期刊文献+
共找到4,732篇文章
< 1 2 237 >
每页显示 20 50 100
Using Neural Networks to Predict Secondary Structure for Protein Folding 被引量:1
1
作者 Ali Abdulhafidh Ibrahim Ibrahim Sabah Yasseen 《Journal of Computer and Communications》 2017年第1期1-8,共8页
Protein Secondary Structure Prediction (PSSP) is considered as one of the major challenging tasks in bioinformatics, so many solutions have been proposed to solve that problem via trying to achieve more accurate predi... Protein Secondary Structure Prediction (PSSP) is considered as one of the major challenging tasks in bioinformatics, so many solutions have been proposed to solve that problem via trying to achieve more accurate prediction results. The goal of this paper is to develop and implement an intelligent based system to predict secondary structure of a protein from its primary amino acid sequence by using five models of Neural Network (NN). These models are Feed Forward Neural Network (FNN), Learning Vector Quantization (LVQ), Probabilistic Neural Network (PNN), Convolutional Neural Network (CNN), and CNN Fine Tuning for PSSP. To evaluate our approaches two datasets have been used. The first one contains 114 protein samples, and the second one contains 1845 protein samples. 展开更多
关键词 Protein Secondary Structure Prediction (PSSP) NeURAL NeTWORK (NN) Α-HeLIX (H) Β-SHeeT (e) coil (c) Feed Forward NeURAL NeTWORK (FNN) Learning Vector Quantization (LVQ) Probabilistic NeURAL NeTWORK (PNN) convolutional NeURAL NeTWORK (cNN)
下载PDF
Risk of connective—tissue disease in men with testicular or penile prostheses:a preliminary study
2
作者 KuJH SongYS 《Asian Journal of Andrology》 SCIE CAS CSCD 2002年第1期67-72,共6页
AIM: To help clarifying the possibility of connective-tissue diseases in men with penile or testicular prostheses. METHODS: Eight patients underwent inflatable penile prostheses and 15, testicular prostheses consented... AIM: To help clarifying the possibility of connective-tissue diseases in men with penile or testicular prostheses. METHODS: Eight patients underwent inflatable penile prostheses and 15, testicular prostheses consented to the study. Their medical records were reviewed and a follow-up interview and physical and serological examinations were performed. RESULTS: In patients with penile prostheses, there was no abnormal antinuclear antibody (ANA) or IgM elevation. The serum levels of the rheumatoid factor (RF), C4, IgA and IgG were abnormal in one patient, and the levels of erythrocyte sedimentation rate (ESR) and C3, abnormal in two. Four had elevated IgE. In patients with testicular prostheses, there was no abnormal RF, ANA or IgM. The serum levels of ESR and IgA were abnormal in two, and three had abnormal C4, ten abnormal C3, and eleven decreased IgG. All had increased IgE. Men with penile prostheses had higher serum levels of IgG and IgM than those with testicular prostheses (P=0.001, P=0.016, respectively). The rates of abnormal values of IgE and IgG were higher in men with testicular prostheses than in men with penile prostheses (P=0.008, P=0.009, respectively). Physical examination was normal in all patients and nobody had documented symptoms pertinent to connective-tissue diseases. CONCLUSION: Our findings suggest that the risk of connective-tissue diseases is not higher in patients wearing prostheses as the ANA is negative and there is no apparent manifestation suggestive of connective-tissue diseases. 展开更多
关键词 ADOLeSceNT Adult Aged Aged 80 and over Blood Sedimentation complement c3 complement c4 connective Tissue Diseases Humans Immunoglobulin A Immunoglobulin e Immunoglobulin G Immunoglobulin M Male Middle Aged Penile Prosthesis Pilot Projects Risk Factors Silicon
下载PDF
Hepatitis E virus chimeric DNA vaccine elicits immunologic response in mice 被引量:6
3
作者 Yan Hong Bing Ruan +4 位作者 Lian-Hua Yang Yong Chen Luo Jing Yi-Ting Wang Hua-Jun Hu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第42期6713-6715,共3页
AIM: To construct the plasmid pcHEV23 containing fragments of HEV ORF2 and ORF3 chimeric gene and to assess its ability to elicit specific immunologic response in mice. METHODS: The gene encoding the structural prot... AIM: To construct the plasmid pcHEV23 containing fragments of HEV ORF2 and ORF3 chimeric gene and to assess its ability to elicit specific immunologic response in mice. METHODS: The gene encoding the structural protein of HEV ORF2 fragment and full-length ORF3 was amplified by PCR. The PCR products were cloned into an eucaryotic expression plasmid pcDNA3. The resulting plasmid pcHEV23 was used as a DNA vaccine to inoculate BALB/c mice intramuscularly thrice at a dose of 100 or 200 ug. Mice injected with empty pcDNA3 DNA or saline served as control and then specific immune responses in the mice were detected. RESULTS: After 2-3 times of inoculation, all mice injected with pcHEV23 had anti-HEV IgG seroconversion and specific T lymphocyte proliferation. The lymphocyte stimulation index in the group immunized with pcHEV23 (3.1+0.49) was higher than that in the control group (0.787±0.12, P〈0.01). None in the control group had a detectable level of anti-HEV IgG. CONCLUSION: DNA vaccine containing HEV ORF2 and ORF3 chimeric gene can successfully induce specific humoral and cellular immune response in mice. 展开更多
关键词 Hepatitis e virus Animals Female Humans Lymphocyte Activation MIce Mice Inbred BALB c Open Reading Frames Plasmids Recombinant Fusion Proteins Research Support Non-U.S. Gov't T-LYMPHOcYTeS Vaccines DNA Viral Hepatitis Vaccines
下载PDF
Current perspectives of viral hepatitis 被引量:1
4
作者 Daisuke Usuda Yuki Kaneoka +23 位作者 Rikuo Ono Masashi Kato Yuto Sugawara Runa Shimizu Tomotari Inami Eri Nakajima Shiho Tsuge Riki Sakurai Kenji Kawai Shun Matsubara Risa Tanaka Makoto Suzuki Shintaro Shimozawa Yuta Hotchi Ippei Osugi Risa Katou Sakurako Ito Kentaro Mishima Akihiko Kondo Keiko Mizuno Hiroki Takami Takayuki Komatsu Tomohisa Nomura Manabu Sugita 《World Journal of Gastroenterology》 SCIE CAS 2024年第18期2402-2417,共16页
Viral hepatitis represents a major danger to public health,and is a globally leading cause of death.The five liver-specific viruses:Hepatitis A virus,hepatitis B virus,hepatitis C virus,hepatitis D virus,and hepatitis... Viral hepatitis represents a major danger to public health,and is a globally leading cause of death.The five liver-specific viruses:Hepatitis A virus,hepatitis B virus,hepatitis C virus,hepatitis D virus,and hepatitis E virus,each have their own unique epidemiology,structural biology,transmission,endemic patterns,risk of liver complications,and response to antiviral therapies.There remain few options for treatment,in spite of the increasing prevalence of viral-hepatitiscaused liver disease.Furthermore,chronic viral hepatitis is a leading worldwide cause of both liver-related morbidity and mortality,even though effective treatments are available that could reduce or prevent most patients’complications.In 2016,the World Health Organization released its plan to eliminate viral hepatitis as a public health threat by the year 2030,along with a discussion of current gaps and prospects for both regional and global eradication of viral hepatitis.Today,treatment is sufficiently able to prevent the disease from reaching advanced phases.However,future therapies must be extremely safe,and should ideally limit the period of treatment necessary.A better understanding of pathogenesis will prove beneficial in the development of potential treatment strategies targeting infections by viral hepatitis.This review aims to summarize the current state of knowledge on each type of viral hepatitis,together with major innovations. 展开更多
关键词 Hepatitis A virus Hepatitis B virus Hepatitis c virus Hepatitis D virus Hepatitis e virus current perspectives
下载PDF
On an Intriguing Invention Albert Einstein Made Which Has Gone Unnoticed Hitherto
5
作者 Jean-Paul Auffray 《Journal of Modern Physics》 2015年第11期1478-1491,共14页
We retrieve three mysterious sentences Albert Einstein wrote in the early years of his wondrous scientific career. We examine their implications and we suggest that they provide a surprising new basis for Quantum Phys... We retrieve three mysterious sentences Albert Einstein wrote in the early years of his wondrous scientific career. We examine their implications and we suggest that they provide a surprising new basis for Quantum Physics as well as some enlightenment concerning the whereabouts of Dark energy. 展开更多
关键词 eINSTeIN Absolute Measurements electromagnetic eNeRGY M = e/c2 Space Points Dark eNeRGY M. S. el Naschie Quantum MeTeORITeS
下载PDF
A Key Management Scheme for ZigBee in AMI of Smart Grid
6
作者 Jianquan Liang Xianji Jin +2 位作者 Shuidong Dai Weiming Tong Zhongwei Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第3期53-60,共8页
Advanced metering infrastructure( AMI) is a critical part of the smart grid,and ZigBee is playing an increasingly important role in AMI.The cyber security is the prerequisite to ensure the reliable operation of AMI.To... Advanced metering infrastructure( AMI) is a critical part of the smart grid,and ZigBee is playing an increasingly important role in AMI.The cyber security is the prerequisite to ensure the reliable operation of AMI.To guarantee the ZigBee communication security in AMI,a key management scheme based on the elliptic curve cryptosystem( ECC) is proposed.According to the ways of information transformation in AMI,the scheme is categorized as unicast communication key management process and multicast communication key management process.And in the scheme,the selection of elliptic curve,the calculation of ZigBee node's ECC public key and private key,the establishment and distribution of the link key in unicast communication,and the establishment and distribution of the network key in multicast communication are elaborated.The analysis results show that the proposed key management scheme is secure,and consumes less memory and energy,thus,can meet the demands of communication security of AMI. 展开更多
关键词 advanced MeTeRING INFRASTRUcTURe (A M I) ZIGBee key management eLLIPTIc cURVe cryptography(e c c ) smart grid
下载PDF
Oxidative stress modulation in hepatitis C virus infected cells 被引量:6
7
作者 Sonia A Lozano-Sepulveda Owen L Bryan-Marrugo +2 位作者 Carlos Cordova-Fletes Maria C Gutierrez-Ruiz Ana M Rivas-Estilla 《World Journal of Hepatology》 CAS 2015年第29期2880-2889,共10页
Hepatitis C virus(HCV) replication is associated with the endoplasmic reticulum, where the virus can induce cellular stress. Oxidative cell damage plays an important role in HCV physiopathology. Oxidative stress is tr... Hepatitis C virus(HCV) replication is associated with the endoplasmic reticulum, where the virus can induce cellular stress. Oxidative cell damage plays an important role in HCV physiopathology. Oxidative stress is triggered when the concentration of oxygen species in the extracellular or intracellular environment exceeds antioxidant defenses. Cells are protected and modulate oxidative stress through the interplay of intracellular antioxidant agents, mainly glutathione system(GSH) and thioredoxin; and antioxidant enzyme systems such as superoxide dismutase, catalase, GSH peroxidase, and heme oxygenase-1. Also, the use of natural and synthetic antioxidants(vitamin C and E, N-acetylcysteine, glycyrrhizin, polyenylphosphatidyl choline, mitoquinone, quercetin, S-adenosylmethionine and silymarin) has already shown promising results as co-adjuvants in HCV therapy. Despite all the available information, it is not known how different agents with antiviral activity can interfere with the modulation of the cell redox state induced by HCV and decrease viral replication. This review describes an evidence-based consensus on molecular mechanisms involved in HCV replication and their relationship with cell damage induced by oxidative stress generated by the virus itself and cell antiviral machinery. It also describes some molecules that modify the levels of oxidative stress in HCV-infected cells. 展开更多
关键词 Hepatitis c virus Oxidative stress Reactiveoxygen species VITAMIN e Antioxidants GLYcYRRHIZIN S-ADeNOSYLMeTHIONINe N-AceTYLcYSTeINe SILYMARIN
下载PDF
Assessment of antioxidant status of women with polycystic ovarian syndrome
8
作者 Olufisayo Grace Oyebanji Modupe Fisayo Asaolu 《Asian pacific Journal of Reproduction》 2020年第1期9-15,共7页
Objective:To determine the antioxidant status of females with polycystic ovarian syndrome.Methods:Blood samples of 85 females(45 newly diagnosed polycystic ovarian syndrome patients and 40 apparently healthy subjects)... Objective:To determine the antioxidant status of females with polycystic ovarian syndrome.Methods:Blood samples of 85 females(45 newly diagnosed polycystic ovarian syndrome patients and 40 apparently healthy subjects)between 25 and 45 years of age were obtained from Ekiti State University Teaching Hospital,Ado Ekiti,Ekiti State,Nigeria.Spectrophotometry was used to evaluate the plasma concentrations of malondialdehyde,vitamin A,C and E,reduced glutathione and activities of glutathione peroxidase,catalase and superoxide dismutase.Results:The concentrations of malondialdehyde and glutathione peroxidase activity significantly increased(P<0.05)in patients with polycystic ovarian syndrome compared with the healthy controls,while concentrations of reduced glutathione,vitamins A,C,E and activities of catalase and superoxide dismutase of patients with polycystic ovarian syndrome showed significant decrease(P<0.05)compared to the healthy controls.This study showed that oxidative stress may assume a role in the pathogenesis of polycystic ovarian syndrome.There were significant negative correlations between malondialdehyde and superoxide dismutase,catalase(P<0.01)and vitamin A(P<0.05),while there was a significant positive correlation(P<0.01)between malondialdehyde and glutathione peroxidase.In addition,vitamins A(P<0.05),C(P<0.01)and E(P<0.01)showed significant positive correlations with catalase antioxidant enzyme.However,vitamins C and E showed significant positive correlation(P<0.05)among each other.Conclusions:The involvement of antioxidants in the management of polycystic ovarian syndrome may be helpful as secondary therapy to prevent oxidative damage and may be used as a potential approach to overcome metabolic as well as reproductive disorders associated with infertility in polycystic ovarian syndrome. 展开更多
关键词 MALONDIALDeHYDe Reduced GLUTATHIONe Vitamin A c and e GLUTATHIONe peroxidase cATALASe Superoxide DISMUTASe POLYcYSTIc OVARY syndrome
下载PDF
在轴、外压联合作用下的C/E复合材料网格缠绕结构的开口补强设计 被引量:3
9
作者 提亚峰 张铎 +1 位作者 孙宏杰 董波 《宇航材料工艺》 CAS CSCD 北大核心 2010年第6期27-32,共6页
在复合材料网格结构临界轴、外压计算公式的基础上计算了C/E复合材料网格缠绕结构的整体承载能力,以无开口结构为目标,给出了补强设计方案。本文的研究结果,为复合材料壁板开口处结构的补强设计提供了可行方案,解决了工程中的实际问题。
关键词 联合作用 c/e复合材料 网格结构 缠绕结构 开口 补强设计 external Pressure AXIAL Force HOLe Structure 复合材料壁板 实际问题 设计方案 可行方案 计算公式 承载能力 目标 临界 结果 基础
下载PDF
Sperm quality improvement after natural anti-oxidant treatment of asthenoteratospermic men with leukocytospermia 被引量:8
10
作者 Paola Piomboni Laura Gambera +3 位作者 Francesca Serafini Giovanna Campanella Giuseppe Morgante Vincenzo De Leo 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第2期201-206,共6页
Aim: To study the immune-modulating and anti-oxidant effects of beta-glucan, papaya, lactoferrin, and vitamins C and E on sperm characteristics of patients with asthenoteratozoospermia associated with leucocytosis. M... Aim: To study the immune-modulating and anti-oxidant effects of beta-glucan, papaya, lactoferrin, and vitamins C and E on sperm characteristics of patients with asthenoteratozoospermia associated with leucocytosis. Methods: Fifty-one patients referred to our Sterility Center for semen analysis were selected. Sperm parameters were assessed before and after patient's treatment with beta-glucan, lactoferrin, papaya, and vitamins C and E. DNA damage was assessed by the acridine orange test and sperm structural characteristics were evaluated by transmission electron microscopy. Results: After 90 days of treatment, an increase in the percentage of morphologically normal sperm (17.0 ± 5.2 vs. 29.8 ± 6.5) and total progressive motility (19.0± 7.8 vs. 34.8 ± 6.8) were detected. Structural sperm characteristics as well as chromatin integrity were also improved after treatment. In terms of leukocyte concentration in seminal fluid, a significant reduction was recorded (2.2 ± 0.9 vs. 0.9± 0.2). Conclusion: The treatment of an inflammatory process by the synergic action of immune modulators and anti-oxidants could protect sperm during maturation and migration, leading to improved sperm function. (Asian JAndrol 2008 Mar;. 10: 201-206) 展开更多
关键词 asthenoteratozoospermia LeUKOcYTOSPeRMIA ANTI-OXIDANT BeTA-GLUcAN PAPAYA LAcTOFeRRIN vitamin c vitamin e chromatinintegrity transmission electron microscopy
下载PDF
Hepatitis B virus pre S1 deletion is related to viral replication increase and disease progression 被引量:5
11
作者 Seoung-Ae Lee Ki-Jeong Kim +3 位作者 Hong Kim Won-Hyuk Choi Yu-Sub Won Bum-Joon Kim 《World Journal of Gastroenterology》 SCIE CAS 2015年第16期5039-5048,共10页
AIM:To investigate the clinical implications of hepatitis B virus(HBV) pre S1 deletion.METHODS:We developed a fluorescence resonance energy transfer-based real-time polymerase chain reaction(RT-PCR) that can detect fo... AIM:To investigate the clinical implications of hepatitis B virus(HBV) pre S1 deletion.METHODS:We developed a fluorescence resonance energy transfer-based real-time polymerase chain reaction(RT-PCR) that can detect four genotypes(wild type, 15-bp, 18-bp and 21-bp deletion).The PCR method was used in two cohorts of Korean chronic HBV subjects with genotype C infections.Cohort Ⅰ included 292 chronic HBV subjects randomly selected from Cheju National University Hospital(Jeju, South Korea) or Seoul National University Hospital(Seoul, South Korea), and cohort Ⅱ included 90 consecutive chronic HBV carriers recruited from Konkuk University Hospital(Seoul, South Korea); the cohort Ⅱ patients did not have hepatocellular carcinoma or liver cirrhosis.RESULTS:The method proposed in this study identified 341 of 382 samples(89.3%).Deletion variants were identified in 100(29.3%) of the 341 detected samples.In both cohorts, the subjects with deletions had a significantly higher Hepatitis B virus e antigen(HBe Ag)-positive seroprevalence [cohort Ⅰ, wild(51.0%) vs deletion(75.0%), P < 0.001; cohort Ⅱ, wild(69.2%) vs deletion(92.9%), P = 0.002] and higher HBV DNA levels [cohort Ⅰ, wild(797.7 pg/m L) vs deletion(1678.9 pg/m L), P = 0.013; cohort Ⅱ, wild(8.3 × 108 copies/m L) vs deletion(2.2 × 109 copies/m L), P = 0.049], compared to subjects with wild type HBV.CONCLUSION:HBV genotype C pre S1 deletion may affect disease progression in chronic HBV subjects through an extended duration of HBe Ag seropositive status and increased HBV replications. 展开更多
关键词 HePATITIS B VIRUS PReS1 start cODON DeLeTION HePATITIS B VIRUS e ANTIGeN Hepatocellular carcinoma Genotype c
下载PDF
Interaction of methylenetetrahydrofolate reductase C677T,cytochrome P4502E1 polymorphism and environment factors in esophageal cancer in Kazakh population 被引量:13
12
作者 Jiang-Mei Qin Lei Yang Bo Chen Xiu-Mei Wang Feng Li Pei-Hua Liao Lin He 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第45期6986-6992,共7页
AIM: To evaluate the association and interaction of genetic polymorphisms in methylenetetrahydrofolate reductase (MTHER) and cytochrome P4502E1 (CY- P4502E1), environment risk factors with esophageal cancer (EC... AIM: To evaluate the association and interaction of genetic polymorphisms in methylenetetrahydrofolate reductase (MTHER) and cytochrome P4502E1 (CY- P4502E1), environment risk factors with esophageal cancer (EC) in Kazakh, a high EC incidence area of Xinjiang Uygur Autonomous Region, China. METHODS: A 1:2 matched case-control study was conducted with 120 cases of EC and 240 populationor hospital-based controls. The controls were matched for sex, nationality, area of residence and age within a 5-year difference. MTHER and CYP4502E1 genotypes were identified by PCR-based restriction fragment length polymorphism (RFLP). A conditional logistic regression model was established to identify risk factors. The strata method was adopted in interaction analysis. RESULTS: Low consumption of green vegetables and fresh fruits, alcohol drinking, and unsafe water (shallow well, or river) were found to be the risk factors for EC. Individuals with the MTHFR677 (C/T + T/T) genotype had a 2.62-fold (95% CI: 1.61-4.28) risk of developing EC compared with those who carried the C/C genotype. Individuals with the CYP4502EIC1/C1 genotype had a 3.00-fold (95% CI: 1.82-4.96) risk compared with those who carried the CYP4502E1 (C1/C2 + C2/C2) genotype. Gene-environment interaction analysis showed that MTHFR677 gene polymorphism was correlated with consumption of green vegetables and fresh fruit, while CYP4502E1 C1/C1 was correlated with alcohol drinking and unsafe drinking water. MTHFR and CYP4502E1 analysis of gene-gene interaction showed that individuals with the MTHFR677 (C/T + T/T) and CYP4502EIC1/ C1 genotypes had a 7.41-fold (95% CI: 3.60-15.25) risk of developing EC compared with those who carried the MTHFR677C/C and CYP4502E1 RsaI C1/C2 + C2/C2 genes, and the interaction rate was higher than that of the two factors alone. CONCLUSION: Low consumption of green vegetables and fresh fruits, alcohol drinking, and unsafe water (shallow well, or river) and polymorphisms in MTHFR and CYP4502E1 genes are important risk factors for EC. There is a synergistic interaction among polymorphisms in MTHFR and CYP4502E1 genes and environment factors. MTHFR and CYP4502E1 genes can be used as biomarkers for prevention of EC in Kazakh, Xinjiang Uygur Autonomous Region, China. 展开更多
关键词 KAZAKH esophageal cancer Methylenetet-rahydrofolate reductase c677T cytochrome P4502e1 Genetic polymorphism environment risk factors INTeRAcTION case control study
下载PDF
An Analysis of Problematic C-E Translations of Signs in Light of Nida's Functional Equivalence Theory
13
作者 唐芳 《海外英语》 2015年第11期135-138,共4页
Based on Nida’s Functional Equivalence theory,this article makes an analysis of the problems in C-E translations ofsigns in China.The author will discuss respectively the problematic C-E translations from two respect... Based on Nida’s Functional Equivalence theory,this article makes an analysis of the problems in C-E translations ofsigns in China.The author will discuss respectively the problematic C-E translations from two respects:1)not being equivalent tosource-language message,and 2)not being natural for target language.If translators work hard with the help of Nida’s functionalequivalence theory,the defects and imperfections will be discovered,and standard signs in English will be read more and more inpublic places. 展开更多
关键词 Nida’s functional equivalence theory PROBLeMATIc c-e TRANSLATIONS SIGNS source-language message target language
下载PDF
Effects of enzymatic and non-enzymatic antioxidants in diluents on cryopreserved bull epididymal sperm
14
作者 Hasan Sakhdary Abbas Farshad +2 位作者 Jalal Rostamzadeh Fateme Bahri Binabaj Keyvan Sobhani 《Asian pacific Journal of Reproduction》 2022年第1期44-50,共7页
Objective:To evaluate the supplementation effects of vitamin E,vitamin C,superoxide dismutase(SOD),and catalase to diluents on bull cryopreserved epididymal sperm.Methods:Sperm were retrieved from 20 bull testes and w... Objective:To evaluate the supplementation effects of vitamin E,vitamin C,superoxide dismutase(SOD),and catalase to diluents on bull cryopreserved epididymal sperm.Methods:Sperm were retrieved from 20 bull testes and were then supplemented with 0.1 mM vitamin E,5.0 mM vitamin C,100.0 IU/mL SOD,and 100.0μg/mL catalase alone,or in a combination.The control treatment contained no addition.After supplementation,samples were frozen and stored in liquid nitrogen.The sperm parameters including motility,progressive motility,viability,acrosome integrity,plasma membrane integrity,kinematics and DNA damage were evaluated following the thawing process.Results:Vitamin E alone significantly increased the parameters of acrosome and membrane integrity compared to the control treatment(P<0.05).While compared to the control treatment,vitamin C had no improvement effect on sperm characteristics except for membrane integrity.Treatment of vitamin E+vitamin C had a significant improvement in total motility,progressive motility,viability,membrane and acrosome integrity compared to the control and other treatments(P<0.05).Compared to the control treatment,addition of SOD or catalase alone significantly improved the percentages of total motility,progressive motility,viability,membrane and acrosome integrity(P<0.05).Furthermore,SOD+catalase significantly increased total motility,progressive motility,viability,acrosome and membrane integrity characteristics compared to the catalase treatment(P<0.05).Vitamin E alone,vitamin E+vitamin C,and SOD in diluents decreased DNA damages and thereby improved the rate of intact sperm heads.Conclusions:Addition of 100.0 IU/mL SOD alone and 0.1 mM vitamin E+5.0 mM vitamin C,and also 5.0 mM vitamin C+100μg/mL catalase in a combination improves the quality of cryopreserved bull epididymal sperm and could be used for cryopreservation. 展开更多
关键词 Antioxidant cRYOPReSeRVATION Spermatological characteristics DNA damage BULL Vitamin e Vitamin c Superoxide dismutase cATALASe Oxidative stress
下载PDF
Melatonin reduces traumatic brain injury-induced oxidative stress in the cerebral cortex and blood of rats 被引量:5
15
作者 Nilgün Senol Mustafa Naziroglu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第11期1112-1116,共5页
Free radicals induced by traumatic brain injury have deleterious effects on the function and antioxidant vitamin levels of several organ systems including the brain. Melatonin possesses antioxidant effect on the brain... Free radicals induced by traumatic brain injury have deleterious effects on the function and antioxidant vitamin levels of several organ systems including the brain. Melatonin possesses antioxidant effect on the brain by maintaining antioxidant enzyme and vitamin levels. We in-vestigated the effects of melatonin on antioxidant ability in the cerebral cortex and blood of traumatic brain injury rats. Results showed that the cerebral cortex β-carotene, vitamin C, vita-min E, reduced glutathione, and erythrocyte reduced glutathione levels, and plasma vitamin C level were decreased by traumatic brain injury whereas they were increased following melatonin treatment. In conclusion, melatonin seems to have protective effects on traumatic brain inju-ry-induced cerebral cortex and blood toxicity by inhibiting free radical formation and supporting antioxidant vitamin redox system. 展开更多
关键词 nerve regeneration MeLATONIN traumatic brain injury ANTIOXIDANT oxidative stress vitamin e vitamin c GLUTATHIONe brain neural regeneration
下载PDF
The Scientific Revolution in Power Plants
16
作者 Mohamed Hyder Seid-Ahmed Elfaki 《Smart Grid and Renewable Energy》 2012年第2期96-103,共8页
It has been made a proposal of new ideal cycle for power plants which is working by a turbine gas, for both closed and open systems. It has been designed a special device for adding heat at constant volume. The aim of... It has been made a proposal of new ideal cycle for power plants which is working by a turbine gas, for both closed and open systems. It has been designed a special device for adding heat at constant volume. The aim of special device is to decrease the amount of added heat for the new cycle. We have made a comparison between the simple gas turbine cycle & the new cycle. The results has been shown, that the efficiency of new cycle is greater than the simple cycle of gas turbine. 展开更多
关键词 I c (Internal combustion) e.c (external combustion) S.c (Simple Gas TURBINe cycle) N.c (New cycle)
下载PDF
Differential expression of cell cycle regulators in HCV-infection and related hepatocellular carcinoma 被引量:3
17
作者 Azza E El Bassiouny Mona M Nosseir +6 位作者 Mona K Zoheiry Noha A Ameen Ahmed M Abdel-Hadi Ibrahim M Ibrahim Suher Zada Abdel-Hakeem Saad El-Deen Nora E El-Bassiouni 《World Journal of Hepatology》 CAS 2010年第1期32-41,共10页
AIM:To investigate cell cycle proteins in chronic hepatitis C virus infection in order to analyze their role in the process of hepatocyte transformation and to characterize their prognostic properties. METHODS:Subject... AIM:To investigate cell cycle proteins in chronic hepatitis C virus infection in order to analyze their role in the process of hepatocyte transformation and to characterize their prognostic properties. METHODS:Subjects of the current study included 50 cases of chronic hepatitis C(CHC) without cirrhosis,30 cases of CHC with liver cirrhosis(LC) ,and 30 cases of hepatitis C-related hepatocellular carcinoma(HCC) admitted to the Department of Hepato-Gastroenterology,Theodor Bilharz Research Institute(TBRI) ,Giza,Egypt.Fifteen wedge liver biopsies,taken during laparoscopic cholecystectomy,were also included as normal controls.Laboratory investigations including urine and stool analysis,liver function tests and prothrombin concentration;serologic markers for viral hepatitis and ultrasonography were done for all cases of the study together with immunohistochemical analysis using primary antibodies against Cyclin D1,Cyclin E,p21,p27 and Rb/p105 proteins. RESULTS:Normal wedge liver biopsies didn't express Cyclin E or Rb/p105 immunostaining but show positive staining for Cyclin D1,p21 and p27.Cyclin D1 expressed nuclear staining that was sequentially increased from CHC to LC(P<0.01) to HCC(P<0.001) cases;meanwhile,Cyclin E revealed nuclear positivity only in the case of HCCs patients that was directly correlated to Rb/p105 immuno-reactivity.The expression of p21 and p27 was significantly increased in CHC and LC cases compared to normal controls and HCCs with no significant difference between well-and poorlydifferentiated tumors.p21 showed only a nuclear pattern of staining,while,p27 presented with either cytoplasmic and/or nuclear reactivity in all studied cases.Correlation analysis revealed a direct relation between Cyclin D1 and p21 in CHC cases(P<0.001) ,between Cyclin D1 and Cyclin E in HCCs(P<0.01);however,an inverserelationship was detected between Cyclin D1 and p21 or p27(P<0.001) and between p21 and Rb/p105(P<0.05) in HCCs. CONCLUSION:Upregulation of Cyclin D1 in CHC plays a vital role in the development and differentiation of HCC;while,Cyclin E may be a useful marker for monitoring tumor behavior.p21 and p27 can be used as predictive markers for HCC.Furthermore,higher expression of Rb/p105 as well as inverse relation with p21 and histologic grades suggests its important role in hepatic carcinogenesis. 展开更多
关键词 chronic HePATITIS c Liver cIRRHOSIS HePATOceLLULAR carcinoma cell cycle cYcLIN D1 cYcLIN e p21 P27 Rb/p105
下载PDF
From hepatitis A to E:A critical review of viral hepatitis 被引量:5
18
作者 Daniel Castaneda Adalberto Jose Gonzalez +2 位作者 Mohammad Alomari Kanwarpreet Tandon Xaralambos Bobby Zervos 《World Journal of Gastroenterology》 SCIE CAS 2021年第16期1691-1715,共25页
Viral infections affecting the liver have had an important impact on humanity,as they have led to significant morbidity and mortality in patients with acute and chronic infections.Once an unknown etiology,the discover... Viral infections affecting the liver have had an important impact on humanity,as they have led to significant morbidity and mortality in patients with acute and chronic infections.Once an unknown etiology,the discovery of the viral agents triggered interest of the scientific community to establish the pathogenesis and diagnostic modalities to identify the affected population.With the rapid scientific and technological advances in the last centuries,controlling and even curing the infections became a possibility,with a large focus on preventive medicine through vaccination.Hence,a comprehensive understanding of hepatitis A,B,C,D and E is required by primary care physicians and gastroenterologists to provide care to these patients.The review article describes the epidemiology,pathogenesis,clinical presentation,diagnostic tools and current medication regimens,with a focus on upcoming treatment options and the role of liver transplantation. 展开更多
关键词 Hepatitis A Hepatitis B Hepatitis c Hepatitis D Hepatitis e TReATMeNT
下载PDF
Viral hepatitis update: Progress and perspectives 被引量:17
19
作者 María B Pisano Cecilia G Giadans +3 位作者 Diego M Flichman Viviana E Ré María V Preciado Pamela Valva 《World Journal of Gastroenterology》 SCIE CAS 2021年第26期4018-4044,共27页
Viral hepatitis,secondary to infection with hepatitis A,B,C,D,and E viruses,are a major public health problem and an important cause of morbidity and mortality.Despite the huge medical advances achieved in recent year... Viral hepatitis,secondary to infection with hepatitis A,B,C,D,and E viruses,are a major public health problem and an important cause of morbidity and mortality.Despite the huge medical advances achieved in recent years,there are still points of conflict concerning the pathogenesis,immune response,development of new and more effective vaccines,therapies,and treatment.This review focuses on the most important research topics that deal with issues that are currently being solved,those that remain to be solved,and future research directions.For hepatitis A virus we will address epidemiology,molecular surveillance,new susceptible populations as well as environmental and food detections.In the case of hepatitis B virus,we will discuss host factors related to disease,diagnosis,therapy,and vaccine improvement.On hepatitis C virus,we will focus on pathogenesis,immune response,direct action antivirals treatment in the context of solid organ transplantation,issues related to hepatocellular carcinoma development,direct action antivirals resistance due to selection of resistanceassociated variants,and vaccination.Regarding hepatitis D virus,we describe diagnostic methodology,pathogenesis,and therapy.Finally,for hepatitis E virus,we will address epidemiology(including new emerging species),diagnosis,clinical aspects,treatment,the development of a vaccine,and environmental surveillance. 展开更多
关键词 Viral hepatitis Hepatitis A virus Hepatitis B virus Hepatitis c virus Hepatitis D virus Hepatitis e virus
下载PDF
The effects of large doses of vitamin C and vitamin E on nerve injury, neurotrophic and oxidative stress in patients with acute craniocerebral injury 被引量:4
20
作者 Cheng Zhang Jian-Ming Li +1 位作者 Jun-Lin Hu Xia Zhou 《Journal of Acute Disease》 2018年第2期69-73,共5页
Objective:To study the effects of large doses of vitamin C and vitamin E on nerve injury,neurotrophic and oxidative stress in patients with acute craniocercbral injury.Methods:Patients with acute cranioccrebral trauma... Objective:To study the effects of large doses of vitamin C and vitamin E on nerve injury,neurotrophic and oxidative stress in patients with acute craniocercbral injury.Methods:Patients with acute cranioccrebral trauma who were admitted to the Third People's Hospital of Zigong from April 2014 to December 2016 were selected as the subjects and were randomly divided into two groups.The control group received conventional treatment,and the intervention group received large doses of vitamin C and vitamin E combined with conventional treatment.On the yh day and 7th day after treatment,peripheral blood was collected and serum was isolated,then the contents of nerve injury index NSE,S 100B,NGB,UCH-L1,Tf,Ft and neurotrophic indexes NTF-α,BDNE NGF and IGF-I were determined by Enzyme-linked immunosorbent assay kit,and the contents of SOD,GPx,CAT,OH-,O2,MDA and AOPP were measured by radioactive immunoprecipitation kit.Results:3th day and 7th day after treatment,the contents of NSE,S100B,NGB,UCH-L1,Tf,Ft,NTF-α,BDNF,NGF,IGF-Ⅰ,OH-,O2-,MDA and AOPP in the intervention group were all significantly lower than those in the control group.The content of SOD,GPx and CAT in serum in the intervention group was significantly higher than that in the control group.Conclusions:High-dose vitamin C and vitamin E treatment can alleviate nerve injury,oxidative stress response,and improve neurotrophic state in patients with acute craniocerebral injury. 展开更多
关键词 Acute cRANIOceReBRAL injury OXIDATIVe stress VITAMIN c VITAMIN e NeUROTROPHY
下载PDF
上一页 1 2 237 下一页 到第
使用帮助 返回顶部