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Disinfection of Fusarium-infected Rice Seeds by Prochloraz and Gaseous Chlorine Dioxide

  • Jeon, Young-ah;Lee, Young-yi;Lee, Ho-sun;Sung, Jung-sook;Lee, Seokyoung
    • 한국균학회소식:학술대회논문집
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    • 2014.10a
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    • pp.25-25
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    • 2014
  • Three species of Fusarium, F. fujikuroi, F. verticillioides and F. proliferatum, are known to be associated with bakanae disease of rice [1, 2]. F. fujikuroi infects rice flowers and survive in endosperm and embryo of the seeds. Infected seed is an important source of primary inoculum of pathogens [3]. Seeds of rice (Oryza sativa cv. Boramchan) collected from bakanae-infected field were found to be 96% infected with Fusarium sp., 52% with F. fujikuroi, 42% with F. verticillioides, and 12% with F. proliferatum as determined by incubation method and species-specific PCR assays. F. fujikuroi was detected at lemma/palea, endosperm and embryo whereas F. verticillioides and F. proliferatum were recovered only from lemma/palea by means of component plating test. Seed disinfection methods have been developed to control bakanae disease and prochloraz has been most widely used for rice seeds. Two chemicals formulated with prochloraz (PC 1) and prochloraz + hexaconazole (PC 2) that inhibit biosynthesis of ergosterol strongly reduced the incidence of Fusarium spp. on selective media to 4.7% and 2.0%, respectively. Disease symptoms of rice seedlings in nursery soil were alleviated by chemical treatment; seedlings with elongated leaves or wide angle between leaf and stem were strikingly reduced from 15.6 to 3.2% (PC 1) and 0 (PC 2), stem rots were reduced from 56.9 to 26.2% (PC 1) and 32.1% (PC 2), and normal seedling increased from 0.4 to 13.3% (PC 2). Prochloraz has some disadvantages and risks such as the occurrence of tolerant pathogens [4] and effects on the sterol synthesis in animals and humans [5]. For these reasons, it is necessary to develop new disinfection method that do not induce fungal tolerance and are safe to humans and animals. Chlorine dioxide ($ClO_2$), that is less toxic, produces no harmful byproducts, and has high oxidizing power, has been reported to be effective at disinfection of several phytopathogenic fungi including Colletotrichum spp. and Alternaria spp. [6]. Gaseous $ClO_2$ applied to rice seeds at a concentration of 20 ppm strongly suppressed mycelial growth of Fusarium fujikuroi, F. verticillioides and F. proliferatum. The incidence of Fusarium spp. in dry seed with 8.7% seed moisture content (SMC) tended to decrease as the concentration of $ClO_2$ increased from 20 to 40 ppm. Applying 40 ppm $ClO_2$ at 90% relative humidity, incidence was reduced to 5.3% and resulted in significant reduction of disease symptoms on MS media. In nursery soil, stem rot was reduced from 56.9 to 15.4% and the number of normal seedlings increased from 0.4 to 25.5%. With water-soaked seeds (33.1% SMC) holding moisture in the endosperm and embryo, the effectiveness of disinfection using $ClO_2$ increased, even when treated with only 20 ppm for four hours. This suggests that moisture was a key element for action of $ClO_2$. Removal of the palea and lemma from seeds significantly decreased the incidence of Fusarium spp. to 3.0%. Seed germination appeared to decrease slightly by water-soaking at $30^{\circ}C$ because of increased SMC and by physical damage of embryos from hulling. These results indicate that the use of gaseous $ClO_2$ was effective as a means to disinfect rice seeds infected with Fusarium spp. and that moisture around the pathogens in the seed was an important factor for the action of $ClO_2$. Further investigations should be conducted to ascertain the best conditions for complete disinfection of Fusarium spp. that infect deep site of rice seeds.

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The Effective Resonance of Caves & Records of a Cave Concert (동굴의 자연음향 효과, 그리고 음악회장 운영사례)

  • Hyun, Haeng-Bok
    • Journal of the Speleological Society of Korea
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    • no.95
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    • pp.35-49
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    • 2009
  • Ever since the beginning of time, caves not only have offered a place to live for humans but they have also been used as cultural spaces. That is, in the event of making some sounds in a location within the cave, the sound that is created is greatly magnified and sounds out as if it is being amplified from a giant megaphone. This, as we well know it, is known as the resonance effect. Here, the cave itself appears to function as a massive wind instrument. Especially in cases like the Altamira Cave (Spain) where cave paintings were found, the point where the cave drawings were found has commonalities in that it is a wide space and that it is usually discovered together with flutes and drums that are made with mammoth bones. We need to focus on this point. We can infer from these facts that the prehistoric people have carried out cultural activities along with their incantation rituals within those caves. In the meantime, amongst the Korean traditional arts, in the case of pansori which is a representative vocal genre, there have been examples where caves were used as practicing locations for those people who are training to perfect their singing. This is known as toguldoggong(土窟獨功) which literally means 'obtaining one's own art by oneself in the earth cave by practicing incessantly'. This process along with pokpodoggong (瀑布獨功) (same as above except that the location is by the waterfall) is the final training stage in order to become a recognized virtuoso on the part of the apprentice. This could be compared to the final annealing and finishing process of producing a metalwork. This has been a long tradition followed by most Korean traditional artists in order to perfect their sound which is harmonious with nature within natural surroundings. By honing in on this point, I have come to think about this matter repeatedly while coaching the university students in vocal singing. In short, I came to the conclusion that "the making of natural sounds will be obtained naturally within natural surroundings like caves!" Consequently, The Society for Studying Cave Sounds was inaugurated on January 1992 along with some of my students. We made use of times like vacations to go around exploring caves all over Jeju and carried out investigations of sounds along with cave exploration on an experimental basis. After 5 years, in September of 1997, we were able to host the first ever cave concert domestically at the Whale Nostril Cave(東岸鯨窟) on Wu-do. After that, we have been hosting the cave concert once every year. We have achieved a record of a total of 14 cave concerts until 2009 of this year. Out of these, 2 were held in Seokhwaeam Cave in Kangwon Province, another two were held in Manjang Cave which is a lava cave, and the remaining 10 were held in the Whale Nostril Cave of Wu-do. Along with that, I have carried out a special recording for the production of a cave music CD in May of 1999. This paper was written and organized by using the main materials that were derived from the experiences of using caves as concert halls in the past. It is hoped that this cave concert will offer a very unique experience to tourists who come to Jeju every year and give them the best possible superior natural sound effect that only Jeju caves can offer.

Flora of Wonju-Hoengseong Area (원주.횡성 지역의 식물상)

  • Ko, Sung-Chul;Son, Dong-Chan;Kim, Hyun-Jong;Hwang, Hee-Suk;Shin, Young-Hwa
    • Korean Journal of Plant Resources
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    • v.22 no.5
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    • pp.365-380
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    • 2009
  • Flora of vascular plants in mountains located at Wonju-si and Hoengseong-gun areas such as Chiak-san(1,288m), Taegi-san(1,261.4m), Obong-san(1,126.2m), Eungbong-san(1,094.9m), Eodab-san(789.4m), Deokgo-san(521.2m), Deokga-san(700.5m) and Seongji-bong(791m) was investigated from April, 2008 to May, 2009, and results from the previous researches in which voucher specimens had been presented from Balgyo-san(998.4m), Oeum-san(930.4m), Baekun-san(1,037.1m) and Chiak-san(1,288m) were included in the list of vascular plants from these areas. This investigations resulted in 804 taxa consisted of 680 species, 1 subspecies, 111 varieties, and 12 forms of 383 genera under 97 families, and totally in 973 taxa (21.14% of all vascular plants in Korea) of 818 species, 1 subspecies, 138 varieties and 16 forms of 418 genera under 105 families on addition of voucher specimens in the previous researches. Forests of the investigated areas were generally mixed of Pinus densiflora and deciduous trees. The areas with comparatively excellent vegetation were valley from Guryong-sa (temple) to Biro-bong (summit) via Seryeom-pokpo (fall) in Mt. Chiak-san, and Keunseong-gol (valley) and eastern slope from Taegibungyo-teo to Naksu-dae (fall) in Mt. Taegi-san. 10 families with abundantly collected species were Compositae, Graminae, Rosaceae, Ranunculaceae, Leguminosae, Cyperaceae, Liliaceae, Saxifragaceae, Umbelliferae and Labiatae in order, and they occuied 49.12% of all collected taxa. Endemic plants found in these areas were 38 taxa including Hanabusaya asiatica, Megaleranthis saniculifolia, and Pyrus ussuriensis var. diamantica, and rare and endangered ones were 24 taxa including Hanabusaya asiatica, Viola websteri, Viola diamantica, and Patrina saniculaefolia. Specially designated plants by the Ministry of Environment were 88 taxa including 12 taxa of 5th degree such as Woodsia intermedia, Hanabusaya asiatica, Equisetum pratense, Iris koreana, Lilium cernum, Trillium tschonoskii, Magnolia kobus(cultivated), Gastrodia elata, Polypodium virginianum, Cimicifuga heracleifolia, Megaleranthis saniculifolia and Viola websteri. 47 taxa of alien plants were found. As to 609 taxa (13.23% of all vascular plants in Korea) of useful plants, 334 taxa for the edible, 269 taxa for the medicinal, 127 taxa for the ornamental, 332 taxa for the forage, 3 taxa for the industrial raw material, 31 taxa for the timber and 13 taxa for the fiber were classified, respectively.

Clinical characteristics of acute lower respiratory tract infections due to 13 respiratory viruses detected by multiplex PCR in children (소아에서 13종 호흡기 바이러스에 의한 급성 하기도 감염의 임상 양상)

  • Lim, Jeong-Sook;Woo, Sung-Il;Baek, Yun-Hee;Kwon, Hyuk-Il;Choi, Young-Ki;Hahn, Youn-Soo
    • Clinical and Experimental Pediatrics
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    • v.53 no.3
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    • pp.373-379
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    • 2010
  • Purpose : This study was performed to investigate the epidemiologic and clinical features of 13 respiratory viruses in children with acute lower respiratory tract infections (ALRIs). Methods : Nasopharyngeal aspirates were prospectively obtained from 325 children aged 15 years or less from May 2008 to April 2009 and were tested for the presence of 13 respiratory viruses by multiplex real-time-polymerase chain reaction (RT-PCR). Results : Viruses were identified in 270 children (83.1%). Co-infections with ${\geq}2$ viruses were observed in 71 patients (26.3 %). Respiratory syncytial virus (RSV) was the most common virus detected (33.2%), followed by human rhinovirus (hRV) (19.1%), influenza virus (Flu A) (16.9%), human metapneumovirus (hMPV) (15.4%), parainfluenza viruses (PIVs) (8.3%), human bocavirus (hBoV) (8.0%), adenovirus (ADV) (5.8%), and human coronavirus (hCoV) (2.2%). Clinical diagnoses of viral ALRIs were bronchiolitis (37.5%), pneumonia (34.5%), asthma exacerbation (20.9%), and croup (7.1%). Clinical diagnoses of viral bronchiolitis and pneumonia were frequently demonstrated in patients who tested positive for RSV, hRV, hMPV, or Flu A. Flu A and hRV were most commonly identified in children older than 3 years and were the 2 leading causes of asthma exacerbation. hRV C was detected in 14 (4.3%) children, who were significantly older than those infected with hRV A ($mean{\pm}SD$, $4.1{\pm}3.5$ years vs. $1.7{\pm}2.3$ years; P =0.009). hBoV was usually detected in young children ($2.3{\pm}3.4$ years) with bronchiolitis and pneumonia. Conclusion : This study described the features of ALRI associated with 13 respiratory viruses in Korean children. Additional investigations are required to define the roles of newly identified viruses in children with ALRIs.

Regulatory Characterization of xylA Promoter Region in Escherichia coli (대장균의 xylA 프로모터 영역의 조절 특성)

  • Kang, Byung-Tae;Roh, Dong-Hyun;Joo, Gil-Jae;Rhee, In-Koo
    • Applied Biological Chemistry
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    • v.39 no.6
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    • pp.443-448
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    • 1996
  • In order to investigate the function of xylA promoter(Pxyl) as regulatory region Pxyl-lacZ fusion gene was constructed by the insertion of xylA promoter to the multiple cloning site of upstream of lacZ gene in a multicopy numbered plasmid pMC1403 containing promoterless lac operon, which was designated pMCX191, and Pxyl-lacZ fragment from pMCX191 was inserted to low copy numbered plasmid pLG339, designated pLGX191. The expressions of ${\beta}-galactosidase$ in these recombinant plasmids containing Pxyl-lacZ fusion gene were induced strongly by the addition of xylose, repressed by the addition of 0.2% glucose in the presence of xylose. The catabolite repressions were derepressed by the addition of 1 mM cAMP as same as native xylA gene. The fragment of xylA promoter was partially deleted from the upstream of xylA promoter by exonuclease III to investigate the regulation site of xylA promoter and the degrees of deletion derivatives of xylA promoter were analyzed by the DNA base sequencing. By the investigations of the induction by xylose, repression by glucose and derepression by cAMP on xylose isomerase production, the regulation site of xylA promoter may be located in segment between -165 and -59 bp upstream from the initiation site of xylA translation.

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A Study on the Working Environment Recognition and the Caracter Disposition of Nurse Aides (간호조무사의 근무환경인식과 성격성향에 관한 연구)

  • Lee Sun Yi
    • Journal of Korean Public Health Nursing
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    • v.4 no.1
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    • pp.57-74
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    • 1990
  • As the whole world took on the tendency to be highly industrialized, it became necessary for each field of occupation to require professional man power. Especially, since the World War n, the participation of woman power in economic activities has been continually increasing. In our country also, because of the rapid economic growth, change in the way of thinking of women as well as their participation in economic activities are increasing. Thus, woman power is being utilized in various occupational fields from simple physical labor to those that require high-professional skill. Also, continued economic development policies, by setting the establishment of welfare society as the ideology to be fulfilled, brought expansion of medical facilities in the field of public health and increase in man power in that field. As for the nursing specialists, more than 6000 have been being produced per year and as of the end of 1988, the total number of nursing specialists, reached 123, 115. Therefore, this study is done to recognize the professional knowledge and ability of nursing specialists, who take up $40\%$ of the total public-health related man power in our country, through evaluating their working environment and their disposition of character. This study, which was done from September 18th to September 30th 1989, took on the method of using formed questionnaires that had been amended and supplemented during two preparatory investigations, 322 of such questionnaires were used as an analytical material. In the formation of questionnaires, 12 questions were related to the working environment, and 26 in fortotal were related to the disposition of character, 5 for wise-disposition, 11 for activedisposition and 10 for open-disposition. The measuring method, which used 5-point-standard, allowed 5 points for affirmative recognition of the working environment, also 5 points for showing wise, active and open disposition of character and only point in opposite cases. Collected materials were analyzed, through an electronic calculation, into the average value, the standard deflection percentage, pearson corelative number and stepwise multiple regression. Summarizing the results from this study is as follows: 1. It was shown that the nursing specialists with the average of 3.07 have affirmative recognition of their working environment. The questions which drew most affirmative reaction were those concerning finance-management system such as hand, the questions that received negative reaction were those concerning communication method with the average of 2.49. Such reaction seems to have resulted from the cramming regulation by the superior authorities. Concerning the recognition of working environment in relation to employment conditions, more affirmative recognition is shown with the average of 3.14. at hospitals where injection job is not performed. The nursing specialists working at regular hospitals show more affirmative recognition than those at general hospitals, the averages being respectiely 3.16 and 3.03. 2. As for the disposition of character of the nursing specialists, active-disposition was highest with the average of 3.38, next was wise-disposition with 3.20 and the lowest was open-diposition with 2.98. Variable-wise disposition of character shows that wise-disposition and academic background are beneficially correlated by 0.12. Ative-disposition and open-disposition show correlation to the office term by respectively 0.16 and 0.21. In other words. better academic background leads to higher wise-disposition and more - experience results in higher active and open disposition. Also, the class that performs the injection job, in relation to the working environment, might cause change in the self-conceit that identify those in that class with the nurses; however, as far as professional judgment and action, in dealing with nursing job, being wise, active and open is concerned, not much effect is made. 3. The relation between the recognition of the working environment and the disposition of character is that more afirmative recognition- a nursing specialist has about her working environment, the higher the active-disposition becomes by 0.13. The degrees of the relation between recongnition of environment and wise and open dispositions show respectively 0.06 and -0.06 and -0.06. That is to say that when having more affirmative recognition of the working environment, a nursing specialist shows wise but closed disposition of character. This, howerver, didn't mean much statistically. When observing the results mentioned above, it is conspicuous that the nursing specialists, working as substitutes for the nurse at medical institutions of various sizes, get the feeling of being somewhat equal to the nurses and to some extent, fulfill their desire to accomplish their ego; however, as far as professional ability expansion if concerned. they lack wise and open dispositions. Therefore, considiering upon the results of this study, in medical institutions where the work of nursing specialists is regaded equal to that of the nurses, as a medical member who deals with human lives, it is desirable to make the nursing specialists work under the supervision of the nurses and to offer them continuous education to strengthen and improve their natural dispositions.

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Recent Progress in Air Conditioning and Refrigeration Research - A Review of papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 1998 and 1999 - (공기조화, 냉동 분야의 최근 연구 동향 - 1998년 1999년 학회지 논문에 대한 종합적 고찰 -)

  • 이재헌;김광우;김병주;이재효;김우승;조형희;김민수
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.12
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    • pp.1098-1125
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    • 2000
  • A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 1998 and 1999 has been done. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environment. The conclusions are as follows. 1) A review of the recent studies on fluid flow, turbomachinery and pipe-network shows that many experimental investigations are conducted in applications of impingement jets. Researches on turbulent flows, pipe flows, pipe-networks are focused on analyses of practical systems and prediction of system performance. The results of noise reduction in the turbomachinery are also reported. 2) A review of the recent studies on heat transfer analysis and heat exchanger shows that there were many papers on the channel flow with the application to the design of heat exchanger in the heat transfer analysis. Various experimental and numerical papers on heat exchanger were also published, however, there were few papers available for the analysis of whole system including heat exchanger. 3) A review of the recent studies on heat pump system have focused on the multi-type system and the heat pump cycle to utilize treated sewage as the heat source. The defrosting and the frosting behaviors in the fin-tube heat exchanger is experimentally examined by several authors. Several papers on the ice storage cooling system are presented to show the dynamic simulation program and optimal operation conditions. The study on the micro heat pipes for the cooling of high power electronic components is carried out to examine the characteristics of heat and mass transfer processed. In addition to these, new type of separate thermosyphon is studied experimentally. 4) The recent studies on refrigeration/air conditioning system have focused on the system performance and efficiency for new alternative refrigerants. New systems operating with natural refrigerants are drawing lots of attention. In addition to these, evaporation and condensation heat transfer characteristics of traditional and new refrigerants are investigated for plain tubes and also for microfin tubes. Capillary tubes and orifice are main topics of research as expansion devices and studies on thermophysical properties of new refrigerants and refrigerant/oil mixtures are widely carried out. 5) A review of the recent studies on absorption cooling system shows that numerous experimental and analytical studies on the improvement of absorber performance have been presented. Dynamic analysis of compressor have been performed to understand its vibration characteristics. However research works on tow-phase flow and heat transfer, which could be encountered in the refrigeration system and various phase-change heat exchanger, were seemed to be insufficient. 6) A review of recent studies on duct system shows that the methods for circuit analysis, and flow balancing have been presented. Researches on ventilation are focused on the measurement of ventilation efficiency, and variation of ventilation efficiency with ventilation methods by numerous experimental and numerical studies. Furthermore, many studies have been conducted in real building in order to estimate indoor thermal environments. Many research works to get some information for cooling tower design have been performed but are insufficient. 7) A review on the recent studies on architectural thermal environment and building mechanical systems design shows that thermal comfort analysis is sitting environment, thermal performance analysis of Korean traditional building structures., and evaluation of building environmental load have been performed. However research works to improve the performance of mechanical system design and construction technology were seemed to be insufficient.

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p53 Expression Patterns in Non-small Cell Lung Cancers (비소세포 폐암에서의 p53 단백의 발현 양상)

  • Kim, Sun-Young;Hong, Seok-Cheol;Han, Pyo-Seong;Lee, Jong-Jin;Cho, Hai-Jeong;Kim, Ae-Kyoung;Kim, Ju-Ock;Lee, Sang-Sook
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.6
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    • pp.659-668
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    • 1993
  • Background: p53 is currently considered as a tumor suppressive gene product, and its alterations are suggested to be involved in several human malignancies, including non-small cell lung cancers. p53 expression rates are variable in many reports and among cell types. Also, whether the phase of p53 expression is early or late during carcinogenesis is not certain. Thus, We have investigated to evaluate p53 expression rates of the various cell types and tissues and identify expression phase (early or late). Method: We obtained 71 tissue from 50 non-small cell lung cancer patients and performed the simple immunohistochemical staining using nonspecific monoclonal antibody(NCL-p53DO7). Results: 1) In non-small cell lung cancer patients. the expression rate of lungs(46.5%) is higher than that(25.0%) of lymph nodes. But, there is no significant difference between two groups. 2) Among the various cell types, p53 expression rates in squamous cell carcinoma and adenocarcinoma are 58.3% and 50.0% respectively without significant difference. 3) p53 expression rates in various stages are 33.3%, 60.0%, 40.0%, 60.0% and 66.7% in stage I, II, IIIa, IIIb and IV, respectively with no significant difference. 4) p53 expression rates in the various T parameters are 33.3%, 50.0%, 16.7% and 100% in T1, T2, T3 and T4, respectively and p53 expression rates in the various N parameters are 27.3%, 22.2% and 25.0% in N1, N2 and N3, respectively. There are no significant differences in the expression rates among varous T & N parameters. 5) p53 expression rates of lymph nodes in patients who have positive stains in lungs are 12.5% and 50.0% in N1 and N2. 6) p53 expression rates of all lymph nodes in patients who have negative stains in lungs are 0.0%. Conclusion: The above results show that p53 expression rate in non-small cell lung cancers is not correlated with cell type and progression of stage and it is thought to need further investigations about at what phase p53 expression influences the development and progression of lung cancers.

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The Effect of Exercise on Pulmonary Function (운동이 폐기능에 미치는 영향)

  • Park, Jae-Seuk;Kim, Youn-Seup;Choi, Eun-Kyoung;Jee, Young-Koo;Lee, Kye-Young;Kim, Keun-Youl;Chun, Yong
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.2
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    • pp.351-359
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    • 1998
  • Background: The effects of exercise on pulmonary function are complex and have been the subject of many investigations. But, there has been disputes about the effect of exercise on spirometric parameters and there is no study about the effect of exercise on IOS(Impulse Oscillometry)parameters. IOS, a new method of pulmonary function test, is based on the relationship between the pressure and flow oscillation which is produced by applying sinusoidal pressure oscillation to the respiratory system via the mouth. Method: Fifty-nine young adults without respiratory symptoms were divided into three groups according to degree of exercise(hard exercise group: mean exercise time is over three hours per week at least for the last one month, light exercise group : between thirty minutes to three hours, nonexercise group : less than thirty minutes) and undertaken pulmonary function test(simple spirometry and IOS). Results: The effects of exercise on spirometric parameters; percentage of predictive value of forced vital capacity(FVC % pred) was higher in hard exercise group than nonexercise group(hard exercise group: $102.4{\pm}14.8$, nonexercise group: $93.7{\pm}9.9$, p=0.017), but there was no significant difference in percentage of predicted value of forced expiratory volume in one second(FEV 1 % pred) and percentage of predicted value of forced expiratory flow 50% (FEF 50% pred) between groups. The effects of exercise on IOS parameters: Reactance at 5Hz(X5) was significantly lower in hard exercise group than nonexercise group(hard exercise group: $-0.166{\pm}0.123hPa/1/s$, nonexercise group: $-0.093{\pm}0.036hPa/1/s$, p=0.006) but there was no significant difference in central resistance(Rc), peripheral resistance(Rp), resonance frequency(RF) and resistance at 5Hz, 20Hz between groups. Conclusion: Hard exercise increased FVC % pred on spirometric parameters and decreased reactance at 5Hz(X5) on IOS parameters.

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Evaluation of Autonomic Neuropathy in Patients with Sleep Apnea Syndrome (수면 무호흡 증후군 환자에서 자율 신경 장애의 평가)

  • Lee, Hak-Jun;Park, Hye-Jung;Shin, Chang-Jin;Kim, Ki-Beom;Chung, Jin-Hong;Lee, Kwan-Ho;Lee, Hyun-Woo
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.2
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    • pp.404-415
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    • 1998
  • Background: Sleep apnea syndrome, which occurs in 1~4 % of the adult population, frequently has different cardiovascular complications such as hypertension, ischemic heart disease, cardiac arrythmia as well as sleep-wake disorder such as excessive daytime hypersomnolence or insomnia. Mortality and vascular morbidity are reported to be significantly higher in sleep apnea syndrome patients than in normal population. According to the recent studies, autonomic dysfunction as well as hypoxemia, hypercapneic acidosis, and increased respiratory effort, may playa role in the high prevalence of cardiovascular complications in patients with sleep apnea syndrome. However the cause and mechanism of autonomic neuropathy in patients with sleep apnea syndrome are not well understood. We studied the existence of autonomic neuropathy in patients with sleep apnea syndrome and factors which influence the pathogenesis of autonomic neuropathy. Method: We used the cardiovascular autonomic neuropathy(CAN) test as a method for evaluation of autonomic neuropathy. The subjects of this study were 20 patients who diagnosed sleep apnea syndrome by polysomnography and 15 persons who were normal by polysomnography. Results: Body mass index and resting systolic blood pressure were higher in sleep apnea group than control group. Apnea index(Al), respiratory disturbance index(RDI) and snoring time percentage were significantly higher in sleep apnea group compared with control group. But there were no significant differences in saturation of oxygen and sleep efficiency in two groups. In the cardiac autonomic neuropathy test, the valsalva ratio was significantly low in sleep apnea group compared with control group but other tests had no differences between two groups. The CAN scores and corrected QT(QTc) interval were calculated significantly higher in sleep apnea group, but there were no significant correlations between CAN scores and QTc interval. There were no significant data of polysomnography to correlate to the CAN score. It meant that the autonomic neuropathy in patients with sleep apnea was affected by other multiple factors. Conclusion: The cardiovascular autonomic neuropathy test was a useful method for the evaluation of autonomic neuropathy in patients with sleep apnea syndrome and abnormalities of cardiovascular autonomic neuropathy were observed in patients with sleep apnea syndrome. However, we failed to define the factors that influence the pathogenesis of autonomic neuropathy of sleep apnea syndrome. This study warrants futher investigations in order to define the pathogenesis of autonomic neuropathy in patients with sleep apnea syndrome.

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