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The presenting manifestations of polycythemia vera are often complications involving the vascular system. These include myocardial infarction, cerebro-vascular accidents and ischemic changes in the extremities.The concept of increased atherogenesis in cases of polycythemia vera has been questioned. A possible mechanism by which small, otherwise subclinical atheromatous plaques produce ischemic symptoms in patients with polycythemia vera is discussed. The blood in polycythemic patients has been shown to have an increased viscosity resulting in a prolonged circulation time. If a small atheromatous plaque is present in association with increased blood viscosity, this combination may well produce ischemic symptoms. This explains why treatment of polycythemia vera, with restoration of blood to normal viscosity, often reverses the patient''s ischemic symptoms.Two cases of polycythemia vera here reported, in which the presenting manifestations were gangrenous extremities, emphasize the need for prompt diagnosis and treatment of polycythemia vera. In the first case, early recognition and treatment of polycythemia vera successfully reversed the ischemic changes in the extremities, while failure of early recognition and treatment in the second case resulted in two major amputations.  相似文献   
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RHINOVIRUSES AND RESPIRATORY DISEASE   总被引:2,自引:1,他引:1       下载免费PDF全文
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William Addleman 《CMAJ》1964,91(18):946-951
There is a proper time to advise removal of the colon and creation of a permanent ileostomy in the course of progressive toxic ulcerative colitis. When a thorough trial of medical therapy, including corticosteroids, has failed to halt progression of the disease, a properly timed colectomy may give the patient a new lease on life and enable him to maintain himself socially and economically.The development of ileostomy (Q-T) clubs has been an important factor in preparing them for and sustaining these young patients through the psychological trauma of an ileostomy. Two patients are described who illustrate the value of properly timed surgery and the contribution that ileostomy clubs can make.  相似文献   
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Atrial or ventricular myocardium from patients with surgically corrected rheumatic valvular disease was studied for rheumatic lesions in 86 cases. Histologically active Aschoff bodies were found in 20 per cent of the cases. A slight, but statistically not significant relationship was demonstrated in comparison of elevated serologic tests for rheumatic activity with the presence of Aschoff bodies.  相似文献   
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Anhidrotic ectodermal dysplasia in an inbred kindred was observed in three sisters and three first cousins. This was interpreted as presumptive evidence for autosomal recessive inheritance and it is suggested that in addition to its known genes, anhidrotic ectodermal dysplasia occasionally may be caused by an autosomal recessive gene.This investigation was supported by Public Health Service Research Grant No. FR 00123, from GCRC-DRFR and by a Fellowship in Pediatric Teratology of the Children's Hospital Research Foundation, Cincinnati.  相似文献   
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A study of 10 infants in severe metabolic acidemia (pH below 7) led to the conclusion that the clinical signs—hyperventilation, coma or lethargy, peripheral vascular collapse, a significantly palpable liver, and abdominal distension—may all be directly related to the metabolic acidemia. In five of 10 infants, an initial erroneous diagnosis of congestive heart failure or pneumonia was made. Dramatic clinical improvement followed correction of the acidemia with rapid intravenous administration of sodium bicarbonate. This rapid administration of sodium bicarbonate was safe, provided hypocalcemia was recognized and treated in its early stages. In severe metabolic acidemia the measurement of blood bicarbonate alone does not reflect adequately the magnitude of the acid-base derangement and repeated measurements of hydrogen ion concentration, Pco2 and bicarbonates are needed to evaluate and treat such infants correctly.  相似文献   
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