• Journal of Korean Neurosurgical Society
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• 제64권3호
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• pp.346-358
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• 2021

Secondary neurulation is a morphological process described since the second half of the 19th century; it accounts for the formation of the caudal spinal cord in mammals including humans. A similar process takes place in birds. This form of neurulation is caused by the growth of the tail bud region, the most caudal axial region of the embryo. Experimental work in different animal species leads to questioning dogmas widely disseminated in the medical literature. Thus, it is clearly established that the tail bud is not a mass of undifferentiated pluripotent cells but is made up of a juxtaposition of territories whose fate is different. The lumens of the two tubes generated by the two modes of neurulation are continuous. There seem to be multiple cavities in the human embryo, but discrepancies exist according to the authors. Finally, the tissues that generate the secondary neural tube are initially located in the most superficial layer of the embryo. These cells must undergo internalization to generate the secondary neurectoderm. A defect in internalization could lead to an open neural tube defect that contradicts the dogma that a secondary neurulation defect is closed by definition.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.197-197
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• 2009

• Applied Microscopy
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• 제28권3호
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• pp.391-398
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• 1998

The morphological phenotype on ocellus of Drosophila rdgC mutant was observed with electron microscope. The result showed the particular phenotype that was not found in other retinal degenarative mutants. The most distinct difference was the orientation of photoreceptor cells. The photoreceptor cells did not attached to corneagenous cells but dropped under corneagenous cells and assembled around newly formed space. Enormous multivesicle bodies caused by the degeneration of photoreceptor cells were frequently found. Rhabdomeres were also severely degenerated in consequence of the mutant. Another degeneration was found in a part of photoreceptor cell, but the degeneration of subrhabdomeric cisternae (SRC) was not found. It was a ovious difference of rdgC comparing with other two retinal degenerative mutants, rdgA and rdgB. As a result, rdgC mutant was affected on the attachment between photoreceptor cells and corneageneous cells, and it suggested the defect of cell-cell attachment. In addition, rdgC mutant was accompanied by the defect not only in retina but nerve system. The results were agreed to the reference discussion that the rdgC molecule is exist in the nerve.

• Macromolecular Research
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• 제10권2호
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• pp.75-79
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• 2002

Organic materials have considerable attention as active semiconductors for device applications such as thin-film transistors (TFTs) and diodes. Pentacene is a p-type organic semiconducting material investigated for TFTs. In this paper, we reported the morphological and electrical characteristics of pentacene TFT films. The pentacene transistors showed the mobility of 0.8 $\textrm{cm}^2$/Vs and the grains larger than 1 ${\mu}{\textrm}{m}$. Deep-level transient spectroscopy (DLTS) measurements were carried out on metal/insulator/organic semiconductor structure devices that had a depletion region at the insulator/organic-semiconductor interface. The duration of the capacitance transient in DLTS signals was several ten of seconds in the pentacene, which was longer than that of inorganic semiconductors such as Si. Based on the DLTS characteristics, the energy levels of hole and electron traps for the pentacene films were approximately 0.24, 1.08, and 0.31 eV above Ev, and 0.69 eV below Ec.

• Journal of Chest Surgery
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• 제21권1호
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• pp.82-86
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• 1988

Tetralogy of Fallot with subarterial ventricular septal defect is known to be relatively common in the Far East. Among the 140 consecutive patients who underwent repair for tetralogy, 15 [10,7@] had this variant form of tetralogy. Though the degree of pulmonic stenosis seems only mild or moderately severe because of the absence of infundibular septum and relatively large size of pulmonary arteries in this type of tetralogy, it has a special surgical implication that a patch widening of the right ventriculotomy is necessary in every case to avoid the postoperative subpulmonic stenosis. A morphological and surgical features of tetralogy with subarterial VSD are presented.

• Current Research on Agriculture and Life Sciences
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• 제30권1호
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• pp.1-11
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• 2012

We identified cdf based on screening of the Arabidopsis cDNA library for functional suppressors of the AtBI-1 (a gene described to suppress the cell death induced by Bax gene expression in yeast). The cdf was located on Chr. V and was composed of 5 exons and 4 introns. It encodes a protein of 258 amino acid residues with a molecular weight of 28.8 kDa. The protein has 3 transmembrane domains in the C-terminal region. The cdf has one homologue, named cdf2, which was found in Arabidopsis. Like cdf, cdf2 also induced growth defect in yeast. The effect of the cell growth defect factor was somewhat lower than Bax. cdf could arrest the growth of yeast. Its localization to the nucleus was essential for the suppression of yeast cell proliferation. Morphological abnormality of intracellular network, which is a hallmark of AtBI-1, was attenuated by expression of cdf.

• Journal of Chest Surgery
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• 제12권2호
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• pp.119-126
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• 1979

This is one case report of the extremely rare congenital cardiac malformation, Double-outlet of left ventricle in corrected transposition of great arteries. 11-year-old boy complained acrocyanosis and exertional dyspnea, the parents noticed cyanosis since birth. Physical examination revealed acrocyanosis, clubbed fingers and toes, G-III pansystolic murmur on 2nd and 3rd ICS, LSB. Right heart catheterization revealed significant $O_2$ jump in ventricular level. Right and left ventriculography showed the both catheters arriving in the same ventricle i.e. anterior chamber, morphological left ventricle was in right and anterior position, simultaneous visualization of aorta and pulmonary artery and aorta locating anterior and right side of pulmonary artery. Echo cardiogram surely disclosed interventricular septum. Conclusively it was clarified that the patient has Double-outlet of left ventricle and corrected transposition of great arteries [S.L.D.]. Operation was performed to correct the anomalies under extracorporeal circulation with intermittent moderate hypothermia. Right-sided ventriculotomy disclosed the following findings. 1. Right-sided ventricle was morphological left ventricle. 2. Left-sided ventricle was morphological right ventricle. 3. Right side atrioventricular valve was bicuspid. 4. Left side atrioventricular valve was tricuspid. 5. Aortic valve was superior, anterior and right side of pulmonary valve. 6. Subpulmonary membranous stenosis. 7. Non-committed ventricular septal defect. We made a tunnel between VSD and aorta with Teflon patch so that arterial blood comes through VSD and the tunnel into aorta. After correction the patient needed assisted circulation for 135 min. to have adequate blood pressure. Postoperatively by any means, adequate blood pressure could not be maintained and expired in the evening of operation day.

• Journal of Chest Surgery
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• 제18권4호
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• pp.589-597
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• 1985

Congenitally corrected transposition of great arteries is a rare congenital heart anomaly. We experienced two case of corrected transposition of great arteries, one [S,L,L] and one [I, D,D] associated with patent foramen ovale, ventricular septal defect and pulmonary stenosis. The patent foramen ovales were closed directly under right atriotomy, the ventricular septal defects were closed with Dacron patch under morphological left ventriculotomy and the pulmonary valvular and subvalvular stenosis were corrected under pulmonary arteriotomy. The postoperatively course was uneventful in case I, the permanent pacemaker was implanted in case ll.

• Journal of Chest Surgery
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• 제17권3호
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• pp.339-345
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• 1984

Thirty four patients with a ventricular septal defect, aged 2 months to 24 years [median 2.33 years], had lung biopsies during open heart procedures to assess the degree of pulmonary vascular disease. The patients were divided into two groups according to their age; group 1 - under 2 years of age [15 patients], and group 2- over 2 years of age [19 patients]. The, pathologic change of the pulmonary arterioles was correlated with pre-operative hemodynamic data in 34 patients. There was no significant correlation between the severity of pulmonary vascular disease according to Heath-Edwards classification and the patients age [X2=1.8381, P=0.1751 ]. There was a significant correlation between degree of medial wall thickness and arteriolar diameter and the level of preoperative peak pulmonary artery pressure and peak systemic artery pressure [Pp/Ps]. Also, there was a good correlation between the preoperative pulmonary vascular resistance and systemic vascular resistance [Rp/Rs]. There was no significant correlation between wall thickness and Pp/Ps, and Rp/Rs below the age of 2 years. We conclude that, in patients over 2 years of age, there was a significant correlation between the medial wall thickness of the pulmonary arteriole and elevation of Pp/Ps and Rp/Rs. This is not true in patients under 2 years of age.

• Journal of Chest Surgery
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• 제35권8호
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• pp.580-583
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• 2002

배경: 선천성 심장병 환자들의 교정 수술 후 정확한 형태학적 혹은 혈역학적변화를 아는 것이 술 후 추가적으로 내과적 혹은 외과적인 치료가 필요로 하는가를 결성하는데 매우 중요하다. 심실중격결손 봉합술 후 잔류단락의 발생 빈도와 소량의 포편 주위 단락의 변화를 조사하였다. 대상 및 방법: 1995년 3월부터 1999년 12월까지 영남대학교의료원 흉부외과에서 영아기에 단순 심실중격결손으로 포편봉합술을 시행한 43명의 환자들을 대상으로 수술 후 심초음파를 시행하여 잔류단락 유무를 조사하였다. 결과: 전체 43례의 환자 중 수술 직후 잔류단락이 관찰된 환자는 11례로 26%에서 잔류단락이 발견되었으나 혈역학적으로 유의한 단락으로 재수술을 시행한 경우는 없었다. 단락의 발생빈도는 심실중격결손의 형태와 봉합을 위해 사용한 포편의 종류와는 무관하였다. 잔류단락이 발견된 환자 중 9명에서 단락의 소실을 확인할 수 있었으며 2례는 추적관찰에서 탈락하였다. 단락이 소실된 9명의 환자들의 단락이 마지막 확인된 기간은 평균 $4.2{\pm}3.6$개월 이었다. 결론: 수술 직후 포편 주위의 잔류단락은 종종 발견될 수 있으며 혈역학적으로 유의하지 않은 잔류단락은 대부분 6개월 이내에 자연 소실되었다.