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Temporal and Spatial Characteristics of Surface Winds over the Adjacent Seas of the Korean Peninsula (한국 주변해역에서의 해상풍의 시공간적 특성)

  • Han, Sang-Kyu;Lee, Heung-Jae;Na, Jung-Yul
    • 한국해양학회지
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    • v.30 no.6
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    • pp.550-564
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    • 1995
  • The temporal and spatial characteristics of wind fields over the neighbouring seas of the Korean peninsula are investigated using 10-years daily wind data during 1978${\sim}$1987 which have been spatially smoothed and low-pass filtered. Long term annual and monthly means are examined for synoptic patterns and spectral analyses are made for temporal variability and spatial coherence. Spatial patterns of the annual mean wind stress and curl have a strong resemblance with those of monthly means during the winter season. Two outstanding periodicities are observed at 1 and 2 cycles per year. The synoptic winds over the study area are highly coherent at both the annual and semi-annual periodicities. However, each basin has its own characteristic spatial pattern. For instance, the prevailing wind during the winter season is northerIy over the northern East Sea (ES), Yellow Sea (YS), and northern East China Sea (ECS), while it is northwesterly over the southern ES and northesterly over the northern ES and southern ECS. At the same time, the wind stress curl is positive over the northern ES and southern ECS, while it is negative over the southern ES, YS and northern ECS. On the other hand, the wind field during the summer season, with its strength being much reduced, is completely different from that during the winter season, and frequent passage of tropical storms provokes large temporal variability over ECS. One remarkable point is that the annual cycle, dominated by the Siberian High, tends to propagate from northeast to southwest, i.e., from northern 25 toward southern ES, YS and ECS, while the semi-annual cycle propagates in the opposite direction, from southwest to northeast. The semi-annual periodicity may reflect development of extratropical cyclones in spring and fall which frequently cross the Korean peninsula. In higher frequencies, there are no dominant periodicities, but local winds over YS and ES are highly correlated for frequencies larger than 0.1 cycles per day and phase difference increases linearly with frequency. This linear increase of phase corresponds to phase speed of 550 and 730 km/d at 0.1 and 0.3 cpd, respectively, The phase speed is apparently coincident with moving speed of extratropical cyclones across the Korean peninsula in the west-east direction.

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Surgical Outcome of Tetralogy of Fallot in Adolt -Implication of Preoperative Cyanosis- (수술 전 청색증 정도에 따른 성인 활로씨 4징증의 임상 양상)

  • Kim Sang-hwa;Park Soon-Ik;Park Jung-Jun;Song Hyun;Lee Jae-Won;Seo Dong-Man;Song Meong-Gun;Song Jong-Min;Kang Duck-Hyun;Song Jae-Kwan;Jang Wan-Sook;Kim Young-Hwue;Yun Tae-Jin
    • Journal of Chest Surgery
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    • v.38 no.4 s.249
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    • pp.271-276
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    • 2005
  • We analysed differences in operative methods and postoperative outcome according to the severity of preoperative cyanosis in adult ToF (Tetralogy of Fallot) patients. Material and Method: From August 1989 to June 2001, thirty three adult patients, 18 females and 15 males, underwent total correction for ToF. Their age ranged from 15 years to 54 years (median: 34). Patients were divided into 2 groups by preoperative $SaO_2$ (arterial oxygen saturation): group I$(n=cyanotic,\;SaO_2\;\geq94\%)$ and group II $(acyanotic,\; SaO_2\geq95%)$. Preoperative median hemoglobin level was higher in group I compared to group II (17.5 g/dl vs 15 g/dl). Postoperative follow-up duration ranged from 1 to 94 months (670 patient-month, median: 14 months), and 63 two-dimensional echocardiographic examinations were done during this period. Result: There were no early or late mortality. With regard to RVOT (right ventricular outflow tract) reconstruction, trans-annular patch and RV-PA extracardiac conduit were used in 7 and 3 patients respectively, and all of them belonged to group I. In group I, cardiopulmonary bypass time, aortic cross-clamping time, ICU day, hospital day were significantly longer than in group II, and postoperative inotropic support was significantly greater than in group II. There was no ventricular arrhythmia in both groups, and one patient in group I suffered from atrial arrhythmia, which was resolved spontaneously after tricuspid and pulmonary valve replacement. During follow-up periods, functional class, residual RVOT stenosis and pulmonary regurgitation, tricuspid regurgitation, occurrence of ventricular and atrial arrhythmias were comparable between two groups. Conclusion: In adult ToF patients with severe preoperative cyanosis, more aggressive RVOT reconstruction and careful postoperative care are mandatory. However intermediate-term outcome of this group of patients is comparable to the patients with minimal or no preoperative cyanosis.

Comparison of Mitral Valve Repair between a Minimally Invasive Approach and a Conventional Sternotomy Approach (승모판 성형술에 있어 최초 침습적 수술방식과 고전적 정중 흉골 절개술을 통한 접근방식의 비교)

  • Cho, Won-Chul;Je, Hyoung-Gon;Kim, Jeong-Won;Lee, Jae-Won
    • Journal of Chest Surgery
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    • v.40 no.12
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    • pp.825-830
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    • 2007
  • Background: Minimally invasive cardiac surgery appears to offer certain advantages such as earlier postoperative recovery and a greater cosmetic effect than that achieved through conventional sternotomy. However, this approach has not yet been widely adopted in Korea to replace complex open heart surgery such as mitral valve reconstruction. This study compared the results of robot assisted minimally invasive mitral valve repair with those results of conventional sternotomy. Material and Method: From December 1993 to December 2005, 520 consecutive patients underwent mitral valve reconstruction for mitral regurgitation in our institution. These patients were subdivided according to those whose surgery used the conventional sternotomy approach (Group S, n=432) and those who underwent minimally invasive right anterior thoracotomy (Group M, n=88); we then compared the clinical results of both groups. When we performed minimally invasive right thoracotomy, we used a robot (AESOP 3000) and made an incision less than 5 cm. Result: Our study patients in both groups were similar for their age, gender and preoperative ejection fraction. There were two hospital mortalities in group S. but there was no mortality in the group M patients. Significant reductions in the ICU stay and the postoperative hospital stay were observed in the group M patients compared with the group S patients. However, both the bypass time and the aortic cross-clamp time were significantly longer in the group M patients. In spite of the confined incision in the group M patients, there were no limitations on the mitral valve repair techniques. There was a similar frequency of postoperative significant residual mitral regurgitation in both groups. Conclusion: In this study, the minimally invasive mitral valve repair showed comparable early results with the conventional sternotomy patients. We will now need long-term follow-up of these patients who underwent minimally invasive mitral valve repair, but we anticipate that based on the results of this study, we will begin to routinely perform minimally invasive cardiac surgery as out primary approach for mitral valve reconstruction.

DRAG EFFECT OF KOMPSAT-1 DURING STRONG SOLAR AND GEOMAGNETIC ACTIVITY (강한 태양 및 지자기 활동 기간 중에 아리랑 위성 1호(KOMPSAT-1)의 궤도 변화)

  • Park, J.;Moon, Y.J.;Kim, K.H.;Cho, K.S.;Kim, H.D.;Kim, Y.H.;Park, Y.D.;Yi, Y.
    • Journal of Astronomy and Space Sciences
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    • v.24 no.2
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    • pp.125-134
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    • 2007
  • In this paper, we analyze the orbital variation of the Korea Multi-Purpose SATellite-1(KOMPSAT-1) in a strong space environment due to satellite drag by solar and geomagnetic activities. The satellite drag usually occurs slowly, but becomes serious satellite drag when the space environment suddenly changes via strong solar activity like a big flare eruption or coronal mass ejections(CMEs). Especially, KOMPSAT-1 as a low earth orbit satellite has a distinct increase of the drag acceleration by the variations of atmospheric friction. We consider factors of solar activity to have serious effects on the satellite drag from two points of view. One is an effect of high energy radiation when the flare occurs in the Sun. This radiation heats and expands the upper atmosphere of the Earth as the number of neutral particles is suddenly increased. The other is an effect of Joule and precipitating particle heating caused by current of plasma and precipitation of particles during geomagnetic storms by CMEs. It also affects the density of neutral particles by heating the upper atmo-sphere. We investigate the satellite drag acceleration associated with the two factors for five events selected based on solar and geomagnetic data from 2001 to 2002. The major results can be summarized as follows. First, the drag acceleration started to increase with solar EUV radiation with the best cross-correlation (r = 0.92) for 1 day delayed F10.7. Second, the drag acceleration and Dst index have similar patterns when the geomagnetic storm is dominant and the drag acceleration abruptly increases during the strong geomagnetic storm. Third, the background variation of the drag accelerations is governed by the solar radiation, while their short term (less than a day) variations is governed by geomagnetic storms.

Molecular Diagnosis of Streptococcus pneumoniae in Middle Ear Fluids from Children with Otitis Media with Effusion (삼출성 중이염 소아의 중이액에서 폐구균의 분자적 진단)

  • Byun, Sung Wan;Kim, Han Wool;Yoon, Seo Hee;Park, In Ho;Kim, Kyung-Hyo
    • Pediatric Infection and Vaccine
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    • v.22 no.2
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    • pp.106-112
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    • 2015
  • Purpose: The long-term administration of antibiotics interferes with bacterial culture in the middle ear fluids (MEFs) of young children with otitis media with effusion (OME). The purpose of this study is to determine whether molecular diagnostics can be used for rapid and direct detection of the bacterial pathogen in culture-negative MEFs. Methods: The specificity and sensitivity of both polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) to the lytA gene of Streptococcus pneumoniae were comparatively tested and then applied for pneumococcal detection in the clinical MEFs. Results: The detection limit of the PCR assay was approximately $10^4$ colony forming units (CFU), whereas that of LAMP was less than 10 CFU for the detection of S. pneumoniae. Both PCR and LAMP did not amplify nucleic acid at over $10^6$ CFU of H. influenzae or M. catarrhalis, both of which were irrelevant bacterial species. Of 22 culture-negative MEFs from children with OME, LAMP positivity was found in twelve MEFs (54.5%, 12/22), only three of which were PCR-positive (25%, 3/12). Our results showed that the ability of LAMP to detect pneumococcal DNA is over four times higher than that of PCR (P<0.01). Conclusions: As a high-resolution tool able to detect nucleic acid levels equivalent to <10 CFU of S. pneumoniae in MEFs without any cross-reaction with other pathogens, lytA -specific LAMP may be applied for diagnosing pneumococcus infection in OME as well as evaluating the impact of a pneumococcal conjugate vaccine against OME.

Coronary Artery Bypass Graft Surgery in the Elderly (고령환자의 관상동맥 우회로 조성술)

  • 김학제;황재준;김현구;신재승;손영상;최영호
    • Journal of Chest Surgery
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    • v.32 no.8
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    • pp.715-721
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    • 1999
  • Background:The number of old patients receiving coronary artery bypass grafting(CABG) is increasing. With the more recent advances in operative techniques, the age at which CABG is indicated has also increased. This study evaluated the risk factors associated with the hospital mortality and the morbidity following CABG in elderly patients. Material and Method: Between March 1991 and June 1998, we retrospectively reviewed 45 consecutive patients aged 65 years or older who underwent CABG. We compared the data with the results of 179 patients under the age 65 years operated during the same period. Result: Mean age was 68${\pm}$1.41 years(range 65 to 74 years). Emergency surgery was required in 4, and elective surgery in 41 patients. The mean number of distal anastomosis per patient was 3.62 ${\pm}$0.81 and mean aortic cross-cramp time was 69.84${\pm}$18.5 minutes. Thirty patients had Canadian class III or IV preoperatively, but 43 patients had class I or II postoperatively. The left ventricular ejection fraction increased significantly from 54.23${\pm}$10.62% preoperatively to 58.14${\pm}$9.88% postoperatively(p<0.05). Postoperative complication was pneumonia in 2 patients, acute renal failure in 2 patients, sternal wound infection in 1 patient, and postoperative myocardial infarction in 1 patient. There were two postoperative deaths. The causes of deaths were low output syndrome in one patient, and sepsis due to pneumonia in the other patient. The hospital mortality was higher in the elderly group(4.4 versus 2.86%) but was not statistically significant(p>0.05). Incremental risk factors for hospital deaths in the elderly were emergent operation, preoperative PTCA, postoperative use of IABP and postoperative ARF(p<0.05). The duration of hospital stay after operation was significantly longer for the elderly group than the younger group(19.27${\pm}$12.51 vs 15.55${\pm}$6.99 days; p< 0.05). Follow-up was complete for 34 of the hospital survivors and ranged from 1 to 73 months(mean: 23.58${\pm}$19.56 months). There was no late mortality of cardiac origin. Conclusion: Age is an important factor in selecting optimal management for elderly patients with coronary compromise, but age alone should not dictate the choice of therapy. Coronary artery bypass surgery in the elderly is associated with acceptable early mortality and excellent long-term results.

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The Results of using the Cabrol Technique for Aortic Root Replacement (대동맥 근부치환술에 대한 Cabrol 술식의 성적)

  • Kim, Jeong-Won;Lee, Jong-Tae;Cho, Joon-Yong;Kim, Kyu-Tae;Kim, Gun-Jik
    • Journal of Chest Surgery
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    • v.41 no.5
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    • pp.573-579
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    • 2008
  • Background: Composite valve graft replacement is currently the treatment of choice for a wide variety of the lesions of aortic root disease. The purpose of this study was to explore the results of aortic root replacement after using the Cabrol technique over a 13-year period at our institution, and we analyzed the results to help surgeons make better decisions when repairing aortic root disease. Material and Method: Between January 1994 and December 2006, twenty-five patients underwent a Cabrol technique operation at our institution. The mean patient age was $43.7{\pm}14.1$ years old (range: $6{\sim}65$ years) and the male and female ratio was 21:4 (84% : 16%). The patients' follow-up was 100% complete, and the mean follow-up period was $60.7{\pm}50.4$ (range:$1{\sim}162$) months. Annuloaortic ectasia (n=18) was the most frequent cause of aortic disease in this series, followed by aortic dissection (n=7). The mean cardiopulmonary bypass time was $177.2{\pm}44.9$ minutes and the mean aortic cross clamping time was $123.4{\pm}34.1$ minutes. Nine patients were checked with MDCT (Multidetector computed tomography) for evaluating a well functioning secondary graft and the coronary anastomosis site. Result: The early mortality rate was 4% (1 of 25 patients). A significant stenosis, kinking or occlusion of the secondary graft was detected by MDCT in 4 patients. The overall survival rate was 88%. Conclusion: The Cabrol technique demonstrated a significant incidence of long-term complications such as secondary graft stenosis or obstruction. It could be used when the modified Bentall technique is not feasible.

Serum ghrelin and leptin concentrations in children with cancer : comparisons with normal children (소아 종양 환아의 혈중 Ghrelin과 Leptin의 농도: 정상 소아와 비교)

  • Park, So Hyun;Jung, Min Ho;Chung, Nac Gyun;Suh, Byung-Kyu;Lee, Byung Churl
    • Clinical and Experimental Pediatrics
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    • v.50 no.9
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    • pp.905-911
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    • 2007
  • Purpose : Ghrelin, being secreted from the stomach, stimulates growth hormone secretion and controls energy homeostasis by increasing appetite. Leptin, being secreted from the adipocytes, controls weight and energy homeostasis by decreasing appetite. Leptin concentration is reported to increase after childhood cancer therapy. This study was aimed to compare ghrelin and leptin concentrations in normal children and children who received cancer therapy. Methods : We enrolled forty-three patients who were diagnosed with cancer and received radiotherapy or chemotherapy during Dec. 2004 through Dec. 2005 in St. Marys hospital and Kangnam St. Marys hospital. Forty-five healthy children were selected as a control group whose age, gender, weight and height were similar to those of cancer group. The serum leptin and ghrelin concentrations were also measured by radioimmunoassay. Results : The cancer group showed higher BMI and leptin concentrations. The control group showed higher concentrations of ghrelin. Both control and cancer groups revealed positive correlations between leptin concentrations and BMI. Ghrelin concentrations in the control group showed negative correlations with age, height, weight and BMI but no significant correlation was found in the cancer group. All the parameters in the group treated with chemotherapy only were not different from those in the group treated with chemotherapy and irradiation. But the level of ghrelin in the acute myeloid leukemia group was much higher than those in the acute lymphoblastic leukemia group. Conclusion : Patients with pediatric cancer treatment have presented higher BMI and leptin concentrations but lower ghrelin concentrations than those in healthy children. Because of the relatively short duration and cross sectional method of the study, however, further long term and prospective study will be required in the future.

A Study on the Problem and Improvement of CRM in Financial Institutions (금융기관의 CRM문제점과 개선방안에 관한연구)

  • Lee, Sang-Youn;Oh, Sung-Taek;Kim, Moon-Jung
    • The Journal of Industrial Distribution & Business
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    • v.1 no.1
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    • pp.33-41
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    • 2010
  • In the age of globalization, effective and efficient corporate management is becoming more important as domestic and international business circumstances changes. In the middle of endless changes in business circumstances, fast reaction to customers and market, and offering customized goods and service became essential. In this respect, CRM designed to utilize customer information scientifically and systematically, has become an essential system and marketing strategy to enhance corporate competitiveness. CRM has placed the importance of customers in the front of marketing and has focused every process and business minds on customers. Recent change in the market and the trend of establishing and introducing CRM system has lead us to concentrate on the introduction of CRM in the financial institutions. This study searched for several views about CRM in academic and industrial papers. Through theoretical approach on CRM, the background of the introduction of CRM, the purpose of CRM, the characteristic and application of CRM, and the expected effect of CRM will be discussed. This study is focused on financial institutions where CRM is widely used. And through documents about examples of the introduction of CRM, the status of the establishment of domestic CRM and the necessity and trend of CRM will be discussed. Also the problem of CRM in the financial institutions and the improvement of CRM in domestic banks will be analyzed. When discussing CRM in the financial area, customers are the main source of corporate profit and through relationship management with the customers enhancing loyalty and maximizing profit can be obtained. Especially in CRM in financial institutions, maintaining existing customers makes higher profit ratio, so repurchasing and cross selling becomes important for obtaining lifetime value of existing customers who contribute to most of the profit of corporations. As a result, CRM should be completely customer oriented. CRM in financial institutions is not merely marketing work, but organizational competence which is made up of standardized work process through total process integration inside the corporation. Corporations which plan to introduce CRM should analyze the characteristics and conditions of corporations and establish purpose and strategy of CRM. And they need long term view to find out the factors which best fit for the introduction of CRM. To enable this, strategy composed of daily marketing activity and CRM concept is necessary. Also continued improvement through drill and training for operating organization should be followed to maintain CRM well. And corporate culture must settle customer as the center of corporate value. The race for introducing and improving CRM has already begun. CRM should not be regarded as a choice. It should be accepted as something essential. In this reality financial institutions should solve subdivision problem of customers and necessity of customers with the mind of 'customer's profit is my profit'. Customer focused management should not be emphasized only by words. Efforts like viewing from the customer's point must be nurtured to provide methods to help customers. That is, we should not just follow what is done in foreign countries. We should solve the problem of our customers according to the situation of our country, our industry, our corporation. Then we can gain the trust of customers, and the value derived from the customers will become the background of CRM which will lead the corporation to success.

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Effect of Acupuncture on Nasal Obstruction in Patients with Persistent Allergic Rhinitis: A Randomized Controlled Trial (지속성 알레르기비염의 비폐색에 대한 침치료의 효과: 무작위배정 대조군 연구)

  • Jo, Jeong-Hyo;Hong, Kweon-Eey;Kang, Wee-Chang;Choi, Sun-Mi;Park, Yang-Chun
    • Journal of Acupuncture Research
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    • v.22 no.6
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    • pp.229-239
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    • 2005
  • Objectives : Allergic rhinitis is a prevalent disease. Nasal obstruction is one of the main symptom in allergic rhinitis. It induces sleep disturbances, depression, attention deficit, memory impairments. Acupuncture treatment for rhinitis was mentioned in literature, but there is not enough report that provide evidence by well designed clinical study. The purpose of this research is to examine the effect of acupuncture treatment for nasal obstruction of allergic rhinitis. Methods : In this randomized, single blind, placebo-controlled study, we compared active acupuncture with minimal acupuncture for the treatment of nasal obstruction owing to persistent allergic rhinitis. Acupoints used in active acupuncture group were I120($Y{\hat{o}}nghyang$), GV23($Sangs{\hat{o}}ng$), IL4(Hapkok). Volunteers who satisfied the requirements were enrolled in study. Total nasal volume(NV) and total nasal minimum cross-sectional area(MCA) were measured by acoustic rhinometry before and after treatments(0min, 7.5min, 15min). Results : 101 subjects finished study. There were not difference between two groups on age, sex, weight, height, blood pressure, pulse, respiratory rate, severity of persistent allergic rhinitis, number of positive antigen. After treatment(0min) total NV were significantly increased compared with before treatment in active acupuncture group(p=0.0007) and minimal acupuncture group(p=0.0175). After treatment(15min) total NV of minimal acupuncture group was decreased compared with before treatment(p=0.2560), but total NV of active acupuncture group was maintained increasing in degree of borderline significance(p=0.0871). After treatment(0min) total NV were significantly increased compared with before treatment in active acupuncture group(0.0007) and minimal acupuncture group(p=0.0175). After treatment(Omin) total MCA were significantly increased compared with before treatment in active acupuncture group(p<0.000l) and minimal acupuncture group(p=0.0005). After treatment(15min) total MCA of minimal acupuncture group was decreased compared with before treatment(p=0.6082), but total NV of active acupuncture group was maintained increasing in degree of borderline significance(p=0.0929). Conclusion : Acupuncture treatment reduced nasal obstruction in persistent allergic rhinitis. Further study in the form of long term is needed.

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