Abstract: In a static induction type thyristor comprising a low impurity concentration channel region having opposed first and second major surfaces, a first main electrode region having one conductivity type and a second main electrode region having another conductivity type opposite to the one conductivity type and provided on the first and second major surfaces, respectively, and a gate region provided in the vicinity of the first main electrode region, there intervenes, between the channel region and the second main electrode region, a thin layer region having the same conductivity type as that of first main electrode region. The provision of this thin layer reegion contributes to allowing a markedly low impurity concentration as well as a decreased thickness of the channel region for a given maximum forward blocking voltage, making it feasible to obtain a high maximum forward blocking voltage and a high switching speed.

Abstract: As new compounds are provided a class of derivatives of actinonin represented by the general formula ##STR1## where R is a hydrogen or a lower alkyl group, which can exhibit the enzyme-inhibitory activities to a limited range of peptidases and show a remarkable enzyme-specificity, and which are effective to treat a cycloheximide-induced experimental amnesia in mice and are expectable to be useful to treat an amnesia in a mammalian animal, including human.

Abstract: In a method of performing a solution growth of a ZnSe crystal using Se as a solvent and relying on the temperature difference technique, the growth is performed under the conditions that the vapor pressure of Zn which is lower than the vapor pressure of Se is applied, under controlled manner, to the solvent during the growth process, in which the value of the Zn vapor pressure is held constant at 7.2 atm. .+-.30%, whereby a ZnSe crystal having a good crystal perfection is obtained.

Abstract: An integrated light-triggered and light-quenched static induction thyristor and fabrication process thereof adapted in such a manner that an integrated SIPT operates in the normal mode in order to enhance current gain, tail current generated at the light-quenching time is reduced in order to enhance turn-off gain, and an buried-gate type of light-triggered static induction thyristor and a photo-darlington circuit composed of a first and second static induction phototransistors are integrated on a high-resistivity substrate in order to permit manufacturing said thyristor compact as a whole in facilitated processes.

Abstract: In performing a solution growth of a Group II-VI compound semiconductor crystal by relying on the temperature difference technique under controlled vapor pressure on a solution growth apparatus having a recrystallizing zone, a source crystal supply zone and a vapor pressure controlling zone enclosed in a growth quartz tube and placed under different temperatures for the respective zones, wherein a heat sink is provided at the bottom end portion of the recrystallizing zone to cause a thermal flow to pass therethrough to the outside of the whole apparatus to insure that a single crystal will grow from this bottom end portion of the zone. The quartz tube may be enclosed in a pressure-resistant tube to apply a pressure to the growth quartz tube externally thereof to avoid its destruction to enable the growth to be performed at a high temperature to obtain a high growth rate. Thus, a large size crystal having a good crystal perfection can be grown.

Abstract: A new compound, i.e., 14-chlorodaunomycin, and its method of preparation are provided. The new compound, useful as an antitumor agent and as an intermediate in the preparation of (2"R)-4'-O-tetrahydropyranyladriamycin, is obtained by reaction of daunomycin with an alkyl ortho-formate and a brominating agent to produce a 14-bromo-13-dialkylketaldaunomycin, hydrolysis of the latter compound, then adding an excess of a solid metal/chloride to produce an acid addition salt of 14-chlorodaunomycin and concurrently salting out the latter compound from the reaction solution, followed by recovering the 14-chlorodaunomycin acid addition salt.

Abstract: The present invention relates to a stable medical composition for injection containing (1) a Spergualin of the formula: ##STR1## [wherein R is ##STR2## (wherein R' is a lower alkyl group having 1 to 4 carbon atoms), ##STR3## or a salt thereof and (2) at least one stabilizer selected from the group consisting of mannitol, maltose, dextran, lactose, cyclodextrin, gelatin, chondroitin sulfate, and human serum albumin; when R is ##STR4## mannitol is excepted. A spergualin is useful as cancer control agents and immunomodulators.

Abstract: As new compound are now provided ten compounds, namely 1-N-{(2R,3R)-4-amino-3-fluoro-2-hydroxybutyryl}kanamycin A; 1-N-{(2R,3R)-4-amino-3-fluoro-2-hydroxybutyryl}-2',3'-dideoxykanamycin A; 1-N-{(2R,3R)-4-amino-3-fluoro-2-hydroxybutyryl}-2',3'-dideoxy-2'-fluorokan amycin A; 1-N-{(2R,3R)-4-amino-3-fluoro-2-hydroxybutyryl}-5-deoxy-5-fluorokanamycin A; 1-N-{(2R,3R)-4-amino-3-fluoro-2-hydroxybutyryl}-kanamycin B; 1-N-{(2R,3R)-4-amino-3-fluoro-2-hydroxybutyryl}-3'-deoxykanamycin B; 1-N-{(2R,3R)-4-amino-3-fluoro-2-hydroxybutyryl}-3',4'-dideoxykanamycin B; 1-N-{(2R,3R) -4-amino-3-fluoro-2-hydroxybutyryl}-5-deoxy-5-fluorokanamycin B; 1-N-{(2R,3R)-4-amino-3-fluoro-2-hydroxybutyryl}-5,3'-dideoxy-5-fluorokanam ycin B; and 1-N{(2R,3R)-4-amino-3-fluoro-2-hydroxybutyryl}-5,3',4'-trideoxy-5-fluoroka namycin B, which are all useful as antibacterial agent in the therapeutic treatment of bacterial infections.

Abstract: In a static induction type thyristor comprising a low impurity concentration channel region having opposed first and second major surfaces, a first main electrode region having one conductivity type and a second main electrode region having another conductivity type opposite to the one conductivity type and provided on the first and second major surfaces, respectively, and a gate region provided in the vicinity of the first main electrode region, there intervenes, between the channel region and the second main electrode region, a thin layer region having the same conductivity type as that of first main electrode region. The provision of this thin layer region contributes to allowing a markedly low impurity concentration as well as a decreased thickness of the channel region for a given maximum forward blocking voltage, making it feasible to obtain a high maximum forward blocking voltage and a high switching speed.

Abstract: An integrated light-triggered and light-quenched static induction thyristor and fabrication process thereof adapted in such a manner that an integrated SIPT operates in the normal mode in order to enhance current gain, tail current generated at the light-quenching time is reduced in order to enhance turn-off gain, and a buried-gate type of light-triggered static induction thyristor and a photo-darlington circuit composed of a first and second static induction phototransistors are integrated on a high-resistivity substrate in order to permit manufacturing said thyristor compact as a whole in facilitated processes.

Abstract: The present invention relates to an immunosuppressing method which comprises administering a spergualin-related compound represented by the following formula ##STR1## (wherein R.sub.1 is --(CH.sub.2).sub.4 --, --(CH.sub.2).sub.6 --, ##STR2## R.sub.2 is --(CH.sub.2).sub.2 -- or --CH.dbd.CH--; and R.sub.3 is ##STR3## or pharmacologically acceptable salts thereof in an effective amount to a warm-blood animal.

Abstract: New compound, 3',4'-dideoxy-3'-fluorokanamycin B is now provided, which is useful as antibacterial agent.3',4'-Dideoxy-3'-fluorokanamycin B is prepared by a process comprising halogenating an N,O-protected derivative of 3'-deoxy-3'-fluoro-4'-O-sulfonylkanamycin B with a metal halide, reducing the resulting 4'- halogenated 3'-deoxy-3'-fluorokanamycin B derivative to convert its 4'-halo group into a hydrogen atom, and thereby to produce an N,O-protected derivative of 3',4'-dideoxy-3'-fluorokanamycin B, and removing the remaining amino-protecting groups and the remaining hydroxyl-protecting groups from the reduction product by conventional deprotecting methods.

Abstract: DL- or L-Threo-3-(3,4-dihydroxyphenyl)-N-methyl-serine which may also be termed as DL- or L-threo-adrenalinecarboxylic acid are now provided, which are new compounds useful for therapeutic treatment of Parkinson's disease and mental depression disease.

Abstract: An insulated-gate static induction transistor is formed by establishing a potential barrier in a semiconductor region of one conductivity type between the source and the drain regions of the other conductivity type. The height of the potential barrier should be sensitive to the drain voltage as well as to the gate voltage. Therefore, the semiconductor region should have a low impurity concentration and short length. The potential barrier can be established by non-uniformalizing the field effect of the gate voltage in the semiconductor region and/or by the built-in potential between the source region and the semiconductor region.

Abstract: A plurality of static induction transistors capable of establishing a controllable potential barrier for charge carriers in the channel region between the source and the drain under the influence of the potentials of the gate and the drain connected in series and integrated in a semiconductor chip to constitute a charge transfer train. The drain of one static induction transistor and the source of the next adjacent static induction transistor are integrated in common into a charge storage region. An insulated electrode is provided on each charge storage region to control the potential thereof. The charge transfer train can be driven by 4-phase, 3-phase or 2-phase signals. The gate electrode and the drain electrode for each transistor may be integrated to form directional 2-phase charge transfer train. Image pick up device of very high operation speed can be materialized with the above charge transfer train.

Abstract: A static induction transistor (SIT) which is made to operate with a forward gate bias by maintaining the width of the channel region at an appropriate value. Such an improved SIT is used as the inverter transistor in a merged transistor logic (MTL) semiconductor IC (integrated circuit) to reduce the time delay-power product by an order or more. The collector region of a bipolar load transistor is continuous to or also serves as the gate region of the inverter SIT. A plurality of channel regions are formed penetrating through this collection/gate region. This SIT is simple in structure, which enables a marked increase in the integration density.

Abstract: Disclosed is a 3-(4'-aminobutylamino) propylaminobleomycin having low pulmonary toxicity, which expressed by the following general formula[BX]--NH--(CH.sub.2).sub.3 --A--(CH.sub.2).sub.4 --Bwherein [BX] represents a residue remaining after removing a hydroxyl group from the carboxyl group of bleomycinic acid, A represents a group of the formula ##STR1## in which R.sub.1 represents (i) a hydrogen atom, (ii) an alkyl group having 1 to 10 carbon atoms, or (iii) a methyl which may be substituted by at least one of a phenyl group and a cycloalkyl group having 5 to 13 carbon atoms, said substituents being each optionally further substituted more than one position by one or more substituents selected from the class consisting of a halogen atom, a lower alkyl group having 1 to 4 carbon atoms, a lower alkoxy group having 1 to 4 carbon atoms, and benzyloxy group; and R.sub.2 represents a lower alkyl group having 1 to 4 carbon atoms or a benzyl group, B represents a group of the formula ##STR2## in which R.sub.3 and R.

Abstract: A tunnel injection controlling type semiconductor device comprising a source semiconductor region having a certain conductivity type for supplying carriers, a drain semiconductor region for receiving the carriers, and a gate electrode for controlling the flow of these carriers. A highly-doped semiconductor region having a conductivity type opposite to that of the source semiconductor region is provided in contact with the source region or contained locally in the source region to cause tunnel injection of carriers. The potential level of this highly-doped region is varied by virtue of the static induction effect exerted by the voltage applied to the gate electrode which is provided at a site close to but separate from the highly-doped region, and to the drain semiconductor region.

Abstract: As new 2'-deamino-2'-hydroxyistamycin B.sub.o derivatives are provided four compounds, namely 2'-deamino-2'-hydroxyistamycin B; 2'-deamino-2'-hydroxy-3-O-demethylistamycin B; 4-N-(.beta.-alanyl)-2'-deamino-2'-hydroxyistamycin B.sub.o ; and 4-N-(.beta.-alanyl)-2'-deamino-2'-hydroxy-3-O-demethylistamycin B.sub.o which all exhibit high antibacterial activity and low acute toxicity in combination. These new compounds are useful as antibacterial agent.

Abstract: A stable, non-hygroscopic, crystalline .gamma.-form of bestatin is prepared from the .alpha.- or .beta.-form of bestatin by heating at a temperature of from about 148.degree. C. to the melting point of bestatin, or by suspending or kneading in certan specified solvents.