67 research outputs found
Algebraic structure of the Feynman propagator and a new correspondence for canonical transformations
We investigate the algebraic structure of the Feynman propagator with a
general time-dependent quadratic Hamiltonian system. Using the Lie-algebraic
technique we obtain a normal-ordered form of the time-evolution operator, and
then the propagator is easily derived by a simple ``Integration Within Ordered
Product" (IWOP) technique.It is found that this propagator contains a classical
generating function which demonstrates a new correspondence between classical
and quantum mechanics
Fluorescence in situ hybridization (FISH) analysis of primary ocular adnexal MALT lymphoma
BACKGROUND: It remains unknown whether primary ocular adnexal extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is a homogeneous entity, as there are few reports of the results of cytogenetic or molecular analyses of these tumors. METHODS: We performed interphase fluorescence in situ hybridization (FISH) analysis to detect translocations and aneuploidy in 34 cases of primary ocular adnexal MALT lymphoma, and reviewed the histopathological findings. Correlations between the results of FISH analysis, the histopathological features and the clinical data were also analyzed. RESULTS: Among the 34 cases, FISH analysis revealed t(14;18)(q32;q21) in one case, trisomy 3 in 21 cases (62%), and trisomy 18 in 16 cases (47%). The cases with trisomy 18 had significantly more prominent lymphoepithelial lesions (LELs) and less nodularity in the tumors. In regard to the clinical correlations, tumors with trisomy 18 were observed predominantly in females and younger patients; also, in the majority of the cases, the tumor was of conjunctival origin. All the cases with recurrence showed trisomy 18 in the tumor. CONCLUSION: Primary ocular adnexal MALT lymphoma is a significantly heterogeneous entity. Cases with trisomy 18 may have unique clinicopathological features
純チタンの鋳造性に関する研究(第4報)通気性の低い鋳型への鋳造
The purpose of this study was to evaluate the influence of casting molds with low permeability on the castability of pure titanium with an all directional pressured type casting machine. Two types of phosphate bonded casting molds were used, T-INVEST and T-INVEST C&B. We reported high performance of castability of pure titanium with an all directional pressured type casting machine, if the permeability of the investment was lower as possible. Specially prepared metal sealed rings to decrease gas permeability of casting mold were used. Two sizes of sprue condition were prepared, 1.26 and 1.48mm, under a casting pressure of 8kgf/cm^2. Five sizes of casting molds were prepared with mold diameters of 25, 35,45,55 and 65mm. The following results were obtained: A high percentage of castability was gained in T-INVEST using a high gas permeability casting mold with the sealed ring. A low percentage of castability was gained in T-INVEST C&B using a low gas permeability casting mold with the sealed ring. Back pressure action in the casting mold of T-INVEST C&B seemed to produce negative effects regarding the castability. These results indicated that the sealed ring was effective to promote pure titanium castability with a mold of high permeability
純チタンの鋳造性に関する研究(第3報)鋳造圧およびスプルー径がチタンの鋳込率に及ぼす影響について
We analyzed the external defects of castings with mesh grid patterns with 3 different kinds of phosphate bonded casting molds with 2 parameters (sprue diameter and casting pressure). Castability with pure titanium was affected by the parameters of sprue diameter, and casting pressure with different casting molds. The sprue condition was the most affective casting condition in the all directional pressure type casting machine. In 2 types of casting molds, one was strongly affected by the casting pressure in castability and the other was scarcely affected by the casting pressure. The former type of casting mold had a low permeability
Biochemical behavior of N-oxidized cytosine and adenine bases in DNA polymerase-mediated primer extension reactions
To clarify the biochemical behavior of 2′-deoxyribonucleoside 5′-triphosphates and oligodeoxyribonucleotides (ODNs) containing cytosine N-oxide (Co) and adenine N-oxide (Ao), we examined their base recognition ability in DNA duplex formation using melting temperature (Tm) experiments and their substrate specificity in DNA polymerase-mediated replication. As the result, it was found that the Tm values of modified DNA–DNA duplexes incorporating 2′-deoxyribonucleoside N-oxide derivatives significantly decreased compared with those of the unmodified duplexes. However, single insertion reactions by DNA polymerases of Klenow fragment (KF) (exo−) and Vent (exo−) suggested that Co and Ao selectively recognized G and T, respectively. Meanwhile, the kinetic study showed that the incorporation efficiencies of the modified bases were lower than those of natural bases. Ab initio calculations suggest that these modified bases can form the stable base pairs with the original complementary bases. These results indicate that the modified bases usually recognize the original bases as partners for base pairing, except for misrecognition of dATP by the action of KF (exo−) toward Ao on the template, and the primers could be extended on the template DNA. When they misrecognized wrong bases, the chain could not be elongated so that the modified base served as the chain terminator
Proteomic analysis identifies proteins that continue to grow hepatic stem-like cells without differentiation
To understand the molecular mechanism underlying vigorous proliferative activity of hepatic stem-like (HSL) cells, we performed two-dimensional electrophoresis to identify the proteins statistically more abundant in rapidly growing undifferentiated HSL cells than in sodium butyrate-treated differentiated HSL cells. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry and Mascot search identified 6 proteins including prohibitin, vimentin, ezrin, annexin A3, acidic ribosomal phosphoprotein P0 and Grp75. Prohibitin and vimentin control the mitogen-activated protein (MAP) kinase pathway. Ezrin is phosphorylated by various protein-tyrosine kinases and modulates interactions between cytoskeletal and membrane proteins. Annexin A3 has a role in DNA synthesis. Acidic ribosomal phosphoprotein P0 and Grp75 play in protein synthesis. These results suggest that the proteins related to the MAP kinase cascade had some role in continuous proliferation of HSL cells without differentiation
小学校教諭の器械運動指導に関する意識について ~群馬県A市小学校教諭に対する意識調査から~
小学校では、体育授業を学級担任が実施することが原則になっているが、近年では、高学年において専科制が導入されるなど徐々に小学校の実態に応じた取り組みが工夫され実践されるようになってきた。しかし、多くの場合、学級担任が授業を実施しているのが現状である。小学校教員の体育授業についての意識、特に、今回は器械運動についての意識をアンケート調査し、よりよい体育授業づくりに向けてどのように取り組んでいったらよいか、体育実技講習会の在り方について反映できることはないかを研究目的として実施する。器械運動に関しては、小学校教員の6割から7割近くの教員が不得意意識を持っている結果が見られた。特に鉄棒運動、跳び箱運動、マット運動の順番で苦手意識を持っているようである。講習会で研修したい内容としては、技能を身に付けさせるポイントについて、場の工夫の仕方について研修を深めたいと考えている。講習会の事後アンケートの感想でも技術習得のための支援に関するポイントが学べたなどの感想が見られた。教員の苦手意識を克服していくための内容を大切にし講習会を開催することが重要であると考えられる
Establishment of Functioning Human Corneal Endothelial Cell Line with High Growth Potential
Hexagonal-shaped human corneal endothelial cells (HCEC) form a monolayer by adhering tightly through their intercellular adhesion molecules. Located at the posterior corneal surface, they maintain corneal translucency by dehydrating the corneal stroma, mainly through the Na+- and K+-dependent ATPase (Na+/K+-ATPase). Because HCEC proliferative activity is low in vivo, once HCEC are damaged and their numbers decrease, the cornea begins to show opacity due to overhydration, resulting in loss of vision. HCEC cell cycle arrest occurs at the G1 phase and is partly regulated by cyclin-dependent kinase inhibitors (CKIs) in the Rb pathway (p16-CDK4/CyclinD1-pRb). In this study, we tried to activate proliferation of HCEC by inhibiting CKIs. Retroviral transduction was used to generate two new HCEC lines: transduced human corneal endothelial cell by human papillomavirus type E6/E7 (THCEC (E6/E7)) and transduced human corneal endothelial cell by Cdk4R24C/CyclinD1 (THCEH (Cyclin)). Reverse transcriptase polymerase chain reaction analysis of gene expression revealed little difference between THCEC (E6/E7), THCEH (Cyclin) and non-transduced HCEC, but cell cycle-related genes were up-regulated in THCEC (E6/E7) and THCEH (Cyclin). THCEH (Cyclin) expressed intercellular molecules including ZO-1 and N-cadherin and showed similar Na+/K+-ATPase pump function to HCEC, which was not demonstrated in THCEC (E6/E7). This study shows that HCEC cell cycle activation can be achieved by inhibiting CKIs even while maintaining critical pump function and morphology
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