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11.
OBJECTIVE: To examine the predictive validity of symptom severity, cognitive and language measures taken at ages 2 and 3 years to outcome at age 7 in a sample of children diagnosed with autism at age 2. METHOD: Twenty-six children diagnosed with autism at age 2 were re-assessed at ages 3 and 7 years. At each age symptom severity, cognitive and language assessments were completed. RESULTS: The pattern of autistic symptom severity varied over time by domain. Across time, children moved across diagnostic boundaries both in terms of clinical diagnosis and in terms of instrument diagnosis on the Autism Diagnostic Interview-Revised (ADI-R). On all measures group variability in scores increased with age. Although non-verbal IQ (NVIQ) for the group as a whole was stable across the 3 assessments, this masked considerable individual instability. Standard assessments at age 2 did not predict outcome at age 7 even within the same domain of functioning. In contrast, standard assessments at age 3 did predict outcome. However, a measure of rate of non-verbal communicative acts taken from an interactive play-based assessment at age 2 was significantly associated with language, communication and social outcomes at age 7. CONCLUSIONS: The trajectory of autism symptoms over time differed in different domains, suggesting that they may be, at least in part, separable. Variability in language, NVIQ and symptom severity increased over time. Caution is required when interpreting the findings from assessments of children with autism at age 2 years. At this age measures of rate of non-verbal communication might be more informative than scores on standard psychometric tests. Predictive validity of assessments at age 3 years was greater.  相似文献   
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Attenuation of acute and chronic pulmonary emboli   总被引:10,自引:0,他引:10  
Wittram C  Maher MM  Halpern EF  Shepard JA 《Radiology》2005,235(3):1050-1054
PURPOSE: To compare retrospectively the attenuation coefficients of acute and chronic pulmonary embolism (PE). MATERIALS AND METHODS: Institutional review board approval was obtained, and informed consent was waived. The study was compliant with requirements of the Health Insurance Portability and Accountability Act. All patients with chronic PE, from July 2001 to January 2004, were identified via a radiology report search system; of the 39 identified, 25 were excluded because the thrombi were too small to measure or were obscured by streak artifacts or because there was no corroborative evidence of chronic PE. Of 27 consecutive patients with acute PE who were also identified, two were excluded because of streak artifacts. The final study group included six women and eight men with chronic PE (mean age, 50 years; range, 26-76 years) and 11 women and 14 men with acute PE (mean age, 61 years; range, 33-83 years) (P = .01 for age). Images were acquired with a four-detector row computed tomographic scanner and 1.25-mm collimation. Two readers made independent attenuation measurements of the largest thrombus in each patient at a workstation. Statistical analysis included calculation of means and standard deviations, the t test, and the Bland-Altman test. RESULTS: Reader 1 found mean attenuation of 90 HU +/- 30 (range, 54-155 HU) for chronic PE and 33 HU +/- 15 (range, 6-63 HU) for acute PE (P < .001). Reader 2 found mean attenuation measurements of 83 HU +/- 32 (range, 32-135 HU) for chronic PE and 33 HU +/- 14 (range, 13-65 HU) for acute PE (P < .001). The mean attenuation for both readers was 33 HU for acute PE (95% confidence interval: 26, 41 HU) and 87 HU for chronic PE (95% confidence interval: 66, 107 HU). The Bland-Altman test demonstrated agreement between readers. CONCLUSION: The mean attenuation measurement in chronic PE is significantly higher than in acute PE.  相似文献   
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AIM: To assess New Zealand's research productivity in the area of ophthalmology and vision science over the decade 1993-2002. METHODS: New Zealand-based researchers involved in ophthalmology or vision science research, including ophthalmologists, optometrists and vision scientists were identified via professional colleges, universities and electronic databases. Peer-reviewed publications by these authors were identified by both searching electronic databases (MEDLINE/Pubmed) and personal communication with individual researchers. RESULTS: Eighty-five New Zealand-based researchers involved in ophthalmology or vision science research published 446 articles in 84 scientific journals during the 10-year period. The cohort consisted of 59 ophthalmologists and 26 other researchers based in a diverse range of ophthalmology, optometry and university departments. Significant collaboration was observed between groups within New Zealand and with international institutions. Comparing ophthalmologists and 'other' researchers, ophthalmologists produced 69% of all ophthalmology and vision science research publications and those classified as 'active ophthalmologist researchers' published an average of 11 (range 5-55) papers each during this decade, compared to eight (range 5-25) for the group 'other active researchers'. This was also reflected in the high productivity rate by ophthalmologists of 277 publications per 1000. Publications were identified in a wide range of journals with the majority in top 20-ranked ophthalmology journals. The trend over the decade highlighted an increase in number of scientific publications, from 43 per annum in 1993, to 68 per annum in 2002. CONCLUSIONS: Despite a relatively small and geographically isolated population, New Zealand ophthalmology and vision science research is highly active and collaborative, with significantly increased research productivity during the period 1993-2002. The present study is the first to document these trends and provides strong evidence to justify continued support for ophthalmology and vision science research in New Zealand.  相似文献   
16.
Castleman's disease, also known as angiofollicular lymphoid hyperplasia, is a lymphoproliferative disorder that is generally benign. The lesions most commonly originate in the lymph nodes of the mediastinum. The second documented case of Castleman's disease of the lacrimal gland is reported in an 84-year-old woman who presented with an 8-year history of a left upper lid mass. This was excised via a lateral orbitotomy, and a diagnosis of Castleman's disease was made histologically. Relevant images of the clinical findings and histology are shown.  相似文献   
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The present study describes a novel meshing procedure that provided successful low-risk papillomavirus propagation and reproducible wart induction in human foreskin xenografts. The initial HPV6 and/or 11 inocula were collected from clinically excised human wart tissues and confirmed to be free of HPV16, 18 and 31 by PCR analysis. Human foreskin grafts were collected from a circumcision clinic, and pre-inoculated with HPV virions by scarification. Meshing was carried out with a Zimmer Skin Grafter Mesher. Grafts were cut to appropriate size (1cm x 1cm or 5mm x 5mm) for cutaneous or subcutaneous grafting to NIH-nu-bg-xid mice under halothane anesthesia. Cutaneous xenografts were dressed with antibiotics and protective band-aids for 3 weeks. In the paralleled experiment using the same viral stock containing both HPV6 and 11, and matched grafts, no visible papillomas were observed in non-meshed cutaneous xenografts (n = 4 up to 6 months). In comparison, six of eight cutaneous xenografts treated with the meshing procedure formed visible papillomas within 4 months. This high frequency of distinct papilloma induction over the surface of meshed xenografts were reproduced in subsequent experiments with viral stocks containing both HPV11 and 6 (8 out of 10 grafts), or with a single-type HPV11 inoculum (80-100%). In contrast, an initial viral stock of single-type HPV6 provided lower frequency and more delayed papilloma induction. Serial passage of HPV6 in the meshed xenograft appeared to improve both the induction frequency and growth rate up to the 3rd generation. Histology, in situ hybridization, and immunohistochemical analysis revealed similarity of xenograft warts to those observed in the clinic. The highly reproducible papilloma induction rate and successful viral stock propagation associated with the meshing procedure provide a novel feature in the HPV xenograft model.  相似文献   
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Small pulmonary nodules: detection at chest CT and outcome   总被引:6,自引:0,他引:6  
PURPOSE: To determine the outcome of pulmonary nodules less than 1 cm in diameter detected at chest computed tomography (CT). MATERIALS AND METHODS: Reports of chest CT performed during 6 months were reviewed to find patients with pulmonary nodules smaller than 1 cm in long axis for which repeat CT was recommended. Records were studied to determine whether follow-up had been performed, the initial nodules had changed in size, or nodules had been resected. RESULTS: A total of 3,446 chest CT examinations were performed, with 334 patients meeting inclusion criteria. Three patients underwent nodule resection and had pathologic examination results positive for cancer; 185 underwent follow-up, of whom 13 had results excluded as indeterminate. In the remaining 172 patients, 88 had incomplete characterization because of follow-up of less than 2 years, which left 84 with nodule characterization at follow-up. When these 84 patients were combined with the three patients with nodule resection, the number yielded was 87 patients. Seventy-seven of 87 had benign nodules because of resolution or 2-year stability, and 10 of 87 had malignant nodules because of growth or positive histologic examination results. Nine of 10 with malignant nodules had a known primary neoplasm. CONCLUSION: CT commonly helped identify small nodules. Increase in size occurred infrequently and almost exclusively in patients with a known malignancy.  相似文献   
20.
Effect of noise reduction filters on chest computed tomographic (CT) images acquired with 50% radiation dose reduction was evaluated. Two sets of images were acquired with multi-detector row CT at standard (220-280 mA) and 50% reduced (110-140 mA) tube current at the level of the carina. After postprocessing with six noise reduction filters, images were compared with baseline standard-dose images for noise, sharpness, and contrast in lungs, mediastinum, and chest wall. Quantitative image noise was measured in descending thoracic aorta. Modulation transfer functions were calculated from CT images of 50-microm wire. Noise reduction filters reduced image noise on low-radiation-dose chest CT images, with some compromise in image sharpness and contrast assessed qualitatively, and slightly altered modulation transfer function at higher spatial frequencies.  相似文献   
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