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991.
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A graft with branches is used to reconstruct the extensively dissected thoracoabdominal aorta. Anastomoses of the proximal end of the main graft distal to the left subclavian artery and the side branch to the distal aneurysmal descending thoracic aorta were first undertaken after the preparation of both ends under the iliac vein-artery partial bypass. A main graft with a Y graft extension was anastomosed distally to iliac arteries. This permits the blood flow within the aneurysm and the main graft to the extremities until splanchnic and spinal cord arteries have individually been transferred to the main graft. Ischemic time of the splanchnic and spinal cord arteries, using this technique, can be minimized within 10 minutes to each in the total replacement of descending thoracic and abdominal aorta.  相似文献   
995.
Deoxyspergualin (DSG), an analogue of spergualin produced by B. laterosporus, has a strong immunosuppressive effect in various transplantation models. We have investigated the mechanism of donor-specific prolongation of survival time in rat kidney grafting by donor-specific blood transfusion (DST) and a short course of DSG. Lewis (LEW) kidney allografts were transplanted into fully allogeneic BN rats. Fresh, whole LEW blood 1.0 ml, was injected i.v. into BN rats 2 days prior to transplantation. Then, DSG, 6 mg/kg per day, was administered by i.m. injection on days 0, 1, and 2 after transplantation. The recipients were divided into five groups: group 1 (n=6) no treatment: group 2 (n=6) DST only; group 3 (n=7) DSG only; group 4 (n=7) DST and DSG; and group 5 (n=6), third party (ACI rats) blood transfusion and DSG. Lymphocytes (cervical lymph nodes) and serum were harvested from BN recipients on day 7 postgrafting. For suppressor cell assays, lymphocytes from BN recipients in each group were added as a third cell to the mixed lymphocyte reaction (MLC) between nontransplanted BN lymphocytes (responder) and LEW or other third party (PVGC, ACI, WKA rats) lymphocytes (stimulator). Antidonor lymphocytotoxic antibody (ADLA) was checked by microcytotoxicity assays. Median survival times (MST) for each group were: group 1, 10 days; group 1, 10 days; group 3, 13 days; group 4, 75 days; and group 5, 13 days. Remarkable prolongation of MST was only noted in group 4. In the suppressor cell assay, group 4 showed significant suppression (40%; P<0.05); the other groups did not show any suppression. This suppressive activity in group 4 was effective only during the MLC between BN and LEW, not during the MLC of third party-BN combinations. Thus, suppressor cells from DST/DSG-treated BN recipients appear to be donor-specific. In the microcytotoxicity assay, the only group that showed any ADLA was group 2, which was not treated with DSG. These results clearly show that both induction of donor-specific suppressor cells and inhibition of ADLA production are associated with the remarkable donor-specific prolongation of kidney allograft survival in DST/DSG-treated recipients.  相似文献   
996.
997.
The purpose of this study was to examine the intermediate (6-month) patency and healing characteristics of high-porosity expanded polytetrafluoroethylene (ePTFE) grafts with and without omentum wrap in a dog portal vein replacement model, compared with short-term (1-month) results. The grafts, either wrapped by omentum or not, were placed as portal vein replacements in 22 mongrel dogs. After 1 and 6 months, the grafts were retrieved and examined for patency and subjected to pathology study. Although the short-term patency rate in all grafts was 100%, regardless of the presence or absence of omentum wrap, the intermediate patency of high-porosity ePTFE without omentum wrap was very poor (20%). On the other hand, high-porosity ePTFE with omentum wrap had an intermediate patency rate of 100%. At 6 months, the high-porosity ePTFE grafts with omentum wrap were completely healed. The pseudointima was entirely replaced by thin fibrous tissue, with complete endothelial-like cell coverage throughout the graft. This result suggests that high-porosity ePTFE with omentum wrap could be a suitable prosthetic alternative to autogenous vein graft in portal vein reconstruction.  相似文献   
998.
A 51-year-old man who had a past history of gastric resection for medically uncontrollable gastric ulcer has loss of appetite that recurs periodically. And he has frequently presented spontaneous angina early in the morning since 1984. He was diagnosed as having variant angina by the documentation of typical ST elevation during anginal attack and also by showing coronary artery spasm (#2 and #12) during hyperventilation on coronary arteriography. A large quantity of calcium blocking agents and nitrates could not improve his symptoms. Lack of intracellular magnesium by loss of appetite was suspected from a daily excretion of urine magnesium (5.3 mEq) and magnesium tolerance test (56.7%). To confirm the effect of magnesium administration, the second coronary arteriography was performed. After magnesium sulphate (80 mEq, hourly) was injected, coronary artery spasm could not be induced by ergonovine. And orally magnesium oxide, calcium blocking agents and nitrates were started. Anginal attack disappeared with increasing urine magnesium.  相似文献   
999.
The tracheo-bronchial mucosa of 27 surgical patients with esophageal cancer was examined by bronchofiberscope postoperatively, and the changes of the mucosa were divided into four grades, i.e., GI: no change or slight redness only (7 cases), GII: Severe redness or erosion (7 cases), GIII: Ulcer formation (11 cases) and GIV: Necrosis of the mucosa (2 cases). All the GI-III changes were reversible. However, GIV change was irreversible. The biopsy specimens were taken from the mucosa of the tracheal bifurcation on the 7th postoperative day, showing squamous metaplasia in 9 of 13 patients. Bilateral modified neck and upper mediastinal lymph node dissections were performed in 18 of 27 patients. The change of the mucosa was judged as GIII or IV in 12 of 18 patients (67%), whereas the change was less significant in the remaining 6 patients. Namely, the degree of mucosal change did not necessarily correspond with the extent of lymph node dissection. The changes of the mucosa were considered to be brought about not only by tracheo-bronchial ischemia but also by injurious effects on the pulmonary parenchyma following aggressive lymph node dissection. The assessment of the degree of the mucosal change might be a useful indicator for postoperative management of esophageal cancer patients.  相似文献   
1000.
We report the first Japanese female patient with Walker-Warburg syndrome. She had generalized muscle hypotonia with hydrocephalus due to Dandy-Walker malformation and bilateral microphthalmia with opaque corneas. She had severe motor and mental retardation. Muscle histology reflected advanced changes of muscular dystrophy. We discuss the relationship between Fukuyama congenital muscular dystrophy and Walker-Warburg syndrome, both of which fall within a spectrum of developmental abnormalities with a common cause. In Fukuyama congenital muscular dystrophy, ocular abnormalities are less severe.  相似文献   
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