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161.
We present a case of intrapulmonary metastasis developing 18 years after complete resection of thymoma. An 8 mm nodule in the lower lobe of the left lung was noted on chest X-ray in a 76-year-old woman who had undergone complete resection of Masaoka’s stage II thymoma 18 years earlier. Since the nodule grew to 17 mm during a 2-year follow-up, wedge resection was performed. The lesion was histologically diagnosed as an intrapulmonary metastasis from thymoma. Extremely late recurrence after complete resection of thymoma is discussed.  相似文献   
162.
A 72-year-old man presented with a short duration of symptoms relating to a right fronto-parietal glioblastoma and a family history of children with brain tumours. Analysis of the patient's family tree revealed that out of seven children, he had a living son with anaplastic astrocytoma, a daughter who had died with a glioblastoma, and a son who had died with a histologically undiagnosed intrinsic brain tumour. One niece was also thought to have died from a brain tumour. All of the other affected family members had onset in their third or fourth decades. Tissue was only available from two of the affected individuals, precluding familial genetic analysis at this stage. There is no clinical evidence to support a diagnosis of a multiple cancer or neurocutaneous syndrome in this family. In view of what is known about the genetics of familial glioma, it is interesting to note the clinical evidence of both 'primary' glioblastoma and anaplastic astrocytoma in the same kindred.  相似文献   
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OBJECTIVE: The uncinate process (UP) is an important anatomic landmark in frontal recess surgery. Its superior attachment shows great anatomic variability. The agger nasi (AN) cell is another important structure that affects frontal recess anatomy and there is a close neighborhood between them. The aim of this study was to investigate the relationship between superior attachment type of UP and the presence of AN cell. STUDY DESIGN: A retrospective anatomical study. METHOD: Computed tomography scans were evaluated of 486 sides of 243 patients who had had paranasal sinus. In 125 (26%) sides, the superior attachment of the UP could not be identified. In the remaining 361 (74%) sides, the prevalence of superior attachment of UP types and the presence of AN cell in each side were recorded. The results were evaluated with chi2 test. RESULTS: The AN cell was found in 290 (80.3%) of 361 sides. The prevalence of AN cell according to superior attachment of UP types were 79.6% for type 1/2, 90.1% for type 3, 71.4% for type 4, 86.5% for type 5, and 83.3% for type 6. The presence of AN cell according to superior attachment types of UP was not statistically significant (chi2= 3.54, P = 0.315). CONCLUSIONS: The AN cell was found to be present in 80.3% of the cases. However, the relationship between the presence of the AN cell and the superior attachment types of UP was not statistically significant.  相似文献   
165.
The authors discuss techniques for Monte Carlo (MC) cohort simulations that reduce the number of simulation replications required to achieve a given degree of precision for various output measures. Known as variance reduction techniques, they are often used in industrial engineering and operations research models, but they are seldom used in medical models. However, most MC cohort simulations are well suited to the implementation of these techniques. The authors discuss the cost of implementation versus the benefit of reduced replications.  相似文献   
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OBJECTIVE: To study the effect of high-frequency (100 Hz) repetitive conditioning electrical stimulation (CES, 10 min) on human somatosensory evoked potentials (SEPs) to evaluate if short-term cortical plasticity could be induced. METHODS: Painful electrical stimulations were applied to thumb (D1) and little finger (D5) fingertips, respectively. The 124-channel EEG was recorded from 10 healthy male volunteers. Peak stages around 34, 45, 212, 331 ms were analyzed with focal maximum amplitude (FA) and area magnitude (AM) of scalp field potential, topography, and equivalent current dipole source localisation, comparing before and after two-level CES (high- vs. low-level) applied to the He-Gu acupoint. RESULTS: After a high-level CES, the positive FA and AM of the current efflux showed a significant increase at the early phase 34 ms, and significantly decreased at 45 ms in D1 SEPs. The negative FA and AM of the current influx were significantly increased at late phase 350 ms of the D5 SEPs. Only 36 ms, the z-axis position of dipole was significantly changed from (x: -15.9 mm, y: 29.6 mm, z: 43.9 mm) to (x: -12.9 mm, y: 29.4mm, z: 51.5mm) for the D5 SEPs. CONCLUSIONS: The high-level CES significantly attenuated the subsequent cortical activation (45 ms peak for D1 stimulation). Both low- and high-level CES significantly enhanced the late activities (226, 350 ms) in D5 stimulation. This may be explained by pain sensation change at the level of subcortical cingulate cortex induced by the site-dependent post-effect of CES. SIGNIFICANCE: This study showed cortical plasticity induced by conditioning somatosensory stimulation.  相似文献   
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