. Moreover, the increase in antioxidative plasma activity in atorvastatin group was significantly higher in comparison with the fluvastatin group. The results of our study have demonstrated that atorvastatin and fluvastatin have an additional mechanism independent of the effect on cholesterol concentration. Thus, we presume that administration of these statins in CHD risk patients may have a beneficial effect. [source]

Associations between the American College of Rheumatology pediatric response measures and the continuous measures of disease activity used in adult rheumatoid arthritis: A secondary analysis of clinical trial data from children with Polyarticular-Course Juvenile Idiopathic Arthritis

ARTHRITIS & RHEUMATISM, Issue 12 2009
Sarah Ringold
Objective To measure associations between the American College of Rheumatology (ACR) pediatric criteria for improvement and the continuous measures of disease activity used for rheumatoid arthritis in adult patients with polyarticular-course juvenile idiopathic arthritis (JIA). Methods In this retrospective analysis of 2 etanercept trials, disease activity was calculated at baseline, 3 months, and 6 months using the Disease Activity Score (DAS), the DAS based on 28 joints (DAS28), the Simplified Disease Activity Index (SDAI), and the Clinical Disease Activity Index (CDAI). The ACR pediatric response and the European League Against Rheumatism (EULAR) response were also determined for the 3-month and 6-month evaluations. Data were analyzed in 94 patients with JIA independent of the treatment arm. Correlation coefficients between measures were calculated for each visit. The areas under the receiver operating characteristic curve (AUC of ROC) were calculated to assess the discriminative properties of the scores for the ACR pediatric response measures. Results The mean DAS, DAS28, CDAI score, and SDAI score were 3.7, 4.7, 30.8, and 36.4, respectively, at baseline, corresponding to high levels of disease activity (CDAI/SDAI) or moderate levels of disease activity (DAS/DAS28). At 3 months, the mean scores corresponded to low (DAS/DAS28) or moderate (CDAI/SDAI) disease activity. At 6 months, the mean scores corresponded to low disease activity (DAS/DAS28/CDAI) or moderate disease activity (SDAI). Most children met the criteria for a good or moderate EULAR response at 3 months and 6 months. The correlation between continuous outcome measures and each pediatric core set component was moderate to very good. The AUC of ROC values for each measure were high (range 0.76,0.98). Conclusion Good correlation and discriminative abilities were seen between the DAS, DAS28, CDAI, and SDAI for the ACR pediatric criteria for improvement. These disease activity measures may be useful for research and clinical care in polyarticular-course JIA. [source]