• The Korean Journal of Physiology and Pharmacology
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• v.4 no.4
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• pp.275-281
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• 2000

Cholecystokinin (CCK) is a gastrointestinal hormone which plays an important role in satiety and gastric motility. It is also widely distributed throughout the central nervous system, where it appears to be involved in the central control of anxiety, feeding behavior and nociception. Two distinct CCK receptor types, $CCK_A$ and $CCK_B,$ have been found in the brain. Both CCK receptors coexist in the rat nucleus tractus solitarius (NTS), which is the primary center for the coordination of peripheral and central activities related to gastrointestinal, cardiovascular and respiratory functions. In order to study ionic actions of CCK on each type of receptor, we investigated the effects of CCK-8S on neurons located in the NTS of the rat using whole-cell patch-clamp recordings in brainstem slices. Application of CCK-8S, under current clamp, produced a membrane depolarization accompanied by action potential firing. This CCK-evoked excitation was dose-dependent $(10\;nM{\sim}10\;{\mu}M)$ and observed in more than 60% of NTS neurons. Under voltage clamp conditions, CCK-8S induced an inward current with a notably increased spontaneous excitatory synaptic activity. However, CCK-8S did not significantly change the amplitude of pharmacologically isolated and evoked EPSP(C)s. Using selective $CCK_A$ and $CCK_B$ receptor antagonists, we observed two different effects of CCK-8S, which suggest $CCK_A$ receptor-mediated inhibitory and $CCK_B$ receptor-mediated excitatory effects in the NTS. These results may help to explain the ability of CCK to modulate gastrointestinal and other reflex systems in the NTS.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.360-367
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• 2006

In this paper, we design the complementary code keying (CCK) modulation/demodulation structure that is proposed in the IEEE 820.11b and IEEE 802.11g. And, this paper proposes the CCK Rake receiver to be fitted for the large delay spread case like the inter-vehicle communications. The channel estimation of each path in the multipath Rayleigh fading channel is done using the packet preamble and, the combining of the multipath signals in the coherent CCK Rake receiver is achieved as the symbol level combining type. In this paper, in order to validate the utilization of CCK modem for the inter-vehicle communications of the telematics communications, we suggest the CCK modem performance that is made for the multipath Rayleigh fading channel with the mobile speed of 300km/h.

• Journal of Acupuncture Research
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• v.24 no.2
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• pp.101-112
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• 2007

목적 : CCK는 현재까지 가장 많이 연구된 식후의 포만신호 전달물질로, 음식섭취를 감소하고, 캡사이신 반응성의 미주신경에 의해 위장운동과 위내의 공복감을 억제시킨다 전침의 진통효과 발현기전에 영향을 미치는 항아편양 단백물질로서, 내인성 CCK와 그 수용체(CCK-A와 CCK-B)의 역할은 기존의 연구에서 이미 보고되어 왔다. 이에 착안하여， 본 연구에서는 포만감의 측면에서 전침자극이 내인성 CCK의 발현에 어떠한 영향을 미치는가를 살펴보고자 한다. 방법 : 48시간 절식 쥐 모델을 이용하여, 전침자극 후 30분과 60분 동안, 먹이 섭취량 변화를 측정하고, 먹이섭취량에 영향을 주는 신경전달경로에서 CCK가 관여하는지를 확인하기 위해 미주신경절제술을 시행한 쥐와 비교하였다. 한편 48시간 절식 쥐 모델을 대상으로하여 침자극 후 시상하부의 CCK mRNA 발현변화를 관찰하였다. 결과 : 전침군에서 30분과 60분 뒤의 먹이 섭취가 대조군에 비해 현저히 낮게 관찰되었는데, 포만감에 관련된 침의 이와 같은 효과는 CCK 수용체에 길항작용이 있는 lorglumide와 미주신경절제술에 의해 차단됨을 알 수 있었다. 시상하부의 CCK mRNA의 발현되는 대조군에 비하여 전침군에서 증가하는 경향이 관찰되었으나, 통계학적인 유의성은 확인 할 수 없었다. 결론 : 위의 결과에서, 전침은 포만감에 영향을 미치는 내인성 CCK 메카니즘을 활성화시키는 것을 알수 있었다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.5C
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• pp.329-337
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• 2005

In this paper, we propose a new type of RAKE receiver for complementary code keying (CCK) codes, which is suitable for the multipath channel with large delay spread. Our proposed system is based on channel matched filter (CMF) with decision feedback equalizer (DFE) and contains codeword DFE structure. In our system, inter chip interference (ICI) and inter symbol interference (ISI) generated due to multipath environments are calculated by using detected CCK codeword. Also it uses the error correcting capability of CCK codes, and it can remove ISI and ICI at the same time.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.766-769
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• 2002

In this paper, we propose new orthogonal modulation method to enhance the performance of CCK adapted in 802.l1b WLAN. To maintain the orthogonality of codewords produced by CCK modulator, we devide 256 codewords into 8 subset by trellis coding and codewords On a subset are orthogonal each other. In result, this method restricts maximum data rate to 9.625Mbps, however, it is better about 1.5dB than original UK modulation at BER 10$^{-5}$ .

• Korean Journal of Poultry Science
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• v.17 no.2
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• pp.83-91
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• 1990

The effect of dietary components on cholecystokinin (CCK) release into plasma was investigated in chicks by feeding a meal through a stomach tube, followed by the CCK determination with specific CCK-8 antibody. In experimental 1, the results showed that both isolated soya protein and an amino acid mixture simulating the amino acid composition of the soya protein increased the release of CCK, though to a lesser extent with a delayed response in the former, when added to a protein-free diet. Among amino acids added singly to the protein-free diet, phenylalanine was more efficient than arginine and valine, exerting a response almost identical to the complete amino acid mixture. In experimental 2 and 3, by feeding the protein diets supplemented SBTI, piasma CCK level was promptly increased and this response was in a dose dependent fashion during the measurement time, being higher at 1000 than at 100 mg/kg diet. Since the SBTI supplementation did not affect crop emptying rates significantly, it was concluded that SBTI by itself enhanced CCK release into circulation.

• Korean Journal of Poultry Science
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• v.16 no.4
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• pp.219-232
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• 1989

The present study was done to investigate the mechanism of Pancreatic digestive enzyme secretion in response to dietary components in chicks. A simplefied pancreatic juice collection method, useful for a short-term experiment, was developed. By wing vein injection, it was shown that the increased trypsinogen and chymotrypsinogen, while neither other single amino acids nor glucose affected the secretion of enzymes, amylase, trypsinogen and chymotrypsinogen. Cholecystokinin (CCK) had an immediate effect on pancreatic enzyme secretion and this response was in a dose dependent fashion. The injection of CCK seemed to have selective stimulation favoring the secretion of chymotrypsinosen followed by amylase and trypsinogen. Simultaneous injection of single amino acid with CCK increased digestive enzyme secretion to various extents depending on the kind of amino acids whereas the injection of glucose with CCK did not affect when compared with that of CCK'alone. By varying doses, synergetic action of CCK plus amino acid on the secretion of pancreatic digestive enzymes was observed at 0.5mM for Val and 5mM for Arg. A further attempt was made to examine the effect of combined administration of amino acids with CCK on pancreatic enzyme secretion. The injected substances were an AAs mixture and combination of selected amino acids, i.e. Thr＋Phe＋Ile, Thr＋Phe. Thr＋Ile or Phe＋Ile. When increases in enzyme outputs for the first 30 min were compared , it was shown that the responses of three enzymes, amylase, trypsinogen and chymotrypsinogen, brought about by the administration of the AAs mixture was almost entirely accounted for by the combined injection of Thr＋Phe. Thus, it was well demonstrated that CCK and amino acids had a synergetic action on the secretion of a specific pancreatic digestive enzyme depending on a kind of amino acid injected.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.645-648
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• 2004

In this paper, we drive a theoretical performance of complementary code keying (CCK) codes on additive white Gaussian noise (AWGN) channel. The CCK codes can be demodulated by the optimal maximum likelihood decoding method and sub-optimal correlation magnitude decoding algorithm. We calculate the bit error rate (BER) and symbol or codeword error rate (SER) of the CCK codes using the above mentioned two decoding algorithms. To derive the error performance, we use the weigh distributions and cross-correlation distributions of CCK codes.

• The Korean Journal of Pharmacology
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• v.16 no.1 s.26
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• pp.35-39
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• 1980

In this study, the effects of phenoxybenzamine and related drugs on the action of CCK-PZ and caerulein were examined in isolated gall bladder of guinea pig and higher esophagus strip of fowl. The strips were placed in a bath containing Locke-Ringer solution maintained at $38^{\circ}C$. Oxygen was continuously bubbled through the solution. The contractile response was measured isometrically by a force displacement transducer connected to polygraph. In isolated gall bladder preparation caerulein produced contractile response of CCK-PZ type, but the relative potency on a weight basis was 30 times stronger than CCK-PZ. The response of caerulein or CCK-PZ was not blocked by cholinergic blocking agent and both alpha and beta adrenergic blockades, however, the response of caerulein or CCK-PZ was exceptionally blocked by phenoxybenzamine. In isolated esophagus strip CCK-PZ with high concentration produced marked contraction which was not modified by atropine and other blocking agents, whereas the response was blocked by phenoxybenzamine. These results lead to the conclusion that phenoxybenzamine inherently inhibits the contractile response of CCK-PZ and caerulein on esophagus and other smooth muscle.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.445-447
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• 2018

Leuconostoc lactis CCK940, which was isolated from kimchi obtained from a Korean traditional market, produced an oligosaccharide with a degree of polymerization of more than 4. In this study, the draft genome sequence of L. lactis CCK940 was reported by using PacBio 20 kb platform. The genome of this strain was sequenced and the genome assembly revealed 2 contigs. The genome was 1,741,511 base pairs in size with a G + C content of 43.33%, containing 1,698 coding sequences, 12 rRNA genes, and 68 tRNA genes. L. lactis CCK940 contained genes encoding glycosyltransferase, sucrose phosphorylase, maltose phosphorylase, and ${\beta}$-galactosidase which could synthesize oligosaccharide.