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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 253-262页

作者： ZHANG Qingqing ZHANG Qingwu LU Hao WANG Wei fang tian LIU Hongying LIU Jiaji WANG Shuangshuang School of Chemical&Environmental Engineering China University of Mining&TechnologyBeijing 100083China

A systematic investigation of the graphene oxide composite reduced by either p-phenylenediamine oligomers or hydrazine hydrate was performed with field emission scanning electron microscopy,high resolution transmission electron microscopy,X-ray diffraction,fourier transform infrared,and X-ray photoelectron spectroscopy *** electrical capacitance of the composite was evaluated by a cyclic voltammetry technique,while the properties of these prototype supercapacitors were measured by a chronopotentiometry *** was found that,under the solvothermal condition,the graphene oxide reduced by p-phenylenediamine oligomers was observed to have higher electrical capacitance than that reduced by *** improved electrical capacitance can be attributed to that p-phenylenediamine oligomers are the more effective spacers for graphene layers;and they could also provide some pseudo-capacitance to the graphene oxide composite based on their conjugate *** results imply that graphene oxide modified by diamine oligomers has a good potential in energy storage devices.

关键词： oligomers p-phenylenediamine graphene oxide hydrazine supercapacitors

Relationships between endothelial nitric oxide synthase gene polymorphisms and osteoporosis in postmenopausal women

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第8期10卷 609-618页

作者： Shun-zhi LIU Hong YAN Wei-kun HOU Peng XU Juan tian Li-fang tian Bo-feng ZHU Jie MA She-min LU Department of Public Health School of Medicine Xi 'an Jiaotong University Xi 'an 710061 China Key Laboratory of Environment and Genes Related to Diseases of Ministry of Education Xi 'an Jiaotong University Xi 'an 710061 China Department of Genetics and Molecular Biology School of Medicine Xi 'an Jiaotong University Xi 'an 710061 China Department of Bone and Joint Diseases of Xi 'an Red Cross Hospital Xi 'an 710054 China Department of Forensic Medicine School of Medicine Xi 'an Jiaotong University Xi'an 710061 China

Objective： To investigate the relationships between endothelial nitric oxide synthases （eNOS） G894T and 27 bpvariable number tandem repeat （VNTR） gene polymorphisms and osteoporosis in the postmenopausal women of Chinese Han nationality. Methods： In the present study, 281 postmenopausal women from Xi＇an urban area in West China were recruited, and divided into osteoporosis, osteopenia, and normal groups according to the diagnostic criteria of osteoporosis proposed by World Health Organization （WHO）. The bone mineral density （BMD） values of lumbar vertebrae and left hips were determined by QDR-2000 dual energy X-ray absorptiometry. Blood samples were tested for plasma biochemical indicators including testosterone, estradiol, calcitonin, osteocalcin, and procollagen type I amino-terminal propeptide by enzyme-linked immunosorbent assay （ELISA）, tartrate-resistant acid phosphatase by spectrophotometric method, and the content of nitric oxide by Griess method. Genome DNA was extracted from whole blood, and G894T polymorphism of eNOS gene was analyzed by using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） method and 27 bp-VNTR polymorphism of eNOS gene was genotyped by PCR method. Then the relationships between genotypes and biochemical indicators, genotypes and osteoporosis, and haplotypes and osteoporosis were analyzed. Results： The average BMD values of the femoral neck, ward＇s triangle and lumbar vertebrae 1-4 （LI-L4） in the subjects with T/T genotype in eNOS G894T locus were significantly higher than those in the subjects with G/T and G/G genotypes （P〈0.05）. The average BMD of the femoral neck in the subjects with a/a genotype of eNOS 27 bp-VNTR locus was evidently higher than that in the subjects with b/b genotype （P〈0.05）. The plasma testosterone and osteocalcin concentrations in the subjects of eNOS G894T G/T genotype were evidently higher than those in the subjects of other genotypes （P〈0.05）; the plasma estradiol concentration in

关键词： Postmenopausal women Osteoporosis Endothelial nitric oxide synthase Gene polymorphisms Bone mineral density

Biological effects of low-energy C ion implantation on sesame(Sesamum indicum L.)

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Frontiers in Biology 2007年第2期2卷 184-186页

作者： ZHANG Lan JIA Hanchao fang tian ZHOU Yunlong SU Ying College of Life Science Beijing Normal UniversityBeijing100875China Institute of Low-energy Nuclear Physics Beijing Normal UniversityBeijing100875China

Field cultivation experiments on white sesame(Sesamum indicum L.)seeds implanted with low-energy C ion showed that different dosages of C ion implantation pro-duce different biological *** plants in 6 different dosage groups with C ion density respectively at 1×10^(11),1×10^(12),1×10^(15),5×10^(15),1×10^(16),5×10^(16)ion/cm2 were superior to the control group in plant height,leaf number,stalk diameter and leaf ***,sesame plants in these groups flower and seed earlier than those in the control group,and single plant yield also *** all the groups,the 5×10^(15)ion/cm2 dosage group yielded the best effect,whereas the 1×10^(17)/cm^(2)dosage group showed an evident inhibitory effect of ion implantation on the germination and growth of the sesame seeds.

关键词： low-energy C ion ion implantation white sesame(Sesamum indicum L.) biological effects

Clinical Characteristics,Diagnosis,and Therapeutics of COVID-19:A Review

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Current Medical Science 2023年第6期43卷 1066-1074页

作者： Na-na XIE Wen-cong ZHANG Jia CHEN fang-bing tian Jian-xin SONG Department of Infectious Diseases Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)that suddenly emerged at the end of December 2019 and caused coronavirus disease 2019(COVID-19)continues to afflict humanity,not only seriously affecting healthcare systems but also leading to global social and economic *** of August 2022,there were approximately 580 million confirmed cases of COVID-19 and approximately 6.4 million confirmed deaths due to this *** data are sufficient to highlight the seriousness of SARS-CoV-2 *** most patients with COVID-19 present primarily with respiratory symptoms,an increasing number of extrapulmonary systemic symptoms and manifestations have been associated with *** the outbreak of COVID-19,much has been learned about the disease and its causative ***,great effort has been aimed at developing treatments and drug interventions to treat and reduce the incidence of *** this narrative review,we provide a brief overview of the epidemiology,mechanisms,clinical manifestations,diagnosis,and therapeutics of COVID-19.

关键词： coronavirus disease 2019 severe acute respiratory syndrome coronavirus 2 mechanism clinical manifestations diagnosis therapeutics

The Ephemeral 10β-OH Trifluoromethanesulfonates of 7-Epi Paclitaxel Analogs─A New Example for Anchimeric Assistance

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Chinese Chemical Letters 1998年第1期9卷 29-33页

作者： Wei Shuo fang Qi Cheng fang and Xiao tian LIANG (Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050 ) Chinese Acad Med Sci Inst Mat Med Beijing 100050 Peoples R China Peking Union Med Coll Beijing 100050 Peoples R China

Two rearranged products, dienone 4 and 10-oxo product 5 were obtained upon attempted 10β-OSO2SO2CF3 formation from 3. The formation of compound 5 can be explained by anchimeric assistance of 7α-OH. Reduction of 4 ... 详细信息

关键词： rearrange anchimeric assistance neighboring group participation

The priority of management factors for reducing the yield gap of summer maize in the north of Huang-Huai-Hai region, China

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Journal of Integrative Agriculture 2021年第2期20卷 450-459页

作者： LIU Yue-e LI Yu-xin LU tian-fang XING Jin-feng XU tian-jun CAI Wan-tao ZHANG Yong ZHAO Jiuran WANG Rong-huan Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding Maize Research CenterBeijing Academy of Agriculture&Forestry SciencesBeijing 100097P.R.China

Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity(CK), farmer practice(FP), high yield and high efficiency(HH), and super high yield(SH), to estimate the yield gap. Different factorial experiments(fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha^(–1), respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors(contribution rates) were plant density(13.29%)>fertilizer(11.95%)>hybrids(8.19%)>irrigation(4%) for FP to HH, and hybrids(8.94%)>plant density(4.84%)>fertilizer(1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH.

关键词： maize yield gap management factors priority hybrid plant density fertilizer irrigation

Students’Perceptions of Online Education During the COVID-19 Pandemic

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Psychology Research 2023年第9期13卷 414-419页

作者： fang tian Huazhong University of Science and Technology WuhanChina

The COVID-19 pandemic forced many universities around the world to move their educational activities onto online *** conducted a survey in which asking undergraduates at a Chinese university how they felt about different aspects of online education during the *** received responses from 1,088 students.A majority of the students(67.9%)thought that physical classroom is better than online education and *** students believed that teachers have improved their ability to teach online since the pandemic(67.3%)and online teaching is a suitable option in the current situation(65.8%).The students expressed satisfaction with the online educational resources and teachers’flexible use of online ***,the students felt that online education is stressful and affecting their health and social *** pandemic has led to widespread use of online education,and we hope that online education can be better in the future.

关键词： assessment content delivery COVID-19 health interaction online education social life

Comparison of ocular biometric parameters between two swept-source optical coherence tomography devices and Scheimpflug tomography in patients with cataract

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1437-1446页

作者： Shan Ma Cheng Li Jing Sun Jun Yang Kai Wen Xi-Teng Chen fang-Yu Zhao Rong-Yu Gao fang tian tianjin Key Laboratory of Retinal Functions and Diseases Tianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300380China Zhengda Guangming Eye Group Weifang 261000Shandong ProvinceChina Binzhou Polytechnic Binzhou 256603Shandong ProvinceChina

AIM:To assess and compare the variations and agreements across different ocular biometric parameters using swept-source optical coherence tomography(SS-OCT)and Scheimpflug tomography in patients diagnosed with ***:This prospective case series was conducted at tianjin Medical University Eye *** total,212 eyes from 212 patients scheduled for phacoemulsification were *** were evaluated preoperatively using two SSOCT devices(IOLMaster700 and CASIA2)and Scheimpflug tomography(Pentacam).Central corneal thickness(CCT),anterior chamber depth(ACD),aqueous depth(AQD),white-to-white distance(WTW),flat simulated keratometry(Kf),steep simulated keratometry(Ks),mean keratometry(Km),and total corneal keratometry(TKm)were *** correlation coefficient(ICC),95%confidence intervals(CI)and limits of agreement(LoA)widths were conducted to assess differences and correlations between ***:All parameters,except for Ks,were significantly *** comparison revealed no significant differences between keratometry obtained by IOLMaster 700 and *** widths of all paired comparisons for Ks were>0.80 *** for WTW between IOLMaster 700 and CASIA2 and between CASIA2 and Pentacam,other Pearson’s coefficients between devices showed a strong correlation(all r>0.95).The ICC of WTW(ICC=0.438,95%CI 0.167-0.625)showed poor *** reliability of CCT,ACD,and AQD was excellent(all ICC>0.95),whereas that of TKm was good(ICC=0.827,95%CI 0.221-0.939).A significant linear correlation was also observed among ***:The ocular parameters derived from the use of IOLMaster700,CASIA2,and Pentacam exhibit significant discrepancies;as such,measurements from these devices should not be deemed as interchangeable.

关键词： ocular parameters swept-source optical coherence tomography cataract

Individual Variation in Growth in Sea Cucumber Apostichopus japonicus(Selenck) Housed Individually

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Journal of Ocean University of China 2010年第3期9卷 291-296页

作者： LIANG Miao DONG Shuanglin GAO Qinfeng WANG fang tian Xiangli The Key Laboratory of Mariculture Ministry of Education Ocean University of China Qingdao 266003 P. R. China

The exceptionally large individual growth variation has been previously recognized in several sea cucumber cohorts. However, there is a lack of information regarding the mechanism of such individual differences. In this study, the sea cucumber Apostichopusjaponicus （Selenka） was reared individually in order to eliminate possible effects of social interaction, stocking density, etc. The results showed that there were substantial differences in growth among the sea cucumber individuals during the 100-day experiment. The special growth rate of the sea cucumber individuals differed by up to three folds （from 0.40% to 1.01%）, and the coefficient of variation in body weight increased from 12.04% to 40.51%. The final wet body weight, food intake and food conversion efficiency for each sea cucumber were generally positively correlated with their initial wet body weight （P〈0.05）. Energy budget of the animals showed that the food energy spent on respiration was much greater （about four folds） but energy deposited for growth was much less for （initially） smaller than for larger A. japonicus. The present result implies that there are obvious genetic differences among the sea cucumber individuals, largely accounting for the individual growth variation of the cohort sea cucumber. These results will provide some basic data for promoting selective breeding and fanning of the sea cucumber.

关键词： sea cucumber Apostichopusjaponicus growth coefficient of variation individual

Preliminary Studies on Acylation of 10β-OH and 7α-OH in 7-Epi-10-deacetylpaclitaxel

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Chinese Chemical Letters 1997年第10期8卷 847-848页

作者： Wei Shuo fang Qi Cheng fang and Xiao tian LIANG (Institute of Materia Medica , Chinese Academy of Medical Sciences & Peking Union Medical College.Beijing 100050) CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA BEIJING UNION MED COLL BEIJING 100050PEOPLES R CHINA

10β-OH can be acylated cleanly when 7α-OH is also free, and thus a facile access to semisynthesis of 7-epi-paclitaxel was proposed. A 2's, 3's-oxazoline paclitaxel analog was serendipitously synthesized

关键词： OH in 7-Epi-10-deacetylpaclitaxel TES Preliminary Studies on Acylation of 10