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1.
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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The high incidence and profile of ras gene mutations reported in spontaneous and chemically induced liver tumours of the B6C3F1 mouse provides a potential means of determining in vivo genotoxicity and its relevance to carcinogenicity. We analysed spontaneous and chemically induced [with 4-amino-biphenyl (ABP), 2-acetylaminofluorene (AAF) and diethylnitrosamine (DEN)] hepatocellular tumours of the C57Bl/10J mouse for H-ras, K-ras and N-ras gene mutations to see if mutational analysis of the ras genes could be useful for such a determination in this strain. Regions of DNA spanning codons 12, 13 and 61 of the ras genes were amplified from formalin fixed liver tumour sections using the polymerase chain reaction. Mutations were detected using allele specific oligonucleotide probing and confirmed by sequencing. We have found that there are few ras mutations in either spontaneous or chemically induced liver tumours in the C57Bl/10J mouse. Out of 25 spontaneous tumours two contained an A to T transversion and one contained an A to G transition in base 2 of H-ras codon 61 and two contained a G to A transition in base 2 of K-ras codon 13 (the K-ras mutations were only faintly detectable and may be present in a subpopulation of the tumour cells). In the case of the 18 ABP induced tumours one contained a C to A transversion in base 1 of H-ras codon 61, and one contained an A to T transversion in base 2 of H-ras codon 61 and one contained a G to C transversion in base 1 of K-ras codon 13. One C to A transversion in base 1 of H-ras codon 61 was detected out of eight AAF induced tumours. Of the 25 DEN induced tumours, one contained an A to G transition and one contained an A to C transversion in base 2 of H-ras codon 61. The data indicate that at least in hepatocellular tumours of the C57Bl/10J strain and using chronic dosing regimes the ras genes do not represent markers for in vivo genotoxic activity. 相似文献
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Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
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PL Macken FRACO FRACS CJ Pavlin FRCS R Tuli MD GE Trope PhD FRCS 《Clinical & experimental ophthalmology》1995,23(3):217-220
Background: Spherophakia is an uncommon diagnosis. This is the first case report of spherophakia evaluated by ultrasound biomicroscopy.
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献
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Nancy I Thomas Norman DePaul Brown Linda C Hodges Jay Gandy Louanne Lawson Janet E Lord David K Williams 《AAOHN journal》2006,54(1):24-31
The Central Arkansas Veterans Healthcare System (CAVHS) spends $1 million annually on occupational illnesses and injuries. To address the problem of injuries among hospital employees, a retrospective case-control study was conducted to examine select risk factors for work-related injuries (WRI) among CAVHS employees. Study methods included a review of employee health charts and computer and manual databases from 1997 to 2002 (N = 2,050). The researchers found that WRI increased with age; WRI occurred more often in women than in men; WRI was greater among maintenance and custodial staff compared to direct caregivers, and less among clerical staff; WRI occurred less often in part-time than full-time staff; and WRI increased with increasing body mass index. Developing standards, guidelines, and policies for preplacement screening, preventive measures, training, and education may help to minimize WRI and associated costs. 相似文献
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