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91.
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   
92.
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   
93.
94.
A primary hepatic carcinoid tumor arising in a 77-year-old woman is reported. The patient was admitted with a huge tumor in the right lobe of the liver and treated by an extended right lobectomy of the liver. Light microscopic findings showed that the tumor cells had small oval-shaped nuclei and eosinophilic cytoplasm with small granules forming trabecular, glandular, and rosette patterns. Immunohistochemically, tumor cells were stained positive with neuron-specific enolase and synaptophysin and were stained slightly positive with chromogranin and carcinoembryonic antigen. Careful examination before and after the operation revealed no other origin of the tumor. Based on the findings, the liver tumor was diagnosed as a primary carcinoid. The clinical features and diagnosis of this rare tumor are discussed in this report.  相似文献   
95.
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   
96.
Effects of 5-hydroxytryptamine (5-HT) on inhibitory synaptic transmission in the rat dorsolateral septal nucleus (DLSN) were examined by conventional intracellular and voltage-clamp recording methods. 5-HT (1-30 microM) depressed the monosynaptic fast IPSC evoked by local stimulation of the DLSN in the presence of DNQX, AP5 and CGP 55845A. CP 93129, a selective 5-HT1B receptor agonist, depressed the fast IPSC. The 5-HT-induced depression of the fast IPSC was attenuated by SB 216641, a selective antagonist for 5-HT1B receptors. 5-HT did not change the inward currents mediated by GABAA receptors, suggesting that 5-HT presynaptically inhibited the fast IPSC. 5-HT and CP 93129 depressed the frequency of miniature fast IPSPs (mIPSPs) without changing their amplitudes. Neither a selective protein kinase A inhibitor, H-89, nor a selective protein kinase C inhibitor, calphostin C, blocked the 5-HT-induced depression of the fast IPSC. N-Ethylmaleimide (NEM) blocked the 5-HT-induced depression of the evoked IPSC. These results suggest that activation of presynaptic 5-HT1B receptors depresses the release of GABA via a pertussis toxin (PTX)-sensitive G-protein in the rat DLSN.  相似文献   
97.
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   
98.
We report a rare case of neurofibromatosis type-2 (NF-2) associated with a chest wall schwannoma that was initially suspected of being a breast tumor. The patient was a 28-year-old female who was diagnosed as having NF-2 at 19 years old. At that time, she noticed a mass in the upper lateral region of her left breast but did not have it examined. The mass grew and became painful, and she was therefore referred to our department. Results of the initial examination indicated the possibility of a breast tumor, but a diagnosis of extramammary tumor of the major pectoralis major muscle was made on the basis of the results of ultrasonography and 3-dimensional computed tomography (3D-CT). An endoscope-assisted extirpation of the tumor was performed. Histologically, the tumor was an Antoni type A and B neurilemoma and was diagnosed as a schwannoma.  相似文献   
99.
The ethyl acetate soluble fraction of a MeOH extract of the dried stems and roots of Capsicum annum gave 10 new sesquiterpenoids (1-10) and nine known compounds. The structures of the new compounds were elucidated on the basis of spectroscopic evidence. The isolated new compounds were evaluated for their cytotoxic activities.  相似文献   
100.
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