• Clinical and Experimental Reproductive Medicine
• /
• 제23권1호
• /
• pp.67-71
• /
• 1996

During a 2-year period microsurgical vasovasostomies using permanent silicone stent(c-shaped stent with 0.6mm slit, 5mm in length, 0.8mm in outer diameter, 0.5mm in inner diameter) were performed in 30 patients for vasectomy revesal. The stent-assisted vasovasostomy(SVV) was intended to decrease the technical demand, the time requirement and the occurrence of reobstruction due to postoperative stricture. The effectiveness of the permanent silicone stent for vasovasostomy was compared with that of microsurgical two-layered vasovasostomy(VV). Sperms were present in all the ejaculates of the 25 men on semen analysis 1-2 months after SVV. Pregnancy occurred in 10 of 22 couples(45.5%) during 2-24 months of follow-up and it took 4-10 months(average 7.2 months) to get pregnant. Average operation time for the VV was 150 minutes and that for the SVV 125 minutes. Among 12 men who had sperms in the ejaculates 1-2 months after SVV, 4 revealed azoospermia 3-17 months postoperatively. Among the 4 patients with postoperative azoospermia, 2 underwent reoperation. On histopathologic examination, previously anastomsed sites showed obliterated lumen of the stent and strictures of vas proximal and/or distal to the stents due to granulation tissues. In conclusion, the SVV was not more efficacious in terms of patency and pregnancy rate than the VV.

• Journal of Chest Surgery
• /
• 제35권12호
• /
• pp.898-901
• /
• 2002

관상동맥 우회술에서 동맥도관만을 사용하는 방법은 동맥편이 가진 도관개통률의 우수성 때문에 복재정맥을 혼합하여 사용하는 관상동맥 우회술에 비해 좋은 단기 성적은 물론이고, 향상된 장기 성적을 기대할 수 있다. 그러나 때때로 내흉동맥 또는 다른 동맥편들의 사용이 가능하지 않은 경우가 있고, 특히 당뇨환자에서 양측 내흉동맥의 사용은 술 후 종격동염을 비롯한 합병증을 우려하여 사용이 꺼려지기도 한다. 또한 관상동맥 우회술의 재수술의 경우에는 사용가능한 동맥편 수의 제한이 문제가 되는데 이러한 경우 대체동맥편으로서 흉배동맥을 사용할 수 있으며, 저자들은 흉배동맥을 사용하여 시행했던 3례의 관상동맥 우회술을 보고하고자 한다.

• Journal of Chest Surgery
• /
• 제33권5호
• /
• pp.428-431
• /
• 2000

In the mid 1980's, the ITA(internal thoracic artery) graft was clearly recognized to be superior to the sapheonous vein graft in respect to long term patency. Therefore, there has been growing interest in the arterial conduit with the possibility of improving the long term result. We have been performing CABG with GEA since 1998 with the same purpose. For mid-term and long-term follow up, we have been performing postoperative coronary angiography. In this paper, a case of GEA spasm, a purported drawback of this conduit, during postoperative coronary anigiography and relieved by direct infusion of 200$\mu\textrm{g}$ isoket into the GEA is reported. The current case which exemplifies the spastic nature of RGEA is accompanied with coronary angiography.

• Journal of Chest Surgery
• /
• 제23권2호
• /
• pp.333-341
• /
• 1990

aortoiliac pattern, Group II; femoropopliteal pattern and Group g; tibioperoneal pattern. A majority of patients belonged to group I [27 cases], 8 patients came under group II .and none in group g. Thirty patients underwent bypass operation with autogenous saphenous vein or synthetic graft with or without concomitant lumbar sympathectomy. Remaining 5 patients were operated on with sympathectomy only, Bypass procedures were anatomic bypass in 22 cases: aortoiliac artery bypass in 11 cases, femoropopliteal artery bypass in 10 cases, sequential femoropopliteal artery bypass in one case and extra-anatomic bypass in 8 cases, axillary-bifemoral artery bypass in one case and femorofemoral artery bypass in 7 cases. Postoperative complications which mainly composed of superficial wound infection[5 cases] which were treated without any significant sequel in all cases and thrombosis[2 cases]. Three patients died whose causes of death were acute renal failure in 2 cases and myocardial infarction in other, The overall patency, rate was 70Zo in 5 years. In conclusion, the clinical pattern and operative outcome were similar to he western pattern and all cases of death did not related to operative procedures and ischemic symptoms were relieved by bypass operations except several cases. I think and recommend that all patients suffering chronic arterial insufficiency by atherosclerosis obliterans ought to be managed with urgent and adequate operative procedure.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제10권2호
• /
• pp.137-141
• /
• 2005

Though many insecticides are commercially available, development of resistance, pest resurgence and effects on non-target organisms led to the search for alternate insect pest management (IPM) strategy based on larval growth and reproductive fitness. Reproductive potential of insects depends on its acquiring of vitellogenic competence which is under hormonal control. Exogenous application of analogues of JR (JHAs) and ecdysterone could derail normal development and reproduction in insects by manipulating an array of physiological processes. In the rice pest, brown planthopper, Nilaparvata lugens, JHA, hydroprene induced metathetely from the fifth (final) instar nymphs in an age-dependent manner. Day 0 of the final instar showed highest sensitivity to induce this abnormal development. Adults emerged from treated day 3 nymphs looked normal. Both the morphotypes were reproductively incompetent and showed partial to complete sterility. Pre-adult exposure of the ovarian tissue to hydroprene suppressed mitotic division of germinal cells and induced abnormalities in the later s1ages of growth and differentiation of ovary in N. lugens. More over the nymphal exposure to hydroprene inhibited patency changes of follicular epithelium and affected competence of the follicles for yolk sequestration. In the absence of ovarian growth and oocyte differentiation, germarium found disintegrated, trophic core regressed and terminal oocytes resorbed. Hydroprene exposure to newly ecdysed brachypterous females did not affect ovarian development and egg production. Proper larval-adult transition appeared as a. prerequisite for vitellogenic competence in N. lugens for which the ovarian tissues must be exposed to ecdysterone in the internal milieu devoid of JH.

• 한국가시화정보학회지
• /
• 제14권1호
• /
• pp.33-39
• /
• 2016

Radio-cephalic arteriovenous fistula(RC-AVF) is the most recommended operation of achieving access for hemodialysis. However, it has high rates of early failure depending on the many haemodynamic conditions. To increase RC-AVF patency rate, many researches were performed by in-vitro experiment via artificial vessel and blood analogue fluid, and there were conflicting opinions about whether the non-Newtonian properties of blood have an influence on the flow in large arteries. To investigate the influence of viscoelasticity of blood within the RC-AVF, we fabricated three dimensional artificial RC-AVF and two kinds of blood analogue fluid. The velocity field of two fluids within the vessel were measured by micro-particle velocimetry(m-PIV) and compared with each other. The velocity profiles of both fluids for systolic phase were matched well while those for diastolic phase did not correspond. Therefore, it is desired to use non-newtonian fluid for in-vitro experiment of RC-AVF.

• Journal of Chest Surgery
• /
• 제16권1호
• /
• pp.91-96
• /
• 1983

A study was carried out to observe the clinical progress and results after modified Blalock-Taussing shunts on II patients with cyanotic complex heart diseases unsuitable for corrective surgery. The operation was performed by interposing a vascular prosthesis [PTEE] between the left subclavian artery and the left pulmonary artery. Vascular prostheses larger than the diameter of left subclavian artery were selected. The results were as follows: 1. The postoperative courses in 10 patients were uneventful without any complications. One patient died of low cardiac output syndrome immediate postoperatively. 2. The average value of RBC count before operations was 751.2291.68 [xl00]/cubic mm. It was decreased to 588.11 90.45 [xl 0,000]/cubic mm. After the operation. 3. The average value of Hemoglobin before operations was 20.07 3.01 mg/dl. The value was decreased to 15.361.68mg/dl after the operation. 4. The value of Hematocrit before operations was 62.878.89%. The value was decreased to 49.6 5.84% 5. Patency after the shunt operations using PTFE was good for maximal 16 months follow-up period. 6. The physiological impairment like anoxic spells, degree of cyanosis and other clinical symptoms were markedly improved after the shunt operations. Although a longer follow-up seems to be necessary to assess the validity of these shunts, the early results were encouraging.

• Journal of Chest Surgery
• /
• 제42권2호
• /
• pp.252-255
• /
• 2009

58세 남자 환자가 좌쇄골하동맥협착이 동반된 관상동맥 질환으로 하이브리드술식을 시행받았다. 쇄골하동맥에 대한 스텐트 삽입과 좌내흉동맥의 좌전하행지 문합을 포함한 심폐 바이패스 없이 관상동맥 우회술을 시행하였다. 수술 후 시행한 관상동맥 조영술과 컴퓨터 단층촬영(CT)상에서 이식편의 개방성은 양호하였고 스텐트의 삽입부위는 적절한 것으로 보였고 개방성도 양호하였다. 술 후 8일째 퇴원하였고, 현재 6개월째 외래 경과관찰 중이다.

• Journal of Chest Surgery
• /
• 제47권6호
• /
• pp.517-522
• /
• 2014

Background: This study reports the result of endovascular treatment for arterial occlusive disease limited to femoropopliteal lesions, focusing on the recurrence of symptoms instead of patency. Methods: This was a retrospective, single-center study. From April 2007 to November 2011, 48 limbs in 38 patients underwent endovascular stenting or balloon angioplasty to treat femoropopliteal arterial occlusive disease. The factors affecting the recurrence of symptoms were analyzed. Results: The mean age of the patients was $69.60{\pm}7.62$ years. Among the baseline characteristics of the patients, initial hyperlipidemia was the most important factor affecting the recurrence of symptoms (relative risk=5.810, p=0.031). The presence of a dorsal arch was also a significant factor (relative risk=0.675, p=0.047). Conclusion: The major factors that affect the recurrence of symptoms after endovascular treatment for femoropopliteal arterial occlusive lesions are hyperlipidemia and the presence of a dorsal arch. Therefore, the usage of lipid-lowering agents after endovascular treatment and taking the presence of a dorsal arch into consideration are important elements of managing the recurrence of symptoms.

• International Journal of Vascular Biomedical Engineering
• /
• 제1권1호
• /
• pp.41-47
• /
• 2003

The patency rates of small diameter vascular grafts are disappointing because of the formation of thrombus and intimal hyperplasia. Among the various factors influencing the success of graft surgery, the compliance and the size of a graft are believed to be the most important physical properties of a vascular graft. Mismatch of compliance and size between an artery and a graft alters anastomotic flow characteristics, which may affect the formation of intimal hyperplasia. Among the hemodynamic factors influencing the development of intimal hyperplasia, the wall shear stress is suspected as the most important one. The wall shear stress distributions are experimentally measured near the end-to-end anastomosis models in order to clarify the effects of compliance and diameter mismatch on the hemodynamics near the anastomosis. The effects of radial wall motion, diameter mismatch and impedance phase angle on the wall shear rate distributions near the anastomosis are considered. Compliance mismatch generates both different radial wall motion and instantaneous diameter mismatch between the arterial portion and the graft portion during a flow cycle. Mismatch in diameter seems to be affecting the wall shear rate distribution more significantly compared to radial wall motion. The impedance phase angle also affects the wall shear rate distribution.