Objective: To examine the effects of nifedipine GITS on clinical outcome in patients with concurrent stable angina and hypertension. Methods: Data from the double-blind placebo-controlled ACTION trial was stratified f...Objective: To examine the effects of nifedipine GITS on clinical outcome in patients with concurrent stable angina and hypertension. Methods: Data from the double-blind placebo-controlled ACTION trial was stratified for hypertension(blood pressure ≥140/90 mmHg), at baseline. Results: A total of 52%of 7665 ACTION patients were hypertensive. Some 80%were on a βblocker; hypertensives were more often treated with other blood pressure-lowering drugs. Mean baseline blood pressure was 122/74 mmHg among normotensives and 151/85 mmHg among hypertensives. Follow-up blood pressures were reduced by nifedipine(P< 0.001) on the average by 3.9/2.4 and 6.6/3.5 mmHg among normotensives and hypertensives, respectively. Nifedipine GITS significantly(P< 0.05) reduced the combined incidence of all-cause mortality, myocardial infarction, refractory angina, heart failure, stroke and peripheral revascularization by 13%in hypertensives only. Nifedipine significantly reduced the incidence of any stroke or transient ischemic attack by almost 30%in both subgroups and the need for coronary angiography by 21%in normotensives and 16%in hypertensives. Among hypertensives, the incidence of new overt heart failure was significantly reduced by 38%and of debilitating stroke by 33%. Among normotensives, the need for coronary bypass grafting was significantly reduced by 32%. Nifedipine did not affect all-cause death, cardiovascular death and myocardial infarction in either normo-or hypertensives, but increased the need for peripheral revascularization. Conclusion: The salutary effects of the addition of nifedipine GITS to the basic regimen of patients with concurrent stable symptomatic coronary artery disease and hypertension emphasize the need for blood pressure control.展开更多
A new approach to dynamic modeling based on a discrete-imitation concept has been developed.The fundamentals,including terms and principles of the concept,have been explained.The presented concept has been applied to ...A new approach to dynamic modeling based on a discrete-imitation concept has been developed.The fundamentals,including terms and principles of the concept,have been explained.The presented concept has been applied to the integrated modeling of the development of a volatile oil reservoir operated by a sucker-rod pumping well within a pump-well-reservoir system.The discrete-imitation model of the“pump-well-reservoir”system,developed based on the principles of the new concept,takes into account fluid flow between the annulus and the lifting bore.It was employed to investigate the operation of the sucker-rod pumping well.The correlation between pumping rate,pump fillage,and stroke speed has been investigated.It was observed that,as the stroke speed increases,both pump performance and pump fillage increase up to a certain point.Beyond this threshold,the pumping rate stabilizes,and the pump fillage experiences a sharp decline.Notably,the maximum pump fillage does not always align with the peak pumping rate.In such instances,achieving an optimal regime is possible only through intermittent pumping.An expression has been derived to determine the optimal pump idle time in intermittent mode.展开更多
文摘Objective: To examine the effects of nifedipine GITS on clinical outcome in patients with concurrent stable angina and hypertension. Methods: Data from the double-blind placebo-controlled ACTION trial was stratified for hypertension(blood pressure ≥140/90 mmHg), at baseline. Results: A total of 52%of 7665 ACTION patients were hypertensive. Some 80%were on a βblocker; hypertensives were more often treated with other blood pressure-lowering drugs. Mean baseline blood pressure was 122/74 mmHg among normotensives and 151/85 mmHg among hypertensives. Follow-up blood pressures were reduced by nifedipine(P< 0.001) on the average by 3.9/2.4 and 6.6/3.5 mmHg among normotensives and hypertensives, respectively. Nifedipine GITS significantly(P< 0.05) reduced the combined incidence of all-cause mortality, myocardial infarction, refractory angina, heart failure, stroke and peripheral revascularization by 13%in hypertensives only. Nifedipine significantly reduced the incidence of any stroke or transient ischemic attack by almost 30%in both subgroups and the need for coronary angiography by 21%in normotensives and 16%in hypertensives. Among hypertensives, the incidence of new overt heart failure was significantly reduced by 38%and of debilitating stroke by 33%. Among normotensives, the need for coronary bypass grafting was significantly reduced by 32%. Nifedipine did not affect all-cause death, cardiovascular death and myocardial infarction in either normo-or hypertensives, but increased the need for peripheral revascularization. Conclusion: The salutary effects of the addition of nifedipine GITS to the basic regimen of patients with concurrent stable symptomatic coronary artery disease and hypertension emphasize the need for blood pressure control.
文摘A new approach to dynamic modeling based on a discrete-imitation concept has been developed.The fundamentals,including terms and principles of the concept,have been explained.The presented concept has been applied to the integrated modeling of the development of a volatile oil reservoir operated by a sucker-rod pumping well within a pump-well-reservoir system.The discrete-imitation model of the“pump-well-reservoir”system,developed based on the principles of the new concept,takes into account fluid flow between the annulus and the lifting bore.It was employed to investigate the operation of the sucker-rod pumping well.The correlation between pumping rate,pump fillage,and stroke speed has been investigated.It was observed that,as the stroke speed increases,both pump performance and pump fillage increase up to a certain point.Beyond this threshold,the pumping rate stabilizes,and the pump fillage experiences a sharp decline.Notably,the maximum pump fillage does not always align with the peak pumping rate.In such instances,achieving an optimal regime is possible only through intermittent pumping.An expression has been derived to determine the optimal pump idle time in intermittent mode.
