15 results on '"Huanmin Li"'
Search Results
2. Traditional Chinese Medicine Injections Combined With Oseltamivir for Influenza: Systematic Review and Network Meta-Analysis
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Yingying Peng, Zhe Chen, Huanmin Li, Yaowei Han, Dan Sun, Yanjiao Li, Xiaoxia Wu, Hongxiang Chen, and Xinmin Li
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Pharmacology ,Pharmacology (medical) - Abstract
Background: As a cause of respiratory tract infections in humans, influenza remains with high morbidity and mortality, with associated significant healthcare burden and increased financial burden. Traditional Chinese medicine injections (TCMIs) combined with oseltamivir (TCMIs + oseltamivir) are the representative therapeutic strategies for influenza, which is a compliant with clinical applications in China. The aim of this study was to describe the comparative efficacy and safety of TCMIs + oseltamivir in patients with influenza, based on the current evidence.Methods: PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, VIP information resource integration service platform databases, and the Chinese biomedical literature service system were searched to find randomized controlled trials where TCMIs + oseltamivir are the representative therapeutic strategies for influenza, from inception until October 2021, without language restriction. Two investigators independently screened eligibility criteria, extracted data, and appraised the risk of bias with the same criteria. We conducted a network meta-analysis using the Bayesian random method for each outcome and performed the sensitivity analysis, meta-regression, and Egger’s and Begg’s tests for the reliability and robustness of our results.Results: Thirty-one trials including 2,893 participants proved eligible and reported on four TCMIs + oseltamivir versus oseltamivir. Network meta-analysis showed Yanhuning (YHN) +oseltamivir (MD = −1.7, 95% CrI: −2.5 to −0.88; SUCRA = 0.89; low certainty of evidence) in fever disappearance time, Tanreqing (TRQ) +oseltamivir (MD = −1.9, 95% CrI: −2.8 to −1; SUCRA = 0.97; low certainty of evidence) in cough disappearance time, and Xiyanping (XYP) +oseltamivir (OR = 5.9, 95% CrI: 3.1 to 11; SUCRA = 0.82; very low certainty of evidence) in the response rate to be more efficacious than oseltamivir alone with the best SUCRA. Based on the combined SUCRA value for primary outcomes, TRQ + oseltamivir is probably better in cough disappearance time, and XYP + oseltamivir and YHN + oseltamivir may be better in fever disappearance time than others. No significant difference in safety between the treatments.Conclusion: In patients with influenza, TCMIs + oseltamivir only partially improve flu symptoms. Overall therapeutic efficacy and safety are inconclusive, based on low to very low certainty of evidence. However, the safety remains uncertain, and TCMI treatments for influenza should be considered with caution. More high-quality studies examining the efficacy and safety of TCMIs are needed.Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42021286994
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- 2022
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3. White matter lesions are associated with obstructive sleep apnea hypopnea syndrome
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Huanmin Li, Tianming Lü, Shiqi Yuan, Huan Li, Weihua Huang, and Tianrong Huang
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medicine.medical_specialty ,Supine position ,Polysomnography ,stomatognathic system ,Internal medicine ,Medicine ,Humans ,Risk factor ,Univariate analysis ,Sleep Apnea, Obstructive ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,General Medicine ,Syndrome ,medicine.disease ,Magnetic Resonance Imaging ,White Matter ,Hyperintensity ,nervous system diseases ,respiratory tract diseases ,Obstructive sleep apnea ,Neurology ,Cardiology ,Neurology (clinical) ,business ,Hypopnea ,Body mass index - Abstract
Study on the association of white matter lesions with obstructive sleep apnea hypopnea syndrome and its risk factors.A recruited study with a sample of 172 patients from the department of neurology of the Third Affiliated Hospital of Southern Medical University between 2015 and 2019.According to the univariate analysis, the independent variables whereOSAHS was an independent risk factor for WML. There was a positive relationship between WML and AHI in the supine position.AHI, apnea-hypopnea index; OSAHS, obstructive sleep apnea hypopnea syndrome; WML, white matter lesions; MRI, magnetic resonance imaging; BMI, body mass index; TSTSaO290%, SaO290% total sleep time; LSaO2, lowest oxygen saturation level; CI, confidence interval; OR, odds ratio.
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- 2021
4. Combined therapy of Xiaoer Feire Kechuan oral liquid and azithromycin for mycoplasma Pneumoniae pneumonia in children: A systematic reviewmeta-analysis
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Yingying Peng, Zhe Chen, Yanjiao Li, Qiu Lu, Huanmin Li, Yaowei Han, Dan Sun, and Xinmin Li
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Pharmacology ,Complementary and alternative medicine ,Drug Discovery ,Pneumonia, Mycoplasma ,Pharmaceutical Science ,Molecular Medicine ,Humans ,Azithromycin ,Child ,Anti-Bacterial Agents ,Drugs, Chinese Herbal ,Mycoplasma pneumoniae - Abstract
Mycoplasma pneumoniae pneumonia (MPP) has high morbidity with an increased global burden. Xiaoer Feire Kechuan (XEFRKC) oral liquid comprises multiple herbal medicines and possesses numerous broad-spectrum antibacterial activities for MPP. Therefore, treatment options with XEFRKC to provide new clinical evidence for children with MPP needs to be explored.This study aimed to evaluate the clinical efficacy and safety of combined treatment of XEFRKC with azithromycin (XEFRKC + azithromycin) for treating the MPP in children.We conducted a comprehensive search in 7 databases to find the randomized controlled trials (RCTs) of XEFRKC + azithromycin treatment. Two researchers independently review the retrieval, extraction, and quality assessment of the dataset. In addition, we conducted the effect model to analyze the data and performed the meta-regression with sensitivity analysis to assess the heterogeneity and stability.A total of 30 RCTs with 2997 participants were included in this review. The results of primary outcomes showed that the XEFRKC + azithromycin therapy was significantly different with the azithromycin in response rate (RR = 1.18, 95% CI: 1.13 to 1.22), fever disappearance time (MD = -1.01, 95% CI: -1.18 to -0.84), cough disappearance time (MD = -2.18, 95% CI: -2.69 to -1.67), and pulmonary rales disappearance time (MD = -1.3, 95% CI: -1.71 to -0.88). For secondary outcomes and safety as well, XEFRKC + azithromycin had a significant difference compared with azithromycin. Meta-regression results showed that multiple covariables were not the source of heterogeneity. Moreover, sensitivity analysis showed that the stability of the meta-analysis results remained robust.For MPP in children, the XEFRKC + azithromycin therapy may be the better option compared with azithromycin alone. However, the accuracy of safety needs to be confirmed and verified with more high-quality RCTs.
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- 2021
5. Experimental investigation on the heat transfer enhancement of steam condensation on tube with hydrophilic-hydrophobic hybrid surface
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Huanmin Li, Zhuo You, and Hao Zhang
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History ,Computer Science Applications ,Education - Abstract
The heat transfer enhancement of steam condensation on tube with hydrophilic-hydrophobic hybrid surface have been investigated comprehensively through experiment. It has been found that the steam condensation heat transfer performance on the tube with hydrophilic-hydrophobic hybrid surface has been enhanced significantly compared to that with hydrophilic surface. The results show that the steam pressure, cooling water velocity (flow rate) and non-condensable gas have influences on the steam condensation heat transfer performance on both tubes. The steam condensation heat transfer enhancement on the tube with hydrophilic-hydrophobic surfaces is due to the droplet drainage from hydrophobic stripes to hydrophilic stripes accelerating the discharge and formation of condensate from the tube. This work can be a guide for the design of enhanced condensing heat exchanger.
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- 2022
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6. Therapeutic effect of Qinglong tail-wagging acupuncture method in knee osteoarthritis and its influence on inflammatory factors
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Huanmin, Li, Yong, Zheng, Yan, Wang, Lingcheng, Meng, Yuxiao, Guo, Chao, Bian, and Peijun, Liu
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Original Article - Abstract
Objectives: This study explored and analyzed the healing effect of Qinglong tail-wagging acupuncture method in therapy of knee osteoarthritis and its influence on inflammatory factors. Methods: 93 elderly patients with acute onset of knee osteoarthritis that hospitalized from March 2017 to June 2019 were admitted and randomly separated into observation group (n=48) and control group (n=45) in line with the method of random data form. The control group was given conventional electro-acupuncture, and the observation group was treated with the qinglong tail-waving acupuncture method. The clinical efficacy, pre- and post-VAS score, Lequesne and WOMAC indexes, and changes in serum inflammatory factor levels pre-and-post treatment were compared between the two sets of subjects. Results: The overall response rate of clinical treatment in observation group was remarkably higher than that of the control group (P < 0.05). Besides, the VAS, Lequesne as well as WOMAC scores of two groups after treatment were significantly reduced than those in pre-treatment (P < 0.05), and the indexes in observation group were remarkably lower than those in control group (P < 0.05). In addition, the serum IL-6, NO and TNF-α concentration of the two sets of subjects in post-treatment reduced significantly than that in pre-treatment (P < 0.05), and the serum IL-6, NO and TNF-α concentration in observation group were remarkably decreased than those in control group (P < 0.05). Conclusion: The acupuncture method of Qinglong tail-wagging has good healing effect on remedy of elderly knee osteoarthritis. The curative method is able to improve the patients’ function of knee joint and reduce the concentration of serum inflammatory factor in patients with knew osteoarthritis.
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- 2020
7. Diagnosis of electromagnetic scattering sources based on hotspot analysis
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Chao Wang, Sheng Li, HuanMin Li, and Yan Hua
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Diffraction ,Radar cross-section ,Optics ,Geometrical optics ,Computer science ,business.industry ,Scattering ,Hotspot (geology) ,General Earth and Planetary Sciences ,Specular reflection ,Physical optics ,business ,General Environmental Science - Abstract
For electrically large targets, the scattering mechanics are specular reflection, edge diffraction, multiple reflection, etc. Multiple reflection scattering mechanics is the mainly contribution for complex targets.Diagnosis of the scattering structure which causes this mechanics is difficult to judge and orientate. In current paper, a hotspot analysis method is proposed according to the laws of physical optics and geometrical optics, which can intuitively show the contribution of different parts to the overall radar cross section (RCS), so as to judge the components which cause the strong scattering sources and to quantitatively describe the scattering mechanic of complex targets. Hotspot analysis has great application in the analysis of target electromagnetic scattering, the design and development of target simulators, and the stealth transformation of targets.
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- 2019
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8. An Efficient Method on ISAR Image Reconstruction via Norm Regularization
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Ya-Qiu Jin, Huanmin Li, An Wen Wu, and Yu Mao Wu
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Computer science ,Iterative reconstruction ,law.invention ,Inverse synthetic aperture radar ,Automatic target recognition ,law ,Norm (mathematics) ,Radar imaging ,General Earth and Planetary Sciences ,Deconvolution ,Radar ,Algorithm ,Impulse response ,General Environmental Science - Abstract
Inverse synthetic aperture radar (ISAR) imaging technology is a powerful tool to distinguish between targets with different types. The high-resolution radar image acquisition is an important basis for further automatic target recognition. In the high-frequency radar band, since the spatially collected received signals have strong sparsity in the image domain (Fourier domain), they can be downsampled and restored by corresponding norm regularization framework. When the target is electrically large, its contributions are equal to several point scatterers [also called scattering centers (SCs)]. So that the imaging process can be regarded as the summation of the point scatterers impulse response, the convolution process, and deconvolution method, the reverse process is adopted to extract the SCs from the image, where the number of SCs reflects the sparseness of ISAR image. As for the reconstruction method, while L 1 regularization is widely used, the L q (0
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- 2019
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9. Correlation of Morphology Evolution with Superior Mechanical Properties in PA6/PS/PP/SEBS Blends Compatibilized by Multi-phase Compatibilizers
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Huanmin Li, Xu-Ming Xie, and Xianwei Sui
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Polypropylene ,Materials science ,Morphology (linguistics) ,Polymers and Plastics ,Multi phase ,General Chemical Engineering ,Organic Chemistry ,Maleic anhydride ,02 engineering and technology ,Compatibilization ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Styrene ,chemistry.chemical_compound ,Monomer ,chemistry ,Chemical engineering ,0210 nano-technology - Abstract
In this study, the maleic anhydride (MAH) and styrene (St) dual monomers grafted polypropylene (PP) and poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS), i.e. PP-g-(MAH-co-St) and SEBS-g-(MAH-co-St) are prepared as multi-phase compatibilizers and used to compatibilize the PA6/PS/PP/SEBS (70/10/10/10) model quaternary blends. Both PS and SEBS are encapsulated by the hard shell of PP-g-(MAH-co-St) in the dispersed domains (about 2 μm) of the PA6/PS/PP-g-(MAH-co-St)/SEBS (70/10/10/10) quaternary blend. In contrast, inside the dispersed domains (about 1 μm) of the PA6/PS/PP/SEBS-g-(MAH-co-St) (70/10/10/10) quaternary blend, the soft SEBS-g-(MAH-co-St) encapsulates both the hard PS and PP phases and separates them. With increasing the content of the compatibilizers equally, the morphology of the PA6/PS/(PP+PP-g-(MAH-co-St))/(SEBS+SEBS-g-(MAH-co-St)) (70/10/10/10) quaternary blends evolves from the soft (SEBS+SEBS-g-(MAH-co-St)) encapsulating PS and partially encapsulating PP (about 1 μm), then to PS exclusively encapsulated by the soft SEBS-g-(MAH-co-St) and then separated by PP-g-(MAH-co-St) inside the smaller domains (about 0.6 μm). This morphology evolution has been well predicted by spreading coefficients and explained by the reaction between the matrix PA6 and the compatibilizers. The quaternary blends compatibilized by more compatibilizers exhibit stronger hierarchical interfacial adhesions and smaller dispersed domain, which results in the further improved mechanical properties. Compared to the uncompatibilized blend, the blend with both 10 wt% PP-g-(MAH-co-St) and 10 wt% SEBS-g-(MAH-co-St) has the best mechanical properties with the stress at break, strain at break and impact failure energy improved significantly by 97%, 71% and 261%, respectively. There is a strong correlation between the structure and property in the blends.
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- 2018
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10. Polyolefin-functionalized graphene oxide and its GO/HDPE nanocomposite with excellent mechanical properties
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Huanmin Li and Xu-Ming Xie
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Glycidyl methacrylate ,Materials science ,Nanocomposite ,Graphene ,Maleic anhydride ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Styrene ,Polyolefin ,law.invention ,chemistry.chemical_compound ,Monomer ,chemistry ,Chemical engineering ,law ,Polymer chemistry ,High-density polyethylene ,0210 nano-technology - Abstract
To prepare GO/Polyolefin nanocomposites with enhanced mechanical, electrical, or thermal properties is still a challenge due to the poor interfacial adhesion between GO and non-polar polyolefins. In this study, we report an effective strategy for the polyolefin-functionalized graphene oxide (fGO) using two-step methods GO was firstly modified by using glycidyl methacrylate (GMA) and styrene (St) dual monomers grafting method, thus GO- g -(GMA- co -St) with numerous epoxide groups is obtained. Then through the reaction between the epoxide group of GMA and anhydride group of maleic anhydrides (MAH) of the prepared HDPE- g -(MAH- co -St), GO- g -HDPE- g -(MAH- co -St) could be obtained. The successful preparation of the GO- g -HDPE- g -(MAH- co -St) was confirmed by AFM, TEM, FTIR, XRD, DSC, and TGA characterization. The results show the grafting ratios of the poly(GMA- co -St) and HDPE- g -(MAH- co -St) being up to 50.4 wt% and 70.4 wt%, respectively. The functionalized GO shows homogeneous dispersion in the nanocomposites with HDPE, and the stress at break and strain at break of the nanocomposite is increased by 28.7% and 130% respectively with only 0.2 wt% fGO loading. The approach of the polyolefin-functionalized GO paves a new way to develop not only polyolefin/graphene nanocomposites but also excellent nanocomposites of polyolefin/engineering plastic blends with graphene.
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- 2018
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11. High-strength and super-tough PA6/PS/PP/SEBS quaternary blends compatibilized by using a highly effective multi-phase compatibilizer: Toward efficient recycling of waste plastics
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Xianwei Sui, Huanmin Li, and Xu-Ming Xie
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chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Multi phase ,Organic Chemistry ,Maleic anhydride ,02 engineering and technology ,Compatibilization ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Styrene ,chemistry.chemical_compound ,Brittleness ,Monomer ,chemistry ,Chemical engineering ,Materials Chemistry ,Polymer blend ,Composite material ,0210 nano-technology - Abstract
It is well known that polyolefins, styrene polymers and engineering plastics occupy the largest share of the plastic market and constitute nearly 80% of the world's plastic. However, these plastics are usually used or recycled in mixed state and immiscible with each other. It is hard to define or separate these plastics, respectively, from recycled materials. In this letter, a maleic anhydride (MAH) and styrene (St) dual monomers grafted poly [styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS), SEBS-g-(MAH-co-St) was developed as a multi-functionalized compatibilizer for combining engineering plastics, styrene polymers and polyolefins. With the help of the compatibilizer, the model quaternary blend PA6/PS/PP/SEBS (70/10/10/10) transforms from brittle into tough blends, and shows controllable morphologies and significantly improved mechanical properties. This highly efficient compatibilization strategy casts new light on both the development of high-performance multi-phase polymer blends and the recycling of waste plastics.
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- 2017
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12. Morphology development and superior mechanical properties of PP/PA6/SEBS ternary blends compatibilized by using a highly efficient multi-phase compatibilizer
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Huanmin Li and Xu-Ming Xie
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Materials science ,Polymers and Plastics ,Scanning electron microscope ,Organic Chemistry ,Maleic anhydride ,02 engineering and technology ,Compatibilization ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Agglomerate ,Phase (matter) ,Materials Chemistry ,Particle ,Polymer blend ,Composite material ,0210 nano-technology ,Ternary operation - Abstract
Multi-phase compatibilizers are potentially attractive, not only for the preparation of ternary or multi-phase immiscible polymer blends with high performance, but also for recycling and reuse of waste plastics mixture. In this study, the maleic anhydride (MAH) and styrene (St) dual monomers grafted PP, PP-g-(MAH-co-St) is prepared as a multi-phase compatibilizer, which exhibits highly effective compatibility on the PP/PA6/SEBS (70/15/15) ternary blends. Scanning electron microscopy (SEM) reveals that, with increasing the compatibilizer, the morphology evolves from the individual PA6 particle encapsulated by SEBS to several smaller-size PA6 particles partially encapsulated by SEBS phase, then to the tiny PA6 particles and some larger-size SEBS agglomerates predominantly dispersed separately in PP matrix. The morphology development predicted by spreading coefficients shows a consummate consistency with that observed by SEM. Moreover, the good compatibilization and corresponding morphologies result in superior enhancement of mechanical properties. Compared to the uncompatibilized blend, adding 15 wt% multi-phase compatibilizer to the blend leads to the best mechanical properties with the yield stress, stress at break, strain at break and impact failure energy improved significantly by 23%, 132%, 647% and 220%, respectively. The results verify that the domains with small-size PA6 particles (0.3–0.4 μm) partially encapsulated by SEBS (0.5–0.7 μm) in PP matrix are very effective to enhance the mechanical properties of the blends. The morphologies of large-size PA6 particles encapsulated by SEBS or tiny PA6 particles and some larger-size SEBS agglomerates dispersed separately in PP matrix for the enhancement in mechanical properties of the blends are very limited. Consequently, the enhanced interfacial interactions and the morphology with the rigid particles partially encapsulated by a rubber-like phase in matrix are crucial for the ternary polymer blends.
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- 2017
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13. [Correlation of apolipoprotein AI, apolipoprotein B and their ratio with the severity of cerebral white matter lesions]
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Weihua, Huang, Tianming, Lv, Huanmin, Li, Shuhua, Du, Canhong, Yang, and Shiqi, Yuan
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Analysis of Variance ,Brain Diseases ,临床研究 ,Apolipoprotein A-I ,Risk Factors ,nutritional and metabolic diseases ,Humans ,lipids (amino acids, peptides, and proteins) ,Magnetic Resonance Imaging ,Severity of Illness Index ,White Matter ,Apolipoproteins B - Abstract
OBJECTIVE: To investigate the correlation of apolipoprotein AI (ApoAI), ApoB, ApoB/ApoAI and the severity of brain white matter lesions (WML). METHODS: A total of 648 patients with WML confirmed by brain magnetic resonance imaging (MRI) were divided into mild WML group (n=386) and moderate to severe WML group (n=262) according to evaluations with the Fazekas scale. The demographic data, blood biochemical parameters and the levels of ApoAI, ApoB and ApoB/AI ratio were compared between the two groups to identify the risk factors of moderate to severe WML. RESULTS: Univariate analysis showed that age, gender, hypertension, diabetes, coronary heart disease, previous stroke, homocysteine, HDL-C, ApoAI, and ApoB/AI ratio all differed significantly between the two groups (P < 0.05), but ApoB levels were similar between them (P > 0.05). Multivariate logistic regression analysis revealed that with ApoAI and ApoB/AI ratio as the continuous variables, after adjustment for the compounding factors, ApoB/AI ratio was an independent risk factor (OR=11.456, 95%CI: 3.622-36.229, P < 0.001) and ApoAI was an independent protective factor for moderate to severe WML (OR=0.068, 95%CI: 0.018-0.262, P < 0.001). With the upper quartiles of ApoAI level (1.38 g/L) and ApoB/AI ratio (0.58) as their respective cutoff values, patients with a high ApoAI level and a low ApoB/AI ratio were found to have the lowest incidence of moderate to severe WML (P < 0.001). CONCLUSION: An increased ApoB/AI ratio is an independent risk factor and an increased ApoAI level is an independent protective factor for moderate to severe WML.
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- 2018
14. Maintaining Cooperation within Competition: The Inevitable Path of China’s Energy Cooperation in the Middle East
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Xuewen Qian and Huanmin Li
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Competition (economics) ,chemistry.chemical_compound ,Politics ,Middle East ,chemistry ,business.industry ,Energy (esotericism) ,Petroleum ,Business ,International trade ,China ,Oil and natural gas ,Foreign market - Abstract
The multi-polarization of political situation creates beneficial conditions for Chinese petroleum corporations to enter foreign market of prospecting and drilling of oil and natural gas resources. ...
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- 2009
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15. Synthesis and kinetic evaluation of a trifunctional enzyme mimic with a dimanganese active centre
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Nan Gao, Junqiu Liu, Quanshun Li, Guimin Luo, and Huanmin Li
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Antioxidant ,medicine.medical_treatment ,In Vitro Techniques ,Biochemistry ,Inorganic Chemistry ,Superoxide dismutase ,chemistry.chemical_compound ,Mice ,Coordination Complexes ,medicine ,Animals ,Humans ,chemistry.chemical_classification ,Reactive oxygen species ,Glutathione Peroxidase ,Manganese ,biology ,Superoxide Dismutase ,Glutathione peroxidase ,Molecular Mimicry ,Glutathione ,Hydrogen Peroxide ,Catalase ,chemistry ,biology.protein ,Enzyme mimic ,Steady state (chemistry) ,Lipid Peroxidation ,Rabbits ,Mitochondrial Swelling - Abstract
Glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT) play crucial roles in the metabolism and homeostasis of reactive oxygen species (ROS) in living organisms. From examination of the steady state and pre-steady state kinetic behavior of natural GPX it was found that, in contrast to accepted theories, the affinity of the enzyme for H 2 O 2 rather than reduced glutathione (GSH) most significantly affects its kinetic behavior. Consequently, an enzyme mimic was produced with a similar affinity for the substrate H 2 O 2 . A salicylaldehyde Schiff base containing a dimanganese centre was selected as a precursor, because it has high H 2 O 2 -binding affinity for such a relatively small molecule and similar catalytic activity to that of SOD and CAT. Selenium was also incorporated into the catalytic center to provide activity similar to that of GPX, and thus trifunctional enzymatic activity. The K m H2O2 of the mimic (7.32 × 10 -2 mM) was found quite close to that of natural enzyme (1.0 × 10 -2 mM), indicating that the affinity of the mimic to H 2 O 2 was successfully increased to approach natural GPX. The steady state kinetic performance of the enzyme mimic showed that the ratio between k cat /K mGSH and k cat / K mH2O2 was quite similar to that of native GPX, indicating that the Mn(III) 2 ( L -Se-SO 3 Na) had the same selectivity for both substrates GSH and H 2 O 2 as native GPX, which put it among the best existing GPX mimics. Moreover, the new mimic was confirmed to strongly inhibit lipid peroxidation and mitochondrial swelling, probably due to the synergism between the three antioxidant enzymatic activities.
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- 2010
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