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Upper Bainite Formation Mechanism in Fe-1.36Si-1.01Cr-0.88C Steel

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Journal of Materials Science & Technology 1998年第1期14卷 62-64页

作者： Liu, QS Peng, HF Gu, nj Hebei Univ Technol Tianjin 300132 Peoples R China

In this paper it is-discussed on the mechanism of upper bainite formation. According to the results obtained in Fe-1.36Si-1.01Cr-0.88C steel, we discovered that the primary upper bainite is formed by subunits arranging along its long axis and steps are formed by subunits growing into different size-along the thickness, the macro-plane of the primary upper bainite plate is the same as the basal plane (shear plane), the formation mechanism of the primary upper bainite plate is the nucleation-growth mechanism of subunits shearing one by one along long axis, controlled by diffusion.

关键词： Steel

Sintering Formation of Low Temperature Phase MnBi and Its Disordering in Mechanical Milling

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Journal of Materials Science & Technology 1996年第5期12卷 335-341页

作者： Yin, FX Gu, nj Shigematsu, T Nakanishi, N KONAN UNIV FAC SCIDEPT CHEMKOBE 658JAPAN

With X-ray diffraction and DSC analysis, it is found that 4 cycles of sintering at 593 K are necessary for the complete production of the low-temperature phase (LTP) MnBi. The c/a of the fabricated LTP MnBi is 1.4286. Metastable phase MnBip formed in primary sintering stage of LTP MnBi has the similar crystal structure and lattice constant with the quenched high-temperature phase (HTP) Mn1.08Bi. The structural differences between MnBip phase and Mn1.08Bi phase are discussed. The LTP MnBi phase is unstable for strong mechanical milling as Bi appears after milling over 7200 s in the present milling condition. Strains caused by the mechanical attrition are difficult to accumulate in the MnBi crystals, and the crystal size of the milled MnBi is only 30 nm before the presence of grains coalescence. The whole milling process can be classified into 3 stages indicated by the structural changes. Based on the structural parameter calculation, the changes of atomic configurations in every stage have been discussed. The existence of Bi equivalent vacancy site is considered to play an important role in the disordering processes of Mn and Bi atoms.

关键词： Binary alloys

Antitrypanosomal potentials of the extract and fractions of Abrus precatorius seeds

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Asian Pacific Journal of Tropical Medicine 2012年第11期5卷 857-861页

作者： Nwodo nj Nwodo OFC Department of Pharmaceutical Chemistry University of NigeriaNsukka Nigeria Department of Biochemistry University of NigeriaNsukka Nigeria

Objective:To evaluate the in vivo trypanocidal activity of the methanol extract and fractions of Abrus precatorius seeds in ***:Parasiteamia was induced unto mice by intraperitoneal injection of 1.25×105 Trypanosoma in normal *** days when a high level of parasiteamia was established treatment commenced until ten *** mice were treated with 10,20 and 40 mg/kg *** the extract and 5 and 10 mg/kg *** the fraction（F2）,respectively for 5 *** acelurate at the dose of 3.5 mg/kg *** two days was used as the reference *** level of parasitaemia and packed cell volume（PCV） of the animals estimated. Results:At doses of 10,20 and 40 mg/kg the crude extract showed a sharp reduction in the level of parasitaemia in mice compared with the untreated *** mice treated with F,at doses of 5 and 10 mg/kg showed a sharp reduction in the level of parasitamia to zero in day 9,and a gradual recovery from the 12th day of *** effect is comparable to that of the mice treated with 7 mg/kg of standard drug diminazene *** PCV of the treated showed a gradual decrease with time,but not as much as the untreated *** screening revealed the presence of glycosides,alkaloids,carbohydrates,tannins and proteins in the Abrus precatorius powder while F2 was rich in ***:This study shows that both the extract and the fractions of Abrus precatorius seeds exhibited a promising trypanocidal *** may be responsible for the observed activity.

关键词： Abrus precatorius Seed extract Trypanocidal effect Parasiteamia Fractions Trypanosome brucei brucei Berenil

Clarithromycin resistance in Helicobacter pylori and its clinical relevance

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World Journal of Gastroenterology 1999年第3期5卷 263-266页

作者： Xia HX Fan XG Talley nj Univ Sydney Dept Med Nepean Hosp Penrith NSW 2751 Australia Hunan Med Univ Xiang Ya Hosp Dept Infect Dis Changsha Peoples R China

TRODUCTIONThe macrolide clarithromycin has emerged as the most important antibiotic in combined therapy for eradication of H. Pylori infection［1,2］. However, concerns about increasing clarithromycin resistance in H. Pylori and its impact on the efficacy of eradication therapy have been raised since its widespread acceptance in H. Pylori therapy［3,4］. Here, we sought to review the geographic prevalence of clarithromycin resistance in H. Pylori and its molecular mechanisms, and assess the clinical relevance of clarithromycin resistance.

关键词： PCR Clarithromycin resistance in Helicobacter pylori and its clinical relevance

Aging Effect on Configuration of Dislocations in Parent Phase of a Thermomechanically Trained Cu-Zn-Al Alloy

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Journal of Materials Science & Technology 1995年第6期11卷 415-417页

作者： ZHANG, QG GAO, JS GU, nj YIN, FX HEBEI INST TECHNOL TIANJIN 300130PEOPLES R CHINA

With electron microscopic investigation, the configuration of dislocations in an aged Cu-25.72Zn-4.21Al (wt-%) shape memory alloy was found to be in the form of superdislocations and their jogs, which were different from the preferential dislocations regularly aligned in an unaged alloy. These defects generated during aging treatment were considered to be responsible for low fatigue life.

关键词： Copper alloys

Localization of HCV RNA and capsid protein in human hepatocellular carcinoma

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World Journal of Gastroenterology 2000年第1期6卷 136-137页

作者： Dai YM Shou ZP Ni CR Wang nj Zhang SP Department of Pathology Second Military Medical UniversityShanghai 200433China

INTRODUCTIONThe relation of HCV to hepatocytic carcinoma(HCC) has been emphasized recently in low HBVinfection countries and *** distributionpatterns of HCV in liver tissues are not wellunderstood although studies on ... 详细信息

关键词： Subject headings hepatitis C virus liver neoplasms carcinoma hepatocellular in situ hybridization immunohistochemistry

In vitro-in vivo studies on anti-trypanosomal potentials of Zapoteca portoricensis

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Asian Pacific Journal of Tropical Medicine 2009年第1期2卷 25-29页

作者： Nwodo nj Omeje EO Bran R Department of Pharmaceutical Chemistry University of NigeriaNsukkaNigeria Department of Medical Parasitology and Infection Biology Swiss Tropical InstituteCH-4002 BaselSwitzerland

Objective:Aqueous extracts of Zapoteca portoricensis are used traditionally as antidiarrhea agent and in the treatment of diverse gastrointestinal disorders here in Nigeria specifically,the southern ***,the aqueous extract of the plant is also used traditionally as anticonvulsant,antispasmodic and in the treatment of *** too,the anti-inflammatory and antimicrobial activities of the methanol extracts of the root of Zapoteca portoricensis was *** this research,we are set to investigate the trypanocidal activity of Zapoteca ***:The methanol extract of the root of Zapoteca portoricensis was investigated for both in vitro and in vivo trypanocidal activity following established *** summary,phytochemical analysis was carried out on both the crude powdered root and on the methanol extract following standard procedures. The oral acute toxicity test(LD50 ) of the crude methanol extract was determined according to the method described by Lorke（1983）.Albino mice（17g-21g） of either sex were *** methanol extract was suspended in 3%v/v tween 85 and administered orally at doses of 10 mg/kg,100 mg/kg and 1 000 mg/kg to three groups of mice（n = 3 ）.The animals were observed for 24 *** on the result obtained in this initial test,doses of 4 mg/kg,6 mg/kg,and 8 mg/kg were administered to three different *** LD50 was calculated as the geometric mean of the lowest dose killing a mouse and the highest dose showing no *** invivo /in-vitro antitrypanosomal evaluations were carried out in experimental animals and tissue cell culture respectively. Results:The result of the in vitro studies shows the inhibitive concentration-50（IC-50） against Trypanosoma brucei rhodesiense（***） to be 0.372 mg/kg,while the control drug melarsoprol was 0.006 mg/*** Trypanosoma brucei brucei（***）,the IC-50 is 6.42 mg/kg against 0.87 of the reference drug *** cytotoxicity on L-6 c

关键词： Zapoteca portoricensis Trypanocidal effects T.b.rhodensiense T.cruzi In vitro/in vivo model

肾髓质过表达鞘氨醇1-磷酸受体1转基因可减轻醋酸脱氧皮质酮-盐诱导的高血压

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中华高血压杂志(中英文) 2024年第8期 800-800页

作者： Hu G Xie DP Chen C Wang WL Li PL Ritter JK Li nj 袁源练桂丽

前期研究表明,肾髓质鞘氨醇1-磷酸受体1(sphingosine-1-phosphate receptor 1,S1PR1)介导钠排泄,高盐摄入可增加S1PR1水平,醋酸脱氧皮质酮(deoxycorticosterone acetate,DOCA)可阻断高盐诱导的肾髓质S1PR1,在集合管中敲除S1PR1可加重DOCA盐诱导的高血压。该研究验证在肾髓质中过表达S1PR1基因是否可减轻DOCA-盐小鼠模型的钠潴留和高血压。方法:给雄性C57BL/6J小鼠肾髓质转染对照或表达S1PR1的质粒后予DOCA-盐处理。

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Anti-ulcer potentials of phylum mollusca(tropical snail)slime

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Asian Pacific Journal of Tropical Medicine 2009年第3期2卷 23-28页

作者： Nwodo nj Okonta J M Ezugwu CO Attama AA Faculty of Pharmaceutical Sciences University of NigeriaNsukka410001Enugu State

Objective:The effectiveness of the slimy substance in snail to regenerate and repair damaged areas on it body/shell lead to this ***:The anti-ulcer’property of snail slime extracted from phylur mollusca(tropical snail) from the giant African snail Archachatina marginata(***) was investi gated using histamine,stress and indomethacin-induced *** solubility profile of extract was investiga ted in different solvents and at different *** analysis was carried out to determine the type of constituents present in the slim,while acute toxicity test was carried out to evaluate its profile of toxicity The effect of the snail slim on gastrointestinal motility was investigated in mice,while the guinea pig ileum wa used to study the effect of the extract on contraction produced by acetylcholine and *** snail slim contained copious quantity of protein,with varying amounts of simple sugars,carbohydrates and *** slime was not soluble in most common solvents and increases in temperature,did not appear to increase its sol ***:The result further indicated that although the snail slime exhibited significant(P<0.05) an ti -ulcer induced by stress and histamine,it was most potent against ulcer induced by *** snai slime potently inhibited gastrointestinal movement in mice in a dose-dependent manner;however,it was not a ble to inhibit contraction induced by acetylcholine and histamine in guinea pig ***:The snai mucin possesses potent antiulcer properties without any toxic *** mechanism responsible for the anti-ul cer property may not be postulated with certainty but cytoprotective and anti-spasmodic activities are most likel to be involved.

关键词： Anti-ulcer activity Phylum moliusca Snail slime