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全球机器人未来发展趋势
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作者 亚历山大·维尔 《新经济导刊》 2023年第8期4-6,共3页
国际机器人联合会(IFR)是一个拥有3000多家全球企业的联合会,是高校、科研机构、企业共同打造的“产学研”创新合作平台,致力于分析、汇总行业相关数据,进而推动整个机器人产业发展。机器人最新的技术应用和新的赋能平台有哪些?我们可... 国际机器人联合会(IFR)是一个拥有3000多家全球企业的联合会,是高校、科研机构、企业共同打造的“产学研”创新合作平台,致力于分析、汇总行业相关数据,进而推动整个机器人产业发展。机器人最新的技术应用和新的赋能平台有哪些?我们可以从工业机器人和服务机器人的应用情况来了解机器人行业最新的发展趋势。 展开更多
关键词 工业机器人 服务机器人 机器人产业 科研机构 产学研 合作平台 未来发展趋势
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Estimation of aboveground biomass of arboreal species in the semi-arid region of Brazil using SAR(synthetic aperture radar)images
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作者 Janisson B de JESUS Tatiana M KUPLICH +2 位作者 Íkaro D de C BARRETO Fernando L HILLEBRAND Cristiano N da ROSA 《Journal of Arid Land》 SCIE CSCD 2023年第6期695-709,共15页
The Caatinga biome is an important ecosystem in the semi-arid region of Brazil.It has significantly degraded due to human activities and is currently a region undergoing desertification.Thus,monitoring the variation i... The Caatinga biome is an important ecosystem in the semi-arid region of Brazil.It has significantly degraded due to human activities and is currently a region undergoing desertification.Thus,monitoring the variation in the Caatinga biome has become essential for its sustainable development.However,traditional methods for estimating aboveground biomass(AGB)are time-consuming and destructive.Remote sensing,such as optical and radar imaging,can estimate and correlate with vegetation.Nevertheless,radar imaging is still a novelty to be applied in estimating the AGB of this biome,which is an area with little research.Therefore,this study aimed to use Sentinel-1 images to estimate the AGB of the Caatinga biome in Sergipe State(northeastern Brazil)and to verify its influencing factors.Nineteen sample plots(30 m×30 m)were selected,and the stems of individuals with a circumference at breast height(1.3 m above the ground)equal to or greater than 6.0 cm were measured,and the AGB through an allometric equation was estimated.The Sentinel-1 images from 3 different periods(green,intermediate,and dry periods)were used to consider the phenological conditions of the Caatinga biome.All the pre-processing and extraction of attributes(co-polarized VV(vertical transmit and vertical receive),cross-polarized VH(vertical transmit and horizontal receive),and band ratio VH/VV backscatter,radar vegetation index,dual polarization synthetic aperture radar(SAR)vegetation index(DPSVI),entropy(H),and alpha angle(α))were performed with Sentinel’s Application Platform.These attributes were used to estimate the AGB through simple and multiple linear regressions and evaluated by the coefficients of determination(R2),correlation(r),and root mean squared error(RMSE).The results showed that the attributes individually had little ability to estimate the AGB of the Caatinga biome in the three periods.Combined with multiple regression,we found that the intermediate period presented the equation with the best results among the observed and estimated variables(R^(2)=0.73;r=0.85;RMSE=8.33 Mg/hm^(2)),followed by the greenness period(R2=0.72;r=0.85;RMSE=8.40 Mg/hm^(2)).The attributes contributing to these equations were VH/VV,DPSVI,H,α,and co-polarized VV for the green period and cross-polarized VH for the intermediate period.The study showed that the Sentinel-1 images could be used to estimate the AGB of the Caatinga biome in the green and intermediate phenological periods since the SAR attributes highly correlated with the estimated variable(i.e.,AGB)through multiple linear equations. 展开更多
关键词 CAATINGA tropical dry forest coherent and incoherent attributes C-band Sentinel-1
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从白腐菌中筛选漆酶高产菌株的初步研究(英) 被引量:9
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作者 唐舜 A.LOMASCOLO +7 位作者 郭林 J.C.SIGOILLOT 文华安 卯晓岚 王文惠 J.L.ROBERT C.ANTONA M.ASTHER 《菌物系统》 CSCD 北大核心 2001年第4期520-525,共6页
从中国分离的149株木腐菌中,有30株具有漆酶活性。在添加了阿魏酸的液体培养基中,漆酶产量高(每升培养液中漆酶含量在10000单位以上)的菌株有9个:游离细胞培养的彩绒革盖菌Coriolus versicolor G30,相邻小孔菌Microporus affinis G07,... 从中国分离的149株木腐菌中,有30株具有漆酶活性。在添加了阿魏酸的液体培养基中,漆酶产量高(每升培养液中漆酶含量在10000单位以上)的菌株有9个:游离细胞培养的彩绒革盖菌Coriolus versicolor G30,相邻小孔菌Microporus affinis G07,血红密孔菌Pycnoporus sanguineus W006,W006-2,W3008,G05和香菇Lentinus edodes G18,以及固定细胞培养的鲑贝革盖菌Coriolus consors 98563和干酪菌Tyromyces sp. 98420。彩绒革盖菌、相邻小孔菌和血红密孔菌具有重要的生物工程研究价值。 展开更多
关键词 木腐菌 漆酶活性 游离细胞培养 固定细胞培养 密孔菌 革盖菌 白腐菌 高产菌株
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Identification of biomarkers of human pancreatic adenocarcinomas by expression profiling and validation with gene expression analysis in endoscopic ultrasound-guided fine needle aspiration samples 被引量:5
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作者 Henrik Laurell Michèle Bouisson +7 位作者 Philippe Berthelémy Philippe Rochaix Sébastien Déjean Philippe Besse Christiana Susini Lucien Pradayrol Nicole Vaysse Louis Buscail 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第21期3344-3351,共8页
AIM: To compare gene expression profiles of pancreatic adenocarcinoma tissue specimens, human pancreatic and colon adenocarcinoma and leukemia cell lines and normal pancreas samples in order to distinguish differenti... AIM: To compare gene expression profiles of pancreatic adenocarcinoma tissue specimens, human pancreatic and colon adenocarcinoma and leukemia cell lines and normal pancreas samples in order to distinguish differentially expressed genes and to validate the differential expression of a subset of genes by quantitative real-time RT-PCR (RT-QPCR) in endoscopic ultrasound-guided fine needle aspiration (EUS-guided FNA) specimens.METHODS: Commercially dedicated cancer cDNA macroarrays (Atlas Human Cancer 1.2) containing 1176 genes were used. Different statistical approaches (hierarchical clustering, principal component analysis (PCA) and SAM) were used to analyze the expression data. RT-QPCR and immunohistochemical studies were used for validation of results.RESULTS: RT-QPCR validated the increased expression of LCN2 (lipocalin 2) and for the first time PLAT (tissue-type plasminogen activator or tPA) in malignant pancreas as compared with normal pancreas. Immunohistochemical analysis confirmed the increased expression of LCN2 protein localized in epithelial cells of ducts invaded by carcinoma. The analysis of PLAT and LCN2 transcripts in 12 samples obtained through EUS-guided FNA from patients with pancreatic adenocarcinoma showed significantly increased expression levels in comparison with those found in normal tissues, indicating that a sufficient amount of high quality RNA can be obtained with this technique.CONCLUSION: Expression profiling is a useful method to identify biomarkers and potential target genes. Molecular analysis of EUS-guided FNA samples in pancreatic cancer appears as a valuable strategy for the diagnosis of pancreatic adenocarcinomas. 展开更多
关键词 PANCREAS COLON ADENOCARCINOMA Gene expression profiling Endoscopic ultrasonography ULTRASOUND Fine needle aspiration
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Prokineticin 2/Bv8 is expressed in Kupffer cells in liver and is down regulated in human hepatocellular carcinoma 被引量:4
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作者 Justin Monnier Claire Piquet-Pellorce +5 位作者 Jean-Jacques Feige Orlando Musso Bruno Clément Bruno Turlin Nathalie Théret Michel Samson 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第8期1182-1191,共10页
AIM: TO study the implication of prokineticin 1 (PKI/EGVEGF) and prokineticin 2 (PK2/13v8) in hepatocellular carcinoma angiogenesis.METHODS: The gene induction of PK1/EG-VEGF and PK2/Bv8 was investigated in 10 n... AIM: TO study the implication of prokineticin 1 (PKI/EGVEGF) and prokineticin 2 (PK2/13v8) in hepatocellular carcinoma angiogenesis.METHODS: The gene induction of PK1/EG-VEGF and PK2/Bv8 was investigated in 10 normal, 28 fibrotic and 28 tumoral livers by using real time PCR. Their expression was compared to the expression of VEGF (an angiogenesis marker), vWF (an endothelial cell marker) and to CD68 (a monocyte/macrophage marker). Furthermore, the rnRNA levels of PK1/EG-VEGF, PK2/Bv8, prokineticin receptor 1 and 2 were evaluated by real time PCR in isolated liver cell populations. Finally, PK2/Bv8 protein was detected in normal liver paraffin sections and in isolated liver cells by immunohistochernistry and immunocytochemistry.RESULTS: PK2/Bv8 mRNA but not PK1/EG-VEGF was expressed in all types of normal liver samples examined. In the context of liver tumor development, we reported that PK2/13v8 correlates only with CD68 and showed a significant decrease in expression as the pathology evolves towards cancer. Whereas, VEGF and vWF mRNA were significantly upregulated in both fibrosis and HCC,as expected. In addition, out of all isolated liver cells examined, only Kupffer cells (liver resident macrophages) express significant levels of PK2/Bv8 and its receptors, prokineticin receptor 1 and 2.CONCLUSION: In normal liver PK2/Bv8 and its receptors were specifically expressed by Kupffer cells. PK2/Bv8 expression decreased as the liver evolves towards cancer and did not correlate with HCC angiogenesis. 展开更多
关键词 Prokineticin Hepatocellular carcinoma PK2/Bv8 ANGIOGENESIS Kupffer cells Vascular endothelial growth factor LIVER
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Mechanism for Src activation by the CCK2 receptor:Patho-physiological functions of this receptor in pancreas 被引量:2
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作者 Audrey Ferrand Sebastien Vatinel +5 位作者 Aline Kowalski-Chauvel Claudine Bertrand Chantal Escrieut Daniel Fourmy Marlene Dufresne Catherine Seva 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第28期4498-4503,共6页
AIM: TO investigate in vivo, whether CCK2 receptors (CCK2R) regulate proteins known to play a crucial role in cell proliferation and cancer development and analyse in vitro the molecular mechanisms that lead to Src... AIM: TO investigate in vivo, whether CCK2 receptors (CCK2R) regulate proteins known to play a crucial role in cell proliferation and cancer development and analyse in vitro the molecular mechanisms that lead to Src activation; in particular, to identify the domains within the CCK2R sequence that are implicated in this activation. METHODS: The expression and activation of Src and ERK were studied in vivo using immunofluorescence and western-blot techniques. We used pancreatic tissues derived from wild type or Elas-CCK2 mice that expressed the CCK2R in pancreatic acini, displayed an increased pancreatic growth and developed preneoplastic lesions. The pancreatic tumor cell line AR4-2J expressing the endogenous CCK2R or COS-7 cells transiently transfected with wild type or mutant CCK2R were used as in vitro models to study the mechanism of Src activation. Src activation was measured by in vitro kinase assays, ERK activation by western blot using antiphospho-ERK antibodies and the involvement of Src in gastrin-induced cell proliferation by MTT test. RESULTS: We showed in vivo that the targeted CCK2R expression in the pancreas of Elas-CCK2 mice, led to the activation of Src and the ERK pathway. Src was activated upstream of the ERK pathway by the CCK2R in pancreatic tumoral cells and contributed to the proliferative effects mediated by this receptor. In vitro results demonstrated that activation of the Src/ERK pathway by the CCK2R required the NPXXY motif, located within the CCK2R sequence at the end of the 7^th transmembrane domain, and suggested the putative role of Gq in this mechanism. CONCLUSION: Deregulation of the Src/ERK pathway by the CCK2R might represent an early step that contributes to cell proliferation, formation of preneoplastic lesions and pancreatic tumor development. 展开更多
关键词 Gastrin Src PANCREAS CCK2 receptor
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Early plasmapheresis and rituximab for acute humoral rejection after ABO-compatible liver transplantation 被引量:8
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作者 Nassim Kamar Laurence Lavayssière +10 位作者 Fabrice Muscari Janick Selves Céline Guilbeau-Frugier Isabelle Cardeau Laure Esposito Olivier Cointault Marie Béatrice Nogier Jean Marie Peron Philippe Otal Marylise Fort Lionel Rostaing 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第27期3426-3430,共5页
Acute humoral rejection (AHR) is uncommon after ABO- compatible liver transplantation. Herein, we report two cases of AHR treated with plasmapheresis and rituximab in two ABO-compatible liver-transplant patients wit... Acute humoral rejection (AHR) is uncommon after ABO- compatible liver transplantation. Herein, we report two cases of AHR treated with plasmapheresis and rituximab in two ABO-compatible liver-transplant patients with preformed anti-human leukocyte antigen donor-specific antibodies. Patient 1 experienced a biopsy-proven AHR at day 10 post-transplant. She was treated by steroid pulses, and OKT3. Because of persisting signs of biopsy-proven AHR at day 26, she was treated by plasmapheresis and rituximab. Uver enzyme levels did not improve, and she died on day 41. Patient 2 experienced a biopsy-proven AHR on day 10 post-transplant. She was treated by steroid pulses, plasmapheresis, and rituximab. Liver enzymes returned to within normal range 18 d after diagnosis. Uver biopsies, at 3 and 9 mo post-transplant, showed complete resolution of AHR. We conclude that plasmapheresis should be started as soon as AHR is diagnosed, and be associated with a B-cell depleting agent. Rituximab may be considered as a first-line therapy. 展开更多
关键词 Acute humoral rejection Liver transplantation Donor-specific antibodies RITUXIMAB PLASMAPHERESIS
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Quasispecies evolution in NS5A region of hepatitis C virus genotype 1b during interferon or combined interferon-ribavirin therapy 被引量:9
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作者 Pascal Veillon Christopher Payan +2 位作者 Hélène Le Guillou-Guillemette Catherine Gaudy Franoise Lunel 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第8期1195-1203,共9页
AIM: To evaluate the implication of substitutions in the hepatitis C virus (HCV) non-structural 5A (NS5A) protein in the resistance of HCV during mono-interferon (IFN) or combined IFN-ribavirin (IFN-R) therapy. Althou... AIM: To evaluate the implication of substitutions in the hepatitis C virus (HCV) non-structural 5A (NS5A) protein in the resistance of HCV during mono-interferon (IFN) or combined IFN-ribavirin (IFN-R) therapy. Although NS5A has been reported to interact with the HCV RNA- dependent RNA polymerase, NS5B, as well as with many cellular proteins, the function of NS5A in the life cycle of HCV remains unclear. METHODS: HCV quasispecies were studied by clon- ing and sequencing of sequential isolates from patients infected by HCV genotype 1b. Patients were treated by IFN-α2b for 3 mo followed by IFN-α2b alone or com- bined IFN-R therapy for 9 additional months. Patients were categorized intro two groups based on their re- sponse to the treatments: 7 with sustained virological re- sponse (SVR) (quasispecies = 150) and 3 non-respond- ers (NR) to IFN-R (quasispecies = 106). RESULTS: Prior to treatment, SVR patients displayed a lower complexity of quasispecies than NR patients. Most patients had a decrease in the complexity of quasispe- cies during therapy. Analysis of amino acids substitu- tions showed that the degree of the complexity of the interferon sensitivity-determining region (ISDR) and the V3 domain of NS5A protein was able to discriminate thetwo groups of patients. Moreover, SVR patients displayed more variability in the NS5A region than NR patients. CONCLUSION: These results suggest that detailed mo- lecular analysis of the NS5A region may be important for understanding its function in IFN response during HCV 1b infection. 展开更多
关键词 Hepatitis C virus QUASISPECIES NS5A region Interferon sensitivity-determining region V3 domain
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Introduction to Tissular and Cellular Engineering 被引量:1
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作者 JF STOLTZ 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期4-,共1页
关键词 implanted spontaneously UMBILICAL BIOREACTOR EMBRYO potentially MATURE alternatives ETHICAL CULTIVATED
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Glycine-extended gastrin activates two independent tyrosine-kinases in upstream of p85/p110 phosphatidylinositol 3-kinase in human colonic tumour cells 被引量:2
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作者 Audrey Ferrand Aline Kowalski-Chauvel +4 位作者 Claudine Bertrand Daniel Fourmy Marlene Dufresne Catherine Seva Julie Pannequin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第12期1859-1864,共6页
AIM: To investigate whether Src, JAK2 and phosphatidylinositol 3-kinase (PI3K) pathways are involved in the proliferation of human colonic tumour cells induced by glycine-extended gastrin (G-gly), the precursor o... AIM: To investigate whether Src, JAK2 and phosphatidylinositol 3-kinase (PI3K) pathways are involved in the proliferation of human colonic tumour cells induced by glycine-extended gastrin (G-gly), the precursor of the mature amidated gastrin and to elucidate the molecular interaction between these three kinases in response to this peptide. METHODS: Using the human colonic tumour cell line HCT116 as a model, we first measured the activation of PI3K, p60-Src and JAK2 in response to G-gly by in vitro kinase assays. Then we investigated the involvement of these kinases in G-gly-induced cell proliferation by MTT test. RESULTS: G-gly stimulation induced p60-Src, JAK2 and PI3K activation in HCT116. The different pathways were involved in proliferation of human colon cancer cells induced by G-gly. Furthermore, we found that both Src and JAK2 were necessary to PI3K regulation by this peptide. However, we did not find any cross-talk between the two tyrosine kinases. CONCLUSION: Our results suggest that the p60-Src/ PI3K and JAK2/PI3K pathways act independently to mediate G-gly proliferative effect on human colonic tumour cells. 展开更多
关键词 Colon cancer Src JAK2 Phosphatidylinositol 3-kinase Glycine-extended gastrin
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Rck of Salmonella enterica, subspecies enterica serovar Enteritidis, mediates Zipper-like internalization 被引量:4
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作者 Manon Rosselin Isabelle Virlogeux-Payant +7 位作者 Christian Roy Elisabeth Bottreau Pierre-Yves Sizaret Lily Mijouin Pierre Germon Emmanuelle Caron Philippe Velge Agnes Wiedemann 《Cell Research》 SCIE CAS CSCD 2010年第6期647-664,共18页
Salmonella can invade non-phagocytic cells through its type Ⅲ secretion system (T3SS-1), which induces a Trigger entry process. This study showed that Salmonella enterica, subspecies enterica serovar Enteritidis ca... Salmonella can invade non-phagocytic cells through its type Ⅲ secretion system (T3SS-1), which induces a Trigger entry process. This study showed that Salmonella enterica, subspecies enterica serovar Enteritidis can also invade cells via the Rck outer membrane protein. Rck was necessary and sufficient to enable non-invasive E. coli and Rckcoated beads to adhere to and invade different cells. Internalization analysis of latex beads coated with different Rck peptides showed that the peptide containing amino acids 140-150 promoted adhesion, whereas amino acids between 150 and 159 modulated invasion. Expression of dominant-negative derivatives and use of specific inhibitors demonstrated the crucial role of small GTPases Racl and Cdc42 in activating the Arp2/3 complex to trigger formation of actin-rich accumulation, leading to Rck-dependent internalization. Finally, scanning and transmission electron microscopy with Rck-coated beads and E. coli expressing Rck revealed microvillus-like extensions that formed a Zipper-like structure, engulfing the adherent beads and bacteria. Overall, our results provide new insights into the Salmonella T3SS-independent invasion mechanisms and strongly suggest that Rck induces a Zipper-like entry mechanism. Consequently, Salmonella seems to be the first bacterium found to be able to induce both Zipper and Trigger mechanisms to invade host cells. 展开更多
关键词 Salmonella invasion adherence small G-protein actin outer membrane protein Zipper-like entry pathway
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Collaborative Intelligence in Smart Cities: A Systematic Review 被引量:1
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作者 Viviani Kwecko Silvia S. da C. Botelho 《Social Networking》 2018年第3期181-195,共15页
The objective of this research is to present a systematic analysis, in which we seek to identify the concepts of intelligent city, with the intention of recognizing the nature of this intelligence before the participa... The objective of this research is to present a systematic analysis, in which we seek to identify the concepts of intelligent city, with the intention of recognizing the nature of this intelligence before the participation of the population. Therefore, the research associates concepts as smart cities, citizen participation and social web, identifying publications between 2012 and the first quarter of 2018 and questioning what the intelligent city is and how this concept is able to (re)organize the learning processes of the territory from the informal dynamics of the contemporary city. The qualitative analysis of the documents revealed an innumerable of definitions and related terms: smart, intelligent, ubiquitous, digital, knowledge, sustainable, crowd sourcing, innovative;structured in three types of approaches: technological focus, focus on human resources and focus on citizen-related governance from the following domains: media convergence, public and regulatory information policies, infrastructure management, real-time data mining and extraction, geographic information system, crowd computing, smart cities education, and social monitoring and control. In spite of the access to a great amount of data, we verify that the concept of intelligent city is referenced by a significant number of researches, but, in smaller number, works that present models of construction of a collective intelligence for the city. From this perspective, we identified the need to recognize technological education interventions for communication between individuals and the city. Because we believe that only through the implementation and management of techno-educommunication ecosystems will be able to promote a culture of participation. 展开更多
关键词 TERRITORIAL Learning Non-Formal Education TECHNOLOGICAL ARTIFACTS INFORMAL Dynamics CITIZEN PARTICIPATION
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High tacrolimus intra-patient variability is associated with graft rejection,and de novo donor-specific antibodies occurrence after liver transplantation 被引量:7
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作者 Arnaud Del Bello Nicolas Congy-Jolivet +6 位作者 Marie Danjoux Fabrice Muscari Laurence Lavayssière Laure Esposito Anne-Laure Hebral Julie Bellière Nassim Kamar 《World Journal of Gastroenterology》 SCIE CAS 2018年第16期1795-1802,共8页
AIM To investigate the role of tacrolimus intra-patient variability(IPV) in adult liver-transplant recipients.METHODS We retrospectively assessed tacrolimus variability in a cohort of liver-transplant recipients and a... AIM To investigate the role of tacrolimus intra-patient variability(IPV) in adult liver-transplant recipients.METHODS We retrospectively assessed tacrolimus variability in a cohort of liver-transplant recipients and analyzed its effect on the occurrence of graft rejection and de novo donor-specific antibodies(dn DSAs), as well as graft survival during the first 2 years posttransplantation. Between 02/08 and 06/2015, 116 patients that received tacrolimus plus mycophenolate mofetil(with or without steroids) were included. RESULTS Twenty-two patients(18.5%) experienced at least one acute-rejection episode(BPAR). Predictive factors for a BPAR were a tacrolimus IPV of > 35% [OR = 3.07 95%CI(1.14-8.24), P = 0.03] or > 40% [OR = 4.16(1.38-12.50), P = 0.01), and a tacrolimus trough level of < 5 ng/mL [OR=3.68(1.3-10.4), P =0.014]. Thirteen patients(11.2%) developed at least one dn DSA during the follow-up. Tacrolimus IPV [coded as a continuous variable: OR = 1.1, 95%CI(1.0-1.12), P = 0.006] of > 35% [OR = 4.83, 95%CI(1.39-16.72), P = 0.01] and > 40% [OR = 9.73, 95%CI(2.65-35.76), P = 0.001] were identified as predictors to detect dn DSAs. IPV did not impact on patient-or graft-survival rates during the follow-up. CONCLUSION Tacrolimus-IPV could be a useful tool to identify patients with a greater risk of graft rejection and of developing a de novo DSA after liver 展开更多
关键词 VARIABILITY Liver transplantation Donorspecific ANTIBODIES IMMUNOSUPPRESSION
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Dorsal root ganglion progenitors differentiate to gamma-aminobutyric acid-and choline acetyltransferase-positive neurons 被引量:1
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作者 Lingli Yu Yindi Ding +4 位作者 Ambre Spencer Ji Ma Ruisheng Lu Brian B.Rudkin Chonggang Yuan 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第7期485-491,共7页
This study examined the isolation and differentiation of dorsal root ganglion progenitor cells for therapeutic use in neurodegenerative diseases. Rat embryonic dorsal root ganglia progenitors were isolated and purifie... This study examined the isolation and differentiation of dorsal root ganglion progenitor cells for therapeutic use in neurodegenerative diseases. Rat embryonic dorsal root ganglia progenitors were isolated and purified using the differential adhesion method combined with cytosine arabinoside treatment. After culture in serum-free medium supplemented with B27, basic fibroblast growth factor and epidermal growth factor, these cells remained viable and survived for more than 18 months in vitro. Most cells differentiated to neurons that were immunoreactive for gamma-aminobutyric acid and choline acetyltransferase as detected by immunohistochemical staining. In addition, nerve growth factor and neurotrophic tyrosine kinase receptor expression were also observed in dorsal root ganglion progenitors and differentiated cells. K252a, an inhibitor that blocks nerve growth factor-induced signaling, inhibited cell survival, suggesting the possible existence of a nerve growth factor autocrine loop in these proliferating cells. 展开更多
关键词 dorsal root ganglion neural progenitor differentiation characterization nerve growth factor tyrosine kinase receptor type 1
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A Multiscale Assessment of the Risks Imposed by Plantation Forestry on Plant Biodiversity in the Hotspot Central Chile 被引量:1
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作者 Andreas Ch. Braun Joachim Vogt 《Open Journal of Ecology》 2014年第16期1025-1044,共20页
We assessed the effects of plantations of exotic trees (Pinus radiata, Eucalyptus globulus, and Populus nigra) on plant biodiversity in the temperate zone of the biodiversity hotspot of Central Chile. This region has ... We assessed the effects of plantations of exotic trees (Pinus radiata, Eucalyptus globulus, and Populus nigra) on plant biodiversity in the temperate zone of the biodiversity hotspot of Central Chile. This region has suffered from intense deforestation in favor of plantation establishment in the major part of the coastal area since the neoliberal turn in 1973. The approach presented aimed to analyze plant biodiversity on the α-, β- and γ-scale. Furthermore, a plantation evaluation index was applied in order to provide quantitative figures on management practices. Species richness is reduced by 50% below plantations. Diversity and evenness index values are also significantly reduced. Analyses on β-similarity indicate that plantations do not host species absent in adjacent native forests, and no additional habitat heterogeneity is gained. On the γ-scale, plantations lower the number of total species observed;especially of endemic species. The abundance of species considered as invasive is significantly higher and frequently, invasive plants dominate the understory. The evaluation index attests rather poor plantation management in Central Chile since plantations are grown as monocultures, natural elements and native species are lacking at specific sites and plantations are insufficiently connected to native plant formations at the landscape scale. Results give much concern since deforestation processes as observed in our study area is about to begin in Patagonia as well. If management practices from the temperate zone are adopted in Patagonia, a considerable decline in plant biodiversity has to be expected there. 展开更多
关键词 BIODIVERSITY DECLINE Plantations BIODIVERSITY HOTSPOT PINUS radiate EUCALYPTUS globules Chile
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High-magnification observation of seminiferous tubules through the tunica albuginea by two-photon laser scanning microscopy 被引量:4
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作者 Vincent Achard Pascal Weber +1 位作者 Georges Mercier Marie-Pierre Blanchard 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第5期774-776,共3页
Testicular sperm extraction is widely used in the treatment of male infertility in cases of non-obstructive azoospermia. Identifying spermatogenetic foci within the testes is critical for testicular sperm extraction. ... Testicular sperm extraction is widely used in the treatment of male infertility in cases of non-obstructive azoospermia. Identifying spermatogenetic foci within the testes is critical for testicular sperm extraction. Two-photon laser scanning microscopy (TPLSM) is an autofluorescence-based microscopy technique that allows observation at a cellular level in the depth of fresh living tissues and does not require any histological processing (fixation or staining). The wavelengths previously used have shown no phototoxicity on sperm. We used TPLSM to detect spermatogenetic foci in fresh mouse testicular parenchyma without disrupting the tunica albuginea. Fresh surgically retrieved testes were observed using TPLSM within 1 h after extraction. Contralateral testes for each animal were observed using standard histology. Using TPLSM we were able to observe and measure the diameter of seminiferous tubules through the tunica albuginea, similar to the histological control. Structures within epithelial tubules were also observed, although their nature has yet to be identified. TPLSM is a real-time microscopy technique that could detect spermatogenetic foci. 展开更多
关键词 seminiferous epithelium SPERMATOGENESIS
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Isolation and Characterization of Enterococci Bacteriocinic Strains from Tunisian Fish Viscera 被引量:1
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作者 Migaw Sarra Ghrairi Taoufik +3 位作者 Le Chevalier Patrick Brillet Benjamin Fleury Yannick Hani Khaled 《Food and Nutrition Sciences》 2013年第6期701-708,共8页
A collection of lactic acid bacteria isolates from fish viscera was studied and investigated regarding to their functional properties and safety aspects. From these, three isolates GM1, GM2 and GM3 were identified as ... A collection of lactic acid bacteria isolates from fish viscera was studied and investigated regarding to their functional properties and safety aspects. From these, three isolates GM1, GM2 and GM3 were identified as Enterococcus feacium species using molecular methods. Partial Amplified rDNA Restriction Analysis (partial ARDRA) with restriction enzyme HaeIII separated these isolates into distinctive group which suggest genotypic variability within enterococci strains isolated from fish viscera. The three strains GM1, GM2 and GM3 exhibited antimicrobial activity. Indeed strains have been shown to produce bacteriocins with inhibitory effect against food spoilage bacteria and pathogenic fish including Carnobacterium maltaromaticum. The molecular mass of bacteriocin, as calculated by tricine-SDS-PAGE, was found to be 4.5 kDa. All isolates were tested positive upon PCR amplification of enterocin A structural gene. Investigations of antibiotic resistance show that the isolates were mostly sensitive to several antibiotics (ampicillin, penicillin, tetracycline, gentamycine) and resistance to rifampicin. All isolates grow in esculin azide agar as a selective medium for enumeration of probiotic enterococci. This study suggests that our strains can be employed as probiotic or to improve the safety of food products. 展开更多
关键词 BACTERIOCINS FISH VISCERA Enterococcus LISTERIA CARNOBACTERIUM Probiotic
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中国工业机器人数量将在2017年超过欧盟和北美
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《工具技术》 北大核心 2015年第4期I0012-I0012,共1页
据国际机器人联盟(IFR)2014年世界机器人的统计数据显示,到2017年,中国工厂的工业机器人数量将超过欧盟或北美,预计从目前的20万套增加到超过40万套。在北美,工业机器人数量将上升至30万套,而欧洲五大经济体的预测数据为34万套。
关键词 工业机器人 北美 欧盟 中国 数据显示 预测数据
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Chronic hepatitis B liver disease in patients living in the Amazon region: S gene mutations and genotypes characterization 被引量:1
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作者 Deusilene Vieira Marie Gauthier +6 位作者 Larissa Deadame de Figueiredo Nicolete Alcione Oliveira dos Santos Carina Picelli Eduardo Honda Glaucia Paranhos-Baccala Guy Vernet Juan Miguel Villalobos Salcedo 《World Journal of Cardiovascular Diseases》 2013年第8期506-511,共6页
The Amazon region is considered to be a high endemic area for Hepatitis B Virus (HBV) infections, Rond&ocirc;nia state having the highest prevalence. The aim of this study was to identify molecular genotypes and m... The Amazon region is considered to be a high endemic area for Hepatitis B Virus (HBV) infections, Rond&ocirc;nia state having the highest prevalence. The aim of this study was to identify molecular genotypes and mutations in the S gene region of HBV viral genomes from 20 patients using a DNA microarray. Results: Serological tests showed that 88% of patients were HBeAg negative, 82% had anti-HBe antibodies and 33% were co-infected with Hepatitis Delta Virus. Sixteen percent of the patients were considered cirrhotic, and 11% have been transfused. The microarray technique identified the genotypes A (4 patients), D (7 patients) and F (7 patients) in 18 samples. Mutations were detected in all 3 genotypes and, overall, A159G, which has been associated with a reduced antigenicity of the virus, was detected most frequently. In genotype A, G119E was the most frequently detected mutation followed by mutations A159G, F134Y, W172C, Y161F and T143S. A159G was detected in all genotype D and F samples followed by mutations T143S, Y161F, N131T, T114S and G119E in genotype D and mutations T143S, Y161F, N131T, T114S and G119E in genotype F. Conclusion: The analysis of mutations repartition among genotypes suggests that some of them are preferentially or exclusively associated with genotype A, D or F. This type of tool is adapted for clinical and therapy monitoring of patient as well as for molecular epidemiology research on HBV. 展开更多
关键词 Hepatitis B Virus Mutant Detection DNA Microarray Amazon Region
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Taxonomic Diversity and Taxonomic Dominance: The Example of Forest Plantations in South-Central Chile
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作者 Andreas Ch. Braun 《Open Journal of Ecology》 2015年第5期199-212,共14页
The study describes an analysis of the impact of plantation forestry on the taxonomic diversity of plants in south-central Chile. In this biodiversity hotspot, plantations of non-native species like Pinus radiata D. D... The study describes an analysis of the impact of plantation forestry on the taxonomic diversity of plants in south-central Chile. In this biodiversity hotspot, plantations of non-native species like Pinus radiata D. Don, Eucalyptus globules Labill. and Populus nigra L. have largely replaced native deciduous and sclerophyllous forests. The study compares taxonomic diversity of commercial plantations and native forests using taxonomic distinctness and diversity and the Simpson diversity index. Most of these indexes attest a considerably reduced taxonomic diversity to plantations. However, taxonomic distinctness values for P. radiata plantations seem to contradict other indexes at first glance. It is shown that the higher values of taxonomic distinctness of P. radiata plantations come from taxonomic dominance. Taxonomic dominance describes the fact that P. radiate—a member of the infradivison of Gymnospermae-bears only little taxonomic resemblance to other plants, which are Angiospermae. Thus, it strongly dominates the taxonomic distinctness index and the high taxonomic resemblance of other plant within its plots is neglected. Indexes are developed that identify such dominant species and adjust for taxonomic dominance in taxonomic diversity analyses. After this adjustment, all indexes provide a coherent image on taxonomic diversity. Plantation forestry produces a considerable decline of taxonomic diversity. Taxonomic diversity analysis provides valuable insights in biodiversity impacts and complements standard analyses. 展开更多
关键词 TAXONOMIC Diversity Central Chile Biodiversity HOTSPOTS PLANTATION Forestry PINUS RADIATA
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