• The Korean Journal of Physiology
• /
• 제27권1호
• /
• pp.67-77
• /
• 1993

Acute and chronic effects of ethanol (EOH) administration on the cardiovascular and hormonal responses to repeated hemorrhage were investigated in conscious normotensive Wistar rats and spontaneously hypertensive rats (SHR). The chronic EOH treated group received 5% EOH (vol/vol) ad libitum in the drinking water far the first week,10% for the last 2 weeks, and 20% for the last 5 weeks from the age of 6 weeks. The EOH free group received tap water. Chronic EOH and EOH free groups were randomly subdivided into acute EOH infusion and control groups. Under ether anesthesia, catheters were inserted into the femoral vein and both femoral arteries. After rats regained consciousness and their blood pressure was stabilized, responses to quick hemorrhage (5 ml/kg BW) were tested. In the acute EOH infusion group, hemorrhage was induced 20 min after EOH infusion (1.0 g/kg BW), Baroreceptor reflex sensitivity was assessed by the ratio of changes in hen.1 rate and mean arterial pressure (${\Delta}HR/{\Delta}MAP$) immediately after the hemorrhage. Chronic EOH administration elevated MAP in Wistar rats. During acute EOH infusion, MAP do- creased and HR increased in all groups. In comparison to EOH free control rats, acute or chronic EOH treated rats showed a greater reduction in MAP and a smaller elevation in heart rate in response to a hemorrhage. The degree of MAP reduction was significantly greater in SHR than in Wistar rats. Both the acute and chronic EOH administration attenuated the baroreceptor reflex and retarded MAP recovery, again the trend being much more prominent in SHR. The increase in plasma vasopressin and lenin concentrations after hemorrhage were intensified by the chronic EOH administration. SHR showed a greater vasopressin response but a smaller lenin response than Wistar rats. These results indicate that the EOH treated rats, particularly SHB, are prone to shock by a hemorrhage, which may be partly attributed to an impaired baroreceptor reflex function.

• 한국자연치유학회지
• /
• 제10권2호
• /
• pp.86-92
• /
• 2021

배경: 약용식물 속새 풀에서 항산화물질의 존재는 확인되지 않았다. 목적: 본 연구는 속새 풀의 추출물의 항산화와 elastase inhibition 효과를 조사하는 것이었다. 방법: 속새의 줄기와 뿌리 부분을 채집하여 열수(HW) 및 에틸알코올(70EOH, 100EOH)로 추출한 물질들의 항산화 기능을 측정하였다. 결과: 줄기의 추출 수율은 HW추출에서 에틸알코올 추출보다 높았다. 폴리페놀 함유량은 줄기보다 뿌리 추출물에서는 유의하게 높았다. 70EOH 추출물의 총 플라보노이드 함량은 줄기 보다는 뿌리 추출물에서 유의하게 높았다. 뿌리 추출액의 elastase 저해 기능은 추출액 100 ppm에서는 46%의 효과가 있었고, 줄기에서는 49%의 효과가 있었다. ABTS 유리기 소거 기능 순서는 추출액 50 ppm 농도에서는 HW<70EOH<100EOH< 비타민E(99.7%)의 비율로 제거되었다. DPPH 유리기 소거능의 순서는 추출물 농도가 100 ppm일 때에 HW<100EOH<70EOH<비타민E(96.2%)로 나타났다. 양성 대조군인 비타민E의 제거율은 다른 추출물보다도 신속하고도 높게 진행되었다. 결론: 속새 풀 추출물에는 다량의 항산화물질이 존재하며 엘라스타제 저해 기능 효과도 높게 나타났다. 그런고로 속새 풀은 중요한 기능성 식물 중의 하나라고 판단한다.

• The Korean Journal of Physiology
• /
• 제29권1호
• /
• pp.91-102
• /
• 1995

The role of neurohumoral mechanisms in the regulation of cardiovascular functions and the effects of ethanol (EOH) on these mechanisms were examined in hemorrhaged conscious Wistar rats. The rats were bled at a constant rate (2 ml/kg/min) through the femoral artery until mean arterial pressure (MAP) was reduced by 30 mmHg. We studied the responses to hemorrhage 1) under normal conditions (Normal), and after pretreatments with 2) neural blockade (NB), pentolinium, 3) arginine vasopressin V1-receptor antagonist (AVPX) + NB, 4) angiotensin II ATI-receptor antagonist (AngIIX) + NB, 5) combined humoral blockade (HB), and 6) neurohumoral blockade. Intravenous administration of 30% EOH (6.3 ml/kg) attenuated the baroreceptor reflex sensitivity, and enhanced the depressor action of AngIIX. During hemorrhage, NB produced a faster fall ill MAP than Normal both in the saline and EOH groups. However, HB accelerated the rate of fall in MAP only in the EOH group. The recovery from hemorrhagic hypotension was not different between NB and Normal rats, but was attenuated in HB rats in the saline group. Under NB, AngIIX, but not AVPX, retarded the recovery rate compared with NB alone. EOH attenuated the recovery of MAP after hemorrhage in Normal rats, but completely abolished the recovery in HB rats. We conclude that 1) the maintenance of MAP during hemorrhage is mediated almost entirely by the autonomic functions, 2) angiotensin II plays an important role in the recovery from hemorrhagic hypotension, but AVP assumes little importance, 3) AVP release largely depends on the changes in blood volume, whereas renin release depends on the changes in blood pressure rather than blood volume, and 4) EOH increases the dependence of cardiovascular regulation on angiotensin II and impairs the recovery from hemorrhagic hypotension through the attenuation of autonomic functions.

• 한국환경보건학회지
• /
• 제23권1호
• /
• pp.66-73
• /
• 1997

This procedure describes the method for gas chromatographic determination of 31 organophosphorus and 28 organochlorine pesticides in 10g of spinach, tomato and onion. After the pesticides were extracted with several solvents, the amount of coextractives and recovery rates of acephate and methamidophos were calculated. Samples for organochlorine pesticides were cleaned up with florisil solid phase extraction columns. NaBH$_4$ was added to onion extracts, which contained sulfur compound. All the concentrated extracts were analyzed by gas chromatography with ECD and NPD. The smallest amount of coextractives resulted from the spinach samples extracted with 5% MeOH in ethyl acetate. 5% EOH in ethyl acetate had the highest extractability for acephate and methamidophos and gave the best overall performance as an extraction solvent. The ability of 5% EOH in ethyl acetate to extract various organophosphorus and organochlorine pesticides from spinach, tomato and onion was examined. Recovery of 59 insecticides ranged from 58.0% to 110.5%. The average recoveries of fortified spinach, tomato and onion were 90.08%, 94.54% and 84.90%, respectively.

• 콘크리트학회지
• /
• 제24권1호
• /
• pp.56-60
• /
• 2012

• 대한기계학회논문집A
• /
• 제35권5호
• /
• pp.549-554
• /
• 2011

최근 고온부품의 기술발전으로 고효율 가스터빈 발전설비들이 운전되고 있으나 국내의 가스터빈설비는 일일 기동정지를 반복 운전하므로써 열싸이클에 의한 블레이드와 베인의 재료물성은 급격히 나빠지고 있다. 현재 가스터빈 부품 교체와 정비는 제작사에 의존하고 있는 실정으로 이에 본 연구에서 독자적인 교체 및 정비 관리 기준을 위해 수명평가와 손상분석의 기초자료로 활용하고자 실제 운전된 가스터빈 고압 1단 블레이드와 베인의 사용시간별 손상거동을 분석하였다. 사용재의 블레이드는 등가운전시간(EOH)이 23,686, 27,909 및 52,859 이고 베인은 28,714 및 52,859 으로 운전시간이 증가함에 따라 ${\gamma}$'의 크기는 증가하고 형상은 구형 또는 판상으로 변형되었다. 블레이드는 leading edge영역, 베인은 center영역에서 가장 큰 미세조직의 열화가 관찰되었으며 이는 경도의 감소경향과 일치하였다. 열차폐 코팅층내 bond코팅층에서는 운전시간이 증가함에 따라 표면산화층의 두께가 증가하였다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2012년도 추계학술대회 논문집
• /
• pp.529-530
• /
• 2012

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2004년도 추계학술발표회 발표논문집
• /
• pp.271-272
• /
• 2004

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2005년도 춘계학술발표회
• /
• pp.83-84
• /
• 2005

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2005년도 춘계학술발표회
• /
• pp.85-86
• /
• 2005