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71.
In this study we have analyzed the vascular response induced in the two- stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not been explored in this model, which is the paradigm of multistage carcinogenesis and a model for neoplastic lesions derived from exophytic premalignant lesions (e.g. colon carcinoma, bladder papilloma). We investigated if angiogenesis is involved in the formation of papillomas and in the progression from papilloma to carcinoma. To this end we analyzed the vasculature of normal and hyperplastic skin, focal epidermal hyperplasias that are precursors of papillomas, papillomas at different stages and squamous cell carcinomas. We also analyzed the vascularization of papillomas induced in two strains of mice that differ in their susceptibility to malignant progression. We show here that angiogenesis is turned on in the earliest stages of papilloma formation. In late stages, regardless of state of progression, the predominant response is an increase in the size of blood vessels. Thus, in the SENCAR mouse model, representative of exophytic tumors, the angiogenesis switch is a very early event, probably mechanistically related to the development of the primarily exophytic lesions. Therefore, the density of blood vessels cannot be used as a predictor of malignant progression in this model.   相似文献   
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PURPOSE: To determine the relationship between DNA damage and radiosensitivity at low doses (1-10 Gy) for the initial DNA damage and residual DNA damage remaining after 12-h repair. MATERIALS AND METHODS: Eleven cell lines, normal human lung epithelial L132, HT29 human colon carcinoma, ATs4 human ataxia telangiectasia, normal CHO-K1 hamster, repair-deficient xrs1 and xrs5 mutants, repair-deficient SCID rodent cell line, the human normal fibroblast 1BR.3, human ataxia telangiectasia fibroblast AT1BR and the repair-deficient fibroblasts 180BR.B and 46BR.1 were irradiated with 60Co gamma-rays. Radiosensitivity was measured by clonogenic survival assay. DNA damage was measured by fluorometric analysis of DNA unwinding (FADU). RESULTS: The radiosensitivity in the 11 cell lines ranged from SF2 of 0.02-0.61. By FADU assay, the undamaged DNA at 5-Gy ranged from 56 to 93%. The initial DNA damage and radiosensitivity were highly correlated (r2 = 0.81). After 5-Gy irradiation and 12-h repair, two groups of cell lines emerged. Group 1 restored undamaged DNA to a level ranging from 94 to 98%. Group 2 restored the undamaged DNA to a level ranging from 77 to 82%. No correlation was seen between residual DNA damage remaining after 12-h repair and radiosensitivity. CONCLUSION: It is shown that the initial DNA damage correlates with radiosensitivity at low doses of irradiation. This suggests that the initial DNA damage must be considered as a determinant for radiosensitivity.  相似文献   
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OBJECTIVE: The purpose of this study was to describe the relationship between command hallucinations and violent behavior. METHODS: One hundred and three psychiatric inpatients completed measures of command hallucinations, other psychotic symptoms, violent behavior, and social desirability response biases. RESULTS: Thirty percent of the patients reported having had command hallucinations to harm others during the last year, and 22 percent of the patients reported they complied with such commands. Logistic regression analyses suggested that patients who experienced command hallucinations to harm others were more than twice as likely to be violent, even when the analysis controlled for demographic variables, history of substance abuse, and social desirability response biases. CONCLUSIONS: The results support the clinical utility of asking about command hallucinations when assessing the risk of violence in patients with major mental disorders.  相似文献   
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The purpose of this study was to elicit the participants' perspective of a Therapeutic Life Review intervention program delivered by a home care worker. Following the intervention by the home care worker, 13 of the 14 older women receiving home care services were interviewed to examine their experiences. Qualitative data analysis revealed five themes: (1) Someone was there to listen to my story, (2) It was a special time, (3) A valued interaction with the home care worker developed, (4) Remembering was meaningful and pleasurable, and (5) Integration with one's lived experiences was healing. Three case scenarios illustrate the lives of these older women.  相似文献   
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In highly hypnotizable individuals (highs), postural control is more independent of sensory information than in low hypnotizable subjects (lows). The aim of the study was to find out whether locomotion is also less affected in highs than in lows by visual suppression and changes in the neck proprioceptive input. Eighteen highs and 20 lows were asked to walk straight ahead, blindfolded, in basal conditions (face forward), during real and imagined right/left head rotation and mental computation. Highs detected deviations from the straight trajectory better than lows. Their walking direction was more straight during basal conditions and less influenced than the lows' one by mental computation and real/imagined rotation of the head. The results confirm highs' lower dependence on sensory inputs, although this cannot be definitely attributed to a better internal representation of space or to higher behavioral automaticity.  相似文献   
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Oral squamous cell carcinoma (OSCC) is a lethal disease whose incidence is increasing. Epidemiologic studies demonstrate an association between periodontitis and oral cancer, and periodontal pathogens are implicated in the pathogenesis of numerous disorders, including rheumatoid arthritis, cardiovascular diseases, diabetes and gastrointestinal malignancies. Nevertheless, a causal role for periodontal pathogens in OSCC has not been shown, partly due to the lack of an appropriate animal model. Here, utilizing a newly-established murine model of periodontitis-associated oral tumorigenesis, we report that chronic bacterial infection promotes OSCC, and that augmented signaling along the IL-6-STAT3 axis underlies this effect. Our results indicate that periodontal pathogens P. gingivalis and F. nucleatum stimulate tumorigenesis via direct interaction with oral epithelial cells through Toll-like receptors. Furthermore, oral pathogens stimulate human OSCC proliferation and induce expression of key molecules implicated in tumorigenesis. To the best of our knowledge, these findings represent the first demonstration of a mechanistic role for oral bacteria in chemically induced OSCC tumorigenesis. These results are highly relevant for the design of effective prevention and treatment strategies for OSCC.  相似文献   
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