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Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate the long-term safety and efficacy of intrastromal bevacizumab for treatment of deep corneal neovascularization in...  相似文献   
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Noninvasive localized proton magnetic resonance spectroscopy (MRS) was used for differential diagnosis of a focal brain lesion in a 2.5-year-old girl. The clinical signs were a mild head tilt and neck pain. Magnetic resonance imaging (MRI) revealed a lesion in the right hemisphere of the cerebellum, but its nature remained obscure. In this lesion quantitative determinations of cerebral metabolites by fully relaxed, short-echo-time proton MRS revealed markedly lowered N-acetylaspartate (NAA) and pronounced elevations of choline-containing compounds (Cho) and myo-inositol (Ins), whereas metabolite concentrations in cortical gray matter and white matter were within normal ranges. The metabolite pattern of the lesion indicated loss of vital neuroaxonal tissue (low NAA) and enhanced glial proliferation (high Cho and Ins), which, together with the MRI morphology, suggested a brain tumor. The diagnosis was established by neurosurgical exploration and total extirpation of the tumor. Histology confirmed an astrocytoma (WHO II). After 2 weeks' recovery the child was discharged with no neurological signs.  相似文献   
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We have presented a rare case of primary involvement of the anterior mediastinum by osteogenic sarcoma in which CT was useful in demonstrating calcium within the mass, and in distinguishing the mass from surrounding bony structures. Although rare, extraosseous osteogenic sarcoma should be included in the differential diagnosis of a calcified anterior mediastinal mass.  相似文献   
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Contemporary discourse contains numerous examples of use of the concept of culture by social and behavioral scientists. Simple reification, where the speaker makes culture into a thing capable of action exemplifies one usage in public discourse. Some quantitative social scientists attempt to characterize people’s cultural identities by means of a single categorical variable, which often “lumps” people into categories such as “Hispanic” or “Black” that in fact have numerous culturally bounded subcategories. Approaches that emphasize cultural process are preferable to those who attempt to categorize; more complex measures of acculturation help investigators to make convincing analyses of circumstances in which health disparities occur. Examples in which investigators make appropriate use of cultural characterizations demonstrate their utility in investigating health disparities in Haitian American women, injecting and noninjecting drug users, Hispanic youth, and adult Hispanics at risk of HIV infection. Focus on culture in the study of health disparities can identify entanglements between structural factors such as poverty and lack of education and cultural factors such as beliefs about health. Qualitative methods coupled with quantitative methods have great potential to improve investigators’ grasp of cultural nuance while capturing the distribution of qualitatively derived behaviors.  相似文献   
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Originally described by Rosen in 1983, syringomatous nipple adenoma (SAN) is a tumor of disputed histogenesis, which can be problematic both diagnostically and therapeutically. 1 It is a benign primary tumor of breast epithelium with histology similar to that of the syringoma. In the current case, we describe a 40-year-old female with this lesion occurring within a supernumerary breast. This case represents, to our knowledge, the first such reported case, and represents a significant finding as its presence could lend some confusion as to whether or not this represents a benign primary process of breast or a potentially infiltrative tumor of the skin.  相似文献   
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Proteoglycans have been isolated and analysed from extracts of normal and chronically inflamed human gingiva in order to determine the effects of chronic inflammation on these important soft connective tissue extracellular macromolecules. The uronic acid content of glycosaminoglycans isolated by papain digestion of normal and inflamed gingiva did not differ significantly. Likewise, electrophoretic analysis revealed that the content of hyaluronic acid, heparan sulfate, dermatan sulfate and chondroitin sulfute was similar. The sulfated glycosaminoglycans from both sources eluted from a Sepharose C1-6B column with a Kav of 0.45 (approximate Mr 25,000). However, hyaluronic acid from normal gingiva was predominantly of a large size eluting in the void volume of a Sepharose. CL-6B column, while that isolated from inflamed tissue was mostly a small molecular weight species which elutccl in the included volume of a Sepharose CL-6B column. Using dissociative conditions, intact proteoglycans could be more readily extracted from inflamed tissues (90% of the total tissue uronic acid) than from normal tissues where only 80% of the total tissue uronic acid was extractable. Even though DEAE-Sephacel ion-exchange chromatography revealed no differences in charge between normal and inflamed gingival proteoglycans, Sepharose CL-4B chromatography revealed more molecular size polydispersity in samples from inflamed tissue than from normal tissue. Taken together, these results indicate that while hyaluronic acid is depolymerized in inflamed tissue, no evidence of sulfated glycosaminoglycan degradation was found. Therefore, the most likely cause for disruption to the molecular integrity of the proteoglycans is via proteolytic alteration to the proteoglycan core protein.  相似文献   
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Studies of former prisoners of war (POWs) provide valuable insights into posttraumatic adaptation because they gather information from a large population who survived the traumatic experiences of military captivity. Previous studies of POWs have shown elevated rates of psychiatric symptoms and disorders. This report presents evidence from a longitudinal study of three large, representative, national samples of former POWs. The study finds that depressive symptomatology, as measured by the Center for Epidemiologic Studies Depression Scale, is elevated in World War II POWs from the Pacific and European theaters and in Korean conflict POWs. Decades later, depressive symptomatology is found to be strongly associated with prior treatment in captivity. Differences in depressive symptomatology among the three POW groups can be attributed to captivity-related factors and to buffering factors, such as age at capture and education.  相似文献   
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