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41.
OBJECTIVES: To examine whether treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) in patients with Alzheimer's disease (AD) results in better cognitive function. DESIGN: Randomized double‐blind placebo‐controlled trial. Participants were randomized to therapeutic CPAP for 6 weeks or placebo CPAP for 3 weeks followed by therapeutic CPAP for 3 weeks. SETTING: General clinical research center. PARTICIPANTS: Fifty‐two men and women with mild to moderate AD and OSA. INTERVENTION: CPAP. MEASUREMENTS: A complete neuropsychological test battery was administered before treatment and at 3 and at 6 weeks. RESULTS: A comparison of subjects randomized to 3 weeks of therapeutic versus placebo CPAP suggested no significant improvements in cognition. A comparison of pre‐ and posttreatment neuropsychological test scores after 3 weeks of therapeutic CPAP in both groups showed a significant improvement in cognition. The study was underpowered to make definitive statements about improvements within specific cognitive constructs, although exploratory post hoc examination of change scores for individual tests suggested improvements in episodic verbal learning and memory and some aspects of executive functioning such as cognitive flexibility and mental processing speed. CONCLUSION: OSA may aggravate cognitive dysfunction in dementia and thus may be a reversible cause of cognitive loss in patients with AD. OSA treatment seems to improve some cognitive functioning. Clinicians who care for patients with AD should consider implementing CPAP treatment when OSA is present.  相似文献   
42.
43.

Purpose  

This phase II study was designed in order to evaluate efficacy and safety of the combination of vinorelbine (VNB), fluorouracil (FU) and leucovorin (LV) in patients with metastatic breast carcinoma (MBC) previously treated with anthracyclines and taxanes.  相似文献   
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HIV-1 viral load determination is a crucial step for monitoring the efficacy of highly active antiretroviral therapy (HAART) and predicts disease progression. Real-time PCR based assays are available for monitoring the viral load. They differ in sensitivity, genomic target region and dynamic range. In this study, the performance of the Roche Cobas Taqman HIV-1 v2.0 was evaluated on plasma samples from HIV-1 positive patients in parallel with the Abbott RealTime HIV-1 assay in a routine diagnostic setting. Overall, there was a good agreement between the two assays. However, some samples detected by the Abbott RealTime HIV-1 assay but below the limit of quantitation of the assay were found negative result when tested with the Roche Cobas Taqman HIV-1 v2.0. It is conceivable that signal anomalies or background noise may affect the lower-end precision of the Abbott RealTime HIV-1 assay. Based on these results, it is concluded that it is not recommended to switch platform during longitudinal viral load monitoring of HIV-1 positive patients.  相似文献   
46.
Sensor technology for smart homes   总被引:2,自引:0,他引:2  
A smart home is a residence equipped with technology that observes the residents and provides proactive services. Most recently, it has been introduced as a potential solution to support independent living of people with disabilities and older adults, as well as to relieve the workload from family caregivers and health providers. One of the key supporting features of a smart home is its ability to monitor the activities of daily living and safety of residents, and in detecting changes in their daily routines. With the availability of inexpensive low-power sensors, radios, and embedded processors, current smart homes are typically equipped with a large amount of networked sensors which collaboratively process and make deductions from the acquired data on the state of the home as well as the activities and behaviors of its residents. This article reviews sensor technology used in smart homes with a focus on direct environment sensing and infrastructure mediated sensing. The article also points out the strengths and limitations of different sensor technologies, as well as discusses challenges and opportunities from clinical, technical, and ethical perspectives. It is recommended that sensor technologies for smart homes address actual needs of all stake holders including end users, their family members and caregivers, and their doctors and therapists. More evidence on the appropriateness, usefulness, and cost benefits analysis of sensor technologies for smart homes is necessary before these sensors should be widely deployed into real-world residential settings and successfully integrated into everyday life and health care services.  相似文献   
47.
Obliteration of the small airways is a largely unresolved challenge in pulmonary medicine. It represents either the irreversible cause of functional impairment or a morphologic disorder of limited importance in a multitude of diseases. Bronchiolitis obliterans is a key complication of lung transplantation. No predictive markers for the onset of obliterative remodeling are currently available. To further elucidate the molecular mechanisms of airway remodeling, compartment-specific expression patterns were analyzed in patients. For this purpose, remodeled and nonremodeled bronchioli were isolated from transplanted and nontransplanted lung explants using laser-assisted microdissection (n = 24). mRNA expression of 45 fibrosis-associated genes was measured using quantitative real-time RT-PCR. For 20 genes, protein expression was also analyzed by immunohistochemistry. Infiltrating cells were characterized at conventional histology and immunohistochemistry. Obliterative remodeling of the small airways in transplanted and nontransplanted lungs shared similar grades of chronic inflammation and pivotal fibrotic pathways such as transforming growth factor β signaling and increased collagen expression. Bone morphogenetic protein and thrombospondin signaling, and also matrix metalloproteinases and tissue inhibitor of metalloproteinases, were primarily up-regulated in obliterative airway remodeling in nontransplanted lungs. In transplanted lungs, clinical remodeled bone morphogenetic protein but nonremodeled bronchioli were characterized by a concordant up-regulation of matrix metalloproteinase-9, RANTES, and tissue inhibitor of metalloproteinase-1. These distinct expression patterns warrant further investigation as potential markers of impending airway remodeling, especially for prospective longitudinal molecular profiling.  相似文献   
48.
Single neurons in the primary auditory cortex of the cat show faster adaptation time constants to short- than long-term stimulus history. This ability to encode the complex past auditory stimulation in multiple time scales would enable the auditory system to generate expectations of the incoming stimuli. Here, we tested whether large neural populations exhibit this ability as well, by recording human auditory evoked potentials (AEP) to pure tones in a sequence embedding short- and long-term aspects of stimulus history. Our results yielded dynamic amplitude modulations of the P2 AEP to stimulus repetition spanning from milliseconds to tens of seconds concurrently, as well as amplitude modulations of the mismatch negativity AEP to regularity violations. A simple linear model of expectancy accounting for both short- and long-term stimulus history described our results, paralleling the behavior of neurons in the primary auditory cortex.  相似文献   
49.
Loss-of-function mutations in the genes associated with primary microcephaly (MCPH) reduce human brain size by about two-thirds, without producing gross abnormalities in brain organization or physiology and leaving other organs largely unaffected [Woods CG, et al. (2005) Am J Hum Genet 76:717–728]. There is also evidence suggesting that MCPH genes have evolved rapidly in primates and humans and have been subjected to selection in recent human evolution [Vallender EJ, et al. (2008) Trends Neurosci 31:637–644]. Here, we show that common variants of MCPH genes account for some of the common variation in brain structure in humans, independently of disease status. We investigated the correlations of SNPs from four MCPH genes with brain morphometry phenotypes obtained with MRI. We found significant, sex-specific associations between common, nonexonic, SNPs of the genes CDK5RAP2, MCPH1, and ASPM, with brain volume or cortical surface area in an ethnically homogenous Norwegian discovery sample (n = 287), including patients with mental illness. The most strongly associated SNP findings were replicated in an independent North American sample (n = 656), which included patients with dementia. These results are consistent with the view that common variation in brain structure is associated with genetic variants located in nonexonic, presumably regulatory, regions.  相似文献   
50.

Aim  

The aim of the study was to evaluate whether socio-economic inequalities in the practice of physical activity existed among children and adolescents, using different indicators of socio-economic status (SES).  相似文献   
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