Annals of internal medicine
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Review Clinical Trial
Wegener's granulomatosis: prospective clinical and therapeutic experience with 85 patients for 21 years.
Eighty-five patients with Wegener's granulomatosis were studied for 21 years at the National Institutes of Health. Patients were treated with a protocol consisting of cyclophosphamide, 2 mg/kg body weight d, together with prednisone, 1 mg/kg body weight d, followed by conversion of the prednisone to an alternate-day regimen. ⋯ Twenty-three patients are off all therapy for a mean duration of 35.3 (+/- 6.3) months without therapy. This study provides a prospective experience with Wegener's granulomatosis and shows that long-term remissions can be induced and maintained in an extremely high number of patients by the combination of daily cyclophosphamide and alternate-day prednisone therapy.
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The principal function of erythrocytes is the transport of oxygen. Erythropoiesis proceeds at a rate consistent with the demand for oxygen-carrying capacity, and the major regulator of erythrocyte production is erythropoietin. Erythropoietin is produced primarily by the kidney under control of a tissue oxygenation sensor. ⋯ Erythrocytosis increases oxygen-carrying capacity of the blood, but at high hematocrit levels increased blood viscosity may result in decreased tissue oxygen delivery. Polycythemia vera is a hematopoietic stem cell disease of clonal origin. Initial results from the Polycythemia Rubra Study Group suggest that therapy with chlorambucil is associated with an unacceptably high risk for development of acute leukemia, and 32P is preferred for situations in which phlebotomy alone is insufficient.
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The products of oxygen reduction (superoxide anion, hydrogen peroxide, hydroxyl radicals) and excitation (singlet oxygen) have been implicated in the toxic properties of phagocytes (neutrophils, eosinophils, and mononuclear phagocytes). Enzymes that potentiate (such as peroxidase) or limit (such as catalase, superoxide dismutase) the toxicity of these agents contribute to the complexity of the oxygen-dependent antimicrobial systems of phagocytes. These toxic systems are dormant when the phagocyte is at rest but are activated when the need arises and directed to the destruction of invading microorganisms and other foreign cells. Occasionally, the toxic systems are directed against normal host cells and in this way contribute to the pathogenesis of disease.
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Review Comparative Study
Quality of patient care by nurse practitioners and physician's assistants: a ten-year perspective.
A remarkable development in primary care is the recent emergence of a new class of health professional: nurse practitioners and physician's assistants. These practitioners diagnose and treat a wide variety of medical problems, usually with supervision by physicians. ⋯ These studies show that nurse practitioners and physician's assistants provide office-based care that is indistinguishable from physician care. Because these studies were limited in scope, there is no experimental basis for extending this conclusion to care given outside the office, care that is unsupervised, or care of the seriously ill patient.