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71.
Neuroprotective therapies in glaucoma may play a role in preventing ischemia and oxidative damage that results in apoptosis of retinal ganglion cells and optic nerve damage. Although intraocular pressure (IOP) is the only known modifiable risk factor for glaucoma, disease progression commonly occurs despite IOP control, suggesting that factors other than IOP play a role in its pathogenesis and can potentially act as targets for neuroprotection. Factors including mediators of apoptosis, ischemic changes, poor ocular blood flow and neurotoxins have been hypothesized to play a role in glaucoma progression. Neuroprotective targets include glutamate-induced neurotoxicity, nitric oxidase synthetase, neurotropins, calcium channel receptors, free radicals, vascular insufficiency, the rho-kinase pathway, and more. Drugs related to these factors are being evaluated for their role in neuroprotection, although this area of investigation faces several challenges including limited evidence for these agents’ efficacy in clinical studies. Additionally, while IOP-lowering therapies are considered neuroprotective as they generally slow the progress of glaucoma progression, they are limited by the extent of their effect beyond IOP control. The aim of this article is to review the current treatment options available for neuroprotection and to explore the drugs in the pipeline.  相似文献   
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The dynamic stiffness matrix (DSM) method, an analytical method that provides exact solutions, has been used for the first time for the free vibration analysis of a functionally graded (FG) rotor bearing system subjected to temperature gradients and to investigate its application to FG rotors. The material gradation occurs based on the power law between the inner metal core and the outer ceramic rich layer of the FG rotor. The temperature gradation follows the Fourier law of heat conduction which leads to non-linear temperature distribution (NLTD) in the radial direction of the FG rotor. The development of the DSM formulations for Timoshenko FG rotor elements using the governing equations derived from translational and rotational equilibrium conditions is the novelty of the present work. The DSM of the FG rotor elements, rigid disk and linear isotropic bearings are assembled to obtain the global dynamic stiffness matrix of the FG rotor bearing system. The natural whirl frequencies are computed from the global DSM using the Wittrick–William algorithm as a root searching technique. The natural and whirl frequencies are validated with the results available in the literature and the exactness of the DSM method has been exemplified.  相似文献   
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Although tremendous progress has been made in conventional treatment for ischemic heart disease, it still remains a major cause of death and disability. Cell-based therapeutics holds an exciting frontier of research for complete cardiac recuperation. The capacity of diverse stem and progenitor cells to stimulate cardiac renewal has been analysed, with promising results in both pre-clinical and clinical trials. Mesenchymal stem cells have been ascertained to have regenerative ability via a variety of mechanisms, including differentiation from the mesoderm lineage, immunomodulatory properties, and paracrine effects. Also, their availability, maintenance, and ability to replenish endogenous stem cell niches have rendered them suitable for front-line research. This review schemes to outline the use of mesenchymal stem cell therapeutics for ischemic heart disease, their characteristics, the potent mechanisms of mesenchymal stem cell-based heart regeneration, and highlight preclinical data. Additionally, we discuss the results of the clinical trials to date as well as ongoing clinical trials on ischemic heart disease.  相似文献   
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Mild cognitive impairment (MCI) is associated with an increased risk of developing dementia. This is clinically relevant overt dementia can be prevented if treatment strategies are devised for MCI. Neuropsychological deficits in this condition are very common and are important clinically for treatment and outcomes. We aimed to review various neuropsychological deficits in MCI. Further, we have presented the current evidence for nosological status, neuroanatomical basis, and clinical outcome of this heterogeneous construct. All published papers on the topic of neuropsychological deficits in MCI on Medline and other databases were reviewed. A wide range of memory and executive function deficits are common in MCI patients. However, several studies are limited by either improper designs or inadequate sample sizes. Several neuropsychological impairments like memory function and executive functions can be diagnosed in MCI. The evidence base for the exact neuroanatomical basis of MCI is not robust yet. However, given the wide range of outcomes, controversies and debates exist regarding the nosological significance of the deficits. Hence, more studies are needed to specifically locate the impairments and further delineate the construct of MCI.  相似文献   
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