アフィディコリン(APC)の修復合成阻害効果について不定期DNA合成(UDS)を指標に検討した。ヒト末梢血リンパ球を, DNA損傷誘発剤のマイトマイシンC (MMC),塩酸ニムスチン(ACNU),メチルメタンスルホン酸(MMS),および4-ニトロキノリン1-オキシド(4NQO)で前処理し,培養液で洗浄後, APCを添加したフィトヘマグルチニン(PHA)とトリチウムチミジンを含む培養液で15時間培養し, UDSを測定した。その結果,上記4種のDNA損傷誘発剤で処理したヒト末梢血リンパ球のG_1期でのUDSは, APCによって阻害されることが明らかとなった。

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With the object of surface-hardning, boronizing of iron with a mixture of H₂ and BCl₃ gas was studied. The results were as follows:
Microscopic examination of the microsection taken from the cross-section of the specimen showed that the boride film consisting of two layers was formed above 600°C. The microhardness of the boride layer was about 2000∼2200 on the surface, 1600∼1900 in the outer layer and 1300∼1500 in the inner layer. And each layer had a little gradient in microhardness. The results of X-ray analysis showed that the outer layer was FeB and the inner layer was Fe₂B, and that in each layer the C-axis of crystals grew up in a direction perpendicular to the surface.

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In this paper we study geodesics on curvature-adapted real hypersurfaces in non-flat quaternionic space forms. By observing the extrinsic shape of geodesics on these hypersurfaces we characterize them in the class of real hypersurfaces. We also investigate the length spectrum of geodesic spheres, which are the simplest curvature-adapted real hypersurfaces, in non-flat quaternionic space forms.

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　本研究では，日本人と中国人学生に対して色彩心理的傾向に関する調査が行われた．45色が選択枝として示され，43個の質問が行われた．グループ間の比較のために，ヒストグラムインターセクション法が用いられた．中国男女間 (C-FM)，日本男女間 (J-FM)，女性日中間 (F-JC)，男性日中間 (M-JC)の四つグループ間の値が得られた．それらの値によって，色彩心理的傾向の性別差異と国別差異を分析することができた．43個の質問に対するそれらの値に基づいて，グループ間の差異が検討された．平均値の差の検定や相関分析により四つグループ間の差異の順番はC-FM << J-FM < F-JC < M-JCであることが分かった．

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琵琶湖産ユスリカの主要種はアカムシユスリカとオオユスリカである.琵琶湖の南岸, 守山市にて無作為的に選択した各年齢層の気管支喘息患者にユスリカ抽出液による皮膚反応, RASTをおこない, その結果を他の地方における報告と比較し琵琶湖の影響を検討した.セスジユスリカ成虫抽出液によるスクラッチテストでは129名中35名(27%)に陽性で, 陽性患者はすべて室内塵にも陽性であった.アカムシユスリカによるRASTでは64名中16名(25%), セスジユスリカでは12名(19%)が陽性であった.セスジユスリカによる皮膚テストでは20〜39歳の層でもっとも陽性率が高かった.アカムシユスリカに対するRASTの陽性率は東京都, 富山市, 岡山市での成績に比し有意の差はなく, 琵琶湖の影響が特に大きいという結論は得られなかった.

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Degradation of L-ascorbic acid proceeds from dehydroascorbic acid, which is in turn hydrolyzed irreversibly by liver supernatant fraction to form 2,3-diketo-L-gulonic acid. This heat labile degradative factor was purified about 10-fold. The preparation had no esterase activity, but the activity was accompanied by lactonase I activity, The low activity of this dehydroascorbic acid hydrolysing enzyme in primates is correlated with the slow rate of ascorbic acid metabolism in these species. 2,3-Diketo-L-gulonic acid is further degraded nonenzymatically under aerobic condition to L-threonic acid, oxalic acid and carbon dioxide. Enzymatically, however, this compound is decarboxylated by 2,3-diketoaldonic acid decarboxylase forming isomeric products, L-lyxonic acid and L-xylonic acid. This enzyme was purified about 50-fold from rat liver supernatant. The products were identified as a form of benzimidazole crystals. Further metabolism of these three L-aldonic acids produced from ascorbic acid was also examined. The significance of ascorbic acid degradation was discussed.

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短期間の暑熱順化による発汗機能の変化機序について, 発汗中枢活動の指標である汗の拍出頻度（Fsw）を用いて検討した. 健康な男子大学生8名が6日間の暑熱下（環境温36℃）運動プログラムを行った. 運動プログラムの前後の日に, 温水循環スーツを用いた暑熱負荷テストを行い, 胸部と前腕部の局所発汗量（SR）, Fsw, 食道温（Tes）を測定した. 暑熱負荷中に発汗が開始するTes閾値は, いずれの部位でも暑熱順化によって有意に低下した（P < 0.01）. Fswは加温によって増加し, その増加は順化前後で有意に異ならなかった（P = 0.69）. Tesに対するSRあるいはFswの関係は, いずれも暑熱順化によってその勾配は変化しなかったが, より低いTesへ位置が移動した. FswとSRの関係は, いずれの部位においても暑熱順化によって有意に変化しなかった. 以上のことから, 暑熱暴露中に発汗中枢の活動が始まる深部体温閾値は, 短期暑熱順化によって低下すると推測された. 本研究の条件では, 発汗の末梢機構に有意な変化は認められなかった.

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This is the second paper of a series of studies on the tooth structure in various Arcacean bivalves, reporting microscopic observations of thin sections of the teeth area in the genus Arca. The tooth structure of genus Arca is different from those of many other shell structural patterns which have ever been studied by some investigators. In the genus Arca, the tooth is consisted of the aggregation of the second order lamellae, whose characteristic pattern is well demonstrated in a tangential thin section showing the simple and parallel aggregation of the fibrous microcrystals. The crossed lamellar structure is the major constituent of the outer shell layer in Arca and is also composed of the aggregation of the second order lamellae. However, from another point of view, the tooth structure and the crossed lamellae are clearly different from each other, especially in the aggregation pattern. That is, one of the latter is composed of the crossed aggregation of the second order lamellae, while the former is the simple aggregation of plate like lamellae of the second order lamellae. Therefore, the name of "simple lamellar structure" is newly proposed for the tooth structure of the genus Arca, whose idealised streographic model is shown in text-fig. 2. Another part of the tooth area, such as the hinge plate and the hinge socket are composed of crossed lamellar stucture and the irrgular crossed lamellar structure, respectively. These differences of the structures in the tooth area are due to the aggregation pattern of the second order lamellae. Therefore, the second order lamellae is considered to be the fundamental unit of these structures. From the preceding fact, it can be pointed out that the tooth structure of genus Arca having the simple lamellar structure, apparently differs from that of genus Anadara (MANO and OMORI, 1969), which has an elliptic lameller structure. Especially, the tangential section of the tooth area shows such difference as the former consisting of the simple aggregation of fibrous microcrystals in contrast to the latter having elliptic aggregation of the same. Morever, hinge plate of genus Arca is less faintly developed than that of Anadara. The type of the origination of the hinge tooth at the early stage of the tooth development, and the structure of the striation of the sides of the tooth are also reported.

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The diffusion coefficients of silver in the lead-tin system have been studied at the concentrations of tin N_Sn=0.223, 0.405, 0.614 and 0.799 and the temperature ranges of 410°∼557°, 453°∼609°, 391°∼609° and 405°∼690°C, respectively. The results can be represented by the equations:
(This article is not displayable. Please see full text pdf.)
\ oindentWith aid of thermodynamic properties of the Pb-Sn systems and supposing
(This article is not displayable. Please see full text pdf.)
\ oindentthe diffusion coefficients of tin in Pb-Sn systems at 500°C have been calculated by the equation
(This article is not displayable. Please see full text pdf.)
\ oindentThe calculated values of diffusion coefficients at various compositions agree well with those experimentally obtained in a previous study.

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A convenient calibration apparatus for a miniaturized hydrophone is described which is primarily intended for intracardiac, intravascular, intrauterine and various other uses in vivo. The present apparatus is composed of two parts to calibrate in a vibrating column of water shown in Fig. 2 and in a closed water-filled chamber shown in Fig. 8. As the first step of the calibration process, a monitor hydrophone (Fig. 5) to be used for a secondary standard is calibrated at low-audio frequencies by immersing the hydrophone in the vibrating column of water. When the water column is vibrated vertically and sinusoidally, the pressure in the water is proportional to the water height h and the acceleration as given by Eq. (4). The values of the correction factor for this apparatus due to wave effects are tabulated in Table 1. The sensitivity of a monitor hydrophone is -125. 4 dB re. 1 V/μbar at 100 Hz, and the frequency response is shown in Fig. 7. The secondary calibration of a miniaturized hydrophone is performed by comparing the unknown output with that of the monitor hydrophone in a closed water filled chamber shown in Fig. 8. Sinusoidal pressure is obtained by driving the diaphragm of the chamber by an electrodynamic vibrator excited by a beat frequency oscillator. Two factors for designing the closed chamber are represented by Eqs. (12) and (13) with a nondimensional parameter χ. The response frequency characteristics of a miniaturized hydrophone was measured by the apparatus mentioned above over the frequency range from 20 Hz to 5 kHz at a sound pressure level over 10^4 μbar. The results of the calibrations are shown in Fig. 13 and 14. Furthermore, the response to a static pressure fairly agreed with that to a sinusoidal pressure. The sensitivity has been measured with an accuracy of about ±1 dB.

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The enzyme obtained from a cell-free extract of baker's yeast is able to form thiamine diphosphate (TDP) from thiamine monophosphate (TMP) with ATP and Mg^<2+> as well as from thiamine. The enzyme which synthesize TDP from TMP was purified with heat treatment. ammonium sulfate fractionation and DEAE-cellulose column chromatography. The obtained enzyme was partially purified 18 fold in a specific activity of TDP formation from TMP, accompanying the thiaminokinase activity which was not able to separate and also containing a little TMPase activity. In order to exclude the participation of TMPase in TDP formation from TMP, a chemically synthesized TMP-^<32>P was used as a substrate and TDP-^<32>P formed enzymatically was isolated from the reaction mixture. The consistency of specific radio-activities of the TMP-^<32>P used and the formed TDP-^<32>P suggests the direct phosphorylation of TMP to form TDP, that is an exsistence of TMP-phosphokinase.

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Thiamin pyrophosphokinase purified to homogeneity from pig brain showed following properties. 1) The enzyme required Mg^<2+>, Co^<2+> or Zn^<2+> as a cofactor and ATP or UTP as a cosubstrate for its activity. 2) The pH optimum was between pH 6 and 7,and the Km values for thiamin and ATP were 0.43μM and 0.78 mM, respectively. 3) The reaction was inhibited by several nucleotides among which GTP, GDP, GMP and IMP showed remarkable inhibitions by competing with ATP, and Ki values for the nucleotides were 3.8,1.5,20 and 34μM, respectively. 4) Thiamin analogues such as pyrithiamin, 2-northiamin and chloroethylthiamin were competitive inhibitors for thiamin with Ki values of 0.85,5.8 and 27μM, respectively, whereas TMP, TDP and thiamin sulfate showed noncompetitive inhibitions with Ki values of 17,0.67 and 6.0μM, respectively. 5) Neuroactive amines such as serotonin and dopamine acted as weak inhibitors of the enzyme and the inhibitions appeared to be competitive with respect to thiamin. 6) The purified enzyme was reversiblly inactivated by SH reagents such as PCMB and NEM suggesting that it is an SH enzyme.

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