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Design and analysis of a class of redundant collaborative manipulators with 2-dimension large rotational

Xiaodong JIN, Yuefa FANG, Dan ZHANG, Xueling LUO

《机械工程前沿（英文）》 2020年 第15卷 第1期   页码 66-80 doi: 10.1007/s11465-019-0570-x

摘要： The parallel spindle heads with high rotational capability are demanded in the area of multi-axis machine tools and 3D printers. This paper focuses on designing a class of 2R1T (R: Rotation; T: Translation) parallel spindle heads and the corresponding collaborative 5-axis manipulators with 2-dimension (2D) large rotational angles. In order to construct 2D rotational degrees of freedom (DOF), a platform with 2-dimension revolute joints is proposed first. Based on the constraint screw theory, the feasible limbs that can be connected in the platform are synthesized. In order to provide constant rotational axis for the platform, a class of redundant limbs are designed. A class of redundant 2R1T parallel spindle heads is obtained by connecting the redundant limbs with the platform and the redundant characteristics are verified by the modified Grübler-Kutzbach criterion. The corresponding 5-axis collaborative manipulators are presented by constructing a 2-DOF series translational bottom moving platform. The inverse kinematics and the orientation workspace as well as the decoupling characteristics of this type of 2R1T parallel spindle heads are analyzed. The results show that these manipulators have large 2D rotational angles than the traditional A3/Z3 heads and can be potentially used in the application of multi-axis machine tools and the 3D printers.

关键词： parallel mechanism     redundant mechanism     large rotational angles     machine tools     2R1T spindle head     collaborative manipulator    

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Basic consideration of research strategies for head and neck cancer

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 339-353 doi: 10.1007/s11684-012-0213-7

摘要：

Head and neck cancer (HNC) consists of a group of malignancies affecting closely related anatomical regions of the upper aerodigestive tract (UADT), including the oral cavity, salivary glands, upper and lower jaw bones and facial skin; the nasal cavity, paranasal sinuses, pharynx, larynx and thyroid gland (although the latter is often excluded and considered as part of endocrine neoplasms). Of these, 90% of HNCs are histologically squamous cell carcinomas originating from the mucosal lining. These malignancies are strongly associated with certain environmental and life-style risk factors, principally tobacco in both smoked and smokeless forms, excessive alcohol consumption, diets poor in antioxidants and essential micronutrients, UV light, chemicals used in certain workplaces, and viruses, principally certain strains of human papillomavirus (HPV) and Epstein-Barr virus (EBV). These cancers are frequently aggressive in their biological behaviour with local invasion and metastasis to lymph nodes in the neck. Since most patients are already at late stages of disease at the time of diagnosis, the desirable practice of early diagnosis (first sign of the malignant lesion at an initial stage ) and early treatment, a critical priority to save lives and retain quality of life, is difficult to implement. Thus, primary prevention has been set as a key goal. This article aims to reinforce the basic knowledge of aetiology, key risk factors related to the development of head and neck cancer, basic features of clinical appearance of this group of cancers, and strategies for prevention and early detection. We also suggest basic research strategies on the basis of current knowledge, which should ultimately lead to the improvement of clinical management.

关键词： clinical management     head and neck cancer     prevention and early detection     research strategies     risk factors    

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适于低成本嵌入式硬件的2R-1C模型非迭代参数估计 Article

Mitar SIMIĆ, Zdenka BABIĆ, Vladimir RISOJEVIĆ, Goran M. STOJANOVIĆ

《信息与电子工程前沿（英文）》 2020年 第21卷 第3期   页码 476-490 doi: 10.1631/FITEE.1900112

摘要： 2R-1C模型的参数估计常运用需要高性能处理单元的迭代方法，从而激励我们研究更省时且更节能的参数估计方法。这些低复杂度的算法将更适于便携式微机设备的运行。运用一组封闭表达式从测量阻抗的实部和虚部计算2R-1C模型的参数。对仿真和测量获得的模型阻抗数据作对比分析；结果表明，相较于我们早前提出的非迭代参数估计方法（NIPE），QINIPE能减少80%测量点，且所有估计参数的相对估计误差低于1%。此外，比较了QINIPE和复杂非线性最小二乘法（CNLS）对2R-1C模型参数的估计。结果表明，虽然QINIPE估计精度稍低于CNLS，其依然适合许多实际应用，且运行时间降至原来的1/45至1/30。

关键词： 2R-1C模型；嵌入式系统；参数估计；非迭代方法；二次型    

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A multi-scale model for CO

R. WEI, V. RUDOLPH, C. T. WEI, Y. QIN

《化学科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 20-25 doi: 10.1007/s11705-009-0138-0

摘要： This paper presents a multi-scale model to simulate the multicomponent gas diffusion and flow in bulk coals for CO sequestration enhanced coalbed methane recovery. The model is developed based on a bi-dispersed structure model by assuming that coal consists of microporous micro-particles, meso/macro-pores and open microfractures. The bi-disperse diffusion theory and the Maxwell-Stefan approach were incorporated in the model, providing an improved simulation of the CH —CO /CH —N counter diffusion dynamics. In the model, the counter diffusion process is numerically coupled with the flow of the mixture gases occurring within macro-pores or fractures in coal so as to account for the interaction between diffusion and flow in gas transport through coals. The model was validated by both experimental data from literature and our CO flush tests, and shows an excellent agreement with the experiments. The results reveal that the gas diffusivities, in particular the micro-pore diffusivities are strongly concentration-dependent.

关键词： multi-scale model     gas transport     coal     coalbed methane     CO2 sequestration    

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Expression pattern and regulation of head-to-head genes

Xinxing CUI,Chunhong YANG,Li KANG,Guiyu ZHU,Qingqing WEI,Yunliang JIANG

《农业科学与工程前沿（英文）》 2014年 第1卷 第2期   页码 130-136 doi: 10.15302/J-FASE-2014013

摘要： Vacuolar protein sorting 36 (VPS36), a protein primarily known for its role in the Endosomal Sorting Complex Required for Transport pathway, has recently been shown to be linked to chicken reproduction. Previous research showed that is significantly downregulated in sexually mature chicken ovaries compared to immature ones. In this study, using real-time quantitative RT-PCR, we investigated the expression pattern of and its head-to-head gene mRNA in chicken follicles. Small white follicles were found to have significantly higher expression of and mRNA than any other sized follicles ( <0.05). The expression of and mRNA were detected in both granulosa and theca layers of pre-ovulatory follicles, the expression of in theca layers was slightly higher than in granulosa cells. Treatment of small yellow follicles with follicle-stimulating hormone and estradiol resulted in a marked decrease of both and mRNA ( <0.05); however, progesterone, transforming growth factor-β 1 and luteinizing hormone induced no significant changes in and mRNA expression in these follicles. These results indicate that the head-to-head genes of and exhibit similar expression in chicken follicles and are involved in chicken follicle development.

关键词： chicken     Vps36     Ckap2     mRNA     follicle    

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Screening of potential aquatic probiotics from the major microflora of guppies (

Aparna BALAKRISHNA, T. R. KEERTHI

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 163-173 doi: 10.1007/s11705-012-1283-4

摘要： The fish ( ) was used as the source for probiotics. 46 bacterial isolates were obtained from the skin, gills, guts and intestines of the guppy, (collected from a government model fish farm in Kottayam, India). Of the above isolated strains, four isolates were selected based on their inhibitory spectrum against five indicator strains, 1739, 3906, 2495, 1271 and 1424 (standard cultures collected from Microbial Type Culture Collection (MTCC) Chandigarh, India). Among the resulting isolates, two were gram-positive cocci, namely MBTU-PB2 and MBTU-PB3 and belong to the genus . The other two were gram-negative rods, namely MBTU-PB1 and MBTU-PB4, of the genera and , respectively. The basic probiotic characteristics of these isolates such as the production of bacteriocin like inhibitory substances (BLIS), antibiotic sensitivities and growth profiles were also determined. The above four isolated strains exhibited different antagonisms than the five indicator strains. During incubation, the antibacterial activity gradually increased in the inhibition zone and was influenced by the lag period ( ) and doubling time. The lag periods for most of the four selected strains were shorter than those of the indicator strains and the isolates had different growth rates ( ) than the indicator strains. All four isolates produced BLIS, however, the strains had different BLIS activities against the indicator strains. Treatment of the neutralized cell free supernatants of the selected isolates with proteases eliminated or reduced the BLIS activity, suggesting a proteinaceous nature of the inhibitory compounds. Further, the optimum BLIS activity was observed at neutral pH after 18 h of incubation. The antibiotic sensitivity assay revealed that the isolates were susceptible to routinely used antibiotics, whereas the plasmid profiles showed that the plasmids had no role in the antagonistic properties of the four isolated strains. The results showed that the isolates could be a promising source for biocontrol agents in aquacultures.

关键词： aquaculture     normal flora     immunomodulatory effect     probiotic     antagonistic principle     bacteriocin like inhibitory substances    

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Modeling of alkali-silica reaction in concrete: a review

PAN, Y.T. FENG, J.T. WANG, Q.C. SUN, C.H. ZHANG, D.R.J. OWEN

《结构与土木工程前沿（英文）》 2012年 第6卷 第1期   页码 1-18 doi: 10.1007/s11709-012-0141-2

摘要： This paper presents a comprehensive review of modeling of alkali-silica reaction (ASR) in concrete. Such modeling is essential for investigating the chemical expansion mechanism and the subsequent influence on the mechanical aspects of the material. The concept of ASR and the mechanism of expansion are first outlined, and the state-of-the-art of modeling for ASR, the focus of the paper, is then presented in detail. The modeling includes theoretical approaches, meso- and macroscopic models for ASR analysis. The theoretical approaches dealt with the chemical reaction mechanism and were used for predicting pessimum size of aggregate. Mesoscopic models have attempted to explain the mechanism of mechanical deterioration of ASR-affected concrete at material scale. The macroscopic models, chemo-mechanical coupling models, have been generally developed by combining the chemical reaction kinetics with linear or nonlinear mechanical constitutive, and were applied to reproduce and predict the long-term behavior of structures suffering from ASR. Finally, a conclusion and discussion of the modeling are given.

关键词： alkali-silica reaction (ASR)     modeling     concrete     mesoscopic     macroscopic    

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Optimization of cellulase production using

Saravanan P, Muthuvelayudham R, Rajesh Kannan R, Viruthagiri T

《化学科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 443-452 doi: 10.1007/s11705-012-1225-1

摘要： The potential of for cellulase production using pineapple waste as substrate has been investigated. A maximum cellulase activity of 9.23 U/mL is obtained under the optimum experimental conditions: pH (5.5), temperature (37.5°C), initial substrate concentration (3%), inoculum concentration (6.6 × 10 ?CFU/mL), and culture time (6 days). Box-Behnken design (BBD) statistical tool and genetic algorithm (GA) are used to optimize the process parameters. The BBD study of linear and quadratic interactive effects of experimental variables on the desired response of cellulase activity showed that the second order polynomial is significant ( = 0.9414). The experimental cellulase activity under the optimal conditions identified by the BBD is 9.23 U/mL and that by GA is 6.98 U/mL. This result indicates that the BBD model gives better result than GA in the present case.

关键词： cellulase     pineapple waste     Trichoderma reesei     Box-Behnken design     genetic algorithm    

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A novel flow electrode capacitive deionization device with spindle-shaped desalting chamber

《环境科学与工程前沿（英文）》 2023年 第18卷 第4期 doi: 10.1007/s11783-024-1800-y

摘要：

● A spindle-shaped influent chamber was designed and equipped in FCDI system.

关键词： Spindle-shaped chamber     Desalination performance     Flow electrode capacitive deionization    

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Chidamide inhibits the NOTCH1-MYC signaling axis in T-cell acute lymphoblastic leukemia

《医学前沿（英文）》 2022年 第16卷 第3期   页码 442-458 doi: 10.1007/s11684-021-0877-y

摘要： T-cell acute lymphoblastic leukemia (T-ALL) is one of the most dangerous hematological malignancies, with high tumor heterogeneity and poor prognosis. More than 60% of T-ALL patients carry NOTCH1 gene mutations, leading to abnormal expression of downstream target genes and aberrant activation of various signaling pathways. We found that chidamide, an HDAC inhibitor, exerts an antitumor effect on T-ALL cell lines and primary cells including an anti-NOTCH1 activity. In particular, chidamide inhibits the NOTCH1-MYC signaling axis by down-regulating the level of the intracellular form of NOTCH1 (NICD1) as well as MYC, partly through their ubiquitination and degradation by the proteasome pathway. We also report here the preliminary results of our clinical trial supporting that a treatment by chidamide reduces minimal residual disease (MRD) in patients and is well tolerated. Our results highlight the effectiveness and safety of chidamide in the treatment of T-ALL patients, including those with NOTCH1 mutations and open the way to a new therapeutic strategy for these patients.

关键词： T-cell acute lymphoblastic leukemia     HDAC inhibitor     chidamide     NOTCH1     MYC     ubiquitination    

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Techno-economic evaluation of a biogas-based oxidative coupling of methane process for ethylene production

Alberto T. Penteado, Mijin Kim, Hamid R. Godini, Erik Esche, Jens-Uwe Repke

《化学科学与工程前沿（英文）》 2018年 第12卷 第4期   页码 598-618 doi: 10.1007/s11705-018-1752-5

摘要：

This contribution is a preliminary techno-economic assessment of a biogas-based oxidative coupling of methane (OCM) process. Biogas is frequently utilized as a renewable energy source within small scale combined heat and power plants or as a natural gas substitute. The activation of methane also enables its utilization as a feedstock to produce chemicals. In this sense, the OCM process allows for the direct conversion of methane into ethylene, which is a major building block for the chemical and polymer industries. Biogas resulting from the anaerobic digestion of vinasse, a liquid effluent from bioethanol industry, is treated for contaminant removal and its methane content is converted into ethylene, which is then purified as the main product. The biogas cleaning process is assessed based on literature data, while an experimentally validated simulation model is used to assess the OCM process. A techno-economic evaluation is then performed through a Monte Carlo simulation, wherein uncertain parameters take random values between reasonable bounds. The net present value results positive in 74% of the cases, indicating that the project is profitable under a wide range of scenarios. Some performance improvement opportunities have been identified and highlighted to guide future studies in the topic.

关键词： biogas conversion     ethylene production     oxidative coupling of methane     feasibility study    

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Treatment technologies for aqueous perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA)

VECITIS, Hyunwoong PARK, Jie CHENG, Brian T. MADER, Michael R. HOFFMANN

《环境科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 129-151 doi: 10.1007/s11783-009-0022-7

摘要： Fluorochemicals (FCs) are oxidatively recalcitrant, environmentally persistent, and resistant to most conventional treatment technologies. FCs have unique physiochemical properties derived from fluorine which is the most electronegative element. Perfluorooctanesulfonate (PFOS), and perfluorooctanoate (PFOA) have been detected globally in the hydrosphere, atmosphere and biosphere. Reducing treatment technologies such as reverses osmosis, nano-filtration and activated carbon can? remove ?FCs ?from ?water. ?However,? incineration ?of the concentrated waste is required for complete FC destruction. Recently, a number of alternative technologies for FC decomposition have been reported. The FC degradation technologies span a wide range of chemical processes including direct photolysis, photocatalytic oxidation, photochemical oxidation, photochemical reduction, thermally-induced reduction, and sonochemical pyrolysis. This paper reviews these FC degradation technologies in terms of kinetics, mechanism, energetic cost, and applicability. The optimal PFOS/PFOA treatment method is strongly dependent upon the FC concentration, background organic and metal concentration, and available degradation time.

关键词： fluorochemical (FC) degradation technologies     perfluoroctanesulfonate (PFOS)     perfluorooctanoate     (PFOA)     oxidation     reduction     photolysis     thermolysis     review    

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Influence and related mechanism of Retn gene expression on glucose uptake in 3T3-L1 cells

LI Yahui, DONG Shiyuan, YU Chao, JIANG Yu, LI Huaixing, SUN Shuhan

《医学前沿（英文）》 2007年 第1卷 第3期   页码 269-273 doi: 10.1007/s11684-007-0051-1

摘要： The aim of this article was to investigate the influence and the related mechanism of the gene on glucose uptake and insulin resistance in 3T3-L1 cells. Radioimmunoassay was used to determine glucose uptake in 3T3-L1 cells with different gene expression levels, whether cells were stimulated by insulin or not. RT-PCR and real-time RT-PCR analysis were used to determine the mRNA levels of several glucose transport proteins in 3T3-L1 cells with different gene expression levels, including insulin receptor substrate-1(IRS-1), phosphatidylinositol 3-kinase (PI-3K), AKT-2, glucose transporter-4 (GLUT-4), p38 mitogen-activated protein kinase (p38MAPK) and glycogen synthase kinase-3b (GSK-3). The glucose uptake decreased with the increase in gene expression in 3T3-L1 cells, which was independent of whether the cells were stimulated by insulin or not. The mRNA expression of two signal proteins PI-3K and AKT-2 decreased and the other two signal proteins, GSK-3 and p38MAPK, increased with overexpression in 3T3-L1 cells. Resistin could induce insulin resistance in adipocytes, which might be related to the changes of some proteins in PI-3K and Ras pathways.

关键词： 3T3-L1     influence     resistance     receptor substrate-1     transport    

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Association of SIPA1 545 C>T polymorphism with survival in Chinese women with metastatic breast cancer

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 138-142 doi: 10.1007/s11684-013-0247-5

摘要：

It has been demonstrated that single nucleotide polymorphisms (SNPs) of SIPA1 (signal-induced proliferation associated gene 1) are associated with metastatic efficiency in both human and rodents. The purpose of this study was to determine whether SIPA1 545 C>T polymorphism was associated with overall survival in patients with metastatic breast cancer. In this study, SIPA1 545 C>T polymorphism was detected in 185 metastatic breast cancer patients using polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP). Survival curves for patients with SIPA1 545 C>T polymorphism was compared using the Kaplan-Meier method with log-rank tests. We found that SIPA1 545 C>T polymorphism was significantly associated with survival in 185 patients with metastatic breast cancer. Patients with SIPA1545 T/T genotype had a significantly worse overall survival (OS) than did patients with C/T or C/C genotype (50.0% vs. 62.9%, P = 0.042). Moreover, in multivariate analysis, as compared with the C/C or C/T genotype, the T/T genotype remained an independent unfavorable prognostic marker of OS in this cohort (hazard ratio [HR] = 2.16; 95% CI= 1.12–4.15; P = 0.022). Our findings indicate that metastatic breast cancer patients with SIPA1 545 T/T genotype have a poorer survival compared to patients with C/C or C/T genotype.

关键词： SIPA1     polymorphism     metastatic breast cancer     survival    

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Effect on proliferation and apoptosis of T24 cell lines via silencing DNMT1 with RNA interference

ZHANG Shilong, ZENG Fuqing, PENG Shibo, WANG Liang

《医学前沿（英文）》 2008年 第2卷 第4期   页码 374-379 doi: 10.1007/s11684-008-0072-4

摘要： Expression of DNA methyltransferase 1 (DNMT1), which plays an important role on aberrantly methylated CpG in the promoter regions of tumor suppressor genes (TSGs), is higher in bladder cancer cells than in normal bladder cells. Therefore, its overexpression is closely related to tumor formation. In this study, the eukaryotic vector pshRNA-DNMT1 was constructed and transfected into T24 cells. Levels of DNMT1 mRNA and protein were detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blot. Relative to the blank control at the 24th, 48th and 72nd hour after transfection of pshRNA-DNMT1, the inhibitory rates of DNMT1 mRNA levels in T24 cells were 28.44%, 52.48%, 70.91%, respectively. Those of DNMT1 proteins were 24.27%, 57.79%, and 77.74%, respectively. Proliferation and apoptosis were assayed by MTT and flow cytometry with Annexin-V-FITC/PI staining. The growth inhibition rates of pshRNA-DNMT1 at the 24th, 48th and 72nd hour after transfection of pshRNA-DNMT1 were (4.34 ± 0.76)%, (9.87 ± 1.54)% and (13.78 ± 1.93)%, respectively. There were statistically significant differences between pshRNA-DNMT1 and the control blank at each time points ( < 0.01); 24, 48 and 72 hours after T24 cells were transfected by pshRNA-DNMT1, the apoptosis rates of pshRNA-DNMT1 were (3.87 ± 0.81)%, (8.69 ± 1.23)% and (11.46 ± 1.24)%, respectively ( < 0.01 blank control). Based on this case, our conclusion is that the recombinant plasmid pshRNA-DNMT1 can silence the expression of gene DNMT1 mRNA and protein effectively, and to some extent, it also can inhibit the proliferation of bladder cancer cell and promote the cellular apoptosis.
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标题 作者 时间 类型 操作

Design and analysis of a class of redundant collaborative manipulators with 2-dimension large rotational

Xiaodong JIN, Yuefa FANG, Dan ZHANG, Xueling LUO

期刊论文

Basic consideration of research strategies for head and neck cancer

null

期刊论文

适于低成本嵌入式硬件的2R-1C模型非迭代参数估计

Mitar SIMIĆ, Zdenka BABIĆ, Vladimir RISOJEVIĆ, Goran M. STOJANOVIĆ

期刊论文

A multi-scale model for CO

R. WEI, V. RUDOLPH, C. T. WEI, Y. QIN

期刊论文

Expression pattern and regulation of head-to-head genes

Xinxing CUI,Chunhong YANG,Li KANG,Guiyu ZHU,Qingqing WEI,Yunliang JIANG

期刊论文

Screening of potential aquatic probiotics from the major microflora of guppies (

Aparna BALAKRISHNA, T. R. KEERTHI

期刊论文

Modeling of alkali-silica reaction in concrete: a review

PAN, Y.T. FENG, J.T. WANG, Q.C. SUN, C.H. ZHANG, D.R.J. OWEN

期刊论文

Optimization of cellulase production using

Saravanan P, Muthuvelayudham R, Rajesh Kannan R, Viruthagiri T

期刊论文

A novel flow electrode capacitive deionization device with spindle-shaped desalting chamber

期刊论文

Chidamide inhibits the NOTCH1-MYC signaling axis in T-cell acute lymphoblastic leukemia

期刊论文

Techno-economic evaluation of a biogas-based oxidative coupling of methane process for ethylene production

Alberto T. Penteado, Mijin Kim, Hamid R. Godini, Erik Esche, Jens-Uwe Repke

期刊论文

Treatment technologies for aqueous perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA)

VECITIS, Hyunwoong PARK, Jie CHENG, Brian T. MADER, Michael R. HOFFMANN

期刊论文

Influence and related mechanism of Retn gene expression on glucose uptake in 3T3-L1 cells

LI Yahui, DONG Shiyuan, YU Chao, JIANG Yu, LI Huaixing, SUN Shuhan

期刊论文

Association of SIPA1 545 C>T polymorphism with survival in Chinese women with metastatic breast cancer

null

期刊论文

Effect on proliferation and apoptosis of T24 cell lines via silencing DNMT1 with RNA interference

ZHANG Shilong, ZENG Fuqing, PENG Shibo, WANG Liang

期刊论文