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Malignant teratoid medulloepithelioma of ciliary body is an extremely rare tumor usually occurring in children younger than 5 years of age and is usually amelanotic. Here, we report a very rare case of pigmented malignant teratoid medulloepithelioma in a 20-year old male patient who presented initially with pain, redness and proptosis of right eyeball. The right eyeball was enucleated. A histopathological diagnosis of orbital teratoma was made and no further treatment was given. Four months later, the patient developed another swelling in the same area. A review of the previous histopathology slides revealed a pigmented malignant teratoid medulloepithelioma. No nerve involvement was seen. MRI did not show any intracranial extension. The mass along with rest of the orbital tissue was removed. No adjuvant chemotherapy or radiotherapy was given due to the lack of intracranial extension. The patient was symptom free at 2-year follow-up and the repeat MRI also showed no evidence of recurrence.  相似文献   
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Background

Interpretation of Clark's nevi has generated debate over the years; although criteria have been proposed for grading morphological features of melanocytes, there is still confusion and variability in the assessment of these lesions.

Methods

This is a retrospective observational study conducted on 100 Clark's nevi and 84 melanomas. A single expert dermatopathologist evaluated all blinded and randomized photomicrographs of both the Clark's nevi and melanomas for the presence of 14 cytologic features. Subsequently, a multivariate model was used to obtain sensitivity and specificity.

Results

Clark's nevi showed a significantly higher frequency of absent‐or‐inconspicuous nucleoli over melanoma, whereas mitotic figures, pleomorphism, notching, multiple nucleoli, peppered moth nuclear pattern, flattened adjacent nuclei, prominent nucleoli and vesicular nucleus with rounded nucleoli were found significantly higher in frequency in melanomas.

Conclusion

Our data suggest that nuclear alterations are of value in the differentiation of atypical nevi from melanoma.  相似文献   
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This review draws comparisons between wheat-dependent exercise-induced anaphylaxis (WDEIA) and other food-dependent exercise-induced anaphylaxis (FDEIAs) and discusses the importance of co-factors in its pathophysiology. FDEIA remains an enigmatic condition since it was first described 30 years ago. The sporadic and unpredictable nature of its reactions has puzzled clinicians and scientists for decades, but recent studies on WDEIA have enlightened us about the pathophysiology of this condition. The identification of defined allergic epitopes such as Tri a 19, α-gliadin, β-gliadin and γ-gliadin in WDEIA enables it to become the perfect model for studying FDEIA, but WDEIA is by no means a unique condition. On a larger scale, FDEIA represents a crucial link between IgE-mediated and anaphylactoid reactions and provides supportive evidence for the concept of ‘summation anaphylaxis’ and the need to overcome the ‘allergen threshold’. Future work should focus on identifying more of the FDEIA epitopes and understanding their distinct molecular properties. The development of a biomarker in order to identify patients susceptible to co-factor influences would be invaluable.  相似文献   
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