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Ultra-soft Desorption Assisted Mass Spectrometry using Picosecond Infrared Laser for the Detection of lons in the Liquid Surface
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作者 Ziyuan Li Yue Wang +2 位作者 Tiantian Tong Ziwei Chen Shan Xi Tian 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期461-464,I0093,共5页
To identify the species in liquid surface using mass spectrometry,we must eliminate or reduce interferences during the vaporization or desorption of the species from the liquid surface.It is much more challenging to i... To identify the species in liquid surface using mass spectrometry,we must eliminate or reduce interferences during the vaporization or desorption of the species from the liquid surface.It is much more challenging to isolate the ionic,larger species from the liquid surface,because of the frangible structures and the higher solvation energies of those species.Here we demonstrate a new mass spectrometry in which the ionic species at the liquid surface can be desorbed with ultrasoft infrared picosecond laser pulses while the liquid surface is not breached.This laser desorption assisted mass spectrometry is not only a powerful tool to detect the fragile species but also promising to investigate vibrational energy transfer dynamics in the liquid surface. 展开更多
关键词 Ultrasoft desorption Infrared laser Picosecond pulse Mass spectrometry Liquid surface
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Integration of Lab model and EHOG for human appearance matching across disjoint camera views 被引量:2
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作者 杨彪 林国余 张为公 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期422-427,共6页
The integration of the Lab model with the extended histogram of oriented gradients (EHOG) is proposed to improve the accuracy of human appearance matching across disjoint camera views under perturbations such as ill... The integration of the Lab model with the extended histogram of oriented gradients (EHOG) is proposed to improve the accuracy of human appearance matching across disjoint camera views under perturbations such as illumination changes and different viewing angles. For the Lab model that describes the global information of observations, a sorted nearest neighbor clustering method is proposed for color clustering and then a partitioned color matching method is used to calculate the color similarity between observations. The Bhattacharya distance is employed for the textural similarity calculation of the EHOG which describes the local information. The global information, which is robust to different viewing angles and scale changes, describes the observations well. Meanwhile, the use of local information, which is robust to illumination changes, can strengthen the discriminative ability of the method. The integration of global and local information improves the accuracy and robustness of the proposed matching approach. Experiments are carried out indoors, and the results show a high matching accuracy of the proposed method. 展开更多
关键词 human appearance matching Lab model extended histogram of oriented gradients (EHOG) disjoint camera views
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Comparison between Infrared and Microwave Radiometers for Retrieving Sea Surface Temperature 被引量:1
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作者 殷晓斌 王振占 +3 位作者 刘玉光 程永存 顾艳振 文凡 《Marine Science Bulletin》 CAS 2009年第2期1-12,共12页
The basic principles of sea surface temperature (SST) remote sensing using infrared and microwave radiometers are introduced, and the differences between two sensors for retrieving sea surface temperature are invest... The basic principles of sea surface temperature (SST) remote sensing using infrared and microwave radiometers are introduced, and the differences between two sensors for retrieving sea surface temperature are investigated. The ground resolution, atmospheric effect, sea surface wind, skin depth and so on have important influence on precision of sea surface temperature retrieved by two sensors. The better understanding of the advantage and disadvantage of sea surface temperature detected by infrared and microwave radiometers would help us to imply SST remote sensing data more effectively and correctly. 展开更多
关键词 INFRARED MICROWAVE RADIOMETER sea surface temperature
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Selective Area Growth InGaAsP by MOVPE
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作者 邱伟彬 董杰 +1 位作者 王圩 周帆 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第4期342-346,共5页
The wide stripe (15μm) selective area growth (SAG) of InGaAsP by low pressure MOVPE is systematically investigated.The characteristics of the growth ratios,thickness enhancement factors,bandgap modulation,and composi... The wide stripe (15μm) selective area growth (SAG) of InGaAsP by low pressure MOVPE is systematically investigated.The characteristics of the growth ratios,thickness enhancement factors,bandgap modulation,and composition modulation vary with the growth conditions such as mask width,growth pressure.Flux of Ⅲ group precursors are outlined and the rational mechanism behind SAG MOVPE is explained.In addition,the surface spike of the SAG InGaAsP is shown and the course of it is given by the variation of Ⅴ/Ⅲ. 展开更多
关键词 SAG MOVPE INGAASP edge spike Ⅴ/Ⅲ ratio
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Genes Expression Profile Difference in Peripheral Blood Between Esophageal Carcinoma Patients and Normal Subjects 被引量:1
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作者 钱丽娟 许沈华 +3 位作者 牟瀚舟 冯建国 朱赤红 刘祥麟 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第5期279-283,324,共6页
Objective: To study the genes expression profile differences in the peripheral blood between esophageal carcinoma patients and normal subjects using the gene chip technique and screen out the esophageal early concera... Objective: To study the genes expression profile differences in the peripheral blood between esophageal carcinoma patients and normal subjects using the gene chip technique and screen out the esophageal early conceration associated genes. Methods: The total RNA was extracted and purified in the peripheral blood obtained from the patients with esophageal carcinoma and normal subjects. The first strand of cDNA was synthesized through retro-transcription and labeled with Cy5 and Cy3 fluorescence as probes. The mixed probes were hybridized with a piece of 4096 double dot human whole gene chip. The acquired image was analyzed by microarrav suite software using a digital computer, and the intensity of ttuorescence signal and its ratio were calculated. Results: A total of 92 genes were screened out and its expression difference was more than 2 times in the peripheral blood between the patients with esophageal carcinoma and normal subjects. Among these, the expression difference of 36 genes was more than 3 times. Two human urokinase plasminogen activator surface receptor (UPAR) genes, 80K-L protein gene, human protein tyrosine-phosphatase gent arid proto-oncogene protein mRNA were significantly up-regulated, while the collagen V type (α-2 gene was markedly down-regulated. Conclusion: 80K-L protein gene, tyrosinephophatase gene, proto-oncogene protein arid the collagen V type α-2 gene might be associated with the ontogenesis, development and its metastasis in the esophageal carcinoma. The UPAR gene may play important roles in the diagnosing the micrometastasis in the peripheral blood of esophageal carcinoma. 展开更多
关键词 human esophageal carcinoma: peripheral blood gene expression profile
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牢固树立新课程理念 多渠道提高思想品德教学效果
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作者 刘茂香 《跨世纪》 2008年第9期178-178,共1页
世界是一个旋转的舞台,思想品德植根于社会这个大舞台,教师要利用各种课程资源,调动各种有利因素,向各方位延伸,使自身和学生在这个自由旋转的舞台中体验、发展、表现、完善自我,从而通过互动教学模式,达到优化教学效果的目的。
关键词 教学效果 教学方法多样化 社会实践活动 拓宽教学空间 “外表”
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Prokaryotic Expression and Identification of Outer Membrane Protein 2 of Chlamydia trachomatis
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作者 陈超群 吴移谋 +2 位作者 李忠玉 朱翠明 尹卫国 《Chinese Journal of Sexually Transmitted Infections》 2004年第2期67-71,i001,共6页
Objective: To construct a recombinant plasmid containing the outer membrane protein 2 (Omp2) gene of Chlamydia trachomatis and express Omp2 in E.coli. Methods: The omp2 gene of C. trachomatis serovar D was cloned into... Objective: To construct a recombinant plasmid containing the outer membrane protein 2 (Omp2) gene of Chlamydia trachomatis and express Omp2 in E.coli. Methods: The omp2 gene of C. trachomatis serovar D was cloned into pQE30 vector following PCR amplification from genomic DNA. E. coli M15 transformants were induced to express the fusion protein by IPTG and the product was identified by SDS-PAGE and Western blot. Results: Confirmed by enzyme cleavage analysis and DNA sequencing, a correct recombinant plasmid pQE30/omp2 was constructed. The fusion protein from the transformants was approximately 60 kDa in size in SDS-PAGE analysis, which could specially react with anti-6 X His mouse monoclonal IgG antibodies. Conclusion: We successfully expressed Omp2 in E. coli M15, providing an efficient and simple system for assaying the immunological properties of Omp2. 展开更多
关键词 Chlamydia trachomatis outer membrane protein 2(omp2) expression.
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Existence of Extracellular Calmodulin in the Lower Epidermis of the Leaves of Vicia faba and Its Role in Regulating Stomatal Movements
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作者 陈玉玲 张学琴 +1 位作者 陈珈 王学臣 《Acta Botanica Sinica》 CSCD 2003年第1期40-46,共7页
As a possible peptide primary messenger, extracellular calmodulin (CaM) may regulate processes such as cell proliferation, pollen germination and expression of some genes. Stomata open or close quickly in response to ... As a possible peptide primary messenger, extracellular calmodulin (CaM) may regulate processes such as cell proliferation, pollen germination and expression of some genes. Stomata open or close quickly in response to environmental stimuli. CaM was found to be extracellular both in guard cells of broad bean leaves and in epidermal cells by immuno-electron microscopy and immuno-fluorescence microscopy techniques. Exogenous purified CaM enhanced stomatal closure and inhibited stomatal opening with an optimal concentration of 10(-8) mol/L; CaM antagonist W7-agarose and anti-CaM serum, which were membrane-impermeable macromolecules, inhibited stomatal closure and promoted stomatal opening. All these data showed that endogenous extracellular CaM. of guard cells did promote stomatal closure and inhibit stomatal opening, and could he active only outside the cells. Therefore under natural conditions, the endogenous extracellular CaM of guard cells might regulate stomatal movements as a primary messenger together with other signal molecules, and might be an important linkage between environmental stimuli and cell responses. 展开更多
关键词 extracellular CaM Vicia faba stomatal movement
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Alterations of seminal and hormonal parameters:An extrahepatic manifestation of HCV infection? 被引量:9
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作者 Marilena Durazzo Alberto Premoli +6 位作者 Cataldo Di Bisceglie Angela Bertagna Emanuela Fagà Giampaolo Biroli Chiara Manieri Simona Bo Gianfranco Pagano 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第19期3073-3076,共4页
AIM: To evaluate the possible influences of HCV infection and relative antiviral treatment on seminal parameters and reproductive hormonal serum levels. METHODS: Ten male patients with HCV-related chronic hepatitis ... AIM: To evaluate the possible influences of HCV infection and relative antiviral treatment on seminal parameters and reproductive hormonal serum levels. METHODS: Ten male patients with HCV-related chronic hepatitis and 16 healthy male volunteers were studied. In all subjects seminal parameters (nemaspermic concentration, progressive motility, morphology) and hormonal levels were determined. Seminal parameters and inhibin B, follicle-stimulating hormone, luteinizing hormone, total and free testosterone, estradiol, prolactine in patients were measured after six and twelve months of antiviral combined (interferon ± ribavirin) treatment. RESULTS: Patients before treatment showed a significantly lower nemaspermic motility and morphology as well as lower inhibin B and free testosterone levels than controls. Inhibin B levels in cases were improved six and 12 mo after treatment in five responders (161.9 ± 52.8 pg/mL versus 101.7 ± 47.0 pg/mL and 143.4 ± 46.1 pg/ mL versus 95.4 ± 55.6 pg/mL, respectively). Hormonal pattern of patients did not significantly change after treatment, with the exception of estradiol levels with an initial reduction and an overall subsequent increment (19.7 ± 6.4 pg/mL versus 13.6 ± 5.0 pg/mL versus 17.3 ± 5.7 pg/mL). However in 1-year responders a significant increment of free testosterone (14.2 ± 2.54 pg/mL versus 17.1 ± 2.58 pg/mL) occurred. An impairment of nemaspermic morphology occurred, while other seminal parameters did not change significantly during antiviral treatment. CONCLUSION: Patients with HCV infection show worse spermatic parameters than controls, suggesting a possible negative influence of virus on spermatogenesis, with further mild impairment during antiviral treatment. However therapy could improve the spermatic function, as suggested by the increased inhibin B levels and improved hormonal pattern in responders. Further studies are needed to confirm these preliminary intriguing results. 展开更多
关键词 HCV hepatitis Seminal parameters Antiviral treatment Extrahepatic manifestations
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Extraintestinal manifestations of inflammatory bowel disease:Do they influence treatment and outcome? 被引量:16
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作者 Fernando Tavarela Veloso 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第22期2702-2707,共6页
Crohn's disease and ulcerative colitis are chronic inflammatory bowel diseases that often involve organs other than those of the gastrointestinal tract. Immune-related extraintestinal manifestations (EIMs) are usu... Crohn's disease and ulcerative colitis are chronic inflammatory bowel diseases that often involve organs other than those of the gastrointestinal tract. Immune-related extraintestinal manifestations (EIMs) are usually related to disease activity, but sometimes may take an independent course. Globally, about one third of patients develop these systemic manifestations. Phenotypic classification shows that certain subsets of patients are more susceptible to developing EIMs, which frequently occur simultaneously in the same patient overlapping joints, skin, mouth, and eyes. The clinical spectrum of these manifestations varies from mild transitory to very severe lesions, sometimes more incapacitating than the intestinal disease itself. The great majority of these EIMs accompany the activity of intestinal disease and patients run a higher risk of a severe clinical course. For most of the inflammatory EIMs, the primary therapeutic target remains the bowel. Early aggressive therapy can minimize severe complications and maintenance treatment has the potential to prevent some devastating consequences. 展开更多
关键词 Inflammatory bowel disease Immune-related extraintestinal manifestations TREATMENT
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Hepatitis C virus-related lymphoproliferative disorders:An overview 被引量:5
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作者 Anna Linda Zignego Carlo Giannini Clodoveo Ferri 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第17期2467-2478,共12页
Hepatitis C virus (HCV) is a global health problem affecting 3% of the world's population (about 180 million) and a cause of both hepatic and extrahepatic diseases. B-cell lymphoproUferative disorders, whose prot... Hepatitis C virus (HCV) is a global health problem affecting 3% of the world's population (about 180 million) and a cause of both hepatic and extrahepatic diseases. B-cell lymphoproUferative disorders, whose prototype is mixed cryoglobulinemia, represent the most closely related as well as the most investigated HCV- related extrahepatic disorder. The association between extrahepatic (lymphoma) as well as hepatic malignancies (hepatocellular carcinoma) has justified the inclusion of HCV among human cancer viruses. HCV-associated manifestations also include porphyria cutanea tarda, lichen planus, nephropathies, thyreopathies, sicca syndrome, idiopathic pulmonary fibrosis, diabetes, chronic polyarthritis, sexual dysfunctions, cardiopathy/ atherosclerosis, and psychopathological disorders. A pathogenetic link between HCV virus and some lymphoproliferative disorders was confirmed by their responsiveness to antiviral therapy, which is now considered the first choice treatment. The aim of the present paper is to provide an overview of extrahepatic manifestations of HCV infection with particular attention to B-cell lymphoproliferative disorders. Available pathogenetic hypotheses and suggestions about the most appropriate, currently available, therapeutic approaches will also be discussed. 展开更多
关键词 Hepatitis C virus Extrahepatic manifestations Lymphoproliferative disorders Mixed cryoglobulinemia LYMPHOMA
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Changes of ECM and CAM gene expression profile in the cirrhotic liver after HCV infection: Analysis by cDNA expression array 被引量:2
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作者 XinXu Yi-MingLi +3 位作者 HongJi Chong-ZhiHou Ying-BoCheng Fu-PingMa 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第14期2184-2187,共4页
AIM: We aimed to observe the expression of extracellular matrix (ECM) and cellular adhesion molecules (CAM) in cirrhotic liver tissues after hepatitis C virus (HCV) infection. METHODS: Twelve patients with post HCV in... AIM: We aimed to observe the expression of extracellular matrix (ECM) and cellular adhesion molecules (CAM) in cirrhotic liver tissues after hepatitis C virus (HCV) infection. METHODS: Twelve patients with post HCV inflammatory liver cirrhosis were selected to evaluate their liver function and other virological, pathological parameters. Then three specimens of cirrhotic patients whose health assessment results and laboratory data were similar and three normal liver specimens explanted from liver grafts prepared for liver transplantation were chosen for investigating gene expression of ECM and CAM using cDNA expression array. RESULTS: The cDNA array assay revealed 36.7% (36/96)of genes with changes, in which 26.3% (26/96) was up regulated and 10.1% (10/96) was down-regulated. Integrin (ITGA), collagen (COL), ADAMTS were identified as the characteristic changes of ECM and CAM gene expression levels. ITGA were demonstrated β1 and β2 sub-section changed in liver cirrhosis.CONCLUSION: ECM and CAM play an important role inthe progression of liver cirrhosis after HCV infection. The capital mechanism is related to the inflammatory cellsinfiltration, the activation and transformation of ECM producing cells and the imbalance between production and elimination of ECM. 展开更多
关键词 Hepatitis C virus Liver cirrhosis Extracellular matrix Cellular adhesion molecules mRNA array analysis
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Analytic computation on the forcible thawing temperature field formed by a single heat transfer pipe with unsteady outer surface temperature 被引量:3
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《Journal of Coal Science & Engineering(China)》 2012年第1期18-24,共7页
A comprehensive and systematic research on the forcible thawing temperature field formed by a single heat transfer pipe with unsteady outer surface temperature was carried out by analytic computation according to the ... A comprehensive and systematic research on the forcible thawing temperature field formed by a single heat transfer pipe with unsteady outer surface temperature was carried out by analytic computation according to the theory of similitude. The distribution law of thawing temperature field, calculation formulas of thawing radius b, heat flux density q and average thawing temperature T were obtained. It theoretically explains that the main influential factors of thawing radius b, heat flux density q and thawing average temperature T are K,f, Lx and co(l), but Lc affects little. Finally, based on the forcible thawing project of Hulusu air shaft lining, the field data indicate that the analytical formulas of this article are comparatively accurate. 展开更多
关键词 analytic computation forcible thawing temperature field theory of similitude artificial ground freezing
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Low-cost synthesis of nanoaggregate SAPO-34 and its application in the catalytic alcoholysis of furfuryl alcohol 被引量:3
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作者 Qianqian Guo Fan Yang +3 位作者 Xiaohui Liu Mengqing Sun Yong Guo Yanqin Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第11期1772-1781,共10页
Silicoaluminophosphate-34(SAPO-34) molecular sieves have important applications in the petrochemical industry as a result of their shape selectivity and suitable acidity. In this work, nanoaggregate SAPO-34 with a lar... Silicoaluminophosphate-34(SAPO-34) molecular sieves have important applications in the petrochemical industry as a result of their shape selectivity and suitable acidity. In this work, nanoaggregate SAPO-34 with a large external surface area was obtained by dissolving pseudoboehmite and tetraethylorthosilicate in an aqueous solution of tetraethylammonium hydroxide and subsequently adding phosphoric acid. After hydrolysis in an alkaline solution, the aluminum and silicon precursors exist as Al(OH)4-and SiO2(OH)-, respectively;this is beneficial for rapid nucleation and the formation of nanoaggregates in the following crystallization process. Additionally, to study the effect of the external surface area and pore size on the catalytic performance of different SAPO-34 structures, the alcoholysis of furfuryl alcohol to ethyl levulinate(EL) was chosen as a model reaction. In a comparison with the traditional cube-like SAPO-34, nanoaggregate SAPO-34 generated a higher yield of 74.1% of EL, whereas that with cube-like SAPO-34 was only 19.9%. Moreover, the stability was remarkably enhanced for nanoaggregate SAPO-34. The greater external surface area and larger number of external surface acid sites are helpful in improving the catalytic performance and avoiding coke deposition. 展开更多
关键词 Nanoaggregate SPAO-34 External surface area Low cost Catalytic alcoholysis Furfuryl alcohol
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Ectopic fascioliasis mimicking a colon tumor 被引量:1
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作者 Ozer Makay Baris Gurcu +3 位作者 Cemil Caliskan Deniz Nart Muge Tuncyurek Mustafa Korkut 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第18期2633-2635,共3页
Fasciola hepatica, a leaf shaped trematode that is common in cattle, sheep and goats, is acquired by eating raw water plants like watercress or drinking water infected with the encysted form of the parasite. The varie... Fasciola hepatica, a leaf shaped trematode that is common in cattle, sheep and goats, is acquired by eating raw water plants like watercress or drinking water infected with the encysted form of the parasite. The varied clinical presentations of fascioliasis still make a high index of suspicion mandatory. Besides having a wide spectrum of hepatobiliary symptoms like obstructive jaundice, cholangitis and liver cirrhosis, the parasitic infection also has extrabiliary manifestations. Until recently, extrahepatic fascioliasis has been reported in the subcutaneous tissue, brain, lungs, epididymis, inguinal lymph nodes, stomach and the cecum. In this report, a strange manifestation of the fasciola infection in a site other than the liver, a colonic fascioliasis, is presented. 展开更多
关键词 Fasciola hepatica Ectopic fascioliasis COLON
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Role of AFP mRNA expression in peripheral blood as a predictor for postsurgical recurrence of hepatocellular carcinoma: A systematic review and meta-analysis 被引量:15
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作者 XiangDing Lian-YueYang +8 位作者 Geng-WenHuang Jian-QingYang He-LiLiu WeiWang Ji-XiangPeng Jie-QuanYang Yi-MingTao Zhi-GangChang Xiu-ShouLing 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第17期2656-2661,共6页
AIM:To identify the role of alpha-fetoprotein (AFP) mRNA expression in peripheral blood one week after surgery as a predictor for recurrence of hepatocellular carcinoma (HCC). METHODS: Published studies fulfilling the... AIM:To identify the role of alpha-fetoprotein (AFP) mRNA expression in peripheral blood one week after surgery as a predictor for recurrence of hepatocellular carcinoma (HCC). METHODS: Published studies fulfilling the selection criteria were identified by searching several databases online. After a methodology assessment using a quality scale designed by European Lung Cancer Working Party, data in each research were aggregated by means of meta-analysis. RESULTS: Altogether 368 cases were included in the 9 selected studies, which fulfilled the selection criteria. The quality scores ranged from 35% to 84% with a median score of 55%. The 'design' subscore had the lowest median value (38%). By aggregating the data, a high x2 value (77.576) was presented. The fail-safe number was 136 and 64 for P= 0.05 and 0.01, respectively. CONCLUSION: AFP mRNA expression in peripheral blood 1 wk after surgery correlated with the recurrence of HCC and was a good predictor for tumor recurrence. 展开更多
关键词 AFP mRNA HCC META-ANALYSIS
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Calcified reticulate rind sign:A characteristic feature of gossypiboma on computed tomography 被引量:8
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作者 Yi-Ying Lu Yun-Chung Cheung +1 位作者 Sheung-Fat Ko Shu-Hang Ng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第31期4927-4929,共3页
We herein report a gossypiboma resulting from a retained surgical swab, which had been left in peritoneum for 20years after appendectomy. CT revealed a cystic mass with a calcified reticulate rind. Subsequent surgery ... We herein report a gossypiboma resulting from a retained surgical swab, which had been left in peritoneum for 20years after appendectomy. CT revealed a cystic mass with a calcified reticulate rind. Subsequent surgery and pathological examination showed a gossypiboma. A simple experiment, using a barium-soaked surgical swab demonstrating similar CT appearance, supported our postulation that calcium deposition on the reticulated fibers of a surgical swab could generate such a characteristic 'calcified reticulate rind' sign. We believe that identification of this CT sign facilitates the diagnosis of gossypibomas. 展开更多
关键词 GOSSYPIBOMA TEXTILOMA Retained surgical swab CT
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Driving characteristics of octagon-type ultrasonic motor 被引量:1
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作者 KIM Jong-Wook PARK Choong-Hyo +3 位作者 LIM Jung-Hoon JEONG Seong-Su PARK Jong-Kyu PARK Tae-Gone 《Journal of Central South University》 SCIE EI CAS 2013年第1期71-75,共5页
Structure of the octagon-type ultrasonic motor was proposed and designed so as to allow the motor to drive small actuator. The stator of the motor consisted of the octagon shape elastic body and four rectangular plate... Structure of the octagon-type ultrasonic motor was proposed and designed so as to allow the motor to drive small actuator. The stator of the motor consisted of the octagon shape elastic body and four rectangular plate ceramics. The four ceramics were attached to outer surfaces of the octagon elastic body. The same phase voltages were applied to the ceramics on horizontal surfaces, and 90° phase difference voltages were applied to the ceramics on vertical surfaces. When the AC voltage with 90° phase difference was applied in ceramics, the elliptical displacement of unimorph bars was generated by generating bending vibration. To find the maximum displacement model that generates elliptical displacement at the centers of the inner surfaces, the finite element analysis program ATILA was used. The analyzed results were compared to the experimental results. As a result, the speed and torque are increased linearly by increasing the input voltage and the speed of motors can be controlled by changing the applied voltages. 展开更多
关键词 octagon-type 90° phase difference ultrasonic motor ATILA
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Fabrication of titanium-based alloys with bioactive surface oxide layer as biomedical implants:Opportunity and challenges 被引量:10
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作者 Mohamad Rodzi SITI NUR HAZWANI Ling Xin LIM +1 位作者 Zainovia LOCKMAN Hussain ZUHAILAWATI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第1期1-44,共44页
Titanium and its alloys have long been used as implant materials due to their outstanding mechanical properties and apparent biocompatibility.Despite this,the search for better alloys has continued to be active by res... Titanium and its alloys have long been used as implant materials due to their outstanding mechanical properties and apparent biocompatibility.Despite this,the search for better alloys has continued to be active by researchers and industries alike,as there are still pressing issues that require attention.These include(1)a large mismatch in the elastic modulus of the implant material,which causes a stress shielding problem;(2)the release of harmful ions from Ti alloys after long-term use;(3)a low bioactivity of the Ti alloy surface,which prolongs the healing process.More research has been directed toward finding new generation Ti alloys composed of more biocompatible phases and modifying the surface of Ti alloys from naturally bio-inert to bioactive in order to circumvent the problems.This review examines recent work reported on the fabrication of Ti alloys,and based on the survey,major characteristics highlighted the importance of elastic modulus and the use of non-toxic metal elements to improve biocompatibility.In terms of surface modification of Ti alloys,numerous studies have found that a nano-scaled surface oxide layer grown on the surface is always beneficial to improving the bioactivity of Ti alloys for rapid recovery after implantation.This comprehensive review focuses on the appropriate phase and composition for new Ti alloys intended for use as biomedical implants,emphasizing both fabrication and surface modification methods. 展开更多
关键词 titanium alloy orthopedic application surface modification TiO_(2)nanotubes
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A New Look at Building Facades as Infrastructure 被引量:2
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作者 Doris Sung 《Engineering》 SCIE EI 2016年第1期63-68,共6页
Like the hard surfaces of streets and sidewalks in an urban environment, the vertical and horizontal surface area on the outside of urban buildings contributes to the constant heating of large cities around the world.... Like the hard surfaces of streets and sidewalks in an urban environment, the vertical and horizontal surface area on the outside of urban buildings contributes to the constant heating of large cities around the world. However, little is done to design this surface to benefit the public sphere. Instead, the facade of a building performs either as a component that focuses only on the quality of comfort for interior occupants, while ignoring effects on the exterior of the building, or as an identifiable aesthetic for the building's owners, This essay proposes the rethinking of the building facade as a steward of outdoor pedestrian welfare, and the conception of public health as an added function of the building envelope- a concept that may fall into the jurisdiction of public works. If the huge total surface area of a city's buildings is thought of as part of the city's infrastructure, then its public contribution may not only make outdoor areas comfortable, clean, and enjoyable, but also help to alleviate the bigger problem of rising temperatures in cities. 展开更多
关键词 Building facade infrastructure Public pedestrian comfort Building facades for public Health
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