Showing papers by "Korea University published in 1982"

Therapeutic Trial of Praziquantel (Embay 8440; Biltricide ® ) on the dermal and cerebral human cysticercosis

Abstract: A total of 28 adult cases who were confirmed cysticercosis with or without cerebral involvements were treated with praziquantel at the daily dose of 3 x 25 mg/kg for 3 to 7 consecutive days and was evaluated for tolerance and therapeutic effects in the trials clinically performed.The assessment of drug efficacy of praziquantel in the dermal cysticercosis was made by comparing the numbers of cysticercus nodules and histopathological findings of the biopsied parasites by means of light, scanning and transmission electron microscope. In the cerebral cysticercosis, the assessment was considered by the frequency of the episodes of convulsive seizure before and after treatment with praziquantel and by the findings of the disapearance or decreased densities of the lesions in C.T. scan in comparison with those of before and after treatment. The results were as follows: 1. The cysticerci in the subcutaneous tissues began to disappear within one month of drug administration of 3 x 25 mg/kg praziquantel over 3 to 7 days. Within 3 to 6 months most of the cysticerci had disappeared, although in some case a small number of cysticercus nodules remained even one year after treatment. 2. Histological observation of the cysticerci biopsied at different times during the course of treatment revealed that morphological changes were already taking place within two weeks after the treatment. At the early stage of the treatment, small vacuoles were scattered along the basement layer in the tegumental syncytium of the scolex and neck regions. In the scanning electron microscopic observation, marked surface changes were present in the neck region with many bleb-like structures formed by the bursting of the large vacuoles in the tegumental syncytium. In the specimens biopsied at 2 or 5 weeks after treatment, the degenerations and necrosis of the tegumental syncytium were seen in all parts of cysticercus. 3. In 12 cases of cerebral cysticercosis treated with praziquantel at the daily dose of 3 x 35 mg/kg for 3 or 4 consecutive days, there were no ceasing of the convulsive seizures during the 6 months follow-up. Among them 9 cases were given again the same doses of the drug for 4 or 7 days. In 7 of 9 cases, no more convulsive seizure was experienced over one or two years after the second time. At the same treatment the lesions of the brain C.T. scan disappeared, decreasd in size or calcified after treatment. In other 3 cerebral cysticercosis cases, complete cure was also obtained after the oral medication of praziquantel at the daily dose of 3 x 25 mg/kg for 7 consecutive days. 4. In the treatment of cerebral cysticercosis with praziquantel, it was found that the concomitant oral medication of dexamethasone during the course of treatment was effective for preventing and minimizing the side-effects.

Electrical resistivity and crystallization of amorphous Cu-Ti alloys

Abstract: A systematic study of the electrical resistivity of amorphous Cu-Ti alloys was carried out in the temperature range 300–1000 K. The resistivity at room temperature varied from 290 to 350 μΩ cm. The temperature coefficient of resistivity was very small (of the order of 10−5 K−1). When a heating rate of about 2–3 K min−1 was applied the amorphous alloys transformed progressively into the crystalline phase at temperatures above 580 K. The crystallization kinetics of amorphous Cu-Ti alloys were determined from electrical resistance measurements performed during isothermal annealing. Atomic diffusion is proposed as the kinematic mechanism for these alloys.

Therapeutic field trial with praziquantel (Biltricide) in a rural population infected with Clonorchis sinensis.

Abstract: The present study was undertaken to determine the acceptablility, tolerance and effectiveness of praziquantel in a rural population infected with Clonorchis sinensis and to suggest the suitable dosages of praziquantel for the field use on a large scale. A total of 121 patients with proven C. sinensis infection were treated by two dosages with praziquantel at a single dose of 40 mg/kg bwt and 2 doses of 30 mg/kg bwt in a single day. A single dose of 40 mg/kg bwt were given to 60 patients and 2 x 30mg/kg bwt were given to 61 patients. Follow-up examinations were carried out at about 30 and 60 days after treatment. Two months after therapy, 13(21.7%) of 60 patients who received a single dose of 40 mg/kg bwt were cured completely. Among these cured patients, 9(75.0%) out of 12 cases of light and only 4 out of 48 cases of moderate or heavy infection groups were cured. But in the non-cured cases the overall egg reduction rate was 89.1%. On the other hand, 36(59.0%) out of 61 patients treated with 2 x 30 mg/kg bwt were cured at 60 days after treatment. Among these cured patients, all of the 13 cases of light infection and 18(69.2%) out of 26 cases of moderate and 5(23.8%) out of 21 cases of heavy infection groups were cured completely at 60 days after therapy. However the overall egg reduction rate was 95.2% in the non-cured cases. Praziquantel is well tolerated and side effects consist particularly of mild and transient headache, dizziness and abdominal discomfort, etc. However there was no difference in regard to frequency and intensity of untoward side effects between the two dosage groups. The results obtained in this study suggest that a single dose of 40 mg/kg bwt for light infection, 2 x 30 mg/kg bwt for moderate infection and 3 x 25 mg/kg bwt for heavy infection groups will be recommended for the field use on a large scale.

Fatigue crack initiation and propagation in a quenched and tempered niobium bearing HSLA steel

Abstract: The fatigue crack initiation and propagation behavior of a niobium bearing HSLA steel heat treated to give two tempered martensitic microstructures presumably with and without fine niobium carbides has been studied by light microscopy, electron microscopy, and strain gage measurements of plastic zone deformation. The high cycle, stress controlled fatigue life of the steel in both heat treated conditions was quite similar with the steel presumably containing the fine niobium carbides having slightly better resistance at low stress amplitudes. This slightly better high cycle resistance is associated with better resistance to fatigue crack initiation for this heat treatment. The fatigue crack propagation behavior of the steel was the opposite. The steel presumably containing the fine niobium carbides exhibited a much faster fatigue crack growth rate than that without them. The difference in growth rates is explained in terms of the plastic work expended during the propagation of the fatigue crack.

Epitaxial Integrated E-dE Position Sensitive Silicon Detectors

Abstract: The epitaxial integrated E-dE position sensitive silicon detector has been developed as an extension of the epitaxial integrated E-dE silicon detector. The charge dividing resistor is produced by evaporation of Pd on the E side of the detector. This Pd evaporated layer acts as the surface barrier electrode of the E detector. The good position sensing characteristics will be expected by using the charge dividing resistor made of a P-type epitaxial silicon layer grown on the substrate instead of the evaporated Pd layer.

Corrosion behavior of amorphous fe-cr-al-p-c ribbon alloys

Abstract: Corrosion resistance of amorphous Fe72Cr8-xAlxP13C7 ribbons produced by a rapid quenching method has been investigated in several solutions. The corrosion test for amorphous ribbons was carried out, and anodic polarization curves have been measured in the solutions. Resultantly, even in the amorphous Fe72Cr8-xAlxP13C7 ribbons containing a low Cr content, this composition of amorphous alloys showed the high corrosion resistance.

ATOMIC-SCALE STRUCTURE OF AMORPHOUS (Ni-Co)-(Zr-Hf) ALLOYS

Abstract: Determination des structures des alliages amorphes Ni 35 Zr 65 et (Ni-Co)-(Zr-Hf) en employant la methode de l'angle 2θ variable pour les rayons X et la technique de la longueur d'onde variable pour les neutrons. Les fonctions partielles d'interference (facteurs de structure partiels) ont ete evaluees par la methode de substitution isomorphe

High-Voltage Operation of Surface Barrier Silicon Detectors with a Side Groove

Abstract: A remarkable characteristic of the surface barrier detector with a side groove cooled down to the nitrogen temperature has been observed. That is an abrupt decrease of the output noise at a definite voltage in increasing the bias voltage slowly. This is caused by a carrier injection from the side surface of the groove near the neck narrowed by the side groove. This excess noise disappears after the depletion layer goes through the neck of the side groove. This is confirmed by the fact that the capacitance of the detector decreases abruptly with the decrease of the noise at the same bias voltage. This detector is capable to be operated at a voltage higher than this voltage with a low noise. The maximum bias voltage applied to the detector is 3000 V.

Sound attenuation in liquid 4He at very low temperatures

Abstract: The decay threshold, phonon width and spreading angle evaluated from the anomalous energy dispersion, obtained from a microscopic theory, are found to be in good agreement with experiment Relations with some other theories are also discussed

Immobilization of β-Galactosidase from E. Coli CSH36 and its Microbial Cells Using Cellulose Beads

Abstract: Using porous cellulose beads as a suitable matrix, Chen et al. (1) and Chun et al. (2) immobilized some enzymes by covalent or ionic binding, respectively; and Linko et al. (3) entrapped S. cerevisiae yeast cells within the beads. The retention of activity and the kinetic properties of β-galactosidase and E. coli mutant cells immobilized respectively on a) cellulose beads which were treated with p-benzoquinone and b) tannin by covalent binding and adsorption coupling were investigated in this work.