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21.
长期以来的研究表明先天免疫和后天免疫在宿主抵御外来微生物入侵的过程中起着至关重要的作用,而在这过程中也会同时造成宿主自身的组织或器官的损害。骨骼系统就是其中之一,在一些诸如类风湿性关节炎、牙周炎等疾病中,免疫系统的反应不仅起到去除外来致病菌的作用,还会同时造成骨骼系统的破坏。长期以来大部分的研究都致力于了解免疫系统对骨组织破坏的机制,而近些年来有研究开始探究骨反作用于免疫系统,由此衍生出了一个全新的研究领域——骨免疫。文章从骨免疫的机制、免疫与骨吸收作用通路以及在口腔相关疾病的作用机制等方面总结了近些年来相关的研究进展。  相似文献   
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BackgroundMany activity trackers have been developed, but steps can still be inconsistent from one monitor to another.Research questionWhat are the differences and associations between the steps of 13 selected consumer-based and research-grade wearable devices during 1 standardized day in a metabolic chamber and 15-day free-living trials?MethodsIn total, 19 healthy adults between 21 and 50 years-old participated in this study. Participants were equipped with 12 accelerometer-based active trackers and one pedometer (Yamasa) in order to monitor the number of steps per day. The devices were worn on the waist (ActiGraph, Omron, Actimarker, Lifedorder, Withings, and Yamasa) or non-dominant wrist (Fitbit, Garmin, Misfit, EPSON, and Jawbone), or placed in a pocket (Omron CaloriScan, and TANITA). Participants performed structured activities over a 24 h period in a chamber (Standardized day), and steps were monitored in the same participants in free-living trials for 15 successive days using the same monitors (free-living days).ResultsWhen the 13 monitors were ranked by their steps, waist-worn ActiGraph was located at the center (7th) of the monitors both in the Standardized (12,252 ± 598 steps/day, mean ± SD) and free-living days (9295 ± 4027 steps/day). The correlation between the accelerometer-based devices was very high (r = 0.87–0.99). However, the steps of Yamasa was significantly lower in both trials than ActiGraph. The wrist-worn accelerometers had significantly higher steps than other devices both trials (P < 0.05). The differences between ActiGraph and Actimarker or Lifecorder was less than 100 steps/day in the Standardized day, and the differences between ActiGraph and Active Style Pro was less than 100 steps/day in the free-living days. Regression equation was also performed for inter-device compatibility.SignificanceStep obtained from the wrist-worn, waist-worn, and pocket-type activity trackers were significantly different from each other but still highly correlated in free-living conditions.  相似文献   
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《Value in health》2022,25(2):194-202
ObjectivesLifestyle interventions during pregnancy improve maternal and infant outcomes. We aimed to compare the cost-effectiveness of 4 antenatal lifestyle intervention types with standard care.MethodsA decision tree model was constructed to compare lifestyle intervention effects from a novel meta-analysis. The target population was women with singleton pregnancies and births at more than 20 weeks’ gestation. Interventions were categorized as diet, diet with physical activity, physical activity, and mixed (lacking structured diet and, or, physical activity components). The outcome of interest was cost per case prevented (gestational diabetes, hypertensive disorders in pregnancy, cesarean birth) expressed as an incremental cost-effectiveness ratio (ICER) from the Australian public healthcare perspective. Scenario analyses were included for all structured interventions combined and by adding neonatal intensive care unit costs. Costs were estimated from published data and consultations with experts and updated to 2019 values. Discounting was not applied owing to the short time horizon.ResultsPhysical activity interventions reduced adverse maternal events by 4.2% in the intervention group compared with standard care and could be cost saving. Diet and diet with physical activity interventions reduced events by 3.5% (ICER = A$4882) and 2.9% (ICER = A$2020), respectively. Mixed interventions did not reduce events and were dominated by standard care. In scenario analysis, all structured interventions combined and all interventions when including neonatal intensive care unit costs (except mixed) may be cost saving. Probabilistic sensitivity analysis showed that for physical activity and all structured interventions combined, the probability of being cost saving was 58% and 41%, respectively.ConclusionsGovernments can expect a good return on investment and cost savings when implementing effective lifestyle interventions population-wide.  相似文献   
24.
Cheryl L. Rock PhD  RD  Cynthia A. Thomson PhD  RD  Kristen R. Sullivan MS  MPH  Carol L. Howe MD  MLS  Lawrence H. Kushi ScD  Bette J. Caan DrPH  Marian L. Neuhouser PhD  RD  Elisa V. Bandera MD  PhD  Ying Wang PhD  Kimberly Robien PhD  RD  Karen M. Basen-Engquist PhD  MPH  Justin C. Brown PhD  Kerry S. Courneya PhD  Tracy E. Crane PhD  RDN  David O. Garcia PhD  FACSM  Barbara L. Grant MS  RDN  CSO  FAND  Kathryn K. Hamilton MA  RDN  CSO  CDN  FAND  Sheri J. Hartman PhD  Stacey A. Kenfield ScD  Maria Elena Martinez PhD  Jeffrey A. Meyerhardt MD  MPH  Larissa Nekhlyudov MD  MPH  Linda Overholser MD  Alpa V. Patel PhD  Bernardine M. Pinto PhD  Mary E. Platek PhD  RD  CDN  Erika Rees-Punia PhD  MPH  Colleen K. Spees PhD  MEd  RD  LD  FAND  Susan M. Gapstur PhD  Marjorie L. McCullough ScD  RD 《CA: a cancer journal for clinicians》2022,72(3):230-262
The overall 5-year relative survival rate for all cancers combined is now 68%, and there are over 16.9 million survivors in the United States. Evidence from laboratory and observational studies suggests that factors such as diet, physical activity, and obesity may affect risk for recurrence and overall survival after a cancer diagnosis. The purpose of this American Cancer Society guideline is to provide evidence-based, cancer-specific recommendations for anthropometric parameters, physical activity, diet, and alcohol intake for reducing recurrence and cancer-specific and overall mortality. The audiences for this guideline are health care providers caring for cancer survivors as well as cancer survivors and their families. The guideline is intended to serve as a resource for informing American Cancer Society programs, health policy, and the media. Sources of evidence that form the basis of this guideline are systematic literature reviews, meta-analyses, pooled analyses of cohort studies, and large randomized clinical trials published since 2012. Recommendations for nutrition and physical activity during cancer treatment, informed by current practice, large cancer care organizations, and reviews of other expert bodies, are also presented. To provide additional context for the guidelines, the authors also include information on the relationship between health-related behaviors and comorbidities, long-term sequelae and patient-reported outcomes, and health disparities, with attention to enabling survivors' ability to adhere to recommendations. Approaches to meet survivors' needs are addressed as well as clinical care coordination and resources for nutrition and physical activity counseling after a cancer diagnosis.  相似文献   
25.
《Dental materials》2022,38(6):1044-1059
ObjectiveAssess the biological and physicochemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) leachates with and without chlorhexidine (CHX).MethodsThe sealers were studied in no contact and 1-minute contact with CHX. For biological properties (antibacterial activity and cytotoxicity), leachates were formed in saline of freshly mixed, 1-, 7- and 28 days set sealers. The antibacterial properties of sealer leachates were investigated for planktonic and biofilm growth of E. faecalis, S. mutans, S.epidermidis and S.aureus. The 3-(4,5 dimethylthiazolyl-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to evaluate murine fibroblast cell viability after exposure to the leachates. The physical properties (water uptake, sorption, solubility, porosity, surface characteristics) of sealers and the pH of the immersion liquid (saline or distilled water) were also assessed over a 28-days period.ResultsCHX improved the antibacterial properties of the sealer leachates and reduced cell viability for all sealer leachates, except for freshly mixed PCS. BioRoot RCS leachates presented the highest antibacterial properties and cell viability with and without CHX contact. PCS was the material most affected by CHX in terms of physical properties, whereas for AH Plus, solubility was increased. CHX did not affect the physical properties of BioRoot RCS, except for solubility that was decreased. CHX contact did not change sealers’ alkalinity in distilled water whereas it increased it for AH Plus and BioRoot RCS in saline.SignificanceCHX improved the antibacterial efficacy of sealer leachates and either compromised or did not affect cell viability. CHX affected to various extent sealers’ physicochemical properties.  相似文献   
26.
感染控制对根管治疗的成功至关重要。尽管随着器械及设备的进步,对根管的清理及成形取得了很大的进展;然而,由于根管系统解剖结构错综复杂,使得获取清洁根管面临各种问题。例如:机械预备的宽度有限,不能彻底清理感染牙本质;冲洗技术的运用虽然可以去除根管器械预备后形成的玷污层,但对细菌内毒素的清除还是难以达到理想的效果,而残留的微生物、毒素等若得不到清除可能会在根尖周组织形成持续感染。因此,除外机械预备和冲洗,根管封药也是感染根管治疗过程中的重要步骤。氢氧化钙糊剂以其高效的抗菌作用在临床得到广泛使用。文章将对根管封药的必要性、氢氧化钙的作用机制及临床应用做一介绍。  相似文献   
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IntroductionThere is a growing interest in physical activity in relation to recovery after surgery. One important aspect of measuring recovery after surgical procedures is postoperative complications. The aim of this study was to determine if there is an association between the preoperative level of habitual physical activity and postoperative complications in patients undergoing elective surgery for colorectal cancer.Materials and methods115 patients scheduled for elective surgery due to colorectal cancer between February 2014 and September 2015 answered a questionnaire regarding physical activity and other baseline variables. Physical activity was assessed using the Saltin-Grimby physical activity level scale. Complications within 30 days after surgery were classified according to Clavien-Dindo, and the Comprehensive Complications Index (CCI) was calculated. Primary outcome was difference in CCI and key secondary outcome was risk for CCI ≥20.ResultsPhysically inactive individuals had a CCI that was 12 points higher than individuals with light activity (p = 0.002) and 17 points higher than regularly active individuals (p = 0.0004). Inactive individuals had a relative risk for a CCI ≥20 that was 65% higher than for individuals reporting light activity (95% confidence interval (CI) for relative risk (RR) = 1.1–2.5) and 338% higher than for regularly active individuals (95% CI for RR = 2.1–9.4).ConclusionSelf-assessed level of habitual physical activity before colorectal cancer surgery was associated with fewer postoperative complications measured with CCI, in a dose-response relationship.  相似文献   
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