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971.
Mengjie Huang Haihang Wang Gaohan Liu Heng Wei Jie Hu Yao Wang Xuezhong Gong Sui Mao Michail Danilov Ihor Rusetskyi Jianguo Tang 《Materials》2022,15(14)
The macromorphic properties of carbon nanotubes perform poorly because of their size limitations: nanosize in diameters and microsize in length. In this work, to realize these dual purposes, we first used an electrochemical method to tear the surface of multiwalled carbon nanotubes (MWCNTs) to anchor photonic Eu3+-complexes there. Through the polar reactive groups endowed by the tearing, the Eu3+-complexes coordinate at the defected structures, obtaining the Eu3+-complex-anchored, unzipped, multiwalled carbon nanotubes (E-uMWCNTs). The controllable surface-breaking retains the MWCNTs’ original, excellent mechanical properties. Then, to obtain the macromorphic structure with infinitely long fibers, a wet-spinning process was applied via the binding of a small quantity of polyvinyl alcohol (PVA). Thus, the wet-spun fibers with high contents of E-uMWCNTs (E-uMWCNT-Fs) were produced, in which the E-uMWCNTs took 33.3 wt%, a high ratio in E-uMWCNT-Fs. On the other hand, due to the reinforcing effect of E-uMWCNTs, the highest tensile strength can reach 228.2 MPa for E-uMWCNT-Fs. Meanwhile, the E-uMWCNT-Fs show high-efficiency photoluminescence and excellent media resistance performance due to the embedding effect of PVA on the E-uMWCNTs. Therefore, E-uMWCNT-Fs can exhibit excellent luminescence properties in aqueous solutions at pH 4~12 and in some high-concentration metal-ion solutions. Those distinguished performances promise outstanding innovations of this work. 相似文献
972.
Zheng Chen Xifeng Hu Xiangdong Wu Yu Li Zhen Ding Qinghua Zeng Tong Wan Jingyi Yin Huansheng Wu 《Viruses》2022,14(7)
Porcine circovirus-like virus (PCLV) is a member of circovirus that contains a single-strand DNA genome, which may be one of the pathogens that causes diarrheal symptoms in pigs. The Rep protein encoded by the genome of PCLV may be responsible for viral genome replication. The development of serological detection methods for PCLV is of great necessity for clinical diagnosis, as well as epidemiological investigations. Therefore, this study attempted to build an indirect enzyme-linked immunosorbent assay (ELISA) to examine antibodies against PCLV based on the His-tagged recombinant Rep protein. Full-length PCLV Rep protein was induced and expressed in E. coli and was purified as an antigen to establish an ELISA detection kit. The purified Rep protein was used to inject into mice to produce specific antibodies. There was no cross-reaction of Rep-based ELISA with antisera against other porcine viruses. The intra-assay and inter-assay coefficient variations (CVs) were 0.644–8.211% and 0.859–7.246%, respectively, indicating good repeatability. The non-cross-reaction with TGEV, PRRSV and PCV2 testing showed high sensitivity and high specificity for this ELISA assay. A total of 1593 serum samples collected from different pig farms in Jiangxi Province were tested for anti-PCLV Rep antibodies, and 284 (17.83%) of the 1593 samples were Rep antibody positive. Altogether, the indirect ELISA detection tool developed in this study could be applied to examine serum of PCLV antibodies with good repeatability, high sensitivity and high specificity. In addition, field sample detection results suggested that the PCLV antibody has a low prevalence in pig populations in Jiangxi Province of China. 相似文献
973.
Ruijie Yan Enying Gong Xinxuan Li Lutong Zheng Wei Liao Kaiyuan Min Fenghua Su Lianjun Wang Jing Wang Denghui Hu Yuxiang Tang Juan Zhang 《Nutrients》2022,14(14)
The excessive consumption of sugar-sweetened beverages (SSBs) has been proven to be critical for obesity among preschoolers. This study aimed to describe the SSB consumption rates among preschoolers in the Dongcheng District of Beijing, China, and to explore the association between obesogenic environmental determinants and consumption. We applied a stratified cluster sampling method and recruited 3057 primary caregivers of preschoolers in June 2019 to participate in the survey. The caregivers reported their children’s consumption rates of six categories of SSBs and their exposure rates to SSB-related obesogenic environments. The associations between them were tested using multivariate logistic regression models. The mean (SD) age of the children was 5.6 (0.6) years and nearly half (48.3%) were girls. About 84.5% of the children had consumed SSBs over the past three months, and sugar-sweetened milk beverages had the highest consumption rate. Higher exposure to advertisements for the corresponding SSB categories in children, higher frequency rates of consuming SSBs and of taking children to fast-food restaurants in caregivers, and lower frequency rates of reading the Nutrition Facts Panels by caregivers were associated with higher SSB consumption rates among children (p < 0.05 in all of the SSB categories investigated, except for the Nutrition Facts Panel reading behaviors for the sports and energy beverages). SSB consumption among preschoolers is of concern, and comprehensive policy actions and education are urgently needed. 相似文献
974.
<正>Colorectal cancer(CRC) is the third most common cancer worldwide and the second most common in tumor-related mortality by Global Cancer Statistics 2020(1). Recent data show that the incidence and mortality of CRC in China are increasing(2-4), with the number of new cases and deaths reaching 607,900 and 261,777 in 2019. 相似文献
975.
目的 不同频率下神经肌肉电刺激(neuromuscular electrical stimulation,NMES)在ARDS相关性ICU获得性衰弱(ICU-acquired weakness,ICU-AW)中的作用及机制。方法 健康雄性C57BL/6小鼠88只随机分为11组,每组8只。分为:空白对照组(C1)、气管内注入无菌水组(C2)、ICU-AW模型组(ICU-AW)、ICU-AW+AMPK激动剂A-769662组(ICU-AW-A)、ICU-AW+A-769662溶剂对照组(ICU-AWV)、NMES 20 Hz组(ICU-AW-20)、NMES 40 Hz组(ICU-AW-40)、NMES 60 Hz组(ICU-AW-60)、NMES80 Hz组(ICU-AW-80)、ICU-AW-40+AMPK抑制剂Compound C组(ICU-AW-40-C)、ICU-AW-40+Compound C溶剂对照组(ICU-AW-40-V)。检测小鼠四肢抓力和存活状态,7 d后收集小鼠肺组织和腓肠肌标本,采用HE染色观察肺和肌肉病理学变化,采用western blot以及qRT-PCR的方... 相似文献
976.
Gas wave ejectors (GWEs) utilize pressure waves to efficiently transfer energy between gases, and they have broad applications in the chemical industry. In order to improve the performance of GWEs, the influence of bending angles on GWE performance was studied and experiments involving a GWE equipped with curved channels were carried out for the first time in this study. The research results show that when the exhaust angle difference (φdout) is ≤−3.9° and the incident angle difference (φdin) is >5.0° or ≤−5.0°, the equipment performance decreases with an increase in the absolute values of the angle differences. The maximum efficiency of the backward-curved-channel device is 61.6% within the experimental range. The experimental efficiency of the curved-channel device and the static-pressure proportion of the total pressure of the medium-pressure gas are enhanced in comparison with a traditional straight-channel device, and the operating power consumption is relatively reduced. Due to the difference between the gas incident and exhaust angles, the manner in which the performance of the curved-channel device varies with the rotation speed is different depending on the working conditions.The effects of curved rotor channel for enhancing the efficiency of gas wave ejector, improving the portion of static pressure of medium-pressure gas, and reducing operating power consumption are studied by simulation and experiment. 相似文献
977.
Xinran Shen Shunna Lin Hui Li Nubiya Amaerjiang Wen Shu Menglong Li Huidi Xiao Sofia Segura-Prez Rafael Prez-Escamilla Xin Fan Yifei Hu 《Nutrients》2022,14(14)
Background: Emergency cesarean section (EMCS) and breastfeeding difficulties increase the risk of postpartum depressive (PPD) symptoms. Early initiation of breastfeeding (EIBF) may not only alleviate PPD symptoms but also facilitate subsequent breastfeeding success. EMCS is a risk factor for not practicing EIBF. Therefore, it is important to understand the relationship between EMCS, EIBF, and PPD symptoms. Methods: We conducted a prospective cohort study in three areas of China. At baseline, a total of 965 mothers completed electronic questionnaires within 72 h postpartum. Women were screened for PPD symptoms using the Edinburgh Postpartum Depression Scale (EPDS). Multivariate logistic regression was used to identify the determinants of PPD symptoms. Mediation analysis was used to determine if EIBF mediated the relationship between delivery mode or breastfeeding education source and PPD symptoms. Results: The prevalence of EIBF was 40.6%; 14% of 965 mothers experienced EMCS, and 20.4% had PPD symptoms. The risk factors for developing PPD symptoms were excessive gestational weight gain (adjusted odds ratio [aOR] = 1.55, confidence interval [95% CI]: 1.03–2.33, p = 0.037) and EMCS (aOR = 2.05, 95% CI: 1.30–3.25, p = 0.002). The protective factors for developing PPD symptoms were monthly household income over CNY 10000 (aOR = 0.68, 95% CI: 0.47–0.97, p = 0.034), EIBF (aOR = 0.49, 95% CI: 0.34–0.72, p < 0.001), and prenatal breastfeeding education from nurses (aOR = 0.46, 95% CI: 0.29–0.73, p = 0.001). EIBF indirectly affected PPD symptoms in patients who had undergone EMCS (percentage mediated [PM] = 16.69, 95% CI: 7.85–25.25, p < 0.001). The source of breastfeeding education through EIBF also affected PPD symptoms (PM = 17.29, 95% CI: 3.80–30.78, p = 0.012). Conclusion: The association between EMCS on PPD symptoms was mediated by EIBF. By providing breastfeeding education, nurses could also help alleviate PPD symptoms. 相似文献
978.
979.
脑白质高信号与上下肢运动功能障碍的相关性研究 《首都医科大学学报》2021,42(3):385-390
目的 脑白质高信号(white matter hyperintensities, WMH)作为脑小血管病(cerebral small vessel disease, cSVD)的影像学特征之一,已经被证明与步态障碍相关,而针对其对上肢运动功能影响的研究较少。本研究旨在探究WMH与上肢及下肢运动功能障碍的相关性。方法 本研究连续入组首都医科大学附属北京朝阳医院神经内科查体的受试者,收集其临床资料并对其进行头部磁共振成像(magnetic resonance imaging, MRI)检查。根据Fazekas评分将受试者分为WMH低负担组(0~2分)和WMH中-高负担组(3~6分)。通过4米步行、起立行走(Timed Up and Go, TUG)测试、简易体能测试量表(Short Physical Performance Battery, SPPB)以及Tinetti平衡与步态量表评估下肢功能;用 10次双手轮替、10次手指捏合以及10次双手握拳时间评估上肢功能。采用单因素以及多因素线性回归探究WMH和上下肢运动功能之间的相关性。结果 入选的256名受试者平均年龄为(61.6±10.1)岁。其中WMH低负担组172人(67.2%),中-高负担组84人(32.8%)。多因素线性回归分析在校正年龄、性别、身高、血管危险因素以及其他cSVD分型后,WMH中-高负担组受试者的步宽增宽(β=1.174,P=0.021)和步频增加(β=0.533,P=0.022),与步长和步速无关(β=-1.550,P=0.228;β=0.062,P=0.429)。WMH中-高负担组的受试者Tinetti得分以及SPPB试验得分明显低于低负担组(β=-1.127,P=0.000;β=-0.844,P=0.000),TUG试验用时也明显增加(β=1.518,P=0.000)。10次双手轮替、捏合以及手运动用时WMH中-高负担组也明显增加(β=0.635,P=0.021;β=0.962,P=0.000;β=0.518,P=0.020)。结论 严重WMH会造成上肢以及下肢运动功能的障碍,导致运动功能下降。对于探究WMH导致运动功能障碍的机制有一定价值。 相似文献
980.
原发性膀胱颈梗阻/原发性膀胱颈协同失调的诊断与治疗现状 《首都医科大学学报》2021,42(5):868-873
原发性膀胱颈梗阻(primary bladder neck obstruction,PBNO)/原发性膀胱颈协同失调(primary bladder neck dyssynergia,PBND)是一组病因不明的膀胱颈梗阻综合征,临床表现为排尿期症状(排尿费力、尿踌躇、尿流变细、排空不全等)、储尿期症状(尿频、尿急、尿失禁、夜尿等)或两者同时存在。影像尿动力检查(video-urodynamic study,VUDS)是诊断PBNO/PBND的金标准,PBNO/PBND特征为高压低流的排尿模式,在影像透视下可见膀胱颈未开放或开放不全。轻症患者可采取观察、药物治疗及间歇清洁自家导尿等措施进行保守治疗,保守治疗无效的患者应行经尿道膀胱颈电切术。为进一步了解PBNO/PBND及其进展,本文就相关研究进展进行综述。 相似文献