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RC橋脚の鉄筋に降伏強度が685N/mm2相当の高強度鉄筋を適用することにより，橋脚の断面積，軸方向鉄筋の本数を減少させることができる．橋脚躯体の物量低減は，直下の基礎の縮小にも繋がり，施工性の向上，建設コストの低減に有効である．RC橋脚への高強度鉄筋の適用については，設計基準強度が50N/mm2のコンクリートを使用した高さが60～120m程度の高橋脚において，高炉製高強度鉄筋が用いられた例がある．本研究では，これらの実績や既存の設計基準の適用範囲を上回る場合，および近年普及しつつある電炉製高強度鉄筋を使用した場合のRC橋脚の構造特性について，幾つかの構造実験による検証を行い，RC橋脚への高強度鉄筋の適用拡大に繋がる知見を取りまとめた．

Conventionally, two-dimensional velocity distribution of model experiment with relatively shallow water depth has been measured by surface tracers because intrusion of probe itself will disturb the flow field significantly especially, in the case of movable bed experiment. However, surface flow is not always a good representation of mean flow when secondary flow effects are not negligible. On the other hand, the dye-injection method has been used for understanding general flow features by visualizing the depthwise flow. In this paper, a novel idea of utilizing dye-injected flow images for the measurement of depth-averaged velocity distribution is proposed. Through the particle simulation and experiments using straight and curved channels, the validity of the new idea was verified.

River bed is composed of movable material such as sand or grain and small or large scale vortices are generated at the bed, which are generally lifted upward making confliction with water surface. The confliction of vortices against the water surface yields surface ripples making water-surface configuration rather complicated. Although there are a large number of researches on rough bed flows, the interrelationship between flow and water surface has not been clarified so far. In order to investigate fundamental features of flows with rough walls, measurements are made for the flows with strip roughness. A numerical simulation by LES is also performed to compare with the experimental results, showing a reasonable agreement with the experiments.

鋼管ソイルセメント杭は, セメントミルクを地盤中に注入攪拌することにより造成したソイルセメント柱に, 芯材として外面リブ付き鋼管およびリブの無い鋼管を使用した合成杭であり, 低騒音・低振動・低排土で施工できる杭工法である. 本工法を飛島高架橋西 (下部工) 建設工事において採用するにあたり, 設計法の改善およびコスト縮減を目的として, 2本の杭について現場載荷試験 (水平載荷試験後にさらに鉛直載荷試験を実施した杭と, 鉛直載荷試験のみを実施した杭) を実施した. 本論文では, 最初に, 水平載荷試験, 次に, 鉛直載荷試験について述べ, 支持力特性を検証した結果について述べる. さらに, これらの試験で得られた知見を設計法に反映した結果について述べる.

When a cachexigenic subclone (clone 20) of murine colon 26 adenocarcinoma was transplanted into female BALB/c mice, hepatic NNMT activity continued to increase until death in proportion to progressive carcass weight loss, a marker of cancer cachexia. On the other hand, noncachexigenic subclone (clone 5)-transplanted mice showed neither increase of NNMT activity nor carcass weight loss. Among cytostatic fluorinated pyrimidines, 5'-dFUrd could inhibit the increase of NNMT activity and prevent weight loss in mice bearing clone 20. On the other hand, 2'-dFUrd did not show these effects. 5-FUra and Tegafur inhibited the increase of NNMT activity at higher concentrations. These findings suggest that the levels of hepatic NNMT activity are closely associated with the degree of weight loss, and they appear to be a useful marker of cancer cachexia.

This study showed that nitric oxide (NO)-generating S-nitrosothiols, S-nitroso-N-acetylpenicillamine (SNAP) and S-nitrosoglutathione (GSNO), increased proliferation of BALB/c 3T3 (clone A31-1-1) fibroblasts in vitro. Treatment with SNAP at a relatively low concentration (0.005-0.02 mM) induced an increase in cell number compared to control. SNAP (0.005-0.02 mM) and GSNO (0.025-0.05 mM) both showed an increase of [3H]thymidine incorporation in exponentially growing cells in a dose-dependent manner. The maximal effect was observed at about 40 and 90% above control at 0.02 mM and 0.05 mM, respectively. The increase induced by 0.02 mM SNAP was abolished by the addition of 0.01 mM oxyhemoglobin, a scavenger of NO. [3H]Thymidine incorporation in stationary cells was also increased by SNAP. In addition, 0.02 mM SNAP produced a 1.8-3.2-fold increase of thymidine kinase activity in exponentially growing cells.

壁基礎は, フーチングの無い長方形充実断面の一枚壁状基礎であり, 掘削残土量が削減でき, 近接施工にも有利となる. この壁基礎を第二東海自動車道の高架橋基礎工に採用するにあたり, 合理的な設計法の確立を目的として, 実物大規模の載荷試験 (鉛直載荷試験2体, 水平載荷試験4体) を実施した. 本報告は, まず鉛直載荷試験によって明らかになった壁基礎の先端支持力と周面摩擦力について述べる. つぎに水平載荷試験結果およびそれをシミュレーションすることによって, 壁基礎の水平方向の設計法に関して検討した結果について述べる.

We show that if a connected closed orientable manifold $M$ admits a codimension one locally free smooth action $\phi$ of a connected nilpotent Lie group such that any orbit of $\phi$ is non-compact, then $M$ is homeomorphic to a nilmanifold. And as an example of such an action, we study also a homogeneous action.

A protein factor which stimulated [3H]thymidine uptake into free hepatocytes prepared from normal mouse liver was detected in the ascitic fluid of gynecological cancer patients. The factor was subsequently further purified from the ascitic fluid of an endometrial cancer patient by DEAE-Sephacel, Sephadex G-150 and Phenyl-Sepharose CL-4B column chromatographies, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed a single protein band of 54,000 Da, designated tentatively as 54K ascitic protein (54K-AP). 54K-AP was similar to human alpha 1-antitrypsin (alpha 1-AT) in terms of SDS-PAGE and immunological behavior, but was slightly different in terms of amino acid sequence and isoelectric point. Although 54K-AP inhibited the activities of bovine trypsin and alpha-chymotrypsin as did human alpha 1-AT, 54K-AP inhibited the plasminogen activator released from human endometrial cancer Ishikawa cells more efficiently than alpha 1-AT. Because, in contrast to normal serum, the serum from the endometrial cancer patients stimulated [3H]thymidine uptake into hepatocytes, the possibility arises that 54K-AP could be produced by the cancer host as a defence mechanism against the cancer.

Nicotinamide methyltransferase (Nmd CH3transferase) activity increased in the liver of mice after i.p. transplantation of Ehrlich ascites tumor (ascitic form), but not in the liver of mice with acute inflammation induced by the i.p. administration of D-galactosamine, and it rather showed a decrease together with necrosis after carbon tetrachloride administration. When Nmd CH3transferase activity of rat hepatocytes in primary culture was investigated with the addition of dexamethasone, epidermal growth factor, transforming growth factor-beta, tumor necrosis factor-alpha and N1-methylnicotinamide (1-CH3Nmd), changes in activity were not correlated with DNA synthesis, suggesting that the increase of this enzyme activity in the tumor host liver was not directly related to liver cell proliferation. Thus, in order to make use of the increase of this enzyme activity as a tumor burden marker, a procedure for its estimation by measuring the blood level of 1-CH3Nmd, a metabolite of Nmd produced by Nmd CH3transferase, was established. The 1-CH3Nmd level in the blood of mice bearing Ehrlich ascites tumor 4 h after s.c. loading of Nmd (500 mg/kg body weight) was closely correlated with this enzyme activity in the liver (r = 0.835, P less than 0.00001) from the early to the terminal stage of tumor development. Furthermore, similar correlations were seen in the animal groups bearing various other tumors, such as s.c. implanted Ehrlich ascites tumor (solid form) and i.p. implanted sarcoma S-180, hepatoma MH-134, Yoshida ascites sarcoma and leukemia L-1210, but not solid tumors such as Lewis lung carcinoma and melanoma B-16, although almost all of the animals bearing these tumors showed a higher enzyme activity than their control normal animals.

Anabolism of 5-fluorouracil (5-FU) in the presence of uracil was examined using the cell-free extract of Ehrlich ascites tumor cells. FU-nucleoside formation from 5-FU with ribose 1-phosphate (R-1-P) or 2'-deoxyribose 1-phosphate was not readily inhibited even by the addition of uracil at 100 times higher concentration than 5-FU. FU-nucleotide formation from 5-FU with R-1-P and adenosine 5'-triphosphate or with 5-phosphoribosyl 1-pyrophosphate was slightly reduced as the concentration of uracil was increased. It was also found that 5-fluorouridine (5-FUR) was produced by "nucleoside N-ribosyltransferase," transferring a ribose moiety from uridine (UR) to 5-FU directly. This activity might play a role in the preferential formation of 5-FUR. However, 5-fluoro-2'-deoxyuridine was not produced by directly transferring a deoxyribose moiety. On the basis of several column chromatographies and characterization of kinetics, pH dependency, and response to inhibitors, the enzyme protein of the ribosyltransferase could not be distinguished from that of the phosphorylase.

The cDNA clone encoding human thymidine kinase (hTK), was expressed in E. coli using a prokaryotic expression vector, pKK 223-3. The kinetics of the recombinant hTK (rhTK) were similar to those of cytosolic TK but not of mitochondrial TK. rhTK was highly purified in the presence of either ATP or dithiothreitol (DTT). The specific activity of rhTK purified in the presence of ATP [rhTK(ATP)] was lower than that of rhTK purified in the presence of DTT [rhTK(DTT)]. Activity of the purified rhTK(ATP) was enhanced by addition of thiols including DTT, cysteine, homocysteine and beta-mercaptoethanol but inhibited by various sulfhydryl reagents such as 5,5'-dithio-bis(2-nitrobenzoic acid). Hence, it was suggested that rhTK is a thiol-type enzyme. Apparent Mr of purified rhTK(ATP) was 100 kDa, which corresponds to the size of a tetramer (25 kDa subunit), while that of purified rhTK(DTT) was 50 kDa, the size of a dimer. The tetramer form of rhTK(ATP) was converted to the dimer by replacement of ATP by DTT. On the other hand, the dimer form of rhTK(DTT) was converted to the tetramer by addition of ATP. Thus, the catalytic activity of human cytosolic TK might be regulated by thiols as well as ATP via its polymerization status.

In the relatively small model experiment of river flow, the order of water depth becomes several centimeters and the measurement of mean velocity distribution using probe type instruments becomes difficult. In this research, in order to measure the depth-averaged velocity directly from image analysis, dye injection method is used. As a first step, particle simulation assuming particles moving with different speeds at multiple planes is performed. The PIV result indicates that the obtained velocity almost coincides with the mean velocity.

Summary Cytosolic thymidine kinase was purified 18,000-fold of the homogenate from murine Ehrlich ascites tumor, using the [p-aminophenyl 3'-dTMP]-CH-Sepharose affinity column. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified enzyme showed a single protein band of molecular weight 26,000. Two different forms, relative molecular weight 50,000 and 70,000, were found by gel f'dtration, depending on the existence of dithiothreitol, ATP and other nucleotides. These agents also stabilize and stimulate the enzyme activity. The existence of two forms was.also manifested by DEAE-Sephacel column chromatography, where the 50,000 form was eluted by 50 mM NaC1 and the 70,000 form by 400 mM NaC1.

In order to develop new ways of tumor diagnosis and therapy, it is important to know the metabolic changes occurring while bearing the tumor, since these ways should be applied to the cancer patient, who is, after all, a tumor bearer. Various metabolic changes in the tumor host tissues, especially in the liver, have been observed to take place together with tumor-growth (Fujimura and Shimizu, 1977; Shimizu and Fujimura, 1978; 1984; Asanagi et al., 1988; Tanaka et al., 1991; Nakagawa et al., 1991; Fujimura et al., 1992a; 1992b; Hanazawa et al., 1994; Fujimura et al., 1995).

CDP reductase was separated from the cytosol of rat Yoshida ascites sarcoma. The precipitate, which resulted from the acidification of the cytosol by acetic acid at pH 5.2, catalyzed specifically the reduction of CDP, whereas the concurrently resulted supernatant catalyzed those of UDP, ADP and GDP. The CDP reductase showed a single peak in the pattern of the enzyme activity in DEAE-cellulose and also in Sepharose 4B column chromatography with adequate recovery of the activity.

It was revealed that thymidylate kinase was purified together with cytosolic thymidine kinase from human term placenta by p-aminophenyl thymidine-3'-phosphate-CH-Sepharose affinity column chromatography, which has been commonly used for purification of thymidine kinase. In addition, it was noted that mitochondrial thymidine kinase and nucleoside diphosphate kinase were concurrently eliminated. In the presence of ATP, cytosolic thymidine kinase and thymidylate kinase could be separated from each other by Ultrogel AcA 34 filtration, and their molecular weights were estimated to be 70,000 and 50,000, respectively. On SDS-polyacrylamide gel electrophoresis, thymidine kinase protein exhibited a band of 26,000, which was compatible with the molecular weight of the enzyme subunit calculated from its cDNA, while thymidylate kinase protein showed 24,000. Thymidylate kinase could utilize either ATP or dATP as an efficient phosphate donor, and showed substrate specificity for dTMP.

Nuclei isolated from Novikoff ascites hepatoma cells by the citric acid procedure were found to be a useful source of nuclear 4 to 7 s RNA, i.e., approximately 9 mg were obtained per 100 g wet weight of cells. The 4 to 7 s RNA was separated into four main peaks by chromatography on Sephadex G100 columns and 11 or more components by polyacrylamide gel electrophoresis. Two uridylic acid-rich RNA fractions (approximately 5 to 7 s), which are found only in nuclei, were purified by preparative polyacrylamide gel electrophoresis; one was obtained in an electrophoretically homogeneous state and had a base composition of 22% adenine, 26% uracil, 33% guanine and 19% cytosine. The labeling patterns with either [ 14 C]sodium formate or [ methyl - 14 C]methionine as a precursor were different for the uridylic acid-rich nuclear RNA than for the 4 s and 5 s RNA. Evidence is presented that the uridylic acid-rich RNA of peak II is not a degradation product of high molecular weight RNA.

From the recently identified group of low molecular weight nuclear RNA's, a 4.5 S RNA, referred to as 4.5 S RNAi, was isolated, purified, and partially characterized. The 4.5 S RNA was initially obtained from nuclear 4 to 7 S RNA of Novikoff hepatoma cells by electrophoresis on preparative polyacrylamide gels. Chromatography on diethylaminoethyl-Sephadex resulted in the separation of three 4.5 S RNA components. Of these, the 4.5 S RNAi had a purity of approximately 90% as shown by terminal analysis, i.e. the 3'-terminal nucleoside of 4.5 S RNAi is uridine (87%) and its 5'-terminal nucleoside 3',5'-diphosphate is pGp (90%). The Tm of the 4.5 S RNAi is 65° and its nucleotide composition determined by absorbance is 24.8% AMP, 25.6% UMP, 24.6% GMP, and 25.0% CMP. This RNA has been shown to be localized in the extranucleolar portion of the nucleus. The whole 4.5 S nuclear RNA contains at least one more fraction, referred to as 4.5 S RNAiii, which has a blocked 3' terminal. Its nucleotide composition determined by absorbance is 26.6% AMP, 25.8% UMP, 28.5% GMP, and 19.1% CMP. Like the 4.5 S RNAi, this RNA is also localized in the extranucleolar portion of the nucleus.

The activity of thymidylate synthetase in the liver of the ddY strain male mouse increased transitorily according to the increase in tumor cell number at maximum 7-9 days after ip transplantation of Ehrlich ascites tumor. The enzyme was able to be purified from the tumor host mouse liver or from the normal mouse liver in the same manner as from tumor cells using Affi-Gel blue and methotrexate-Sepharose 4B affinity column chromatography. The three enzyme preparations obtained were purified at 27,000-38,000-, and 8,000-fold, and yielded total activities of 11, 3, and 16% of these homogenates, respectively. These preparations were similar in molecular weight to the whole enzyme (67,000) and its subunit (34,000), optimum pH, and Km values either for deoxyuridine 5'-monophosphate or tetrahydrofolate in the presence of formaldehyde. Furthermore, the amount of 5-fluoro-2'-deoxyuridine 5'-monophosphate forming the ternary complex with the enzyme and tetrahydrofolate paralleled the enzyme activities in the cytosol fractions of the three tissues. The characteristics of the tumor host liver enzyme were similar to those of the proliferating tissues, the Ehrlich ascites tumor.

Uridine diphosphate (UDP) reductase was isolated in the supernatant fraction obtained after the acidification of the cytosol of Ehrlich ascites tumor cells, and was found insensitive to 10 mM hydroxyurea. However, cytidine diphosphate (CDP) reductase, being separated concurrently in the precipitate fraction, was readily inhibited. In the cytosol fraction of either Ehrlich ascites tumor, Yoshida ascites sarcoma or regenerating rat liver after partial hepatectomy, UDP reduction activity, in contrast to CDP reduction activity, is not sensitive to hydroxyurea.

Chromatography on DEAE-Sephadex columns is a useful method for large-scale purification of components of nuclear 4–7-S RNA inasmuch as 30 mg of RNA were satisfactorily fractionated by this method. Nuclear 4–7-S RNA was separated into several distinct peaks by elution with a 0.5–0.8 M NaCl gradient at pH 3.4, 5.1 or 7.6. Of the various components, 4-S, 5-S and U2 RNA were highly purified by chromatography at pH 7.6 as shown by analytical polyacrylamide gel electrophoresis. At pH 5.1 or 3.4, U1 RNA was isolated in a highly purified state in a yield of 7% of total 4–7-S RNA. The 4.5-S nuclear RNA which was obtained as an electrophoretically homogeneous fraction by disc gel electrophoresis was fractionated into at least two components by chromatography on DEAE-Sephadex columns. In addition, the 5-S nuclear RNA was separated into three components.