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Background

The hypothesis tested in this study was whether patients with stage III metastatic melanoma confined to their sentinel lymph nodes (SLNs) had a more favorable prognosis than patients who had SLN and non-SLN (NSLN) metastases.

Methods

Patients were identified who were clinically negative in their regional basins but with lymphatic mapping were found to have positive SLNs (331 patients). All patients subsequently underwent a complete lymph node dissection of the lymphatic basin involved, and the total number of metastatic SLNs and NSLNs were documented.

Results

As the regional metastatic disease involves NSLNs, disease-free survival (DFS) and overall survival (OS) decreases. For patients with a total of 2 nodes positive, those with disease confined to the SLNs had a significant better prognosis (DFS and OS: P < .00001) than those in whom 1 SLN and 1 non-SLN was involved. This difference was apparent for those patients with N2 and N3 disease (2 or more nodes positive in their regional basin). A multivariate regression analysis that included Breslow thickness, ulceration, number of positive nodes, and NSLN positivity showed that NSLN positivity (P = .0019) was the most powerful predictor of DFS and OS.

Conclusions

When metastatic melanoma overwhelms the SLN and involves NSLNs, the biologic behavior changes to portend a worse survival, regardless of the total node count positive. These data make the argument that the current N staging system should be changed to incorporate SLN vs NSLN involvement.  相似文献   
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During the period 1964–73, 286 patients were treated for mandibular fractures. 229 patients (80%) attended the follow-up examination. The length of observation was from 1 to 9 years. The treatment and the follow-up evaluations in the 229 patients are described. Early fracture treatment has been the objective, also in patients who have undergone severe cerebral traumas. Antibiotic prophylaxis was implemented in cases of compound fractures. Preservation of teeth and tooth buds in the line of fracture was attempted. Clinical infection occurred in 0.4% of the patients. At the follow-up examination 1 patient presented with a fracture displacement outside the condylar process. Neither malocclusion nor pseudarthrosis following fracture or after treatment were seen. Permanent sensory disturbances in the innervation area of the mental nerve following fracture occurred in 8%. Radiological examination of the teeth in the line of fracture revealed unnoticed apical bone lesions in 17% of 118 patients. In a further 23% there was a negative response to the vitality test. Follow-up control of mandibular fractures is advised at 12 to 18 months after treatment.  相似文献   
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Inhibitory control allows individuals to suppress prepotent responses and resist irrelevant stimuli, and is thought to be a core deficit in Attention-deficit/hyperactivity disorder (ADHD). Whereas numerous studies have investigated neural mechanisms underlying inhibitory control deficits in children with ADHD, less is known about underlying mechanisms in young adults with ADHD. This study explores the neural correlates of inhibitory control in college students with ADHD—a population that, despite comparatively high educational attainment, still shows marked functional impairments in academic, social, and occupational functioning. Participants were 54 college students with ADHD and 29 typically developing peers. Specifically the fronto-centrally located N2 and the centro-parietal P3 event-related potential (ERP) components were hypothesized to show decreased amplitudes for the ADHD group due to their known association with inhibitory control. Dense array electroencephalography (EEG) data was collected during a Go/nogo task. Results show lower accuracy rates for the ADHD group and significant reductions in P3 amplitude as well as a trend for reduced N2 amplitude in nogo trials where subjects successfully inhibited a response. Notably, nogo N2 and P3 amplitudes correlated with the number of ADHD symptoms: namely, smaller amplitudes were associated with more symptoms. We conclude that when compared to their typically developing peers, relatively high functioning adults with ADHD still show a deviant neural signature. These results contribute to the growing literature of adult ADHD and increase our understanding of the neural correlates of inhibitory control associated with ADHD.  相似文献   
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JL, a 25-year-old physiotherapist, became densely amnesic following herpes simplex viral encephalitis (HSVE), causing bilateral damage to medial and ventral areas of her frontal and temporal lobes and their associated circuitry. Three years post-onset, her WAIS-R full scale IQ (Verbal 74, Performance 102) showed an estimated loss of ± 50 points. She displayed severe global amnesia and markedly impaired social cognition. However, her immediate memory, perceptual priming, and cognitive problem-solving abilities were relatively spared. Her retention of professional skills was assessed using simulated physiotherapy scenarios. JL was able to demonstrate some procedural skills spontaneously, but was unable to apply them precisely and flexibly to individual patient needs. She showed no memory of theoretical or propositional physiotherapy knowledge, and could neither plan treatment nor reason clinically. Her performance was well below that of four other physiotherapists who had also not practised for 4 years. Thus, despite the relative sparing of her implicit memory, JL's performance lacked the co-ordinated operation of declarative and implicit long-term memory and the links to working memory that are necessary for the flexible performance of complex professional procedures.  相似文献   
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