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Aging Kinetics in a CuNiSiCr Alloy

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Journal of Materials Science & Technology 2004年第6期20卷 727-730页

作者： JingguoLEI pingliu XiaotianJING DongmeiZHAO JinliangHUANG CollegeofMaterial Xi′anUniversityofTechnologyXi′an710048China MaterialsScienceandEngineeringCollege HenanUniversityofScienceandTechnologyLuoyang471003China

The aging precipitation behavior in solution treated Cu-Ni-Si-Cr alloy has been studied in terms of the analyses of the variations in electrical conductivity. On the basis of the linear relationship between the electrical conductivity and the volume fraction of the precipitates, the phase transformation kinetics equation was deduced from the Avrami empiricai formula. On the basis of this equation, transformation kinetics curves corresponding to 5% and 50% transformation were established.

关键词： Cu-Ni-Si-Cr alloy Aging precipitation Electrical resistivity Volume fraction Transformation kinetics

Kinetic equation for internal oxidation of Cu-Al alloy cylinders

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Journal of University of Science and Technology Beijing 2005年第3期12卷 262-266页

作者： KexingSong JiandongXing BaohongTian pingliu QimingDong SchoolofMaterialsScienceandEngineering HenanUniversityofScienceandTechnologyLuoyang471003China StateKeyLaboratoryforMechanicalBehaviorofMaterials Xi＇anJiaotongUniversityXi＇an710049China／／SchoolofMaterialsScienceandEngineeringHenanUniversityofScienceandTechnologyLuoyang471003China StateKeyLaboratoryforMechanicalBehaviorofMaterials Xi＇anJiaotongUniversityXi＇an710049China

The kinetics of internal oxidation of Cu-Al alloy cylinders, containing up to 2.214mol% Al, were investigated in the temperature range of 1023 K to 1273 K, and the depth of internal oxidation was measured in the microscopy. A kinetic equation was derived to describe the internal oxidation of Cu-Al alloy cylinders. For the internal oxidation of Cu-Al alloys employed in the synthesis of alumina dispersion strengthened copper, the kinetic equation can be simplified. The derived equation was checked experimentally by means of oxidation depth measurements and the results show that the derived equation is exact enough to describe the kinetics of internal oxidation of Cu-Al alloy cylinders. Based on this equation and the oxidation depth measurements, the permeability of oxygen in solid copper was obtained. Investigation also shows that there is no evidence for preferential diffusion along grain boundaries in the process of internal oxidation.

关键词： kinetic equation cylinder Cu-Al alloys internal oxidation

Prediction of Properties in Thermomechanically Treated Cu-Cr-Zr Alloy by an Artificial Neural Network

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Journal of Materials Science & Technology 2003年第6期19卷 529-532页

作者： JuanhuaSU QimingDONG pingliu HejunLI BuxiKANG CollegeofMaterialsScienceandEngineering NorthwesternPolytechnicalUniversityXi'an710072China CollegeofMaterialsEngineering HenanUniversityofScienceandTechnologyLuoyang471003China

A supervised artificial neural network (ANN) to model the nonlinear relationship between parameters of thermomechanical treatment processes with respect to hardness and conductivity properties was proposed for Cu-Cr-Zr alloy. The improved model was developed by the Levenberg-Marquardt training algorithm. A basic repository on the domain knowledge of thermomechanical treatment processes is established via sufficient data acquisition by the network. The results showed that the ANN system is an effective way and can be successfully used to predict and analyze the properties of Cu-Cr-Zr alloy.

关键词： Cu-Cr-Zr alloy Thermomechanical treatment Levenberg-Marquardt algorithm,Artificial neural network

Microstructural Changes of Cu-Ni-Si Alloy during Aging

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Journal of Materials Science & Technology 2004年第1期20卷 99-102页

作者： QimingDONG DongmeiZHAO pingliu BuxiKANG JinliangHUANG DepartmentofMaterialsEngineering HenanUniversityofScienceandTechnologyLuoyang471003China DepartmentofScientificResearch LuoyangUniversityLuoyang471000China

Age hardening in Cu-3.2Ni-0.75Si (wt pct) and Cu-1.0Ni-0.25Si (wt pct) alloys from 723 to 823 K is studied. After an incubation period strengthening appears which is due to precipitates in the ***-0.25Si (wt pct) alloy. On other hand an immediate increase of the yield strength characterizes the aging of the alloy. This is followed by the regions of constant yield strength and further by a peak. The microstructure of the alloy was studied by, means of transmission electron microscope (TEM) and X-ray diffraction (XRD). Spinodal decomposition takes place followed by nucleation of the ordering coherent (Cu,Ni)3Si particles, further precipitation annealing coherent δ-Ni2Si nucleated within the (Cu,Ni)3Si particle. Any change of the yield strength can be described by an adequate change of the structure in the sample. The nature of the aging curves with a 'plateau' is discussed. The formulas of Ashby and Labusch can be used to explain the precipitation.

关键词： Copper alloy Transformation Ageing Spinodal decomposition Ordering Yield strength

Tissue distribution and excretion of ^(125)I-lidamycin in mice and rats

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World Journal of Gastroenterology 2005年第21期11卷 3281-3284页

作者： You-pingliu Quan-ShengLi Yu-RongHuang Chang-XiaoLiu NationalKeyLaboratoryofPharmacokineticsandPharmacodynamics TianjinInstituteofPharmaceuticalResearch308An-ShanWestRoadTianjin300193China LaboratoryofDrugMetabolismPharmacokinetics ShenyangPharmaceuticalUniversity103WenhuaRoadShenyang110016LiaoningProvinceChina NationalKeyLaboratoryofPharmacokineticsandPharmacodynamics TianjinInstituteofPharmaceuticalResearchTianjin300193China

AIM: To investigate the tissue distribution, urinary and fecal excretions of 125I-lidamycin (125I-C-1027) in mice and its biliary excretion in rats. METHODS:The total radioactivity assay (RA method) and the radioactivity assay after precipitation with 200 mL/L trichloroacetic add (TCA-RA method) were used to dete-rmine the tissue distribution,and the urinary and fecal excretions of 125I-C-1027 in mice and its biliary excretion in rats. RESULTS:Tissue concentrations reached the peak at the fifth minute after administration of 125I-C-1027 to mice. The highest concentration was in kidney, and the lowest in brain at all test-time points. The organs of the concentrations of 125I-C-1027 from high to low were kidney, lung, liver, stomach, spleen, uterus, ovary, intestine, muscle, heart, testis, fat, and brain in mice. The accumulative excretion amounts of 0-24 h, and 0-96 h after administration of 125I-C-1027 were 68.36 and 71.64% in urine, and 2.60 and 3.21% in feces of mice, respectively, and the accumulative excretion amount of 0-24 h was 3.57% in bile in rats. CONCLUSION: Our results reflect the characteristics of the tissue distribution, urinary and fecal excretions of 125I-C-1027 in mice and the biliary excretion of 125I-C-1027 and its metabolites in rats, and indicate that 125I-C-1027 and its metabolites are mainly distributed in kidney, and excreted in urine.

关键词： Distribution Excretion Lidamycin C-1027 RA method TCA-RA method

Expression and localization of Smadl, Smad2 and Smad4 proteins in rat testis during postnatal development

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Asian Journal of Andrology 2003年第1期5卷 51-55页

作者： JingHU Yuan-QiangZHANG Xin-pingliu Rui-AnWANG YanJIN Ruo-JunXU DepartmentofHistologyandEmbryology DepartmentofBiochemistryandMolecularBiology DepartmentofOralHistologyandPathology SchoolofDentistryFourthMilitaryMedicalUniversityXi‘an710032China DepartmentofZoology UniversityofHongKongHongKongHKSARChina

Aim: To study the expression and regulation of Smadl, Smad2 and Smad4 proteins (intracellular signaling molecules of transforming growth factor-β family) in rat testis during postnatal development. Methods: The whole testes were collected from SD rats aged 3, 7, 14, 28 and 90 (adult) days. The cellular localization and developmental changes were examined by immunohistochemistry ABC method with the glucose oxidase-DAB-nickel enhancement technique. Quantitative analysis of the immunostaining was made by the image analysis system. The Smads proteins coexistence in the adult rat testis was tested by the double immune staining for CD14-Smad4 and Smad2-Smad4. The protein expression of Smad during rat testicular development was examined by means of Western blots. Results: Smadl, Smad2 and Smad4 were present throughout testicular development. The immunostaining of Smadl and Smad2 were present in spermatogenic cells. A positive immunoreactivity was located at the cytoplasm, but the nucleus was negative. Smadl was immunolocalized at the d14, d28 and adult testes, while Smad2, at the d7, d14, d28 and adult testis. There was positive irnmunoreaction in the Sertoli cells and Leydig cells as well. The immunolocalization of Smad4 was exclusively at the cytoplasm of Leydig cells and the nuclei were negative throughout the testicular development. No expression was detected in the germ cells. The results of image and statistical analysis showed that generally the expression of Smadl, Smad2 and Smad4 in the testis tended to increase gradually with the growth of the rat. Conclusion: The present data provide direct evidences for the molecular mechanism of TGF-βaction in rat testes during postnatal development and spermatogenesis.

关键词： TGF-β Smadl Smad2 Smad4 testis

Primary Malignant Lymphoma of the Breast： a Study of 15 Cases and Review of the Chinese Literature

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Chinese Journal of Clinical Oncology 2004年第4期1卷 269-272页

作者： ChunhongHu LiqiangZhou pingliu DepartmentofOncology XiangyaSecondHospitalofCentralSouthernUniversityChangsha410011China DepartmentofMedicalOncology CancerHospitalChineseAcademyofMedicalSciencesPekingUnionMedicalCollegeBejing100021China

OBJECTIVE To study the clinical features and significant prognostic factors for primary breast lymphoma (PBL).METHODS A retrospective clinical analysis of 15 patients with PBL and a statistical analysis of 134 cases with PBL were *** All 15 patients, but one, were female with a median age of 42years. None were diagnosed with PBL preoperatively. Pathological studyshowed that all cases were non-Hodgkin's lymphoma with the DLCL type(53.3%). The right breast was affected in 10 patients, the left in 4 and both inone. A statistical analysis showed that the size of tumors and treatmentpattern (single or multi-modality) were significant prognostic factors inpredicting the survival time, but the location of the tumor at initialpresentation and the age of the patients were *** Most PBLs are NHL. The right breast is more frequently involved. The correct diagnosis depends mostly on postoperative pathology. The size of the tumor and the modality of treatment are significant prognostic factors.

关键词：初级恶性淋巴瘤肿瘤胸部临床研究病例报告 NHL

Significance of glucocorticoid receptor expression in colonic mucosal cells of patients with ulcerative colitis

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World Journal of Gastroenterology 2005年第12期11卷 1775-1778页

作者： HuZhang QinOuyang Zhong-HuiWen ClaudioFiocchi Wei-pingliu Dai-YunChen Feng-YuanLi DepartmentofGastroenterology SichuanUniversityWestChinaHospitalChengdu610041SichuanProvinceChina DivisionofGastroenterology UniversityHospitalofClevelandCaseWesternReserveUniversitySchoolofMedicineClevelandOhioUSA DepartmentofPathology SichuanUniversityWestChinaHospitalChengdu610041SichuanProvinceChina

AIM: Glucocorticoid (GC) resistant ulcerative colitis (UC) remains a serious disease and is difficult to manage. Although the molecular basis of GC insensitivity is still unknown, GC receptors (GRAAA and GRp) may play an important role in it. This study was aimed to investigate the relationship between the expression of GRa and GRp in colonic mucosal cells of patients with UC, the efficacy of GC therapy and the intensity of inflammation. METHODS: Twenty-five cases of UC were classified into: GC sensitive (n = 16) and GC resistant (n - 9) cases. Patients consisted of mild (n = 6), moderate (n = 8) and severe (n = 11) cases. GRa and GRp expression in colonic mucosal specimens were investigated by immunohistochemistry, and compared between GC resistant and sensitive groups, and also among various degrees of inflammation. RESULTS: All cases were positive for GRa and GRp expression. Both positive association between GRa expression and the response of UC to GC and strong negative association between GRp expression and the response of UC to GC were identified. There was no significant association between GRa/GRp expression and the degree of inflammation of UC. CONCLUSION: These findings suggest that both GRa and GRp may play an important role in the action of GC, and that GRp functions as a dominant negative inhibitor of GRa. Expression of GRa and GRp in colonic mucosal cells of patients with UC may serve as predictors of glucocorticoid response, but can not function as markers of inflammatory intensity.

关键词： Glucocorticoid Ulcerative colitis

Effects of STI571 and p27 gene clone on proliferation and apoptosis of K562 cells

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World Journal of Gastroenterology 2005年第14期11卷 2130-2135页

作者： WeiWang Li-BoYao Xin-pingliu QIFeng Zhen-ChuanShang Yun-XinCao Bing-ZhongSun DepartmentofHematology XijingHospitalTheFourthMilitaryMedicalUniversityXi'an710032ShaanxiProvinceChina DepartmentofBiochemistryandMolecularBiology TheFourthMilitaryMedicalUniversityXi'an710032ShaanxiProvinceChina DepartmentofImmunology TheFourthMilitaryMedicalUniversityXi'an710032ShaanxiProvinceChina

AIM: To investigate the combined effect of STI571 and p27 gene clone on the regulation of proliferation, cell cycle and apoptosis of K562 cell ***: p27 gene was obtained by RT-PCR, and its sequence was approved to be correct. Then p27-pcDNA3.1 vector was constructed and transfected into K562 cell line.p27-pcDNA3.1-K562 cell clone was screened by G418 after transfection, p27 protein was identified by Western *** was used to detect the survival rate of the cell. Flow cytometry was used to detect cell cycle and apoptosis ***: The expression of p27 protein could be detected by Western blot in p27-pcDNA3.1-K562 cells. A strong inhibition of cell proliferation was observed in p27-pcDNA3.1-K562 cells as compared with that of the control (pcDNA3.1-K562 cells). The cells at G0/G1 phase were significantly increased, and cells at S phase were greatly *** apoptosis index was increased greatly after p27-pcDNA3.1-K562 cells were treated with STI571, and survival rate of the cell was markedly declined (0.35-0.58,P<0.05-0.048 vs STI571-K562 cell, 0.35-0.72, P<0.01-0.001 vs p27-K562 cell).CONCLUSION: p27 and STI571 have a synergistic action on inhibition of proliferation and induction of apoptosis on K562 cells.

关键词： STI571 p27 Gene clone