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Eleven children with Pseudomonas aeruginosa infection complicating foot puncture wounds were reviewed. Delay in presentation (mean 2 days) and diagnosis (mean 9 days) due to a paucity of clinical signs of deep infection was characteristic of this condition. Septic arthritis (5 patients) and osteomyelitis (3 patients) were frequent complications. Treatment involved multiple surgical debridements and prolonged intravenous antibiotic therapy. The clinical outcome was good although long-term radiographic changes were common.  相似文献   
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Five out of 12 physically healthy patients with depression undergoing a tyramine pressor test developed cardiac arrhythmias. These arrhythmias occurred in drug-free patients in three out of 12 infusions following as little as 0.03 mg/kg of tyramine and after moclobemide, a reversible inhibitor of monoamine oxidase-A, in four out of 14 tyramine infusions with as little as 0.04 mg/kg of tyramine. The arrhythmias seen were independent of patient's age and occurred both before and after 30 mmHg elevations in systolic blood pressure. Electrocardiographic abnormalities and arrhythmias seen were a loss of p waves, sinus tachycardia, frequent atrial ectopic beats, atrial premature beats, Wenckebach phenomenon, junctional rhythm, ventricular ectopics, varying QRS configurations, and ventricular bigeminy. Tyramine, both oral and intravenous, caused similar reproducible changes in dogs, though not in rats, mice or guinea pigs. Practical implications are that tyramine pressor testing in humans should be performed cautiously and only with adequate cardiac monitoring and resuscitation facilities at hand. These findings suggest that a normal dietary component can induce serious cardiac arrhythmias, and that a low-tyramine diet may be of value for patients who are susceptible to cardiac arrhythmias.  相似文献   
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A vertically integrated health care system is an arrangement whereby a health care organization offers, either directly or through others, a broad range of patient care and support services. This article discusses the market forces and strategic considerations driving the recent trend toward vertical linkages in health care markets and examines some of the managerial implications and issues associated with this vertical restructuring trend.  相似文献   
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The axon terminals of cone horizontal cells in the goldfish retina form typical chemical synaptic contacts in the middle of the inner nuclear layer. Approximately 60% of the identified postsynaptic elements were perikarya, axons and dendrites of bipolar cells. The other identified postsynaptic elements were perikarya and processes of interplexiform cells. We propose that the horizontal cell axon terminal contribute to the antagonistic surround responses of the bipolar cells and that they modulate inputs to the outer plexiform layer conveyed by interplexiform cells. Output synapses from horizontal cell axons to unidentified neuronal processes as well as occasional input synapses to the axons from interplexiform cell processes and unidentified perikarya were also observed in the same region of the inner nuclear layer.  相似文献   
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Chitambar  CR; Zivkovic  Z 《Blood》1989,74(2):602-608
Information regarding transferrin (Tf) receptor degradation is largely incomplete. HL60 cells were shown to release to their growth medium a Tf-binding protein which could be immunoprecipitated by anti-Tf receptor monoclonal antibodies (MoAbs) B3/25 and OKT9. Soluble Tf receptor was detected in the medium within one hour of replating of cells, and its release was inhibited at 4 degrees C. The affinity of Tf for the soluble receptor released by cells (kd = 2.3 x 10(-10) mol/L) was slightly lower than its affinity for the detergent-solubilized cellular receptor (kd = 1.2 x 10(-10) mol/L). 125I-Tf internalized and released by cells subsequently bound to Tf receptor released by the same cells, and soluble Tf receptor in the conditioned medium (CM) inhibited 125I-Tf binding to intact cells. The soluble Tf receptor isolated from the CM was smaller (78,000 daltons) than the cell surface receptor (94,000 daltons) when analyzed by gel electrophoresis under reducing conditions. Isolated cell membranes readily released soluble receptor; however, this release could be blocked by protease inhibitors. The soluble Tf receptor may represent the extracytoplasmic domain of the cellular Tf receptor released from the surface of HL60 cells through proteolytic cleavage by a membrane-based protease.  相似文献   
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Advances in endoscopic surgical equipment and laser technology have expanded the role of thoracoscopy to include thoracoscopic pulmonary resection. Eighty-five thoracoscopic pulmonary resections were performed on 61 consecutive patients with small lesions (less than 3 cm) in the outer third of the lung. Patients with preoperative histologic evidence of bronchogenic carcinoma were excluded unless there was impairment of cardiopulmonary function, advanced age, or concomitant extrathoracic malignancy. These thoracoscopic pulmonary resections were accomplished with the neodymium:yttrium-aluminum garnet laser (31), endoscopic stapler (29), or both (25). The mean diameter of the lesions was 1.3 cm (range, 0.4 to 2.7 cm). There has been one late death (38th postoperative day) unrelated to the operation. Morbidity consisted of postoperative atelectasis (2), pneumonia (2), bleeding requiring transfusion (1), and bronchopleural fistula of greater than 7 days duration (3). There were no wound problems. The mean period of chest tube drainage was 3.3 +/- 3.0 days. Mean postoperative stay was 5.7 +/- 4.9 days. The pathologic diagnosis was benign disease in 28 patients (interstitial fibrosis/pneumonitis, 15; radiation fibrosis, 1; sclerosing hemangioma, 1; rheumatoid nodules, 1; granuloma, 2; nocardia, 1; infarct, 1; hamartoma, 4; scar, 1; cytomegalovirus pneumonia, 1), metastatic malignancy in 20 patients, and bronchogenic carcinoma in 13 patients. Five patients found at thoracoscopic pulmonary resection to have bronchogenic cancer had adequate pulmonary function and therefore underwent formal segmentectomy (3) or lobectomy (2). Thoracoscopic pulmonary resection was the only operation performed on patients with benign disease, patients with metastatic lesions, and selected patients with limited stage bronchogenic carcinoma at increased risk for thoracotomy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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