Abstract: An electronic discussion system including discussion terminals for writing and managing opinion information and clients for accessing the discussion terminals through a network.

Abstract: Provided is a downhole percussion drill, which is installed at an end portion of a drillstring and performs drilling by giving impact blows to a drill bit at the bottomhole, which includes a hydraulic hammering mechanism 7 which uses oil having high lubricating ability as a driving medium, a hydraulic pump 8 which pressurizes the oil, and a downhole motor 9 which drives the hydraulic pump 8.

Abstract: Imidazoquinoline derivatives of the formula ##STR1## (wherein X may be O or S) provide selective cyclic guanosine 3',5' monophosphate (cGMP)--specific phosphodiesterase (PDE) inhibitory activity. The compounds are useful for treating or ameliorating cardiovascular disease such as thrombosis, angina pectoris, hypertension, heart failure and arterial sclerosis, as well as asthma, impotence and the like.

Abstract: Only important portions in all of messages are extracted in the halfway or after the end of a discussion and are allowed to be referred to the user. The time for discussion is reduced, thereby smoothly proceeding a conference. An electronic conference system is constructed in an electronic conference system server in a manner such that a plurality of user clients are connected to the electronic conference system server through a network (not shown). The electronic conference system is made up of a message database, a message relation extracting unit, a message type setting unit, a message input and display unit, and an electronic conference summarizing system. The electronic conference summarizing system is constructed by a discussion path specifying unit, a message merging unit, a duplication message deleting unit, and a message summary file.

Abstract: An electronic discussion system of the client/server structure for an electronic exchange of messages which are presented by a plurality of users and shown on a display of a client computer, wherein the servers comprise at least one storage server for holding detailed contents of respective pieces of opinion information, and at least one discussion server for holding opinion indexes showing the storage locations of opinion contents of respective pieces of opinion information, wherein the clients comprise an opinion writing client for transferring and writing the opinion index created from a newly presented piece of opinion information and the opinion content into the discussion server and the storage server, and a reading client for referring to opinion indexes and opinion contents recorded and managed in the discussion server and the storage server.

Abstract: The present invention relates to imidazoquinazoline derivatives represented by formula (I): ##STR1## wherein R.sup.1 represents hydrogen, substituted or unsubstituted lower alkyl, cycloalkyl, lower alkenyl, substituted or unsubstituted aralkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroarylalkyl, or substituted or unsubstituted heteroaryl, R.sup.2 and R.sup.3 represent independently hydrogen, substituted or unsubstituted lower alkyl, substituted or unsubstituted aralkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroarylalkyl, or substituted or unsubstituted heteroaryl, or R.sup.2 and R.sup.3 are combined to represent a heterocyclic group containing a nitrogen atom, R.sup.4 represents hydrogen or substituted or unsubstituted lower alkyl, X represents O or S, Y represents a single bond or O, n represents 0, 1, 2, or 3, and pharmaceutically acceptable salts thereof.

Abstract: The present invention relates to imidazoquinazoline derivatives represented by the general formula (I): ##STR1## or pharmacologically acceptable salts thereof. The compounds of the present invention have strong and selective cGMP-specific PDE inhibitory activity and are useful for treating or ameliorating cardiovascular diseases such as thrombosis, angina pectoris, hypertension, arterial sclerosis and the like, as well as asthma and the like.

Abstract: Disclosed is a peptide compound represented by the following formula (I):R.sup.1 -R.sup.2 -R.sup.3 -R.sup.4 -R.sup.5 -R.sup.6 -R.sup.7 -R.sup.8 -R.sup.9 -R.sup.10 -R.sup.11 -R.sup.12 -Phe-R.sup.14 -R.sup.15 -R.sup.16 -R.sup.17 -R.sup.18 -Ile-R.sup.20 -Z SEQ. ID NO. 64, (I)wherein R.sup.1-12, R.sup.14-18, and R.sup.20 are as defined in the specification.

Abstract: A tricyclic compound represented by the following formula (I): ##STR1## exhibits antagonism to angiotensin II receptors.

Abstract: Novel xanthine compounds represented by the following formula: ##STR1## wherein each of R.sup.1, R.sup.2 and R.sup.3 independently represents hydrogen or lower alkyl;each of X.sup.1 and X.sup.2 independently represents oxygen or sulfur; and Q represents: ##STR2## The compounds are useful as a diuretic, a renal-protecting agent and bronchodilator.

Abstract: A tricyclic compound represented by the following formula (I): ##STR1## wherein R.sup.1 represents hydrogen, halogen or lower alkyl; A represents cyano, carboxyl, tetrazolyl, cyano-substituted phenyl, carboxyl-substituted phenyl or tetrazolyl-substituted phenyl; V represents --(CH.sub.2).sub.m --(wherein m is an integer of 0 to 2); W represents ##STR2## (wherein R.sup.2, R.sup.3 and R.sup.4 independently represent hydrogen, halogen, lower alkyl, cycloalkyl, halogenated lower alkyl, hydroxy, lower alkoxy, amino, lower alkylamino, carboxyl or lower alkoxycarbonyl; and Q.sup.1 --Q.sup.2 --Q.sup.3 --Q.sup.4 represents N.dbd.CH--CH.dbd.CH; X.sup.1 --X.sup.2 --X.sup.3 represents CH.dbd.CH--CH.dbd.CH, S--CH.dbd.CH or CH.dbd.CH--S; Y represents a single bond, CH.sub.2, O, S, CH.sub.2 O, OCH.sub.2, CH.sub.2 S, SCH.sub.2, CH.sub.2 CH.sub.2 or CH.dbd.CH; and Z.sup.1 --Z.sup.2 represents C.dbd.CH, CH--CH.sub.2 or CH--CH(COOH)-- or a pharmaceutically acceptable salt thereof.

Abstract: A tricyclic compound represented by the following formula (I): ##STR1## wherein R.sup.1 represents hydrogen, halogen or lower alkyl; A represents cyano, carboxyl, tetrazolyl, cyano-substituted phenyl, carboxyl-substituted phenyl or tetrazolyl-substituted phenyl; V represents --(CH.sub.2).sub.m -- wherein m is an integer of 0 to 2; W represents ##STR2## and Q.sup.1 --Q.sup.2 --Q.sup.3 --Q.sup.4 represents N.dbd.CH--CH.dbd.CH, CH.dbd.CH--CH.dbd.CH or CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2, ##STR3## and Q represents N or CH; X.sup.1 --X.sup.2 --X.sup.3 represents CH.dbd.CH--CH.dbd.CH, S--CH.dbd.CH or CH.dbd.CH--S; Y represents CH.sub.2 CH.sub.2 ; and Z.sup.1 --Z.sup.2 represents N--(CH.sub.2).sub.n -- wherein n is an integer of 1 to 3 or a pharmaceutically acceptable salt thereof.

Abstract: Novel xanthine compounds represented by the following formula: ##STR1## wherein each of X.sup.1 and X.sup.2 independently represents oxygen or sulfur; and Q represents; ##STR2## where ----- represents a single bond or a double bond; Y represents a single bond or alkylene, n represents 0 or 1, each of W.sup.1 and W.sup.2 independently represents hydrogen, lower alkyl or amino, Z represents --CH.sub.2 -, --O--, --S-- or --NH--; represents ##STR3## each of R.sup.1 and R.sup.2 independently represents hydrogen, lower alkyl, allyl or propargyl; and R.sup.3 represents hydrogen or lower alkyl, and when Q represents the groups other than ##STR4## each of R.sup.1, R.sup.2 and R.sup.3 independently represents hydrogen or lower alkyl;provided that when Q is ##STR5## then R.sup.1 R.sup.2 and R.sup.3 are notsimultaneously methyl; and pharmaceutically acceptable salts thereof have a diuretic effect, a renal-protecting effect and a bronchodilatory effect.

Abstract: There are disclosed condensed purine derivatives represented by formula; ##STR1## in which R.sup.3 represents hydrogen, lower alkyl or benzyl; each of X.sup.1 and X.sup.2 independently represents hydrogen, lower alkyl, aralkyl or phenyl; and n is an integer of 0 or 1; R.sup.1 represents hydrogen, lower alkyl, alicyclic alkyl, noradamantan-3-yl, dicyclopropylmethyl or styryl; and R.sup.2 represents hydrogen, lower alkyl or alicyclic alkyl; or a pharmaceutically acceptable salt thereof. The derivatives and pharmaceutically acceptable salts are useful as diuretics, renal protecting agents, antiallergic agents and hypotensives.

Abstract: There are disclosed s-triazolo[3,4-i]purine derivatives represented by formula: ##STR1## wherein Y-Z represents ##STR2## R.sub.4 represents hydrogen, alkyl, substituted or unsubstituted aromatic heterocyclic group or substituted or unsubstituted aryl; and X.sup.2 represents oxygen, sulfur or NH; each of R.sup.1 and R.sup.2 independently represents hydrogen, alkyl, cycloalkyl, aralkyl or substituted or unsubstituted aryl; R.sup.3 represents alkyl, cycloalkyl, aralkyl or substituted or unsubstituted aryl; X.sup.1 represents oxygen or sulfur; and represents a single bond or a double bond or pharmaceutically acceptable salts thereof.

Abstract: Novel xanthine compounds represented by the following formula: ##STR1## and pharmaceutically acceptable salts thereof have a diuretic action, a renal-protecting action and a vasodilative action.The compounds are useful as a diuretic, a renal-protecting agent and an antihypertensive agent.

Abstract: Compounds of the formula ##STR1## wherein R.sub.3 is H or alkyl, Q.sub.1 and Q.sub.2 are independently hydrogen, alkyl, hydroxyl, alkoxyl, amino, mono or di alkylamino, nitro or halo or pharmaceutically acceptable salts are useful as cardiotonics.

Abstract: Quinazoline derivatives and their pharmaceutically acceptable acid addition salts having the general formula ##STR1## wherein R.sup.1 and R.sup.2 each represents hydrogen or alkyl;R.sup.3 represents alkyl or substituted alkyl;R.sup.7 and R.sup.8 each represent alkoxy;Z is oxygen or sulfur;m is zero or 1;n is zero or an integer from 1 to 5,exhibit a cardiotonic activity with little tendency to cause tachycardia.