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11.
Analogues of erythrocyte protein 4.1, spectrin and ankyrin were examined in the thyroid gland of pig and rat by immunohistochemical techniques. Analysis with immunofluorescence microscopy revealed that the peripheral cytoplasm and apical-lateral plasma membrane of follicle epithelial cells of thyroid glands were stained with antibodies against erythrocyte protein 4.1, spectrin, or ankyrin. The results indicate that membrane skeletal protein lattice might exist in thyroid follicle epithelial cells.  相似文献   
12.
Postinfarction left ventricular aneurysms are pathophysiologically divided into true, functional and false aneurysm. On 14 patients treated by aneurysmectomy, we studied the difference of pre- and post-operative cardiac function between true aneurysms (9 patients) and functional aneurysms (5 patients). The aneurysm area, which is expressed as the end-diastolic perimeter (akinetic or dyskinetic area/left ventricular silhouette), was 51.6 +/- 7.7% in the true aneurysms versus 35.7 +/- 6.0% in the functional aneurysms. Preoperatively, patients with a true aneurysm had a more severe clinical status than those with a functional aneurysm (Six of nine patients with a true aneurysm were in New York Heart Association functional class III or IV). Postoperatively, all patients except one with a true aneurysm and one with a functional aneurysm improved in clinical status. Nonaneurysmal EF, that is the function of the nonaneurysmal left ventricle, has a significant correlation to postoperative LVEF (r = 0.57, p less than 0.05). Nonaneurysmal EF was 54 +/- 4% in the true aneurysm group versus 51 +/- 16% in the functional aneurysm group. LVEF improved significantly (p less than 0.05) from 31 +/- 11% preoperatively to 55 +/- 10% postoperatively in the group of true aneurysm, but did not improved significantly from 43 +/- 12% to 50 +/- 9% in the functional aneurysm group. The postoperative akinetic area was 8.1 +/- 9.1% in the true aneurysm group versus 17.8 +/- 11.5% in the functional group. We conclude that larger and more adequate resection of aneurysms improves the cardiac function in the true aneurysm group more than in the functional aneurysm group.  相似文献   
13.
A rare case of a dissecting aneurysm of the P3 segment of the right posterior cerebral artery is presented that seems to have occurred in association with mild head injury. The patient was treated surgically because of repeated intramural hemorrhage and enlargement of the aneurysm. Proximal ligation produced thrombosis of the aneurysm without resulting in infarction in the region of the posterior cerebral artery. The mechanisms of the dissection, diagnosis, and treatment are briefly discussed.  相似文献   
14.
We report here the first described case of utilizing gadolinium-based contrast material as the contrast agent during a catheter intervention treatment for pulmonary artery stenosis. The patient, a male infant with complex heart disease associated with a right isomerism, had a history of severe allergic reaction to iodine-containing contrast agents. A combination of digital subtraction angiography and a gadolinium contrast agent, however, provided us with good-quality images both before and after balloon angioplasty without any associated complications. This method should therefore be considered as an alternative angiographic procedure in children with a high risk of iodine-related allergic complications.  相似文献   
15.
We report a 59-year-old woman who underwent thoracoscopic extirpation of the intrapulmonary cystic lymphangioma which was located in the subpleural space of the left upper lobe. A chest X-ray showed a solitary round nodule in the left pulmonary hilum. A computed tomography scan revealed a mass shadow at the interlobar region surrounding the interlobar pulmonary artery. A round nodule was recognized as low signal intensity on T1-weighted images by magnetic resonance imaging. There was biphasic signal intensity on T2-weighted images as well. Radiologically, we diagnosed this lesion as a benign cystic tumor in the lung. Thoracoscopic observation revealed a cystic lesion just beneath the visceral pleura of the upper lobe adjacent to the interlobular pulmonary artery. As this suggested a benign bronchogenic cyst, we performed extirpation of the cyst under thoracoscopy. After this operation, the cyst was diagnosed as an intrapulmonary cystic lymphangioma pathologically.  相似文献   
16.
A case of quadricuspid aortic valve with aortic regurgitation   总被引:2,自引:0,他引:2  
A 67-year-old man with grade 3 aortic valve regurgitation was found to have a quadricuspid aortic valve. The aortic valve consisted of 1 large, 2 intermediate and 1 small sized cusp. An accessory cusp located between the right and noncoronary cusps, and shaped like a hammock which sling by the fibrous strings originating from the both commissures to the aortic wall. Aortic valve replacement was successfully performed with a 23 mm St. Jude Medical prosthetic valve, and the patient is asymptomatic five months post-operatively. Histological examination of the resected cusps showed fibrous thickening and no rheumatic valvulitis or infective endocarditis.  相似文献   
17.
The changes in portal collaterals before and after Endoscopic Injection Sclerotherapy (EIS) for esophageal varices were studied by Single Photon Emission CT (SPECT). SPECT was performed for the intra-abdominal blood pool with 99mTc autologous red blood cells (RBC) in 17 patients with liver cirrhosis before and after EIS. Twenty mCi of 99mTc-RBC labeled by in vivo technique were administered intra-venously and tomographic imaging of the intra-abdominal vascular blood pool was performed as follows. For each subjects, 64 views were obtained over 360 degrees of elliptic rotation at 30 seconds per view. In 15 of 17 patients, blood pool images over coronary vein and/or short gastric vein area were clearly demonstrated on coronary images. In 9 of 15 patients, the pool of coronary vein or short gastric vein was disappeared or decreased after EIS. It is considered that intra-abdominal blood pool SPECT study is clinically useful for following up of hemodynamics of portal collaterals before and after EIS.  相似文献   
18.
19.
delta-Aminolevulinate dehydratase (ALA-D:porphobilinogen synthase, 5-aminolevulinate hydro-lyase, EC 4.2.1.24) activity was depressed markedly in red cells of rats exposed to 0.21 g/m3 styrene, a chemical widely used in commercial products. The depression was not restored in vitro after treatment with dithiothreitol and zinc. Consistent with this finding, radioimmunoassay of the enzyme protein demonstrated reduction in the enzyme concentration by styrene exposure. There was a good correlation between the decrease in enzyme activity and its concentration in the styrene-treated animals, suggesting that the depression of the enzyme activity was essentially due to the reduction in the enzyme content. Decrease in the enzyme content in bone marrow cells to almost the same extent as that in erythrocytes seems to indicate the decreased synthesis of ALA-D in the bone marrow. In vitro studies showed that styrene 7,8-oxide, the major intermediate of styrene metabolism, decreased the activity of purified ALA-D but that styrene, the parent compound itself, had no inhibitory effect. The activity and concentration of erythrocyte ALA-D in workers chronically exposed to styrene were also depressed significantly. These findings indicate that the styrene exposure-mediated decrease of ALA-D activity in erythrocytes was a reflection of reduction in the enzyme protein, which may have been the result of styrene 7,8-oxide action, and they suggest that a similar process may also be involved in the reduction of erythrocyte ALA-D in styrene-exposed workers.  相似文献   
20.
Multiple aortic aneurysms in Behçet’s disease were repaired with transluminaly placed endovascular stent grafts. Before deploying the stent graft device for permanent implantation for the saccular aneurysm located in the descending thoracic arota, from which feeding arteries for the spinal cord possibly branched, a retrievable stent graft was inserted and evoked spinal cord potential (ESP) were monitored in order to predict spinal cord ischemia. The original retrievable stent graft, constructed of a self-expandable Z-shaped stainless steel stent covered with e-PTFE, can be easily withdrawn into a 18 Fr. sheath after deployment. Blood flow into intercostal arteries branching from that part of the descending aorta where the permanent stent graft is planned to be implanted, is intercepted by the retrievable stent graft. A change of ESP during the temporary implantation of the device indicates that spinal cord ischemia would be caused by permanent implantation of the stent graft. In this case, no change of ESP was observed and the patient showed no postoperative paraplegia.The retrievable stent graft was useful for prediction of spinal cord ischemia before endoluminal stent graft repair of the descending aortic aneurysm. However, the device is not flexible enough to fit a severely tortuous aorta, therefore we are obliged to select patients to some extent. Further improvement of the device is required to make prediction of spinal cord ischemia with the retrievable stent graft possible in all cases.  相似文献   
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