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61.
Results of a study observing autistic children's interactions with nonhandicapped and autistic peers are reported. Six 8- to 12-year-old autistic children played in dyads with younger, normally developing kindergarten children and with nonhandicapped peers matched on chronological age for 10 15-minute sessions spaced over 3 weeks and then with a playmate of the alternate age for another 10 sessions. After intervention, all subjects showed gains in proximity, orientation, and responsiveness when playing with nonhandicapped peers and with autistic classmates. Same-age nonhandicapped playmates initiated more frequently than did younger nonhandicapped playmates and were better able to modify their initiations in ways that increased the likelihood of response from the autistic children.  相似文献   
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There is limited information regarding oral health status and other predictors of oral health‐related quality of life. An association between oral health status and perceived oral health‐related quality of life (OHQOL) might help clinicians motivate patients to prevent oral diseases and improve the outcome of some dental public health programs. This study evaluated the relationship between older persons' OHQOL and their functional dentition, caries, periodontal status, chronic diseases, and some demographic characteristics. A group of 733 low‐income elders (mean age 72.7 ISD=4.71, 55.6% women, 55.1% members of ethnic minority groups in the U.S. and Canada) enrolled in the TEETH clinical trial were interviewed and examined as part of their fifth annual visit for the trial. OHQOL was measured by the Geriatric Oral Health Assessment Index (GOHAI); oral health and occlusal status by clinical exams and the Eichner Index; and demographics via interviews. Elders who completed the four‐year assessment had an average of 21.5 teeth (SD=6.9). with 8.5 occluding pairs (SD=4.6), and 32% with occlusal contacts in all four occluding zones. Stepwise multiple regressions were conducted to predict total GOHAI and its subscores (Physical, Social, and Worry). Functional dentition was a less significant predictor than ethnicity and being foreign‐bom. These variables, together with gender, years since immigrating, number of carious roots, and periodontal status, could predict 32% of the variance in total GOHAI, 24% in Physical, 27% in Social, and 21 % in the Worry subscales. These findings suggest that functional dentition and caries influence older adults' OHQOL, but that ethnicity and immigrant status play a larger role.  相似文献   
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Orthotopic placement of in vitro propagated Dunning R3327 AT-3 tumor cells resulted in a greater percentage of tumor takes and a two-fold shift in the exponential growth curve compared to flank implantation. The orthotopic tumor appeared to disseminate preferentially to regional lymph nodes, rather than to the lungs which is characteristic of flank tumors. The results suggest an important role of stromal-epithelial interactions in the growth of this tumor. © 1995 Wiley-Liss, Inc.  相似文献   
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A range of 18 derivatives of flavone-8-acetic acid (FAA) with substituents on the 2-phenyl group have been prepared and their anti-tumour activity evaluated in vitro against a panel of human and murine tumour cell lines and in vivo against MAC 15A. There was no clear-cut relationship between in vitro and in vivo activity but the activity in each situation was found to be very sensitive to the precise substitution pattern with closely related isomers giving widely different activities. Some of the compounds, notably 10b,cj , and r , were active in vivo and these require further studies in order to evaluate their potential for development.  相似文献   
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Objectives.To test the safety, efficacy, and toxicity of gene therapy using wild-type p53-expressing adenovirus (Ad-CMV-p53) in a nude mouse model with intraperitoneal (ip) 2774 human ovarian cancer cell line that contains a p53 mutation.Study design.An initial study of adenovirus tolerance was determined in nude mice by a single ip injection of increasing doses of Ad-CMV-p53. Nude mice were implanted with an LD100dose of 1 × 107cells. To study the efficacy and specificity of Ad-CMV-p53 treatment, the mice received treatment with different adenovirus constructs. One group received Ad-CMV-p53 and another group received a control adenovirus construct, Ad-CMV-βgal. To study the treatment response to Ad-CMV-p53, the mice were divided into groups and received various treatment schedules of 1 × 108pfu of Ad-CMV-p53.Results.The mice tolerated Ad-CMV-p53 without adverse effects at doses of 1 × 108pfu. The response to Ad-CMV-p53 showed significant survival duration in each dose regimen, with a survival time greater than that of untreated animals (P= 0.0173). However, no statistically significant survival advantage was observed between Ad-CMV-p53- and Ad-CMV-βgal-treated mice.Conclusions.These studies show that at the adenovirus dose and administration regimen used, there is effective but not specific 2774 tumor growth inhibitionin vivo.Efficient introduction of biologically active genes into tumor cells would greatly facilitate cancer therapy. Thus, although promising, these results caution that much effort will be required to realize the potential for clinical application of adenovirus-based ovarian cancer gene therapy.  相似文献   
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