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71.
72.
Abstract

Neovascularization, the development of a new microvasculature, has an important role in physiological and pathological processes. The vascular changes in the brain can be easily detected because the proliferation of endothelial cells in its vascular structure is quite small, and so constitutes a good model for neovascularization studies. In the present investigation, to induce intracerebral neovascularization, we implanted collagen, Interleukin-l alpha (IL-lα) and glicosaminoglycan into the brain ofpigs, in order to test the hypothesis that IL-l α, collagen and glicosaminoglycan play a pivotal. role in the process of neovascularization. Both pure collagen and collagen combined with IL-l a induced neovascularization according to light-electron microscopic findings and values of enzymes' activities. In particular, collagen combined with IL-lα synergically affected the increase of neovascularization. However, glicosarrinoglycan did not affect it significantly. Although the results of this study provided us with some interesting data indicating the beneficial effects of collagen combined with IL-1α on neovascularization, further studies should be done to study the short term effect of these biochemical substances. [Neural Res 1998; 20: 513-525]  相似文献   
73.
The aim of this investigation was to compare the traditional method of manual cephalometric tracing with four different computerized tracing programs, where the lateral cephalograms were scanned at 300 dpi and digitized onscreen. Thirty randomly selected cephalometric radiographs were used in this study. Four programs Dolphin Imaging, Vistadent, Nemoceph, and Quick Ceph were evaluated. Three dental, 11 skeletal, and 1 soft tissue parameters were measured that consisted of 5 linear and 10 angular measurements. Statistical analysis was carried out using multivariate analysis of variance and Box's and Levene's tests. No statistically significant difference was found between manual tracing and the computerized tracing programs. The measurements obtained with the cephalometric analysis programs used in the study were reliable.  相似文献   
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In low‐grade glioma, metastasis is rarely seen. Few cases of leptomeningeal dissemination have been reported in children. Vertebral bone metastasis has not been reported so far. Herein is described the case of a pediatric patient with the diagnosis of pilocytic astrocytoma, and leptomeningeal dissemination detected at the time of diagnosis, who then received radiotherapy and chemotherapy upon development of vertebral bone metastasis during treatment.  相似文献   
76.
Thymic cysts are divided into two groups as unilocular and multilocular cysts. Cystic wall is generally lined with squamous, transitional, cuboidal, or columnar epithelium. Unilocular cysts that are lined with ciliated respiratory epithelium are extremely rare, and there are only two reports in the literature. In this paper, we present a case, which had concurrent unilocular thymic cyst lined with ciliated respiratory epithelium and pericardial diverticulum.  相似文献   
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PTEN is a tumor suppressor gene that is frequently mutated in type I endometrioid endometrial carcinomas (EECs), and is involved in the control of cell proliferation, differentiation, and apoptosis. In this study, we aimed to assess the relationship between PTEN expression and estrogen, progesterone receptors (PRs), other apoptosis-related proteins, such as bcl-2 and bax, and apoptotic index (AI) in EEC, its precursor lesion hyperplasia, and cyclical endometrium. We also evaluated the relationship between PTEN expression and clinicopathologic parameters. PTEN, estrogen receptor (ER), PR, and bcl-2 and bax expressions were evaluated immunohistochemically, and AI was evaluated in hematoxylin and eosin (HE)-stained slides in 23 cyclical and 37 hyperplastic endometria and in 35 EECs. PTEN expression was higher in cyclical endometrium than in the carcinomas (p<0.05). The PTEN expression level was significantly higher in non-atypical hyperplasias than in EEC, but there were no differences between atypical complex hyperplasia (ACH) and EEC and between hyperplasias. In the carcinomas, there was a negative correlation between grade and PTEN expression (r=-0.338, p=0.047). In conclusion, we presume that PTEN is involved in the early phases of endometrial tumorigenesis, and it can be speculated that decreased PTEN expression with loss of differentiation in carcinoma can contribute to the emergence of tumors with a more aggressive phenotype.  相似文献   
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ABSTRACT: Reconstruction of columella presents certain difficulties and includes reconstruction of the cartilaginous strut and the overlying skin to obtain good results. We conducted a retrospective clinical review of 38 patients presenting with congenital and acquired columellar defects. Anatomic characteristics to be considered were defined and a classification method is proposed to more fully describe columellar defects. The columellar defects of the patients were classified into three groups as follows: type I, skin defect of columella and absence of medial crura of lower lateral cartilage; type II, type II + partial absence of caudal part of septal cartilage; and type III, complex defect of columella accompanying with the other nasal subunit defects. The patients chosen in this study were designed to describe a common approach for the choice of the reconstruction method that provides excellent aesthetic result while minimizing the extent of the surgery and maximizing patient acceptance.  相似文献   
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