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排序方式: 共有662条查询结果,搜索用时 15 毫秒
121.
Jeroen SL de Munter Irene GM van Valkengoed Charles Agyemang Anton E Kunst Karien Stronks 《The international journal of behavioral nutrition and physical activity》2010,7(1):1-8
Purpose
The level of recommended physical activity (PA) is met less frequently by people from some ethnic minorities than others. We explored whether these differences in recommended PA between ethnic minority groups and the general population varied by domain and type of culturally-specific activity.Methods
Participants were sampled from the population based SUNSET study and were from ethnic Dutch (n = 567), Hindustani-Surinamese (n = 370) and African-Surinamese (n = 689) descent. The validated SQUASH-questionnaire measured PA for the following domains: commuting, occupation, household, leisure time. Culturally-specific activities were added as extra question within the leisure time domain. The effect of each domain on ethnic differences in recommended PA prevalence was examined by odds-ratio (OR) analysis through recalculating recommended PA, while, in turn, excluding the contribution of each domain.Results
In the ethnic Dutch population, more vigorous PA in commuting and leisure time was reported compared to the Surinamese groups. The Hindustani-Surinamese and African-Surinamese reported more walking as commuting activity, while the Dutch group reported cycling more frequently. Ethnic differences in recommended PA became smaller in both Surinamese groups compared with the Dutch after removing commuting activity, for example, in Hindustani-Surinamese men (OR = 0.92, 95%CI: 0.62-1.37 vs. OR = 1.33, 0.89-2.00) and women (OR = 1.61, 1.12-2.32 vs. OR = 2.03, 1.41-2.92). Removing occupational activity resulted in larger ethnic differences in both groups compared with the Dutch. Smaller effects were found for yoga and dancing, leisure time and household activities.Conclusion
This study shows that differences in PA between ethnic minority groups and the general population vary according to the activity domain. The results indicate that including all relevant domains and activities is essential for assessment of ethnic differences in recommended PA. 相似文献122.
Kate Roberts Vanessa Culleton Zarnie Lwin Kenneth O'Byrne Brett GM Hughes 《Asia-Pacific Journal of Clinical Oncology》2017,13(4):277-288
Immune checkpoint inhibitors have recently emerged as an exciting new treatment paradigm across a broad spectrum of malignancies. This new class of agents also challenges oncologists with a unique set of immune‐based toxicities. Early recognition and precise management of these toxicities can result in better outcomes, with minimization of toxicity and harm to the patient. This article provides a comprehensive review of immune‐based toxicities caused by immune checkpoint inhibitors, including recommendations for their investigation and guidelines for specific management. 相似文献
123.
R. A. Sinico N. Mezzina B. Trezzi GM. Ghiggeri A. Radice 《Clinical and experimental immunology》2016,183(2):157-165
Membranous nephropathy (MN), the leading cause of nephrotic syndrome in adults, is characterized by the deposition of subepithelial immune deposits that consist mainly of immunoglobulin (Ig)G and complement. Most of the cases are primary or idiopathic (iMN), while only approximately 25% of the cases are secondary to some known disease such as systemic lupus erythematosus, hepatitis B, drugs and malignancies. Most of our knowledge on the pathogenesis of iMN has relied upon old experimental models (i.e. Heymann nephritis) that have shown that immune deposits are formed in situ by the reaction of autoantibodies against the respective podocyte antigen. Recent findings indicate that podocyte proteins also act as an autoantigen in human iMN. The M‐type phospholipase A2 receptor (PLA2R) has been identified as the main target antigen, as it can be found in approximately 70% of iMN patients but only rarely in other glomerulonephritides. Podocytes damage in the experimental model of Heymann nephritis is complement‐mediated. In humans, the presence of complement within the subepithelial deposits is well established, but IgG4, which does not activate complement by classical or alternative pathways, represents the predominant subclass of IgG anti‐PLA2R. Some evidence suggests that IgG4 anti‐PLA2R autoantibodies can bind mannan‐binding lectin (MBL) and activate the lectin complement pathway. A genetic background for iMN has been demonstrated by genome‐wide association studies that have shown highly significant associations of the PLA2R1 and the human leucocyte antigen (HLA)‐DQA1 loci with iMN. In addition to their diagnostic value, anti‐PLA2R antibodies may be useful to monitor disease activity and predict response to treatment. 相似文献
124.
Background: The use of ozone therapy in the treatment of dental caries is equivocal. The aim of this study was to use an in vitro model to determine the effects of prior ozone application to dentine on biofilm formation and to measure any associated reduction in bacteria viability. Methods: Twenty dentine discs were bonded to the bases of 5 mL polycarbonate screw top vials. Ten dentine discs were infused with ozone for 40 seconds, 10 samples remained untreated as a control. The vials were filled with nutrient medium, sterilized and placed into the outflow from a continuous chemostat culture of Streptococcus mutans and Lactobacillus acidophilus for four weeks. At the conclusion of the experiment bacterial growth was monitored by taking optical density readings of the growth medium in each vial and the outer surface of the dentine specimens were examined by scanning electron microscopy as shown by SEM analysis. Results: Ozone infusion prevented biofilm formation on all the treated samples while there was substantial biofilm present on the control specimens. While the average optical density of the control specimens was almost twice that of the ozone infused dentine (0.710 for the control with a SD of 0.288 and 0.446 for the ozonated samples with a SD of 0.371), the results were not significant (p > 0.05). Conclusions: This preliminary study has shown that the infusion of ozone into non‐carious dentine prevented biofilm formation in vitro from S. mutans and L. acidophilus over a four‐week period. The possibility exists that ozone treatment may alter the surface wettability of dentine through reaction with organic constituents. 相似文献
125.
126.
PK Tran A Haworth F Foroudi A Paneghel AG Herschtal KH Tai SG Williams S Soteriou M Laferlita GM Duchesne 《Journal of Medical Imaging and Radiation Oncology》2009,53(6):574-580
The aim of this study is to prospectively evaluate and model surrogate explanatory variables (SEVs) of target coverage and rectal dose pertaining to soft tissue anatomy visualised on cone beam computed tomography (CBCT) for incorporation into post‐prostatectomy treatment coverage verification protocols. Twenty post‐prostatectomy patients treated with conformal prostate bed radiotherapy (64–74 Gy) underwent CBCT daily at fractions 1 to 5, and then weekly. Treatment coverage was defined on each CBCT using ‘PTV95’, percentage of the CBCT PTV covered by original treatment fields, and ‘RECTD50’, dose delivered to 50% of CBCT rectal volume by original treatment fields. Three candidate SEVs for treatment coverage were defined for each scan: anterior rectal wall movement, change in bladder length and bladder base movement. Both anterior rectal wall movement and increase in bladder length predicted for the decreased PTV95 (P < 0.001 for each). Anterior movement of the anterior rectal wall predicted for increased RECTD50 (P < 0.001). Predictive models for the PTV95 and RECTD50 that accept the significant SEVs as inputs were developed. We developed simple CBCT‐acquired soft tissue anatomic surrogate measures that signal changes in target coverage and rectal dose during post‐prostatectomy radiotherapy. Conventional bony anatomy patient position verification protocols were inadequate in accounting for soft tissue target and organ variation seen with CBCT. 相似文献
127.
SC Gandevia GM Allen JE Butler RB Gorman DK McKenzie 《Clinical and experimental pharmacology & physiology》1998,25(10):757-763
1. Given the importance of the ventilatory ‘pump’ muscles, it would not be surprising if they were endowed with both sensory and motor specializations. The present review focuses on some unexpected properties of the respiratory muscle system in human subjects. 2. Although changes in blood gas tension were long held not to influence sensation directly, studies in subjects who are completely paralysed show that increases in arterial CO2 levels elicit strong sensations of respiratory discomfort. 3. Stretch reflexes in human limb muscles contain a monosynaptic spinal excitation and a long-latency excitation. However, inspiratory muscles show an initial inhibition when tested with brief airway occlusions during inspiration. This inhibition does not depend critically on input from pulmonary or upper airway receptors. 4. Human inspiratory muscles (including the diaphragm) have been considered to fatigue during inspiratory resistive loading. However, recent studies using phrenic nerve stimulation to test the force produced by the diaphragm show that carbon dioxide retention (hypoventilation) and voluntary cessation of loading occur before the muscles become overtly fatigued. 相似文献
128.
Walter JB; Brander C; Mammen M; Garboczi DN; Kalams SA; Whitesides GM; Walker BD; Eisen HN 《International immunology》1997,9(3):451-459
HLA-A2 heavy chain and beta 2-microglobulin were expressed in Escherichia
coli, and refolded in the presence of peptides derived from HIV-1 RT and
gag proteins. When recombinant HLA-A2 molecules were attached to cells
lacking HLA-A2, the cells became susceptible to lysis by HLA-A2-restricted
cytotoxic T lymphocyte (CTL) clones specific for peptides derived from RT
and gag proteins. Limiting dilution analyses of peripheral blood
mononuclear cells from HIV-1-infected individuals showed that the
recombinant HLA-A2 peptide complexes covalently immobilized on microspheres
stimulated the development of HLA-A2 peptide-specific CTL. Preformed
HLA-peptide complexes may provide an alternative to immunization procedures
that depend upon intracellular processing of antigen to elicit T cell
responses.
相似文献
129.
L Kovács GM Davis D Faucher A Papageorgiou 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(7):792-798
In order to assess the efficacy of a combination of systemic and nebulized corticosteroids in reducing the incidence and severity of chronic lung disease (CLD) in very low birthweight (VLBW) infants, 60 ventilator-dependent infants ≤ 1500g were randomly assigned to receive either steroids or placebo as of 7d. The steroid group ( n = 30, GA = 25:8 ± 1:6 weeks, BW = 731 ± 147 g) received systemic dexamethasone for 3 d, followed by nebulized budesonide for 18 d. Control infants ( n = 30, GA = 25:9 ± 1.8 weeks, BW = 796 ± 199 g) received systemic and inhaled saline. Steroid-treated infants required less ventilatory support between 9 and 17 d ( p < 0:01), and had greater lung compliance at 10 d ( p = 0:01), but not subsequently. CLD incidence at 36 weeks was 45.5% vs 56.0% in controls, and fewer steroid-treated infants required dexamethasone rescue (23.3% vs 56.7%, p = 0:017). Survival to discharge was similar (73.3% vs 83.3%), as were the durations of mechanical ventilation, supplemental oxygen use, and hospitalization. Tracheal effluent elastase/albumin ratios and serum cortisol values did not differ between groups, and no adverse effects were noted. We conclude that early dexamethasone administration was associated with improved pulmonary function, which was not sustained with nebulized budesonide. However, the steroid regimen studied reduced the need for dexamethasone rescue in infants with CLD. 相似文献
130.