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| 1 | 利用RAPD-PCR方法鉴定我国烟粉虱的生物型(英文)显示文摘收集了国内北京、山东、广东和海南等 14个省市 2 3个地区的蔬菜、园林花卉和杂草上的 2 3个烟粉虱Bemisiatabaci(Gennadius)种群 ,根据报道合成了一个随机引物H1 6 ,运用RAPD PCR技术对所收集的烟粉虱种群进行了生物型鉴定。结果表明在 2 3个烟粉虱种群中 ,有 17个种群同属于危害严重的“B生物型” ,这些种群主要分布在交通便利的城市或沿海地区 ,而非B生物型则主要分布在交通不便的山区或内陆。 | 邱宝利 任顺祥 温硕洋 Nasser S.MANDOUR | 2003 | 昆虫学报2003,46,5: | 52 |
| 2 | MicroRNA-328 is associated with (non-small) cell lung cancer (NSCLC) brain metastasis and mediates NSCLC migration显示文摘 | Arora S Ranade AR Tran NL Nasser S Sridhar S Korn RL Ross JT Dhruv H Foss KM Sibenaller Z Ryken T Gotway MB Kim S Weiss GJ | 2011 | 中国神经肿瘤杂志2011,9,1: | 30 |
| 3 | GRADE指南:Ⅷ.证据质量评价--间接性显示文摘直接证据来自直接比较我们关注的干预措施用于我们关注的患者人群,并测量患者重要结局的研究。间接证据可由以下4种方式之一产生。第一,患者可能与我们关注的患者不同(适用性一词常用于这类间接性)。第二,所检验的干预措施可能与我们关注的干预措施不同。有关患者和干预措施间接性的决策取决于对生物或社会因素差异是否大到可能使效应尺度出现预期的较大差异的考虑。第三,结果可能有别于最初设定的结局指标——如替代结果本身不重要,但测量之是基于替代结果的变化反映患者重要结局变化这一假设。第四类间接性在概念上与前三类不同,发生于临床医生必须在未经直接比较的两种干预措施间做出选择时。这种情况下比较治疗方案需要特定的统计方法,并根据患者人群、联合干预措施、结局测量指标及备选干预措施试验方法的差异程度,将证据级别降低1或2级。 | Gordon Guyatt Andrew D.Oxman Regina Kunz James Woodcock Jan Brozek Mark Helfand Pablo Alonso-Coello Yngve Falck-Ytter Roman Jaeschke Gunn Vist Elie A.Akl Piet N Post Susan Norris Joerg Meerpohl Mona Nasser 代表GRADE工作组 李幼平 杨晓妍 李鸿浩 | 2011 | 中国循证医学杂志2011,11,12: | 30 |
| 4 | Clinical and cost impact of intravenous proton pump inhibitor use in non-ICU patients显示文摘AIM:To assess the appropriateness of the indication and route of administration of proton-pump-inhibitors (PPIs) and their associated cost impact. METHODS:Data collection was performed prospec-tively during a 6-mo period on 340 patients who re-ceived omeprazole intravenously during their hospital stay in non-intensive care floors. Updated guidelines were used to assess the appropriateness of the indication and route of administration. RESULTS:Complete data collection was available for 286 patients which were used to assess intravenous (IV) PPIs utilization. Around 88% of patients were receiving PPIs for claimed stress ulcer prophylaxis (SUP) indication; of which,only 17% met the guideline criteria for SUP indication,14% met the criteria for non-steroidal-anti-inflammatory drugs-induced ulcer prophylaxis,while the remaining 69% were identifi ed as having an unjustified indication for PPI use. Theinitiation of IV PPIs was appropriate in 55% of pa-tients. Half of these patients were candidates for switching to the oral dosage form during their hos-pitalization,while only 36.7% of these patients were actually switched. The inappropriate initiation of PPIs via the IV route was more likely to take place on the medical floor than the surgical floor (53% vs 36%,P = 0.003). The cost analysis associated with the appro-priateness of the indication for PPI use as well as the route of administration of PPI revealed a possible saving of up to $17 732.5 and $14 571,respectively. CONCLUSION:This study highlights the over-utili-zation of IV PPIs in non-intensive care unit patients. Restriction of IV PPI use for justified indications and route of administration is recommended. | Soumana C Nasser Jeanette G Nassif Hani I Dimassi | 2010 | World Journal of Gastroenterology2010,16,8: | 23 |
| 5 | Olive oil consumption and non-alcoholic fatty liver disease显示文摘The clinical implications of non-alcoholic fatty liver diseases(NAFLD)derive from their potential to progress to fibrosis and cirrhosis.Inappropriate dietary fat intake,excessive intake of soft drinks,insulin resistance and increased oxidative stress results in increased free fatty acid delivery to the liver and increased hepatic triglyceride(TG)accumulation.An olive oil-rich diet decreases accumulation of TGs in the liver,improves postprandial TGs,glucose and glucagonlike peptide-1 responses in insulin-resistant subjects, and upregulates glucose transporter-2 expression in the liver.The principal mechanisms include:decreased nuclear factor-kappaB activation,decreased lowdensity lipoprotein oxidation,and improved insulin resistance by reduced production of inflammatory cytokines(tumor necrosis factor,interleukin-6)and improvement of jun N-terminal kinase-mediated phosphorylation of insulin receptor substrate-1.The beneficial effect of the Mediterranean diet is derived from monounsaturated fatty acids,mainly from olive oil.In this review,we describe the dietary sources of the monounsaturated fatty acids,the composition of olive oil,dietary fats and their relationship to insulin resistance and postprandial lipid and glucose responses in non-alcoholic steatohepatitis,clinical and experimental studies that assess the relationship between olive oil and NAFLD,and the mechanism by which olive oil ameliorates fatty liver,and we discuss future perspectives. | Nimer Assy Faris Nassar Gattas Nasser Maria Grosovski | 2009 | World Journal of Gastroenterology2009,15,15: | 22 |
| 6 | Long-term outcomes of hepatocellular carcinoma that underwent chemoembolization for bridging or downstaging显示文摘BACKGROUND Prospective study of 200 patients with hepatocellular carcinoma(HCC)that underwent liver transplant(LT)after drug-eluting beads transarterial chemoembolization(DEB-TACE)for downstaging versus bridging.Overall survival and tumor recurrence rates were calculated,eligibility for LT,time on the waiting list and radiological response were compared.After TACE,only patients within Milan Criteria(MC)were transplanted.More patients underwent LT in bridging group.Five-year post-transplant overall survival,recurrence-free survival has no difference between the groups.Complete response was observed more frequently in bridging group.Patients in DS group can achieve posttransplant survival and HCC recurrence-free probability,at five years,just like patients within MC in patients undergoing DEB-TACE.AIM To determine long-term outcomes of patients with HCC that underwent LT after DEB-TACE for downstaging vs bridging.METHODS Prospective cohort study of 200 patients included from April 2011 through June 2014.Bridging group included patients within MC.Downstaging group(out of MC)was divided in 5 subgroups(G1 to G5).Total tumor diameter was≤8 cm for G1,2,3,4(n=42)and was>8 cm for G5(n=22).Downstaging(n=64)and bridging(n=136)populations were not significantly different.Overall survival and tumor recurrence rates were calculated by the Kaplan-Meier method.Additionally,eligibility for LT,time on the waiting list until LT and radiological response were compared.RESULTS After TACE,only patients within MC were transplanted.More patients underwent LT in bridging group 65.9%(P=0.001).Downstaging population presented:higher number of nodules 2.81(P=0.001);larger total tumor diameter 8.09(P=0.001);multifocal HCC 78%(P=0.001);more post-transplantation recurrence 25%(P=0.02).Patients with maximal tumor diameter up to 7.05 cm were more likely to receive LT(P=0.005).Median time on the waiting list was significantly longer in downstaging group 10.6 mo(P=0.028).Five-year posttransplant overall survival was 73.5%in downstaging and 72.3%bridging groups(P=0.31),and recurrence-free survival was 62.1%in downstaging and 74.8%bridging groups(P=0.93).Radiological response:complete response was observed more frequently in bridging group(P=0.004).CONCLUSION Tumors initially exceeding the MC down-staged after DEB-TACE,can achieve post-transplant survival and HCC recurrence-free probability,at five years,just like patients within MC in patients undergoing DEB-TACE. | Breno Boueri Affonso Francisco Leonardo Galastri Joaquim Mauricio da Motta Leal Filho Felipe Nasser Priscila Mina Falsarella Rafael Noronha Cavalcante Marcio Dias de Almeida Guilherme Eduardo Goncalves Felga Leonardo Guedes Moreira Valle Nelson Wolosker | 2019 | World Journal of Gastroenterology2019,25,37: | 21 |
| 7 | Cirrhotic cardiomyopathy:A cardiologist's perspective显示文摘Cardiac dysfunction is frequently observed in patients with cirrhosis, and has long been linked to the direct toxic effect of alcohol. Cirrhotic cardiomyopathy(CCM) has recently been identified as an entity regardless of the cirrhosis etiology. Increased cardiac output due to hyperdynamic circulation is a pathophysiological hallmark of the disease. The underlying mechanisms involved in pathogenesis of CCM are complex and involve various neurohumoral and cellular pathways, including the impaired β-receptor and calcium signaling, altered cardiomyocyte membrane physiology, elevated sympathetic nervous tone and increased activity of vasodilatory pathways predominantly through the actions of nitric oxide, carbon monoxide and endocannabinoids. The main clinical features of CCM include attenuated systolic contractility in response to physiologic or pharmacologic strain, diastolic dysfunction, electrical conductance abnormalities and chronotropic incompetence. Particularly the diastolic dysfunction with impaired ventricularrelaxation and ventricular filling is a prominent feature of CCM.The underlying mechanism of diastolic dysfunction in cirrhosis is likely due to the increased myocardial wall stiffness caused by myocardial hypertrophy,fibrosis and subendothelial edema,subsequently resulting in high filling pressures of the left ventricle and atrium.Currently,no specific treatment exists for CCM.The liver transplantation is the only established effective therapy for patients with end-stage liver disease and associated cardiac failure.Liver transplantation has been shown to reverse systolic and diastolic dysfunction and the prolonged QT interval after transplantation.Here,we review the pathophysiological basis and clinical features of cirrhotic cardiomyopathy,and discuss currently available limited therapeutic options. | Natig Gassanov Evren Caglayan Nasser Semmo Gero Massenkeil Fikret Er | 2014 | World Journal of Gastroenterology2014,20,42: | 18 |
| 8 | 蚜小蜂和粉虱座壳孢对烟粉虱的控制作用研究显示文摘研究了烟粉虱两种寄生性天敌桨角蚜小蜂 (Eretmocerussp .)和粉虱座壳孢 (Aschersoniaaley rodis)单独使用和联合使用时对烟粉虱种群的控制作用 .结果表明 ,在单独进行控制时 ,在一个世代内按 5× 10 6个孢子·ml-1喷施粉虱座壳孢 2次 ,对烟粉虱种群的控制作用达 95 .74 % ,按每株植株 3头雌蜂的密度释放桨角蚜小蜂 2次 ,对烟粉虱种群的控制作用达 5 7.5 8% .在两者联合控制时 ,一个世代内喷施粉虱座壳孢 2次 ,再释放桨角蚜小蜂 1次或 2次 ,对烟粉虱种群的控制作用达 97.0 2 %~ 97.91% ,烟粉虱种群增长趋势指数低于 1,种群数量逐渐下降 .联合使用时 ,桨角蚜小蜂和粉虱座壳孢间无消极影响 . | 邱宝利 任顺祥 肖燕 Nasser Said Mandour | 2003 | 应用生态学报2003,14,12: | 17 |
| 9 | 疾病传播输入输出流的时空特征分析——以北京SARS流行为例显示文摘为更好揭示传染病流行的个体受感染.发病一就诊.康复的时空过程变化模式以及区域之间的信息流与物质流的传播网络结构特征,基于2002~2003年中国SARS病例数据,选取SARS流行的三个典型空间位置信息:工作单位或住址、发病地点以及报告单位,从感染个体和空间区域两个角度来探索病毒感染扩展的输入与输出传播机制,定义并探讨了北京市SARS传播输入一输出流(In—OutFlow)的概念与流行病学特征.采用空间统计分析方法和网络特征分析方法,探索了北京市外部输入.输出流的高风险时空热点以及网络结构特征,并对北京市内部输入.输出流传播网络的空间自相关性与异质性、时空演化规律以及网络结构特征进行了全面分析.结果表明:(1)外部输入流集中在山西和广东,而外部输出流较为分散,主要是广东以及山东等北部省份,且防控措施重点应分别是SARS爆发的早中期与初期;(2)内部输出病例在整体区域上存在显著正自相关性特征,高危人群集中在20~60岁的医务与民工等中青年人群;(3)市中心区的若干区县是SARS传播高风险热点区域,西北方位市郊是次级高风险区域,而东北方位市郊则相对安全;(4)在内部传播网络中各区县节点存在显著小世界特征且具有信息流和物质流的异质性特征,市郊通州区与昌平区是潜在的高风险热点区域,顺义区与怀柔区等节点承载了极低的物质流和信息流信息,是相对的低风险冷点区域.基于输入.输出流的探索与分析更有助于揭示SARS流行过程中的潜在时空演化特征与规律,可为应急决策与防控措施提供更有效的理论依据. | 胡碧松 龚建华 周洁萍 孙麇 杨荔阳 夏宇 IBRAHIM Abdoul Nasser | 2013 | 中国科学:地球科学2013,43,9: | 13 |
| 10 | Is there any correlation between vitamin D insufficiency and diabetic retinopathy?显示文摘AIM: To determine a relation between vitamin D level,which is an inhibitor of angiogenesis, and diabetic retinopathy and its risk factorsMETHODS: In a clinic-based cross sectional study two hundred and thirty-five type 2 diabetic patients older than 20 y were selected. Patients were classified according to ophthalmologic examination as following:no diabetic retinopathy(NDR)(n =153), non-proliferative diabetic retinopathy(NPDR)(n =64) and proliferative diabetic retinopathy(PDR)(n =18). Study subjects were tested for fasting blood glucose, glycated hemoglobin A1C(Hb A1C), lipid profile, microalbuminuria, Hs CRP,IGF1, insulin(in patients without history of insulin taking)and 25 hydroxy vitamin D [25(OH) D] levels. Vitamin D insufficiency was defined according to 25(OH) D level less than 30 ng/m L. The relationship between diabetic retinopathy and serum 25(OH) D insufficiency was evaluated.RESULTS: The prevalence of diabetic retinopathy was34.8% in our patients. Long duration of diabetes,hypertension, poor glycemic control, diabetic nephropathy, hyperinsulinemia and insulin resistance were risk factors for diabetic retinopathy but 25(OH) D level was not significant different between NDR, NPDR and PDR groups. Correlation between 25(OH) D level and other known risk factors of diabetic retinopathy was not significant.CONCLUSION: This study did not find any association between diabetic retinopathy and its severity and vitamin D insufficiency. Vitamin D insufficiency is not related to risk factors of diabetic retinopathy. | Shokoufeh Bonakdaran Nasser Shoeibi | 2015 | International Journal of Ophthalmology(English edition)2015,8,2: | 13 |
| 11 | 热处理改善齿科用钛合金的体外腐蚀、磨损和力学性能显示文摘研究热处理对新型Ti20Nb13Zr (TNZ)合金组织、力学性能、耐磨性和人工唾液(AS)体外腐蚀防护性能的影响。采用X射线衍射(XRD)、扫描电镜(SEM)等进行结构和显微组织分析。采用电化学阻抗谱和线性极化电阻技术研究样品在AS中浸泡168 h后的体外耐腐蚀性能。采用线性往复摩擦计对其摩擦特性进行研究。SEM分析结果表明,固溶处理和时效影响α相的尺寸和分布。空冷和时效处理后样品具有最高的显微硬度和宏观硬度,其耐磨性分别比未处理样品高25%和30%。冷却速率对TNZ合金的耐腐蚀性有显著影响。经过处理的样品在AS中浸泡168 h后,腐蚀速率降低50%。经炉冷和时效处理的样品在AS中浸泡168 h后具有最好的耐腐蚀性。在经过处理的样品中,时效样品表现出更优异的力学性能、耐磨性能和体外耐腐蚀性能。 | Mohamed HUSSEIN Akeem YADESINA Madhan KUMAR Mohamed AZEEM Ahmad SOROUR Nasser AL-AQEELI | 2021 | Transactions of Nonferrous Metals Society of China2021,31,4: | 9 |
| 12 | Characteristics of common solid liver lesions and recommendations for diagnostic workup显示文摘Due to the widespread clinical use of imaging modalities such as ultrasonography,computed tomography and magnetic resonance imaging (MRI),previously unsuspected liver masses are increasingly being found in asymptomatic patients.This review discusses the various characteristics of the most common solid liver lesions and recommends a practical approach for diagnostic workup.Likely diagnoses include hepatocellular carcinoma (the most likely;a solid liver lesion in a cirrhotic liver) and hemangioma (generally presenting as a mass in a non-cirrhotic liver).Focal nodular hyperplasia and hepatic adenoma should be ruled out in young women.In 70% of cases,MRI with gadolinium differentiates between these lesions.Fine needle core biopsy or aspiration,or both,might be required in doubtful cases.If uncertainty persists as to the nature of the lesion,surgical resection is recommended.If the patient is known to have a primary malignancy and the lesion was found at tumor staging or follow up,histology is required only when the nature of the liver lesion is doubtful. | Nimer Assy Gattas Nasser Agness Djibre Zaza Beniashvili Saad Elias Jamal Zidan | 2009 | World Journal of Gastroenterology2009,15,26: | 9 |
| 13 | 油田钻井废水的物化组合处理技术显示文摘对化学混凝膜分离、化学混凝活性碳吸附组合工艺处理油田钻井废水进行了试验研究。通过对4种混凝剂混凝对比试验,确定最佳混凝剂为聚合氯化铁(PFC)。在pH=8.1,助凝剂聚丙烯酰胺(PAM,质量分数0.5%)投加量w(PAM)为10mL·L-1,PFC(质量分数10%)投加量w(KC87)为10mL·L-1的条件下,化学需氧量(COD)去除率达95.3%。混凝出水经膜分离深度处理后,没有达到排放要求。混凝出水经活性炭深度处理获得了较好的效果。在选取的4种活性炭中,KC87粉末状果壳活性炭的吸附效果最好,在吸附时间为1h、投加量w(KC87)为3g·L-1的条件下,可使混凝出水中COD的去除率达75.3%。经PFC化学混凝和KC87活性炭吸附组合工艺处理后,废水COD总去除率达到97.4%,其他污染物也得到了明显的去除,使得最终出水达到了国家废水综合排放标准一级水平。 | 李秀金 Goran Nasser 康佳丽 李荣平 | 2005 | 北京化工大学学报(自然科学版)2005,32,4: | 8 |
| 14 | Lower baseline ALT cut-off values and HBV DNA levels better differentiate HBeAg(-) chronic hepatitis B patients from inactive chronic carriers显示文摘AIM:To determine whether new cut-off values for alanine aminotransferase(ALT)and baseline hepatitis B virus(HBV)DNA levels better differentiate HBeAg(-) chronic hepatitis B(CHB)patients from inactive chronic carriers. METHODS:Ninety-one patients[32 HBeAg(+)CHB, 19 inactive carriers and 40 HBeAg(-)CHB]were followed up for 2 years and were tested for HBV DNA levels by a PCR-based assay.ALT was tested twice during the last 6 mo using new cut-off values:ULN(upper limit of normal)30 IU/L for males,19 IU/L for females. Diagnostic accuracy,sensitivity,specificity,positive and negative predictive values were calculated by discriminant analysis. RESULTS:When using the revised ALT cut-off values, the lowest optimal HBV DNA level that differentiated HBeAg(-)CHB patients from inactive carriers was 50000 copies/mL.The diagnostic accuracy of HBV DNA to determine inactive carriers with a cut-off of 50000 copies/mL was similar to the previously recommended cut-off of 100 000 copies/mL(91%).HBV DNA levels were lower than the cut-off value in 95%of inactive carriers and in 28%of HBeAg(-)CHB patients.With ALT<30 IU/L in men and<19 IU/L in women and HBV DNA levels<100 000 copies/mL,the risk of CHB is 5%.On the other hand,if ALT values were>30 IU in men and>19 IU in women and baseline HBV DNA levels were>100000 copies/mL,the risk is 86%. CONCLUSION:New cut-off values for ALT together with HBV DNA levels proposed by AASLD(American Association for the Study of Liver Diseases)and NIH (National Institute of Health)consensus seem appropriate to characterize inactive carriers. | Nimer Assy Zaza Beniashvili Agness Djibre Gattas Nasser Maria Grosovski William Nseir | 2009 | World Journal of Gastroenterology2009,15,24: | 7 |
| 15 | Clinical significance of Helicobacter pylori cagA and iceA genotype status显示文摘AIM:To study the presence of Helicobacter pylori(H.pylori) virulence factors and clinical outcome in H.pylori infected patients.METHODS:A prospective analysis of ninety nine H.pylori-positive patients who underwent endoscopy in our Endoscopy suite were included in this study.DNA was isolated from antral biopsy samples and the presence of cagA,iceA,and iceA2 genotypes were determined by polymerase chain reaction and a reverse hybridization technique.Screening for H.pylori infection was performed in all patients using the rapid urease test(CLO-Test).RESULTS:From a total of 326 patients who underwent endoscopy for upper gastrointestinal symptoms,99 patients were determined to be H.pylori-positive.Peptic ulceration was seen in 33 patients(33%).The main virulence strain observed in this cohort was the cagA gene isolated in 43 patients.cagA was associated with peptic ulcer pathology in 39.5%(17/43) and in 28%(16/56) of non-ulcer patients.IceA1 was present in 29 patients(29%) and iceA2 in 15 patients(15%).Ulcer pathology was seen in 39%(11/29) of patients with iceA1,while 31%(22/70) had normal findings.The corresponding values for iceA2 were 33%(5/15) and 33%(28/84),respectively.CONCLUSION:Virulence factors were not common in our cohort.The incidence of factors cagA,iceA1 and iceA2 were very low although variations were noted in different ethnic groups. | Nasser Amjad Hussain Ali Osman Najibah Abdul Razak Junaini Kassian Jeffri Din Nasuruddin bin Abdullah | 2010 | World Journal of Gastroenterology2010,16,35: | 7 |
| 16 | Influence of proton pump inhibitors on gastritis diagnosis and pathologic gastric changes显示文摘AIM: To investigate the influence of proton pump inhibitors(PPIs) exposure on the diagnosis of Helicobacter pylori(H. pylori) gastritis and intestinal metaplasia.METHODS: Chronic PPI use is associated with masking of H. pylori infection. Patients with H. pylori infection are predisposed to gastric and duodenal ulcers, and long-term infection with this organism has been associated with gastric mucosal atrophy and serious long-term complications, such as gastric lymphoma and adenocarcinoma. Three hundred patients diagnosed with gastritis between January 2008 and April 2010 were included in our study. The computerized medical database of these patients was reviewed retrospectively in order to assess whether the type of gastritis diagnosed(H. pylori vs non-H. pylori gastritis) is influenced by PPI exposure. H. pylori density was graded as low, if corresponding to mild density following the Updated Sydney System, or high, if corresponding to moderate or severe densities in the Updated Sydney System.RESULTS: Patients were equally distributed between males and females with a median age at the time of diagnosis of 50 years old(range: 20-87). The histological types of gastritis were classified as H. pylori gastritis(n = 156, 52%) and non-H. pylori gastritis(n = 144, 48%). All patients with non-H. pylori gastritis had inactive chronic gastritis. Patients with no previous PPI exposure were more likely to be diagnosed with H. pylori gastritis than those with previous PPI exposure(71% vs 34.2%, P < 0.001). Intestinal metaplasiawas more likely to be detected in the latter patients(1.4% vs 6.5%, P = 0.023). Multivariate analysis has also demonstrated that in the presence of previous PPI exposure(OR = 0.217, 95%CI: 0.123-0.385), GERD(OR = 0.317, 95%CI: 0.132-0.763, P = 0.01), alcohol intake(OR = 0.396, 95%CI: 0.195-0.804, P = 0.01), the detection of H. pylori was less likely. Chronic use of PPIs may mask H. pylori infections promoting the diagnosis of non-H. pylori gastritis and leads to a significant drop in H. pylori densities and to an increased risk of intestinal metaplasia.CONCLUSION: The use of PPIs masks H. pylori infection, promotes the diagnosis of non-H. pylori inactive chronic gastritis diagnosis, and increases the incidence of intestinal metaplasia. | Soumana C Nasser Mahmoud Slim Jeanette G Nassif Selim M Nasser | 2015 | World Journal of Gastroenterology2015,21,15: | 7 |
| 17 | Characterizing Spatial Variability of Soil Textural Fractions and Fractal Parameters Derived from Particle Size Distributions显示文摘Soil particle size distribution(PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives of this work were: 1) to partition PSD of 75 soil samples, collected from a flat field in the University of Guilan, Iran, into two scaling domains using a piecewise fractal model to evaluate the relationships between fractal dimensions of scaling domains and soil clay, silt, and sand fractions and 2) to assess the potential of fractal parameters as an index used in a geostatistical approach reflecting the spatial variability of soil texture. Features of PSD of soil samples were studied using fractal geometry, and geostatistical techniques were used to characterize the spatial variability of fractal and soil textural parameters. There were two scaling domains for the PSD of soil samples. The fractal dimensions of these two scaling domains(D_1 and D_2) were then used to characterize different ranges of soil particle sizes and their relationships to the soil textural parameters. There was a positive correlation between D_1 and clay content(R^2= 0.924), a negative correlation between D_1 and silt content(R^2= 0.801), and a negative correlation between D_2 and sand content(R^2= 0.913). The geometric mean diameter of soil particles had a negative correlation with D_1(R^2= 0.569) and D_2(R^2= 0.682). Semivariograms of fractal dimensions and soil textural parameters were calculated and the maps of spatial variation of D_1 and D_2 and soil PSD parameters were provided using ordinary kriging. The results showed that there were also spatial correlations between D_1 and D_2 and particle size fractions.According to the semivariogram models and validation parameters, the fractal parameters had powerful spatial structure and could better describe the spatial variability of soil texture. | Meysam MOHAMMADI Mahmoud SHABANPOUR Mohammad Hossein MOHAMMADI Nasser DAVATGAR | 2019 | Pedosphere2019,29,2: | 7 |
| 18 | Polymeric vs hydroxyapatite-based scaffolds on dental pulp stem cell proliferation and differentiation显示文摘AIM: To evaluate adhesion, proliferation and differentiation of human dental pulp stem cells(h DPSCs) on four commercially available scaffold biomaterials. METHODS: hD PSCs were isolated from human dental pulp tissues of extracted wisdom teeth and established in stem cell growth medium. h DPSCs at passage 3-5 were seeded on four commercially available scaffold biomaterials, SureO ss(Allograft), Cerabone(Xenograft), PLLA(Synthetic), and OSTEON Ⅱ Collagen(Composite), for 7 and 14 d in osteogenic medium. Cell adhesion and morphology to the scaffolds were evaluated by scanning electron microscopy(SEM). Cell proliferation and differentiation into osteogenic lineage were evaluated using DNA counting and alkaline phosphatase(ALP) activity assay, respectively. RESULTS: All scaffold biomaterials except Sure Oss(Allograft) supported h DPSC adhesion, proliferation and differentiation. hD PSCs seeded on PLLA(Synthetic) scaffold showed the highest cell proliferation and attachment as indicated with both SEM and DNA counting assay. Evaluating the osteogenic differentiation capability of hD PSCs on different scaffold biomaterials with ALP activity assay showed high level of ALP activity on cells cultured on PLLA(Synthetic) and OSTEON ⅡCollagen(Composite) scaffolds. SEM micrographs also showed that in the presence of Cerabone(Xenograft) and OSTEON Ⅱ Collagen(Composite) scaffolds, the h DPSCs demonstrated the fibroblastic phenotype with several cytoplasmic extension, while the cells on PLLA scaffold showed the osteoblastic-like morphology, round-like shape. CONCLUSION: PLLA scaffold supports adhesion, proliferation and osteogenic differentiation of hD PSCs. Hence, it may be useful in combination with hD PSCs for cell-based reconstructive therapy. | Arash Khojasteh Saeed Reza Motamedian Maryam Rezai Rad Mehrnoosh Hasan Shahriari Nasser Nadjmi | 2015 | World Journal of Stem Cells2015,7,10: | 5 |
| 19 | Intrahepatic distribution of hepatitis B virus antigens in patients with and without hepatocellular carcinoma显示文摘AIM: To study the intrahepatic expression of hepatitis B surface antigen(HBs Ag) and hepatitis B core antigen(HBc Ag) in chronic hepatitis B patients with and without hepatocellular carcinoma. METHODS: A total of 33 chronic hepatitis B patients(mean age of 40.3 ± 2.5 years), comprising of 14 HBe Ag positive and 19 HBe Ag negative patients; and 13 patients with hepatitis B virus related hepatocellular carcinoma(mean age of 49.6 ± 4.7 years), were included in our study. Immunohistochemical staining for HBc Ag and HBs Ag was done using standard streptavidin-biotin-immunoperoxidase technique on paraffin-embedded liver biopsies. The HBc Agand HBs Ag staining distributions and patterns were described according to a modified classification system. RESULTS: Compared to the HBe Ag negative patients, the HBe Ag positive patients were younger, had higher mean HBV DNA and alanine transaminases levels. All the HBe Ag positive patients had intrahepatic HBc Ag staining; predominantly with 'diffuse' distribution(79%) and 'mixed cytoplasmic/nuclear ' pattern(79%). In comparison, only 5% of the HBe Ag-negative patients had intrahepatic HBc Ag staining. However, the intrahepatic HBs Ag staining has wider distribution among the HBe Ag negative patients, namely; majority of the HBe Ag negative cases had 'patchy' HBs Ag distribution compared to 'rare' distribution among the HBe Ag positive cases. All but one patient with HCC were HBe Ag negative with either undetectable HBV DNA or very low level of viremia. Intrahepatic HBc Ag and HBs Ag were seen in 13(100%) and 10(77%) of the HCC patients respectively. Interestingly, among the 9 HCC patients on anti-viral therapy with suppressed HBV DNA, HBc Ag and HBs Ag were detected in tumor tissues but not the adjacent liver in 4(44%) and 1(11%) patient respectively. CONCLUSION: Isolated intrahepatic HBc Ag and HBs Ag can be present in tumors of patients with suppressed HBV DNA on antiviral therapy; that may predispose them to cancer development. | Parham Safaie Mugilan Poongkunran Ping-Ping Kuang Asad Javaid Carl Jacobs Rebecca Pohlmann Imad Nasser Daryl TY Lau | 2016 | World Journal of Gastroenterology2016,22,12: | 5 |
| 20 | Single-and double-dose of platelet-rich plasma versus hyaluronic acid for treatment of knee osteoarthritis: A randomized controlled trial显示文摘BACKGROUND Platelet-rich plasma(PRP)and hyaluronic acid have been shown to be useful in the treatment of knee osteoarthritis.However,investigations comparing the efficacy of these two drugs together are insufficient.AIM To compare the outcomes of PRP vs hyaluronic acid injections in three groups of patients with bilateral knee osteoarthritis.METHODS This randomized controlled trial study involved 95 patients.Thirty-one subjects received a single injection of PRP(group PRP-1),33 subjects received two injections of PRP at an interval of 3 wk(group PRP-2)and 31 subjects received three injections of hyaluronic acid at 1-wk intervals(group hyaluronic acid).The patients were investigated prospectively at the enrollment and at 4-,8-and 12-wk follow-up with the Western Ontario and McMaster Universities Arthritis Index(WOMAC)and Visual Analogue Scale questionnaires.RESULTS Percentages of patients experiencing at least a 30%decrease in the total score for the WOMAC pain subscale from baseline to wk 12 of the intervention were 86%,100%and 0%in the groups PRP-1,PRP-2 and hyaluronic acid,respectively(P<0.001).The mean total WOMAC scores for groups PRP-1,PRP-2 and hyaluronic acid at baseline were 63.71,61.57 and 63.11,respectively.The WOMAC scores were significantly improved at final follow-up to 42.5,35.32 and 57.26,respectively.The highest efficacy of PRP was observed in both groups at wk 4 with about 50%decrease in the symptoms compared with about 25%decrease for hyaluronic acid.Group PRP-2 had higher efficacy than group PRP-1.No major adverse effects were found during the study.CONCLUSION PRP is a safe and efficient therapeutic option for treatment of knee osteoarthritis.It was demonstrated to be significantly better than hyaluronic acid.We also found that the efficacy of PRP increases after multiple injections. | Mehdi Tavassoli Nasser Janmohammadi Akram Hosseini Soraya Khafri Seyed Mokhtar Esmaeilnejad-Ganji | 2019 | World Journal of Orthopedics2019,10,9: | 5 |