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J S Lindholt S Juul H Fasting E W Henneberg 《European journal of vascular and endovascular surgery》2006,32(1):9-15
BACKGROUND: The aim of this study was to estimate the cost effectiveness of screening for abdominal aortic aneurysm (AAA). MATERIAL AND METHODS: All 12,639 men born in the years 1921-1933 (aged 64-73) living in Viborg County, Denmark, were randomly allocated either to receive an invitation to abdominal ultrasound scanning for AAA or to be controls. Costs for screening and surveillance were assessed prospectively. Diagnosis Related Group (DRG) costs from 1999 were used concerning admissions with uncomplicated and complicated operations. Admissions for AAA surgery were retrospectively classified according to complications in patient records. RESULTS: Mean follow-up time was 52 months. 76.6% of invited men attended screening, and 191 (4.0%) had an AAA. As previously reported, the cumulative 5-year AAA-specific mortality in the invited group was significantly reduced by 67% compared to the control group (P = 0.003). The costs were estimated to be Euro 11.23 per scan. The costs per life-year saved were Euro 9057 (Euro 5872-20,063) after 5 years, and were expected to decrease to Euro 2708 (Euro 1758-6031) after 10 years and to Euro 1825 (Euro 1185-4063) after 15 years. CONCLUSION: Screening of 64-73 years old males in Denmark seems cost effective. 相似文献
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Samir K El-Mofty Sushama Patil 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,101(3):339-345
We have recently shown that HPV-positive tonsillar carcinoma in young patients exhibits nonkeratinizing basaloid morphology and a characteristic immunophenotype. The purpose of this study was to review a large number of cases of oropharyngeal carcinomas, in all age groups, and to identify tumors with nonkeratinizing morphology. Using polymerase chain reaction (PCR) the prevalence and type of HPV DNA was determined in representative cases and in a control group of conventional keratinizing squamous cell carcinomas. The tumors were further characterized with a panel of immunohistochemical stains. A total of 235 carcinomas were reviewed; 141 of the tonsils and 94 in the base of tongue. Ninety (36%) of the tonsillar and 30 (32%) of the base of tongue carcinomas were nonkeratinizing (NKCa) with basal cell features; the rest were classical keratinizing squamous cell carcinomas (KSCC). HPV DNA, particularly type 16, was identified in 10 (100%) of 10 of NKCA and in only 2 (20%) of 10 of KSCC (P = .0014). NKCas were strongly reactive to p16 antibodies while KSCC showed weak and focal reactivity. Higher Ki67 and lower p53 staining scores were observed in NKCa as compared to KSCC. It is concluded that NKCa of the tonsils and base of tongue is a distinct subtype of squamous cell carcinoma of the head and neck with high prevalence of HPV DNA and a characteristic immunophenotype. 相似文献
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F. Spöler M. Först Y. Marquardt D. Hoeller H. Kurz H. Merk F. Abuzahra 《Skin research and technology》2006,12(4):261-267
BACKGROUND: Three dimensional skin equivalents are widely used in dermatopharmacological and toxicological studies and as autologous transplants in wound healing. In pharmacology, there is tremendous need for monitoring the response of engineered skin equivalents to external treatment. Transplantation of skin equivalents for wound healing requires careful verification of their quality prior to transplantation. Optical coherence tomography (OCT) is a non-contact, non-destructive imaging technique for living tissues offering the potential to fulfill these needs. This work presents an analysis of OCT for high-resolution monitoring of skin equivalents at different stages during the culture process. METHODS: We developed a high-resolution OCT imaging setup based on a commercially available OCT system. A broadband femtosecond laser light source replaces the original superluminescence diode. Tomograms of living skin equivalents were recorded with an axial resolution of 3 mum and correlated with histology and immunofluorescence images. Comparison with standard low-resolution OCT is presented to emphasize the advantages of high-resolution OCT for this application. RESULTS: OCT is particularly able to distinguish between different layers of skin equivalents including stratum corneum, epidermal and dermal layer as well as the basement membrane zone. The high-resolution OCT scans correlate closely with two key benchmarks, histology and immunofluorescence imaging. CONCLUSIONS: This study clearly demonstrates the benefits of high-resolution OCT for identifying living tissue structure and morphology. Compared with the current gold standard histology, OCT offers non-destructive tissue imaging, enabling high-resolution evaluation of living tissue morphology and structure as it evolves. 相似文献