• Title/Summary/Keyword: 산소함량

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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
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    • v.35 no.6
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    • pp.420-429
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    • 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.

Change in Major Carbohydrate Contents in Diapausing and Nondiapausing Pupae of the Fall Webworm, Hyphantria cunea (흰불나방(Hyphantria cunea D.)의 휴면용과 비휴면용에서 탄수화물 함량의 변화)

  • Choi, Mann-Yeon;Boo, Kyung-Saeng
    • Korean journal of applied entomology
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    • v.26 no.3 s.72
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    • pp.145-150
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    • 1987
  • Carborhydrate contents were compared between diapausing and non-diapausing pupae of the fall webworm, Hyphantria cunea DRURY. Glycogen content in the whole body of diapausing pupae kept at $-5{\pm}1^{\circ}C$ was less than that of those left at room temperature, while the amounts of trehalose and sorbitol showed the reverse trend. The osmotic pressure of haemolymph was higher in diapausing pupae than that in non-diapausing pupae. The mean oxygen consumption rate of diapausing pupae was $4{\sim}6.7$ times less than that of non-diapausing, normal pupae.

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Development of Manufacturing Process of Pure Titanium Wire to make Eyewear Frame (안경용 순티타늄 wire 제조 공정개발)

  • Choi, Gye-Hun;Kim, Sang-Yeoun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.3
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    • pp.1105-1110
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    • 2011
  • After pure titanium Ingot(G2) with 400mm in diameter was manufactured, the analysis of its ingredients showed that the oxygen content was 0.073wt% and the iron content was 0.03wt%, which made ASTM Gr.2 standardization satisfactory. The processed titanium ingot produced 42mm wire rod, and hot rolling of 18th phase produced 9mm wire rod. The hardness analysis of 15.8mm wire rod, which was processed in hot rolling of 10th phase from the surface to the center, resulted in almost constant value with Hv150~200. The last 9mm wire rod had a different yield strength and elongation percentage depending on the temperature as it was led in to a hot roller. However, tensile strength revealed an approximate value and made ASTM B863 standardization satisfactory.

Effects of Acid Modification on Pb(II) and Cu(II) Adsorption of Bamboo-based Activated Carbon (대나무 활성탄의 산 개질이 납과 구리 이온의 흡착에 미치는 영향)

  • Lee, Myoung-Eun;Chung, Jae-Woo
    • Journal of the Korea Organic Resources Recycling Association
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    • v.24 no.1
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    • pp.3-10
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    • 2016
  • Effects of acid ($HNO_3$ and HCl) modification on the adsorption properties of Pb(II) and Cu(II) onto bamboo-based activated carbon (BAC) were investigated through a series of batch experiments. The carbon content increased and oxygen content decreased with acid treatment. $HNO_3$ induced carboxylic acids and hydroxyl functional groups while HCl added no functional group onto BAC. The pseudo-second order model better described the kinetics of Pb(II) and Cu(II) adsorption onto experimented adsorbents, indicating that the rate-limiting step of the heavy metal sorption is chemical sorption involving valency forces through sharing or exchange of electrons between the adsorbate and the adsorbent. The equilibrium sorption data followed both Langmuir and Freundlich isotherm models. The adsorption capacities of BAC were affected by the surface functional groups added by acid modification. The adsorption capacities were enhanced up to 36.0% and 27.3% for Pb(II) and Cu(II), respectively by the $HNO_3$ modification, however, negligibly affected by HCl.

Variation of Yield and Oxygen Content of SiC-Based Ceramics with the Conversion Processes of PCS (PCS의 전환공정에 따른 SiC세라믹스 수율 및 산소 함량 변화)

  • Kim, Joung-Il;Kim, Weon-Ju;Park, Ji-Yeon
    • Journal of the Korean Ceramic Society
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    • v.42 no.3 s.274
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    • pp.188-192
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    • 2005
  • The conversions to SiC-based ceramics of a polycarbosilane (PCS) with and without oxidation curing were carried out. A yield and an oxygen content of conversed SiC-based ceramics were evaluated. The weight losses of conversed SiC-based ceramics by both processes analyzed to estimate the high temperature stability after heat treatment at high temperature in vacuum. The yield of SiC­based ceramics after oxidation curing was higher than that without curing process. However, the weight loss of SiC-based ceramics with oxidation curing was larger than that without curing process after heat treatment.

Barrier Property and Morphology of Biaxially Oriented PP/EVOH Blend Film (이축연신 PP/EVOH 블렌드 필름의 차단 성질 및 모폴로지)

  • 여종호;이종훈;박찬석;이기준;남재도
    • Polymer(Korea)
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    • v.24 no.6
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    • pp.820-828
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    • 2000
  • In this study, biaxially oriented film process was used to improve barrier property of polypropylene (PP)/ethylene-vinyl alcohol copolymer (EVOH) blends by inducing a laminar morphology of the dispersed phase in the matrix phase. In order to examine the extent of deformation during melt extrusion process, the rheological properties of the resins were measured and the viscosity ratio of the dispersed phase to the continuous phase was determined. The effects of compatibilizer content, draw ratio, and draw temperature on the oxygen permeability and morphology of biaxially drawn blend films were studied. The laminar morphology of the EVOH phase with a larger area of thinner layer induced by biaxial orientation was found to result in a significant increase in oxygen barrier property of PP/EVOH (85/15) blends by about 10 times relative to the pure PP When both PP-g-MAH and ionomer were used as the compatibilizers, there existed an optimum level of compatibilizer content for obtaining improved barrier properties with a well developed laminar structure. In addition, higher draw ratio and draw temperature were found to be more favorable processing conditions in obtaining higher barrier blends.

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Production of Single Cell Lipid and Treatment of Wastewater Alcohol Manufactory (알코올 발효공장의 폐수처리를 겸한 단세포지질의 생산)

  • 이찬용;김종관이계호
    • KSBB Journal
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    • v.8 no.2
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    • pp.172-177
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    • 1993
  • In order to reduce BOD of wastewater from alcohol distillery manufactory, the production of single cell lipid was attempted. Among five yeast strains tested, Rhodotorula glutinis was most desirable for lipid production. Wastewater was treated with 2N NaOH and used as a medium. The optimum pH and temperature for lipid production were found to be 5.0 and $30^{\circ}C$, respectively. The addition of monobasic phosphate was good for cultivation of Rhodotorula glutinis. The C/N ratio was an important factor for lipid production and composition. The best C/N ratio was 50 for the production of single cell lipid. By cultivation Rhodctorula glutinis for 4 days, 4g/L of single cell lipid was harvested and BOD of wastewater reduced by 88.7%.

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A Study on the Characteristics of Humic Materials Extracted from Plant Residues (composts) -II. Oxygen-containing Functional Groups and Infrared (IR) Spectra of Fulvic Acid Fractions (식물성(植物性) 유기물질(有機物質)의 부숙과정중(腐熟過程中) 부식특성(腐植特性)에 관(關)한 연구(硏究) -II. Fulv 산중(酸中)에 함유(含有)되어 있는 효소함유작용기(酵素含有作用基)와 적외선(赤外線) spectrum)

  • Kim, Jeong-Je;Shin, Young-Oh
    • Korean Journal of Soil Science and Fertilizer
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    • v.20 no.4
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    • pp.341-349
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    • 1987
  • Fulvic acids extracted from seven plant materials were tested. The IR spectra and the data obtained from chemical analyses in terms of oxygen-containing functional groups complemented one another. Selected samples covered straws of grain crops (rice, barley, wheat and rye), hay of wild grass, and leaves of trees (deciduous and coniferous). 1. No significant variation in IR spectra of fulvic acids was observed among samples taken from different plant residues and at different stages of humification. 2. Oxygen-containing functional goups, such as carboxyls, phenolics, alcoholics, carbonyls, and quinones were identified on IR spectra and confirmed by chemical analyses. 3. The acidity of fulvic acids was directly related with the content of carboxyl groups. 4. Alcoholic hydroxyl groups predominated over phenolic hydroxyls. 5. The major part of fulvic acid structure appeared to be strongly aliphatic in many respects of chemical characteristics.

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Changes in Functional Groups of Protein by Lipid Deterioration in the Biological System of Rice Bran (미강 저장 중 지방의 산패에 따라 생성된 산화 지질이 단백질의 기능기에 미치는 영향에 관한 연구)

  • Song, Yeong-Ok;Choi, Hong-Sik
    • Korean Journal of Food Science and Technology
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    • v.22 no.5
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    • pp.596-601
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    • 1990
  • The effects of peroxidized lipid on the protein in the biological system of rice bran was studied by determining the changes in the content of functional groups under two different storage conditions. One stored at controlled atmosphere of $35^{\circ}C$ with relative humidity 65% and the other one was exposed to the air of $25^{\circ}-30^{\circ}C$ with relative humidity 70-90%. The lipid peroxidation started after the lipolysis was almost completed. The autoxidation occurred much faster in the bran exposed to the air than that stored in the controlled atmosphere. Substantial changes in the physiochemical characteristics were observed in all of the major functional groups in both of the samples. The content of sulfhydryl and available lysine decrease·1 as lipid peroxidation progressed. Protease activity was lost almost completely. Protein solubility and in vitro digestibility also decreased during storage. The lipid peroxidation and contents of major protein functional groups were significantly correlated (p<0.05) and the correlation coefficients were higher than -0.8, for the both of the sample. peroxidized lipid was found to deteriorate protein in the biological system as well.

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Diapause-initiation Stage and Changes in Proteins of the Fall Webworm (Hyphantria cunea Drury) Pupae (흰불나방의 용휴면이 결정되는 시기와 용 체내단백질의 변화)

  • 박노중;부경쟁
    • Korean journal of applied entomology
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    • v.27 no.1
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    • pp.6-13
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    • 1988
  • Studies were carried out to investigate the diapause-sensitive stage, the effect of 20-hydroxye- cdysone on diapausing pupae and the changes in pupal proteins of the fitll webworm, HYPha¬ntria cunea Drury. The stage sensitive to diapause-inducing photoperiod lies between 5th and 15th day of the larval development. And the oxygen consumption rate of diapausebound pupae decreased to a mean level of $30mu$l $O_{2}$/g/hr. The 20-hydroxyecdysone was effective in raising the respiratory acivity of 2.5% homogenate of the diapausing fall webworm pupae and in causing a normal adult development of the diapause-bound pupae. The soluble protein content rapidly declined in normally-developing pupae, but in diapause-bound pupae it was more or less static with much higher quantity. And protein bands separated from fat body of diapause¬bound pupae were different from those of nondiapausing pupae.

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