• Title/Summary/Keyword: Central action

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A Case Study on the Management System of World Natural Heritage in Japan (일본의 세계자연유산 관리 체계에 관한 사례 연구)

  • Lee, Chang-Hun;Park, Jin-Wook
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.38 no.1
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    • pp.142-151
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    • 2020
  • This study is designed to deduce an implication for an effective implementation of the Special Act for Conservation, Management and Utilization of World Heritage in Korea which was legislated in February, 2020. To draw an implication, which is regarded as highly valuable for preparing for the implementation of the act, several case studies were performed focusing on four World Natural Heritage sites in Japan, and the result is as follows. First, it is enormously crucial for the central administration agencies and the local government to have a system through which they communicate one another regularly. All the target areas in Japan consist of three national parks and a prefectural park with natural monuments, and the national forest covers a tremendously large proportion of the areas. The Japanese central agencies including Ministry of the Environment, Forestry Agency and Agency for Cultural Affairs have communication with the local government through a system named Regional Liaison Committee in order to manage the sites effectively. Also, in the case of Japan, de facto administrating agencies involving non-profit organizations and the tourism association also participate in the regular conferences to communicate. Second, a specific committee consisting of academic advisers is strongly needed. In the case of Japan, Scientific Committee provides academic grounds for the management plan established by the members of Regional Liaison Committee, and an active system which allows the members to organize consultative committees and subcommittees has been established. Scientific Committee plays an important role in preventing the local government, which tends to manage the world natural heritage in more economically profitable ways, from damaging the environment of the site. The establishment of this type of committee is thought to be extremely desirable because the World Natural Heritage requires comprehensive and sustainable management plans on the ecosystem. Third, establishment of comprehensive management plan based on continuous monitoring on the environment and detailed action plan is exceedingly needed. To sum up, it is vital to establish a management plan considering environmental aspect, and detailed guidelines, which help execute the plan both properly and effectively, are required for systematic and sustainable management.

Studies on the Changes in Heart Rate and Blood Pressure Induced by Central Norepinephrine and Clonidine (뇌내(腦內) Norepinephrine, Clonldine에 의한 심박(心搏) 및 혈압변동(血壓變動)에 관한 연구(硏究))

  • Lee, Jung-Chung
    • The Korean Journal of Pharmacology
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    • v.14 no.1_2
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    • pp.13-23
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    • 1978
  • 1) It was attempted to clarify the sites of action of central (either intraventricular or intracisternal) norepinephrine(NE) and clonidine to cause cardiac slowing and hypotension in urethane-anesthetized rabbits. 2) NE produced cardiac slowing but indistinct effect on blood pressure. Clonidine produced cardiac slowing and hypotension. 3) Intraventricular and intracisternal administration of NE, clonidine, phenylephrine and isoproterenol did not make difference in their effects, except that the onset of cardiac slowing by intracisternal NE was more rapid than intraventricular NE. 4) Upon repeated administration of NE at the intervals of about two hours, blood pressure responses changed to the pressor ones, the cardiac slowing unchanged. By this procedure the cardiac slowing as well as the hypotension by clonidine were gradually diminished. 5) Clonidine, when given during the NE effects were persisting, did not produce the lowering of blood pressure and further decrease of heart rate. NE, when given during the clonidine effects were persisting, produced marked elevation of blood pressure but did not produce further decrease of heart rate. 6) After intraventricular administration of regitine or desmethylimipramine, the cardiac slowing effect of NE and the clonidine effects were not observed, whereas NE produced marked elevation of blood pressure. 7) Reserpinized rabbits showed pressor and cardiac accelerating responses to NE; slight pressor, and little cardiac responses to clonidine. 8) It seems that the cardiac slowing by both clonidine and NE as well as the hypotetsion by clonidine are mediated by the presynaptic ${\alpha}$-adrenoceptor in the brain but the pressor responses to NE and clonidine are mediated by other site(s) than the presynaptic ones.

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Pharmacological Evaluation of the Mechanism of ${\alpha}-Adrenoceptor-Mediating$ Sleep in Chickens (${\alpha}$-아드레나린 수용체의 매개에 의한 병아리 수면에 대한 약리학적 고찰)

  • Jeong, S.H.;Sohn, U.D.;Song, C.S.;Hong, K.W.
    • The Korean Journal of Pharmacology
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    • v.20 no.2
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    • pp.15-21
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    • 1984
  • It was aimed to study the effects of ${\alpha}_2-adrenoceptor$ agonists on the sleeping time in $one{\sim}two-day-old$ chickens. Furthermore, it was also evaluated whether ${\alpha}_1-adrenoceptor$ agonist and antagonist might affect the sleeping in the chickens and discussed in relation with opiate receptor. 1) Guanabenz, clonidine, guanfacine and B-HT 933 decreased the latency of the loss of righting reflex in a dose-dependent manner, but B-HT 920 and oxymetazoline slightly prolonged it. 2) ${\alpha}_2-Adrenoceptor$ agonists produced dose·related increase in sleeping time. The potency was guanabenz>clonidine>oxymetazoline${\geq}$B-HT 933${\geq}$B-HT 920>guanfacine in this order. 3) ${\alpha}_2-Adrenoceptor$ antagonists decreased guanabenz-induced sleeping time in a dose ·dependent manner. The rank order of ${\alpha}_2-adrenoceptor$ antagonists was yohimbine>rauwolscine>piperoxan${\geq}$RX 781094. 4) Sleeping time caused by both ethanol and hexobarbital was not affected by yohimbine in chickens. 5) Methoxamine and phenylephrine showed little significant effect on the guanabenz-induced sleeping time. However, prazosin increased it. Paradoxically, corynanthine rather caused to decrease it. These results suggest that the stimulation of central ${\alpha}_2-adrenoceptor$ mediates sleeping, however it is remained uncertain in the role of central ${\alpha}_1-adrenoceptor$ in chickens. In addition, the one~two-day-old chickens may be considered as a useful, inexpensive and simple experimental model to evaluate the in vivo pharmacological action of the ${\alpha}_2-adrenoceptor$ agonist and antagonist related to sedation.

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Electronic Roll Book using Electronic Bracelet.Child Safe-Guarding Device System (전자 팔찌를 이용한 전자 출석부.어린이 보호 장치 시스템)

  • Moon, Seung-Jin;Kim, Tae-Nam;Kim, Pan-Su
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.143-155
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    • 2011
  • Lately electronic tagging policy for the sexual offenders was introduced in order to reduce and prevent sexual offences. However, most sexual offences against children happening these days are committed by the tagged offenders whose identities have been released. So, for the crime prevention, we need measures with which we could minimize the suffers more promptly and actively. This paper suggests a new system to relieve the sexual abuse related anxiety of the children and solve the problems that electronic bracelet has. Existing bracelets are only worn by serious criminals, and it's only for risk management and positioning, there is no way to protect the children who are the potential victims of sexual abuse and there actually happened some cases. So we suggest also letting the students(children) wear the LBS(Location Based Service) and USN(Ubiquitous Sensor Network) technology based electronic bracelets to monitor and figure out dangerous situations intelligently, so that we could prevent sexual offences against children beforehand, and while a crime is happening, we could judge the situation of the crime intelligently and take swift action to minimize the suffer. And by checking students' attendance and position, guardians could know where their children are in real time and could protect the children from not only sexual offences but also violent crimes against children like kidnapping. The overall system is like follows : RFID Tag for children monitors the approach of offenders. While an offender's RFID tag is approaching, it will transmit the situation and position as the first warning message to the control center and the guardians. When the offender is going far away, it turns to monitoring mode, and if the tag of the child or the offender is taken off or the child and offender stay at one position for 3~5 minutes or longer, then it will consider this as a dangerous situation, then transmit the emergency situations and position as the second warning message to the control center and the guardians, and ask for the dispatch of police to prevent the crime at the initial stage. The RFID module of criminals' electronic bracelets is RFID TAG, and the RFID module for the children is RFID receiver(reader), so wherever the offenders are, if an offender is at a place within 20m from a child, RFID module for children will transmit the situation every certain periods to the control center by the automatic response of the receiver. As for the positioning module, outdoors GPS or mobile communications module(CELL module)is used and UWB, WI-FI based module is used indoors. The sensor is set under the purpose of making it possible to measure the position coordinates even indoors, so that one could send his real time situation and position to the server of central control center. By using the RFID electronic roll book system of educational institutions and safety system installed at home, children's position and situation can be checked. When the child leaves for school, attendance can be checked through the electronic roll book, and when school is over the information is sent to the guardians. And using RFID access control turnstiles installed at the apartment or entrance of the house, the arrival of the children could be checked and the information is transmitted to the guardians. If the student is absent or didn't arrive at home, the information of the child is sent to the central control center from the electronic roll book or access control turnstiles, and look for the position of the child's electronic bracelet using GPS or mobile communications module, then send the information to the guardians and teacher so that they could report to the police immediately if necessary. Central management and control system is built under the purpose of monitoring dangerous situations and guardians' checking. It saves the warning and pattern data to figure out the areas with dangerous situation, and could help introduce crime prevention systems like CCTV with the highest priority. And by DB establishment personal data could be saved, the frequency of first and second warnings made, the terminal ID of the specific child and offender, warning made position, situation (like approaching, taken off of the electronic bracelet, same position for a certain time) and so on could be recorded, and the data is going to be used for preventing crimes. Even though we've already introduced electronic tagging to prevent recurrence of child sexual offences, but the crimes continuously occur. So I suggest this system to prevent crimes beforehand concerning the children's safety. If we make electronic bracelets easy to use and carry, and set the price reasonably so that many children can use, then lots of criminals could be prevented and we can protect the children easily. By preventing criminals before happening, it is going to be a helpful system for our safe life.

The Effect of Lidocaine Dose and Pretreated Diazepam on Cardiovascular System and Plasma Concentration of Lidocaine in Dogs Ansthetized with Halothane-Nitrous Oxide (Diazepam 전투여와 Lidocaine 투여용량이 혈중농도 및 심혈역학적 변화에 미치는 영향)

  • Lee, Kyeong-Sook;Kim, Sae-Yeon;Park, Dae-Pal;Kim, Jin-Mo;Chung, Chung-Gil
    • Journal of Yeungnam Medical Science
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    • v.10 no.2
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    • pp.451-474
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    • 1993
  • Lidocaline if frequently administered as a component of an anesthetic : for local or regional nerve blocks, to mitigate the autonomic response to laryngoscopy and tracheal intubation, to suppress the cough reflex, and for antiarrythmic therapy. Diazepam dectease the potential central nervous system (CNS) toxicity of local anesthetic agents but may modify the sitmulant action of lidocaine in addition to their own cardiovascular depressant. The potential cardiovascular toxicity of local anesthetics may be enhanced by the concomitant administration of diazepam. This study was designed to investigate the effects of lidocaine dose and pretreated diazepam to cardiovascular system and plasma concentration of lidocaine. Lidocaine in 100 mcg/kg/min, 200 mcg/kg/min, and 300 mcg/kg/min was given by sequential infusion to dogs anesthetized with halothane-nitrous oxide (Group I). And in group II, after diazepam pretreatment, lidocaine was infused by same way when lidocaine was administered in 100 mcg/kg/min, the low plasma levels ($3.97{\pm}0.22-4.48{\pm}0.36$ mcg/ml) caused a little reduction in cardiovascular hemodynamics. As administered in 200 mcg/kg/min, 300 mcg/kg/min, the higher plasma levels ($7.50{\pm}0.66-11.83{\pm}0.59$ mcg/ml) reduced mean arterial pressure (MAP), cardiac index (CI), stroke index (SI), left ventricular stroke work index (LVSWI), and right ventricular stroke work index (PVSWI) and increased pulmonary artery wedge pressure (PAWP), central venous pressure (CVP), systemic vascular resistance index (SVRI), but was associated with little changes of heart rate (HR), mean pulmonary artery pressure (MPAP), and pulmonary vascular resistance index (PVRI). When lidocaine with pretreated diazepam was administered in 100 mcg/kg/min, the low plasma level, the lower level than when only lidocaine administered, reduced MAP, but was not changed other cardiovascular hemodynamics. While lidocaine was infused in 200 mcg/kg/min, 300 mcg/kg/min in dogs pretreated diazepam, the higher plasma level ($7.64{\pm}0.79-13.79{\pm}0.82$ mcg/ml) was maintained and was associated with reduced CI, SI, LVSWI and incresed PAWP, CVP, SVRI but was a little changes of HR, MPAP, PVRI. After $CaCl_2$ administeration, CI, SI, SVRI, LVSWI was recovered but PAWP, CVP was rather increased than recovered. The foregoing results demonstrate that pretreated diazepam imposes no additional burden on cardiovascular system when a infusion of large dose of lidocaine is given to dogs anesthetized with halothanenitrous oxide. But caution may be advised if the addition of lidocaine is indicated in subjects who have impared autonomic nervous system and who are in hypercarbic, hypoxic, or acidotic states.

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Pressor Action of Physostigmine in the Rabbit (토끼에 있어서의 Physostigmine의 혈압상승작용)

  • Kim, Je-Bong
    • The Korean Journal of Pharmacology
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    • v.26 no.2
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    • pp.101-111
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    • 1990
  • The effect of physostigmine (PS), which has been shown to act on the muscarinic receptors in the brains of the rat, dog and cat, on the arterial blood pressure (BP) was investigated in urethane-anesthetized rabbits. Intravenous (iv) PS, $25{\sim}300\;{\mu}g/kg$, caused little change in BP. However, after treatment of rabbits with either of chlorisondamine (CS), hexamethonium, intracerebroventricular (icv) clonidine, icv xylazine and icy reserpine iv PS produced a pressor response. Spinalization of the rabbit also caused iv PS to increase BP. The pressor effect of iv PS in CS-treated rabbits was markedly reduced after prazosin or pirenzepine. Iv PS inhibited the pressor response to McN-A-343 in CS-treated and in spinal rabbits; alternately during the infusion of McN-A-343 iv PS failed to produce the pressor response. The pressor response to DMPP was not affected by iv PS. Icv PS, $12{\sim}200\;{\mu}g/kg$, produced a pressor response which was accentuated after CS-treatment. This pressor effect was inhibited, though not complete, by prazosin or by pirenzepine. A simultaneous treatment of rabbits with both $[Sar^{1},\;Ala^{8}]-angiotensin$ II, an angiotensin II antagonist, and prazosin or pirenzepine almost completely abolished the pressor effect of icv PS, whereas the angiotensin II antagonist did not enhance the inhibitory effect of pirenzepine and prazosin on the pressor response to iv PS . Icv pirenzepine blocked the pressor response to icv PS without affecting that to iv PS. The present results show that the pressor response to iv PS in CS-treated and in spinal rabbits arises from stimulation of the muscarinic receptors in the sympathetic ganglia, whereas the pressor response by icv PS via activation of the muscarinic receptors in the brain which causes an enhancement in the outflow of sympathetic discharge and angiotensin. The results also suggest that iv PS is unable to produce a pressor response in the rabbit unless the sensitivity of the gangionic muscarinic receptors is altered by ganglionic nicotinic blockade, by the decrease of central sympathetic outflow on the sympathetic ganglia or by spinalization.

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A study on the Wonju Medical Equipment Industry Cluster (원주의료기기산업 클러스터의 형성과정에 관한 연구)

  • Lee, Woo-Chun;Yoon, Hyung-Ro
    • Journal of the Korean Academic Society of Industrial Cluster
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    • v.1 no.1
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    • pp.67-86
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    • 2007
  • Wonju Medical Equipment Industry, despite of its short history, poor sales and weak manpower and so on, have shown remarkable outcomes in a relatively short period. At the end of 2007, totally 79 enterprises (only 4.6% of whole enterprises in Korea) made 10% of the nationwide production and 15% of the nationwide exports with an annual average growth rate of 66.7%, contributing domestic medical equipment industry tremendously. In addition, many leading medical equipment enterprises in various fields already moved or plan to move to Wonju, accelerating Wonju Medical Equipment Cluster. Wonju Medical Equipment Industry Cluster now enters into the growth stage, getting out of the initial business setup stage. Especially, the nomination of Wonju cluster project from the government accelerates networking (e.g. the development of the universal parts, the establishment of the mutual collaboration model among enterprises, and the mutual marketing), making a rapid growth in Wonju Medical Equipment Industry. Wonju Medical Equipment Industry Cluster revealed positive outcomes despite of the weakness in investment size and infra-structure comparing with the other medical industry cluster in the advanced country, while many domestic enterprises pursued their own growth models and thus failed to promote the international competitive power. Wonju Medical Equipment Industry has been developed rapidly. However, there are many challenging problems to support enterprises: small R&D investment and thus weak technology power, difficulties in recruiting R&D engineers, and poor marketing capabilities, financial infrastructure & policies, and network architecture. In order to develop a world-competitive medical equipment industry cluster at Wonju, the complement of infrastructures, the technology innovation, the mutual marketing, and the network expansion to support enterprises are further required. Wonju' s experiences in developing medical equipment industry so far suggest that our own flexible cluster model considering the industry structure and maturity for different regions should be developed, and specific action plans from the local and central governments based on their systematic strategies for industry development should be implemented in order to build world-competitive industry clusters in Korea.

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Current Status of Korean Ginseng Research (한국인삼론(韓國人蔘論))

  • Han, Byung-Hoon
    • Korean Journal of Pharmacognosy
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    • v.3 no.3
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    • pp.151-160
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    • 1972
  • Recent achievements of scientific research on the pharmacologic activities and the chemical problems of dammalene glycosides, which are considered to be effective principles of Korean ginseng, are reviewed and analyzed in view of structure-activity relationship. 1) S. Shibata and his co-workers detected 12 glycoside spots of dammalene series on the two dimensional T.L.C. of total glycoside fraction from Japanese ginseng, and designated them Ginsenoside Rx(x=a, b, c, g, h, etc.) in the order of increasing Rf-value. The aglycones of those glycosides were characterized to be protopanaxadiol for the Ginsenoside $Rx(x=a,\;b_{1},\;b_{2},\;c,\;d,\;e,\;f)$ and protopanaxatriol for the Ginsenoside $Rx(x=g_{1},\;g_{2},\;g_{3},\;h_{1}\;'h_{2})$. Using Korean ginseng as the material for our study, the author and his coworkers isolated a new dammalene glycoside(Panax Saponin C), which comes under the category of protopanaxadiol glycosides based on the classification of S. Shibata et al., and characterized this saponin to be the glycoside of protopanaxatriol series. Furthermore, Panax Saponin C dissociated into $two\;components(C_{1}\;and\;C_{2}-acetate)$ by acetylation, both of which returned to original Panax Saponin C by deacetylation. Based on this result, more than 13 glycoside components of dammalene series will be expected in the Korean ginseng. 2) The structures of protopanaxadiol and protopanaxatriol, the genuine aglycones of dammalene glycosides, are fully established to be structural analogues by S. Shibata and his co-workers, therefore antagonistic and/or analogical activities will be expected for the pharmacologic activities of these glycoside series of structural analogues. K. Takaki and his co-workers found central nervous system (CNS) stimmulant activity from the glycosides of protopanaxatriol series and CNS-depressant activity from the glycosides of protopanaxadiol series. On the other hand, the author and his co-workers found stimmulating activity on the protein synthesis from both the series of dammalene glycosides with delayed and long-lasting characteristics. This delayed and long-lasting characteristics were also observed in the anti-inflammatory activity of glycosides of protopanaxatriol series on their time course tendency. For the convenience's sake of argument, pluralistic pharmacologic activities of dammalene glycosides, which were observed by many workers at various pharmacologic site, may be classified into two main categories; one is pan-cellular activity and the other is organ specific activity to the certain tissue which is a mass of cells differentiated to a certain direction for their special functions in the body. Based on the data of K. Takaki and those of the authors, following assumption will be probable; Pharmacologic activities of both series of glycosides of protopanaxadiol and protopanaxatriol aglycones may be antagonistic on their tissue-specific activities and analogic on their pan-cellular activities. Therefore, the mixture of these two series of glycosides in an appropriate ratio, as the case of total extract of Korean ginseng, will be probably beneficial to the host by increasing the synthesis of some functional proteins, due to the additive action of pan-cellular activity, and with the disappearance of any significant behavioral symptoms due to the antagonism of tissue specific activity. This fact will probably be the main reason why classical trials of pharmacologists failed in re-discovering the efficacy of Korean ginseng with their behavioral test. 3) The author and his co-workers achieved the synthesis of $C^{14}-labelled\;Panax\;Saponin\;A\;on\;C_{25}-C_{27}\;position\;of\;aglycone$ in the interest of tracer studies in vivo. The method will be applicable to other dammalene glycosides regardless of their chemical structure. 4) The author and his co-workers converted chemically betulafolienetriol, a triterpene component of Betula platyphylla, to the protopanaxadiol, one of genuine aglycone of dammalene glycosides.

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Effect of Cardiotonic Pills$^{(R)}$ on Chest Pain and Discomfort: A Multi-center Double-blind Randomized Controlled Trial. (심적환$^{(R)}$이 흉통 흉민에 대하여 미치는 영향에 대한 다기관 무작위배정 이중맹검 임상연구)

  • Jang Insoo;Ko Changnam;Lee In;Park Jung-mi;Kim Sehyun;Kim Sangwoo
    • The Journal of Korean Medicine
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    • v.26 no.2 s.62
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    • pp.95-104
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    • 2005
  • Objectives: This was a double blinded, randomized, placebo-controlled clinical study for evaluation of safety and effective dose finding of Cardiotonic Pills$^{(R)}$ in patients with chest pain and discomfort. Cardiotonic Pills$^{(R)}$ are composed of Salviae Miltiorrhizae Radix (丹蔘), Notoginseng Radix (三七根) and Borneolum (龍腦). Major effects of Salviae Miltiorrhizae Radix and Notoginseng Radix are vasodilatation, sedation and analgesic action. Borneolum has an antibacterial effect, and can stimulate the central nervous system. All of these substances are oriental herbs that have been used for a long time in east Asia. Cardiotonic Pills fi received Investigational New Drug (IND) approval from the Food and Drug Administration (FDA) in the USA and 40 million people in the world take this pill. We performed a phase IV clinical study to confirm its efficacy and safety in patients who have probable cardiogenic or psychogenic chest pain or chest stifling. Methods: This study was planned for a multi-center clinical trial including four university hospitals of oriental medicine in Korea. This was the first time to evaluate the 'planning treatment according to diagnosis (辨證施治)' of chest pain or chest discomfort according to oriental medical guidelines. The patients who were included in this trial were adult volunteers from 20 to 70 years old who had chest pain or chest discomfort more than twice during a recent month, and we received written consent to participate in this study from all of them. After administration of Cardiotonic Pills$^{(R)}$ for 8 weeks, number of occurrences, duration, appearance and degree of chest pain or chest discomfort was observed and degree of symptoms (severity of illness, global improvement) were measured using a patient's global assessment composite scale. Results: In the patient's global assessment scale, the severity of illness of the Cardiotonic Pills$^{(R)}$ group (n=25) was 14/25=0.56 but of the placebo group (n=25) was 7/25=0.28 (p-value=0.0449). This result indicates Cardiotonic Pills$^{(R)}$have a positive effect on the symptoms of chest pain and discomfort. However, the global improvement of the Cardiotonic Pills$^{(R)}$group was 23/25=0.92, and of the placebo group was 22/25=0.88 (p-value=0.6374). The total symptom score of the Cardiotonic Pills$^{(R)}$ group was $1.68\pm20.06$, and of the placebo group was $16.76\pm72.l4$(p-value=0.2285). The number of symptom events of the Cardiotonic Pills$^{(R)}$ group was $72\pm29.78$, and of the placebo group (n=25) was $10.80\pm38.42$ (p­value=0.3660). We could not find any effects on the other factors examined besides the severity of illness, beyond the difference of standard deviations. Conclusions: Cardiotonic Pills$^{(R)}$ significantly reduced chest pain and chest discomfort in patients. Therefore, we expect that Cardiotonic Pills$^{(R)}$ will be helpful for patients with chest pain and chest discomfort not only caused by heart disease but also by other diseases.

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Inhibitory Effects of ${\gamma}$-Aminobutyric Acid on the Contractility of Isolated Rat Vas Deferens (흰쥐의 적출 정관 수축성에 대한 ${\gamma}$-Aminobutyric Acid의 억제작용)

  • Ahn, Ki-Young;Kwon, Oh-Cheol;Ha, Jeoung-Hee;Lee, Kwang-Youn;Kim, Won-Joon
    • Journal of Yeungnam Medical Science
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    • v.9 no.2
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    • pp.382-395
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    • 1992
  • GABA is an inhibitory neurotransmitter in central nervous system and produce sedative, antianxiety and muscle reaxing effects via $GABA_A$ receptor or $GABA_B$ receptor. Recently it is known that GABA is widely distributed throughout peripheral organs and may playa physiological role in certain organ. The vas deferens is innervated by species-difference. These study, therefore, was performed to investigate the mode and the mechanism of action of GABA on the norepiniphrine-, ATP- and electric stimulation-induced contraction of vas deferens of rat. Sprague-Dawley rats were sacrificed by cervical dislocation. The smooth muscle strips were isolated from the prostastic portion and were mounted in the isolated muscle bath. PSS in the bath was aerated with 95/5%-$O_2/CO_2$ at $33^{\circ}C$. Muscle tensions were measured by isometric tension transducer and were recorded by biological recording system. 1. GABA, muscimol, a $GAB_A$ agonist, and baclofen, a $GABA_B$ agonist inhibited the electric field stimulation(EFS, 0.2Hz, 1mSec, 80 V, monophasic square wave)-induced contraction with a rank order of potency of GABA greater than baclofen greater than muscimol. 2. The inhibitory effect of GABA was antagonized by delta aminovaleric acid(DAVA), a $GABA_B$ antagonist, but not by bicuculline, a $GABA_A$ mtagonist. 3. The inhibitory effect of baclofen was antagonized by DAVA, but the effect of muscimol was not antagonized by bicuculline. 4. Exogenous norepinephrine(NE) and ATP contracted muscle strip concentration dependently, but the effect of acetylcholine was negligible : and GABA did not affect the NE-and ATP-induced contractions. 5. GABA, baclofen and muscimol did not affect basal tone, and GABA did not affect the NE-and ATP-induced contractionsm 6. EFS-induced contraction was including 2 distinctable components. The first phasic component was inhibited by beta gamma-methylene ATP(mATP), a desensitizing agent of APT receptor and the second tonic component was reduced by pretreatment of reserpine(3 mg/Kg, IP). 7. GABA inhibited the EFS-induced contraction of reserpinized strips, but not the mATP-treated strips. These results suggest that in the prostatic portion of the rat vas deferens, adrenergic and purinergic neurotransmissions are exist, and GABA inhibits the release of ATP via presynaptic $GABA_B$ receptor on the excitatory neurons.

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