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Pathophysiology and treatment of diabetic erectile dysfunction 被引量:26
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作者 charles r.moore 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第6期675-684,共10页
The pathophysiology of diabetes is multifactorial and no single etiology is at the forefront. The proposed mechanisms of erectile dysfunction (ED) in diabetic patients includes elevated advanced glycation end-produc... The pathophysiology of diabetes is multifactorial and no single etiology is at the forefront. The proposed mechanisms of erectile dysfunction (ED) in diabetic patients includes elevated advanced glycation end-products (AGEs) and increased levels of oxygen free radicals, impaired nitric oxide (NO) synthesis, increased endothelin B receptor binding sites and ultrastructural changes, upregulated RhoA/Rho-kinase pathway, NO-dependent selective nitrergic nerve degeneration and impaired cyclic guanosine monophosphate (cGMP)-dependent kinase-1 (PKG-1). The treatment of diabetic ED is multimodal. Treatment of the underlying hyperglycemia and comorbidities is of utmost importance to prevent or halt the progression of the disease. The peripherally acting oral phosphodiesterase type 5 (PDE5) inhibitors are the mainstay of oral medical treatment of ED in diabetics. Vacuum erection devices are an additional treatment as a non-invasive treatment option. Local administration of vasoactive medication via urethral suppository or intracorpora! injection can be effective with minimal side-effects. Patients with irreversible damage of the erectile mechanism are candidates for penile implantation. Future strategies in the evolution of the treatment of ED are aimed at correcting or treating the underlying mechanisms of ED. With an appropriate vector, researchers have been able to transfect diabetic animals with agents such as neurotrophic factors and nitric oxide synthase (NOS). Further studies in gene therapy are needed to fully ascertain its safety and utility in humans. 展开更多
关键词 erectile dysfunction DIABETES MECHANISM treatment
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倾斜转弯导弹的次优制导规律
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作者 Romesh K.Aggarwal charles r.moore 陈渊 《上海航天》 1989年第1期16-23,共8页
倾斜转弯(BTT)导弹的非线性的俯仰和偏航动态耦合,是由导弹的侧向加速度和倾斜角引起的。由于这些非线性动态特性,最优加速度和倾斜速率指令的解只能通过两点边值问题求解的数值方法得到。具体实现时,必须有相应于现行系统状态其它部分... 倾斜转弯(BTT)导弹的非线性的俯仰和偏航动态耦合,是由导弹的侧向加速度和倾斜角引起的。由于这些非线性动态特性,最优加速度和倾斜速率指令的解只能通过两点边值问题求解的数值方法得到。具体实现时,必须有相应于现行系统状态其它部分的动态过程,最优控制问题的解可以用扰动技术得到,这种技术根据能解的降阶问题的解,然后规定降阶解组合成全阶问题的近似解的方法,把系统分成慢速和快速状态。这种技术过去已被用于飞机和导弹弹道最优问题,可是这个问题的表述与其他问题不同。因为小扰动系数是滚动控制代价的加权因子。这样当这参数较小时,滚动控制代价也变得非常小,即这问题看成是"经济控制"问题。合成解由作为现行系统状态函数的滚动速率和加速度指令组合,"零阶慢速"解是侧滑转弯导弹的最优制导律。认为滚动速率无限快,忽略导弹倾斜角的动态情况可有效地获得这个解。"零阶快速"解提供滚动指令,这被认为是补偿倾斜角有限动态特性的校正项。慢速解需要一个"一阶"校正项,通常这一项用扰动理论来获得。但是对于这个问题,一个恰当"慢速"解能通过最优条件来得到,在仿真比较中,利用反向扫描方法可获得最优解,结果表明,BTT 导弹的"次优制导规律"是有效的。 展开更多
关键词 导弹制导 次优制导规律 倾斜转弯
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