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| 1 | Mechanism of chain propagation for the synthesis of polyoxymethylene dimethyl ethers显示文摘Polyoxymethylene dimethyl ethers(PODE)were synthesized from the reaction of paraformaldehyde with dimethoxymethane(DMM)over different acid catalysts at different conditions.Products were found to follow the Schulz-Flory distribution law.The chain propagation proceeds through the insertion of an individual segment of CH2O one by one,while the simultaneous insertion of a few CH2O segments or their assembly is unlikely.Due to the restriction of this law,it is difficult to increase the selectivity to the desired products(e.g.,PODE3 4). | Yupei Zhao Zheng Xu Hui Chen Yuchuan Fu Jianyi Shen | 2013 | Journal of Energy Chemistry2013，22，6： | 36 |
| 2 | The relation between HLA-DQA1 genes and genetic susceptibility to duodenal ulcer in Wuhan Hans显示文摘AIM To study the genetic susceptibility of HLA-DQA1 alleles to duodenal ulcer in Wuhan Hans.METHODS Seventy patients with duodenalulcer and fifty healthy controls were examinedfor HLA-DQA1 genotypes.HLA-DQA1 typing wascarried out by digesting the locus specificpolymerase chain reaction amplified productswith alleles specific restriction enzymes(PCR-RFLP),i.e.,Apal Ⅰ,Bsaj Ⅰ,Hph Ⅰ,Fok Ⅰ,Mbo Ⅱ and Mnl Ⅰ.RESULTS The allele frequencies of DQA1 * 0301and DQA1 * 0102 in patients with duodenal ulcerwere significantly higher and lower respectivelythan those in healthy controls(0.40 vs 0.20,P = 0.003,mcorret = 0.024)and(0.05 vs 0.14,P = 0.012,but Pcorret>0.05),respectively.CONCLUSION DQA1 * 0301 is a susceptiblegene for duodenal ulcer in Wuhan Hans,andthere are immunogenetic differences in HLA-DQA1 locus between duodenal ulcer patients andhealthy controls. | Du YP Deng CS Lu DY Huang MF Guo SF Hou W | 2000 | World Journal of Gastroenterology2000，6，1： | 37 |
| 3 | Matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1 expression in fibrotic rat liver显示文摘INTRODUCTIONLiver fibrosis is an excessive deposition ofextracellular matrix(ECM)resulted from bothincreased synthesis and decreased degradation.Matrix metalloproteinases(MMPs)represent agroup of neutral proteinases with variable | Liu HL Li XH Wang DY Yang SP | 2000 | World Journal of Gastroenterology2000，6，6： | 31 |
| 4 | Analysis of point mutation in site 1896 of HBV precore and its detection in the tissues and serum of HCC patients显示文摘INTRODUCTION Hepatitis B is one of the common infectious diseases,which severely impairs the health of the people in our country and has close relationship | Yuan Wang Hu Liu Qing Zhou Xu Li | 2000 | World Journal of Gastroenterology2000，6，3： | 33 |
| 5 | 用学术影响力评价学术论文——兼论关于学术传承效应和长期引用的两个新指标显示文摘1引言
学术论文是科学技术研究,特别是自然科学基础研究成果的重要表现形式,对其学术影响力的研究一直被科技界所关注.研究学术影响力的一个重要方面是后续学术论文与之前发表的学术论文具有什么关系,这种研究对于学术创新具有重大意义. | 尚海茹 冯长根 孙良 | 2016 | 科学通报2016，61，26： | 31 |
| 6 | HCV-RNA positivity in peripheral blood mononuclear cells of patients with chronic HCV-infection: does it really mean viral replication?显示文摘AIM To analyze the association of HCV-RNA with peripheral blood mononuclear cells (PBMC)and to answer the question whether HCV-RNA positivity in PBMC is due to viral replication,METHODS HCV-RNA was monitored in serumand PBMC preparations from 15 patients with chronic HCV infection before, during and after an IFN-α therapy using a nested RT/ PCRtechnique. In a second approach, PBMC from healthy donors were incubated in HCV positive plasma.RESULTS In the IFN-α responding patients,HCV-RNA disappeared first from total RNApreparations of PBMC and then from serum. In contrast, in relapsing patients, HCV-RNAreappeared first in serum and then in PBMC. A quantitative analysis of the HCV-RNAconcentration in serum was performed before and after transition from detectable to nondetectable HCV-RNA in PBMC-RNA and vice versa. When HCV-RNA was detectable in PBMCpreparations, the HCV concentration in serum was significantly higher than the serum HCV-RNA concentration when HCV-RNA in PBMC was not detectable. Furthermore, at no time during the observation period was HCV specific RNA observed in PBMC, if HCV-RNA in serum was under the detection limit. Incubation of PBMCfrom healthy donors with several dilutions of HCV positive plasma for two hours showed a concentration-dependent PCR-positivity for HCV-RNA in reisolated PBMC.CONCLUSION The detectability of HCV-RNA in total RNA from PBMC seems to depend on the HCV concentration in serum. Contamination or passive adsorption by circulating virus could be the reason for detection of HCV-RNA in PBMCpreparations of chronically infected patients. | Volker Meier Sabine Mihm Perdita Wietzke-Braun Guliano Ramadori | 2001 | World Journal of Gastroenterology2001，7，2： | 29 |
| 7 | Helicobacter pylori vacA genotypes and cagA status and their relationship to associated diseases显示文摘INTRODUCTIONHelicobacter pylori(H.pylori)is a major causativebacterium of chronic gastritis,peptic ulcer and mucosa-associated lymphoid tissue lymphoma in humans,andassociated with an increased risk of gastric cancer. | Hou P Tu ZX Xu GM Gong YF Ji XH Li ZS | 2000 | World Journal of Gastroenterology2000，6，4： | 27 |
| 8 | Pathways of Influence of the Northern Hemisphere Mid–high Latitudes on East Asian Climate: A Review显示文摘This paper reviews recent progress made by Chinese scientists on the pathways of influence of the Northern Hemisphere mid-high latitudes on East Asian climate within the framework of a“coupled oceanic-atmospheric(land-atmospheric or seaice-atmospheric)bridge”and“chain coupled bridge”.Four major categories of pathways are concentrated upon,as follows:Pathway A—from North Atlantic to East Asia;Pathway B—from the North Pacific to East Asia;Pathway C—from the Arctic to East Asia;and Pathway D—the synergistic effects of the mid-high latitudes and tropics.In addition,definitions of the terms“combined effect”,“synergistic effect”and“antagonistic effect”of two or more factors of influence or processes and their criteria are introduced,so as to objectively investigate those effects in future research. | Jianping LI Fei ZHENG Cheng SUN Juan FENG Jing WANG | 2019 | Advances in Atmospheric Sciences2019，36，9： | 27 |
| 9 | Effect of myosin heavy chain composition of muscles on meat quality in Laiwu pigs and Duroc显示文摘In order to explain the mechanism of high meat quality in Laiwu pigs and investigate the relation between myosin heavy chains (MyHC) composition and meat quality, meat quality analysis was conducted and mRNA expression of MyHC I, IIa, IIx, IIb was quantified by real-time fluorescence PCR in longissimus muscle (LM) and semimembranous muscle of Laiwu pigs and Duroc. The result indicated that, compared with Duroc, mRNA expression of MyHC IIa, IIx in LM and semimembranous muscle of Laiwu pigs was significantly increased, mRNA expression of MyHC IIb was dramatically decreased. However, the expression of MyHC I was not significantly affected by breeds. The correlation between mRNA expression of MyHC I, IIa, IIx in LM and meat color, pH value, marbling, intramuscular fat content was positive, but shear value of LM was negative. The relation between MyHC IIb mRNA expression and marbling, intramuscular fat content was dramatically negative, whereas shear value was strikingly positive, as well as fiber diameter, but without reaching statistical significance. Therefore, the composition of MyHC I, IIa, IIx, IIb affected meat quality, furthermore, expression of MyHC I, IIa, IIx, IIb mRNA prominently influenced meat characteristics, especially edible quality of muscle, suggesting that mRNA expression level of MyHC I, IIa, IIx, IIb can exactly and impersonally estimate meat quality. | HU HongMei, WANG JiYing, ZHU RongSheng, GUO JianFeng & WU Ying Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan 250100, China | 2008 | Science China(Life Sciences)2008，51，2： | 26 |
| 10 | 基于多目标遗传算法和FLUS模型的西北农牧交错带土地利用优化配置显示文摘西北农牧交错带生态环境脆弱,区位特殊性和生态重要性使其在我国社会经济发展和生态环境保护方面具有重要战略意义。通过对该区域进行土地利用优化配置,使有限的土地资源支撑起生态环境保护和经济发展的重任是本文的出发点。多目标遗传算法和FLUS模型的应用可以从多方面(数量结构、空间布局、综合效益)完善土地利用优化配置,为土地利用优化配置提供更多的选择方案。本文选用多目标遗传算法和FLUS模型对该区域进行2025年的土地利用变化模拟,通过设置自然发展、生态保护优先、经济发展优先、生态-经济均衡4种情景,探讨了如何在兼顾生态环境保护与社会经济发展的情况下进行土地利用的优化配置。结果表明,基于生态-经济均衡情景下的优化方案,土地利用类型的数量结构和空间布局更为合理,其综合效益优于另外3种情景。该情景在合理限制经济发展速度的前提下,使生态建设获得稳定发展,其经济效益较生态保护优先情景下增长了8.96%,生态效益较经济发展优先情景下增长了0.77%,在生态保护与经济发展2种目标之间达到平衡,为西北农牧交错带的土地利用规划提供了决策辅助。 | 杨露 颉耀文 宗乐丽 邱天 焦继宗 | 2020 | 地球信息科学学报2020，22，3： | 26 |
| 11 | 鼻腔及鼻窦内翻性乳头状瘤与人乳头状瘤病毒感染及病毒亚型的关系显示文摘目的 采用多聚酶链反应 (polymerasechainreaction, PCR)检测鼻腔及鼻窦内翻性乳头状瘤(nasalinvertedpapilloma,NIP)中人乳头状瘤病毒 (humanpapillomavirus, HPV)DNA及其亚型,旨在探讨HPV在NIP发病中的作用及其与预后的关系。方法 将 28例鼻腔及鼻窦NIP分为无复发组、复发组、癌变组,用聚合酶链反应检测其HPV通用型、6、11、16及 18型的感染情况,同时以10例慢性炎症鼻黏膜或炎症性鼻息肉病例为对照。结果 28例NIP患者HPV DNA总阳性率为75% (21例)。无复发组病例HPV DNA阳性率为 42% (5 /12),均为单一的低危型HPV感染 (4例为HPV6型, 1例为HPV11型);复发组的 13例和癌变组的 3例中,均可检出HPV DNA。复发者以检出HPV6、HPV11型DNA为主, 4例具有双重感染。癌变者以检出HPV16、HPV18型DNA为主,其中2例为双重感染。结论NIP的发生与HPV感染密切相关。应用PCR检测HPV及各亚型感染情况有助于预测肿瘤的临床行为及预后, 指导临床对高危患者进行重点监测。 | 卢山珊 周韧 徐纪为 | 2005 | 中华耳鼻咽喉头颈外科杂志2005，40，3： | 22 |
| 12 | Expression of the CagA gene of H.pylori and application of its product显示文摘INTRODUCTION Helicobaeter PYlori(HP)Plays an important role inthe uPPer digestive traet diseases.It can be dividedinto two main groups(toxie and non一toxieHP)aeeording to the | Han FC Yan XJ Su CZ | 2000 | World Journal of Gastroenterology2000，6，1： | 22 |
| 13 | Relationship between expression of α-fetoprotein messenger RNA and some clinical parameters of human hepatocelular carcinoma显示文摘METHODWedetectedtheexpressionofAFPinmRNAlevelintissuesamplesfrom52patientssuferingfromHCCbyRTPCRmethod.RESULTSThepositiverat... | HE Ping, TANG Zhao You, YE Sheng Long and LIU Bin Bin | 1999 | World Journal of Gastroenterology1999，5，2： | 23 |
| 14 | 基于动态Copula的企业集团信用风险传染效应研究显示文摘企业集团成员企业间基于业务关联、技术关联和财务关联的相互联系,构成了企业信用风险传染的重要渠道。金融机构如果缺乏对企业集团成员企业间信用风险传染的管理和防控意识,其后果可能是金融机构信贷资产遭受巨大经济损失。本文基于尾部相依性的视角构建动态协变量Joe-Clayton copula模型,实证分析企业集团成员企业信用风险传染问题。研究发现,信用风险在企业集团成员企业间存在传染效应,且这种信用风险传染效应呈现一定的动态特征;宏观经济因素和微观公司经营能力、财务状况对企业集团内部不同组别子企业间信用风险传染效应的影响从重要性程度和作用方向两个维度上存在差异。 | 周利国 何卓静 蒙天成 | 2019 | 中国管理科学2019，27，2： | 22 |
| 15 | Effect of 5-Aza-2'-deoxycytidine on the P16 tumor suppressor gene in hepatocellular carcinoma cell line HepG2显示文摘INTRODUCTIONHepatocellular carcinoma (HCC) is one of the mostcommon human malignancies worldwide[1,2], and isclosely associated with infection of HBV and HCVand contamination of aflatoxin B1[3-6]. Althoughthe molecular mechanisms of hepatocarcinogenesisremain poorly understood, an increasing number ofgenetic abnormalities have been recognized[7-10],for example, the p16 gene[11,12] the p53gene[13-18], the E-cadherin gene[19], and the c-mycgene[20]. | Li Hua Liu1 Wen Hua Xiao2 Wei Wen Liu3 1Department of Oncology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China (now working in Department of Gastroenterology, General Hospital of PLA, Lanzhou 730050, Gansu Province, China)2Department of Oncology3Department of Gastroenterology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China | 2001 | World Journal of Gastroenterology2001，7，1： | 21 |
| 16 | p16 gene methylation in colorectal cancers associated with Duke's staging显示文摘AIM To explore the association of methylation of the CpG island in the promotor of the p16 tumor suppressor gene with the clinicopathological characteristics of the colorectal cancers.``METHODS Methylation-specific PCR (MSP) was used to detect p16 methylation of 62 sporadic colorectal cancer specimens.``RESULTS pi6 methylation was detected in 42% of the tumors. Dukes staging was associated with p16methylation status, p16 methylation occurred more frequently in Dukes C and D patients (75.9%) than in Dukes A and B patients (12.1%).``CONCLUSION p16 rnethylation plays a role in the carcinogenesis of a subset of colorectal cancer, and it might be linked to poor prognosis. | Jing Yi~1 Zhi-Wei Wang~1 Hui Cang~1 Yu-Ying Chen~1 Ren Zhao~2 Bao-Ming Yu~2 Xue-Ming Tang~1 1 Department of Cell Biology,2 Department of Surgery,Ruijin Hospital,Shanghai Second Medical University,Shanghai 200025,China | 2001 | World Journal of Gastroenterology2001，7，5： | 21 |
| 17 | EXISTENCE AND UNIQUENESS OF SMOOTH SOLUTION FOR SYSTEM OF FERROMAGNETIC CHAIN显示文摘In this paper, we are going to consider the initial value problem with periodic boundarycondition and the Cauchy problem associated with the system of ferromagnetic chain withthe Gilbert damping term Zt=-εZ×(Z×Zzz+Z×Zzz, (ε≥0).The existence of a unique smooth solution is established by using the technique of spatialdifference and crucial a priori estimates of higher-order derivatives in Sobolev spaces. | 周毓麟 郭柏灵 谭绍滨 | 1991 | Science China Mathematics1991，34，3： | 21 |
| 18 | Fluctuations in butyrate-producing bacteria in ulcerative colitis patients of North India显示文摘AIM: To study the interplay between butyrate concentration and butyrate-producing bacteria in fecal samples of ulcerative colitis (UC) patients vs control individuals. METHODS: Fecal samples were collected from 14 control individuals (hemorrhoid patients only) and 26 UC patients (severe: n = 12, moderate: n = 6, remission: n = 8), recruited by the gastroenterologist at the Department of Gastroenterology, All India Institute of Medical Sciences, New Delhi, India. Disease activity in UC patients was determined by clinical colitis activity index. We employed fluorescent in situ hybridization in combination with flow cytometry to enumerate the clostridium cluster population targeted by 16S rRNA gene probe. Major butyrate-producing species within this cluster were quantified to see if any change existed in control vs UC patients with different disease activity. This observed change was further validated by quantitative polymerase chain reaction. In addition to this,we carried out gas chromatography to evaluate the changes in concentration of major short chain fatty acids (SCFAs), namely acetate, n -butyrate, iso -butyrate, in the above samples. Student t test and Graph pad prism-6 were used to compare the data statistically. RESULTS: There was a significant decrease of Clostridium coccoides (control, 25.69% ± 1.62% vs severe, 9.8% ± 2.4%, P = 0.0001) and Clostridium leptum clusters (control, 13.74% ± 1.05% vs severe, 6.2% ± 1.8%, P = 0.0001) in fecal samples of UC patients. Furthermore, we demonstrated that some butyrateproducing members of the clostridial cluster, like Fecalibacterium prausnitzii (control, 11.66% ± 1.55% vs severe, 6.01% ± 1.6%, P = 0.0001) and Roseburia intestinalis (control, 14.48% ± 1.52% vs severe, 9% ± 1.83%, P = 0.02) were differentially present in patients with different disease activity. In addition, we also demonstrated decreased concentrations of fecal SCFAs, especially of n -butyrate (control, 24.32 ± 1.86 mmol/μL vs severe, 12.74 ± 2.75 mmol/μL, P = 0.003), iso -butyrate (control, 1.70 ± 0.41 mmol/μL vs severe, 0.68 ± 0.24 mmol/μL, P = 0.0441) and acetate (control, 39.51 ± 1.76 mmol/μL vs severe, 32.12 ± 2.95 mmol/ μL,P = 0.047), in the fecal samples of UC patients. The observed decrease of predominant butyrate producers of clostridial clusters correlated with the reduced SCFA levels in active UC patients. This was further confirmed by the restoration in the population of some butyrate producers with simultaneous increase in the level of SCFA in remission samples. CONCLUSION: Our observations indicate that decreases in members of the clostridial cluster resulting in reduced butyrate levels contribute to the etiology of UC. | Reena Kumari Vineet Ahuja Jaishree Paul | 2013 | World Journal of Gastroenterology2013，19，22： | 21 |
| 19 | Grinding temperature and energy ratio coefficient in MQL grinding of high-temperature nickel-base alloy by using different vegetable oils as base oil显示文摘Vegetable oil can be used as a base oil in minimal quantity of lubrication(MQL). This study compared the performances of MQL grinding by using castor oil, soybean oil, rapeseed oil, corn oil, sunflower oil, peanut oil, and palm oil as base oils. A K-P36 numerical-control precision surface grinder was used to perform plain grinding on a workpiece material with a high-temperature nickel base alloy. A YDM–III 99 three-dimensional dynamometer was used to measure grinding force,and a clip-type thermocouple was used to determine grinding temperature. The grinding force, grinding temperature, and energy ratio coefficient of MQL grinding were compared among the seven vegetable oil types. Results revealed that(1) castor oil-based MQL grinding yields the lowest grinding force but exhibits the highest grinding temperature and energy ratio coefficient;(2) palm oil-based MQL grinding generates the second lowest grinding force but shows the lowest grinding temperature and energy ratio coefficient;(3) MQL grinding based on the five other vegetable oils produces similar grinding forces, grinding temperatures, and energy ratio coefficients, with values ranging between those of castor oil and palm oil;(4) viscosity significantly influences grinding force and grinding temperature to a greater extent than fatty acid varieties and contents in vegetable oils;(5) although more viscous vegetable oil exhibits greater lubrication and significantly lower grinding force than less viscous vegetable oil, high viscosity reduces the heat exchange capability of vegetable oil and thus yields a high grinding temperature;(6) saturated fatty acid is a more efficient lubricant than unsaturated fatty acid; and(7) a short carbon chain transfers heat more effectively than a long carbon chain. Palm oil is the optimum base oil of MQL grinding, and this base oil yields 26.98 N tangential grinding force,87.10 N normal grinding force, 119.6 °C grinding temperature, and 42.7% energy ratio coefficient. | Li Benkai Li Changhe Zhang Yanbin Wang Yaogang Jia Dongzhou Yang Min | 2016 | Chinese Journal of Aeronautics2016，29，4： | 20 |
| 20 | 改良SDS法快速提取小样品量棉花总DNA及其纯化显示文摘 | 郭宝生 张辉 耿军义 张香云 | 2005 | 棉花学报2005，17，5： | 19 |
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