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171.
TD—SCDMA是2005年通信行业特别关注的一个焦点,从TD—SCDMA的研发与产业化进展、技术试验、政府引导等各个方面,可以明显看出国家对TD—SCDMA的关注达到了一个新的高度。2005年也可以说是TD—SCDMA的专项测试年,为了进一步支持和检验TD—SCDMA的产业化进展,TD—SCDMA研发和产业化专项专家组为TD—SCDMA网络技术试验制定了总体方案。  相似文献   
172.
Several previous families with differing clinical and pathologic characteristics have demonstrated linkage to the 17q21-22 region. We have performed a linkage analysis with chromosome 17 markers on three families showing autosomal dominant inheritance of non-Alzheimer dementia and 60 kindreds with late-onset familial Alzheimer's disease (FAD). Family A shows unequivocal evidence of linkage with a maximum lod score of 5.0 for marker D17S934 (theta = 0.001). This family has an unusual syndrome of a schizophrenia-like psychosis beginning in the fifth or sixth decade followed by severe dementia with an average disease duration of 13.8 years. Neuropathology from five autopsies in this family has shown marked neurofibrillary tangle formation (NFT), degeneration of the amygdala, and no amyloid plaques. This confirms the presence of a gene associated with dementia on 17q and extends the related phenotype to include schizophrenia-like symptoms and classic NFT pathology. A second family with early aphasia progressing to dementia and cortical-basal ganglion-like degeneration also has suggestive evidence for linkage to 17q. A third family with very early-onset dementia (mean, 31 years) and nonspecific pathology can be excluded from the 17q region and emphasizes additional genetic heterogeneity in non-Alzheimer hereditary dementia. Finally, we also present evidence against linkage to D17S579 in the set of 60 families with late-onset FAD, providing further evidence that the chromosome 17 gene is unlikely to be involved in the pathogenesis of typical AD.  相似文献   
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174.
OBJECTIVES: To evaluate if caregivers are reliable informants concerning memory deficits in patients with Alzheimer's disease (AD). DESIGN: Responses of caregivers of patients with probable AD and responses of healthy control subjects on a standardized memory questionnaire were compared with objective measures of cognition (Consortium to Establish a Registry for Alzheimer's Disease neuropsychological battery) and with clinical estimates of activities of daily living, depression, and psychopathology (Consortium to Establish a Registry for Alzheimer's Disease [CERAD] clinical assessment battery) using the Self-report Memory Questionnaire. SETTING: A federally funded AD research center. SUBJECTS: The referred sample included 117 patients with probable AD, their informants, and 41 healthy control subjects age-matched to the patients. Patients and control subjects were between the ages of 58 and 85 years, had between 9 and 19 years of education, and were in good health. EXCLUSIONS: Patients who did not meet NINCDS-ADRDA criteria of probable AD. MAIN OUTCOME MEASURE: The optimal number of questionnaire items yielding the best combination of sensitivity and specificity. RESULTS: An abbreviated version of the scale, renamed the Short-Memory Questionnaire, had excellent specificity and sensitivity for identifying dementia. Positive and negative predictive values were 63.5% and near 100%, respectively. The Short-Memory Questionnaire showed good reliability, internal consistency, and external validity. Caregiver appraisals of memory deficits significantly correlated with objective measures of memory and also with generalized cognitive dysfunction. CONCLUSIONS: Caregivers of patients with AD are reliable informants of their relatives' deficits. The Short-Memory Questionnaire is an easily administered, informant-based scale that may be useful in clinical settings or epidemiologic studies to screen out persons with memory difficulties.  相似文献   
175.
The present study was conducted to determine the effects of dietary fatty acids on hepatic LDL receptor (LDLr) protein abundance and mRNA levels. Sixty pigs were randomized into 10 groups and fed corn-soybean meal diets containing three cholesterol levels (0.25%, 0.5%, and 1.0%, w/w) with no added fat, or fats rich (30% of calories) in palmitic acid or linoleic acid. A control group was fed the base diet with no added fat. After 30 days, plasma LDL-cholesterol (LDL-C) levels increased as the dietary cholesterol increased (P < 0.05); however, there was no significant effect of either fatty acid. Dietary fatty acids, however, had distinctly different effects on hepatic LDLr protein (analyzed by ELISA) and mRNA (analyzed by Northern blot) abundance. When pigs consumed diets containing 0.25% cholesterol, linoleic acid increased hepatic LDLr protein 40% whereas palmitic acid reduced it 40% (P < 0.05). These changes in LDLr protein abundance were accompanied by parallel changes in hepatic LDLr mRNA; linoleic acid increased LDLr mRNA 2-fold (P < 0.01), whereas palmitic acid decreased it 60% (P < 0.01). The differential effects of fatty acids on LDLr expression were only observed at 0.25% cholesterol, suggesting that higher intakes of cholesterol have a dominant and repressive effect on regulation of LDLr expression. Cholesterol intake increased hepatic total cholesterol levels (P < 0.01) while dietary fatty acids had no effect on hepatic sterols. In summary, our results indicate that dietary linoleic acid and palmitic acid have markedly different effects on hepatic LDLr protein abundance that are mediated by differential effects on LDLr mRNA and protein levels. Further studies are needed to fully elucidate the molecular mechanisms by which fatty acids regulate LDLr mRNA and protein levels.  相似文献   
176.
OBJECTIVE: To determine the prevalence of vitamin D deficiency in young Nigerian children residing in an area where nutritional rickets is common. Study design: A randomized cluster sample of children aged 6 to 35 months in Jos, Nigeria. RESULTS: Of 218 children evaluated, no child in the study had a 25-hydroxyvitamin D (25-OHD) concentration <10 ng/mL (the generally held definition of vitamin D deficiency). Children spent an average of 8.3 hours per day outside of the home. Twenty children (9.2%) had clinical findings of rickets. Children with clinical signs of rickets were more likely to be not currently breast fed and have significantly lower serum calcium concentrations than those without signs of rickets (9.1 vs 9.4 mg/dL, respectively, P =.01). Yet, 25-OHD levels were not significantly different between those children with clinical signs of rickets and those without such clinical signs. CONCLUSION: Vitamin D deficiency was not found in this population of young children in whom clinical rickets is common. This is consistent with the hypothesis that dietary calcium insufficiency, without preexisting vitamin D deficiency, accounts for the development of clinical rickets in Nigerian children.  相似文献   
177.
The unfavourable tuberculosis situation in the corrective labour facilities affects the main rates of tuberculosis in the region. Presently, the total registered cases of tuberculosis among prisoners are 36.7 times as high as those in the age-matched general population of the Sverdlovsk Region. The rates of relapses, incidence, death due to tuberculosis show 72.0-, 36.1-, and 10.4-fold increases, respectively. Almost every 10 persons from the labour corrective facilities suffer from active tuberculosis. In the past decade, the growth rates of main tuberculosis parameters in the corrective labour facilities were much higher (total tuberculosis morbidity by 2.1 times, relapses by 2.1 times, general morbidity by 1.7 times, and total tuberculosis mortality by 2.8 times) than those in the region's general population. Extrapulmonary tuberculosis was not virtually detected in the labour corrective facilities) due to the lack of special diagnostic methods.  相似文献   
178.
Quantitation of myocardial perfusion is feasible using contrast enhanced magnetic resonance imaging. A method to quantitate myocardial blood flow is provided by the Kety model modified to account for a diffusable tracer such as gadoteridol. In the present study, perfusion parameters of the modified Kety model (partition coefficient and extraction efficiency) were determined for gadoteridol in intact myocardium using a constant flow, isolated, perfused heart model. Perfusion conditions included hearts with normal perfusion, hearts made globally ischemic for 20 min then perfused normally, and hearts whose coronary flow was more than doubled with 9 microM adenosine. T1 relaxation times were rapidly measured at 0.5 T following step increases in perfusate gadoteridol concentration and at steady state. Both the partition coefficient and extraction efficiency were found to be significantly increased in ischemic/reperfused hearts compared to normal. While flow rates in adenosine hearts were too high for accurate extraction efficiency determination using this technique, the partition coefficient was no different between adenosine and normally perfused hearts. The method described in this article allowed the kinetic parameters of the modified Kety model to be determined in intact heart using NMR relaxation time measurements as the basis of the calculation.  相似文献   
179.
OBJECTIVE: Our purpose was to determine the significance of finding an isolated clubfoot on a prenatal sonogram. STUDY DESIGN: All fetuses found to have an isolated congenital clubfoot over a 9-year period were retrospectively identified. Fetuses with associated anomalies were excluded. Review of medical records for obstetric and neonatal outcome and pathologic and cytogenic results were tabulated. RESULTS: Eighty-seven fetuses were identified from our database as having isolated clubfoot on prenatal ultrasonography, with complete follow-up available for 68 fetuses. Sixty of the 68 fetuses were confirmed as having clubfoot after delivery (false-positive rate = 11.8%). The male/female ratio was 2:1. Four fetuses (5.9%) had abnormal karyotypes: 47,XXY, 47,XXX, trisomy 18, and trisomy 21. Nine fetuses had hip or other limb abnormalities noted after birth. Other anomalies not detected until delivery included a unilateral undescended testis, ventriculoseptal defects (n = 2), hypospadias (n = 2), early renal dysplasia, mild posterior urethral valves, and a two-vessel cord. Five of the 68 patients (including those with aneuploidy) had pregnancy terminations. Eleven patients were delivered preterm. CONCLUSION: Karyotypic evaluation is recommended when isolated clubfoot is identified on prenatal sonogram because other subtle associated malformations may not be detected ultrasonographically in the early second trimester.  相似文献   
180.
We studied the results of different durations of application of the Pavlik harness for congenital dislocation or subluxation of the hip. For this, 110 hips in 106 patients were successfully reduced and examined when 6 years old. Dislocation and subluxation cases were divided into two groups: a long-term (4 months for dislocation and 3 months for subluxation) and a short-term (3 months for the former and 2 months for the latter) group. We compared them by roentgenographic analysis. The association between the long- and short-term groups was tested using statistical analyses. There were no significant differences between them, except for one item in subluxation. Therefore, we can say that the duration of application of the Pavlik harness should be reduced to 3 months for dislocation and 2 months for subluxation.  相似文献   
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