연두금파리(Lucillia illustris)의 용과 성체에서 정소의 미세구조변화와 정자형성과정

김우갑,김지현,이정원,강성훈 고려대학교 한국곤충연구소 1994 昆蟲硏究誌 Vol.20 No.1

연두금파리(Lucillia illustris)의 용과 성체에서 정소의 미세구조변화와 정자형성과정. 이정원, 강성훈, 김지현, 김우갑 (고려대학교 이과대학 생물학과) 昆蟲硏究誌. 20 : 1~13, 1994. 용 3일째부터 성충우화 후 5일까지 연두금파리(Lucilia illustris)의 정소를 적출하여 변태과정에서 정소의 미세구조변화와 정자형성과정에 대하여 광학 및 투과전자현미경으로 관찰하여 다음과 같은 결과를 얻었다. 웅성내부생식기는 한쌍의 정소, 수정관, 한쌍의 부속선, 사정관으로 구성되어 있으며, 각 정소는 하나의 타원형인 정소여포를 가지고 있었다. 같은 발생단계의 세포들은 정원세포다발, 정모세포다발, 정세포다발, 정자다발들을 이루고 있었다. 정소여포는 두층의 피초(sheath)로 둘러싸여져 있었다. 외초(outer sheath)에는 전자밀도가 높은 색소과립이 존재하였고, 내초(inner sheath)에는 미세섬유(microfibril)가 관찰되었으며, 성충이 되면서 색소과립의 수가 증가하고, 미세섬유도 매우 조밀하게 나타났다. 세포질교는 정원세포에서 정세포 시기까지 있어 한 피낭내에 세포들은 같은 분화단계를 나타내었다. 미토콘드리아는 초기 정세포에서 부핵(nebenkern)을 형성하고, 이들이 분열하여 크기가 같은 2개의 미토콘드리아 유도체로 신장하였다. 정세포가 신장하는 동안 핵에서는 바깥쪽에서부터 안쪽으로 염색체들이 점점 응축되었다. 미세소관은 핵의 신장시기에 많은 수로 형성되어 정세포의 신장을 유도하였다. 축사의 미세소관의 배열은 9+9+2이며, 성숙정자의 미부에 2개의 미토콘드리아 유도체사이에 전자밀도가 높은 막대모양의 물질이 일정하게 배열되어 있는 특징적인 구조를 나타내었다. We investigated the line structural changes and spermatogenesis of the tests from Lucilia illustris, using light microscope and transmission electron microscope. The male internal reproductive nigan consists vas defference a pair of nceessory glands, and a ejaculatory duct. Each testis is ceraposed of one follicle. Within the testes of different developmental stages, the cells at simllar developmental stage aggregate to form sperinatogonia bunele, sperinatocyte bundle, spermatid bundle, and sperm bundle which are embraced by a cyst. The layer of a testicular follicle consists of two sheath cell layers, outer sheath cell layer and inner sheath cell layer. The outer sheath cell layer contains electron-dense pigment granules, while the inner sheath cell layer is filled with microfibrlis. the granules in outer sheath cell layer and mierofibrils in inner sheath cell layer are richer in adult tests than in pual testis. All the cells in a cyst connect with each other by cytoplasmic bridges during spermatogenesis. The interconnection is responsible for the synchrony of differentiation in cyst. In early spermatid, mitochondria change into nebenkern. The nebenkern then divides into two mitochondrial derivatives. The paired mitochondrial derivatives eventually elongate around the axial fllaments. The chromosomes in nucleus appear to be more condensed while spermatid elongates. The chromosome condensation initiated from the outside within nucleus gradually progresses into the inside. Numerous microtubles which occur during nuclear elongation induce elongation of the spermatid. The middle piece of a sperm consists of the axon eme with 9+9+2 microtublar pattern and two same-sized mitochondrial derivatives between which the electron dense materials are located.

배양된 혈관내피세포에서 uncoupling protein 2 유전자 과발현이 세포내 산화스트레스 및 endothelin - 1 mRNA 발현에 미치는 영향

강효경,한정희,홍성관,김하영,남궁일성,박기영,박혜선,이재담,박중열,이인규,이기업 한국지질학회 2001 韓國脂質學會誌 Vol.11 No.2

방전 플라스마에 의한 CFC-12(CCl2F2)의 분해

황명환,우인성,조정국,강현춘,안형환,이한섭,강안수 한국산업안전학회 1999 한국안전학회지 Vol.14 No.3

Decomposition efficiency, power consumption, and applied voltage of CFC(Chlorofluorocarbon) were investigated by SPCY(surface induced discharge plasma chemical processing) reactor to obtain optimum process variables and maximum decomposition efficiencies. Decomposition efficiency of CFC-12 with various electric frequencies(5∼50㎑). flow rates (100∼1,000mL/min), initial concentrations(100∼1,000ppm), electrode materials(W, Cu. Al), electrode thickness(1, 2, 3mm) and reference gases(N₂, O₂, air) were measured and the products were analyzed with FT-IR. Experimental results showed that at the frequency of 10kHz, the highest decomposition efficiency of 92.7% for CFC-12 were observed at the power consumptions of 29.6W, respectively, and that decomposition efficiency decreased with increasing frequency above 20㎑ and decomposition efficiency per unit power were 3.13%/W for CFC-12. Decomposition efficiency was increased with increasing residence times and with decreasing initial concentration of pollutants. Decomposition efficiency was increased with increasing thickness of discharge electrode and the highest decomposition efficiency was obtained for the electrode diameter of 3mm. As the electrode material, decomposition efficiency was in order that tungsten(W), copper(Cu), aluminum (Al).

급성 골수성 백혈병(M6)에 합병된 중추성 요붕증 1 예

김성연,조보연,이홍규,고창순,민헌기,김병국,김노경,신찬수,이명식,강덕현,조종태 대한내과학회 1989 대한내과학회지 Vol.37 No.2

Leukemia is known to be an extremely rare cause of diabetes insipidus. We report a case of diabetes insipidus as a complication of leukemia. An 18 year-old man was admitted because of polyuria polydipsia and fever. Bone marrow aspiration and biopsy revealed the diagnosis of acute erythroleukemia (AML, M6). On the water deprivation test, the diabetes insipidus was confirmed to be of the central type. He was managed with intranasal vasopressin for diabetes insipidus with good response. Induction chemotherapy was administered without response, and the patient died of septicemia and respiratory failure 2 months after initial diagnosis. A short review of the literature related to this subject is also presented.

당뇨병유발백서에서 급성패혈증 병발시 적혈구막지질과산화의 변화

박성우,홍성관,유형준,장대영,강승식,유재명,임성희,최문기,노정우,이규만 대한당뇨병학회 1994 Diabetes and Metabolism Journal Vol.18 No.3

Cu-Al-Ni-Ti-Mn 합금의 변태특성 및 기계적 성질에 미치는 가공열처리의 영향

강조원,장우양,양권승,이영수,곽사호,김춘동,백승남 한국열처리공학회 1999 熱處理工學會誌 Vol.12 No.2

The distribution of the second phase, the change of transformation temperature and mechanical properties with thermomechanical treatment conditions were investigated by metallography, calorimetry, EDS, tensile test and fractography in a Cu-Al-Ni-Ti-Mn alloy. The cast structure revealed Ti-rich precipitates(X_L phase) between dendrite arms, which have been identified as (Cu,Ni)₂TiAl intermetallic compounds. By homogenizing above 900℃, the X_L phase was melted in the matrix, while the X_s phase was precipitated in matrix and the volume fraction of it was increased. When hot-rolled specimen was betatized below 750℃, recrystallization could not be observed. However, the specimen betatized above 800℃ was recrystallized and the grain size was about 50㎛, while X_s phase was precipitated in matrix. With raising betatizing temperature, M_s and A_s temperatures were fallen and transformation hysteresis became larger. The strain of the specimen betatized at 800℃ was 8.2% as maximum value. The maximum shape recovery rate could be obtained in the specimen betatized at 800℃ but it was decreased due to the presence of X_s phase with increasing betatizing temperature.

제 2 형 당뇨병에서 미세혈관 합병증과 대혈관 합병증의 대비

강문호,이기영,정연실,김홍규,서찬종,송광식,박혜영,이원기 대한당뇨병학회 2001 Diabetes and Metabolism Journal Vol.25 No.2

Background: Type 2 diabetes is a heterogeneous disease. As to its complications, microangiopathy predominantly develop in some patients while macroangiopathy is more predominant in others. Therefore, this study was performed to identify the factors associated with such dissociation. Methods: Type 2 diabetic patients were classified into the macro and microangiopathy groups by carotid intima-medial thickness (IMT) and the presence of severe diabetic retinopathy. Patients with IMT ≤ 0.83 mm and severe NPDR or PDR were assigned to microangiopathy group; those with IMT 0.84 mm and no diabetic retinopathy were assigned to macroangiopathy group. Of 95 patients studied, 14 were classified as microangiopathy group and 20 as macroangiopathy group. Results: When the microangiopathy and macroangiopathy groups were compared, the microangiopathy group were significantly younger at the time of examination and at the onset of diabetes, and had longer duration of diabetes. Percentage of patients receiving insulin treatment was significantly higher and plasma C-peptide significantly lower in the microangiopathy group. However, HDL-cholesterol levels were significantly lower in the macroangiopathy group. Furthermore, the multiple logistic regression analyses revealed that younger onset of type 2 diabetes was an independent factor that was associated with the acceleration of microangiopathy. Conclusion: This study suggests that the age at onset of diabetes is an important independent risk factor that is associated with predominant development of microangiopathy in type 2 diabetic patients.

Trip 형 고장력강판의 인장성질 및 점용접성

강창룡,김태일,김효정,김창규,이병우,이규현,이문용 한국열처리공학회 1998 熱處理工學會誌 Vol.11 No.4

The effects of retained austenite and carbon content in the retained austenite on the tensile strength-elongation balance and spot weldability of TRIP high strength steel sheet have been investigated. The retained austenite of granular type increased with increasing intercritical annealing and austempering temperature, and film type was increased with the increase of austempering time. The volume fraction of retained austenite increased with 'decreasing intereritical annealing temperature, and the maximum value was obtained at austempering temperature of 400℃. The values of tensile strength-elongation balance increased with decreasing intercritical annealing temperature and maximum value was obtained at austempering temperature of 400℃. The maximum value of tensile strength-elongation balance was obtained at a retained austenite content of about 12%. Tensile shear strength of the specimens with retained austenite was higher than that of the normalizing specimens. With increasing welding current and time, the tensile shear strengh and nugget diameter increased, while nugget thickness showed the peak value and then decreased. The optimum range of welding condition at the given welding pressure of 350kgf was 7-11㎄ and 10∼15 cycles.

고강도 오세템퍼주강의 기계적성질에 미치는 열처리 영향

문원진,김효정,김익수,강창용,이종남,박성부 한국열처리공학회 1998 熱處理工學會誌 Vol.11 No.4

The study was investigated on the effect of austenitiaing and austempering conditions on retained austenite amount and carbon contents in retained austenite and simultaneously the effect of these variation on hardness, tensile and impact properties. A material of as-cast condition is composed of bull's eye structure with ferrite surrounding spheroidized graphite having about 5-10㎛ size and matrix structure of pearlite. Then, the contents of spheroidized graphite was about 5%. The retained austenite and carbon contents in the retained austenite were increased with the increasing of austenitizing and austempering temperatures, while the retained austenite showed the peak value and is decreased with increasing of austempering time. With increasing of austenitizing temperature, tensile strength, elongation and impact absorb energy increased and hardness was almost not changed, while with increasing of austempering temperature, tensile strength and hardness decreased, whereas elongation and impact absorb energy was increased. With increasing of retained austenite amount, the tensile strength is slowly decreased but elongation was increased with direct proportion. Also, Impact absorb energy is shown identity value untile about 18%, but rapidly increased above it. Elongation and Impact absorb energy are strongly controlled by the amount of retained austenite, but tensile strength is affected with various factors such as retained austenite amount and bainitic morphology.

한국산 날치과(Beloniformes , Exocoetidae)어류 5 종의 분류학적 재검토

김종만,김진구,유정화,조선형,명정구,강충배,김용억 한국어류학회 2001 韓國魚類學會誌 Vol.13 No.2

Taxonomic review of the five flyingfishes, Parexocoetus mento (Valenciennes), Cheilopogon agoo (Temminck et Schlegel), Cheilopogon heterurus doederleini (Steindachner), Cheilopogon cyanopterus (Valenciennes), Hirundichthys oxycephalus (Bleeker) were carried out based on samples collected from the South sea and around sea of Jeju Island of Korea from 1996 to 1998. Parexocoetus mento (Valenciennes) and Cheilopogon cyanopterus (Valenciennes) were revealed as the unrecorded species in Korea, which were named as "Men-to-hwang-nal-chi" and "Ki-geom-nal-chi" respectively. Parexocoetus mento is differed from P. barchypterus in having no chin barbels in juveniles, and Cheilopogon cyanopterus is distinguished from C. agoo in the branched form of pectoral fin rays and from C. heterurus doederleini in the numbers of the dorsal fin ray and the color of pectoral fins.