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Diet and physical activity influence the composition of gut microbiota,benefit on Alzheimer's disease
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作者 Jinyue Zhou Min Tang +4 位作者 Wanyi Li Rui Fang Chunlan Tang Qinwen Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期541-555,共15页
Alzheimer's disease is a neurodegenerative disease with complex etiology.Gut microbiota influences the gutbrain axis,which may affect pathways related to the pathogenesis of Alzheimer's disease.Additionally,di... Alzheimer's disease is a neurodegenerative disease with complex etiology.Gut microbiota influences the gutbrain axis,which may affect pathways related to the pathogenesis of Alzheimer's disease.Additionally,diet and physical activity are likely to affect the pathology of Alzheimer's disease as well as the gut microbiota.This demonstrates that it may be possible to prevent or halt the progression of Alzheimer's disease by regulating the gut microbiota using diet and physical activity strategies.Therefore,the present study reviews the association between these two interventions and gut microbiota in the human body.It also summarizes how these two interventions benefit Alzheimer's disease.Furthermore,the primary limitations of these two interventions are discussed and promising strategies are proposed,which may be beneficial to further study and develop the intervening measure for the progression of Alzheimer's disease. 展开更多
关键词 Alzheimer’s disease Gut microbiota Brain-gut axis DIET Physical activity
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Assessment of perianal fistulizing Crohn’s disease activity with endoanal ultrasound: A retrospective cohort study
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作者 Na Hong Wei-Yong Liu +6 位作者 Jin-Long Zhang Kai Qian Jie Liu Xian-Jun Ye Fei-Yan Zeng Yue Yu Kai-Guang Zhang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2494-2502,共9页
BACKGROUND Perianal fistulas pose dual challenges to Crohn's disease(CD)patients.Low patient compliance due to the complexity of existing examination methods plagues the treatment and follow-up management of peria... BACKGROUND Perianal fistulas pose dual challenges to Crohn's disease(CD)patients.Low patient compliance due to the complexity of existing examination methods plagues the treatment and follow-up management of perianal CD.AIM To determine the accuracy of endoanal ultrasound(EUS)and shear wave elastography(SWE)for evaluating perianal fistulizing CD(PFCD)activity.METHODS This was a retrospective cohort study.A total of 67 patients from August 2022 to December 2023 diagnosed with CD were divided into three groups:Non-anal fistula group(n=23),low-activity perianal fistulas[n=19,perianal disease activity index(PDAI)≤4],high-activity perianal fistulas(n=25,PDAI>4)based on the PDAI.All patients underwent assessments including EUS+SWE,pelvic magnetic resonance[pelvic magnetic resonance imaging(MRI)],C-reactive protein,fecal calprotectin,CD activity index,PDAI.RESULTS The percentage of fistulas indicated by pelvic MRI and EUS was consistent at 82%,and there was good consistency in the classification of perianal fistulas(Kappa=0.752,P<0.001).Significant differences were observed in the blood flow Limberg score(χ^(2)=8.903,P<0.05)and shear wave velocity(t=2.467,P<0.05)between group 2 and 3.Shear wave velocity showed a strong negative correlation with magnetic resonance novel index for fistula imaging in CD(Magnifi-CD)score(r=-0.676,P<0.001),a weak negative correlation with the PDAI score(r=-0.386,P<0.05),and a weak correlation between the Limberg score and the PDAI score(r=0.368,P<0.05).CONCLUSION EUS combined with SWE offers a superior method for detecting and quantitating the activity of perianal fistulas in CD patients.It may be the ideal tool to assess PFCD activity objectively for management strategies. 展开更多
关键词 Endoanal ultrasound shear wave elastography Perianal fistulizing Crohn’s disease Perianal disease activity index
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Strengthening Active Aging through Older People’s Association and Economic Activity of the Older People in Nepal
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作者 Hom Nath Chalise James Brightman 《Advances in Aging Research》 CAS 2024年第2期15-24,共10页
Aging is a natural lifelong process ending in death. Many older people are living in poverty. Older people are generally considered dependent on others as they grow older. The purpose of this article is to explore the... Aging is a natural lifelong process ending in death. Many older people are living in poverty. Older people are generally considered dependent on others as they grow older. The purpose of this article is to explore the entrepreneurship activities of Nepalese older adults. Data for this study were collected from the project Help Age International (HAI) implemented in Nepal. Qualitative data observations and interviews were used to collect data. The findings of this study show the formation of the Older People’s Association (OPA) has supported many older people to participate outside the home in various social activities. Moreover, regular deposits through OPAs offer little help. OPAs support older people in their need of financial support to implement minor entrepreneurship. Older people who received support were pleased and were actively involved in their activities and also regularly deposited money in them. Subsequently, older people’s participation in social activities has increased and also helped to lower elderly abuse, loneliness, and depression. Local governments should promote such activities which will help with healthy aging. 展开更多
关键词 Aging in Nepal active Aging Older People’s Association Older People Healthy Aging
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Research on Children’s Game Activity Design Strategies Based on Embodied Cognition Theory
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作者 Xiangmiao He 《Journal of Contemporary Educational Research》 2024年第4期54-58,共5页
Edutainment,in the kindergarten education stage,emphasizes the game as the basic activity and combines the content of education with the form of the game,thus it also forms the educational method of gamification teach... Edutainment,in the kindergarten education stage,emphasizes the game as the basic activity and combines the content of education with the form of the game,thus it also forms the educational method of gamification teaching.Through investigation and analysis,it is found that the current kindergarten game activity design has the problem of improper combination of educational content and game form.The current kindergarten game activity design has problems such as stereotypes,children’s lack of active learning opportunities in activities,teachers’insufficient theoretical understanding,inappropriate teacher guidance methods,and so on.Embodied cognition theory attaches importance to the important role of the body in the development of cognition,provides new guidance for classroom teaching,and opens up a new path for classroom teaching reform.Based on the perspective of embodied cognition theory,the concept of body and mind integration should be adhered to in kindergarten teaching with games as the basic activity,experiential teaching situation should be created,children’s subjective experience should be respected,and games and interactions should be designed to promote children’s physical and mental participation,thus laying a foundation for the realization of children’s individual freedom,autonomy,and all-round development.Therefore,this paper aims at the existing problems in the current kindergarten gamification teaching and discusses the design strategy of children’s game activities based on embodied cognition theory. 展开更多
关键词 Embodied cognition Children’s play Game activity design
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Measurement and Study of Tyrosinase Activity in Potato 被引量:1
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作者 王宁芳 《Agricultural Science & Technology》 CAS 2011年第6期799-800,804,共3页
[Objective] The paper was to study the activity of tyrosinase,so as to provide reference for preventing browning of potatoes as well as fruits and vegetables containing tyrosinase.[Method] With potato as raw material ... [Objective] The paper was to study the activity of tyrosinase,so as to provide reference for preventing browning of potatoes as well as fruits and vegetables containing tyrosinase.[Method] With potato as raw material and Na2HPO4-HCl in buffer solution(pH=7.2)as system,spectrophotometer was used to measure the absorbance of potato extract at 480nm,the curve was established,and the activity of tyrosinase was obtained.[Result] The changes of data were little under the above conditions,and the stability of tyrosinase activity was high.[Conclusion] Using spectrophotometry to determine the tyrosinase activity in potato is simple with high accuracy. 展开更多
关键词 tyrosinase ABsORBANCE Kinetic curve activity
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Study on Extraction and Catalytic Activity of Tyrosinase
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作者 王宁芳 《Agricultural Science & Technology》 CAS 2016年第12期2893-2895,共3页
Objective] Tyrosinase is a kind of polyphenol oxidase used widely, and the study of tyrosinase attracts extensive attention. [Method] ln this experiment, A conversion kinetic curve of dopa solution was obtained using ... Objective] Tyrosinase is a kind of polyphenol oxidase used widely, and the study of tyrosinase attracts extensive attention. [Method] ln this experiment, A conversion kinetic curve of dopa solution was obtained using absorbance of potato extract at 480 nm in Na2HPO4-HCl buffer system at a pH value of 7.2 with the vari-ation rate of absorbance against time (ΔA/Δt) as reaction rate, and the activity of tyrosinase could thus be calculated. [Result] The results showed that at the wave-length, in the Na2HPO4-HCl buffer system with a pH value at 7.2, there was little in-terference to the system, the data showed smal fluctuations, and the activity of ty-rosinase was high and stable, further providing a theoretical foundation for the de-termination and study of factors influencing tyrosinase activity. [Conclusion] The catalytic activity of tyrosinase was studied and determined with buffer solution as substrate with high accuracy and good effect. 展开更多
关键词 ABsORBANCE Kinetic curve tyrosinase activity
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Phenol content,antioxidant and tyrosinase inhibitory activity of mangrove plants in Micronesia 被引量:2
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作者 Sung-Suk Suh Jinik Hwang +2 位作者 Mirye Park Heung-Sik Park Taek-Kyun Lee 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第7期531-535,共5页
Objective:To find out and compare the in vitro antioxidant and tyrosinase inhibitory activities of two species of mangrove plants.Methods:Mangrove samples were harvested at the shoreline on the island of Weno,Chuuk St... Objective:To find out and compare the in vitro antioxidant and tyrosinase inhibitory activities of two species of mangrove plants.Methods:Mangrove samples were harvested at the shoreline on the island of Weno,Chuuk State in Micronesia.The phenol content,antioxidant activity(based on DPPH-free radical scavenging)and tyrosinase inhibitory activity in different tissues(leaves,barks and roots)of Rhizophora stylosa(R.stylosa)and Sonneratia alba(S.alba),collected from the island of Weno.Results:Total phenol content ranged from 4.87 to 11.96 mg per g of freeze dried samples.The highest antioxidant activity was observed in R.styiosa bark(85.5%).The highest tyrosinase inhibitory activity was found in S.alba bark.Also,total phenol content and antioxidant activity were higher in methanol extracts than in aqueous extracts.Conclusions:Taken together,the results of this study proved that mangroves can be excellent sources of antioxidant compounds. 展开更多
关键词 RHIZOPHORA stylosa sONNERATIA alba Phebolics ANTIOXIDANT activity tyrosinase inhibitory activity
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Studying on Tyrosinase Inhibition Activity of Some Vietnamese Folk Plants Aims to Use in Skin-Whitening Cosmetics 被引量:1
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作者 Nguyen Thi My Hanh Nguyen Kim Phi Phung Quach Ngo Diem Phuong 《American Journal of Plant Sciences》 2017年第6期1319-1328,共10页
White mulberry Morus alba and jackfruit Artocarpus heterophyllus are two of seven chosen Vietnamese folk plants which showed the highest tyrosinase inhibition activity. Besides, both of them showed antioxidant and ant... White mulberry Morus alba and jackfruit Artocarpus heterophyllus are two of seven chosen Vietnamese folk plants which showed the highest tyrosinase inhibition activity. Besides, both of them showed antioxidant and antibacterial activities. Especially, the Sulforhodamine B (SRB) assay test result of the root core extract of M. alba figured out its non-toxicity on foreskin fibroblasts. 展开更多
关键词 MORUs ALBA tyrosinase Inhibition activity Antibacterial Antioxidant
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Antioxidant and Anti-Tyrosinase Activity from Olea Leaf Extract Depended on Seasonal Variations and Chromagraphy Treatment
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作者 Dao-Mao Yang Ming-An Ouyang 《International Journal of Organic Chemistry》 2012年第4期391-397,共7页
In the present study, olive leaf extract, harvested from four seasons, extracted with solvent (methanol and water), was treated by D101 and Sephadex LH-20, and divided into 10 fractions by TLC detection. The antioxida... In the present study, olive leaf extract, harvested from four seasons, extracted with solvent (methanol and water), was treated by D101 and Sephadex LH-20, and divided into 10 fractions by TLC detection. The antioxidant activity was evaluated using DPPH, superoxide anion scavenging and reducing power assays. Tyrosinase inhibitory activity was also performed with L-DOPA as substrate. On extraction method, there is no significant difference in methanol and water. Among 12 months, autumn showed the best harvest time in whole. OLE showed 90% tyrosinase inhibitory activity and inhibition type was non-competitive competition. By chromagraphy treatment, the ingredients of polysacchmaride and protein showed high bioactivity towards antioxidant and anti-tyrosinase activity, the rest part showed different extent of activity and prove some effect by chromatography treatment indirectly. OLE might be a valuable bioactive source and can be applicable in both the cosmetic and medical use. 展开更多
关键词 Olive Leaf Extract ANTIOXIDANT activity tyrosinase Inhibitory activity Non-CompetitiveCompetition Chromagraphy TREATMENT
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Development and assessment of tyrosinase inhibitory activity of liposomes of Asparagus racemosus extracts
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作者 Narin Therdphapiyanak Montree Jaturanpinyo +2 位作者 Neti Waranuch Lalana Kongkaneramit Narong Sarisuta 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2013年第2期134-142,共9页
The purpose of this study was to develop liposomal formulations of Asparagus racemosus root extract(AR1-6)as well as evaluate the physicochemical properties and in vitro tyrosinase inhibitory activity.Liposomes compos... The purpose of this study was to develop liposomal formulations of Asparagus racemosus root extract(AR1-6)as well as evaluate the physicochemical properties and in vitro tyrosinase inhibitory activity.Liposomes composed of AR1-6 to lipid weight ratio of 1:10 and lecithin(LEC)or Phospholipon90G(PC90G)as structural phospholipid at 7:3 molar ratio to CHOL were prepared by various methods,i.e.chloroform-film(CF),reverse-phase evaporation(REV),polyol dilution(PD),and freeze-drying of monophase solution(MFD)methods.The results revealed that vesicles prepared by CF and MFD were multilamellar whereas those prepared by REV and PD were oligolamellar in nature with particle sizes ranging from 0.26 to 13.83 mm.The zeta potentials were in the range of1.5 to39.3 mV.AR1-6 liposomes with LEC possessed significantly higher entrapment than those with PC90G.The highest entrapment efficiency and in vitro tyrosinase inhibitory activity of 69.08%and 25%,respectively,were obtained from liposomes having LEC and prepared by PD method.The tyrosinase inhibitory activity were in the rank order of LEC>PC90G,and PD>CF>REV>MFD.It could be concluded that the mechanism of vesicle forming in each method of preparation was the key factor influencing physicochemical properties,particularly vesicle type,size,surface charge,and entrapment,which were well correlated with the biological activity. 展开更多
关键词 Asparagus racemosus Liposomes Lipid composition Method of preparation tyrosinase inhibitory activity
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Inflammatory bowel diseases patients suffer from significant low levels and barriers to physical activity:The“BE-FIT-IBD”study 被引量:4
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作者 Antonietta Gerarda Gravina Raffaele Pellegrino +9 位作者 Tommaso Durante Giovanna Palladino Rossella D’Onofrio Simone Mammone Giusi Arboretto Salvatore Auletta Giuseppe Imperio Andrea Ventura Mario Romeo Alessandro Federico 《World Journal of Gastroenterology》 SCIE CAS 2023年第41期5668-5682,共15页
BACKGROUND The place regular physical activity(PA)should occupy in managing patients with inflammatory bowel diseases(IBD)is unclear.AIM To assess PA levels and barriers in a southern Italian IBD population.METHODS IB... BACKGROUND The place regular physical activity(PA)should occupy in managing patients with inflammatory bowel diseases(IBD)is unclear.AIM To assess PA levels and barriers in a southern Italian IBD population.METHODS IBD patients with non-severe disease activity[assessed with partial Mayo score for ulcerative colitis(UC)and Harvey-Bradshaw index for Crohn’s disease]were approached to receive an anonymous online questionnaire to assess PA levels using the International Physical Activity Questionnaire(IPAQ)and to assess disease activity as patient-reported outcomes 2(PRO-2)and finally to assess habits,beliefs and barriers in conducting regular PA.Clinical,anthropometric and demographic data of patients were also collected.PA was expressed as continuous units of resting metabolic rate(Met)in min/wk.Three PA groups were identified:Inactive(<700 Met min/wk),sufficiently active(700-2500 Met min/wk)and health enhancing PA(HEPA)(i.e.,HEPA active,>2500 Met min/wk)patients.RESULTS Included patients(219)showed overall PA levels of 834.5 Met min/wk,with a large proportion(94,42.9%)classified as inactive while only a minority(9,4.1%)as health-enhancing PA.Patients without dyslipidaemia(P<0.0001)or on biologics therapy(P=0.022)showed better IPAQ scores in moderate activities.UC PRO-2 correlated negatively with IPAQ intense activities scores(τ=-0.156,P=0.038).PRO-2 did not show notable sensitivity/specificity in predicting IPAQ inactivity(AUC<0.6).IBD activity did not differ between active and inactive patients(P>0.05).Active patients expressed the need to discuss PA with their gastroenterologist.Some barriers(e.g.,diagnosis of IBD and fear of flare-ups after PA)are significantly more reported by inactive patients.CONCLUSION A significant rate of physical inactivity was recorded in this setting.IPAQ showed good feasibility.PA should be an element of discussion in IBD visits assessed quickly with non-invasive questionnaires. 展开更多
关键词 Crohn’s disease Inflammatory bowel disease International Physical activity Questionnaire Physical activity Ulcerative colitis
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Verification of the Physiological Therapeutic Effects of Harvesting Activities in a Patient with Moderate Alzheimer’s Disease with Long-Term Agricultural Experience
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作者 Kikuo Eguchi Seigo Koura +1 位作者 Nao Eguchi Akihiko Kondou 《Open Journal of Therapy and Rehabilitation》 2024年第3期236-244,共9页
Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting ac... Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting activities as a part of their treatment. The patients became calmer and began to smile not only after but also before and during harvesting activity. Therefore, this study aimed to measure autonomic nervous system (ANS) responses over time in a female patient in her 80s with moderate Alzheimer’s disease (AD) who had experience in farming when performing harvesting activities. Additionally, this study aimed to consider factors associated with changes in ANS responses over time and to verify the physiological therapeutic effects of harvesting activities. Methods: An OT with more than 10 years of experience and a good relationship with the patient conducted one-on-one sessions with the patient. Harvesting activity was performed in a courtyard with trees. The patient harvested lettuce (three lettuce plants) grown in a planter while sitting on a chair. Additionally, the planter was set up on a desk. ANS responses were measured over time from before to after the activity for different events at six time periods. Changes in the patient’s ANS responses were assessed during each period. Results: With the involvement of environmental factors and OT during harvesting activities, parasympathetic nervous system (PNS) activity significantly increased. This may lead to improved mental stability. Conclusion: The findings of this study indicate that implementing harvesting activities may have a positive effect on the PNS in patients with AD with long-term agricultural experience. However, further studies with a larger sample size and multidimensional evaluations are needed. 展开更多
关键词 Alzheimer’s Disease Autonomic Nervous Response Harvesting activity Therapeutic Effects
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In Vitro Evaluation of the Antifungal Activity of Essential Oils of Thymus vulgaris and Cymbopogon citratus on Some Strains of Sclerotinia sclerotiorum, Agent Responsible for White Rot of Beans
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作者 Serge Bertrand Mboussi Alain Heu +2 位作者 Abdou Nourou Kone Nsangou Jules Patrice Ngoh Dooh Zachée Ambang 《Agricultural Sciences》 2023年第8期1068-1086,共19页
The present work was aimed to the study of the antifungal activity of essential oils of two aromatic plants against three strains of Sclerotinia sclerotiorum responsible for white rot of bean. The two essential oils (... The present work was aimed to the study of the antifungal activity of essential oils of two aromatic plants against three strains of Sclerotinia sclerotiorum responsible for white rot of bean. The two essential oils (EO) of the studied plants: Thymus vulgaris (HET) and Cymbopogon citratrus (HEC), used at different concentrations: C1 (0.75 ml/ml), C2 (1.5 ml/ml) and C3 (3 ml/ml) presented significant inhibitory activities on the three tested fungal strains namely Bia 1, Bia 2, and Njo 2. Two control treatments (T-: containing no antifungal substance and T+: synthetic fungicide) were also used. The antifungal activity here is related to the inhibition of mycelial growth especially with high concentrations of essential oils. Thus, against S. sclerotiorum, HET showed the highest activity comparable to that of T+ (100% inhibition) at all concentrations on the Bia 1 and Bia 2 strains and at concentration C3 on the Njo 2 strain compared to that of HEC, which certainly inhibited the mycelial growth of the different strains considerably (with a maximum of 78.15% on the Njo 2 strain) but not completely. According to their sensitivity, the Bia 2 strain showed a higher sensitivity to essential oils than the others while the Njo 2 strain was more aggressive. On the basis of MIC<sub>50</sub> and MIC<sub>90</sub> obtained on the Njo 2 strain, the HET turns out to be the most efficient with respective lower values of (1.73 and 23.34 ml/ml) against (4.76 and 26.03 ml/ml) for the HEC. These EO could thus be exploited as biodegradable antifungal substances, likely to control white rot of bean. 展开更多
关键词 s. sclerotiorum T. vulgaris C. Citratrus Essential Oils Antifungal activity INHIBITION
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Design of New Thiadiazole Derivatives with Improved Antidiabetic Activity
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作者 Chiépi Nadège Dominique Dou Georges Stéphane Dembele +5 位作者 Mamadou Guy-Richard Kone Nanou Tiéba Tuo Fandia Konate Adama Niare Panaghiotis Karamanis Nahossé Ziao 《Computational Chemistry》 2023年第3期67-80,共14页
Diabetes is a serious, long-term (or chronic) disease that occurs when a person’s blood sugar levels are high because their body cannot produce enough insulin, or does not produce enough insulin or that it cannot eff... Diabetes is a serious, long-term (or chronic) disease that occurs when a person’s blood sugar levels are high because their body cannot produce enough insulin, or does not produce enough insulin or that it cannot effectively use the insulin it produces. According to the literature, this disease has several causes, but certain types of diabetes such as type 2 diabetes are most closely linked to a metabolic disorder due to abdominal obesity. Thus, the number of individuals with type 2 diabetes is increasing. It is with this in mind that we work to improve human health. The aim of this study is to design new derivatives of 1,3,4-thiadiazole with improved antidiabetic activity by the mathematical model of multiple linear regression (MLR) established previously. The analysis of the effect on the substituents influencing the antidiabetic activity, fourteen (14) new molecules coded CDTH were generated and presenting values of the potential of inhibitory concentration higher than that of the base compound (pIC50 = 2.526). But thirteen (13) of these new compounds belong to the domain of applicability of the MLR model established previously. In addition, the thermodynamic quantities of formation formed at 298K have been calculated. Lipinski’s rule and pharmacokinetic properties proved that five (5) (TH4, TH9, TH10, TH13 and TH14) new molecules can be used as diabetes medicine. 展开更多
关键词 DEsIGN Antidiabetic activity 1 3 4-Thiadiazole Lipinski’s Rule
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S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3)的构筑及光催化还原CO_(2)性能 被引量:1
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作者 刘平 朱成才 +1 位作者 李艳阳 要红昌 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期197-208,共12页
通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽... 通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽进行光催化反应。优化后的材料光照5 h后CO_(2)还原产物CO和CH_(4)的产量分别为7.87和4.88μmol·g^(-1)。相对于单相组分,CO和CH_(4)的产量明显提高。光催化活性的提高,归因于ZnFe_(2)O_(4)和WO_(3)异质结的形成以及光生载流子的S型电荷传输模式。 展开更多
关键词 CO_(2)还原 光催化活性 ZnFe_(2)O_(4)/WO_(3) 异质结 s型电荷传输模式
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Preparation, Characterization, Photocatalytic Activity of S and Ag co-Doped Mesoporous Titania Photocatalysts
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作者 姚淑华 郑志慧 +1 位作者 陈爽 石中亮 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第6期732-738,I0004,共8页
In order to improve the photocatalytic performance of mesoporous titania under visible light, a series of photocatalysts of S and Ag co-doped mesoporous titania have been successfully prepared by template method using... In order to improve the photocatalytic performance of mesoporous titania under visible light, a series of photocatalysts of S and Ag co-doped mesoporous titania have been successfully prepared by template method using thiourea, AgNO3 and tetrabutyl titanate as precursors and Pluronic P123 (EO20PO70EO20) as template. Scanning electron microscopy (SEM), X-ray diffraction (XRD), nitrogen adsorption-desorption measurements, and UV-visible spectroscopy (UV-Vis) were employed to characterize the morphology, crystal structure, surface structure, and optical absorption properties of the samples. The microcrystal of the photocatalysts consisted of anatase phase and was approximately present in the form of spherical particle. The photocatalytic performance was studied by photodegradation methyl orange (MO) in water under UV and visible light irradiation. The calcination temperature and the doping content influenced the photoactivity. In addition, the possibility of cyclic usage of co-doped mesoporous titania was also confirmed, the photocatalytic activity of mesoporous titania remained above 89% of that of the fresh sample after being used four times. It was shown that the co-doped mesoporous titania could be activated by visible light and could thus be potentially applied for the treatment of water contaminated by organic pollutants. The synergistic effect of sulfur and silver co-doping played an important role in improving the photocatalytic activity. 展开更多
关键词 Mesoporous titania s and Ag co-doping Doped catalyst Photocatalytic activity Template method Dye decomposition
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Antibacterial Activity of Sophora flavescens Extracts against Pepper Blight (Fusarium oxysporum)
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作者 郑玉艳 《Plant Diseases and Pests》 CAS 2011年第3期59-61,共3页
[ Objectlve] The paper was to explore the antibacterial activity of S. fiavescens extracts against pepper blight. [ Methods] Growth rate method and sus- pend-drop method were used to measure the inhibition effect of d... [ Objectlve] The paper was to explore the antibacterial activity of S. fiavescens extracts against pepper blight. [ Methods] Growth rate method and sus- pend-drop method were used to measure the inhibition effect of different solvents and concentrations of S. fiavescens extracts on F. oxysporum. [Result] The inhibi- tion rate of etude extracts of S. flavescens extracted by ethyl acetate and acetone was significantly higher than that of ethanol. With the increasing concentration of ethyl acetate crude extracts of S. flavescens, its inhibition effect against myeelial growth and spore germination of F. oxysporum signitieantly increased. When the mass concentration was 40 g/L, its inhibition rates against myeelial growth and spore germination of F. oxysporum were 94.48% and 89.01%, respectively. [ Con- clusion] The active substance contained in S. flavescens roots had strong inhibition activity against pepper blight, which had the potential value for further research and development. 展开更多
关键词 s. flavescens Pepper blight Antlbacterial activity China
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车辆主动悬架自适应变论域T-S模糊控制研究
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作者 李韶华 季广港 +1 位作者 冯桂珍 王贺 《振动.测试与诊断》 EI CSCD 北大核心 2024年第4期733-739,828,共8页
针对传统变论域模糊控制存在过度依赖专家经验、伸缩因子参数不能自适应调整的问题,提出一种车辆主动悬架自适应变论域T-S模糊控制策略,从而提高车辆的行驶平顺性。结合神经网络和T-S模糊推理建立基于自适应神经模糊推理的一阶T-S模糊... 针对传统变论域模糊控制存在过度依赖专家经验、伸缩因子参数不能自适应调整的问题,提出一种车辆主动悬架自适应变论域T-S模糊控制策略,从而提高车辆的行驶平顺性。结合神经网络和T-S模糊推理建立基于自适应神经模糊推理的一阶T-S模糊控制器,利用神经网络的自学习特性产生完善的模糊规则,进而在传统函数型伸缩因子的基础上,将系统误差和误差变化率作为动态参数引入伸缩因子中,实现伸缩因子参数的自适应调整,解决了传统函数型伸缩因子因参数确定难度大导致控制效果差的问题。通过随机工况下的仿真分析和基于相似理论的缩尺实验,对所提出算法的有效性和工况自适应性进行了验证。结果表明,所提出的自适应变论域T-S模糊控制策略具有较强的工况适应性,在不同车速、路面激励下均可有效提高车辆的平顺性并保证轮胎接地安全性。 展开更多
关键词 主动悬架 变论域 伸缩因子 T-s模糊控制 神经模糊系统
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基于UHPLC-Q-Orbitrap HRMS雀嘴茶醇提液的成分及活性研究 被引量:1
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作者 王文博 袁甜甜 +6 位作者 吕玉秀 刘桢 谢东 张璟雯 赵平 陈保森 杨晓琴 《西南林业大学学报(自然科学)》 CAS 北大核心 2024年第1期176-184,共9页
基于超高效液相色谱串联四级杆/静电场轨道阱高分辨质谱快速分析雀嘴茶醇提液的成分,对其体外抗氧化活性和酪氨酸酶抑制活性进行研究。结果表明:从雀嘴茶醇提液中鉴定出1 321个代谢物,其中有1 085个代谢物包括11个超类匹配到人类代谢数... 基于超高效液相色谱串联四级杆/静电场轨道阱高分辨质谱快速分析雀嘴茶醇提液的成分,对其体外抗氧化活性和酪氨酸酶抑制活性进行研究。结果表明:从雀嘴茶醇提液中鉴定出1 321个代谢物,其中有1 085个代谢物包括11个超类匹配到人类代谢数据库中,含量较高的活性代谢物,包括新甘草苷、扁蓄苷、醋硝香豆素、槲皮素-3-O-葡萄糖苷桂皮鞣质B1等苯丙素类和芳香聚酮类、咖啡因等有机杂环化合物类、阿糖腺苷等核苷酸及其衍生物以及1-咖啡酰-β-D-葡萄糖、3-O-阿魏酰奎尼酸、绿原酸、2-O-咖啡酰熊果苷等咖啡酰类。雀嘴茶醇提液的DPPH·清除率可达93.56%,ABTS^(+)·清除率可达99.04%,OH·清除率可达94.82%,总还原能力随着醇提液中总多酚浓度的增加而升高且效果极为接近阳性对照抗坏血酸;对酪氨酸酶单酚酶和二酚酶的抑制率分别可达81.50%和58.58%。 展开更多
关键词 雀嘴茶 醇提液 静电场轨道阱高分辨质谱 抗氧化 酪氨酸酶 活性代谢物
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Synthesis and antibacterial activity of C-2(S)-substituted pleuromutilin derivatives 被引量:5
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作者 Li Qiang Fu Xing Sheng Guo +3 位作者 Xin Liu Hui Li He Yu Ling Wang Yu She Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第5期507-510,共4页
In order to probe the effect of C-2(S)-substituted groups in the antibacterial activity,a series of novel C-2(S)-substituted pleuromutilin analogues of SB-225586 were synthesized and evaluated for their in vitro antib... In order to probe the effect of C-2(S)-substituted groups in the antibacterial activity,a series of novel C-2(S)-substituted pleuromutilin analogues of SB-225586 were synthesized and evaluated for their in vitro antibacterial activity.The results of antibacterial activities indicated that C-2(S)-substituted pleuromutilin derivatives retained appreciable antibacterial activity,and the 2-fluorination compounds 6a and 6b are more potent than the corresponding 2-hydroxylation analogues 7a and 7b. 展开更多
关键词 sYNTHEsIs Pleuromutilin C-2(s)-substituted Antimicrobial activity
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