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Hepatitis B virus,HBx mutants and their role in hepatocellular carcinoma 被引量:30
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作者 ashraf Ali Hany Abdel-Hafiz +7 位作者 Mohd Suhail Amany Al-Mars Mohammad Khalid Zakaria Kaneez Fatima Sultan Ahmad Esam Azhar Adeel Chaudhary Ishtiaq Qadri 《World Journal of Gastroenterology》 SCIE CAS 2014年第30期10238-10248,共11页
Hepatocellular carcinoma(HCC)is one of the leading causes of death induced by cancer in the modern world and majority of the cases are related to chronic hepatitis B virus(HBV)infection.HBV-encoded X protein(HBx)is kn... Hepatocellular carcinoma(HCC)is one of the leading causes of death induced by cancer in the modern world and majority of the cases are related to chronic hepatitis B virus(HBV)infection.HBV-encoded X protein(HBx)is known to play a pivotal role in the pathogenesis of viral induced HCC.HBx is a multifunctional protein of17 kDa which modulates several cellular processes by direct or indirect interaction with a repertoire of host factors resulting in HCC.HBX might interfere with several cellular processes such as oxidative stress,DNA repair,signal transduction,transcription,protein degradation,cell cycle progression and apoptosis.A number of reports have indicated that HBx is one of the most common viral ORFs that is often integrated into the host genome and its sequence variants play a crucial role in HCC.By mutational or deletion analysis it was shown that carboxy terminal of HBx has a likely role in protein-protein interactions,transcriptional transactivation,DNA repair,cell,signaling and pathogenesis of HCC.The accumulated evidence thus far suggests that it is difficult to understand the mechanistic nature of HBx associated HCC,and HBx mediated transcriptional transactivation and signaling pathways may be a major determinant.This article addresses the role of HBx in the development of HCC with particular emphasis on HBx mutants and their putative targets. 展开更多
关键词 Hepatitis B virus Hepatocellular carcinoma Transcription factors Apoptosis EPIGENETICS MUTANTS Tumor necrosis factor Activating protein Transforming growth factor Mitogen activated protein kinase
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Relationship between acrosin activity of human spermatozoa and oxidative stress 被引量:27
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作者 Adel A.Zalata ashraf H.Ahmed +2 位作者 Shyam S.R.Allamaneni Frank H.Comhaire Ashok Agarwal 《Asian Journal of Andrology》 SCIE CAS CSCD 2004年第4期313-318,共6页
Aim: To study the association between seminal oxidative stress and human sperm acrosin activity. Methods: It is a prospective study consisting of 30 infertile men and 12 fertile normozoospermic volunteers. A full hist... Aim: To study the association between seminal oxidative stress and human sperm acrosin activity. Methods: It is a prospective study consisting of 30 infertile men and 12 fertile normozoospermic volunteers. A full history, clinical examination and scrotal ultrasound were done to exclude other related factors such as smoking and varicocele. Presence of white blood cells (WBCs) in semen samples was evaluated by peroxidase staining. Lipid peroxidation in spermatozoa was induced after incubating with ferrous sulphate (4 mmol/L) and sodium ascorbate (20 mmol/L). Induced peroxidation of spermatozoa was assessed by determining the production of thiobarbituric acid reactive substances (TBARS). Acrosin activity was measured using the gelatinolysis technique. The halo diameters around the sperm heads and the percentages of spermatozoa showing halo formation were evaluated. An acrosin activity index was calculated by multiplying the halo diameter by the halo formation rate. Results: A significant difference was observed in acrosin activity parameters and TBARS levels between samples with WBCs (>1×106/mL of ejaculate) and those without. This difference was also noted between the normozoospermic and the oligoasthenoteratozoospermic semen samples. The TBARS production by spermatozoa had a significant negative correlation with the acrosin activity index (r = -0.89, P <0.001). Conclusion: The presence of oxidative stress in an individual with leukocytospermia and/or abnormal semen parameters is associated with impaired sperm function as measured by its acrosin activity. 展开更多
关键词 ACROSIN gelatinolysis reactive oxygen species lipid peroxidation LEUKOCYTOSPERMIA SPERMATOZOA oligo-astheno-teratozoospermia INFERTILITY
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Early postoperative feeding in resectional gastrointestinal surgical cancer patients 被引量:23
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作者 Emma J Osland Muhammed ashraf Memon 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2010年第4期187-191,共5页
Malnutrition is present in the majority of patients presenting for surgical management of gastrointestinal malignancies,due to the effects of the tumour and preoperative anti-neoplastic treatments.The traditional prac... Malnutrition is present in the majority of patients presenting for surgical management of gastrointestinal malignancies,due to the effects of the tumour and preoperative anti-neoplastic treatments.The traditional practice of fasting patients until the resumption of bowel function threatens to further contribute to the malnutrition experienced by these patients.Furthermore,the rationale behind this traditional practice has been rendered obsolete through developments in anaesthetic agents and changes to postoperative analgesia practices.Conversely,there is a growing body of literature that consistently demonstrates that providing oral or tube feeding proximal to the anastomosis within 24 h postoperatively,is not only safe,but might be associated with significant benefits to the postoperative course.Early post operative feeding should therefore be adopted as a standard of care in oncology patients undergoing gastrointestinal resections. 展开更多
关键词 Early FEEDING SURGERY META-ANALYSIS RANDOMISED controlled trials
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春茶采摘末期遮荫对其生长和品质的影响 被引量:18
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作者 胡永光 江丰 +1 位作者 MAHMOOD ashraf 刘鹏飞 《农业机械学报》 EI CAS CSCD 北大核心 2018年第1期283-289,共7页
为延长春茶采摘期,提高其产量,进行了遮阳网遮荫栽培试验研究。根据不同遮光率和不同遮荫高度,在茶园中设置4个处理:60%遮光率+2.0 m遮荫高度(T1)、40%遮光率+2.0 m遮荫高度(T2)、40%遮光率+2.5 m遮荫高度(T3)和无遮荫的对照处理(CK);... 为延长春茶采摘期,提高其产量,进行了遮阳网遮荫栽培试验研究。根据不同遮光率和不同遮荫高度,在茶园中设置4个处理:60%遮光率+2.0 m遮荫高度(T1)、40%遮光率+2.0 m遮荫高度(T2)、40%遮光率+2.5 m遮荫高度(T3)和无遮荫的对照处理(CK);试验全程分为前、中、后期。试验研究以上各处理遮阳网内外温、湿度环境的差异,茶树新稍、叶片生长状况和茶芽叶品质指标。结果表明:遮荫后,茶树冠层处的日最高气温显著降低,遮光率越高降幅越大,最大降幅为3.9℃;08:00—17:00的最低相对湿度均增大,遮光率越高增幅越大,最大增幅为9.01%;新稍长度、粗度均增加,以T1处理的增幅最大,分别为22.3%和13.5%;新稍叶片的叶绿素相对含量和芽叶含水率,随着遮光率增大而增高;与CK处理相比,T1处理的新稍叶片日平均净光合速率变大,而T2和T3显著变小;T3处理增加了茶叶水浸出物、茶多酚和酚氨比,降低了氨基酸含量,导致茶汤浓厚、苦涩味加重;而T1处理在试验前期增加了咖啡碱含量,降低了水浸出物含量和酚氨比。综上所述,在春茶采摘末期采用60%遮光率的遮阳网进行遮荫栽培,对于保持春茶品质、延长采摘期具有重要的生产指导意义。 展开更多
关键词 春茶 遮荫栽培 遮光率 生长 品质
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Liver diseases in pregnancy: Diseases not unique to pregnancy 被引量:17
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作者 ashraf A Almashhrawi Khulood T Ahmed +2 位作者 Rubayat N Rahman Ghassan M Hammoud Jamal A Ibdah 《World Journal of Gastroenterology》 SCIE CAS 2013年第43期7630-7638,共9页
Pregnancy is a special clinical state with several normal physiological changes that influence body organs including the liver.Liver disease can cause significant morbidity and mortality in both pregnant women and the... Pregnancy is a special clinical state with several normal physiological changes that influence body organs including the liver.Liver disease can cause significant morbidity and mortality in both pregnant women and their infants.Few challenges arise in reaching an accurate diagnosis in light of such physiological changes.Laboratory test results should be carefully interpreted and the knowledge of what normal changes to expect is prudent to avoid clinical misjudgment.Other challenges entail the methods of treatment and their safety for both the mother and the baby.This review summarizes liver diseases that are not unique to pregnancy.We focus on viral hepatitis and its mode of transmission,diagnosis,effect on the pregnancy,the mother,the infant,treatment,and breast-feeding.Autoimmune hepatitis,primary biliary cirrhosis,primary sclerosing cholangitis,Wilson’s disease,Budd Chiari and portal vein thrombosis in pregnancy are also discussed.Pregnancy is rare in patients with cirrhosis because of the metabolic and hormonal changes associated with cirrhosis.Variceal bleeding can happen in up to 38%of cirrhotic pregnant women.Management of portal hypertension during pregnancy is discussed.Pregnancy increases the pathogenicity leading to an increase in the rate of gallstones.We discuss some of the interventions for gallstones in pregnancy if symptoms arise.Finally,we provide an overview of some of the options in managing hepatic adenomas and hepatocellular carcinoma during pregnancy. 展开更多
关键词 Liver PREGNANCY VIRAL hepatitis AUTOIMMUNE CIRRHOSIS GALLSTONES ADENOMA
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Acousto-optical modulation of thin film lithium niobate waveguide devices 被引量:16
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作者 LUTONG CAI ashraf MAHMOUD +4 位作者 MSI KHAN MOHAMED MAHMOUD TAMAL MUKHERJEE JAMES BAIN GIANLUCA PIAZZA 《Photonics Research》 SCIE EI CSCD 2019年第9期1003-1013,共11页
Due to its strong piezoelectric effect and photo-elastic property, lithium niobate is widely used for acousto-optical applications. However, conventional bulk lithium niobate waveguide devices exhibit a large footprin... Due to its strong piezoelectric effect and photo-elastic property, lithium niobate is widely used for acousto-optical applications. However, conventional bulk lithium niobate waveguide devices exhibit a large footprint and limited light–sound interaction resulting from the weak guiding of light. Here, we report the first acousto-optical modulators with surface acoustic wave generation, phononic cavity, and low-loss photonic waveguide devices monolithically integrated on a 500 nm thick film of lithium niobate on an insulator. Modulation efficiency was optimized by properly arranging the propagation directions of surface acoustic waves and optical guided modes.The effective photo-elastic coefficient extracted by comparing the first and third harmonic modulation signals from an on-chip Mach–Zehnder interferometer indicates the excellent acousto-optical properties of lithium niobate are preserved in the thin film implementation. Such material property finding is of crucial importance in designing various types of acousto-optical devices. Much stronger amplitude modulation was achieved in a high Q(>300,000) optical resonator due to the higher optical sensitivity. Our results pave the path for developing novel acousto-optical devices using thin film lithium niobate. 展开更多
关键词 AOM Acousto-optical modulation of THIN film LITHIUM NIOBATE WAVEGUIDE devices
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Cytokine- and chemokine-induced inflammatory colorectal tumor microenvironment: Emerging avenue for targeted therapy 被引量:13
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作者 Ajaz A.Bhat Sabah Nisar +15 位作者 Mayank Singh Bazella ashraf Tariq Masoodi Chandra P.Prasad Atul Sharma Selma Maacha Thasni Karedath Sheema Hashem Syed Besina Yasin Puneet Bagga Ravinder Reddy Michael P.Frennaux Shahab Uddin Punita Dhawan Mohammad Haris Muzafar A.Macha 《Cancer Communications》 SCIE 2022年第8期689-715,共27页
Colorectal cancer(CRC)is a predominant life-threatening cancer,with liver and peritoneal metastases as the primary causes of death.Intestinal inflammation,a known CRC risk factor,nurtures a local inflammatory environ... Colorectal cancer(CRC)is a predominant life-threatening cancer,with liver and peritoneal metastases as the primary causes of death.Intestinal inflammation,a known CRC risk factor,nurtures a local inflammatory environment enriched with tumor cells,endothelial cells,immune cells,cancer-associated fibroblasts,immunosuppressive cells,and secretory growth factors.The complex interactions of aberrantly expressed cytokines,chemokines,growth factors,and matrix-remodeling enzymes promote CRC pathogenesis and evoke systemic responses that affect disease outcomes.Mounting evidence suggests that these cytokines and chemokines play a role in the progression of CRC through immunosuppression and modulation of the tumor microenvironment,which is partly achieved by the recruitment of immunosuppressive cells.These cells impart features such as cancer stem cell-like properties,drug resistance,invasion,and formation of the premetastatic niche in distant organs,promoting metastasis and aggressive CRC growth.A deeper understanding of the cytokineand chemokine-mediated signaling networks that link tumor progression and metastasis will provide insights into the mechanistic details of disease aggressiveness and facilitate the development of novel therapeutics for CRC.Here,we summarized the current knowledge of cytokine-and chemokine-mediated crosstalk in the inflammatory tumor microenvironment,which drives immunosuppression,resistance to therapeutics,and metastasis during CRC progression.We also outlined the potential of this crosstalk as a novel therapeutic target for CRC.The major cytokine/chemokine pathways involved in cancer immunotherapy are also discussed in this review. 展开更多
关键词 CHEMOKINE colorectal cancer CYTOKINE drug resistance epithelial-mesenchymal transition IMMUNOSUPPRESSION immunotherapy inflammation metastasis tumor microenvironment
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Ag/Ag_3PO_4/g-C_3N_4三元复合光催化剂的制备及其可见光驱动下的光催化活性增强(英文) 被引量:14
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作者 沈凯 Mohammed ashraf Gondal +4 位作者 Rashid Ghulam Siddique 施珊 王斯琦 孙江波 徐庆宇 《催化学报》 SCIE EI CAS CSCD 北大核心 2014年第1期78-84,共7页
报道了一种新型Ag/Ag3PO4/g-C3N4三元复合光催化剂的制备及其半导体界面处的快速载流子分离所引起的光催化活性的显著增强效应.通过X射线衍射,扫描电子显微镜,紫外-可见吸收光谱以及光致发光光谱等就其晶体结构、形貌、组分、光学吸收... 报道了一种新型Ag/Ag3PO4/g-C3N4三元复合光催化剂的制备及其半导体界面处的快速载流子分离所引起的光催化活性的显著增强效应.通过X射线衍射,扫描电子显微镜,紫外-可见吸收光谱以及光致发光光谱等就其晶体结构、形貌、组分、光学吸收以及载流子的快速分离行为进行了表征与分析.以罗丹明B作为模型化合物分子,研究发现,所制备的Ag/Ag3PO4/g-C3N4三元复合光催化剂在可见光照射下表现出比Ag3PO4以及Ag3PO4/g-C3N4二元催化剂更为优异的光催化活性.研究认为,Ag3PO4表面尺寸约为40 nm的Ag纳米粒子在可见光下受激所产生的等离子表面共振效应以及Ag3PO4与g-C3N4界面处所形成的类似异质结结构对所制备的Ag/Ag3PO4/g-C3N4三元复合光催化剂光催化活性的显著增强起到重要作用. 展开更多
关键词 银纳米粒子 磷酸银 石墨型氮化碳 表面等离子共振 异质结
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Soil Microbiological Activity and Carbon Dynamics in the Current Climate Change Scenarios:A Review 被引量:13
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作者 Javid A.SOFI Aabid H.LONE +5 位作者 Mumtaz A.GANIE Naseer A.DAR Sajad A.BHAT Malik MUKHTAR Mohd ashraf DAR Shazia RAMZAN 《Pedosphere》 SCIE CAS CSCD 2016年第5期577-591,共15页
Microbial activities are affected by a myriad of factors with end points involved in nutrient cycling and carbon sequestration issues.Because of their prominent role in the global carbon balance and their possible rol... Microbial activities are affected by a myriad of factors with end points involved in nutrient cycling and carbon sequestration issues.Because of their prominent role in the global carbon balance and their possible role in carbon sequestration, soil microbes are very important organisms in relation to global climate changes. This review focuses mainly on the responses of soil microbes to climate changes and subsequent effects on soil carbon dynamics. An overview table regarding extracellular enzyme activities(EAA) with all relevant literature data summarizes the effects of different ecosystems under various experimental treatments on EAA. Increasing temperature, altered soil moisture regimes, and elevated carbon dioxide significantly affect directly or indirectly soil microbial activities.High temperature regimes can increase the microbial activities which can provide positive feedback to climate change, whereas lower moisture condition in pedosystem can negate the increase, although the interactive effects still remain unanswered. Shifts in soil microbial community in response to climate change have been determined by gene probing, phospholipid fatty acid analysis(PLFA),terminal restriction length polymorphism(TRFLP), and denaturing gradient gel electrophoresis(DGGE), but in a recent investigations,omic technological interventions have enabled determination of the shift in soil microbe community at a taxa level, which can provide very important inputs for modeling C sequestration process. The intricacy and diversity of the soil microbial population and how it responds to climate change are big challenges, but new molecular and stable isotope probing tools are being developed for linking fluctuations in microbial diversity to ecosystem function. 展开更多
关键词 carbon cycling carbon dioxide carbon exchange carbon sequestration microbe community soil enzymes soil moisture soil temperature
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Microbial Degradation of Organophosphate Pesticides: A Review 被引量:12
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作者 Shardendu KUMAR Garima KAUSHIK +3 位作者 Mohd ashraf DAR Surendra NIMESH Ulrico Javier LOPEZ-CHUKEN Juan Francisco VILLARREAL-CHIU 《Pedosphere》 SCIE CAS CSCD 2018年第2期190-208,共19页
Pesticides have become an inevitable part of the modern environment as they are widely used in agriculture,household,and public health sectors and,hence,are extensively distributed throughout most ecosystems.Currently... Pesticides have become an inevitable part of the modern environment as they are widely used in agriculture,household,and public health sectors and,hence,are extensively distributed throughout most ecosystems.Currently,organophosphate pesticides are the most commercially favored group of pesticides,with large application areas all over the world.Depending on their fate,these organophosphorus compounds may become bioavailable for microbial degradation.Environmental microbes,such as Aspergillus,Pseudomonas,Chlorella,and Arthrobacter,are capable of coupling a variety of physical and biochemical mechanisms for the degradation of organophosphate pesticides,including adsorption,hydrolysis of P–O alkyl and aryl bonds,photodegradation,and enzymatic mineralization.Enzymes,such as esterase,diisopropyl fluorophosphatase,phosphotriesterase,somanase,parathion hydrolase,and paraoxonase,have been isolated from microbes to study and understand the catabolic pathways involved in the biotransformation of these xenobiotic compounds.This review highlights various aspects of biodegradation of organophosphate pesticides along with biological and molecular characterization of some organophosphate pesticide-degrading bacteria. 展开更多
关键词 BIODEGRADATION ENZYMES INSECTICIDE metabolic PATHWAYS pesticide-degrading bacteria ORGANOPHOSPHORUS compound xenobiotics
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Potential mechanisms of hepatitis B virus induced liver injury 被引量:12
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作者 Mohd Suhail Hany Abdel-Hafiz +5 位作者 ashraf Ali Kaneez Fatima Ghazi A Damanhouri Esam Azhar Adeel GA Chaudhary Ishtiaq Qadri 《World Journal of Gastroenterology》 SCIE CAS 2014年第35期12462-12472,共11页
Chronic active hepatitis(CAH) is acknowledged as an imperative risk factor for the development of liver injury and hepatocellular carcinoma.The histological end points of CAH are chronic inflammation,fibrosis and cirr... Chronic active hepatitis(CAH) is acknowledged as an imperative risk factor for the development of liver injury and hepatocellular carcinoma.The histological end points of CAH are chronic inflammation,fibrosis and cirrhosis which are coupled with increased DNA synthesis in cirrhotic vs healthy normal livers.The potential mechanism involved in CAH includes a combination of processes leading to liver cell necrosis,inflammation and cytokine production and liver scaring(fibrosis).The severity of liver damage is regulated by Hepatitis B virus genotypes and viral components.The viral and cellular factors that contribute to liver injury are discussed in this article.Liver injury caused by the viral infection affects many cellular processes such as cell signaling,apoptosis,transcription,DNA repair which in turn induce radical effects on cell survival,growth,transformation and maintenance.The consequence of such perturbations is resulted in the alteration of bile secretion,gluconeogenesis,glycolysis,detoxification and metabolism of carbohydrates,proteins,fat and balance of nutrients.The identification and elucidation of the molecular pathways perturbed by the viral proteins are important in order to design effective strategy to minimize and/or restore the hepatocytes injury. 展开更多
关键词 Hepatitis B virus Hepatitis B virus genotype Hepatocellular carcinoma Woodchuck hepatitis virus Ground squirrel hepatitis virus Peripheral blood mononuclear cells Interferon regulatory factor 7 Interleukin-1 receptor-associated kinase 4 TNF receptor-associated factor 3
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Liver diseases in pregnancy: Diseases unique to pregnancy 被引量:11
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作者 Khulood T Ahmed ashraf A Almashhrawi +2 位作者 Rubayat N Rahman Ghassan M Hammoud Jamal A Ibdah 《World Journal of Gastroenterology》 SCIE CAS 2013年第43期7639-7646,共8页
Pregnancy is a special clinical state with several normal physiological changes that influence body organs including the liver.Liver disease can cause significant morbidity and mortality in both pregnant women and the... Pregnancy is a special clinical state with several normal physiological changes that influence body organs including the liver.Liver disease can cause significant morbidity and mortality in both pregnant women and their infants.This review summarizes liver diseases that are unique to pregnancy.We discuss clinical conditions that are seen only in pregnant women and involve the liver;from Hyperemesis Gravidarum that happens in 1out of 200 pregnancies and Intrahepatic Cholestasis of Pregnancy(0.5%-1.5%prevalence),to the more frequent condition of preeclampsia(10%prevalence)and its severe form;hemolysis,elevated liver enzymes,and a low platelet count syndrome(12%of pregnancies with preeclampsia),to the rare entity of Acute Fatty Liver of Pregnancy(incidence of 1 per 7270 to 13000deliveries).Although pathogeneses behind the development of these aliments are not fully understood,theories have been proposed.Some propose the special physiological changes that accompany pregnancy as a precipitant.Others suggest a constellation of factors including both the mother and her fetus that come together to trigger those unique conditions.Reaching a timely and accurate diagnosis of such conditions can be challenging.The timing of the condition in relation toward which trimester it starts at is a key.Accurate diagnosis can be made using specific clinical findings and blood tests.Some entities have well-defined criteria that help not only in making the diagnosis,but also in classifying the disease according to its severity.Management of these conditions range from simple medical remedies to measures such as immediate termination of the pregnancy.In specific conditions,it is prudent to have expert obstetric and medical specialists teaming up to help improve the outcomes. 展开更多
关键词 LIVER PREGNANCY HYPEREMESIS gravidarum Intrahepatic CHOLESTASIS Hemolysis elevated LIVER enzymes and a low platelet count Preeclampsia ECLAMPSIA Acute fatty LIVER
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Boundary of Cretaceous and Paleogene continental deposits in Zeya-Bureya Basin,Amur(Heilongjiang)River region 被引量:11
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作者 Valentina S. Markevich Eugenia V. Bugdaeva +1 位作者 Abdul R. ashraf SUN Get 《Global Geology》 2011年第3期144-159,共16页
It was conducted the comparison of palynological assemblages of the Middle Tsagayan,Upper Tsagayan subformations,Furao and Wuyun formations from Zeya-Bureya Basin of Amur (Heilongjiang) River region with assemblages o... It was conducted the comparison of palynological assemblages of the Middle Tsagayan,Upper Tsagayan subformations,Furao and Wuyun formations from Zeya-Bureya Basin of Amur (Heilongjiang) River region with assemblages obtained from the marine deposits of Northeast Russia,Sakhalin,Kuril,and Hokkaido Islands,dated by ammonites,foraminifers and other invertebrates. Based on detail correlation,the geological age of the terrestrial beds was defined. The guide fossils are recognized Marsypiletes cretacea,Tricolpites variexi- nus,Aquilapollenites conatus,A. stelkii,A. rombicus,Integricorpus bellum,Pseudointegricorpus clarireticula- tus,Triprojectus amoenus,Orbiculapollis lucidus,Wodehouseia aspera,Quercoidites minor,which had last oc- currence in the late Maastrichtian. The Danian palynofloras usually are dominated by Triatriopollenites plicoides and T. confusus. The species Anacolosidites subtrudens,Aquilapollenites proceros,A. spinulosus have last occurrence in the Danian. The K-T (K-Pg) boundary in the terrestrial deposits is defined in the base of the Upper Tsagayan Subformation and the base of the lower part of the Wuyun Formation. The latter is represented by aleuropelite to fine-grained sandstones. The change of taxonomical composition of palynospectra in similar environments could be determined by real change of flora at the Mesozoic and Cenozoic boundary,but not by changes of lithological facies or depositional environment,generally. 展开更多
关键词 palynoflore CRETACEOUS PALEOGENE BOUNDARY Zeya-Bureya Basin
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IL28B polymorphism and cytomegalovirus predict response to treatment in Egyptian HCV type 4 patients 被引量:8
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作者 Mostafa K El Awady Noha G Bader El Din +5 位作者 ashraf Tabll Yaser El Hosary ashraf O Abdel Aziz Hesham El Khayat Mohsen Salama Tawfeek H Abdelhafez 《World Journal of Gastroenterology》 SCIE CAS 2013年第2期290-298,共9页
AIM:To test whether the status of positive cytomegalovirus(CMV) DNA detection adds to the predictive value of IL28B and to further categorize C/T allele carriers.METHODS:This study included 166 chronic hepatitis C(CHC... AIM:To test whether the status of positive cytomegalovirus(CMV) DNA detection adds to the predictive value of IL28B and to further categorize C/T allele carriers.METHODS:This study included 166 chronic hepatitis C(CHC) patients who received combined interferon and ribavirin therapy for 48 wk,84 spontaneous hepatitis C virus(HCV) resolvers who were positive for IgG anti-HCV antibody and negative for HCV RNA,and 100 healthy subjects who were negative for both HCV antibodies and RNA as controls.Genomic DNA from peripheral blood was used for IL28B rs.12979860 single nucleotide polymorphism(SNP) and CMV DNA detection.A 139 bp fragment containing IL28B SNP was amplified in all subjects by polymerase chain reaction using a specifically designed primer.Then the IL28B rs.12979860 SNP was detected by restriction fragment length polymorphism(RFLP) genotyping.The presence of CMV DNA was tested by amplification of the gB1 gene using nested polymerase chain reaction.The role of CMV and IL28B rs.12979860 SNP genotypes in determining the response rate to combined interferon therapy and clinical status of patients were statistically analyzed.RESULTS:Current data showed that 67% of patients carrying the IL28B 12979860 C/C allele had a sustained viral response(SVR) while the genotypes C/T and TT were associated with lower SVR rates,50% and 48%,respectively.SVR rates for the C/C allele were lower than other HCV genotypes and/or other populations.Genotype CC was associated with the response to interferon(P = 0.025).Genotype C/C was reduced from 48% in controls to 14% in CHC patients suggesting its protective role against progression to chronicity.The majority of spontaneously cleared subjects(86%) were C/C,confirming its protective role.The C/T allele was present in 71% of CHC patients compared with 38% of controls,so the use of IL28B SNP genotyping only in these patients may be of little value as a predictor of response.CMV reactivation occurred in 40% of CHC patients.Co-infection with CMV seriously diminished the response to interf 展开更多
关键词 HEPATITIS C INTERLEUKIN 28B Genetic POLYMORPHISMS Human CYTOMEGALOVIRUS Spontaneous CLEARANCE
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碳纤维布粘贴加固BFRP筋-ECC-混凝土组合梁受弯性能研究 被引量:8
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作者 葛文杰 宗耀锋 +5 位作者 仇胜伟 宋婉蓉 王仪 陆伟刚 曹大富 ashraf Ashour 《建筑结构学报》 EI CAS CSCD 北大核心 2021年第S01期302-311,共10页
工程结构服役期间经常由于使用功能改变或使用荷载增加而需要对结构进行加固改造。为研究经碳纤维布粘贴加固后的玄武岩纤维增强塑料(BFRP)筋-工程用水泥基复合材料(ECC)-混凝土组合梁的受弯性能,对3组共12根不同ECC高度替换率(0、0.29... 工程结构服役期间经常由于使用功能改变或使用荷载增加而需要对结构进行加固改造。为研究经碳纤维布粘贴加固后的玄武岩纤维增强塑料(BFRP)筋-工程用水泥基复合材料(ECC)-混凝土组合梁的受弯性能,对3组共12根不同ECC高度替换率(0、0.29和0.58)的BFRP筋-ECC-混凝土组合梁底分别粘贴1、2和3层碳纤维布的加固构件及未加固构件进行静力受弯性能试验。研究碳纤维布粘贴层数和ECC高度替换率对组合梁受弯承载力和破坏形态的影响。试验结果表明:采用受拉性能优异的ECC替代受拉区部分混凝土形成的ECC-混凝土组合梁不仅可提高构件承载力,还可有效改善构件抵抗开裂和变形的能力;组合梁底粘贴3层碳纤维布,裂缝宽度可降至未加固试件的10%,受弯承载力提高20%,挠度降低50%。借鉴钢筋混凝土理论,基于合理的基本假定和简化的材料本构模型,提出粘贴碳纤维布加固的组合梁受弯承载力计算式,并给出碳纤维布强度折减系数,理论预测值与试验实测值吻合良好。 展开更多
关键词 组合梁 BFRP筋 ECC 混凝土 碳纤维布加固 静力试验 受弯性能
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Seed Treatment with Auxins Modulates Growth and Ion Partitioning in Salt-stressed Wheat Plants 被引量:10
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作者 Muhammad lqbal Muhammad ashraf 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2007年第7期1003-1015,共13页
Experiments were performed to determine whether seed priming with different concentrations (100, 150, and 200 mg/L) of auxins (indoleacetic acid (IAA), indolebutyric acid (IBA), or their precursor tryptophane ... Experiments were performed to determine whether seed priming with different concentrations (100, 150, and 200 mg/L) of auxins (indoleacetic acid (IAA), indolebutyric acid (IBA), or their precursor tryptophane (Trp)) could alter salinity induced perturbances in salicylic acid and ion concentrations and, hence, growth in wheat (Triticum aestivum L.) cultivars, namely M.H.-97 (salt intolerant) and tnqtab-91 (salt tolerant). Primed and non-primed seeds were sown in Petri dishes in a growth room, as well as in a field treated with 15 dS/m NaCl salinity. All priming agents, except IBA, increased the final germination percentage in both cultivars. The seedlings of either cultivar raised from Trp-treated seeds had greater dry biomass when under salt stress. In field experiments, Trp priming was much more effective in mediating the increase in grain yield, irrespective of the cultivar, under salt stress. The alleviatory effect of Trp was found to be associated with reduced uptake of Na^+ in the roots and subsequent translocation to the shoots, as well as increased partitioning of Ca^+ in the roots of salt-stressed wheat plants. Plants of both cultivars raised from Trp-and IAA-treated seeds accumulated free salicylic acid in their leaves when under salt stress. Overall, the Trp priming-induced improvement in germination and the subsequent growth of wheat plants could be related to ion homeostasis when under salt stress. The possible involvement of salicylic acid in the Trp priming-induced better growth under Conditions of salt stress is discussed. 展开更多
关键词 AUXINS GROWTH ion homeostasis salicylic acid seed priming tryptophane wheat.
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The issue of lymphadenectomy during laparoscopic gastrectomy for gastric carcinoma 被引量:10
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作者 Muhammed ashraf Memon Nick Butler Breda Memon 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2010年第2期65-67,共3页
Surgical resection remains the mainstay of treatment for gastric cancer.Laparoscopic assisted gastrectomy has failed to gain universal acceptance as an alternative to the open approach for a number of reasons,one of w... Surgical resection remains the mainstay of treatment for gastric cancer.Laparoscopic assisted gastrectomy has failed to gain universal acceptance as an alternative to the open approach for a number of reasons,one of which includes the issue of oncological radicality in terms of lymph node dissection.Nodal status,which is one of the most crucial and independent predictors of patient survival,therefore has been examined both in single institutional trials and also in randomised controlled trials especially on early gastric cancer.The issue of oncological adequacy for laparoscopic lymph node harvesting for advanced gastric cancer remains a contentious issue because of the unique challenges it poses in terms of complexity,safety and time,and also the lack of randomised controlled trials in this area.It is thus imperative that good quality multicentre randomised controlled trials are designed to investigate the benef its of extended lymphadenectomy in the setting of laparoscopic surgery,especially for advanced gastric cancer and its impact on both short and long term survival. 展开更多
关键词 GASTRECTOMY Meta-analysis RANDOMISED controlled trials LAPAROSCOPIC method Comparative studies RETROSPECTIVE trials Lympadenectomy Patient’s outcome
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Hepatitis B virus therapy:What's the future holding for us? 被引量:10
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作者 Sobia Manzoor Muhammad Saalim +2 位作者 Muhammad Imran Saleha Resham Javed ashraf 《World Journal of Gastroenterology》 SCIE CAS 2015年第44期12558-12575,共18页
Hepatitis B is one of the leading causes of liver cancer worldwide and unfortunately the number of people affected with hepatitis B virus(HBV) infection is still on the rise. Although the HBV has been known to cause f... Hepatitis B is one of the leading causes of liver cancer worldwide and unfortunately the number of people affected with hepatitis B virus(HBV) infection is still on the rise. Although the HBV has been known to cause fatal illness since decades but the population effected by this lethal virus have still only a few options for its management. The major treatment strategies include interferons and nucleos(t)ide analogues. These agents have so far produced unsatisfactory results in terms of complete virus eradication. Interferons cannot be used for long term therapy because of their potential side effects. Prolong treatment with nucleos(t)ide analogues has also been reported to cause serious side effects besides the increasing resistance by the virus. The need for new innovative solutions for treatment of HBV has been realized by global research institutes and pharmaceutical industry. Present review focuses in detail on the new ideas that are being transformed into therapeutic tools for use as future therapies in HBV infection. Modern drug designing and screening methods have made the drug discovery process shorter and more reliable. HBV therapeutics will take a new turn in coming years owing to these intelligent drug designing and screening methods. Future therapy of HBV is aiming to include the use of vaccines(both prophylactic and therapeutic), immunomodulators such as antibodies, non-nucleoside antivirals such as RNAi and inhibitors of viral life cycle. 展开更多
关键词 HEPATITIS B VIRUS treatment HEPATITIS B VIRUS vacc
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Effect of chromium on growth attributes in sunflower(Helianthus annuus L.) 被引量:9
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作者 FOZIA Andaleeb MUHAMMAD Anjum Zia +1 位作者 MUHAMMAD ashraf ZAFAR Mahmood Khalid 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第12期1475-1480,共6页
Heavy metal soil pollution takes place when the metal concentration of soil exceeds natural background level and causes ecological destruction and deterioration of the environment.In the present study,a pot experiment... Heavy metal soil pollution takes place when the metal concentration of soil exceeds natural background level and causes ecological destruction and deterioration of the environment.In the present study,a pot experiment was conducted to evaluate the effect of chromium-contaminated soil in sunflower(Helianthus annuus L.)growth attributes.Three different levels of chromium(Cr)i.e.,20, 40,and 60 mg/kg were applied to three varieties of sunflower(G-3,G-9,and G-59).The results of morphological,chemical,and yield p... 展开更多
关键词 Helianthus annuus L. SOIL CHROMIUM growth attributes
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Late Cretaceous biota and the Cretaceous-Paleogene(K--Pg)Boundary in Jiayin of Heilongjiang,China 被引量:9
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作者 Sun G. Akhmetiev M. +17 位作者 Markevich V. ashraf A. R. Bugdaeva E. Godefroit P. Bolotsky Yu. Dong Z. M. Golovneva L. Yang H. X. Sun C. L. Sun Y. W. Quan C. Kodrul T. Kezina T. Johnson K. Nishida H Dilcher D. L. Harding I. Chen Y. J. 《Global Geology》 2011年第3期115-143,共29页
An international cooperative study of the Late Cretaceous biota and non-marine strata including the Cretaceous-Paleogene(K--Pg) boundary in Jiayin near the Heilongjiang River,China during 2002-2010,is summarized in th... An international cooperative study of the Late Cretaceous biota and non-marine strata including the Cretaceous-Paleogene(K--Pg) boundary in Jiayin near the Heilongjiang River,China during 2002-2010,is summarized in this paper. The strata includes the Upper Cretaceous Yong'ancun-,Taipinglinchang-,Yuliang-zi-,and Furao formations,and the Paleocence Wuyun Formation consisting of Baoshantou Member and a Coalbearing Member. Seven palynological assemblages from Santonian to Paleocene are recognized,which is used for definition of the K--Pg boundary. Through the palynological analysis of three drilled boreholes (XHY-2005,2006,2008) in Xiaoheyan of western Jiayin,the K--Pg boundary is defined within 20. 00-20. 05 m in the borehole XHY-2006 (as a standard boundary) which is just between the top of Furao Formation (late Maasterichtian) and the base of Baishantou Member (early Danian) . These new research results are supported by paleo- magnetic,geochemical and other analyses,also. On the other hand,the presence of eight taxa of Maasterichtian dinosaurs (mostly hadrosaurids) have been recognized by the authors; and two mega-plant assemblages from the Yong'ancun Fm (Santonian) to Taipinglinchang Fm (Campanian) are confirmed. These research a-chievements indicate that the Upper Cretaceous-Paleocene in Jiayin can be well correlated to the strata in the neighboring Zeya-Bureja basin,Russia. The K--Pg boundary definited in Jiayin is the first well documented non-marine K--Pg boundary in China. Also the related paleoclimate,paleoenvironment and the mass extinctions in this area during the Cretaceous-Paleocene transition are also discussed. 展开更多
关键词 BIOTA Late Cretaceous PALEOGENE K-Pg boundary Heilongjiang River Jiayin
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