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1.
Kui Li Jiawen Wang Shengxiong Liu Sen Su Chenjian Feng Xiaoxiang Fan Zhiyong Yin 《中华创伤杂志(英文版)》2015,18(2):65-73
Objective: To study the biomechanical mechanism of head injuries beaten with sticks, which is common in the battery or assaultive cases.
Methods: In this study, the Hybrid-III anthropomorphic test device and finite element model (FEM) of the total human model for safety (THUMS) head were used to determine the biomechanical response of head while being beaten with different sticks. Total eight Hybrid-III tests and four finite element simulations were conducted. The contact force, resultant acceleration of head center of gravity, intracranial pressure and von Mises stress were calculated to determine the different biomechanical behavior of head with beaten by different sticks.
Results: In Hybrid-III tests, the stick in each group demonstrated the similar kinematic behavior under the same loading condition. The peak values of the resultant acceleration for thick iron stick group, thin iron stick group, thick wooden stick group and thin wooden stick group were 203.4 g, 221.1 g, 170.5 g and 122.2 g respectively. In finite element simulations, positive intracranial pressure was initially observed in the frontal comparing with negative intracranial pressure in the contra-coup site. Subsequently the intracranial pressure in the coup site was decreasing toward negative value while the contra-coup intracranial pressure increasing toward positive values.
Conclusions: The results illustrated that the stiffer and larger the stick was, the higher the von Mises stress, contact force and intracranial pressure were. We believed that the results in the Hybrid-III tests and THUMS head simulations for brain injury beaten with sticks could be reliable and useful for better understanding the injury mechanism. 相似文献
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The purpose of the study was to determine if longitudinal measurements of enamel autofluorescence (quantitative light-induced fluorescence, QLF) could detect differences in remineralization of early enamel caries on buccal surfaces of anterior teeth following supervised daily brushing with either sodium fluoride (NaF; 1,450 ppm F), sodium monofluorophosphate (MFP; 1,450 ppm F) dentifrices or a herbal, non-fluoride placebo dentifrice. The study was a pragmatic cluster-randomized controlled trial with schools as the unit of randomization. Twenty-one schools in Chengdu, China, comprised the clusters; 296 children with at least 1 visible white-spot lesion were examined using QLF at baseline and after 3 and 6 months. Each of the 21 clusters was randomly assigned 1 of the 3 dentifrices, and the children brushed under supervision once per day for 2 min. The primary outcome measure was deltaQ (product of fluorescence loss and area) at a 5% threshold after 6 months of product use. A multi-level model was fitted to the data at the site level, taking into account the hierarchical structure with baseline deltaQ, age and sex as covariates. After 3 months there was a significant difference between the MFP group and placebo (p = 0.02) and after 6 months between the NaF group (p = 0.002), MFP group (p < 0.001) and the placebo. QLF methodology could detect, within 3- and 6-month periods of supervised brushing, a difference in remineralization between fluoride-containing and non-fluoride-containing dentifrices. Typically lesions in all 3 treatment groups demonstrated improvement. Groups receiving fluoride experienced a more rapid and more substantial remineralization than those in the placebo group. 相似文献
4.
The aim of this study was to determine the impact of analysis patch border inclusion or exclusion on the reliability of quantitative laser fluorescence (QLF) analyses of lesions close to the gingival margin. Ninety-three lesions on the maxillary anterior teeth were imaged using a fluorescent capturing system. All the lesions were located on the gingival third of the teeth. One examiner undertook two analyses of the images 1 week apart and another examiner undertook a single analysis. Analyses were undertaken using QLF 2.00 g with four patch borders. Each border was assessed as active or inactive. QLF metrics DeltaF, DeltaQ and area were exported. Kappa statistics were used to measure the agreement of border inclusion between all three analyses, and intra-class correlation coefficients (ICCs) were used to determine the intra- and inter-examiner reliability of the QLF metrics. Agreement on border exclusion was poor; with intra-examiner kappa of 0.48 and inter-examiner at 0.20. However, despite the inconsistencies in border exclusions the ICCs for each QLF metric were high; intra-examiner DeltaQ 0.91, DeltaF 0.80 and area 0.92; inter-examiner DeltaQ 0.86, DeltaF 0.68, area 0.88. Lesions adjacent to the gingival margin will often require a patch analysis border to be excluded in order to ensure a satisfactory reconstruction and thus accurate analysis. The decision to include or exclude a border and, if excluded, which border to select appears to be highly variable between examiners. Nevertheless, the QLF metrics appear to be robust as demonstrated by the high ICCs noted in this study. 相似文献
5.
ZHU Yuan Yue ZHENG Rui Zhi WANG Gui Xia CHEN Li SHI Li Xin SU Qing XU Min XU Yu CHEN Yu Hong YU Xue Feng YAN Li WANG Tian Ge ZHAO Zhi Yun QIN Gui Jun WAN Qin CHEN Gang GAO Zheng Nan SHEN Fei Xia LUO Zuo Jie QIN Ying Fen HUO Ya Nan LI Qiang YE Zhen ZHANG Yin Fei LIU Chao WANG You Min WU Sheng Li YANG Tao DENG Hua Cong ZHAO Jia Jun CHEN Lu Lu MU Yi Ming TANG Xu Lei HU Ru Ying WANG Wei Qing NING Guang LI Mian LU Jie Li BI Yu Fang 《Biomedical and environmental sciences : BES》2021,34(1):9-18
Objective The relationship between serum uric acid(SUA)levels and glycemic indices,including plasma glucose(FPG),2-hour postload glucose(2 h-PG),and glycated hemoglobin(HbA1 c),remains inconclusive.We aimed to explore the associations between glycemic indices and SUA levels in the general Chinese population.Methods The current study was a cross-sectional analysis using the first follow-up survey data from The China Cardiometabolic Disease and Cancer Cohort Study.A total of 105,922 community-dwelling adults aged≥40 years underwent the oral glucose tolerance test and uric acid assessment.The nonlinear relationships between glycemic indices and SUA levels were explored using generalized additive models.Results A total of 30,941 men and 62,361 women were eligible for the current analysis.Generalized additive models verified the inverted U-shaped association between glycemic indices and SUA levels,but with different inflection points in men and women.The thresholds for FPG,2 h-PG,and HbA1 c for men and women were 6.5/8.0 mmol/L,11.0/14.0 mmol/L,and 6.1/6.5,respectively(SUA levels increased with increasing glycemic indices before the inflection points and then eventually decreased with further increases in the glycemic indices).Conclusion An inverted U-shaped association was observed between major glycemic indices and uric acid levels in both sexes,while the inflection points were reached earlier in men than in women. 相似文献
6.
YE Cheng Yin LI Jin Mei WU Jing Hua LI Zheng XIAO Juan YIN Xiao Yu WANG Da Hui XU Guo Zhang YANG Lei 《Biomedical and environmental sciences : BES》2021,34(8):641-645,中插6-中插12
With a global prevalence of 7.7 million, ischemic stroke (IS) is one of the leading causes of death and disability worldwide. In China, IS alone contributed to 69.6%? of stroke events and accounted for 37.1%? of the mortality/disability rate[1]. IS is a complex disease that is known to be associated?with?various?genetic?variants?and?clinical and lifestyle risk factors[2]. Genome -wide association studies (GWAS) provided evidence for the?occurrence?of?more?than?160?IS-associated?single nucleotide?polymorphisms?(SNPs).?In?terms?of?clinical risk factors, patients with a history of chronic diseases like hypertension, dyslipidemia, and diabetes mellitus, display a higher risk of developing IS. Among the various lifestyle components, leading a sedentary lifestyle, smoking, and having an unhealthy diet are known to be associated with the risk of IS. Thus, integration of various genetic, clinical, and lifestyle variables might prove to be highly beneficial in the prediction and prevention of IS?at?the?individual?level[3]. 相似文献
7.
Hongmin Zhang Lina Zhang Lixia Liu Ying Zhu Wanhong Yin Wei He Xiuling Shang Yangong Chao Liwen Lv Xiaoting Wang Dawei Liu Chinese Critical Ultrasound Study Group 《中国医学科学杂志(英文版)》2021,36(4):257-264
Objective Focused cardiac ultrasound (FCU) and lung ultrasound (LU) are increasingly being used in critically ill patients.This study aimed to investigate the effect of FCU in combination with LU on these patients and to determine if the timing of ultrasound examination was associated with treatment change.Methods This is a multicenter cross-sectional observational study.Consecutive patients admitted to the intensive care unit (ICU) were screened for enrollment.FCU and LU were performed within the first 24 h,and treatment change was proposed by the performer based on the ultrasound results and other clinical conditions.Results Among the 992 patients included,502 were examined within 6 h of ICU admission (early phase group),and 490 were examined after 6 h of admission (later phase group).The early phase group and the later phase group had similar proportions of treatment change (48.8% vs.49.0 %,x2 =0.003,P=0.956).In the multivariable analysis,admission for respiratory failure was an independent variable associated with treatment change,with an odds ratio (OR) of 2.357[95 % confidence interval (CI):1.284-4.326,P=0.006];the timing of examination was not associated with treatment change (OR=0.725,95%CI:0.407-1.291,P=0.275).Conclusions FCU in combination with LU,whether performed during the early phase or later phase,had a significant impact on the treatment of critically ill patients.Patients with respiratory failure were more likely to experience treatment change after the ultrasound examination. 相似文献
8.
Temporal lobe epilepsy is associated with astrogliosis. Notchl signaling can induce astrogliosis in glioma. However, it remains unknown whether Notchl signaling is involved in the pathogenesis of epilepsy. This study investigated the presence of Notchl, hairy and enhancer of split-l, and glial fibrillary acidic protein in the temporal neocortex and hippocampus of lithium-pilocar- pine-treated rats. The presence of Notchl and hairy and enhancer of split-1 was also explored in brain tissues of patients with intractable temporal lobe epilepsy. Quantitative electroencephalo- gram analysis and behavioral observations were used as auxiliary measures. Results revealed that the presence of Notchl, hairy and enhancer of split-l, and glial fibriUary acidic protein were en- hanced in status epilepticus and vehicle-treated spontaneous recurrent seizures rats, but remain unchanged in the following groups: control, absence of either status epilepticus or spontaneous recurrent seizures, and zileuton-treated spontaneous recurrent seizures. Compared with patient control cases, the presences of Notch1 and hairy and enhancer of split- 1 were upregulated in the temporal neocortex of patients with intractable temporal lobe epilepsy. Therefore, these results suggest that Notchl signaling may play an important role in the onset of temporal lobe epilepsy via astrogliosis. Furthermore, zileuton may be a potential therapeutic strategy for temporal lobe epilepsy by blocking Notchl signaling. 相似文献
9.
Rapamycin, similar to FK506, can promote neural regeneration in vitro. We assumed that the mechanisms of action of rapamycin and FK506 in promoting peripheral nerve regeneration were similar. This study compared the effects of different concentrations of rapamycin and FK506 on Sc hwann cells and investigated effects and mechanisms of rapamycin on improving peripheral nerve regeneration. Results demonstrated that the lowest rapamycin concentration(1.53 nmol/L) more significantly promoted Schwann cell migration than the highest FK506 concentration(100 μmol/L). Rapamycin promoted the secretion of nerve growth factors and upregulated growth-associated protein 43 expression in Schwann cells, but did not significantly affect Schwann cell proliferation. Therefore, rapamycin has potential application in peripheral nerve regeneration therapy. 相似文献
10.
Na Q Liu C Cui H Zhang Z Yin S Li Q 《The Journal of international medical research》2011,39(6):2344-2351
This prospective study evaluated the short-term outcomes of 16 neonates undergoing single congenital omphalocele repair. Parents made informed choices for their baby to receive either immediate repair (IR group, n = 8) or repair ≥ 3 h after delivery (control group, n = 8). All babies were delivered by elective caesarian section. Babies in the two groups were matched one-to-one according to their birth weight, bulging volume and gestational age. Short-term outcomes included the incidence of infection and the lengths of stay in the neonatal intensive care unit (NICU) and in the hospital. Compared with the control group, the IR group showed a significantly lower incidence of infection, shorter surgical duration, shorter NICU stay, less time on total parenteral nutrition, less time to total enteral nutrition and shorter length of hospital stay. Immediate repair significantly improved the short-term neonatal outcomes of congenital omphalocele in China. 相似文献