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Breast cancer detection: one versus two views   总被引:2,自引:0,他引:2  
Mammographic examinations of 169 patients with 172 biopsy-proved carcinomas, and of 194 healthy subjects, were interpreted independently and retrospectively by three experienced mammographers, initially as single-view oblique examinations and 6 months later as two-view oblique-cephalocaudal examinations. For the single-view examinations of the cancer patients, 67% of the cancers were correctly recommended for biopsy, additional views were requested for 23%, and a "negative" interpretation was made for 10%. For the single-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were recommended for 32%. For the two-view examinations of women with cancer, 80% of the cancers were correctly recommended for biopsy, additional views were requested for 4%, and a "negative" interpretation was made for 16%. For two-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were requested for only 5%. The authors conclude that single-view screening should not be performed, because it would lead to an excessive number of "call-back" examinations of healthy patients, producing additional cost and anxiety that would outweigh any theoretical benefit.  相似文献   
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Purpose

To present the first photographed bronchoscopic findings associated with negative pressure pulmonary oedema (NPPE).

Clinical features

A previously healthy patient underwent anterior C3–C4 disc removal and arthrodesis. Following tracheal extubation he developed acute respiratory distress manifested as stridor, tachypnoea, restlessness, and desaturation. Once the trachea was reintubated, he displayed the classic findings of pulmonary oedema. Bronchoscopy was performed to confirm tracheal tube position and to rule out tracheal injury secondary to surgical manipulation. Diffuse punctate haemorrhages were noted throughout the visualised tracheobronchial tree.

Conclusion

We believe that these haemorrhages represent disruption of the bronchial vasculature and may contribute to the clinical presentation of NPPE.  相似文献   
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Wheat, barley, and maize, each in 15-kg parcels at 15 and 19% initial moisture content (IMC), were kept in a Bavarian farm granary from June through November 1990. During this period, the grain at each IMC was analyzed for mycotoxins and monitored for grain temperature, carbon dioxide, seed germination, and microfloral incidence and abundance. Barley and maize stored for 20 weeks at 19% IMC contained ochratoxin A in amounts of 70 and 90 g/kg, respectively. This mycotoxin was not detected in wheat stored at 19% IMC, nor in the grains stored at 15% IMC. Aflatoxin B1, sterigmatocystin, citrinin, and zearalenone were also assayed but not detected in grains stored at either IMC. Principal component analysis of the data indicated that ochratoxin A was produced in a damp niche in maize, when abundant metabolic activity and CO2 production by Penicillium glandicola and Aspergillus spp. were common.Contribution No. 1476 of the Agriculture Canada Research Station.  相似文献   
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Otospongiosis-like lesions were induced in rats by immunizing them with type II collagen. After seven months' immunization, the rats were killed and processed for histologic study. We found otospongiotic lesions in the bony cochlea, vestibule, semicircular canal, and in the regions near the oval window and round window. The spongiotic lesions in the otic capsules were similar to human otospongiosis and were characterized by the following types of microscopic appearances. 1) The classic type showed enlarged vascular spaces with congestion, macrophages, fibroblasts, and sometimes osteoclasts. 2) The fibrotic type showed vascular spaces filled with fibrous tissues. 3) The osteoporotic type had a porous appearance and was devoid of content. 4) The sclerotic type showed bone spaces partially or entirely being replaced by new bone with blue mantles and a mosaic appearance. Some spongiotic lesions showed a mixture of the above types. The findings suggest that this animal model may provide important information to help understand the process of human otosclerosis.  相似文献   
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Background  

The aims of this study were to evaluate contemporary outcomes associated with the surgical management of pancreatic neuroendocrine tumors (PNETs) and to assess the prognostic value of the World Health Organization (WHO) classification and TNM staging for PNETs.  相似文献   
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