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We evaluated 91 episodes of fever in 46 profoundly neutropenic children with cancer, in a search for any symptom, sign or laboratory test that would serve to identify patients with septicemia and differentiate them from those in no immediate need of prompt antimicrobial therapy. Seventeen episodes (19%) were bacteremias, 59 (64%) were suspected septic infections, 9 (10%) were focal bacterial infections and 6 (7%) proved not to be bacterial infections. We were unable to detect any parameter, either on admission or after two days of antimicrobial therapy (except for blood culture findings), that would be helpful in differentiating bacteremia from an episode not of bacterial origin. We focused on serum levels of C reactive protein and found them unreliable on an individual level. Prompt institution of antimicrobial therapy at the occurrence of fever results in low mortality, but does not allow assignment of cases to different categories.  相似文献   
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The dramatic expansion of clinical gene therapy trials requires the development of noninvasive clinical monitoring procedures, which provide information about expression levels, expression kinetics, and spatial distribution of transduced therapeutic genes. With the development of such procedures, invasive sampling of tissue probes from patients potentially could be reduced significantly. In this study, an experimental platform for the rational design and in vitro testing of suitable receptor-ligand couples as components of future transduction tag systems for noninvasive gene therapy monitoring applications was developed. Initially, the feasibility of the delta LNGFR/nerve growth factor (NGF) transduction tag system was investigated; this system employs a mutated version of the low-affinity nerve growth factor receptor (p75mut or delta LNGFR) lacking the entire cytoplasmic domain. Specific binding of 125I-radiolabeled NGF was demonstrated for two stable delta LNGFR-transduced cell lines, but not for delta LNGFR-negative parental control cell lines. An additional binding analysis performed in a MicroImager directly confirmed binding of radiolabeled ligands (125I-NGF, 125I-anti-p75 monoclonal antibody) to the p75mut expressed on intact target cells, but not on control cells. Subsequent binding studies employing NGF radiolabeled with the positron-emitting isotope 124I demonstrated a specific binding for LNGFR+ PC12 cells. Consequently, the first in vitro proof of a transduction tag approach based on the specificity of the 124I-NGF/LNGFR interaction was provided, which opens up the possibility for future noninvasive positron emission tomography monitoring in clinical gene therapy trials.  相似文献   
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Orbital trauma.     
In this review, a number of current issues on the management of orbital trauma are discussed including the indications for orbital exploration in zygomatic complex fractures, the utility of transantral endoscopy in orbital trauma surgery, and preferred implant materials in orbital reconstruction. We emphasize the need for a classification system to define some of the clinical terms used in describing orbital trauma, to improve communication between clinical services, and to standardize the clinical literature on orbital trauma.  相似文献   
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Anatomic limitations of balloon atrial septostomy   总被引:1,自引:0,他引:1  
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The purpose of this prospective, multicenter trial was to evaluate the safety and effectiveness of the TRAP Vascular Filtration System (VFS) to reduce embolic complications during stenting of diseased saphenous vein grafts (SVGs). Patients with SVG lesions were randomly assigned to undergo stenting with or without the TRAP device. The trial was designed to enroll 752 randomized patients. However, the sponsor terminated the study after a total of 467 patients (358 randomized) were enrolled because of poor recruitment once another distal protection device was approved for clinical use. The primary study endpoint, major adverse cardiac events at 30 days, occurred in 17.3% of control patients and 12.7% of patients treated with the TRAP device (P = 0.24). There was a trend toward a lower incidence of myocardial infarction in the TRAP group compared with the control group (16.2% vs 10.5%, P = 0.12). This difference was predominantly due to a lower incidence of moderate-large infarction (CKMB >5x) in the TRAP group. Use of the TRAP VFS during SVG intervention was safe and was associated with a trend toward a lower incidence of adverse events, however, due to low enrollment the study lacked sufficient power to detect a significant benefit with the device.  相似文献   
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