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Objective: To compare the sensitivities, specificities, and accuracies between a single-view ultrasonography (US) technique and a multiple-view technique for identifying hemoperitoneum in multiple-trauma patients.
Methods: Data from a prior prospective study of US for trauma diagnosis at a level I trauma center were retrospectively analyzed. A convenience sample of adult patients (≥ 18 years of age) who had presented with major blunt or penetrating torso trauma and had undergone rapid trauma US examinations to detect hemoperitoneum were reviewed. The US interpretations by emergency physicians had been recorded prior to obtaining other diagnostic tests. Five views were evaluated, including the right intercostal oblique view examining Morison's pouch. Evidence of free intraperitoneal fluid by exploratory laparotomy, CT, or diagnostic peritoneal lavage (DPL) was used as the criterion standard.
Results: Of the 245 patients entered into the study, 37 had free intraperitoneal fluid, confirmed by CT, DPL, or exploratory laparotomy. With the multiple-view technique, US was 87% (95% CI = 71%, 96%) sensitive, 100% (95% CI = 97%, 100%) specific, and 98% (95% CI = 95%, 100%) accurate. The single-view technique, evaluating only Morison's pouch, was 51% (95% CI = 34%, 68%) sensitive, 100% (95% CI = 98%, 100%) specific, and 93% (95%. CI = 89%, 96%) accurate.
Conclusions: An initial trauma US examination using a multiple-view technique is more sensitive than that using a single-view technique for detecting hemoperitoneum in trauma patients.  相似文献   
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A case of a 49-year-old patient with two superficial spreading melanomas arising from a naevus spilus is presented. Although opinions differ on the potential for malignant transformation in naevi spili, they should be carefully watched, and if changes are found these lesions should be subjected to histopathologic examination.  相似文献   
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Competitive control of the self-renewing T cell repertoire   总被引:1,自引:0,他引:1  
We develop a mathematical model for the self-renewing part of the T cell repertoire. Assuming that self-renewing T cells have to be stimulated by immunogenic MHC-peptide complexes presented on the surfaces of antigen-presenting cells, we derive a model of T cell growth in which competition for MHC-peptide complexes limits T cell clone sizes and regulates the total number of self-renewing T cells in the animal. We show that for a sufficient diversity and/or degree of cross-reactivity, the total T cell number hardly depends upon the diversity of the T cell repertoire or the diversity of the set of presented peptides. Conversely, for repertoires of lower diversity and/or cross-reactivity, steady-state total T cell numbers may be limited by the diversity of the T cells. This provides a possible explanation for the limited repertoire expansion in some, but not all, mouse T cell re-constitution experiments. We suggest that the competitive interactions described by our model underlie the normal T cells numbers observed in transgenic mice, germ-free mice and various knockout mice.   相似文献   
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Localization of a gene for otosclerosis to chromosome 15q25-q26   总被引:5,自引:0,他引:5  
Among white adults otosclerosis is the single most common cause of hearing impairment. Although the genetics of this disease are controversial, the majority of studies indicate autosomal dominant inheritance with reduced penetrance. We studied a large multi- generational family in which otosclerosis has been inherited in an autosomal dominant pattern. Five of16 affected persons have surgically confirmed otosclerosis; the remaining nine have a conductive hearing loss but have not undergone corrective surgery. To locate the disease- causing gene we completed genetic linkage analysis using short tandem repeat polymorphisms (STRPs) distributed over the entire genome. Multipoint linkage analysis showed that only one genomic region, on chromosome 15q, generated a lod score >2.0. Additional STRPs were typed in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis gene.   相似文献   
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