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81.
82.
Purpose: To examine changes in the reference segment luminal diameter after coronary angioplasty. Methods: Sixty-one patients with stable angina pectoris or old myocardial infarction were examined. Coronary angiograms were recorded before coronary angioplasty (pre-angioplasty) and immediately after (post-angioplasty), as well as 3 months after. Artery diameters were measured on cine-film using quantitative coronary angiographic analysis. Results: The diameters of the proximal segment not involved in the balloon inflation and segments in the other artery did not change significantly after angioplasty, but the reference segment diameter significantly decreased (4.7%). More than 10% luminal reduction was observed in seven patients (11%) and more than 5% reduction was observed in 25 patients (41%). More than 5% underestimation of the stenosis was observed in 22 patients (36%) when the post-angioplasty reference diameter was used as the reference diameter, compared with when the pre-angioplasty measurement was used and more than 10% underestimation was observed in five patients (8%). Conclusion: This study indicated that evaluation by percent diameter stenosis, with the reference diameter from immediately after angioplasty, overestimates the dilative effects of coronary angioplasty, and that it is thus better to evaluate the efficacy of angioplasty using the absolute diameter in addition to percent luminal stenosis.  相似文献   
83.
Recently, it was reported that an EMS (expandable metallic stent) was useful for treatment of colorectal obstruction. In our department, EMSs were used for seven patients with left-sided colonic obstruction with unresectable malignant disease. After these treatments with EMS, their symptoms were improved and they were able to intake food. Stomal formation was avoided except in one patient with severe soiling. In conclusion, EMS is thought to be useful for the improvement of quality of life in the patients with unresectable malignant colonic obstruction.  相似文献   
84.
Although studies have shown that early oral feeding after abdominal surgery is feasible, the optimal dietary schedule has not been established. This study was conducted prospectively to compare the clinical outcome of patient-controlled dietary schedule with that of conventional dietary schedule after gastric resection for early cancer. Patients in the patient-controlled diet (PC) group (n = 53) received a solid diet on demand; patients in the conventional regimen (CR) group (n = 50) received a solid diet from postoperative day (POD) 10. All patients underwent distal gastrectomy for early gastric cancer. A liquid diet was tolerated by the PC group on POD 2, and a solid diet was taken on POD 6 after gastrectomy, earlier than in the CR group. The postoperative hospital stay was 18.5 ± 5.9 days (10–40) in the PC group, versus 21.7 ± 8.8 days (14–57) in the CR group (p = 0.02). Patients in the PC group had a higher daily oral intake of calories on POD 10 than those in the CR group (p = 0.02). Changes in body weight and serum albumin during the postoperative period and after discharge, and the incidence of complications and variances from clinical pathways did not show significant differences between the two groups. The PC schedule was feasible after distal gastrectomy for early gastric cancer. It improved the clinical outcome, with a shorter postoperative hospital stay and a higher oral energy intake on early phase, compared with the CR schedule. Moreover, the PC approach was useful for establishing the optimal dietary schedule and improving the clinical pathway.  相似文献   
85.
BACKGROUND: It has been speculated that host macrophages contribute to rapid clearance of transplanted xenogeneic cells. To address such a possibility, phagocytotic and cytolytic activities of human macrophages toward xenogeneic porcine cells were evaluated in vitro in the absence of antibodies and complement factors. METHODS: Human peripheral monocyte-derived macrophages (P-macrophages) and reticulo-endothelial macrophages (RE-macrophages) were obtained from volunteers' peripheral blood and from the perfusion effluents of liver allografts for transplantation, respectively. 5-(and 6-) carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeled human autologous red blood cells (auto-RBCs), ABO-incompatible RBCs (incom-RBCs) and xenogeneic porcine RBCs (xeno-RBCs) were incubated with the human macrophages; subsequently, the macrophages that had phagocytosed the RBCs could be identified as CFSE positive cells by FCM analyses and confocal microscopy. Cytolytic activity was quantified by calculating levels of lactate dehydrogenase in each culture supernatant. RESULTS: Human RE-macrophages spontaneously phagocytosed and had a remarkable cytolytic activity toward xeno-RBCs, but not toward auto-RBCs or incom-RBCs. Elimination of alpha-galactosyl xenoantigen (alpha-Gal) epitopes on xeno-RBCs did not prevent phagocytotic or cytolytic activity of RE-macrophages. CONCLUSIONS: These findings indicate phagocytotic and cytolitic activities of human macrophages toward porcine cells are initiated by a factor other than alpha-Gal in a mechanism independent of antibody/complement opsonization.  相似文献   
86.
Osteogenic potential of primed periosteum graft in the rat calvarial model   总被引:3,自引:0,他引:3  
Repair of bone defects remains a major concern in plastic and maxillofacial surgery. Based on modern concepts of tissue engineering, periosteum has gained attention as a suitable osteogenic material. We tested the hypothesis that surgically released and immediately repositioned periosteum would exhibit high osteogenic capacity upon grafting in a rat calvarial defect. Seven days after periosteum was released from the tibia and immediately repositioned, the "primed periosteum graft" (PPG; n = 15) was placed into a critical-sized defect of rat calvaria and the process of bone formation was evaluated histologically, immunohistologically, and radiographically at 7, 14, and 21 days after grafting. Findings were compared with a nonprimed periosteal graft (NPG; n = 15).Endochondral ossification was observed in both the PPG and NPG. The PPG showed higher expression of proliferative cell nuclear antigen, bone morphogenetic protein, and vascular endothelial growth factor than the NPG. Three-dimensional radiographic examination revealed significantly increased bone formation in the PPG than in the NPG (P < 0.01). These findings suggested that surgical stimulation of the periosteum enhanced the osteogenic potential of periosteal cells. This method may be suitable for the clinical repair of bone defects.  相似文献   
87.
A total of 1,228,551 newborn babies, who were almost all of babies born in Osaka for 14 years (168 months), were screened for congenital primary hypothyroidism by an identical mass-screening program using the thyrotropin method, and 429 patients with hypothyroidism due to thyroid dysgenesis (dysgenetic hypothyroidism) were found. The occurrence of the patients in every month was not random but episodic and the incidence was higher in the late autumn (from October to December). These observations support a hypothesis that some environmental factors may cause this disorder overtime and the possibility of relation with intrauterine viral infection was discussed.  相似文献   
88.
89.
Vessel invasion is an important step in cartilage replacement that leads to bone formation, and vascular endothelial growth factor (VEGF) has been implicated as a key player in this process. Although grafted periosteum undergoes endochondral ossification, little is known about the role of VEGF in this process. In the current study the authors investigated by immunohistochemical, histochemical, and ultrastructural techniques the localization of VEGF during bone formation in periosteal grafts. At day 14 after grafting the tibias of Japanese white rabbits, periosteal cells in the grafted tissue had differentiated into chondrocytes to form cartilage. Some chondrocytes were immunopositive for VEGF expression, and subsequent vessel invasion occurred predominantly in these VEGF-positive areas. At day 45, the cartilage invaded by blood vessels had been replaced by newly formed bone. These findings suggest that VEGF is associated with the process of blood vessel invasion into cartilage before bone replacement in endochondral ossification from grafted periosteum.  相似文献   
90.
This study was performed to analyze postoperative courses and complications, retrospectively, following transplants from non-heart-beating donors and to examine the correlation between early graft function and clinical parameters. We experienced 11 cases of kidney transplants from non-heart-beating donors during the period from April 1995 to May 2003. Warm ischemic time was less than 30 min in all cases, and total ischemic time ranged from 8.4 hours to 27.9 hours. Rejection reactions occurred in seven cases, two of which were vascular rejections. Infectious disease complications included CMV in two cases, interstitial pneumonia in one case and fungal infection in one case. One patient died from interstitial pneumonia, and three patients had to be restarted on dialysis due to loss of function of the grafted kidney. The remaining seven patients all made full recoveries. All of the 16 patients who underwent living related kidney transplantations during the same period made full recoveries. Both the donor's gender and the latest creatinine level of the donor influenced the posttransplant dialysis period. The posttransplant dialysis period significantly influenced the creatinine level one month after transplant. These results suggest that patients who undergo kidney transplants from non-heart-beating donors have higher rates of complications than patients who undergo living related kidney transplantation. It is important that, in cases where the donor's creatinine level is high, especially when the donor is male, the kidney is carefully retrieved and transported to the recipent hospital to shorten the ischemic period as much as possible.  相似文献   
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