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The purpose of this study was to investigate the effect of temporary hemiepiphyseal stapling on the bone geometry and proliferative activity of the physis in immature rabbits. Proximal medial epiphyseal stapling of the right tibia was performed in 46 6-week-old New Zealand white rabbits. The rabbits were assigned randomly into two groups. In group 1, the staples were inserted extraperiosteally and the rabbits were killed at the end of 3 weeks. In group 2, the staples were fixed subperiosteally (group IIA) or extraperiosteally (group IIB), the staples were removed at the end of 3 weeks, and the rabbits were killed at the end of 6 weeks. The articular line-diaphysis angle (ALDA) was significantly increased with 3 weeks of stapling. After the removal of staples, while ALDA continued to worsen in group IIA, it improved in group IIB. Bone was observed to bridge the physis in group IIA. However, the proliferative activity of the physis continued. Temporary hemiepiphyseal stapling is a safe and effective method for control of physeal growth of long bones before skeletal maturity. However, it is of paramount importance not to disturb the periosteum during stapling.  相似文献   
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The aim is to examine histopathological changes and expression of epidermal growth factor receptor (EGFR) in tracheal epithelia caused by application of topical mitomycin-C (MMC) in rabbit model after the tracheotomy procedure. The conventional tracheotomy was performed in 16 rabbits. They were randomly divided into two equal groups. The first group was applied MMC at a concentration of 0.4 mg/ml around tracheotomy for 5 min, and the other group was not taken a treatment as a control. The animals were sacrificed at the end of 4 weeks. Their tracheas were evaluated with H&E and Masson's trichrome histochemically, and with antiepidermal growth factor receptor immunohistochemically. Results showed that there was no significant difference between MMC and control group for inflammatory cells (P=0.09). The numbers of fibroblasts and subepithelial tissue thickness in the group exposed to MMC were significantly lower than the control group (P<0.05). In contrast, the percentage of EGFR in the application of MMC group was significantly higher than the control group (P<0.05). The application of topical MMC on airway epithelia after tracheotomy showed significant elevation in the levels of epithelial EGFR expression compared to controls in a rabbit model. The activation of epithelial EGFR may facilitate epithelial healing, but further studies are needed to assess the effect of topical MMC on respiratory epithelia.  相似文献   
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PURPOSE: To evaluate the normal configuration and size of the third ventricle in second and third trimester fetuses in a normal population, and to compare our values with those of previously published studies. MATERIAL AND METHODS: Evaluation of fetal third ventricular width and configuration was obtained by antenatal ultrasonography in 474 fetuses with gestational age between 12 weeks and term (mean 28 weeks). Percentiles for third ventricle width were estimated by combining separate fractional polynominal regression models fitted to the mean and standard deviation, assuming that the measurements had a normal distribution at each gestational age. Appearance of the third ventricle was correlated with each gestational age. RESULTS: The third ventricle could be visualized in 471 (99%) of 474 fetuses. The 97th percentile of the third ventricle in preterm fetuses was measured as 3.6 mm in size. The third ventricle was seen as a single echogenic line in 153 (32.4%) of 474 fetuses. Two-hundred-and-ninety-nine (61.5%) of all fetuses had parallel echogenic lines outlining a fluid-filled lumen. V-shaped third ventricular configuration was seen in only 28 (5.9%) of the fetuses. From 24 weeks to term, parallel echogenic lines were the most commonly (83.7% to 79.6%) encountered configuration for the third ventricle. CONCLUSION: The 97th percentile of the third ventricle in preterm fetuses was measured as 3.6 mm in size. In the early second trimester, 77% of the fetuses had a single echogenic line appearance on ultrasonography. As the brain and ventricular structures mature, a parallel echogenic line becomes the prominent ultrasonography appearance (>80% of fetuses) in third trimester healthy fetuses.  相似文献   
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This study aimed to compare connective tissue components within the uterine ligaments histopathologically in women with and without pelvic relaxation. The tissue samples obtained from the histopathologic specimens of 24 patients with uterine descensus who underwent vaginal hysterectomy and from twenty-one patients with no pelvic relaxation, in whom total abdominal hysterectomies were performed for benign reasons, were used as the study and control groups, respectively. From each hysterectomy material, samples for histological examination were taken from the vaginal fascia and from the cardinal, the uterosacral and the round ligaments (4 samples for each patient). The amount of collagen, cellularity and elastic fibers within the connective tissue were evaluated and scored by the co-author pathologist. Mann-Whitney U and Student t tests were used for the statistical analysis. The patients with pelvic relaxation had significantly higher scores of collagen and fewer scores of cellularity within the connective tissue samples, compared with the ones without relaxation (p<0.01, p<0.01). It was concluded that decreased fibroblasts and increased collagen content might be the key factors associated with pelvic support disorders. Received: 8 January 2001 / Accepted: 19 March 2001  相似文献   
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Turner's syndrome is associated with autoimmune disorders. Autoimmune endocrinopathy in Turner's syndrome seems to be limited to autoimmune thyroiditis. A small number of patients with Turner's syndrome has also been associated with celiac disease, inflammatory bowel disease and juvenile rheumatoid arthritis. Type 1 diabetes mellitus in Turner's syndrome has been rarely reported. We present here the youngest patient with Turner's syndrome who developed type 1 diabetes mellitus. At the age of 3.5 years she was hospitalized with diabetic ketoacidosis. Anti-islet cell and anti-insulin antibodies were positive and C-peptide level was low. When she was investigated for recurrent urinary tract infections, horseshoe kidney was detected by ultrasonography. Karyotype analysis revealed 45,XO. She has been followed for 2 years with an insulin dose of 0.9 U/kg per day. The prevalence of type 1 diabetes mellitus associated with Turner's syndrome is still unknown.  相似文献   
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OBJECTIVE: In trying to answer the question about the controversial use of sequential grafts, we determined the mid-term angiographic outcome of patients in whom coronary artery bypass was performed with different types of vein grafts. METHODS: A total of 1034 coronary anastomoses on 724 saphenous vein grafts (SVGs) (apart from 497 left internal mammarian artery (LIMA) anastomoses) were assessed in 509 patients in an average of 55.4 +/- 17.6 months after coronary artery bypass grafting. RESULTS: The patency rates of sequential conduits were markedly higher than those of individual ones (86.6% vs 69.6%, p = 0.0001). Also, the anastomoses on the sequential conduits had better patency rates (80.6% vs 69.6%, p = 0.0001). This difference was even more pronounced in coronary arteries of poor quality/small (< 1.5 mm) diameter (68.9% vs 51.6%) for the sequential and individual grafts, respectively (p = 0.03). Also, the patency of the entire sequential conduit was lower when most distally located anastomosis was of poor runoff (45.2%). CONCLUSIONS: The patency of a sequential vein conduit is generally superior than that of an individual one, especially for poor runoff coronary vessels, provided that the most distally located anastomosis is performed on a good coronary artery in terms of quality and diameter. Using a minimal length of SVG is another advantage. However, failure of a single sequential conduit jeopardizes all of the anastomoses along that graft segment. Besides, being technically more demanding, technical expertise in performing a sequential anastomosis is probably among the important predictors of patency.  相似文献   
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