Abstract: Disclosed are: a novel purine derivative, a composition thereof, a method for treating tumor using the purine derivative, and an antitumor agent using the purine derivative. Specifically disclosed is a compound represented by formula (I), or a pharmaceutically acceptable salt, solvate or hydrate thereof, or a prodrug thereof.

Abstract: [Problem] To provide a prophylactic/therapeutic agent against, for example, nerve diseases and the like such as ischemic brain disease and neurodegenerative disease, or a prophylactic/therapeutic agent against diseases against which antioxidant action is effective, as a cell protecting agent, in particular as an inhibitor of brain cell damage or brain cell death.

Abstract: Disclosed are: a novel purine derivative, a composition thereof, a method for treating tumor using the purine derivative, and an antitumor agent using the purine derivative. Specifically disclosed is a compound represented by formula (I), or a pharmaceutically acceptable salt, solvate or hydrate thereof, or a prodrug thereof.

Abstract: [Problem] To provide a prophylactic/therapeutic agent against, for example, nerve diseases and the like such as ischemic brain disease and neurodegenerative disease, or a prophylactic/therapeutic agent against diseases against which antioxidant action is effective, as a cell protecting agent, in particular as an inhibitor of brain cell damage or brain cell death.

Abstract: A method of sealing a liquid container, including filling a liquid into a liquid containing bag including a cylindrical inlet; and sandwiching the cylindrical inlet with a pair of heat-sealing heads upon application of heat such that the cylindrical inlet is sealed with the liquid therein, wherein at least one of the pair of heat-sealing heads comprises a concave edge.

Abstract: A method of sealing a liquid container, including filling a liquid into a liquid containing bag including a cylindrical inlet; and sandwiching the cylindrical inlet with a pair of heat-sealing heads upon application of heat such that the cylindrical inlet is sealed with the liquid therein, wherein at least one of the pair of heat-sealing heads comprises a concave edge.

Abstract: An optical transmission system includes a current source for outputting a drive current, a semiconductor laser for converting the drive current into a stimulated emission light and producing the same, a drive circuit for converting a transmission data signal into a modulation control signal and outputting the same, an optical modulator for receiving the stimulated emission light and a shading control signal for interrupting light emission and producing and outputting transmission signal light by changing an amount of transmission of the stimulated emission light according to the shading control signal, and a shading element for receiving the transmission signal light and a shading control signal for interrupting light emission and interrupting the transmission of the transmission signal light according to the shading control signal whereby an optical signal having wrong optical wavelength is rapidly prevented.

Abstract: An optical transmission system includes a current source for outputting a drive current, a semiconductor laser for converting the drive current into a stimulated emission light and producing the same, a drive circuit for converting a transmission data signal into a modulation control signal and outputting the same, an optical modulator for receiving the stimulated emission light and a shading control signal for interrupting light emission and producing and outputting transmission signal light by changing an amount of transmission of the stimulated emission light according to the shading control signal, and a shading element for receiving the transmission signal light and a shading control signal for interrupting light emission and interrupting the transmission of the transmission signal light according to the shading control signal whereby an optical signal having wrong optical wavelength is rapidly prevented.

Abstract: A speech detection apparatus capable of reliably detecting speech segments in audio signals regardless of the levels of input audio signals and background noises. In the apparatus, a parameter of input audio signals is calculated frame by frame, and then compared with a threshold in order to judge each input frame as one of a speech segment and a noise segment, while the parameters of the input frames judged as the noise segments are stored in the buffer and the threshold is updated according to the parameters stored in the buffer. The apparatus may utilize a transformed parameter obtained from the parameter, in which the difference between speech and noise is emphasized, and noise standard patterns are constructed from the parameters of the input frames pre-estimated as noise segments.