The potential felt by a single electron within a molecule represents the total interaction energy of this electron with all nuclei and the rest electrons in the molecule and is an important quantity. It is formulated ...The potential felt by a single electron within a molecule represents the total interaction energy of this electron with all nuclei and the rest electrons in the molecule and is an important quantity. It is formulated and then calculated by using the ab initio MELD program plus a separate calculation program. We have systematically investigated and discussed this kind of potentials for a series of molecules. In terms of the three dimensional graph, the variation of the potential acting on the single electron within a molecule has clearly and visually been shown, and hence the electronic movement and the chemical bonding can be deeply understood.展开更多
Background: Patients with stroke or transient ischemic attack are at high risk of another stroke, and there is need for improved strategies to predict recurrent stroke. Objective: To assess the prognostic value of lev...Background: Patients with stroke or transient ischemic attack are at high risk of another stroke, and there is need for improved strategies to predict recurrent stroke. Objective: To assess the prognostic value of levels of soluble vascular cell adhesion molecule 1 (sVCAM- 1), N-terminal pro-B-type natriuretic peptide (NT-proBNP), C-reactive protein, homocysteine, renin, and lipids and lipoprotein particle concentration and size in patients with previous stroke or transient ischemic attack. Design, Setting, and Participants: A nested case-control study of participants of the Perindopril Protection Against Recurrent Stroke Study was performed. The Perindopril Protection Against Recurrent Stroke Study was a placebo-controlled trial of a perindopril erbumine-based, blood pressure-lowering regimen that reduced ischemic stroke risk by 24% among individuals with previous stroke or transient ischemic attack. Each of 252 patients who experienced ischemic stroke during a mean follow-up of 3.9 years was matched to 1 to 3 control patients. Matching variables were age, sex, treatment allocated, region, and most recent qualifying event at randomization. Main Outcome Measures: Risk of ischemic stroke predicted by baseline levels of sVCAM- 1, NT-proBNP, C-reactive protein, homocysteine, renin, and lipids and lipoprotein particle concentration and size. Results: Levels of sVCAM- 1 and NT-proBNP predicted recurrent ischemic stroke. The odds ratio for patients in the highest, as compared with the lowest, quarter was 2.24 (95% confidence interval, 1.35- 3.73) for sVCAM- 1 level and 1.62 (95% confidence interval, 0.98- 2.69) for NT-proBNP level, after adjustment for matching and other risk factors. Patients in the highest quarters for both sVCAM- 1 and NT-proBNP levels had 3.6 times the risk of recurrent ischemic stroke compared with patients in the lowest quarters for both biologic markers. Level of sVCAM- 1 was similarly predictive of ischemic stroke in patients allocated to placebo and perindopril-based therapy. Baseline plasma levels of C-reactive protein, homocysteine, renin, and lipids and lipoprotein particle concentration and size did not predict recurrent ischemic stroke risk. Conclusion: Measurement of sVCAM- 1 and NT-proBNP levels provides prognostic information for recurrent ischemic stroke beyond traditional risk factors.展开更多
文摘The potential felt by a single electron within a molecule represents the total interaction energy of this electron with all nuclei and the rest electrons in the molecule and is an important quantity. It is formulated and then calculated by using the ab initio MELD program plus a separate calculation program. We have systematically investigated and discussed this kind of potentials for a series of molecules. In terms of the three dimensional graph, the variation of the potential acting on the single electron within a molecule has clearly and visually been shown, and hence the electronic movement and the chemical bonding can be deeply understood.
文摘Background: Patients with stroke or transient ischemic attack are at high risk of another stroke, and there is need for improved strategies to predict recurrent stroke. Objective: To assess the prognostic value of levels of soluble vascular cell adhesion molecule 1 (sVCAM- 1), N-terminal pro-B-type natriuretic peptide (NT-proBNP), C-reactive protein, homocysteine, renin, and lipids and lipoprotein particle concentration and size in patients with previous stroke or transient ischemic attack. Design, Setting, and Participants: A nested case-control study of participants of the Perindopril Protection Against Recurrent Stroke Study was performed. The Perindopril Protection Against Recurrent Stroke Study was a placebo-controlled trial of a perindopril erbumine-based, blood pressure-lowering regimen that reduced ischemic stroke risk by 24% among individuals with previous stroke or transient ischemic attack. Each of 252 patients who experienced ischemic stroke during a mean follow-up of 3.9 years was matched to 1 to 3 control patients. Matching variables were age, sex, treatment allocated, region, and most recent qualifying event at randomization. Main Outcome Measures: Risk of ischemic stroke predicted by baseline levels of sVCAM- 1, NT-proBNP, C-reactive protein, homocysteine, renin, and lipids and lipoprotein particle concentration and size. Results: Levels of sVCAM- 1 and NT-proBNP predicted recurrent ischemic stroke. The odds ratio for patients in the highest, as compared with the lowest, quarter was 2.24 (95% confidence interval, 1.35- 3.73) for sVCAM- 1 level and 1.62 (95% confidence interval, 0.98- 2.69) for NT-proBNP level, after adjustment for matching and other risk factors. Patients in the highest quarters for both sVCAM- 1 and NT-proBNP levels had 3.6 times the risk of recurrent ischemic stroke compared with patients in the lowest quarters for both biologic markers. Level of sVCAM- 1 was similarly predictive of ischemic stroke in patients allocated to placebo and perindopril-based therapy. Baseline plasma levels of C-reactive protein, homocysteine, renin, and lipids and lipoprotein particle concentration and size did not predict recurrent ischemic stroke risk. Conclusion: Measurement of sVCAM- 1 and NT-proBNP levels provides prognostic information for recurrent ischemic stroke beyond traditional risk factors.
