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101.
To evaluate fracture stability and complications such as infections, need for hardware removal, malunion, and nonunion when using 2.0-mm locking plating system in fixation of mandible fractures and to compare these to those associated with the 2.0-mm non-locking plating system.A prospective clinical study was conducted in a cohort of mandible fracture patients who were randomly assigned to two groups. Patients in the non-locking group were treated with 2.0-mm non-locking plating system, and those in locking group were treated with 2.0-mm locking plating system. Fracture stability, need for maxillomandibular fixation (MMF) and postoperative complications were assessed and compared.A total of 60 patients (30 in each group) were recruited. Significant differences were found between the two groups with respect to postoperative fracture stability (P = 0.001) and need for MMF (P = 0.005). Multivariate analysis revealed that type of fixation was not the only dependent variable which affected fracture stability. There were no significant differences in postoperative complications between the two groups.The 2.0-mm locking plating system provides greater stability and early functional restoration than the 2.0-mm non-locking plating system, with similar rates of postoperative complications. Thus, it can be used as a reliable and effective treatment modality for treating mandibular fractures.  相似文献   
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103.
BackgroundControl of dynamic balance in human walking is essential to remain stable and can be parameterized by the margins of stability. While frontal and sagittal plane margins of stability are often studied in parallel, they may covary, where increased stability in one plane could lead to decreased stability in the other. Hypothetically, this negative covariation may lead to critically low lateral stability during step lengthening.Research questionIs there a relationship between frontal and sagittal plane margins of stability in able-bodied humans, during normal walking and imposed step lengthening?MethodsFifteen able-bodied adults walked on an instrumented treadmill in a normal walking and a step lengthening condition. During step lengthening, stepping targets were projected onto the treadmill in front of the participant to impose longer step lengths. Covariation between frontal and sagittal plane margins of stability was assessed with linear mixed-effects models for normal walking and step lengthening separately.ResultsWe found a negative covariation between frontal and sagittal plane margins of stability during normal walking, but not during step lengthening.SignificanceThese results indicate that while a decrease in anterior instability may lead to a decrease in lateral stability during normal walking, able-bodied humans can prevent lateral instability due to this covariation in critical situations, such as step lengthening. These findings improve our understanding of adaptive dynamic balance control during walking in able-bodied humans and may be utilized in further research on gait stability in pathological and aging populations.  相似文献   
104.
Background/aimsThe aim of this study was to investigate the effect of eight weeks of core stability-based corrective exercises, on gait parameters in elite soccer players diagnosed with middle crossed syndrome.Methods15 male elite soccer players (aged 18–28) were enrolled in a same-subject intervention trial to assess if the middle crossed syndrome could be influenced through core stability exercise. Core stability-based corrective exercises were completed 3 times per week for 8 weeks and changes in gait parameters (pre- and post- intervention) were measured.ResultsThe results showed that most gait parameters including stride length (p = 0.025), gait speed (p = 0.023), number of strides (p = 0.007), length of shots (p = 0.003), and also soccer players’ height (p = 0.011) improved significantly in post-intervention in comparison to pre-intervention. Stride width in post-intervention did not show changes in comparison with pre-intervention (p = 0.083).ConclusionThe results indicate the significant effectiveness of core stability-based corrective exercises on gait parameters in those with middle crossed syndrome. By doing corrective exercises based on core stability during the study period, gait parameters in the post-intervention surpass the results in the pre-intervention in most parameters. Therefore, it is proposed that corrective exercises based on core stability is a safe and useful method for improving function in those with middle crossed syndrome and it could be used as a therapy to help players identified with this finding. In this regard, it is suggested to researchers and coaches to correct imbalances in order to achieve better results in training programs.  相似文献   
105.
BackgroundPassive and hybrid passive ankle foot orthoses (AFOs) are often prescribed in post stroke drop foot; however, the effects of these AFOs on balance related parameters in these patients seem unclear. Accordingly, the aim of current study was to evaluate the role of the newly designed hybrid passive and Posterior Leaf Spring (PLS) AFOs on balance related parameters including: self-reported balance confidence (ABC), Timed Up and Go Test (TUG) and Berg Balance Scale (BBS) in post stroke drop foot patients.MethodsFifteen post stroke drop foot patients were recruited in current study. Then, ABC, TUG and BBS were assessed with newly designed AFO and PLS AFO.ResultsThe results of this study were shown a significant improvement in ABC, TUG and BBS scores with the newly designed AFO than PLS AFO (p < 0.05).ConclusionThis study suggested that the newly designed AFO was improved the balance related parameters than PLS AFO.  相似文献   
106.
《Vaccine》2021,39(20):2791-2799
BackgroundVaccines are urgently needed to prevent the global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We assessed the safety and immunogenicity of vaccine candidate mRNA-1273, encoding the prefusion-stabilized spike protein of SARS-CoV-2.MethodsThis phase 2, randomized, observer-blind, placebo-controlled trial was conducted at 8 sites in the USA, in healthy adults aged ≥18 years with no known history or risk of SARS-CoV-2 infection, and had not previously received an investigational CoV vaccine or treatment. Participants were stratified into two age cohorts (≥18-<55 and ≥55) and were randomly assigned (1:1:1) to either 50 or 100 µg of mRNA-1273, or placebo administered as two intramuscular injections 28 days apart. The primary outcomes were safety, reactogenicity, and immunogenicity assessed by anti-SARS-CoV-2-spike binding antibody level (bAb). Secondary outcome was immunogenicity assessed by SARS-CoV-2 neutralizing antibody (nAb) response.ResultsBetween 29 May and 8 July 2020, 600 participants were randomized, 300 per age cohort. The most common solicited adverse reactions were pain at injection site, headache, and fatigue following each vaccination in both age cohorts. One serious adverse event deemed unrelated by the site investigator occurred 33 days post-vaccination one. mRNA-1273 induced bAb and nAb by 28 days post-vaccination one that were higher at the 100 µg dose relative to the 50 µg dose; this difference was less apparent post-vaccination two. Binding antibodies and nAb increased substantially by 14 days following the second vaccination (day 43) to levels exceeding those of convalescent sera and remained elevated through day 57.ConclusionsVaccination with mRNA-1273 resulted in significant immune responses to SARS-CoV-2 in participants 18 years and older, with an acceptable safety profile, confirming the safety and immunogenicity of 50 and 100 µg mRNA-1273 given as a 2 dose-regimen.ClinicalTrials.gov; NCT04405076.  相似文献   
107.
目的: 比较2015—2019年某焦化厂下风向居民不同人群血清免疫球蛋白的含量并分析其变化趋势。方法: 2015—2019年夏季,选取中国北部某焦化厂下风向(1~2 km)两个村庄的常住居民为研究群体,按照一定的纳入排除标准确定研究对象,采集其血液及尿液通过全自动生化分析仪分别检测血清免疫球蛋白(IgG、IgA和IgM)含量及尿肌酐(Cr),并对血清免疫球蛋白含量异常率进行统计分析。尿液中多环芳烃代谢物1-羟基芘的含量采用高效液相色谱-荧光法检测。结果: 2015—2019年某焦化厂下风向居民中,女性血清IgG含量均值在各年份间均高于男性(P<0.01),IgM含量均值在2015年和2016年高于男性(P<0.05);成人血清IgG和IgA含量均值在各年份间均高于未成年人(P<0.01),IgM含量均值在2016年低于未成年人(P<0.01)。2015—2019年某焦化厂下风向居民血清免疫球蛋白含量异常率总体呈先上升后下降的趋势,血清IgA和IgM在不同年份间的差异具有统计学意义(P<0.01),且2016年成人血清IgG、IgA和IgM含量异常率均高于未成年人(P<0.05),2015年和2016年女性血清IgG含量异常率高于男性(P<0.05)。2015—2019年,该地区居民尿液中多环芳烃代谢产物1-羟基芘的检出水平(用尿肌酐含量校正)中位数依次为0.468、0.797、0.678、0.169和0.021 μg/g。结论: 2015—2019年焦化厂下风向居民血清免疫球蛋白(IgG、IgA和IgM)含量具有一定的性别差异和年龄差异,其异常率总体呈现先上升后下降的趋势。  相似文献   
108.
Dental implants are used for oral rehabilitation. However, there remain risks of failure that depend on the implant stability. The objective of this study is to investigate whether quantitative ultrasound technique can be used to assess the amount of bone in contact with dental implants. Ten implants are first inserted in the bone samples. The 10 MHz ultrasonic response of each implant is measured using a dedicated device and an indicator I is derived based on the amplitude of the signal. Then, the implant is unscrewed by 2 π radians and the measurement is realized again. A statistical analysis of variance was carried out and revealed a significant effect of the amount of bone in contact with the implant on the values of I (p value < 10?5). The results indicates the feasibility of quantitative ultrasound techniques to assess implant primary stability in vitro.  相似文献   
109.
1. This study evaluated the toxicity of chronic exposure to low-level cadmium (Cd) in rats using ultra-performance liquid chromatography–mass spectrometry (UPLC–MS). Forty male Sprague–Dawley rats were randomly assigned to four groups, namely, the control group, low-dose group (0.13?mg/kg·bw), middle-dose group (0.8?mg/kg·bw) and high-dose group (4.89?mg/kg·bw). The rats continuously received CdCl2 via drinking water for 24?weeks. Serum samples were collected for metabonomics analysis. The data generated from the UPLC–MS was analysed using principal components analysis (PCA) and partial least-squares discriminant analysis (PLS-DA). PLS-DA model with satisfactory explanatory and predictive ability is capable of discriminating the treatment groups from the control group.

2. Finally, the 10 metabolites were identified and showed significant changes in some treatment groups compared with that in the control group (p?p?3. Results suggest that exposure to Cd can cause disturbances in the lipid metabolism, amino acid metabolism, nervous system, antioxidant defence system, liver and kidney function.  相似文献   
110.
The transdermal delivery of 2 fluorescent probes with similar molecular weight but different lipophilicity, into and through the skin from 2 commercially available transdermal bases, pluronic lecithin organogel, and Lipoderm® has been evaluated. First, in vitro penetration of fluorescein sodium and fluorescein (free acid) through porcine skin was evaluated. Retention and depth distribution profiles in skin were obtained by tape stripping and then followed by optical sectioning using multiphoton microscopy. The results showed that Lipoderm® led to an enhanced penetration of the hydrophilic compound, fluorescein sodium. For the lipophilic compound fluorescein (free acid), Lipoderm® performed similar to pluronic lecithin organogel base, where minimal drug was detected in either receptor phase. The skin retention and depth distribution results also showed that the hydrophilic fluorescein sodium had high skin retention with Lipoderm®, whereas fluorescein (free acid) had very low penetration and retention with increasing skin depth. Moreover, optical sectioning by multiphoton microscopy revealed an uneven distribution of probes across the skin in the x-y plane for both transdermal bases. This work showed that a hydrophilic compound has significantly increased skin penetration and retention when formulated with Lipoderm®, and the skin retention of the probe was the main determinant of its skin flux.  相似文献   
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