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1.
After removal of intraductal stones, a 10‐Fr or 7‐Fr pancreatic stent was placed in 16 patients with upstream ductal dilation proximal to a stricture of the main pancreatic duct. Stents were removed after a mean duration of 52.5 days. Nine patients underwent repeated stenting. About one year after removal of the initial stent, when the remaining upstream ductal dilation was found on follow‐up pancreatograms, the next stent was replaced. Repeated stenting improved outflow of pancreatic juice more effectively than one‐time stenting. Correlation between long‐term pain relief without recurrence of intraductal stones and reduction of duct diameter was also shown. Stent occlusion was observed in 14 of 30 stents. Stent occlusion was frequently associated with recurrence of pancreatitis and intraductal stones, and was also associated with morphologic changes in the pancreatic ductal system. Although there were no significant differences between stent patency of the initial stents and that of the next stents, stent patency of 10‐Fr stents was superior to that of 7‐Fr stents. 10‐Fr stents should be removed within 8 weeks and 7‐Fr stents should be removed within 4 weeks for the prevention of stent occlusion. Repeated stenting with short‐term stenting is therefore considered a safe and effective protocol of endoscopic pancreatic stenting.  相似文献   
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The placental transport mechanism of glutathione (GSH) was investigated using microvillous membrane vesicles prepared from human term placenta. Using (3H-glycine)-labeled-GSH, it was clarified that GSH in the extravesicular compartment of placental microvillous membranes was rapidly degraded by gamma-GTP (gamma-glutamyltranspeptidase) and resulting amino acid, and 3H-labeled-glycine was actively transported via a sodium cotransport system. AT-125 treated microvillous membrane vesicles almost entirely lost its gamma-GTP activity, and showed intact GSH transport. Using AT-125 treated microvillous membrane vesicles, it was revealed that GSH was transported across the microvillous membrane as an anion via a membrane potential-dependent mechanism. These results indicated that gamma-GTP which existed in microvillous membrane played a role in GSH metabolism and that intracellular GSH was translocated out of the syncythiotrophoblast cell into the maternal blood space via a specific carrier in microvillous membrane because the GSH concentration was higher in intracellular than extracellular and extracellular membrane potential was positively charged.  相似文献   
4.
A 32-year-old man had been suffering from dyspnea on exertion and stridor, which were due to stenosis of the left main bronchus as a complication of bronchial tuberculosis. A three-connection stent, 1.2 cm in diameter and 4.5 cm in length was placed at the site of the bronchial stenosis. Dyspnea disappeared 2 days after the procedure, and the pulmonary function 3 weeks later showed considerable improvements in %FVC, FEV1 and MMF.  相似文献   
5.
We performed myocardial revascularization with bilateral internal mammary arteries in eight children for coronary artery complications consequent to Kawasaki disease. Subjects included seven boys and one girl, ranging in age from 3 to 13 years (mean age, 8.3 +/- 3.4 years). The body surface area ranged from 0.65 to 1.65 m2 (average, 1.08 +/- 0.35 m2). Three patients had a previous myocardial infarction. The right internal mammary artery was anastomosed to the right coronary artery and the left internal mammary artery was sutured to the left anterior descending artery in all patients. The patients received an average of 2.4 grafts. Magnifying loupes of 3.5 X were used for anastomosis with 8-0 monofilament polypropylene sutures. Subjects were followed up from 12 to 38 months (23 +/- 10.8 months) after operation. All were doing well with no recurrence of angina, and body development was normal, including the sternum and thorax according to chest x-ray films and computed tomography of the chest. Patency of the bilateral internal mammary arteries was 100% in the early (within 1 month) postoperative period and remained so in the late (over 1 year) postoperative period. Anastomotic junctions between the internal mammary artery and the coronary artery developed well angiographically in the late postoperative period. The internal mammary artery is the graft of choice for pediatric myocardial revascularization because of its excellent long-term patency and growth potential. Bilateral internal mammary arteries should be used whenever indicated, and the use of bilateral internal mammary arteries did not adversely influence chest wall development in the children.  相似文献   
6.
Binswanger’s disease is pathologically characterized by a combination of diffuse cerebrovascular white matter lesions and lacunar infarcts in the basal ganglia and white matter. Although a blood-brain barrier (BBB) dysfunction has been implicated in the pathogenesis of these white matter (WM) lesions, few authors have addressed this problem. In the present study, we describe BBB dysfunction and its regional differences in the brains of Binswanger’s disease patients. Twelve brains from Binswanger’s disease patients (group III) were examined and compared with those from five patients with non-neurological disease (group I) and five cortical infarct patients without significant WM lesions (group II). Immunohistochemistry was performed for glial fibrillary acidic protein and vimentin as astroglial cell markers, and for immunoglobulins, complements and fibrinogen as extravasated serum protein markers. The grading scores for IgG extravasation were significantly higher in group III as compared to group I, in both the periventricular WM and the subcortical WM (P < 0.01). In group III, the scores in the periventricular WM and subcortical WM were significantly higher than in the subcortical U fibers and cerebral cortex (P < 0.01 for the periventricular WM; P < 0.001 for the subcortical WM), respectively. Clasmatodendritic astroglia, which had swollen cell bodies and large cytoplasmic vacuoles with disintegrated processes, incorporated the serum components IgG, IgM, C3d, C1q and fibrinogen, both in the periventricular WM and subcortical WM in 5 out of 12 (42%) Binswanger’s disease brains. These results indicate that WM lesions in Binswanger’s disease are accompanied by BBB dysfunction, although it remains uncertain whether BBB dysfunction is secondary to either chronic cerebral ischemia or arterial hypertension. Received: 25 April 1997 / Revised, accepted: 21 July 1997  相似文献   
7.
To elucidate the role of glutathione (GSH) on placental amino acid transport, we investigated L-lysine transport using microvillous membrane vesicles prepared from full term human placenta. 1. The transport of L-lysine into microvillous membrane vesicles was not affected by glutathione. 2. The transport of L-lysine into microvillous membrane vesicles was inhibited by inorganic mercury (Hg2+), and 0.1mM Hg2+ inhibited 34% of this transport and 1mM Hg2+ inhibited 50%. 3. The transport of L-lysine inhibited by Hg2+ was almost completely restored when glutathione was added simultaneously. These results indicated that glutathione defended the inhibitory action of inorganic mercury on L-lysine transport across microvillous membrane.  相似文献   
8.
Achieving coverage after digital injury is crucial, because simple skin defects can expose essential structures such as tendons or bones. This is particularly true on the dorsal surfaces of the digits, where the skin provides the only protection for the tendons. However, longitudinal skin defects of the digit have not been specifically identified in the literature and there have been few reports focusing on longitudinal dorsal skin defects. Here we report on the use of a bipedicle flap for reconstruction of complex longitudinal dorsal tissue defects of the digits, including those associated with tendon or bone damage.  相似文献   
9.
Two Puralpha-binding proteins (PurBPs) were found in nuclear extract from mouse brain during P4-P10 by the overlay assay. At P14, they were decreased significantly in nuclear extract and increased in the S3 fraction, indicating their dynamic translocation during development. Western blot analysis also demonstrated concomitant translocation of Puralpha with the PurBPs during P7-P14, when neuronal circuit proceeds. Immunocytochemical study with cultured hippocampal neurons from rat E18 confirmed that nuclear Puralpha was translocated to cytoplasm after plating for 7-14 days. These results suggest that spatiotemporal translocation of Puralpha with the PurBPs from nuclei to cytoplasm has a crucial role in neuronal development.  相似文献   
10.
Cell sheet engineering: recreating tissues without biodegradable scaffolds   总被引:6,自引:0,他引:6  
Yang J  Yamato M  Kohno C  Nishimoto A  Sekine H  Fukai F  Okano T 《Biomaterials》2005,26(33):6415-6422
While tissue engineering has long been thought to possess enormous potential, conventional applications using biodegradable scaffolds have limited the field's progress, demonstrating a need for new methods. We have previously developed cell sheet engineering using temperature-responsive culture dishes in order to avoid traditional tissue engineering approaches, and their related shortcomings. Using temperature-responsive dishes, cultured cells can be harvested as intact sheets by simple temperature changes, thereby avoiding the use of proteolytic enzymes. Cell sheet engineering therefore allows for tissue regeneration by either direct transplantation of cell sheets to host tissues or the creation of three-dimensional structures via the layering of individual cell sheets. By avoiding the use of any additional materials such as carrier substrates or scaffolds, the complications associated with traditional tissue engineering approaches such as host inflammatory responses to implanted polymer materials, can be avoided. Cell sheet engineering thus presents several significant advantages and can overcome many of the problems that have previously restricted tissue engineering with biodegradable scaffolds.  相似文献   
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