Abstract: In a static induction type semiconductor device comprising a semiconductor region having one conductivity type and a low impurity concentration and gate regions having an opposite conductivity type and a high impurity concentration formed in the semiconductor region to thereby define a channel region between these gate regions, there is provided a subsidiary semiconductor region having the one conductivity type and a relatively high impurity concentration either around each gate region to leave an effective channel region in the semiconductor region, or adjacent to the effective channel region in the entire channel region on the drain side. By so constructing the device, this effective channel region has a relatively low potential difference even when the channel region is completely depleted, and provides a relatively wide current path.

Abstract: New derivatives of the istamycin B series of compounds are provided, which are 3-O-demethylistamycin B.sub.O, 3-O-demethylistamycin B and 3-O-demethyl-2"-N-formimidoylistamycin B represented generally by Formula I or specifically by Formulae Ia, Ib and Ic, respectively. Compound Ia is useful as an intermediate for the preparation of Compounds Ib and Ic and the latter two compounds exhibit a high antibacterial activity against a wide variety of Gram-positive and Gram-negative bacteria and are useful antibiotics. Also provided are processes for the preparation of the new derivatives starting from istamycin B.sub.O.

Abstract: The novel antibiotic, oxanosine, having the structure ##STR1## inhibits the growth of Gram-negative bacteria and has antiviral activity. It is produced by cultivation of an oxanosine-producing microorganism of the genus Streptomyces, preferably Streptomyces capreolus MG265-CF3, ATCC No. 31963.

Abstract: 5,2',3',4',4",6"-Hexadeoxykanamycin and 1-N-[(S)-4-amino-2-hydroxybutyryl]-5,2',3',4',4",6"-hexadeoxykanamycin are now provided, which are each a new compound useful as antibacterial agent. The hexadeoxykanamycin is semi-synthetically produced from 3',4'-dideoxykanamycin through consecutive steps which are ingeniously combined with each other to remove the 5-, 2'-, 4"- and 6"-hydroxyl groups. The 1-N-acylated hexadeoxykanamycin is produced by acylating the 1-amino group of hexadeoxykanamycin with (S)-4-amino-2-hydroxybutyric acid.

Abstract: A hetero-junction static induction transistor (SIT) of normal or upside-down type to be operated by applying a forward bias across the gate and source regions, in which at least its source region and gate region among the source, drain and gate regions is formed with a material having a band gap broader than that of the channel region. Such a SIT provides a large current amplification factor, improved frequency characteristics and is suitable for high power operation and for use in semiconductor integrated circuits.

Abstract: A thermionic emission transistor comprising: an emitter region formed with a semiconductor material having a first conductivity type and a high impurity concentration; a collector region formed with a semiconductor material having a first conductivity type and a high impurity concentration; a base region made of a semiconductor material having a second conductivity type opposite to said first conductivity type and a high impurity concentration, that portion of said emitter region located adjacent to said base region having an energy band gap broader than that of the base region, that portion of said base region located adjacent to the emitter region having an impurity concentration of about 3.times.10.sup.18 cm.sup.-3 or more. Such new transistor has a large transconductance and can be operated with a very large current gain in spite of a very small size of the whole device, and is very suitable for integrated circuit.

Abstract: As new compounds are provided 3-demethoxyistamycin B and 3-demethoxy-2"-N-formimidoylistamycin B which each is useful as antibacterial agent because of its high antibacterial activity against a wide variety of gram-positive and gram-negative bacteria including mycobacteria. These new compounds may be produced by removal of the 3-hydroxyl group of an N,O-protected 3-O-demethylistamycin B.sub.o, followed by glycylation of the liberated 4-methylamino group and, further, if necessary, followed by formimidoylation of the 2"-amino group of an intermediate N-protected 3-demethoxyistamycin B derivative.

Abstract: Tylosin compounds of the formula ##STR1## wherein R.sub.1 represents a hydroxyl group; a halogen atom; ##STR2## group (wherein R.sub.5 is a hydrogen atom or a lower alkyl group which may be substituted by a hydroxyl group and R.sub.6 is a hydrogen atom, a lower alkyl group which may be substituted by a hydroxyl group, an aryl group, an aralkyl group, a cycloalkyl group having 3-10 carbon atoms, --CO(O).sub.m --R.sub.7 group (wherein m is 0 or 1 and R.sub.7 is a lower alkyl group, an aryl group, an aralkyl group, a furanyl group, or a pyridyl group), or --CH.sub.2 --R.sub.13 group (wherein R.sub.13 is a mono-, di-, or trifluoromethyl group)); --N(CH.sub.2).sub.n group (wherein n is an integer of 2-15) which may be substituted by an oxo group, a hydroxyl group, a lower alkyl group, or a hydroxy lower alkyl group; an imidazolyl group, a morpholino group, or a piperazino group each may be substituted by a lower alkyl group; or --OOCCH.sub.2 --R.sub.8 group (wherein R.sub.8 is ##STR3## group (wherein R.sub.

Abstract: New 3-N-acyl derivatives of 3-amino-2-hydroxy-4-phenylbutanoic acid are provided, which exhibit analgesic activity and are affective to enhance the morphine analgesia.

Abstract: A new istamycin A derivative called di-N.sup.6', O.sup.3 -demethylistamycin A exhibits a high antibacterial activity against various bacteria, particularly Pseudomonas aeruginosa. This compound can be prepared by selective acylation of the methylamino group at the 4-position of 1,2',6'-tri-N-protected N.sup.4 -deglycyl-di-N.sup.6', O.sup.3 -demethylistamycin A with glycine or an N-protected derivative thereof, followed by N-deprotection.

Abstract: A new antibiotic BMG162-aF2 having the formula ##STR1## can be obtained by cultivating a BMG162-aF2-producing strain belonging to the genus Bacillus in a culture medium to produce and accumulate the said BMG162-aF2 and then recovering it from the culture medium. The antibiotic BMG162-aF2 thus obtained or a pharmaceutically acceptable salt thereof can be used for the treatment of a transplanted tumor in warmblooded animals.

Abstract: A new semi-synthetic antibiotic, 3"-deoxystreptomycin is now provided, which is useful as an antibacterial agent and is produced from 3"-deoxydihydrostreptomycin by a process comprising oxidizing the 3'-hydroxymethyl group of 2,5,6,4",6"-penta-O-acetyl-2"-N-benzyloxycarbonyl-3"-deoxydihydrostreptomy cin as prepared by skilled introduction of amino-protecting group and hydroxyl-protecting group of appropriately selected natures into 3"-deoxydihydrostreptomycin, and then removing the protective groups from the oxidation product, 2,5,6,4",6"-penta-O-acetyl-2"-N-benzyloxycarbonyl-3"-deoxystreptomycin.

Abstract: 3-Amino-2-hydroxy-4-phenylbutanoic acid and esters thereof as well as new derivatives thereof which are related to bestatin in their chemical structure are active to enhance the immune response in living animals.

Abstract: New semi-synthetic antibiotic derivative are formed from N-methanesulfonic acid derivatives of 3-O-demethylistamycin B which are less toxic than the parent 3-O-demethylistamycin B and retain usefully high antibacterial activity of the parent antibiotic. The new derivatives are produced by a method of N-sulfomethylation where 3-O-demethylistamycin B is reacted with an aldehyde such as paraformaldehyde and sulfurous acid or sulfite reagent.

Abstract: A gallium arsenide static induction transistor of normally-off type simple in manufacture and exhibiting a superior function and suitable for use in low and medium power operation in integrated circuit is obtained by arranging so that its channel region has a length l (.mu.m), a width (.mu.m) and an impurity concentration N (cm.sup.-3), and that the ratio l/w is 0.5-5.0 and that the product Nw.sup.2 is not larger than 2.5.times.10.sup.15 cm.sup.-3..mu.m.sup.2.

Abstract: New semi-synthetic antibiotics, 3"-epistreptomycin and 3"-epidihydrostreptomycin are now provided, which are useful as antibacterial agents. 3"-Epidihydrostreptomycin is produced by a process comprising hydrolyzing an appropriately N,O-protected 2",3"-N,O-carbonyl-3"-epidihydrostreptomycin which is prepared by skilled introduction of amino-protecting groups and hydroxyl-protecting groups of appropriately selected natures into dihydrostreptomycin and intermolecular condensation of a particular pair of amino-protecting and hydroxyl-protecting groups so introduced. 3"-Epistreptomycin is produced by a process comprising oxidizing the 3'-hydroxymethyl group of an appropriately N,O-protected 3"-epidihydrostreptomycin as prepared by skilled introduction of amino-protecting groups and hydroxyl-protecting groups of appropriately selected natures, and then removing the remaining protective groups from the resultant N,O-protected 3"-epistreptomycin obtained as the oxidation product.

Abstract: 2'-Modified kanamycins, including 2'-deoxykanamycin A, 2'-epikanamycin A and 2'-epikanamycin B, as new compounds are produced starting from kanamycin A by consecutive reaction steps. These new compounds are useful as antibacterial agent.

Abstract: An aminoglycoside compound of the following formula ##STR1## wherein one of R.sub.1 and R.sub.2 represents a hydrogen atom and the other, a methyl group, R.sub.3 represents a hydrogen atom or an amino acyl group having 2 to 5 carbon atoms, R.sub.4 represents a lower alkyl group substituted by one or two substituents selected from the class consisting of hydroxy and amino groups, or a hexopyranosyl group whose hydroxy groups may be substituted by amino groups,and a pharmaceutically acceptable acid addition salt thereof; and an antibiotic composition comprising said compound and its pharmaceutically acceptable acid addition salt.

Abstract: Tylosin derivatives shown by the general formula ##STR1## wherein R represents a hydrogen atom or a hydroxyl group; R.sub.1 represents a halogen atom, a hydroxyl group, a tetrahydrofuranyloxy group, a tetrahydropyranyloxy group, a tetrahydrothiofuranyloxy group, a tetrahydrothiopyranyloxy group, an alkanoyloxy group, an arylcarbonyloxy group, an aralkylcarbonyloxy group, a lower alkylthiomethyloxy group, a heterocyclic thio group which may have a substituent, a mono- or di- lower alkylamino lower alkylthio group or a group of ##STR2## (wherein R.sub.4 represents a hydroxyl group or an alkanoyloxy group); R.sub.2 represents a hydrogen atom, a hydroxyl group, or an alkanoyloxy group; R.sub.3 represents a hydroxyl group or an alkanoyloxy group; and represents a single bond or a double bond, but represents a double bond when R.sub.2 is a hydrogen atom.These compounds are useful as antibiotics.

Abstract: A multiplicity of field effect type semiconductor memory elements are formed perpendicular to a surface of a semiconductor wafer. Charge carriers are transported in the semiconductor bulk perpendicular to the surface and a potential barrier is formed in the current path to accomplish storing. Since the bulk mobility of a semiconductor is far larger than the surface mobility, the transit time of the carriers is much improved. Furthermore, since each structure of the memory cells is formed perpendicular to the semiconductor surface, the surface occupation area per memory cell is reduced. Thus, a high-speed and high-density semiconductor memory device is provided.