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Rendering three-dimensional information of a scene from optical measurements is very important for a wide variety of applications. However, computer vision advancements have not yet achieved the accurate three-dimensional reconstruction of objects smaller than 1 cm diameter. This paper describes the development of a novel volumetric method for small objects, using a binocular machine vision system. The achieved precision is high, providing a standard deviation of 0.04 mm. The robustness, of the system, issues from the lab prototype imaging system with the crucial z-axis movement without the need of further calibration and the fully automated volumetric algorithms.  相似文献   
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Objective The objective of the study was to determine the outcomes for primary gastrointestinal melanomas (PGIM). Material and methods The Surveillance, Epidemiology, and End Results database (1973–2004) was queried. Results Overall, 659 cases of PGIM were identified. The annual incidence of PGIM was approximately 0.47 cases per million in 2000. Overall median survival time was 17 months. Tumors were identified in the oral–nasopharynx (32.8%), anal canal (31.4%), rectum (22.2%), esophagus (5.9%), stomach (2.7%), small bowel (2.3%), gallbladder (1.4%), and large bowel (0.9%). Univariate analysis demonstrated age, tumor location, stage, surgery, and lymph node status were significant predictors of improved survival. MST has not been reached for tumors located in the large bowel, while tumors located in the stomach demonstrated the shortest median survival (5 months). Improvement in MST was observed for those patients undergoing surgical resection. The presence of lymph node involvement conferred a poorer prognosis. Multivariate analysis of the cohort identified that location, advanced tumor stage, failure to undertake surgical resection, positive lymph node status, and age were all independent predictors of poorer outcome. Conclusion PGIM occurs most often in the oral–nasopharynx and anal canal. Surgical extirpation is the only identifiable treatment modality that significantly improves survival.  相似文献   
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Increasingly, patients of advanced age are coming for evaluation of periampullary tumors. Although several studies have demonstrated the safety of resecting periampullary tumors in older patients, few long-term survival data have been reported. Between 1983 and 1992 various periampullary masses were resected in 70 patients over age 65 (range 65–87 years). Total pancreatectomy was performed in 11 patients, and 59 patients underwent pancreaticoduodenectomy. The mean duration of hospitalization was 17 ± 15 days. Major complications occurred in 27 patients (39%), and operative mortality rate was 8.5%. Overall median survival was 24 months; and 5-year survival was 25%. Perioperative outcome was compared in patients aged 65 to 74 years and in patients ≥75 years old. The older age group required longer periods in the surgical intensive care unit postoperatively, but the long-term survival was similar in the two age groups. Radical resection with the intent to cure periampullary tumors is safe in selected patients of advanced age, and long-term survival is in the range of expected survival for younger patients with the same tumors.  相似文献   
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Background

Cryotherapy using liquid nitrogen delivered endoscopically has been used for mucosal ablation of esophageal neoplasia. There are no data for the human esophagus on the depth of injury and effects of this technique.

Aim

Prospective study to examine the effect of treatment and depth of injury to the human esophagus of liquid nitrogen spray cryotherapy for subjects with esophageal neoplasia before planned esophagectomy.

Methods

Liquid nitrogen spray cryoablation was performed seven days before scheduled esophagectomy for seven males with esophageal carcinoma. Subjects were assigned to either treatment of four cycles of 10 s each (group 1) or two cycles of 20 s each (group 2) applied to a 2-cm segment of healthy esophagus above the tumor area. Main outcomes measured were: mean depth of injury (mm); surface displaying mucosal ablation, and adverse events.

Results

Mucosal destruction was similar for both groups (group 1, 95 %; group 2, 93 %; p = NS). Deeper injury was observed for group 2; mean depth was 5.4 mm compared with 4.0 mm for group 1. Cryonecrosis reached the submucosa for 60 % (12/20) of subjects in group 1 versus 93 % (14/15) of subjects in group 2 (p = 0.04, two-tailed Fisher’s exact test). No serious adverse events occurred. No perforation was seen in the resected esophagus.

Conclusion

Mucosal ablation with liquid nitrogen spray cryotherapy was highly effective in inducing mucosal necrosis; the doses assessed had similar effects. Ablation reached the submucosa more often with longer spray time despite fewer treatment cycles.  相似文献   
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OBJECTIVE: Analysis of state and national tobacco-associated cancer trends is critical for the identification of high-risk regions of the country that require the attention of the public health community. This study compares Florida race- and gender-specific cancer trends with pooled data obtained from nine Surveillance, Epidemiology, and End Results (SEER-9) registries. METHODS: Age-adjusted, race- and gender-specific cancer incidence trends were evaluated using joinpoint regression analysis. Pooled, age-adjusted incidence rates and standardized incidence rate ratios were computed for each cancer for the years 1999-2003 to compare Florida to SEER-9. RESULTS: Relative to SEER-9 whites and irrespective of gender, lung cancer rates in white Floridians were elevated through the 1990s. However, lung cancer rates have recently declined at a steeper rate among white Floridians than among SEER-9 whites. For years 1999-2003, black Floridians had significantly lower rates of lung, bladder, pancreas, and kidney cancer relative to SEER-9 blacks. The opposite pattern was evident for white Floridians with significantly higher rates of lung and laryngeal cancer relative to SEER-9 whites. CONCLUSION: Progress in the reduction of tobacco-associated cancers among white Floridians lags behind the progress noted in SEER-9 registries suggesting that additional state-directed smoking prevention and smoking cessation measures are needed.  相似文献   
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BACKGROUND: The aims of this study were to measure objectively the extent and severity of motor impairment in children with Asperger's syndrome and to determine whether the motor difficulties experienced by such children differed in any way from those classified as having a Specific Developmental Disorder of Motor Function (SDD-MF). Criteria derived from ICD 10-R were used to identify 11 children with Asperger's syndrome and a matched group of 9 children with a Specific Developmental Disorder of Motor Function. Children in both groups were required to have a verbal IQ of 80 or greater on the WISC IIIR. METHOD: The Autism Diagnostic Interview (Revised; Lord, Rutter, & LeCouteur, 1994) was used to identify features of AS in the first group and to exclude them in the latter. The Movement Assessment Battery for Children (Henderson & Sugden, 1992) provided a standardised test of motor impairment. A Gesture Test based on that by Cermak, Coster, and Drake (1980) was used to assess the child's ability to mime the use of familiar tools and to imitate meaningless sequences of movements. RESULTS: All the children with Asperger's syndrome turned out to meet our criterion for a diagnosis of motor impairment, five of the six most severely motor impaired children in the whole study being from this group. Performance of the Asperger group was also slightly poorer on the Gesture Test. The profile of performance on each test was examined in detail but no evidence of group differences in the pattern of impairment was found. CONCLUSIONS: This study is consistent with others suggesting a high prevalence of clumsiness in Asperger's syndrome. Our findings also attest to the widespread prevalence of motor impairment in developmental disorders and the problems such co-morbidity poses for attempts to posit discrete and functionally coherent impairments underlying distinct syndromes.  相似文献   
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There are several indications that classical Hodgkin lymphoma (cHL) and at least a proportion of cases of Primary Mediastinal B cell Lymphoma (PMBL) are derived from B cells at similar stages of differentiation and share common pathogenic mechanisms. The first indication was the existence of mediastinal grey zone lymphomas as identified in the 4th International Symposium on HL, with clinical, histological and immunohistochemical features intermediate between cHL and PMBL. Second, both tumor types resemble a cell that is developmentally situated in-between the germinal center reaction and a plasma cell. Third, cHL and PMBL were found to have similar gene expression profiles, including the lack of immunoglobulin expression and low levels of B cell receptor signalling molecules, and the secretion of molecules like the chemokine TARC and the prominent expression of IL-13 receptors. Fourth, both entities were found to have common genomic aberrancies, notably in 2p15 and 9p24, the sites of the REL oncogene and the tyrosine kinase gene JAK2, respectively. Further comparison of both lymphoma types may provide further insight in the pathogenic mechanisms and allow the design of diagnostic algorithms to sort out the small number of so-called mediastinal grey zone lymphomas, that appear to be intermediate between PMBL and cHL.  相似文献   
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