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83篇 您的检索式:作者名="Muhammad Imran Khan"
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1Crosstalk of liver immune cells and cell death mechanisms in different murine models of liver injury and its clinical relevance显示文摘BACKGROUND: Liver inflammation or hepatitis is a result of pluripotent interactions of cell death molecules, cytokines, chemokines and the resident immune cells collectively called as microenvironment. The interplay of these inflammatory mediators and switching of immune responses during hepatotoxic, viral, drug-induced and immune cell-mediated hepatitis decide the fate of liver pathology. The present review aimed to describe the mechanisms of liver injury, its relevance to human liver pathology and insights for the future therapeutic interventions.DATA SOURCES: The data of mouse hepatic models and relevant human liver diseases presented in this review are systematically collected from Pub Med, Science Direct and the Web of Science databases published in English. RESULTS: The hepatotoxic liver injury in mice induced by the metabolites of CCl4, acetaminophen or alcohol represent necrotic cell death with activation of cytochrome pathway, formation of reactive oxygen species(ROS) and mitochondrial damage. The Fas or TNF-α induced apoptotic liver injury was dependent on activation of caspases, release of cytochrome c and apoptosome formation. The Con A-hepatitis demonstrated the involvement of TRAIL-dependent necrotic/necroptotic cell death with activation of RIPK1/3. The α-Gal Cer-induced liver injury was mediated by TNF-α. The LPS-induced hepatitis involved TNF-α, Fas/Fas L, and perforin/granzyme cell death pathways. The MHV3 or Poly(I:C) induced liver injury was mediated by natural killer cells and TNF-α signaling. The necrotic ischemia-reperfusion liver injury was mediated byhypoxia, ROS, and pro-inflammatory cytokines; however, necroptotic cell death was found in partial hepatectomy. The crucial role of immune cells and cell death mediators in viral hepatitis(HBV, HCV), drug-induced liver injury, non-alcoholic fatty liver disease and alcoholic liver disease in human were discussed.CONCLUSIONS: The mouse animal models of hepatitis provide a parallel approach for the study of human liver pathology. Blocking or stimulating the pathways associated with liver cell death could unveil the novel therapeutic strategies in the management of liver diseases.Hilal Ahmad Khan Muhammad Zishan Ahmad Junaid Ali Khan Muhammad Imran Arshad 2017Hepatobiliary & Pancreatic Diseases International2017,16,3:24
2Estimating the basic reproductive ratio for the Ebola outbreak in Liberia and Sierra Leone显示文摘Background:Ebola virus disease has reemerged as a major public health crisis in Africa,with isolated cases also observed globally,during the current outbreak.Methods:To estimate the basic reproductive ratio R0,which is a measure of the severity of the outbreak,we developed a SEIR(susceptible-exposed-infected-recovered)type deterministic model,and used data from the Centers for Disease Control and Prevention(CDC),for the Ebola outbreak in Liberia and Sierra Leone.Two different data sets are available:one with raw reported data and one with corrected data(as the CDC suspects under-reporting).Results:Using a deterministic ordinary differential equation transmission model for Ebola epidemic,the basic reproductive ratio R0 for Liberia resulted to be 1.757 and 1.9 for corrected and uncorrected case data,respectively.For Sierra Leone,R0 resulted to be 1.492 and 1.362 for corrected and uncorrected case data,respectively.In each of the two cases we considered,the estimate for the basic reproductive ratio was initially greater than unity leading to an epidemic outbreak.Conclusion:We obtained robust estimates for the value of R0 associated with the 2014 Ebola outbreak,and showed that there is close agreement between our estimates of R0.Analysis of our model also showed that effective isolation is required,with the contact rate in isolation less than one quarter of that for the infected non-isolated population,and that the fraction of high-risk individuals must be brought to less than 10%of the overall susceptible population,in order to bring the value of R0 to less than 1,and hence control the outbreak.Adnan Khan Mahim Naveed Muhammad Dur-e-Ahmad Mudassar Imran 2015Infectious Diseases of Poverty2015,4,1:5
3温和提取法评估老化前后土壤中菲的生物有效性显示文摘采用温和溶剂提取方法对不同老化时间土壤中的菲进行提取,研究了正丁醇、二氯甲烷、2-羟丙基-β-环糊精(2-Hydroxypropyl-beta cyclodextrin,HPCD)提取量与生物吸收之间的相关性。结果表明,温和有机溶剂(二氯甲烷、正丁醇)提取与温和HPCD提取法对菲的提取量与蚯蚓蓄积量有很好的相关性(p<0.05)。与其他温和试剂提取相比,温和正丁醇提取可以更好地预测菲在土壤中的生物有效性。张聪恺 Muhammad Imran Khan Sardar Alam Cheema 沈超峰 唐先进 申开丽 陈蕾 陈新才 施积炎 陈英旭 2011土壤学报2011,48,1:5
4Synergistic antibacterial effect of honey and Herba Ocimi Basilici against some bacterial pathogens显示文摘OBJECTIVE: To evaluate the antibacterial activity of the combination of different honey brands and methanolic fraction of Herba Ocimi Basilici using agar well diffusion assay. METHODS: The antibacterial activity was determined against thirteen pathogenic bacterial clinical isolates including six gram negative(Klebsiella pneumonia, Pseudomonas aeroginosa, Escherichia coli, Salmonella typhi, Salmonella typhimirium, Xanthomonas campestris) and six gram positive strains(Enterococcus faecalis faecalis, Bacillus subtilis, Staphylococcus aureus, Clostridium perfringens type C, Clostridium perfringens type D, Clostridium chauvoei). Agar well diffusion method was used while zones of inhibition were measured with vernier scale. RESULTS: At higher concentration, all the honey brands showed good to significant activity. The highest activity was observed for Hamdard brand honey(27.60±0.40) against Enterococcus faecalis. CONCLUSION: These results revealed that combinations of plant extracts of Herba Ocimi Basilici with honey can be used for the development of potent and novel antibacterial agents.Ali Talha Khalil Imran Khan Kafeel Ahmad Yusra Ali Khan Momin Khan Muhammad Jaseem Khan 2013Journal of Traditional Chinese Medicine2013,33,6:4
5Phyto-Toxicity of Chromium in Maize: Oxidative Damage, Osmolyte Accumulation, Anti-Oxidative Defense and Chromium Uptake显示文摘Agricultural production systems are immensely exposed to different environmental stresses in which heavy metal stress receives serious concerns. This study was conducted to explore the deleterious effects of different chromium(Cr) stress levels, i.e., 0, 30, 6090, 120, and 150 μmol L-1, on two maize genotypes, Wandan 13 and Runnong 35. Both genotypes were evaluated by measuring their growth and yield characteristics, Cr accumulation in different plant tissues, alterations in osmolyte accumulation, generation o reactive oxygen species(ROS), and anti-oxidative enzyme activity to scavenge ROS. The results showed that Cr stress decreased the leaf area, cob formation, 100-grain weight, shoot fresh biomass, and yield formation, while Cr accumulation in different maize tissues was found in the order of roots > leaves > stem > seeds in both genotypes. The increased Cr toxicity resulted in higher free proline soluble sugars and total phenolic contents, and lower soluble protein contents. However, enhanced lipid peroxidation was noticed in the forms of malondialdehyde, hydrogen peroxide(H2O2) and thiobarbituric acid reactive substance accumulation, and electrolyte leakage. The hyperactivity of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, especially glutathione peroxidase and glutathione reductase indicated that these anti-oxidative enzymes had a central role in protecting maize from Cr toxicity, especially for Wandan 13. Moreover, higher uptake and less translocation of Cr contents into the grains of Wandan 13 implied its importance as a potential candidate against soil Cr pollution.Shakeel Ahmad ANJUM Umair ASHRAF Imran KHAN Mohsin TANVEER Muhammad SHAHID Abdul SHAKOOR WANG Longchang 2017Pedosphere2017,27,2:3
6Estimating the basic reproduction number for single-strain dengue fever epidemics显示文摘Background:Dengue,an infectious tropical disease,has recently emerged as one of the most important mosquito-borne viral diseases in the world.We perform a retrospective analysis of the 2011 dengue fever epidemic in Pakistan in order to assess the transmissibility of the disease.We obtain estimates of the basic reproduction number R0 from epidemic data using different methodologies applied to different epidemic models in order to evaluate the robustness of our estimate.Results:We first estimate model parameters by fitting a deterministic ODE vector-host model for the transmission dynamics of single-strain dengue to the epidemic data,using both a basic ordinary least squares(OLS)as well as a generalized least squares(GLS)scheme.Moreover,we perform the same analysis for a direct-transmission ODE model,thereby allowing us to compare our results across different models.In addition,we formulate a direct-transmission stochastic model for the transmission dynamics of dengue and obtain parameter estimates for the stochastic model using Markov chain Monte Carlo(MCMC)methods.In each of the cases we have considered,the estimate for the basic reproduction number R0 is initially greater than unity leading to an epidemic outbreak.However,control measures implemented several weeks after the initial outbreak successfully reduce R0 to less than unity,thus resulting in disease elimination.Furthermore,it is observed that there is strong agreement in our estimates for the pre-control value of R0,both across different methodologies as well across different models.However,there are also significant differences between our estimates for the post-control value of the basic reproduction number across the two different models.Conclusion:In conclusion,we have obtained robust estimates for the value of the basic reproduction number R0 associated with the 2011 dengue fever epidemic before the implementation of public health control measures.Furthermore,we have shown that there is close agreement between our estimates for the post-control value of R0 across the different methodologies.Nevertheless,there are also significant differences between the estimates for the post-control value of R0 across the two different models.Adnan Khan Muhammad Hassan Mudassar Imran 2014Infectious Diseases of Poverty2014,3,1:3
7哈尔滨地区汛期径流量变化趋势与复杂性分析显示文摘区域水文要素复杂性研究是当今的热点问题,为了研究哈尔滨地区汛期径流量的复杂性特征及变化趋势,将R/S分析法和等概率粗粒化LZC算法引入到区域径流复杂性分析与变化趋势预测中,对地区内10个水文站点的汛期径流序列的复杂性进行诊断并对其变化趋势进行分析。研究结果表明:哈尔滨、通河、阿城、依兰、烟囱山各站未来的汛期径流量呈减少趋势,岔林河、莲花、西北河、延寿、四平山各站未来的汛期径流量呈增长趋势;各站点汛期径流序列的复杂度由高到低依次为:四平山、烟囱山、岔林河、阿城、西北河、依兰、莲花、通河、哈尔滨、延寿;从河流集水面积对其径流长程相关性和复杂性的影响可以看出,站点的河流集水面积越大,其径流量的长程相关性越强,复杂性指数越小。研究成果揭示了本地区汛期径流量的变化趋势以及复杂性演变特征,该特征可为区域径流预测及水资源优化配置提供科学依据。刘东 程晨 KHAN Muhammad Imran FAIZ Muhammad Abrar 2017华北水利水电大学学报(自然科学版)2017,38,4:3
8Physiological and biochemical appraisal for mulching and partial rhizosphere drying of cotton显示文摘Water is the main factor for the healthy life of plant.One of the main negative effects of climate change is the increasing scarcity of water that is lethal for plant.Globally,for water deficit regions(arid and semi-arid),drought is the main factor responsible for low production of agriculture,especially for cotton.Great efforts have been and are being made to find alternatives to water saving practices.This study aimed to examine the effects of partial rhizosphere drying(PRD,half of the root system irrigated at one event,and the other half irrigated in the next event,and so on)with and/or without various mulching treatments on physiological and biochemical traits of cotton.To explore this objective,we laid out experiments in completely randomized design with factorial arrangement in the Islamia University of Bahawalpur,Pakistan in 2016.Two factors included were four mulching treatments(M0,no mulching;M1,black plastic mulching;M2,wheat straw mulching;and M3,cotton sticks mulching)and two irrigation levels(I0,control(full irrigation);and I1,PRD).Fisher's analysis of variance among means of treatments was compared using least significant difference test at 5% probability level.Results revealed that the maximum plant height,leaf area,leaf gas exchange(photosynthetic rate and stomata conductance),chlorophyll,proline and total sugar contents,and enzyme activities were higher under M2 than under other three mulching treatments.As for irrigation levels,higher values of plant height,photosynthesis and water related parameters(leaf water potential,leaf osmotic potential,leaf turgor potential,etc.)were recorded.Contents of total sugar and proline and activities of antioxidant enzymes were significantly higher in PRD-treated plants than in control plants.It was concluded that combined application of PRD and mulching was more effective than the rest of the treatments used in the experiment.Similar study can be conducted in the field by applying irrigation water in alternate rows in semi-arid regions.Rashid IQBAL Muhammad A S RAZA Muhammad F SALEEM Imran H KHAN Salman AHMAD Muhammad S ZAHEER Muhammad U ASLAM Imran HAIDER 2019Journal of Arid Land2019,11,5:2
9Text Sentiment Analysis Using Frequency-Based Vigorous Features显示文摘Sentiment Analysis, an un-abating research area in text mining, requires a computational method for extracting useful information from text. In recent days, social media has become a really rich source to get information about the behavioral state of people(opinion) through reviews and comments. Numerous techniques have been aimed to analyze the sentiment of the text, however, they were unable to come up to the complexity of the sentiments. The complexity requires novel approach for deep analysis of sentiments for more accurate prediction. This research presents a three-step Sentiment Analysis and Prediction(SAP) solution of Text Trend through K-Nearest Neighbor(KNN). At first, sentences are transformed into tokens and stop words are removed. Secondly, polarity of the sentence, paragraph and text is calculated through contributing weighted words, intensity clauses and sentiment shifters. The resulting features extracted in this step played significant role to improve the results. Finally, the trend of the input text has been predicted using KNN classifier based on extracted features. The training and testing of the model has been performed on publically available datasets of twitter and movie reviews. Experiments results illustrated the satisfactory improvement as compared to existing solutions. In addition, GUI(Hello World) based text analysis framework has been designed to perform the text analytics.Abdul Razzaq Muhammad Asim Zulqrnain Ali Salman Qadri Imran Mumtaz Dost Muhammad Khan Qasim Niaz 2019China Communications2019,16,12:2
10The relationship between energy consumption, economic growth and carbon dioxide emissions in Pakistan显示文摘Developing countries are facing the problem of environmental degradation.Environmental degradation is caused by the use of non-renewable energy consumptions for economic growth but the consequences of environmental degradation cannot be ignored.This primary purpose of this study is to investigate the nexus between energy consumption,economic growth and CO_(2) emission in Pakistan by using annual time series data from 1965 to 2015.The estimated results of ARDL indicate that energy consumption and economic growth increase the CO_(2) emissions in Pakistan both in short run and long run.Based on the estimated results it is recommended that policy maker in Pakistan should adopt and promote such renewable energy sources that will help to meet the increased demand for energy by replacing old traditional energy sources such as coal,gas,and oil.Renewable energy sources are reusable that can reduce the CO_(2) emissions and also ensure sustainable economic development of Pakistan.Muhammad Kamran Khan Muhammad Imran Khan Muhammad Rehan 2020Financial Innovation2020,6,1:2
11Assessment of Pyrene Bioavailabili- ty in Soil by Mild Hydroxypropyl-13-Cyclodextrin Ex- traction 显示文摘Muhammad Imran Khan Sardar Alam Cheema Cha- ofeng Shen 2011Archives of Environmental Contamina- tion and Toxicology2011,60,1:1
12Impact of temperature on yield and related traits in cotton genotypes显示文摘Cotton growth and development is influenced by various uncontrollable environmental conditions. Temperature variations in the field can be created by planting at different dates. The objective of the present study was to evaluate the effect of planting dates and thermal temperatures(growing degree days) on yield of 4 cotton genotypes, viz., CIM-598, CIM-599, CIM-602 and Ali Akbar-703. Plants were subjected to 6 planting dates during 2013 and 2014 in a trial conducted in randomized complete block design with four replications. For boll number, boll weight and seed cotton yield, cotton genotypes exhibited significant differences, CIM-599 produced the highest seed cotton yield of 2 062 kg ha^(–1) on account of maximum boll number and boll weight. The highest seed cotton yield was recorded in planting dates from 15 th April to 1st May whereas early and delayed planting reduced the yield due to less accumulation of heat units. Regression analysis revealed that increase of one unit(15 days) from early to optimum date(15th March to 15 th April) increased yield by 93.58 kg ha^(–1). Delay in planting also decreased the seed cotton yield with the same ratio. Thus it is concluded that cotton must be sown from 15 th April to 1st May to have good productivity in this kind of environment.Kalim Ullah Niamatullah Khan Zahid Usman Rehmat Ullah Fazal Yazdan Saleem Syed Asif Imran Shah Muhammad Salman 2016Journal of Integrative Agriculture2016,15,3:1
13Application of soft computing models to hourly weather analysis in southern Saskatchewan, Canada显示文摘Imran Maqsood Muhammad Riaz Khan Guo H Huang 2005Engineer-ing Applications of Artificial Intelligence2005,18,1:1
14Stable Huh-7 cell lines expressing non-structural proteins of genotype 1a of hepatitis C virus显示文摘Imran Shahid Sana Gull Bushra Ijaz Waqar Ahmad Muhammad Ansar Sultan Asad Humera Kausar Muhammad Tahir Sarwar Muhammad Kazim Khan Sajida Hassan 2013Journal of Virological Methods2013,,1:1
15Privacy and security federated reference architecture for Internet of Things显示文摘Physical objects are getting connected to the Internet at an exceptional rate,making the idea of the Internet of Things(IoT)a reality.The IoT ecosystem is evident everywhere in the form of smart homes,health care systems,wearables,connected vehicles,and industries.This has given rise to risks associated with the privacy and security of systems.Security issues and cyber attacks on IoT devices may potentially hinder the growth of IoT products due to deficiencies in the architecture.To counter these issues,we need to implement privacy and security right from the building blocks of IoT.The IoT architecture has evolved over the years,improving the stack of architecture with new solutions such as scalability,management,interoperability,and extensibility.This emphasizes the need to standardize and organize the IoT reference architecture in federation with privacy and security concerns.In this study,we examine and analyze 12 existing IoT reference architectures to identify their shortcomings on the basis of the requirements addressed in the standards.We propose an architecture,the privacy-federated IoT security reference architecture(PF-IoT-SRA),which interprets all the involved privacy metrics and counters major threats and attacks in the IoT communication environment.It is a step toward the standardization of the domain architecture.We effectively validate our proposed reference architecture using the architecture trade-off analysis method(ATAM),an industry-recognized scenario-based approach.Musab KAMAL Imran RASHID Waseem IQBAL Muhammad Haroon SIDDIQUI Sohaib KHAN Ijaz AHMAD 2023Frontiers of Information Technology & Electronic Engineering2023,24,4:1
16Breeding for pre-harvest sprouting resistance in bread wheat under rainfed conditions显示文摘Pre-harvest sprouting in wheat is the germination of seeds within the spikes when rains occur after or during grain ripening, which occurs commonly in the barani tract of Pakistan. Therefore, 10 cultivars and five advanced lines of spring bread wheat were evaluated for pre-harvest sprouting resistance. After natural rainfall,seeds were immediately collected from the wet spikes and tested for germinating ability. Three different germination tests were applied to hand-threshed seed:(1) spikes threshed on the day of sampling and germination tested immediately,(2) spikes threshed on the day of sampling and germination tested 1 week later, and(3) spikes threshed 1 week after sampling and germination test immediately after threshing. Seeds and spikes kept for 1 week were place on blotting paper at room temperature.Cultivars BARS-09, 09 FJ17, Doukkala-12, NARC-09 and Ouassou-20 exhibited higher sprouting resistance while other genotypes were susceptible to pre-harvest sprouting in each of the three tests. A diallel crossing was conducted with six susceptible and two resistant genotypes to assess the genetic behavior of pre-harvest sprouting resistance.The combining ability(CA) demonstrated a higher proportion of additive genetic effects for sprouting resistance, because of higher variance of general and specific CA for both parameters under study. Doukkala-12 and BARS-09 showed increased pre-harvest sprouting resistance in their F1 descendants.Muhammad ZEESHAN Waheed ARSHAD Muhammad Imran KHAN Shiraz ALI Ali NAWAZ Amina BATOOL Muhammad TARIQ Muhammad Imran AKRAM Muhammad Amjad ALI 2018Frontiers of Agricultural Science and Engineering2018,5,2:1
17Effectiveness of radiative heat flux in MHD flow of Jeffrey-nanofluid subject to Brownian and thermophoresis diffusions显示文摘Our interest here in this investigation is to explore the thermophoresis and Brownian motion characteristics in flow induced by stretched surface.Electrically conducted Jeffrey material formulates the flow equation.Linear forms of stretching and free stream velocities are imposed.Nonlinear radiation and convective heating processes describe the phenomenon of heat transfer.Passive controls of nanoparticles are considered on the boundary.The compatible transformations produce the strong nonlinear differential systems.The problems are computed analytically utilizing HAM.Converge nee domain is detennined and major results are concluded for different parameters involved.Heat transfer rate and drag force are also explained for various physical variables.Our analysis reveals that heat transfer rate augments via larger radiation parameter and Biot number.Moreover larger Brownian motion and thermophoresis parameters have opposite characteristics on concentration field.Muhammad Ijaz Khan Tasawar Hayat Muhammad Waqas Ahmed Alsaedi Muhammad Imran Khan 2019Journal of Hydrodynamics2019,31,2:1
18Salinity Stress in Wheat:Effects,Mechanisms and Management Strategies显示文摘Salinity stress is a major threat to global food production and its intensity is continuously increasing because of anthropogenic activities.Wheat is a staple food and a source of carbohydrates and calories for the majority of people across the globe.However,wheat productivity is adversely affected by salt stress,which is associated with a reduction in germination,growth,altered reproductive behavior and enzymatic activity,disrupted photosynthesis,hormonal imbalance,oxidative stress,and yield reductions.Thus,a better understanding of wheat(plant)behavior to salinity stress has essential implications to devise counter and alleviation measures to cope with salt stress.Different approaches including the selection of suitable cultivars,conventional breeding,and molecular techniques can be used for facing salt stress tolerance.However,these techniques are tedious,costly,and labor-intensive.Management practices are still helpful to improve the wheat performance under salinity stress.Use of arbuscular mycorrhizal fungi,plant growth-promoting rhizobacteria,and exogenous application of phytohormones,seed priming,and nutrient management are important tools to improve wheat performance under salinity stress.In this paper,we discussed the effect of salinity stress on the wheat crop,possible mechanisms to deal with salinity stress,and management options to improve wheat performance under salinity conditions.Mahmoud F.Seleiman Muhammad Talha Aslam Bushra Ahmed Alhammad MuhammadUmair Hassan Rizwan Maqbool Muhammad Umer Chattha Imran Khan Harun Ireri Gitari Omer S.Uslu Rana Roy Martin Leonardo Battaglia 2022Phyton-International Journal of Experimental Botany2022,91,4:1
19Zingiber officinale ameliorates allergic asthma via suppression of Th2-mediated immune response显示文摘Asad Mahmood Khan Muhammad Shahzad M. B. Raza Asim Muhammad Imran Arham Shabbir 2014Pharmaceutical Biology2014,,:1
20Privacy Protection with Dynamic Pseudonym-Based Multiple Mix-Zones Over Road Networks显示文摘In this research we proposed a strategy for location privacy protection which addresses the issues related with existing location privacy protection techniques. Mix-Zones and pseudonyms are considered as the basic building blocks for location privacy; however, continuously changing pseudonyms process at multiple locations can enhance user privacy. It has been revealed that changing pseudonym at improper time and location may threat to user's privacy. Moreover, certain methods related to pseudonym change have been proposed to attain desirable location privacy and most of these solutions are based upon velocity, GPS position and direction of angle. We analyzed existing methods related to location privacy with mix zones, such as RPCLP, EPCS and MODP, where it has been observed that these methods are not adequate to attain desired level of location privacy and suffered from large number of pseudonym changes. By analyzing limitations of existing methods, we proposed Dynamic Pseudonym based multiple mix zone(DPMM) technique, which ensures highest level of accuracy and privacy. We simulate our data by using SUMO application and analysis results has revealed that DPMM outperformed existing pseudonym change techniques and achieved better results in terms of acquiring high privacy with small number of pseudonym change.Qasim Ali Arain Zhongliang Deng Imran memon Asma Zubedi Jichao Jiao Aisha Ashraf Muhammad Saad Khan 2017China Communications2017,14,4:1
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