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Both postprandial hyperlipidemia and hyperinsulinemia have been thought to play an important role in the development of atherosclerosis, and to be a potent risk factor for cardiovascular event. To examine effects of glycemic state on postprandial hyperlipidemia and hyperinsulinemia in patients with coronary artery disease (CAD), a total of 112 consecutive male pati ents with angiographically confirmed CAD were loaded with a high-fat and high-glucose test meal. CAD patients were divided into three groups as “non-diabetic”, “prediabetic”, and “diabetic” CAD groups. The serum triglyceride (TG) and remnant-like particle cholesterol (RLP-C) levels at the 6th hour in diabetic CAD group showed significantly higher than non-diabetic CAD group, and the incremental area under the curves (iAUCs) of these levels in diabetic CAD group were significantly greater than non-diabetic CAD group (TG, P = 0.0194; RLP-C, P = 0.0219). There were no significant differences in the iAUCs of TG or RLP-C between prediabetic and non-diabetic CAD group. The AUCs of plasma insulin levels or insulin resistance index (IRI): (AUCs of insulin) × (AUCs of glucose) as the insulin resistance marker were greater in diabetic CAD group than non-diabetic CAD group (insulin, P = 0.0373; IRI, P = 0.0228). The AUCs of serum TG or RLP-C levels showed a correlation with the AUCs of plasma insulin (AUC-TG, r = 0.5437, P

A 68-year-old female was presented with claudication in the left lower leg. She underwent angiography with carbon dioxide (CO2) because she had a history of anaphylactic shock to iodinated contrast medium. It revealed total occlusion of the left superficial femoral artery (SFA), and subsequently endovascular therapy (EVT) was performed by an antegrade approach from the left common femoral artery. After stent implantation, we performed optical frequency domain imaging (OFDI) using CO2 as contrast medium. OFDI has been extensively studied in the coronary circulation; however, its use in the peripheral arterial circulation is scarce. We present a case of stent implantation and OFDI using CO2 as an ancillary tool during EVT for SFA lesions in the patient with contraindication to iodinated contrast medium.

A 65-year-old man with occlusion of the left superficial femoral artery (SFA) underwent the endovascular therapy (EVT). A successful EVT was performed with three paclitaxel-eluting peripheral stents (Zilver PTX®) implanted in the left SFA. Angiography 1 year later showed an exudation of contrast outside the stent struts, and intravascular ultrasound, and optical coherence tomography also showed incomplete stent apposition with remarkable positive vascular remodeling. Zilver PTX® stent is a polymer-free stent and it is unclear that the reason why the patient treated with Zilver PTX® stents in the SFA lesions caused the contrast stainings outside the stents. However, we need more careful long-term follow-up of this patient for late thrombosis.

A 67-year-old man with recent myocardial infarction underwent a total of five sirolimus-eluting stents (SES) implantation for three vessels stage by stage. A follow-up angiography showed no significant restenosis except one in the side branch. Thereafter, he had remained asymptomatic. Sixty-six months later, he had an acute myocardial infarction with cardiogenic shock due to simultaneous 3-vessel very late stent thrombosis (VLST). After successful percutaneous coronary intervention, final angiography revealed serious peri-stent contrast staining along with positive remodeling and grade V stent fracture. This rare case illustrates simultaneous 3-vessel VLST, associating with multiple SES-related problems, under continuation of aspirin and cilostazol.

We have performed a series of experiments to observe 11 Stark-induced E1 transitions from the 15650.55 cm-1 level to higher levels with odd parity in samarium (Sm) with optical double-resonance technique. Five Stark-induced E1 transition to the 28233.08, 28613.22, 28913.97, 29041.31 and 29130.03 cm-1 levels have been observed. In order to investigate the contributors to the Stark-induced E1 transition, we have measured scalar and tensor polarizabilities for the observed Stark-induced E1 transitions. Clear Stark splittings were observed for the levels 28233.08 and 28613.22 cm-1, and their tensor polarizabilities were determined for each isotope. Scalar polarizabilities were determined for the 28233.08, 28613.22, 28913.97 and 29130.03 cm-1 levels for the first time. Among them, scalar polarizability for the 28233.08 cm-1 level was the largest in magnitude and was 3.60(10) x 103 kHz/(kV/cm)2 for $\hspace{0.1em}^{152}$ Sm. We noticed that both scalar and tensor polarizabilities of the 28233.08 cm-1 level depend on the isotope; the difference of magnitude of the scalar and tensor polarizabilities between $\hspace{0.1em}^{144}$ Sm and $\hspace{0.1em}^{154}$ Sm were remarkably large and were about 10 and 6 percent, respectively.

We describe a 47-year-old woman with severe aplastic anemia with genital bleeding who developed acute severe hepatitis after the administration of danazol while she was receiving cyclosporin. She had been diagnosed with severe aplastic anemia 1 year previously and, while hospitalized, had received methyl prednisolone pulse therapy, which was not successful. She was then referred to our hospital. She was treated with antithymocyte globulin, cyclosporin, granulocyte colony-stimulating factor, and methyl prednisolone; a good response was achieved after 3 months of this therapy. Subsequently, oral administration of cyclosporin was continued, but she was readmitted to our hospital when pancytopenia gradually developed and the genital bleeding recurred. Danazol was administered for pancytopenia and endometriosis. Four days after the first administration of danazol, epigastric pain occurred, and the danazol was stopped. Eighteen days after the first danazol administration, very severe hepatic injury occurred abruptly. The patient died of hepatic failure. Postmortem examination revealed centrilobular massive necrosis of the liver. Danazol was implicated as the agent responsible for causing the hepatic failure. Drug interactions between danazol and cyclosporin may cause adverse effects.

The excitation energies and hyper-fine structure constants of the low-lying levels of Sm atom are calculated using the multi-configuration Dirac-Fock (MCDF) method. The results show that the excitation energies of the ground state multiplets can be calculated accurately using a small orbital set but the higher levels need larger orbital sets. Similar inference can also be drawn from the discrepancy between the calculated values of the hyper-fine constants and the experimental data. A sequence of MCDF calculation demonstrates the effect of the MCDF potential on the orbitals. Among the rare earth atoms Sm is a promising candidate for discrete symmetry violation experiments in atoms. This makes accurate theoretical calculations necessary since parameters in particle physics can be derived by combining the experimental results with the theoretical results. And these could be a probe for the physics beyond the standard model.

The recent introduction of limited resections of the ventral pancreas for benign disease and for low-grade malignancies calls for a thorough understanding of its anatomy. The two embryonic anlagen were characterized and distinguished through a comprehensive study of their macroscopic, histologic, and immunohistochemical characteristics in 20 autopsy specimens before reconstruction. Sections were histologically stained with hematoxylin-eosin and Grimelius and immunohistochemically stained with antibodies to insulin, glucagon, somatostatin, and pancreatic polypeptide by the avidin biotin complex method. The ventral and dorsal anlagen of the pancreas were reconstructed from eight autopsy specimens, using the "macroserial" method, after serial sectioning and immunohistochemical staining with anti-pancreatic polypeptide antibodies. Compared with the dorsal pancreas, the ventral pancreas was characterized by the presence of smaller and more closely packed lobuli, irregular rather than uniform islets of Langerhans, and rich immunostaining with anti-pancreatic polypeptide. Construction of the two anlagen showed that the dorsal pancreas consisted of the anterior part of the head of the pancreas, and the body and tail of the pancreas, while the ventral pancreas consisted of the posterior part of the head of the gland and the upper two-thirds (62.5%) or all (37.5%) of the uncinate process. The ventral pancreas was related to the right lateral surface of the superior mesenteric vein extending to the back. However, it did not extend across the front surface of the superior mesenteric vein to the left as previously described. The uncinate process was also located posterior to but not anterior to the superior mesenteric vein. The contributions of the ventral and dorsal anlagen to the anatomy of the pancreas gland as demonstrated in this study differ, in some relevant features, from the classical descriptions in the medical literature. The current anatomical findings add essential knowledge for the pancreatic surgeon who contemplates tissue-preserving resections.

Systematic study of hyperfine structures, Zeeman and Stark effects in Sm I is performed for the lowest 7G1-6 levels belonging to the configuration 4f 66s6p by atomic-beam laser spectroscopy with fluorescence detection. The hyperfine coupling constants of 7G2-6 levels are determined. From the Zeeman splittings for the 4f 66s 2 7F2-6 − 4f 66s6p 7G2-6 transitions, g-values are determined for the 7G2.6 levels and the precision is improved by several orders of magnitude. From the Stark splittings for the 7F0-3 − 7G1-3 transitions, tensor polarizabilities α 2(J) are determined for the upper 7G1-3 levels. Particularly for the 7G1 level (15 650.55 cm−1) which has close-lying opposite-parity level, the isotope dependence of α 2(J) is clearly observed for the first time.

Atomic-beam laser spectroscopy with fluorescence detection is applied to investigate the hyperfine structure (hfs), Stark and Zeeman effects of the electric dipole transitions of Sm i. The measurements are performed for the four transitions of 0 → 15650.55, 292.58 → 15650.55, 292.58 → 15567.32, and 1489.55 → 16890.59 cm-1. The hfs constants of the upper and lower levels and the isotope shifts of the transitions are determined. The tensor polarizability of the 15650.55 cm-1 level is found to be α2 = -556.2 ± 11.8 kHz/(kV/cm)2. Thanks to the accurate g values of the lower levels [Childs, W.J., Goodman, L.S.: Phys. Rev. A 6, 2011 (1972)], the g values of the upper levels are obtained from the observed Zeeman splittings. The values are found to be -0.115907(79), 2.22259(20) and 1.599968(51) for the 15650.55 cm-1 .1, 15567.32 cm-1 and 16890.59.cm-1 levels, respectively.

To determine whether c-kit and kit ligand (KL) mRNAs could be expressed in human epithelial tumors, reverse transcriptase-polymerase chain reaction and Northern blot analysis were performed. KL mRNA was shown to be expressed in a variety of epithelial tissues and cell lines. The expression of c-kit mRNA was then examined in hepatocellular and colon carcinoma cell lines. While hepatocellular carcinoma cell lines did not express c-kit mRNA as far as we could ascertain, 2 of 5 colon carcinoma cell lines showed the expression of both c-kit and KL mRNAs. Furthermore, the expression of c-kit in these cells was demonstrated at the protein level by flow cytometry. These data suggest that c-kit and KL may play an important role as an autocrine loop in the proliferation of some colon carcinoma cells.

Monoclonal antibodies against cellular components of reticular meshworks were produced by immunizing rats with heterogeneous stromal-cell population of mouse spleen. Immunohistochemical screening selected two antibodies, WP-1 and RPSC-2. WP-1 proved to immunostain the meshwork of the B area densely, leaving the marginal zone unstained; it also reacted sparsely with the meshwork of the T-cell region. In contrast, RPSC-2 selectively immunostained the meshwork of the T region. Immuno-electron microscopy clearly visualized, for both antibodies, reaction products being deposited along the cytomembrane of the fibroblastic reticulum cells, along their abundant cytoplasmic processes that were densely intertwined with lymphocytes. Double immunostaining with RPSC-2 followed by WP-1 clearly divided the white pulp into the T and the B domains. The meshwork in the T-cell region proved to be immunostainable with both WP-1 and RPSC-2. Thus, the fibroblastic reticulum cells of the T- and the B-cell areas, while indistinguishable by routine microscopy, are at least partially heterogeneous.

The ordered alloy phase of Ti3Al shows a rather wide solid solution range in aluminum and also in vanadium. Several Ti-Al-V ternary alloys have been prepared to investigate the alloy composition effect upon microstructure, crystallography, and mechanical characteristics. The materials containing 75, 70, and 65 at.% titanium, and 0 or 5 at.% vanadium were prepared by arc melting. Metallographic observation has revealed that the binary Ti-Al alloys contained somewhat coarse grains with about 100 μm grain diameter. In contrast to this, ternary alloys containing 5 at.% vanadium showed smaller grained microstructures with grain diameters around 15 μm. The grain size could not be adjusted to a unified value in the present study. X-ray diffraction study and microanalysis showed that the alloys contained single phase α2. Not every possible diffraction peak of the D019 ordered structure has been observed in the XRD patterns. The lattice parameters, a and c, were observed to decrease as the aluminum content increased and also when vanadium was added. Compression tests have been performed at various temperature ranging from an ambient temperature up to 1300K on rectangular parallelepiped specimens with 2mm×2mm×3mm dimensions. Alloys containing more aluminum showed higher strength, and vanadium addition enhanced the strength of the alloys. In some alloys deformability and strength are both enhanced by vanadium addition in some alloys. Temperature dependence of strength showed a little variation upon chemical compositions.

Constant stress creep under compression stress, 100 to 316 MPa, at 1100 K was investigated on single-phase TiAl intermetallics. The material was ingot-cast, isothermally forged, and then annealed to produce stable equi-axed grain structures, whose average grain diameters were 25, 42 and 70μm. Creep curves were very similar among the three specimens with different grain diameters and the creep rates at a given strain, as well as the minimum creep rates, depended little on grain size. Two regimes were observed on the stress dependence of the minimum creep rate. The stress exponent under high stresses was about 4.5, independent of grain size. Under stresses lower than about 150 MPa it became about 8.

Fine grained gamma+beta dual phase microstructures were obtained in aluminum-titanium-vanadium ternary alloys containing 40 at.% aluminum and 60 at.% (titanium and vanadium). Average grain size was about 5, 3, and 2 micrometers in the recrystallized materials containing 20, 30, and 40 at.% vanadium, and the phase constitution was around 50vol.% gamma phase and 50vol.% beta phase. Compression behavior was investigated at temperatures ranging from the room temperature up to 1200K, and compressive creep tests were carried out at 1050-1200K in order to characterize the temperature and chemical composition dependences of strength and deformation. These gamma+beta microduplex materials showed very high strength at room temperature; 0.2% proof stress was around 1200MPa. The compression deformability decreased from about 0.2 to 0.05 true strain with increasing vanadium content. The grain size effect was not clarified yet, but it was rather disappointing that smaller-grained material with Al40Ti20V40 composition did not show effective improvement either in strength or in deformability. 0.2% proof stress showed a considerable weakening at temperatures higher than 900K; the onset temperature of softening became lower as the vanadium content increased. In Al40Ti40V20 material with about 5 micrometer grains, both gamma and beta grains were flattened up to 1000K, however, above 1100K the gamma grain showed no significant shape change even after a heavy deformation. This is probably because the gamma grains were relatively stronger than the beta grains. The gamma grains showed tendency toward agglomeration, which is similar to rafting of precipitate particles. Surface relief was observed after high temperature deformation suggesting activity of boundary sliding on grain boundaries and interfaces. Compressive creep behavior was investigated under a constant true stress in vacuum. Creep curves consisted of a small amount of normal primary transient, the minimum creep rate region, and a steady or slightly accelerating creep region. Stress exponent decreased to about 2 with decreasing vanadium content. It was rather unexpected that smaller grained Al40Ti20V40 material showed larger stress exponent around 3.

Compressive creep behavior has been investigated on coarse grained Ti3Al alloys with aluminum contents ranging from 15mol%Al to 42mol%Al, in order to obtain basic information concerning the chemical composition effect on creep of Ti3Al. Pure aluminum and titanium of 99.99% purity were arc-melted into small ingots weighing about 10grams under an argon atmosphere. The resulting microstructures after the hot deformation and vacuum annealing contained equiaxed grains whose average diameter ranged from 125 to 192 micrometers except alloys containing 40 and 42 mol% aluminum.Compressive creep tests were performed in vacuum on parallelepiped specimens with dimensions of 2mm×2mm×3mm. The applied compressive stress was 159MPa, and the test temperature was around 1200K.A very small primary transient and the minimum creep rate region followed by a gradual creep acceleration were observed in the materials containing aluminum up to 25mol%. In contrast to this, the materials containing more aluminum than 25mol% showed greater primary transient where creep deceleration continued up to about 0.1 true strain. Dual phase materials containing the γ phase showed small primary transient probably due to the constraint from the γ phase.

L12 modified titanium trialuminides have been prepared by replacing 9at.% of the aluminum in Al3Ti with chromium and/or iron. The materials were recrystallized into single phase polycrystals after isothermal forging resulting in an average grain diameter of about 40μm. Lattice parameter of the material containing 9 at.% chromium or 9 at.% iron, are 0.3959nm and 0.3939nm, respectively. The lattice parameters varied linearly with composition between these values for additions of both chromium and iron. Uniaxial compression tests were performed at temperatures ranging from 293K to 1300K. The yield strength is not sensitive to chemical composition within the range of compositions tested. Flow stress serrations of a few % were observed at temperatures around 600K, where intermittent drops in flow stress started immediately after yielding and continued to the end. These serrations were observed up to about 800K. At 900K and above the materials became fully deformable. Quasi steady state flow and strain softening were observed at 1200K and 1300K, respectively, due to dynamic recrystallization.

Gastrointestinal hemorrhage is a troublesome complication in patients with hematologic diseases. Gastrointestinal bleeding in patients with acute leukemia may be the result of chemotherapy, coagulopathy, or infection. Herein, we report a case of acute myelogenous leukemia (AML) that developed severe hemorrhage from gastric vascular ectasia (GVE) lesions, which were fully resolved after achieving a complete remission (CR). A possible relationship between AML and the development of GVE was suspected. A 70-year-old man was admitted to our hospital in September 2005, because a diagnosis of acute leukemia was suspected. A few days before admission, he was presented to another hospital because of worsening fatigue and allegedly having tarry stools. He had anemia (hemoglobin concentration was 7.6 g/dL) and severe thrombocytopenia (platelet count was 2000/ L). He was transferred to our hospital after 2 units of packed red blood cells and 15 units of concentrated platelet plasma were transfused. He had a history of acute myocardial infarction at the age of 63. Physical examination disclosed no abnormal findings except for anemia and petechiae in the trunk. A peripheral blood examination revealed that the leukocyte count was 7300/ L with 48% blasts, the hemoglobin concentration was 9.7 g/dL, and the platelet count was 66,000/ L. Liver function test results were normal. Occult blood of the feces was negative. A bone marrow aspiration revealed the proliferation of blasts without maturation in 50.3% of all nucleated cells and in 93.2% of non-erythroid cells. Only a few blasts had Auer rods or azure granules. More than half of the blasts were positive for peroxidase staining. Thus, a diagnosis of AML without maturation (M1 phenotype according to the FrenchAmerican-British classification) was made. The blasts were Severe Hemorrhage from Gastric Vascular Ectasia Developed in a Patient with AML

Trisomy 22 as a sole acquired chromosomal abnormality is an uncommon cytogenetic aberration in hematological malignancies. As far as we know, this abnormality has not been reported in myelodysplastic syndrome (MDS). We report here a unique case of MDS showing trisomy 22 as a sole karyotypic abnormality. An 89-year-old woman was admitted to our hospital in June 2004 because of weakness. She had a history of cerebral infarction at the age of 65. She had anemia that began when she was 80 years old and was diagnosed as being of unknown origin. Physical examination disclosed severe anemia without hepatosplenomegaly or lymphadenopathy. The patient’s temperature was 36.7 C, pulse was 84, and blood pressure was 152/80 mm Hg. Her white cell count was 3.9 109/L, with 64.5% neutrophils, 33.5% lymphocytes, and 2% monocytes. Red cell count was 850 109/L with 1.2% reticulocytes, hematocrit was 8.8%, and hemoglobin concentration was 2.7g/dL. Her platelet count was 323 109/L. A bone marrow aspiration showed hypercellular bone marrow with proliferation of blasts (9.5% of all nucleated cells), decreased erythropoiesis, and trilineage dysplasia. Proliferation of megakaryocytes (4.0% of all nucleated cells) was prominent, and some erythrocytes showed ringed-sideroblastic appearance. A diagnosis of refractory anemia with excess blasts 1 was made according to World Health Organization criteria. Cytogenetic studies of bone marrow cells disclosed 47, XX, +22 [16] (Figure 1), /46, XX [4]. Repeat examination of bone marrow cells a month later showed the same karyotypic abnormality, 47, XX, +22 [16]/46, XX [4]. To detect cryptic rearrangements of major-bcr/abl, PML/RARA, AML1/ MTG8, CBF /MYH11, DEK/CAN, NUP98-HOXA9, MLL/ AF6, MLL-AF9, MLL/AF9, or MLL/ENL, real-time quantitative polymerase chain reaction (RQ-PCR) analyses were performed by SRL (Tokyo, Japan), using their corresponding Trisomy 22 as the Sole Karyotypic Abnormality in Myelodysplastic Syndrome

Titanium trialuminide intermetallic compound Al{sub 3}Ti, is characterized by its low density and its high oxidation resistance. Such properties are potentially useful in light-weight and heat-resistant structures for aerospace applications. Here, the allying effect of vanadium upon {delta}-phase titanium trialuminide has been investigated using materials whose compositions were of the type Al{sub 3}(Ti,V). Six types of ternary aluminum-titanium-vanadium alloys, ranging from Al{sub 3}Ti to Al{sub 3}V at 5 atomic % intervals, have been prepared by arc melting. All the materials showed the DO{sub 22} tetragonal structure, suggesting vanadium atoms substitute titanium atoms. The 0.2% proof stress increased with increasing vanadium content up to about 10 atomic %, and then decreased toward that of Al{sub 3}V both at room temperature and at elevated temperatures. Such behavior can be interpreted as substitutional solid solution strengthening.

Two types of aluminum–titanium–iron–vanadium ( Al–Ti–Fe–V ) quarternary intermetallic compounds have been prepared by arc melting under argon atmosphere. Their compositions were nominally Al66Ti25Fe6V3 and Al66Ti25Fe3V6. These alloys are based on the iron–modified titanium trialuminide with L12 cubic structure. Vanadium addition up to about 6 mol% did not destroy the cubic symmetry, and L12 solid solution compounds were produced in these two Al–Ti–Fe–V quarternary alloys. Microstructure and mechanical properties have been investigated. It has been demonstrated that vanadium addition to iron–modified L12 titanium trialuminides can enhance their strength.

Two types of aluminum-titanium-vanadium ternary intermetallic compounds have been prepared by arc melting under argon atmosphere. Their compositions were nominally Al65Ti25V10 and Al57Ti22V21; the numbers represent the molar fractions in mol%. These two alloys stand within the gamma-phase field where the L10 face-centered tetragonal structure is produced. Metallographic structure and mechanical properties have been investigated. It is suggested that vanadium addition to titanium aluminides and titanium trialuminides can enhance their strength.

Tensile creep properties have been studied in Ti-50mol%Al intermetallics prepared by ingot metallurgy. Four types of structure were obtained in as-cast material (C), homogenized material (CA), isothermally forged material (F) and forged-and-recrystallized material (FA). Structural effects was investigated by comparing creep properties such as minimum creep rates, fracture strains and creep life among C, CA, F, and FA materials. Creep characteristics were strongly dependent upon the structure.

Surgical specimens from fifteen patients with intraductal papilloma were reconstructed three-dimensionally from semi-serial sections to visualize the intraductal distribution of papillomas. Our results showed two basically different papillomas. In five patients, the papillomas were single and originated in the large ducts such as the segmental or subsegmental duct, but did not involve the terminal ductal-lobular units (TDLU); this type corresponded to the so-called solitary papilloma. In the remaining ten specimens, the papillomas were multifocal three-dimensionally; each had a root in the TDLU and spread into the large ducts, suggesting its purely peripheral origin. In view of this striking difference, and of possible canceration of ductal peripheries, a nomenclature of peripheral vs central papillomas is proposed instead of the conventional multiple vs solitary. Duct papillomatosis, invariably situated within the TDLU, was shown to be a continuation of peripheral papilloma and was regarded accordingly as a prepapillomatous condition.

Cirrhotic livers of different types were subjected to three-dimensional graphic reconstruction of nodules, interstitial septa and blood vessels from serial histologic sections. It was found that in all cases adjacent cirrhotic nodules were connected to one another so as to form a nodular network, in spite of their apparent separation in histologic sections. The nodules were linked in the form of chains with abundant anastomoses, and the network was 'conjugate' with the intrahepatic vascular tree, as revealed by its close relationship to blood vessels. A parenchymal network of the same type was also found in livers with subacute or chronic hepatitis, suggesting that this type of structure was common to cirrhosis and its precursor lesions and represents the geometrical configuration of hepatic parenchyma surviving zonal hepatic necrosis. A Re-examination of chronic liver disease in terms of its structural framework provided a new viewpoint from which to analyse the morphogenetic problems of these disorders.

Constant stress compression creep behavior at elevated temperature was investigated on Ti-53.4mol%Al polycrystalline intermetallics of gamma single phase in different grain morphologies: coarse columnar grains, fine recrystallized grains and equiaxed grains. The shape of creep curves depended on the applied stress: normal primary transient followed by steady creep was found at higher stresses, but at lower stresses steep acceleration was observed after taking minimum creep rates. This behavior was common to all the grain morphology. The creep rate itself was not greatly different among the three types of structure, and the stress exponent of about 4 and the apparent activation energy of about 340kJ/mol at 0.3 true strain were common to all three types. The shape and size of grains do not affect the essential creep features of this material.