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411篇 您的检索式:作者名="Suresh Kumar"
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1Risk factors for ventilator-associated pneumonia in trauma patients:A descriptive analysis显示文摘BACKGROUND:We sought to evaluate the risk factors for developing ventilator-associated pneumonia(VAP)and whether the location of intubation posed a risk in trauma patients.METHODS:Data were retrospectively reviewed for adult trauma patients requiring intubation for>48 hours,admitted between 2010 and 2013.Patients’demographics,clinical presentations and outcomes were compared according to intubation location(prehospital intubation[PHI]vs.trauma room[TRI])and presence vs.absence of VAP.Multivariate regression analysis was performed to identify predictors of VAP.RESULTS:Of 471 intubated patients,332 patients met the inclusion criteria(124 had PHI and208 had TRI)with a mean age of 30.7±14.8 years.PHI group had lower GCS(P=0.001),respiratory rate(P=0.001),and higher frequency of head(P=0.02)and chest injuries(P=0.04).The rate of VAP in PHI group was comparable to the TRI group(P=0.60).Patients who developed VAP were 6 years older,had significantly lower GCS and higher ISS,head AIS,and higher rates of polytrauma.The overall mortality was 7.5%,and was not associated with intubation location or pneumonia rates.In the early-VAP group,gram-positive pathogens were more common,while gram-negative microorganisms were more frequently encountered in the late VAP group.Logistic regression analysis and modeling showed that the impact of the location of intubation in predicting the risk of VAP appeared only when chest injury was included in the models.CONCLUSION:In trauma,the risk of developing VAP is multifactorial.However,the location of intubation and presence of chest injury could play an important role.Suresh Kumar Arumugam Insolvisagan Mudali Gustav Strandvik Ayman El-Menyar Ammar Al-Hassani Hassan Al-Thani1 2018World Journal of Emergency Medicine2018,9,3:17
2海枣核CO_2活化和磷酸活化制备活性炭及其结构、吸附性能(英文)显示文摘由于具有很大的吸附容量,多孔炭材料是优良的吸附剂。笔者试图比较海枣核分别经CO2活化和磷酸活化所制活性炭的结构和吸附性能。活化过程和工艺条件对炭的物理化学性质影响较大,根据文献报道的结果选取了优化的工艺参数。基于氮气吸附等温线、SEM、FT-IR等分析结果,评估了活性炭的结构特征,吸附性能则由亚甲蓝吸附值表示。CO2活化得到了微孔活性炭,产率为44%、BET比表面积是666 m2·g-1;磷酸活化得到了产率为14.8%的中孔活性炭,BET比表面积为725 m2·g-1。CO2活化活性炭的平均孔径是1.51 nm,磷酸活化活性炭的则为2.91 nm。活性炭的亚甲蓝吸附等温线分别用Langmuir等温线和Freundlich等温线进行了验证,在优化工艺条件下制备的CO2活化炭和磷酸活化炭的亚甲蓝w单分子吸附容量分别为110 mg·g-1和345 mg·g-1。然而,磷酸活化产生的亚甲蓝吸附值最高达455 mg·g-1。K. Suresh Kumar Reddy Ahmed Al Shoaibi C. Srinivasakannan 2012新型炭材料2012,27,5:14
3Hybrid, Optimal, Intelligent and Classical PV MPPT Techniques: A Review显示文摘Renewable energy-based solar photovoltaic(PV)generation is the best alternative for conventional energy sources because of its natural abundance and environment friendly characteristics.Maximum power extraction from the PV system plays a critical role in increasing the efficiency of the solar power generation during partial shading conditions(PSCs).Therefore,a suitable maximum power point tracking(MPPT)technique to track the maximum power point(MPP)is of high need,even under PSCs.This paper presents an organized and concise review of MPPT techniques implemented for the PV systems in literature along with recent publications on various hardware design methodologies.Their classification is done into four categories,i.e.classical,intelligent,optimal,and hybrid depending on the tracking algorithm utilized to track MPP under PSCs.During uniform insolation,classical methods are highly preferred as there is only one peak in the P-V curve.However,under PSCs,the F-V curve exhibits multiple peaks,one global maximum power point(GMPP)and remaining are local maximum power points(LMPP’s).Under the PSCs,classical methods fail to operate at GMPP and hence there is a need for more advanced MPPT techniques.Every MPPT technique has its advantages and limits,but a streamlined MPPT is drafted in numerous parameters like sensors required,hardware implementation,cost viability,tracking speed and tracking efficiency.This study provides the advancement in this area since some parameter comparison is made at the end of every classification,which might be a prominent base-rule for picking the most gainful sort of MPPT for further research.Ratnakar Babu Bollipo Suresh Mikkili Praveen Kumar Bonthagorla 2021CSEE Journal of Power and Energy Systems2021,7,1:10
4Characteristics of MOF, MWCNT and graphene containing materials for hydrogen storage: A review显示文摘Hydrogen is a generally abundant, safe, clean and environmentally apt alternative fuel, which replenishes the void generated by depleting fossil fuel reserves. The adoption of hydrogen as an energy source has been restricted to low levels due to the complications associated with its viable storage and usage. Existing technologies, such as storage of hydrogen in compressed and liquefied forms are not adequate to meet the broad on-board applications. The gravimetric energy density(120 MJ/kg) of hydrogen is three times higher than that of gasoline products, so solid-state hydrogen storage is advantageous.Metal-organic frameworks(MOFs), multi-walled carbon nanotubes(MWCNTs) and graphene are solid adsorbents majorly employed for efficient H_2 storage. The prominent features of MOFs such as permanent porosity, structural rigidity, and surface area are attractive and ideal for hydrogen storage. In addition,nanostructured carbon materials(MWCNTs and graphene) and their composites have demonstrated significant hydrogen storage capacities. Some important parameters for the success of the hydrogen economy include high storage density, adsorption/desorption temperature and cycling time. Cryo-hydrogen storage was achieved in MOFs and their composites with carbon structures, but storage at ambient temperature and acceptable pressures is a major hurdle. This review discusses various strategies and mechanisms in the design of adsorbents explored to improve H_2 storage capacities and afford opportunities to develop new sustainable hydrogen technologies to meet energy targets.Kranthi Kumar Gangu Suresh Maddila Saratchandra Babu Mukkamala Sreekantha B Jonnalagadda 2019Journal of Energy Chemistry2019,28,3:10
5Effect of desliming on the magnetic separation of low-grade ferruginous manganese ore显示文摘In the present investigation, magnetic separation studies using an induced roll magnetic separator were conducted to beneficiate low-grade ferruginous manganese ore. The feed ore was assayed to contain 22.4% Mn and 35.9% SiO 2, with a manganese-to-iron mass ratio(Mn:Fe ratio) of 1.6. This ore was characterized in detail using different techniques, including quantitative evaluation of minerals by scanning electron microscopy, which revealed that the ore is extremely siliceous in nature and that the associated gangue minerals are more or less evenly distributed in almost all of the size fractions in major proportion. Magnetic separation studies were conducted on both the as-received ore fines and the classified fines to enrich their manganese content and Mn:Fe ratio. The results indicated that the efficiency of separation for deslimed fines was better than that for the treated unclassified bulk sample. On the basis of these results, we proposed a process flow sheet for the beneficiation of low-grade manganese ore fines using a Floatex density separator as a pre-concentrator followed by two-stage magnetic separation. The overall recovery of manganese in the final product from the proposed flow sheet is 44.7% with an assay value of 45.8% and the Mn:Fe ratio of 3.1.Sunil Kumar Tripathy P.K.Banerjee Nikkam Suresh 2015International Journal of Minerals,Metallurgy and Materials2015,22,7:6
6Comparative investigation of coal-and oil-fired boilers based on emission factors,ozone and secondary organic aerosol formation potentials of VOCs显示文摘Volatile organic compounds(VOCs)are the important precursors of the tropospheric ozone(O3)and secondary organic aerosols(SOA),both of which are known to harm human health and disrupt the earth’s climate system.In this study,VOC emission factors,O3 and SOA formation potentials were estimated for two types of industrial boilers:coal-fired boilers(n=3)and oil-fired boilers(n=3).Results showed that EVOCs concentrations were more than nine times higher for oil-fire d boilers compared to those for coal-fired boilers.Emission factors ofΣVOCs were found to be higher for oil-fired boilers(9.26-32.83 mg-VOC/kg)than for coal-fired boilers(1.57-4.13 mg-VOC/kg).Alkanes and aromatics were obtained as the most abundant groups in coal-fired boilers,while oxygenated organics and aromatics were the most contributing groups in oil-fired boilers.Benzene,n-hexane and o-ethyl toluene were the abundant VOC species in coal-fired boiler emissions,whereas toluene was the most abundant VOC species emitted from oil-fired boilers.O3 and SOA formation potentials were found 12 and 18 times,respectively,higher for oil-fired than for coal-fired boilers.Total OFP ranged from 3.99 to 11.39 mg-O3/kg for coal-fired boilers.For oil-fired boilers,total OFP ranged from 36.16 to 131.93 mg-O3/kg.Moreover,total secondary organic aerosol potential(SOAP)ranged from 65.4 to 122.5 mg-SOA/kg and 779.9 to 2252.5 mg-SOA/kg for the coal-fired and oil-fired boilers,respectively.Hsi-Hsien Yang Sunil Kumar Gupta Narayan Babu Dhital Lin-Chi Wang Suresh Pandian Elumalai 2020Journal of Environmental Sciences2020,32,6:6
7Anti-microbial principles of selected remedial plants from Southern India显示文摘Objective:To examine the anti-bacterial activity of leaf extracts of Morus alba L.(Moraceae)and Piper betel L.(Piperaceae),and seed extracts of Bombax ceiba L.(Borabacaceae).Methods:We have partially purified plant extracts by solvent extraction method,and evaluated the effect of individual fractions on bacterial growth using Escherichia coli(E.coli),Pseudomonas aeruginosa(P.aeruginosa) and Staphylococcus aureus(S.aureus) bacterial strains.Results:Compared with Morus and Bombax fractions,Piper fractions showed significant growth inhibition on all the three types of bacteria studied.The EtOAc-hexane fractions of Piper leaves exhibited significant antibacterial activity with minimum inhibitory concentrations(MIC) of 50 μg/mL culture against both gram-positive and gram-negative bacteria.The EtOAc-fractions Ⅰ,Ⅱ,and Ⅳ inhibited bacterial colony formation on soft agar in addition to growth inhibition.A combination treatment of piper fractions with ampicillin resulted in significant growth inhibition in E.coli and P.aeruginosa,and combination with anticancer drug geldanamycin(2 μg/mL) showed selective growth inhibition against P.aeruginosa and S.aureus.Three major compounds,i.e.,eugenol,3-hexene-ol and stigmasterol,were primarily identified from Piper betel leaf extractions.Among the individual compounds,eugenol treatment showed improved growth inhibition compared with stigmasterol and 3-hexene-ol.Conclusions:We are reporting potential anti-bacterial compounds from Piper betel against both gram-positive and gram-negative bacteria either alone or in combination with drug treatment.Tirupathi Rao G Suresh Babu K J Ujwal Kumar Sujana P A Veerabhadr Raoa Sreedhar AS 2011Asian Pacific Journal of Tropical Biomedicine2011,1,4:5
8Predicting the impact of climate change on the distribution of two threatened Himalayan medicinal plants of Liliaceae in Nepal显示文摘Predicting the potential distribution of medicinal plants in response to climate change is essential for their conservation and management. Contributing to the management program, this study aimed to predict the distribution of two threatened medicinal plants, Fritillaria cirrhosa and Lilium nepalense. The location of focal species gathered from herbarium specimen housed in different herbaria and online databases were geo-referenced and checked for spatial autocorrelation. The predictive environmental variables were selected, and MaxE nt software was used to model the current and future distributions of focal species. Four Representative Concentration Pathway(RCP) trajectories of the BCC-CSM1.1 model were used as the future(2050) projection layer. The MaxEnt modelling delineated the potential distribution of F. cirrhosa and L. nepalense. The current suitability is projected towards Central and Eastern Hilly/Mountainous regions. Both species gainmaximum suitability in RCP 4.5 which decline towards other trajectories for L. nepalense. Overall, both the focal species shift towards the north-west, losing their potential habitat in hilly and lower mountainous regions by 2050 across all trajectories. Our results highlight the impact of future climate change on two threatened and valuable species. The results can be further useful to initiate farming of these medicinally and economically important species based on climatically suitable zone and for designing a germplasm conservation strategy.RANA Santosh Kumar RANA Hum Kala GHIMIRE Suresh Kulllar SHRESTHA Krishna Kumar RANJITKAR Sailesh 2017Journal of Mountain Science2017,14,3:5
9Metathesis synthesis, characterization, spectral and photoactivity studies of Ln_(2/3)MoO_4(Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er and Y)显示文摘Rare earth ortho-oxomolybdates of composition Ln2/3MoO 4(Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er and Y) were prepared by metathesis reaction. All these materials were characterized by powder X-ray diffraction, Fourier transform-infrared spectroscopy(FT-IR) and UV-Vis diffuse reflectance spectra. The Rietveld analysis of all the samples was carried out to obtain the unit cell parameters and reliability factors. All the materials were crystallized in tetragonal lattice with I41/a space group. The infrared spectra of all the samples were characterized by bands due to MoO 2–4 units. The bandgap energies of all the samples were obtained from UV-Vis DRS spectra. The luminescence spectra of Ln2/3MoO 4(Ln=Pr, Eu and Dy) showed characteristic transitions of the rare earth ions. The visible light photocatalytic activity of all the samples was studied against degradation of methylene blue.Radha Velchuri Suresh Palla G.Ravi Naveen Kumar Veldurthi J.R.Reddy M.Vithal 2015Journal of Rare Earths2015,33,8:5
10纳米钯催化苄基氯代物与烯丙基硼酸频哪醇酯的羧化Suzuki偶联反应(英文)显示文摘CO_2是廉价的Cl源,同时具有无毒、储量丰富的优点,符合绿色化学发展要求.利用CO_2构筑新的C-C键是化学固定CO_2的重要方法.β,γ-不饱和酯类结构单元是许多生物活性分子的重要组成部分,经由双π-烯丙基钯中间体与CO_2反应,合成新的β,γ-不饱和酯类化合物,具有重要意义.CO_2与有机硼化合物的羧化反应己有报道,有机硼化合物具有低毒、对水不敏感等优点.但是己报道的羧化Suzuki偶联反应存在诸多缺点:(1)需要使用含膦或者氮杂环卡宾配体的催化剂,而这些催化剂的制备过程使前期实验步骤变得冗长,同时反应液的酸化后处理过程也会造成环境污染;(2)有机硼试剂的官能团兼容范围窄,限制了底物范围的拓展.本课题组以原位生成的纳米钯粒子为催化剂,在CO_2存在的温和条件下,高效实现了苄氯与烯丙基硼酸频哪醇酯的羧化Suzuki偶联反应.反应过程中无其它配体加入,反应结束后不需要酸化或酯化的后处理过程.该反应将具有广泛的官能团兼容性.本文以TBAB稳定的纳米钯粒子为催化剂,在温和条件下,实现了氯甲基芳香化合物、烯丙基硼酸频哪醇酯和CO_2的三组分羧化Suzuki偶联反应.最佳反应条件为:Pd(acac)_2(5mol%)、TBAB(0.7mmol,1.4 equiv.)、KF(1mmol,2.0 equiv.)、苄基卤代物(0.5 mmol)、烯丙基硼酸频哪醇酯(0.6 mmol,1.2 equiv.)、CO_2(2.0 MPa)、溶剂THF(5 mL),50℃反应24h.在最佳反应条件下,苯环、萘环以及杂芳环的氯甲基化合物均可发生该羧化反应.苯环上取代基的位置对产物的收率有影响.当使用1-溴甲基萘作为底物时反应也能够发生,收率与1-氯甲基萘作为底物时的收率相当.与已报道有机硼试剂的羧化反应相比,该反应体系无需加入配体,原位生成了纳米钯粒子,避免了催化剂或者配体的复杂制备过程.该反应中,氟离子的存在是必要的,对烯丙基硼酸频哪醇酯具有活化作用.孙健 王加升 冯秀娟 Yoshinori Yamamoto Abdulrahman I.Almansour Natarajan Arumugam Raju Suresh Kumar 包明 2018Chinese Journal of Catalysis2018,39,7:4
11Prospects to the formation and control of potential dimer impurity E of pantoprazole sodium sesquihydrate显示文摘Pantoprazole sodium, a substituted benzimidazole derivative, is an irreversible proton pump inhibitor which is primarily used for the treatment of duodenal ulcers, gastric ulcers, and gastroesophageal reflux disease (GERD). The monographs of European Pharmacopoeia (Ph. Eur.) and United States Pharmacopoeia (USP) specify six impurities, viz.;impurities A, B, C, D, E and F, respectively for its active pharmaceutical ingredient (API). The identification and synthesis of all impurities except impurity E are well described in the literature;however, there is no report related to impurity E. The prospects to the formation and controlling of impurity E up to -0.03% in the synthesis of pantoprazole sodium sesquihydrate (PAN) were discussed in detail for the first time. The present work described the journey towards the successful development of an optimal preparation procedure of dimer impurity E. The most plausible mechanism involved in the formation of impurity E has been proposed.Arun Kumar Awasthi Lalit Kumar Punit Tripathi Madhava Golla Cirandur Suresh Reddy Pramod Kumar 2019Journal of Pharmaceutical Analysis2019,9,3:4
12Colorectal cancer screening in human immunodeficiency virus population:Are they at average risk?显示文摘AIM:To evaluate if human immunodeficiency virus (HIV) population is getting adequate screening for colon cancer in the highly active anti-retroviral treatment (HAART) era with improved longevity, and the prevalence of polyps and adenomas in this population, when compared with the general population. METHODS:We conducted retrospective chart review of average-risk HIV population for colon cancer attending our infectious disease clinic. Individuals who underwent diagnostic colonoscopy were excluded. We extracted various demographic, HIV disease-specific and colonoscopy data including histo-pathological reports in the last 10 years. Total population was divided into a study group, who underwent screening colonoscopy and a control group who did not. We analyzed data using standard statistical methods and software. RESULTS:We found that 25% of average-risk HIVinfected population was screened for colon cancer using colonoscopy. There was no difference in gender and ethnic distribution between the groups. We foundwider distribution of age (50-84 years with mean 56 years) in the control group when compared to (50-73 years with mean 58 years) the study group. However, there were 89% of subjects with well-controlled HIV disease measured by HIV RNA copies of < 75 in the study group when compared with 70% in the control group (P < 0.0001). We noticed polyp detection rate of 55% and adenoma detection rate of 32% in HIV population. CONCLUSION:It is unclear whether HIV or HAART medications play a role in increased prevalence of adenomas. We suggest that when estimating the risk for colonic neoplasms, HIV population should be considered as a high-risk group and screened accordingly.Suresh Kumar Nayudu Bhavna Balar 2012World Journal of Gastrointestinal Oncology2012,4,12:3
13Analysis of Carbaryl Pesticide Residues in Environmental Samples with Spectrophotometry显示文摘一个灵巧、快速、敏感的 spectrophotometric 方法在它的明确的表达,水和谷物(米饭和小麦) 为酉维因的决心被开发样品与最新 synthesised 试剂。建议方法基于杀虫剂和因此结果的1萘粉是的酉维因的碱的水解作用在基本媒介结合了 diazotised 4,4-methylene-bis-m-nitroaniline ( pH 9 )为重氮基方法( DM )或1萘粉的 480 nm 面对 oxidising 与 4,4-methylene-bis-m-nitroaniline 反应给红有颜色的产品有最大代理人钾重铬酸盐( K2Cr2O7 )给为氧化方法( OM )有最大 510 nm 的产品涂颜色给红。有联合代理人的有颜色的衍生物的形成分别地为 48 h (DM ) 和 32 h (OM ) 即时、稳定。啤酒的法律 gpectively 在 0.210.0 的集中范围被遵守。另外,第一件汗衫(n, *) 单体的垂直刺激精力和氢在磺安剂和水之间的结合的建筑群被 time-dep 躨?躨 调查??REKHA, Dasari SUVARDHAN, Kanchi KUMAR, Kailasa Suresh JAYARAJ, Bellum CHIRANJEEVI, Pattium 2006Chinese Journal of Chemistry2006,24,8:3
14Risk factors for the development of colorectal carcinoma:A case control study from South India显示文摘AIM:To study the association of colorectal carcinoma(CRC) with diet,smoking,alcohol,physical activity,body mass index,family history and diabetes.METHODS: All consecutive patients with CRC confirmed by histopathology diagnosis were included. Age(±5 years) and gender matched controls were selected among the patients admitted in surgery ward for various conditions without any co-existing malignancy. Food frequency questionnaire(FFQ) was developed and validated after pretesting by investigator trained in data col ection techniques. Cases and controls were interviewed ensuring privacy,in similar interview setting,with same duration of time for both cases and controls without any leading question. Biological variables like family history of CRC in first degree relatives,history of diabetes mellitus; behavioral factors like tobacco use both smoking and smokeless form,alcohol consumption and physical activity were recorded. Dietary details were recorded using a FFQ consisting 29 food items with seven categories. Analysis was done using appropriate statistical methods.RESULTS: Ninety-four histopathologically confirmed cases of CRC and equal number of age and gender matched controls treated over a period of two years were studied. Age distribution,mean age,male to female ratio,education level and socioeconomic status were similar in cases and controls. Intake of food items was categorized into tertile due to skewed distribution of subjects as per recommended cut off for consumption of food item. On univariate analysis red meat [OR=7.4(2.935-18.732)],egg [OR=5.1(2.26-11.36)],fish,fried food and oil consumption were found to be risk factors for CRC. On multivariate analysis red meat consumption of more than 2-3 times a month(OR=5.4; 95%CI:1.55-19.05) and egg consumption of more than 2-3 times a week(OR = 3.67; 95%CI:1.23-9.35) were found to be independent risk factors for the development of CRC.CONCLUSION: Egg and red meat consumption found to be independent risk factors for CRC. Smoking,alcohol,physical activity and family history were not associated with increased risk.Santhana Krishnan Iswarya Kariyarath Cheriyath Premarajan Sitanshu Sekhar Kar Sathasivam Suresh Kumar Vikram Kate 2016World Journal of Gastrointestinal Oncology2016,8,2:3
15Investigation of Structural, Rheological and Thermal Properties of PMMA/ONi-Al LDH Nanocomposites Synthesized via Solvent Blending Method: Effect of LDH Loading显示文摘This article addresses the synthesis of organically tailored Ni-Al layered double hydroxide(ONi-Al LDH) and its use in the fabrication of exfoliated poly(methyl methacrylate)(PMMA) nanocomposites. The pristine Ni-Al LDH was initially synthesized by co-precipitation method and subsequently modified using sodium dodecyl sulfate to obtain ONi-Al LDH. Nanocomposites of PMMA containing various amounts of modified Ni-Al LDH(3 wt%?7 wt%) were synthesized via solvent blending method to investigate the influence of LDH content on the properties of PMMA matrix. Several characterization methods such as X-ray diffraction(XRD), transmission electron microscopy(TEM), Fourier transform infrared spectroscopy(FTIR), rheological analysis, differential scanning calorimetry(DSC) and thermo gravimetric analysis(TGA), were employed to examine the structural, viscoelastic and thermal properties of PMMA/OLDH nanocomposites. The results of XRD and TEM examination confirm the formation of partially exfoliated PMMA/OLDH nanocomposites. The FTIR results elucidate that the characteristic bands for both pure PMMA and modified LDH are present in the spectra of PMMA/OLDH nanocomposites. Rheological analyses were carried out to examine the adhesion between polymer matrix and fillers present in the nanocomposite sample. The TGA data indicate that the PMMA nanocomposites exhibit higher thermal stability when compared to pure PMMA. The thermal decomposition temperature of PMMA/OLDH nanocomposites increases by 28 K compared to that of pure PMMA at 15% weight loss as a point of reference. In comparison with pure PMMA, the PMMA nanocomposite containing 7 wt% LDH demonstrates improved glass transition temperature(Tg) of around 3 K. The activation energy(Ea), reaction orders(n) and reaction mechanism of thermal degradation of PMMA/OLDH nanocomposites were evaluated using different kinetic models. Water uptake capacity of the PMMA/OLDH nanocomposites is less than that of the pure PMMA.Samarshi Chakraborty Manish Kumar Kelothu Suresh G.Pugazhenthi 2016Chinese Journal of Polymer Science2016,34,6:3
16生姜提取物6-姜酚对对乙酰氨基酚致小鼠肝脏毒性的保护作用(英文)显示文摘目的:研究生姜提取物6-姜酚对对乙酰氨基酚致小鼠肝脏毒性的保护作用。方法:实验组小鼠在腹腔注射对乙酰氨基酚(900 mg/kg)30 min后,分别给予6-姜酚(30 mg/kg)或标准对照药水飞蓟素(25 mg/kg)。注射对乙酰氨基酚4 h后处死小鼠,检测血清中天冬氨酸氨基转移酶、丙氨酸氨基转移酶、碱性磷酸酶活性,总胆红素的含量及肝匀浆中脂质过氧化及抗氧化情况,如超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶、谷胱甘肽还原酶、谷胱甘肽转移酶活性及还原型谷胱甘肽含量。结果:与对照组相比,6-姜酚及水飞蓟素均能显著降低对乙酰氨基酚引起的小鼠血清天冬氨酸氨基转移酶、丙氨酸氨基转移酶、碱性磷酸酶活性及总胆红素含量的升高(P<0.05)。此外,6-姜酚及水飞蓟素有效控制了肝脏内丙二醛的形成及各种抗氧化酶的降低(P<0.05)。结论:本研究的结果证实了6-姜酚具有与水飞蓟素相当的保肝作用。Evan Prince Sabina Samuel Joshua Pragasam Suresh Kumar Mahaboobkhan Rasool 2011中西医结合学报2011,9,11:3
17Characteristics of La-modified Ni-Al_2O_3 and Ni-SiO_2 catalysts for CO_x-free hydrogen production by catalytic decomposition of methane显示文摘Hydrotalcite precursors of La modified Ni-Al2O3 and Ni-SiO2 catalysts prepared by co-precipitation method and the catalytic activities were examined for the production of COx-free H2 by CH4 decomposition. Physico-chemical characteristics of fresh, reduced and used catalysts were evaluated by XRD, TPR and O2 pulse chemisorptions, TEM and BET-SA techniques. XRD studies showed phases due to hydrotalcite-like precursors in oven dried form produced dispersed NiO species upon calcination in static air above 450 C. Raman spectra of deactivated samples revealed the presence of both ordered and disordered forms of carbon. Ni-La-Al2O3catalyst with a mole ratio of Ni : La : Al = 2 : 0.1 : 0.9 exhibited tremendously high longevity with a hydrogen production rate of 1300 molH2 mol 1 Ni. A direct relationship between Ni metal surface area and hydrogen yields was established.Chatla Anjaneyulu Velisoju Vijay Kumar Suresh K.Bhargava Akula Venugopal 2013Journal of Energy Chemistry2013,22,6:2
18非负载纳米多孔钯催化喹啉及其衍生物的化学选择性氢化反应:H_2分子异裂(英文)显示文摘纳米多孔金属是近十年发展起来的一类具有三维通孔结构的新型功能材料,其由纳米尺度的细孔和韧带构成,具有极大的比表面积;它还是一种无毒无载体的宏观材料,并且易制备、易回收和重复利用,因此作为高效的非均相催化剂已逐渐引起人们的重视.1,2,3,4-四氢喹啉是许多医药、农药、染料和天然产物的重要骨架.通过喹啉及其衍生物的选择性加氢反应制备1,2,3,4-四氢喹啉,具有原子利用率高和原料易得等优点.在过去,已经开发了许多类型的均相和非均相催化体系,并成功地用于催化喹啉及其衍生物的选择性加氢反应.尽管非均相催化体系具有诸多优点,但仍存在H_2压力(10–50 atm)和反应温度(60–150℃)相对较高的缺点.因此,开发更加温和条件下的喹啉及其衍生物的选择性加氢反应具有重要意义.此外,在喹啉及其衍生物的加氢反应过程中,H_2分子在非均相催化剂表面的裂解模式,即均裂还是异裂尚不清楚.因此,本文采用新型非均相催化剂纳米多孔钯,研究了喹啉及其衍生物的选择性加氢反应,在相对较低的H_2压力(2–5 atm)和温度(室温–50℃)下实现了目标反应,高收率、高选择性地得到1,2,3,4-四氢喹啉化合物.在最佳反应条件下,对底物的适用范围进行了考察.结果表明,各种含喹啉结构单元的化合物均能顺利发生反应,产物收率在62%–95%.而且该反应对甲基、甲氧基、羟基、酯基、醛基、酰胺基、卤素(F,Cl和Br)等官能团具有较好的兼容性.苯环上取代基的电子效应对反应有一定的影响,吸电子基有利于目标反应的进行.反应完成后,纳米多孔钯催化剂很容易回收,且循环使用多次后,仍未见催化活性降低.扫描电镜和透射电镜结果发现,循环使用后的纳米多孔钯催化剂结构没有发生明显改变,表明其结构稳定.浸出实验结果证明,没有钯原子浸出到反应液中,表明该纳米多孔钯催化反应属于多相催化过程.喹啉的选择性氢化反应被放大到克级的规模时,目标产物的收率仅略有降低,说明该方法具有很好的实用性.通过动力学实验发现,随着反应的进行,反应速率不断加快,表明反应过程中生成的乙胺和1,2,3,4-四氢喹啉同样扮演着路易斯碱性添加剂的角色,促进了反应的进行.通过反应机理研究,揭示了H–H键在纳米多孔钯表面发生了异裂,原位形成的Pd–H物种作为弱亲核试剂,对目标反应的选择性控制起到了至关重要的作用.卢烨 Yoshinori Yamamoto Abdulrahman I.Almansour Natarajan Arumugam Raju Suresh Kumar 包明 2018Chinese Journal of Catalysis2018,39,11:2
19Prevalence of advanced liver fibrosis and steatosis in type-2 diabetics with normal transaminases:A prospective cohort study显示文摘BACKGROUND Nonalcoholic fatty liver disease(NAFLD)and type-2 diabetes mellitus(T2DM)have an intricate bidirectional relationship.Individuals with T2DM,not only have a higher prevalence of non-alcoholic steatosis,but also carry a higher risk of progression to nonalcoholic steatohepatitis.Experts still differ in their recommendations of screening for NAFLD among patients with T2DM.AIM To study the prevalence of NAFLD and advanced fibrosis among our patient population with T2DM.METHODS During the study period(November 2018 to January 2020),59 adult patients with T2DM and 26 non-diabetic control group individuals were recruited prospectively.Patients with known significant liver disease and alcohol use were excluded.Demographic data and lab parameters were recorded.Liver elastography was performed in all patients.RESULTS In the study group comprised of patients with T2DM and normal alanine aminotransferase levels(mean 17.8±7 U/L),81%had hepatic steatosis as diagnosed by elastography.Advanced hepatic fibrosis(stage F3 or F4)was present in 12%of patients with T2DM as compared to none in the control group.Patients with T2DM also had higher number of individuals with grade 3 steatosis[45.8%vs 11.5%,(P<0.00001)and metabolic syndrome(84.7%vs 11.5%,P<0.00001)].CONCLUSION A significant number of patients with T2DM,despite having normal transaminase levels,have NAFLD,grade 3 steatosis and advanced hepatic fibrosis as measured by liver elastography.Jasbir Makker Hassan Tariq Kishore Kumar Madhavi Ravi Danial Haris Shaikh Vivien Leung Umar Hayat Muhammad T Hassan Harish Patel Suresh Nayudu Sridhar Chilimuri 2021World Journal of Gastroenterology2021,27,6:2
20Studies on the Functional Properties of Protein Concentrate of Kappaphycus alvarezii (Doty) Doty – An Edible Seaweed显示文摘K. Suresh Kumar K. Ganesan Kandasamy Selvaraj P.V. Subba Rao 2013Food Chemistry2013,,:2
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