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11.
Although cytokeratin expression is said to alter with the state of tumor differentiation, few studies appear to have confirmed this in fresh tissues biopsies from oral squamous cell carcinomas. Previous studies have been limited by the number of antibodies utilized, small sample size, or lack of information regarding tumor differentiation. A panel of 8 antikeratin antibodies (of which five recognised the simple epithelial karatins, 8. 18 and 19) were applied to fresh tissue biopsies from 24 oral cancer and 15 normal oral mucosal biopsies. A standard immunocytochemical technique was followed (Vectastain Abc Method), with keratin expression graded on a 3 point scale. Our analysis indicated that simple epithelial keratins (K8. K.I8, K19) were not confined to the more poorly differentiated tumors. This may be relevant to tumor prognosis.  相似文献   
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A survey was sent to all registered dentists in British Columbia regarding their training and attitudes in removable prosthodontics. A reasonable number of the questionnaires were returned so that general comments can be made about perceived needs and suggestions to improve training and practice.There was a clear feeling among the dentists surveyed that dental school training had not prepared them adequately for the clinical practice of removable prosthodontics. It was suggested that increased emphasis be placed on both didactic and clinical instruction. Increasing the number and quality of faculty was frequently mentioned.There was a perceived need for integrated instruction with other disciplines and increased emphasis on total patient care, including areas such as nutrition and psychology.In general, removable prosthodontics was felt to be an important area of continuing education. Short courses, study groups, and programs at meetings were perceived to be desirable and necessary.Prosthodontic care was felt to be a significant need of the population. Inadequate training in dental school would be a disservice to both the practitioners and their patients. Access to high-quality dental care is an important aspect of the quality of life, and removable prosthodontics is an integral and important part of dental care.  相似文献   
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Bone scans were evaluated in 57 patients referred from the nuclear medicine clinic. Areas of normal and abnormal radiopharmaceutical accumulation in the maxilla and mandible were correlated with a clinical and radiographic dental examination. There was an 80% agreement between the areas of normal and abnormal uptake with the clinical and radiographic findings. This was statistically significant (p less than 0.001). Twenty-one patients had clinical and radiographic dental examinations that were within normal limits and yet had abnormal bone scans. Five of these 21 patients were subsequently seen on an emergency basis for treatment of dental abnormalities. These positive areas on the bone scans may be indicating areas of pathosis not detectable by conventional clinical and radiographic diagnostic techniques.  相似文献   
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Social Psychiatry and Psychiatric Epidemiology - Persecutory delusions are one of the key problems seen in psychotic conditions. The aim of the study was to assess for the first time the levels of...  相似文献   
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Background

Early fetuses heal wounds without the formation of a scar. Many studies have attempted to explain this remarkable phenomenon. However, the exact mechanism remains unknown. Herein, we examine the predominant cell types of the epidermis and dermis—the keratinocyte and fibroblast—during different stages of fetal development to better understand the changes that lead to scarring wound repair versus regeneration.

Materials and methods

Keratinocytes and fibroblasts were harvested and cultured from the dorsal skin of time-dated BALB/c fetuses. Total RNA was isolated and microarray analysis was performed using chips with 42,000 genes. Significance analysis of microarrays was used to select genes with >2-fold expression differences with a false discovery rate <2. Enrichment analysis was performed on significant genes to identify differentially expressed pathways.

Results

By comparing the gene expression profile of keratinocytes from E16 versus E18 fetuses, we identified 24 genes that were downregulated at E16. Analysis of E16 and E18 fibroblasts revealed 522 differentially expressed genes. Enrichment analysis showed the top 20 signaling pathways that were downregulated in E16 keratinocytes and upregulated or downregulated in E16 fibroblasts.

Conclusions

Our data reveal 546 differentially expressed genes in keratinocytes and fibroblasts between the scarless and scarring transition. In addition, a total of 60 signaling pathways have been identified to be either upregulated or downregulated in these cell types. The genes and pathways recognized by our study may prove to be essential targets that may discriminate between fetal wound regeneration and adult wound repair.  相似文献   
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