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Since the introduction of the Orphan Drug Act in 1983, designed to promote development of treatments for rare diseases, at least 378 orphan drugs have been approved. Incentives include financial support, tax credits, and perhaps most importantly, extended market exclusivity. These incentives have encouraged industry interest and accelerated research on rare diseases, allowing patients with orphan diseases access to treatments. However, extended market exclusivity has been associated with unacceptably high drug costs, both for newly developed drugs and for drugs that were previously widely available. We suggest that a paradoxical effect of orphan product exclusivity can be reduced patient access to existing drugs. In addition, the costs of each new drug are arguably unsustainable for patients and for the American health care system. Of all the specialties, neurology has the third highest number of orphan product designations, and neurological diseases account for at least one‐fifth of rare diseases. Citing the use of tetrabenazine for chorea in Huntington disease, adrenocorticotropic hormone for infantile spasms, and enzyme replacement therapy with alglucosidase alpha for Pompe disease, we highlight these paradoxical effects. ANN NEUROL 2012;72:481–490  相似文献   
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This article examines the risk of proliferation of nuclear weapons to several Third World countries, exemplified by recent events in Iraq, and the possibility of rapid acquisition of a nuclear weapons capability in developed countries. It considers the role of the International Atomic Energy Agency and the United Nations in preventing proliferation and calls for wider powers for the latter. The role of the civil nuclear power industry and of reprocessing of nuclear fuel to produce plutonium is stressed, with emphasis on the part played by nuclear power in Japan and the THORP reprocessing plant at Sellafield.  相似文献   
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JOHNSON M., COWIN L.S., WILSON I. & YOUNG H. (2012) Professional identity and nursing: contemporary theoretical developments and future research challenges. International Nursing Review Aim: We propose that the conceptual orientation of professional identity is a logical consequence of self‐concept development by focusing on career and its meaning and presents a measurable set of concepts that can be manipulated to improve retention of student and registered nurses within health service. Background: Although professional identity is a term that is commonly written of in nursing literature, its theoretical origins remain unclear, and available empirical evidence of its presence or ability to change is omitted from nursing research. Sources of evidence: We present a professional identity pathway and explore the factors that influence professional identity throughout a career in nursing. Discussion: Nurses' professional identities develop throughout their lifetimes, from before entering nursing education, throughout their years of study and clinical experience, and continue to evolve during their careers. Education is, however, a key period as it is during this time students gain the knowledge and skills that separate nurses as professional healthcare workers from lay people. Conclusion: Finally, a call for longitudinal studies of students to graduates, using conceptually derived and psychometrically proven instruments capable of detecting the subtle changes in the construct over time, is recommended. Further empirical research into the theoretical concepts that underline professional identity, and the factors that influence changes in this important construct in nursing, is required. Ultimately, the practical relevance of such research will lie in the potential it provides for enhanced nursing career support and improved workforce policies.  相似文献   
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Spontaneous papillary muscle rupture (PMR) is a rare cardiovascular emergency. We present a 63‐year‐old male who presents with acute dyspnea who was found to have an anterior PMR, with no evidence of coronary artery disease, infection, or trauma. A review of cases of nonischemic spontaneous PMR published in 2000–2015 identified 11 additional cases of spontaneous PMR. Posterior and anterior papillary muscles involvement was identified in 54.5% and 45.5% of cases, respectively. Rapid identification due to advances in imaging modalities and improved surgical management has led to optimal outcomes in patients with spontaneous PMR.  相似文献   
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This review examines some of the advances in understanding myoclonus over the last 25 years. The classification of myoclonus into cortical, brainstem, and spinal forms has been consolidated, each with distinctive clinical characteristics and physiological mechanisms. New genetic causes of myoclonus have been identified, and the molecular basis of several of these conditions has been discovered. It is increasingly apparent that disease of the cerebellum is particularly important in the genesis of cortical reflex myoclonus. However, the precise mechanism and origin of myoclonus in many situations remain uncertain. Effective treatment of myoclonus remains limited, and the challenge lies ahead to develop more therapeutic options. © 2011 Movement Disorder Society  相似文献   
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