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Hospitalized neonates are commonly colonized soon after birth with Staphylococcus aureus. The majority of neonates do not develop infectious sequelae; however, premature neonates appear to be more susceptible to serious infections, such as pneumonia. We report a case of an extremely low birth weight infant who developed necrotizing pneumonia due to methicillin-resistant Staphylococcal aureus (MRSA). The MRSA isolate from this neonate is identical to the strains that have been causing primarily community-associated skin and soft tissue infections. The severe course of this patient may be attributed to the presence of the Panton-Valentine leukocidin gene, a well-known virulence factor leading to soft tissue and pulmonary infections.  相似文献   
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Perioperative haemotherapy: I. Indications for blood component transfusion   总被引:2,自引:0,他引:2  
The practice of transfusion medicine has undergone substantial change over the last decade. Much of the impetus for the change has come from the isolation of human immunodeficiency virus (HIV) and the linkage of HIV transmission to blood transfusion. The purpose of this paper is to collate and review the literature relating to the indications for blood transfusion and provide recommendations for the appropriate utilization of blood products. Peer-reviewed and published studies and reviews relating to aspects of clinical blood transfusion were identified through computer searches and searching of the bibliographies of identified articles. Emphasis was placed on the literature published within the last decade and particularly in the years 1985-91. Material was chosen which was of proved clinical importance and in which findings were consistent among different investigators or different centres. Less emphasis was placed on material reporting new findings of uncertain clinical relevance or findings that were not consistent with majority reports. It is concluded that the only indication for red cell transfusion is to increase the oxygen carrying capacity of the blood and that an adjustment downwards in the haemoglobin concentration at which blood is transfused (transfusion trigger) from the traditional level of 100 g.L-1 is supported by the physiological and clinical data. Perioperative haemoglobin concentrations of 80 g.L-1 are acceptable in otherwise healthy young patients. The transfusion trigger should be adjusted upwards from this in medically compromised patients and in the elderly (greater than 60 yr). Fresh frozen plasma (FFP) is only indicated when there are documented deficiencies of coagulation factors. Platelet concentrates (PC) are indicated for the treatment of clinical coagulopathy resulting from thrombocytopaenia or platelet dysfunction. Routine or prophylactic administration of either FFP or PC after cardiopulmonary bypass or during resuscitation from haemorrhage is not indicated.  相似文献   
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A new syndrome is described in a patient with advanced renal insufficiency. This consists of severe and persistent hypotension causing weakness but associated with a clear mental status. Also present is evidence for decreased vascular reactivity. The hypotension was not orthostatic. The hypotension was associated with a circulating vasodepressor substance having the characteristics of medullipin I. The medullipin appears to have been derived from the remaining right kidney. Hypotension existed despite the presence of major prohypertensive mechanisms, including an endstage kidney, hyperreninemia and hyperaldosteronemia. It is likely that hypotension due to hypermedullipinemia is an entity occurring in the human being.  相似文献   
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PURPOSE: The aim of this retrospective study was to analyze the characteristics of delayed panfacial fractures and evaluate treatment results. PATIENTS AND METHODS: Thirty-three patients with delayed panfacial fractures were treated in the Maxillofacial Trauma Center of Peking University, School and Hospital of Stomatology between 1998 and 2004. Each patient was examined by computed tomography (CT) scans before operation. For those who had no severe opening restriction, dental impressions were taken to fabricate dental casts. For those with severely comminuted fractures, 3-dimensional (3D) models of the facial skeleton were used. Re-establishing the continuity of the mandible was the first step and then used as a platform to reconstruct the maxillary fractures via maxillomandibular fixation after Le Fort I osteotomy. The third step was to restore the mid- and upper-facial width and projection by coronal approach to expose the zygomatic complex and frontal bone/sinus and/or naso-orbito-ethmoid (NOE) fractures. RESULTS: There were 3 types of mandibular fractures that affected the treatment plan: 1) type I, mandibular body/symphysis fracture(s) (17/33, 51.52%); 2) type II, mandibular angle and/or condylar fracture(s) (6/33, 18.18%); and 3) type III, both mandibular body/symphysis and angle/condylar fractures (10/33, 30.30%). Fourteen cases were associated with NOE fractures (42.42%) and 3 cases had frontal sinus fractures (9.1%). Twelve cases had enophthalmos (36.36%) and 3 lost 1 eyeball. The order of treatment was dependent on the mandibular fracture type. For type I fractures, reconstructing the mandibular arch was the first step. For type II fractures, repairing the angle, ascending rami, and condylar areas was the first step. For type III fractures, when both mandibular height and arch were disrupted, freeing the malunited angle or condyle was the first step before restoring the mandibular arch form. Reconstruction of the mandibular height and projection was then carried out. For all 3 types, the second step was to restore the mid- and upper facial width and projection by reducing the zygomatic complex and frontal bone/sinus or NOE fractures. Maxillary fixation across the Le Fort I level was the last step. Le Fort I osteotomy was used for all 33 cases. Bone grafts and soft tissue suspension also were used. Twenty-one cases (63.64%) had good results, 7 (21.21%) cases were acceptable, and 5 (15.15%) were not good. There were 7 cases (21.21%) that still had soft tissue problems that needed secondary operations. CONCLUSIONS: Reconstruction of the mandible first with Le Fort I osteotomy is a good way to treat delayed panfacial fractures. Computed tomography and 3D CT, model surgery, and occasionally 3D models are necessary aids for diagnosis and treatment. Soft tissue problems, including lacerations and asymmetries, were often the factors that caused an unfavorable outcome.  相似文献   
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