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排序方式: 共有663条查询结果,搜索用时 250 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
K J Ottenbacher 《Archives of physical medicine and rehabilitation》1992,73(2):121-125
The incidence of type IV errors was examined in 71 rehabilitation research studies, including a two-way analysis of variance with a statistically significant interaction. The interpretation of the significant interaction was examined to determine whether it qualified as a type IV error. A type IV error was defined as the incorrect interpretation of a correctly rejected null hypothesis. Statistically significant interactions were classified in one of the following categories: (1) correct interpretation, (2) cell mean interpretation, (3) main effect interpretation, or (4) no interpretation. Interpretations classified as cell means or main effects were considered type IV errors. The analysis revealed that 21% of the interactions were correctly interpreted and 63% of the interactions were classified as type IV errors. The remaining 16% of the studies showed a statistically significant interaction but no interpretation. The implications of statistical conclusion validity and type IV errors are discussed, and methods to eliminate or reduce the incidence of type IV errors in rehabilitation research are presented. 相似文献
3.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
4.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
5.
Explored the relationship between vestibular function as measured by duration of postrotary nystagmus and human figure drawing ability in 40 children labeled as learning disabled. Regression analysis revealed that the variable of chronological age shared the most variance with human figure drawing scores. Postrotary nystagmus durations also shared a significant amount of variance with human figure drawing scores, while the variables of IQ and sex were nonsignificant. The results provide additional support for the assertion that some learning-disabled children evidence deficits in vestibular processing ability and that these deficits may affect performance on cognitive-perceptual tasks. 相似文献
6.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
7.
Raji MA Tang RA Heyn PC Kuo YF Owen SV Singh S Ottenbacher KJ 《Journal of the National Medical Association》2005,97(6):808-814
PURPOSE: We conducted a cross-sectional study examining potentially modifiable factors associated with cognitive impairments (mild or severe) in older whites, African Americans and Hispanics attending an outpatient eye clinic. METHODS: In-clinic interviews and physical examinations assessed social, demographic and health information from 100 consecutive Hispanic, African-American and white adults aged > or = 55. Our primary outcome was presence of any cognitive impairment (mild or severe) using the St. Louis University Mental Status Examination (SLUMS) scale. RESULTS: Of the 100 subjects, 65 screened positive for cognitive impairments on the SLUMS cognitive instrument: 46 with mild cognitive impairment and 19 with severe impairment (possible dementia). African-American and Hispanic adults (nonwhites) were significantly more likely to have cognitive impairment compared to white adults (OR 2.80: 95% CI = 1.05-7.44), independent of age, years of education and systolic blood pressure. Subjects with diabetes also had increased odds of cognitive impairments (OR 3.28, 95% CI = 1.21-8.90) even after adjusting for relevant confounders. There was a nonsignificant trend between visual acuity impairment and cognitive impairment (p = 0.059). CONCLUSIONS: Sixty-five percent of adults aged > or = 55 attending the eye clinic screened positive for cognitive impairments, with higher rates among nonwhites and adults living with diabetes. 相似文献
8.
9.
Ottenbacher KJ Msall ME Lyon N Duffy LC Granger CV Braun S 《Developmental medicine and child neurology》1999,41(3):186-194
This study compared performance on the Functional Independence Measure for Children (WeeFIM), the Battelle Developmental Inventory Screening Test (BDIST), and the Vineland Adaptive Behavior Scales (VABS) in children with developmental disabilities. The three instruments were administered to 205 children with identified disabilities. All 205 children were tested using the WeeFIM instrument. The BDIST was administered to 101 children and the VABS to the remaining 104 children. Administration was counterbalanced and randomized across all three instruments. A proportional sampling plan was used to select the 205 children, who ranged in age from 11 to 87 months. A variety of medical diagnoses and levels of severity of motor, cognitive, and communication impairments were systematically included in the sample. Correlations (r) among subscales for all three instruments ranged from 0.42 to 0.92. Correlations for total scores ranged from 0.72 to 0.94. Analyses of potential moderator variables found no significant relation between age and severity of disability (r=0.05) or between socioeconomic status (SES) and severity of disability (r=0.21). Correlations with age were strongest for those subscale scores involving gross and fine motor skills. Correlations with SES and subscale scores ranged from 0.03 to 0.18. The three instruments provide important information regarding childhood performance in motor, self-care, communicative, cognitive, and social skills. The WeeFIM instrument requires less administration time and provides information directly relevant to evaluating functional outcomes for children with disabilities and their families. 相似文献
10.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1