• 제목/요약/키워드: GAS5

검색결과 10,101건 처리시간 0.043초

Environmental Pollution in Korea and Its Control (우리나라의 환경오염 현황과 그 대책)

  • 윤명조
    • Proceedings of the KOR-BRONCHOESO Conference
    • /
    • 대한기관식도과학회 1972년도 춘계종합 학술대회 초록집
    • /
    • pp.5-6
    • /
    • 1972
  • Noise and air pollution, which accompany the development of industry and the increase of population, contribute to the deterioration of urban environment. The air pollution level of Seoul has gradually increased and the city residents are suffering from a high pollution of noise. If no measures were taken against pollution, the amount of emission of pollutant into air would be 36.7 thousand tons per year per square kilometer in 1975, three times more than that of 1970, and it would be the same level as that of United States in 1968. The main sources of air pollution in Seoul are the exhaust has from vehicles and the combustion of bunker-C oil for heating purpose. Thus, it is urgent that an exhaust gas cleaner should be instaled to every car and the fuel substituted by less sulfur-contained-oil to prevent the pollution. Transportation noise (vehicular noise and train noise) is the main component of urban noise problem. The average noise level in downtown area is about 75㏈ with maximum of 85㏈ and the vehicular homing was checked 100㏈ up and down. Therefore, the reduction of the number of bus-stop the strict regulation of homing in downtown area and a better maintenance of car should be an effective measures against noise pollution in urban areas. Within the distance of 200 metres from railroad, the train noise exceeds the limit specified by the pollution control law in Korea. Especially, the level of noise and steam-whistle of train as measured by the ISO evaluation can adversely affect the community activities of residents. To prevent environmental destruction, many developed countries have taken more positive action against worsening pollution and such an action is now urgently required in this country.

  • PDF

Translocation of Tolclofos-methyl from Ginseng Cultivated Soil to Ginseng (Panax ginseng C. A. Meyer) and Residue Analysis of Various Pesticides in Ginseng and Soil (토양 중 잔류된 Tolclofos-methyl의 인삼(Panax ginseng C. A. Meyer)에 대한 이행 및 잔류 특성)

  • Kim, Ji Yoon;Kim, Hea Na;Saravanan, Manoharan;Heo, Seong Jin;Jeong, Haet Nim;Kim, Jang Eok;Kim, Kwan Rae;Hur, Jang Hyun
    • The Korean Journal of Pesticide Science
    • /
    • 제18권3호
    • /
    • pp.130-140
    • /
    • 2014
  • Recently, some of the previous studies reported that tolclofos-methyl is still exist in ginseng cultivated soil, even though it is has been banned for ginseng. Therefore, the current study was aimed to examine the levels of absorption and translocation of tolclofos-methyl from ginseng cultivated soil to ginseng root and leaf stem for the period of 1 year. For this study, ginseng plants were transplanted in pots and treated with $5.0mg\;kg^{-1}$ of tolclofos-methyl (50% WP). At the end of each interval periods (every three months) the samples (soil, roots and leaf stems) were collected and analyzed the absorption and translocation levels of tolclofos-methyl using gas chromatography and mass spectrometry (GC-MS). The limit of quantitation of tolclofos-methyl was found to be $0.02mg\;kg^{-1}$ and 70.0~120.0% recovery was obtained with coefficient of variation of less than 10% regardless of sample types. In this study, a considerable amount of translocation of tolclofos-methyl residues were found in soil (4.28 to $0.06mg\;kg^{-1}$), root (7.09 to $1.54mg\;kg^{-1}$) and leaf stem (0.79 to $0.69mg\;kg^{-1}$). The results show that the tolclofos-methyl was absorbted and translocated from ginseng cultivated soil to ginseng root and ginseng leaf stem and found to be decreased time-coursely. Secondly, we were also analyzed soil, root and leaf stems samples from Hongcheon, Cheorwon, Punggi and Geumsan by GC-MS/MS (172 pesticides), LC-MS/MS (74 pesticides). In this study, 43 different pesticides were detected ($0.01{\sim}7.56mg\;kg^{-1}$) in soil, root and leaf stem. Further, tolclofos-methyl was detected 4 times separately in root sample alone which is less ($0.01{\sim}0.05mg\;kg^{-1}$) than their maximum residual limit (MRL) in ginseng. Consequently, the results from both studies indicate the residues of tolclofos-methyl found in ginseng cultivated soil and ginseng ensuring their safety level. Moreover, long-term evaluations are needed in order to protect the soil as well as ginseng free from tolclofos-methyl residues.

The Effect and Safety of Alveolar Recruitment Maneuver using Pressure-Controlled Ventilation in Acute Lung Injury and Acute Respiratory Distress Syndrome (급성폐손상과 급성호흡곤란증후군 환자에서 압력조절환기법을 이용한 폐포모집술의 효과와 안정성)

  • Chung, Kyung Soo;Park, Byung Hoon;Shin, Sang Yun;Jeon, Han Ho;Park, Seon Cheol;Kang, Shin Myung;Park, Moo Suk;Han, Chang Hoon;Kim, Chong Ju;Lee, Sun Min;Kim, Se Kyu;Chang, Joon;Kim, Sung Kyu;Kim, Young Sam
    • Tuberculosis and Respiratory Diseases
    • /
    • 제63권5호
    • /
    • pp.423-429
    • /
    • 2007
  • Background: Alveolar recruitment (RM) is one of the primary goals of respiratory care for an acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). The purposes of alveolar recruitment are an improvement in pulmonary gas exchange and the protection of atelectrauma. This study examined the effect and safety of the alveolar RM using pressure control ventilation (PCV) in early ALI and ARDS patients. Methods: Sixteen patients with early ALI and ARDS who underwent alveolar RM using PCV were enrolled in this study. The patients data were recorded at the baseline, and 20 minutes, and 60 minutes after alveolar RM, and on the next day after the maneuver. Alveolar RM was performed with an inspiratory pressure of $30cmH_2O$ and a PEEP of $20cmH_2O$ in a 2-minute PCV mode. The venous $O_2$ saturation, central venous pressure, blood pressure, pulse rate, $PaO_2/FiO_2$ ratio, PEEP, and chest X-ray findings were obtained before and after alveolar RM. Results: Of the 16 patients, 3 had extra-pulmonary ALI/ARDS and the remaining 13 had pulmonary ALI/ARDS. The mean PEEP was 11.3 mmHg, and the mean $PaO_2/FiO_2$ ratio was 130.3 before RM. The $PaO_2/FiO_2$ ratio increased by 45% after alveolar RM. The $PaO_2/FiO_2$ ratio reached a peak 60 minutes after alveolar RM. The Pa$CO_2$ increased by 51.9 mmHg after alveolar RM. The mean blood pressure was not affected by alveolar RM. There were no complications due to pressure injuries such as a pneumothorax, pneumomediastinum, and subcutaneous emphysema. Conclusion: In this study, alveolar RM using PCV improved the level of oxygenation in patients with an acute lung injury and acute respiratory distress syndrome. Moreover, there were no significant complications due to hemodynamic changes and pressure injuries. Therefore, alveolar RM using PCV can be applied easily and safely in clinical practice with lung protective strategy in early ALI and ARDS patients.

A Study on the Improvement of Flexible Working Hours (탄력적 근로시간제 개선에 대한 연구)

  • Kwon, Yong-man
    • Journal of Venture Innovation
    • /
    • 제5권3호
    • /
    • pp.57-70
    • /
    • 2022
  • In modern industrial capitalism, the relationship between the provision of work and the receipt of wages has become an important principle governing society. According to the labor contract, the wages provided by entrusting the right to dispose of one's labor to the employer are directly compensated, and human life should be guaranteed and reproduced with proper rest. The establishment of labor relations under free contracts represents a problem in protecting workers, and accordingly, the maximum of working hours is set as a minimum right for workers, and the standard for minimum rest is set and assigned. The reduction of working hours is very important in terms of the quality of life of workers, but it is also an important issue in efficient corporate activities. As of 2020, Korea has 1,908 hours of annual working hours, the third lowest among OECD 37 countries in the happiness index surveyed by the Sustainable Development Solution Network(SDSN), an agency under the United Nations. Accordingly, the necessity of reducing working hours has been recognized, and the maximum working hours per week has been limited to 52 hours since 2018. In this situation, various working hours are legally excluded as a way to maintain the company's value-added creation and meet the diverse needs of workers, and Korea's Labor Standards Act restricts flexible working hours within three months, flexible working hours exceeding three months, selective working hours, and extended working hours. However, in the discussion on the application of the revised flexible working hours system in 2021 and the expansion of the settlement unit period recently discussed, there is a problem with the flexible working hours system, which needs to be improved. Therefore, this paper aims to examine the problems of the flexible working hours system and improvement measures. The flexible working hours system is a system that does not violate working hours even if the legal working hours are exceeded on a specific day or week according to a predetermined standard, and does not have to pay additional wages for excessive overtime work. It is mainly useful as a form of shift work in manufacturing, sales service, continuous business or electricity, gas, water, and transportation for long-term operations. It is also used as a way to shorten working hours, such as expanding holidays through short working days. However, if the settlement unit period is expanded, it is disadvantageous to workers as the additional wages that workers can receive will not be received. Therefore, First, in order to expand the settlement unit period currently under discussion, additional wages should be paid for the period expanded from the current standard. Second, it is necessary to improve the application of the flexible working hours system to individual workers to have sufficient consultation with individual workers in a written agreement with the worker representative, Third, clarify the allowable time for extended work during the settlement unit period, and Fourth, limit the daily working hours or apply to continuous rest. In addition, since the written agreement of the worker representative is an important issue in the application of the flexible working hours system, it is necessary to secure the representation of the worker representative.

The Patterns of Change in Arterial Oxygen Saturation and Heart Rate and Their Related Factors during Voluntary Breath holding and Rebreathing (자발적 호흡정지 및 재개시 동맥혈 산소포화도와 심박수의 변동양상과 이에 영향을 미치는 인자)

  • Lim, Chae-Man;Kim, Woo-Sung;Choi, Kang-Hyun;Koh, Youn-Suck;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
    • /
    • 제41권4호
    • /
    • pp.379-388
    • /
    • 1994
  • Background : In sleep apnea syndrome, arterial oxygen saturation($SaO_2$) decreases at a variable rate and to a variable degree for a given apneic period from patient to patient, and various kinds of cardiac arrythmia are known to occur. Factors supposed to affect arterial oxygen desaturation during apnea are duration of apnea, lung voulume at which apnea occurs, and oxygen consumption rate of the subject. The lung serves as preferential oxygen source during apnea, and there have been many reports related with the influence of lung volume on $SaO_2$ during apnea, but there are few, if any, studies about the influence of oxygen consumption rate of an individual on $SaO_2$ during breath holding or about the profile of arterial oxygen resaturation after breathing resumed. Methods : To investigate the changes of $SaO_2$ and heart rate(HR) during breath holding(BH) and rebreathing(RB) and to evaluate the physiologic factors responsible for the changes, lung volume measurements, and arterial blood gas analyses were performed in 17 healthy subjects. Nasal airflow by thermistor, $SaO_2$ by pulse oxymeter and ECG tracing were recorded on Polygraph(TA 4000, Gould, U.S.A.) during voluntary BH & RB at total lung capacity(TLC), at functional residual capacity(FRC) and at residual volume(RV), respectively, for the study subjects. Each subject's basal metabolic rate(BMR) was assumed on Harris-Benedict equation. Results: The time needed for $SaO_2$ to drop 2% from the basal level during breath holding(T2%) were $70.1{\pm}14.2$ sec(mean${\pm}$standard deviation) at TLC, $44.0{\pm}11.6$ sec at FRC, and $33.2{\pm}11.1$ sec at RV(TLC vs. FRC, p<0.05; FRC vs. RV, p<0.05). On rebreathing after $SaO_2$ decreased 2%, further decrement in $SaO_2$ was observed and it was significantly greater at RV($4.3{\pm}2.1%$) than at TLC($1.4{\pm}1.0%$)(p<0.05) or at FRC($1.9{\pm}1.4%$)(p<0.05). The time required for $SaO_2$ to return to the basal level after RB(Tr) at TLC was not significantly different from those at FRC or at RV. T2% had no significant correlation either with lung volumes or with BMR respectively. On the other hand, T2% had significant correlation with TLC/BMR(r=0.693, p<0.01) and FRC/BMR (r=0.615, p<0.025) but not with RV/BMR(r=0.227, p>0.05). The differences between maximal and minimal HR(${\Delta}HR$) during the BH-RB manuever were $27.5{\pm}9.2/min$ at TLC, $26.4{\pm}14.0/min$ at RV, and $19.1{\pm}6.0/min$ at FRC which was significantly smaller than those at TLC(p<0.05) or at RV(p<0.05). The mean difference of 5 p-p intervals before and after RB were $0.8{\pm}0.10$ sec and $0.72{\pm}0.09$ sec at TLC(p<0.001), $0.82{\pm}0.11$ sec and $0.73{\pm}0.09$ sec at FRC(p<0.025), and $0.77{\pm}0.09$ sec and $0.72{\pm}0.09$ sec at RV(p<0.05). Conclusion Healthy subjects showed arterial desaturation of various rates and extent during breath holding at different lung volumes. When breath held at lung volume greater than FRC, the rate of arterial desaturation significantly correlated with lung volume/basal metabolic rate, but when breath held at RV, the rate of arterial desaturation did not correlate linearly with RV/BMR. Sinus arrythmias occurred during breath holding and rebreathing manuever irrespective of the size of the lung volume at which breath holding started, and the amount of change was smallest when breath held at FRC and the change in vagal tone induced by alteration in respiratory movement might be the major responsible factor for the sinus arrythmia.

  • PDF

Comparison of Effects of Normothermic and Hypothermic Cardiopulmonary Bypass on Cerebral Metabolism During Cardiac Surgery (체외순환 시 뇌 대사에 대한 정상 체온 체외순환과 저 체온 체외순환의 임상적 영향에 관한 비교연구)

  • 조광현;박경택;김경현;최석철;최국렬;황윤호
    • Journal of Chest Surgery
    • /
    • 제35권6호
    • /
    • pp.420-429
    • /
    • 2002
  • Moderate hypothermic cardiopulmonary bypass (CPB) has commonly been used in cardiac surgery. Several cardiac centers recently practice normothermic CPB in cardiac surgery, However, the clinical effect and safety of normothermic CPB on cerebral metabolism are not established and not fully understood. This study was prospectively designed to evaluate the clinical influence of normothermic CPB on brain metabolism and to compare it with that of moderate hypothermic CPB. Material and Method: Thirty-six adult patients scheduled for elective cardiac surgery were randomized to receive normothermic (nasopharyngeal temperature >34.5 $^{\circ}C$, n=18) or hypothermic (nasopharyngeal temperature 29~3$0^{\circ}C$, n=18) CPB with nonpulsatile pump. Middle cerebral artery blood flow velocity (VMCA), cerebral arteriovenous oxygen content difference (CAVO$_{2}$), cerebral oxygen extraction (COE), modified cerebral metabolic rate for oxygen (MCMRO$_{2}$), cerebral oxygen transport (TEO$_{2}$), cerebral venous desaturation (oxygen saturation in internal jugular bulb blood$\leq$50 %), and arterial and internal jugular bulb blood gas analysis were measured during six phases of the operation: Pre-CPB (control), CPB-10 min, Rewarm-1 (nasopharyngeal temperature 34 $^{\circ}C$ in the hypothermic group), Rewarm-2 (nasopharyngeal temperature 37 $^{\circ}C$ in the both groups), CPB-off and Post-CPB (skin closure after CPB-off). Postoperaitve neuropsychologic complications were observed in all patients. All variables were compared between the two groups. Result: VMCA at Rewarm-2 was higher in the hypothermic group (153.11$\pm$8.98%) than in the normothermic group (131.18$\pm$6.94%) (p<0.05). CAVO$_{2}$ (3.47$\pm$0.21 vs 4.28$\pm$0.29 mL/dL, p<0.05), COE (0.30$\pm$0.02 vs 0.39$\pm$0.02, p<0.05) and MCMRO$_{2}$ (4.71 $\pm$0.42 vs 5.36$\pm$0.45, p<0.05) at CPB-10 min were lower in the hypothermic group than in the normothermic group. The hypothermic group had higher TEO$_{2}$ than the normothermic group at CPB-10 (1,527.60$\pm$25.84 vs 1,368.74$\pm$20.03, p<0.05), Rewarm-2 (1,757.50$\pm$32.30 vs 1,478.60$\pm$27.41, p<0.05) and Post-CPB (1,734.37$\pm$41.45 vs 1,597.68$\pm$27.50, p<0.05). Internal jugular bulb oxygen tension (40.96$\pm$1.16 vs 34.79$\pm$2.18 mmHg, p<0.05), saturation (72.63$\pm$2.68 vs 64.76$\pm$2.49 %, p<0.05) and content (8.08$\pm$0.34 vs 6.78$\pm$0.43 mL/dL, p<0.05) at CPB-10 were higher in the hypothermic group than in the normothermic group. The hypothermic group had less incidence of postoperative neurologic complication (delirium) than the normothermic group (2 vs 4 patients, p<0.05). Lasting periods of postoperative delirium were shorter in the hypothermic group than in the normothermic group (60 vs 160 hrs, p<0.01). Conclusion: These results indicate that normothermic CPB should not be routinely applied in all cardiac surgery, especially advanced age or the clinical situations that require prolonged operative time. Moderate hypothermic CPB may have beneficial influences relatively on brain metabolism and postoperative neuropsychologic outcomes when compared with normothermic CPB.

A Study on Commodity Asset Investment Model Based on Machine Learning Technique (기계학습을 활용한 상품자산 투자모델에 관한 연구)

  • Song, Jin Ho;Choi, Heung Sik;Kim, Sun Woong
    • Journal of Intelligence and Information Systems
    • /
    • 제23권4호
    • /
    • pp.127-146
    • /
    • 2017
  • Services using artificial intelligence have begun to emerge in daily life. Artificial intelligence is applied to products in consumer electronics and communications such as artificial intelligence refrigerators and speakers. In the financial sector, using Kensho's artificial intelligence technology, the process of the stock trading system in Goldman Sachs was improved. For example, two stock traders could handle the work of 600 stock traders and the analytical work for 15 people for 4weeks could be processed in 5 minutes. Especially, big data analysis through machine learning among artificial intelligence fields is actively applied throughout the financial industry. The stock market analysis and investment modeling through machine learning theory are also actively studied. The limits of linearity problem existing in financial time series studies are overcome by using machine learning theory such as artificial intelligence prediction model. The study of quantitative financial data based on the past stock market-related numerical data is widely performed using artificial intelligence to forecast future movements of stock price or indices. Various other studies have been conducted to predict the future direction of the market or the stock price of companies by learning based on a large amount of text data such as various news and comments related to the stock market. Investing on commodity asset, one of alternative assets, is usually used for enhancing the stability and safety of traditional stock and bond asset portfolio. There are relatively few researches on the investment model about commodity asset than mainstream assets like equity and bond. Recently machine learning techniques are widely applied on financial world, especially on stock and bond investment model and it makes better trading model on this field and makes the change on the whole financial area. In this study we made investment model using Support Vector Machine among the machine learning models. There are some researches on commodity asset focusing on the price prediction of the specific commodity but it is hard to find the researches about investment model of commodity as asset allocation using machine learning model. We propose a method of forecasting four major commodity indices, portfolio made of commodity futures, and individual commodity futures, using SVM model. The four major commodity indices are Goldman Sachs Commodity Index(GSCI), Dow Jones UBS Commodity Index(DJUI), Thomson Reuters/Core Commodity CRB Index(TRCI), and Rogers International Commodity Index(RI). We selected each two individual futures among three sectors as energy, agriculture, and metals that are actively traded on CME market and have enough liquidity. They are Crude Oil, Natural Gas, Corn, Wheat, Gold and Silver Futures. We made the equally weighted portfolio with six commodity futures for comparing with other commodity indices. We set the 19 macroeconomic indicators including stock market indices, exports & imports trade data, labor market data, and composite leading indicators as the input data of the model because commodity asset is very closely related with the macroeconomic activities. They are 14 US economic indicators, two Chinese economic indicators and two Korean economic indicators. Data period is from January 1990 to May 2017. We set the former 195 monthly data as training data and the latter 125 monthly data as test data. In this study, we verified that the performance of the equally weighted commodity futures portfolio rebalanced by the SVM model is better than that of other commodity indices. The prediction accuracy of the model for the commodity indices does not exceed 50% regardless of the SVM kernel function. On the other hand, the prediction accuracy of equally weighted commodity futures portfolio is 53%. The prediction accuracy of the individual commodity futures model is better than that of commodity indices model especially in agriculture and metal sectors. The individual commodity futures portfolio excluding the energy sector has outperformed the three sectors covered by individual commodity futures portfolio. In order to verify the validity of the model, it is judged that the analysis results should be similar despite variations in data period. So we also examined the odd numbered year data as training data and the even numbered year data as test data and we confirmed that the analysis results are similar. As a result, when we allocate commodity assets to traditional portfolio composed of stock, bond, and cash, we can get more effective investment performance not by investing commodity indices but by investing commodity futures. Especially we can get better performance by rebalanced commodity futures portfolio designed by SVM model.

Effect of Additional 1 hour T-piece Trial on Weaning Outcome to the Patients at Minimum Pressure Support (최소압력보조 수준에서 추가적 1시간 T-piece 시도가 이탈에 미치는 영향)

  • Hong, Sang-Bum;Koh, Youn-Suck;Lim, Chae-Man;Ann, Jong-Jun;Park, Wann;Shim, Tae-Son;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
    • /
    • 제45권4호
    • /
    • pp.813-822
    • /
    • 1998
  • Background: Extubation is recommended to be performed at minimum pressure support (PSmin) during the pressure support ventilation (PSV). In field, physicians sometimes perform additional 1 hr T-piece trial to the patient at PSmin to reduce re-intubation risk. Although it provides confirmation of patient's breathing reserve, weaning could be delayed due to increased airway resistance by endotracheal tube. Methods: To investigate the effect of additional 1 hr T-piece trial on weaning outcome, a prospective study was done in consecutive 44 patients who had received mechanical ventilation more than 3 days. Respiratory mechanics, hemodymic, and gas exchange measurements were done and the level of PSmin was calculated using the equation (PSmin=peak inspiratory flow rate $\times$ total ventilatory system resistance) at the 15cm $H_2O$ of pressure support. At PSmin, the patients were randomized into intervention (additional 1 hr T-piece trial) and control (extubation at PSmin). The measurements were repeated at PSmm, during weaning process (in cases of intervention), and after extubation. The weaning success was defined as spontaneous breathing more than 48hr after extubation. In intervention group, failure to continue weaning process was also considered as weaning failure. Results: Thirty-six patients with 42 times weaning trial were satisfied to the protocol. Mean PSmin level was 7.6 (${\pm}1.9$)cm $H_2O$. There were no differences in total ventilation times (TVT), APACHE III score, nutritional indices, and respiratory mechanics at PSmin between 2 groups. The weaning success rate and re-intubation rate were not different between intervention group (55% and 18% in each) and control group (70% and 20% in each) at first weaning trial. Work of breathing, pressure time product, and tidal volume were aggravated during 1 hr T-piece trial compared to those of PSmin in intervention group ($10.4{\pm}1.25$ and $1.66{\pm}1.08$ J/L in work of breathing) ($191{\pm}232$ and $287{\pm}217$cm $H_2O$ s/m in pressure time product) ($0.33{\pm}0.09$ and $0.29{\pm}0.09$ L in tidal volume) (P<0.05 in each). As in whole, TVT, and tidal volume at PSmin were significantly different between the patients with weaning success ($246{\pm}195$ hr, $0.43{\pm}0.11$ L) and the those with weaning failure ($407{\pm}248$ hr, $0.35{\pm}0.10$L) (P<0.05 in each). Conclusion : There were no advantage to weaning outcome by addition of 1 hr T-piece trial compared to prompt extubation to the patient at PS min.

  • PDF

Preoperative Evaluation for the Prediction of Postoperative Mortality and Morbidity in Lung Cancer Candidates with Impaired Lung Function (폐기능이 저하된 폐암환자에서 폐절제술후 합병증의 예측 인자 평가에 관한 전향적 연구)

  • Perk, Jeong-Woong;Jeong, Sung-Whan;Nam, Gui-Hyun;Suh, Gee-Young;Kim, Ho-Cheol;Chung, Man-Pyo;Kim, Ho-Joong;Kwon, O-Jung;Rhee, Chong-H.
    • Tuberculosis and Respiratory Diseases
    • /
    • 제48권1호
    • /
    • pp.14-23
    • /
    • 2000
  • Background: The evaluation of candidates for successful lung resection is important. Our study was conducted to determine the preoperative predictors of postoperative mortality and morbidity in lung cancer patients with impaired lung function. Method; Between October 1, 1995 and August 31, 1997, 36 lung resection candidates for lung cancer with $FEV_1$ of less than 2L or 60% of predicted value were included prospectively. Age, sex, weight loss, hematocrit, serum albumin, EKG and concomitant illness were considered as systemic potential predictors for successful lung resection. Smoking history, presence of pneumonia, dyspnea scale(l to 4), arterial blood gas analysis with room air breathing, routine pulmonary function test were also included for the analysis. In addition, predicted postoperative(ppo) pulmonary factors such as ppo-$FEV_1$ ppo-diffusing capacity(DLco), predicted postoperative product(PPP) of ppo-$FEV_1%{\times}$ppo-DLco% and ppo-maximal $O_2$ uptake($VO_2$max) were also measured. Results: There were 31 men and 5 women with the median age of 65 years(range, 44 to 82) and a mean $FEV_1$ of $1.78{\pm}0.06L$. Pneumonectomy was performed in 14 patients, bilobectomy in 8, lobectomy in 14. Pulmonary complications developed in 10 patients; cardiac complications in 3, other complications(empyema, air leak, bleeding) in 4. Twelve patients were managed in the intensive care unit for more than 48 hours. Two patients died within 30 days after operation. The ppo-$VO_2$max was less than 10 ml/kg/min in these two patients. MVV was the only predictor for the pulmonary complications. However, there was no predictor for the post operative death in this study. Conclusions: Based on the results, MVV was the useful predictor for postoperative pulmonary complications in lung cancer resection candidates with impaired lung function In addition, ppo-$VO_2$max value less than 10 ml/kg/min was associated with postoperative death, so exercise pulmonary function test could be useful as preoperative test. But further studies are needed to validate this result.

  • PDF

The effects of aqueous extracts of plant roots on germination of seeds and growth of seedings (식물근의 추출물질이 종자발아 및 유식물의 생장에 미치는 영향)

  • Chan-Ho Park
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • 제4권1호
    • /
    • pp.1-23
    • /
    • 1968
  • This study aimed at contributing to the improvement of cropping systems after finding out the effects of excrements and components of crop root influence on other crops as well as themselves. The following forage crops suitable for our country were selected for the present study. Aqueous extracts of fresh roots, aqueous extracts of rotting roots and aqueous solutions of excrements of red clover, orchard grass and brome grass were studied for the effects influencing the germination and growth of seedlings of red clover, ladino clover, lespedeza, soybean, orchard grass, Italian ryegrass, brome grass, barley, wheat, sorghum, corn and Hog-millet. In view of the possibility that the organic acid might be closely related to the excrements and components of crop root connected with soil sickness, the acid components of three species of roots were analysed by paper chromatography and gas chromatography method. The following results were obtained: 1. Effects of Aqueous Extracts of Fresh Roots : Aqueous extracts of red clover: The extracts inhibited the growth of seedlings of the ladino clover and lespedeza and also inhibited the development of most crops except that of sorghum among the Graminaceae. Aqueous extracts of orchard grass: The extracts promoted the seedlings growth of red clover and soybean, while it inhibited the germination and growth of orchard grass. There were no noticeable effects influencing other crops while it inhibited the growth of barley and Hog-millet. Aqueous extracts of brome grass: There was no effect on Italian ryegrass but there was an inhibiting effect on the other crops. 2. Effects of Aqueous Extracts of Rotting Roots : Aqueous extracts of red clover: The extracts promoted the seedling growth of red clover. But it reflected the inhibiting effects on other crops except sorghum. Aqueous extracts of orchard grass: The extracts promoted the growth of red clover, ladino clover, soybean and sorghun, while it inhibited the germination and rooting of barley and Hog-millet. Aqueous extracts of brome grass: The extracts gave the promotive effects to the growth of red clover, soybean and sorghum, but caused inhibiting effects on orchard grass, brome grass, barley and Hog-millet. 3. Effects of Aqueous Solutions of Excrements : The aqueous solution of excrements of red clover reflected the inhibition effects to the growth of Graminaceae, while the aqueous solutions of excrements of orchard grass and Italian ryegrass caused the promotive effects on the growth of red clover. 4. Results of Organic Acid Analysis : The oxalic acid, citric acid, tartaric acid, malonic acid, malic acid and succinic acid were included in the roots of red clover as unvolatile organic acid, and in the orchard grass and brome grass there were included the oxalic acid, citric acid, tartaric acid and malic acid. And formic acid was confirmed in the red clover, orchard grass and brome grass as volatile organic acid. In consideration of the results mentioned in above the effects of excrements and components of roots found in this studies may be summarized as follows. 1) The red clover generally gave a disadvantageous effect on the Graminaceae. Such trend was considered chiefly caused by the presence of many organic acids, namely oxalic, citric, tartaric, malonic, malic, succinic and formic acid. 2) The orchard grass generally gave an advantageous effect on the Leguminosae. This may be due to a few kinds of organic acid contained in the root, namely oxalic, citric, tartaric, malic and formic acid. Furthermore a certain of promotive materials for growth was noted. 3) As long as the root of brome grass are not rotten, it gave a disadvantageous effect on the Leguminosae and Graminaceae. This may be due to the fact that several unidentified volatile organic acid were also included besides the confirmed organic acid, namely oxalic, citric, tartaric, malic and formic acid. 5. Effects of Components in Roots to the Soil Sickness : 1) It was considered that the cause of alleged red clover's soil sickness did not result from the toxic components of the roots. 2) It was recognized that the toxic components of roots might be the cause of soil sickness in case the orchard grass and brome grass were put into the long-term single cropping. 6. Effects of Rooted Components to the Companion Crops in the Cropping System : a) In case of aqueous extracts of fresh roots and aqueous excrements (Inter cropping and mixed cropping) : 1) Advantageous combinations : Orchard grass->Red clover, Soybean, Italian ryegrass->Red clover, 2) Disadvantageous combinations : Red clover->Ladino clover, Lespedeza, Orchard grass, Italian ryegrass, Fescue Ky-31, Brome grass, Barley, Wheat, Corn and Hog.millet, Orchard grass->Lespedeza, Orchard grass, Barley and Hog-millet, Brome grass->Red clover, Ladino clover, Lespedeza, Soybean, Orchard grass, Brome grass, Barley, Wheat, Sorghum, Corn and Hog-millet, 3) Harmless combinations : Red clover->Red clover, Soybean and Sorghum, Orchard grass->Ladino clover, Italian ryegrass, Brome grass, Wheat, Sorghum and Corn, Brome grass->Italian ryegrass, b) In case of aquecus extracts of rotting roots(After cropping) : 1) Advantageous combinations : Red clover->Red clover and Sorghum, Orchard grass->Red clover, Ladino clover, Soybean, Sorghum, and Corn, Brome grass->Red clover, Soybean and Sorghum, 2) Disadvantageous combinations : Red clover->Lespedeza, Orchard grass, Italian ryegrass, Brome grass, Barley, Wheat, and Hog-millet Orchard grass->Barley and Hog-millet, Brome grass->Orchard grass, Brome grass, Barley and Hog-millet, 3) Harmless combinations : Red clover->Ladino clover, Soybean and Corn, Orchard grass->Lespedeza, Orchard grass, Italian ryegrass, Brome grass and Wheat Brome gass->Ladino clover, Lespedeza, Italian ryegrass and Wheat.

  • PDF