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941.
BackgroundDaily step count is the simplest measure of physical activity. However, little is known about how daily step count related to time spent in different intensities of physical activity (PA) and sedentary behavior (SB).MethodsThese cross-sectional data were derived from 450 older Japanese adults (56.7% men; mean age, 74.3 years) who were randomly selected from three communities and responded a survey. Daily step count and time spent in moderate-to-vigorous PA (MVPA), light-intensity PA (LPA), and SB were measured using a validated wearable technology (HJA-350IT). Associations of daily step count with time spent in measured behaviors were examined using linear regression models with isometric log-ratio transformations of time-use composition, adjusting for gender, age, and residential area.ResultsParticipants averaged 5,412 (standard deviation, 2,878) steps/d and accumulated MVPA, LPA, and SB corresponding to 4.0%, 34.8%, and 61.2% of daily waking time, respectively. Daily step count significantly increased with increase in time spent in MVPA relative to other behaviors (ie, LPA and SB) and in the ratio of LPA to SB after allowing for MVPA. After stratification, daily step count was significantly related to the ratio of LPA to SB in those taking <5,000 steps/d, but not in those taking 5,000–7,499 and ≥7,500 steps/d.ConclusionsHigher daily step count can be an indicator of not only larger relative contribution of time spent in MVPA, but also higher ratio between LPA and SB, particularly among those who are the least physically active.Key words: accelerometry, exercise, walking, ambulatory, sedentary lifestyle  相似文献   
942.
The municipality of Ath is characterised by the presence, in its center, of two non-ferrous metal industries whose emissions make local residents concerned for their health. Therefore, authorities of the Walloon Region and the municipality of Ath undertook biomonitoring to assess the impact of those industrial emissions on heavy metal body burden in humans.  相似文献   
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944.

Background

Numerous series have documented short and mid-term successes with cemented, metal-backed modern unicompartmental knee arthroplasty (UKA) for avascular osteonecrosis of the knee (AVN). However, data are lacking regarding long-term implant fixation and patient function. The aim of this study is therefore to evaluate the long-term clinical outcome and implant survivorship of patients who underwent UKA for medial knee osteonecrosis (ON).

Methods

Twenty-nine consecutive UKAs performed by 2 senior surgeons (>50 UKAs a year) in 28 patients (19 women and 9 men with a mean age of 67 years) with medial unicompartmental AVN of the knee between 1989 and 2001 were retrospectively reviewed. AVN was diagnosed using X-ray, magnetic resonance imaging scan, and finally confirmed by postoperative sample analysis. The mean patient body mass index was 27 kg/m2. Etiologies were spontaneous/idiopathic AVN in 19 knees (66%) and secondary AVN in 10 knees (33%). The mean follow-up was 21 years (range 15-26).

Results

At 15 years, survivorship of the components free of revision for any cause was 92% (95% confidence interval 87-97). At latest follow-up, 26 years, survivorship of the components free of revision for any reason was 83% (95% confidence interval 74-95). No survivorship difference was found between the patients suffering from spontaneous or secondary ON of the knee (83% vs 90%, P = .6). At latest follow-up, the mean Knee Society Scoring system Knee was 89 points (range 68-100) and 83 (range 66-96) for Knee Society Scoring system Function.

Conclusion

In the longest series to date, medial UKA for treatment of AVN was associated with high survival rates and stable clinical improvement. UKA is a durable and efficient option to treat patients with unicompartmental ON of the knee.Level of Evidence: IV.  相似文献   
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947.
As tumor protein 53 (p53) isoforms have tumor‐promoting, migration, and inflammatory properties, this study investigated whether p53 isoforms contributed to glioblastoma progression. The expression levels of full‐length TP53α (TAp53α) and six TP53 isoforms were quantitated by RT‐qPCR in 89 glioblastomas and correlated with TP53 mutation status, tumor‐associated macrophage content, and various immune cell markers. Elevated levels of Δ133p53β mRNA characterised glioblastomas with increased CD163‐positive macrophages and wild‐type TP53. In situ‐based analyses found Δ133p53β expression localised to malignant cells in areas with increased hypoxia, and in cells with the monocyte chemoattractant protein C‐C motif chemokine ligand 2 (CCL2) expressed. Tumors with increased Δ133p53β had increased numbers of cells positive for macrophage colony‐stimulating factor 1 receptor (CSF1R) and programmed death ligand 1 (PDL1). In addition, cells expressing a murine ‘mimic’ of Δ133p53 (Δ122p53) were resistant to temozolomide treatment and oxidative stress. Our findings suggest that elevated Δ133p53β is an alternative pathway to TP53 mutation in glioblastoma that aids tumor progression by promoting an immunosuppressive and chemoresistant environment. Adding Δ133p53β to a TP53 signature along with TP53 mutation status will better predict treatment resistance in glioblastoma. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
948.
We report that the rates of nasal cocolonization with methicillin-susceptible Staphylococcus aureus and methicillin-resistant coagulase-negative staphylococci can vary widely between patients admitted to different wards within a single hospital. Such cocolonization can greatly influence the performance of molecular methicillin-resistant S. aureus (MRSA) screening tests depending on the methods used and targets selected.  相似文献   
949.
The aim of the study was to better understand blood-flow changes in large arteries and microvessels during the first 15 minutes of reflow in a P7 rat model of arterial occlusion. Blood-flow changes were monitored by using ultrasound imaging with sequential Doppler recordings in internal carotid arteries (ICAs) and basilar trunk. Relative cerebral blood flow (rCBF) changes were obtained by using laser speckle Doppler monitoring. Tissue perfusion was measured with [14C]-iodoantipyrine autoradiography. Cerebral energy metabolism was evaluated by mitochondrial oxygen consumption. Gradual increase in mean blood-flow velocities illustrated a gradual perfusion during early reflow in both ICAs. On ischemia, the middle cerebral artery (MCA) territory presented a residual perfusion, whereas the caudal territory remained normally perfused. On reflow, speckle images showed a caudorostral propagation of reperfusion through anastomotic connections, and a reduced perfusion in the MCA territory. Autoradiography highlighted the caudorostral gradient, and persistent perfusion in ventral and medial regions. These blood-flow changes were accompanied by mitochondrial respiration impairment in the ipsilateral cortex. Collectively, these data indicate the presence of a primary collateral pathway through the circle of Willis, providing an immediate diversion of blood flow toward ischemic regions, and secondary efficient cortical anastomoses in the immature rat brain.  相似文献   
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