N-n-ヘキシル-マレイミド (I), N-シクロヘキシル-マレイミド (II), N-ベンジル-マレイミド (III) の単独重合, 共重合をアゾビスイソブチロニトリル (IV) を開始剤としてテトラヒドロフラン中, 60℃で行った. 単独重合の初速度 (R_p) はR_p=k [I] ^2.5 [IV]

0.80

, R_p=>k [II] ^2.8 [IV]

0.80

, R_p=>k [III] ^2.7 [IV] ^0.54となった. kは速度定数である. 全重合の活性化エネルギー (

E

), 頻度係数 (A) は

E

=

22

.8kcal/mol (I),

22

.2kcal/mol (II), 24.1kcal/mol (III), A=

9

.5×10¹¹ (I),

6

.

4

×10¹¹ (II),

6

.

6

×10¹² (III) となった. またN-置換マレイミドとメタクリル酸メチル (V) との共重合におけるモノマー反応性比r₁, r₂およびQ,

e

値を次のように決定した. I (M₁) -V (M₂) 系でr₁=0.17, r₂=2.02, Q₁=0.56,

e₁

=1.43, II (M₁) -V (M₂) 系でr₁=0.13, r₂=2.29, Q₁=0.50,

e₁

=1.50, III (M₁) -V (M₂) 系でr₁=0.14, r₂=1.54, Q₁=0.79,

e₁

=1.63となった.

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Corrosion and inhibition tests were conducted on Oil Country Tubular Goods (OCTGs) in HCl and HCl/HF stimulation acid solutions at 65°C.
Commercial inhibitors effectively inhibited L- and 13Cr steels. Cr duplex steel, however, was not inhibited satisfactorily, especially at low HCl/HF concentrations. The form of corrosion of Cr was selective attack. At low HCl/HF concentrations, corrosion product was formed on Cr surfaces and inhibitors were considered to be interfered by this corrosion product.
To inhibit Cr, and to mitigate selective attack, high dosage of inhibitor was required. Another way of corrosion control was attained by the increase in HCl concentration. The increase in HCl concentration made the corrosion reaction more active and reduced the tendency to form the corrosion product, and resulted in the activation of inhibitors for Cr in stimulation acid solutions.

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In the first part of the present work the interaction of glycophorin with dimyristoylphosphatidylcholine (DMPC) is studied by freeze fracture electron microscopy, densitometry, calorimetry, and 90° static light scattering. An exothermic lipid/protein interaction energy of W_P=190 kJ•mol^-1 was found by application of the well known Van Laar relation for the displacement of the freezing point and the Gibbs-Duhem relationship. Secondly, the effects of Ca²⁺ on the lipid/protein interaction were studied. Following Ca²⁺ addition a remarkable decoupling of the interaction of the glycophorin head group with the bilayer surface was revealed by densitometry and gold-labeling electron microscopy. It is estimated that about % of lipid once disturbed by the adsorption of glycophorin head groups is decoupled after addition of Ca²⁺. Thirdly, the selective interaction of glycophorin with binary lipid mixtures was studied, including the mixtures of DMPC with dimyristoylphosphatidylserine (DMPS) and dilauroylphosphatidylcholine (DLPC), and the mixture of dipalmitoylphosphatidylcholine (DPPC) with DLPC.

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Background: Exenatide (EXE), a prototypical GLP-1R agonist, is known as glucoregulator, antiobesogenic and antidyslipidemic in hyperlipidic and hyperglucidic diet-induced obesity in rats (DIO). Objective: To evaluate bone effects of DIO and DIO treatment with EXE (DIO-

). Methods: 72-75-day-old male rats had access only to (i) hyperlipidic food (5.2 kcal/g) and 30% sucrose solution for drinking (1.2 kcal/mL), or (ii) received normocaloric diet (3 kcal/g) and were allowed to feed and to drink water ad libitum. 122-125-day-old rats with 20% overweight were selected from i as obese and those with normal weight were selected from ii as control (C) animals. Thus, obese animals remained untreated (DIO) or were treated with 10 μg EXE/kg sc (DIO-) daily, for 20 days. Plasma levels of insulin (INS), leptin (LEP), osteocalcin (OCN), carboxy-terminal telopeptide of type 1 collagen (CTX-1) (ng/mL), as well as calcitonin (CT) and procollagen type 1 amino-terminal propeptide (P1NP) (pg/mL) were measured by ELISA. Bone mineral density of femur (BMDF) (g/cm³) was measured by X-rays. Results: DIO exhibited similar INS (12.±1.83, n=) and CT (2.±1.05, n=), higher LEP (0.33±0.04, n=5) and lower CTX-1 (0.48±0., n=3) than C. The treatment of DIO with EXE restored LEP (0.04±0.02, n=5), decreased CTX-1 (0.50±0., n=5) and increased CT (.87±0.72, n=5). The levels of OCN (1.58±0.41, n=5), P1NP (.64±16.89, n=5) and BMDF (1.±0.07, n=5) of C and those of DIO and DIO- were similar. Conclusions: Despite of increased LEP, decreased CTX-1 and normal OCN, P1NP and BMDF reflect a relative normal balance in bone turnover in DIO. Mechanical overloading due to high body mass is known as a factor that promotes this normal condition. Given that EXE decreases 14% body mass of DIO, the present study suggests that normalization of LEP and increased CT and decreased CTX-1 are concomitant beneficial effects of EXE that contribute for maintaining bone turnover under decreased mechanical load in DIO.

Supported by FAPESP, CNPq and CAPES

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A study has been conducted to develop the composite sheets made by superplastic rolling/joining technique of steel-superplastic alloys which could be used for the damping material at high temperature. The superplastic alloys used were Zn-%Al alloy, Al-%Cu-0.5%Zr alloy and Al-12.%Mg₂Si alloy and the composite sheets consisted of the three layers of steel and superplastic alloy (. g. steel-s. p. alloy-steel, s. p. alloy-steel-s. p. alloy). In case of Zn-%Al alloy, the volume percentage of the alloy was changed at five steps of 0, 25, 50, 75 and 100%. The specimens were rolled at or 5 passes at 200°C and the final reduction became %. The laminar and granular structures could be obtained by heat treatments after rolling. In case of the other alloys, the volume percentage of the alloys was 50%. The specimens were rolled at 300°C and the final reduction became %. The results obtained were as follows;
(1) The damping capacity of the steel-Zn-%Al alloy composite sheet could be obtained several times values of the steel in room temperature. The damping capacity increased with increasing temperature. Above the temperature of 200°C, the damping capacity exceeded 0.1.
(2) In the composite sheets of steel-Al superplastic alloys, good formability could be obtained by heat treatment.

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B/rに対するTweenの放射線防護作用は, その大部分が分子中のpolyoxyethylene基に由来するものであって, 表面活性作用にはほとんど関係していないと結論できる。防護作用の機作は既知の防護剤のうちではグリセリンに類似しているが, B_s-1を防護しないことから, Tweenの防護作用はB/r株に特異的であって, DNAの修復機構に関係している可能性が示唆される。MEAとは相加的に働くことなく, むしろ阻害作用を示す。これらの結果から, Tweenの放射線防護作用は, 既知の防護剤とは異なった機作によるものと結論される。

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Purpose: The purpose of this study was to determine if the optical properties of zirconia and glass–ceramic (

.max) were affected by low-temperature degradation (aging).

Methods: Experiment samples were fabricated with seven zirconia brands (n=10): Zenostar, Zirlux, Katana, Bruxzir, DD-BioZX², DD-cubeX², NexxZr; and

.max were used as a control. This resulted in a total of samples in the experiment. The L*, a* and b* were measured for each sample, and then the optical properties including translucency parameter (TP), contrast ratio (CR), and opalescence parameter (OP) were calculated. The samples were aged (20, 40, 60, , 100h), and the optical properties were calculated after each interval.

Results: Most zirconia brands had lower L*, higher a*, higher b* with increased aging, which visually corresponds to darker, redder, and more yellow. Aging also increased CR, lowered TP, and lowered OP.

.max was also affected by aging but still had the highest TP (23.±2.8), L* (81.7±3.), and lowest CR (0.41±0.05) compared to any zirconia. The Zenostar had the closest TP (24.1±0.), and L* (90.2±0.5) values to .max before aging. However, after 100h of aging, the DD-cubeX² was least effected and had the highest TP (.2±0.) and lowest CR (0.43±0.01) compared with other zirconia samples and highest OP (11.3±0.2) of all ceramic samples.

Conclusions: The optical properties of zirconia and

.max materials were affected by aging with the effects increasing with time. The magnitude of change was affected by seven brands of dental zirconia.

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Chemical properties of ergosta-, , 8(14), -tetraen-3-one (1) were investigated. Though 1 is rather stable to acids or bases, it reacts easily with two moleculres of oxygen on irradiation with UV light to give , -epidioxy-14α-hydroperoxyergosta-, 7, -trien-3-one (2), which is transformed successively to , 7α;8α, -diepoxy-14α-hydroperoxyergosta-, -dien-3-one (3) and 14α-hydroperoxy--hydroxyergosta-, 7, -triene-3, -dione () under these reaction conditions.

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The purpose of this study was to examine the effect of extreme changes in step length on the oxygen uptake at fixed speeds, i.., 60, , 100 and 120m/min walking, respectively. The subjects were eight healthy active female students who performed treadmill walking for 18 min with the three different step lengths, i.., freely chosen (FCSL), as short as possible (SSL) and as long as possible (LSL) at each speed. During each walking trial, the step lengths changed every min. Determinations of oxygen uptake and step frequency were made during 5-, 11-12 and 17-18 min. The mean % VO₂max and oxygen uptake per 100meter (ml/kg/100m) were .-54.3 and 18.5-.1 for FCSL, 40.5-61. and 33.3-24. for SSL and 48.8-67.8 and 39.-27.5 for LSL at all speeds, respectively. The oxygen uptake per 100meter during walkings with the SSL and the LSL were significantly greater (p<0.05) than the FCSL at each speed. However, there were no significantly differences between walking with the SSL and the LSL. The mean increases in oxygen uptake per 100meter were 14.8-2.8ml/kg/100m for SSL and 20.-/kg/100m for LSL. Both extreme increase and decrease in step length from the freely chosen step length caused increase in oxygen uptake. These resuits indicate that extreme changes in step length affected walking efficiency.

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Endothelin (ET) receptor antagonists: BQ-123 (ET_A), BQ-788 (ET_B), tezosentan (dual ET receptor antagonist) protect against the development of postoperative ileus (POI) evoked by ischemia-reperfusion (I/R). The current experiments explored whether ET antagonists prevent the occurrence of POI evoked by surgical gut manipulation. Intestinal transit was assessed by measuring the rate of dye migration subsequent to skin incision (SI), laparotomy (L), or laparotomy and surgical gut handling (L+M) in diethyl ether anaesthesized rats (

). Experimental animals were randomly sub-divided into two groups depending on the time of recovery following surgery: viz. either 2 or 24 h (early or late phase POI). and SI did not affect the gastrointestinal (GI) transit. In contrast, L and L+M significantly reduced GI motility in comparison to untreated group (UN). Tezosentan (10 mg/kg), BQ-123 and BQ-788 (1 mg/kg) protected against development of L+M evoked inhibition of intestinal motility in the course of late phase, but not early phase POI. Furthermore, tezosentan alleviated the decrease in the contractile response of the longitudinal jejunal smooth muscle strips to carbachol in vitro induced by L+M. The serum ET(1–21) concentration was not increased in either the early or the late phase POI groups after surgery compared to control animals. This study indicates that delay in the intestinal transit in late phase of surgically induced POI involves an ET-dependent mechanism.

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The purpose of this study is to estimate radiation dose and image quality of ECG-gated coronary 320-area detector CT (ADCT) angiography which was acquired using the protocols that were considered as optimal methods for different heart rates (HR) in 1031 consecutive patients (M/F=580/451, 65±12 yr) without arrhythmias. We set up 5 protocols for 320-ADCT based on the relationship among heart rates, temporal resolution, gantry rotation speed, optimal reconstruction phase and slow filling phase on 64-multidetector-row computed tomography (MDCT), ie, 1) mid-diastolic (75% of RR) 1 beat scan (MD 1 beat, N=761(73.8%)) for HR≤60, 2) mid-diastolic (75% of RR) 2 beat scan (MD 2 beat, N=135) for 61≤HR≤65, 3) end-systolic and mid-diastolic (37–% of RR) 2 beat scan (ES-MD 2 beat, N=) for 66≤HR≤75, ) end-systolic (R+280–430 ms) 2 beat scan (ES 2 beat, N=21) for 76≤HR≤, and 5) end-systolic (R+250–400 ms) 3 beat scan (ES 3 beat, N=) for 81≤HR≤105. Image quality was classified into 3 categories (excellent (3 points), acceptable (2 points), and unacceptable (1 point)). Scanning time, DLP. and image quality score were 1.±0.1 s, 220±59 mGy·cm, 3.0±0.2 points in MD 1 beat, 2.2±0.2 s, 434±118 mGy·cm, 2.±0.3 points in MD 2 beat, 2.1±0.2 s, 729±229 mGy·cm, 2.7±0.5 points in ES-MD 2 beat, 1.±0.1 s, 432±148 mGy·cm, 2.2±0. points in ES 2 beat, and 2.±0.2 s, 669±152 mGy·cm, 2.3±0. points in ES 3 beat respectively. In conclusion, the prospective ECG-gated scan protocol for coronary 320-ADCT angiography in any HR group was considered reasonable and proper for image quality and radiation dose.

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Patterns of symptoms in the auditory system were clinically investigated among 26patients with ‘CATCH ’ syndrome treated in th Department of Otolaryngology of Tokyo Women's Medical College between March 1994 and September 1995. Chromosome analysis performed by means of the FISH technique at the Department of Pediatric Cardiology, showed a deletion within chromosome qll in all cases. Typical facial appearance of CATCH, such as ocular hypertelorism, lateraldisplacement of the inner canthi, narrow eye fissures, puffy eye lids, flat nasal bridge and small mouth was found in all cases. Auricular anomaly was shown most consistently. It was present in 20 cases, or 76.% of the patients. Half of the 20 cases with auricular anomaly showed lop ear, with their helix folded forward and drooping like rabbit ears. There were 7 satyr ears in cases, 2 macacus ears in l case and 7 other anomalous ears in cases. The frequency of otitis media including acute otitis media and otitis media with effusion was approximately%, but in most cases the degree was not severe. Conductive hearing loss was observed in 10 cases (38.5%), 5 were bilateral and 5 were unilateral. The severitywas mostly mild. There were neither sensorineural hearing loss nor mixed hearingloss. CT findings of the temporal bone were characterized by dilatation of eustachian tube (15.8%), aplasia or hypoplasia of the lateral semicircular canal (36.8%) and enlargement of the vestibule (36.8%). Caloric nystagmus test on ENG was done in 5 cases. There was no response to caloric stimulation in cases including 2 cases had severe and 2 had moderatecanal paresis. Auditory dysplasia inCATCH syndrome was found in the external, middle or innerears. Auricular anomaly was present in %, dilatation of eustachian tube in 15% and the vestibular dysplasia in 35%. There was one familial transmission in a mother and her son. The rest of thecases was sporadic.

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The antiallergic properties of a hop water extract (HWE) were studied by evaluating the Evans blue leakage from ICR mice caused by compound 48/ stimulation, and the histamine release from ovalbumin (OVA)-sensitized BALB/c mice. An oral administration of HWE significantly inhibited the vascular permeability and histamine release. HWE itself did not have any influence on the total and antigen-specific immunoglobulin (IgE) production in OVA-sensitized mice. These results indicate that HWE exerted an antiallergic effect by inhibiting the release of chemical mediators from mast cells and basophiles.

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The equivalent conductance of higher tetraalkylammonium perchlorates was measured in hexamethylphosphoric triamide (FIMPA); the values obtained for , ⁺ tetraheptylammonium ion (n-+), tetradecylammonium ion (n-+), tetradodecylammonium ion (n-+), trioctylpropylammonium ion (TOPN⁺), trimethyldodecylammonium ion (TMDN⁺), tetradecyldimethylbenzylammonium ion TDDBN⁺ and hexamethylenepiperidinium ion (+) were 21.2₀, , 21.0₅, , , 20.7₅, 18.0₀, and cm²Ω^-11mol^-1, respectively.
These values together with the data for +, +, n-+, n-+ and n-Hex, N⁺ in HMPA solution' indicate that + is the smallest in the effective radius calculated from the Stokes' law and TMDN⁺ is the largest in the tetraalkylammonium ions examined. The value for n-Dod, N⁺ is much the same with the value for +. The value for 5 N + is between the value for + and that for n-+. The solvation number obtained from the effective radius is 1-2 for +

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