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41.
A 1 to 30 year follow-up study of 54 infants and children with paroxysmal supraventricular tachycardia is presented. In 28 cases the first attack occurred in infancy, and in 18 of these already in the first months of life. Nine patients had organic heart disease. The WPW syndrome was diagnosed in 30 cases. When first seen, most of the infants presented signs of incipient or manifest congestive heart failure, which was very unusual in the children, most of whom had only minor symptoms. Four children had experienced brief syncopes during attacks. Digitalis was effective against congestive heart failure and, when continued, may have prevented failure during subsequent attacks. Whether digitalis and other anti-arrhythmic agents facilitated conversion to sinus rhythm could not be established in this study. Vagal stimulation was only rarely effective. Preventive treatment with digitalis or other antiarrhythmic drugs seemed to have little if any effect on the frequency of recurrent attacks. Out of 23 infants who were followed for at least 5 years, 17 had been free from attacks during the last 3 years and 13 of these had had their last attack before the age of 6 months. Out of 23 children followed for 5 years or more, only 3 had been free from recurrences during the last 3 years. Patients with the WPW-syndrome had a somewhat higher incidence of recurrent attacks.  相似文献   
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The Harkness Fellowship in healthcare policy offers researchers and practitioners up to 12 months in the U.S. to conduct original research. Fellows include the late broadcaster Alistair Cooke and former Number 10 advisor Simon Stevens. A substantial grant is provided to cover airfare, living expenses, taxes and health insurance.  相似文献   
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As an alternative to performing interventional radiology on inpatients under the care of internists and surgeons, the authors have established a cardiovascular radiology admitting service for well-screened, elective patients. The patients are admitted under the care of a cardiovascular radiology fellow and a staff physician. From April 1982 to December 1983, 133 patients were admitted to the service. Patients are cared for in a surgical ward or in an intermediate unit, as determined by the clinical situation. Advantages of this approach include a broader patient referral base, improved rapport with clinical colleagues and patients, improved follow-up data, and rapid evaluation and treatment, resulting in short hospital stays. The major disadvantages involve the commitment of time and staff necessary to provide quality care. The concept of the interventional radiologist in the role of admitting physician has important implications in terms of negotiations for additional financial compensation, commensurate with the skill and time required for performing these procedures and caring for the patient.  相似文献   
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OBJECTIVES: This study examined the incremental cost-effectiveness of extending clopidogrel therapy from one month to one year after percutaneous coronary intervention (PCI) in an unselected, heterogeneous patient population. BACKGROUND: Clinical trials suggest that prolonging clopidogrel therapy for up to one year after PCI reduces downstream cardiac events. However, clopidogrel therapy is costly and may increase bleeding risk. METHODS: Using decision analysis, we compared the outcomes and cost of prolonging clopidogrel treatment from one month to one year after PCI with the alternative strategy of discontinuing therapy one month after the procedure. Event rates were based on 3,976 PCI patients who were treated between January 1999 and December 2001 at the Duke Medical Center and received no more than one month of clopidogrel after the procedure. Baseline characteristics and event rates were obtained from Duke clinical information systems. The effect of prolonged clopidogrel therapy on event rates was based on the Clopidogrel for the Reduction of Events During Observation (CREDO) trial per-protocol data. Unit costs and the effect of myocardial infarction (MI) on life expectancy were based on published sources. RESULTS: Extending clopidogrel therapy from one month to one year after PCI cost USD 879 per patient and reduced the risk of MI by 2.6%. Assuming MI decreases life expectancy by two years, prolonged therapy would cost USD 15,696 per year of life saved. Economic attractiveness of therapy varied with baseline risk, the effect of prolonged therapy on MI risk, and the price of clopidogrel. CONCLUSIONS: Prolonging clopidogrel therapy for one year after PCI is economically attractive, particularly in high-risk patients.  相似文献   
47.
BACKGROUND: Digital fibromas are common benign acral tumors typically reported as angiofibromas (AFs) or acquired digital fibrokeratomas (ADFs). Cellular variants are not well recognized. METHODS: We collected 14 acral fibrocytic lesions showing a spindle cell morphology from our files, and evaluated CD34, Factor XIIIa, epithelial membrane antigen (EMA), and S100 protein staining of these lesions. We compared the histologic and immunohistochemical features of these cellular fibromas with five digital AFs, five ADFs, and five digital dermatofibromas. RESULTS: The 14 cellular digital fibromas showed intersecting fascicles of thin delicate bland spindle cells in the superficial reticular dermis with a fibrotic-to-slight myxoid stroma. The spindle cells in all cases stained strongly for CD34, and only scattered stromal cells stained for Factor XIIIa. Five tested cases were negative for EMA and S100 protein. The digital AFs, fibrokeratomas, and dermatofibromas stained predominately for Factor XIIIa, with no or minimal staining for CD34. CONCLUSIONS: These findings suggest that a subset of digital fibromas is characterized by a dense cellular proliferation of CD34-positive spindle cells. Awareness of this variant of digital fibroma and its staining pattern is critical in preventing misdiagnosis as dermatofibrosarcoma protuberans, particularly in superficial biopsies.  相似文献   
48.
Interobserver variation in the interpretation of abdominal radiographs   总被引:2,自引:0,他引:2  
A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern.  相似文献   
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Solitary fibrous tumor (SFT) is an uncommon mesenchymal tumor that typically arises in the pleural cavity. Comprised of spindled cells characteristically arranged in diverse architectural patterns, SFT histologically simulates a variety of benign and malignant mesenchymal tumors. The diagnosis of SFT has been refined by the availability of newer immunohistochemical markers such as CD-34 and factor XIIIa, facilitating the identification of SFTs arising in multiple extrapleural sites, including the skin. We describe three cases of primary cutaneous SFT, review the literature, and discuss the histologic and immunohistochemical differential of other cutaneous tumors that SFT can mimic.  相似文献   
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