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991.
目的编制出合理的软件程序,对颈动脉系列截面图进行三维超声重建.方法用自行研制的机械臂及软件系统采集颈动脉图像并进行数字化处理,再用计算机图形学方法重建出血管三维图像.结果应用三维图形库OpenGL绘制出具有真实感的三维血管表面图像并进行定量测定.结论该软件系统简单、合理、便于操作,可完成血管等距横断面图像的三维重建.  相似文献   
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Tetralogy of Fallot (TOF) is the most common complex congenital heart disease (CHD) of the cyanotic type. Studies on ventricular functions have received an increasing amount of attention as the development of diagnosis and treatment technology for CHD continues to advance. Reasonable options for imaging examination and accurate assessment of preoperative and postoperative left ventricular functions of TOF patients are important in improving the cure rate of TOF radical operation, therapeutic evaluation, and judgment prognosis. Therefore, with the aid of dual‐source computed tomography (DSCT), cardiac images with high temporal resolution and high definition, we measured the left ventricular time–volume curve using image data and calculating the left ventricular function parameters to conduct the preliminary evaluation on TOF patients. To comprehensively evaluate the cardiac function, the segmental ventricular wall function parameters were measured, and the measurement results were mapped to a bull's eye diagram to realize the standardization of segmental ventricular wall function evaluation. Finally, we introduced a new clustering method based on auto‐regression model parameters and combined this method with Euclidean distance measurements to establish an intelligent diagnosis of TOF. The results of this experiment show that the TOF evaluation and the intelligent diagnostic methods proposed in this article are feasible.  相似文献   
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Background There is a paucity of literature available as to the relationship between different levels of each metabolic syndrome (MetS) component and decreased GFR. In the present study, we aimed to demonstrate whether MetS always plays a critical role in decreased GFR. Methods A cross-sectional study was conducted between February 2010 and September 2012, with 75,468 adults enrolled undergoing measurements of blood pressure as well as tests of blood and urine samples. Univariate and multivariable logistic regression analyses were performed to estimate the odds ratio (OR) with 95% confidence intervals (CI), and the chi-square test was used for categorical variables and described as a percentage. Results Of the 75,468 participants, 350 (0.5%) subjects met criteria for the decreased GFR, with a mean age of 48.79?±?13.76?years. After adjustment for age, diastolic blood pressure and high-density lipoprotein were inversely related to decreased estimated glomerular filtration rate (eGFR) in multivariable analyses, with an OR (95% CI) of 0.57 (0.39–0.84) and 0.41 (0.24–0.72), respectively. The prevalence rate of CKD in critical group was 0.73% (154 of 21,127) and 0% (0 of 370) in noncritical group. In analysis stratified by the type of MetS components, the differences in noncritical group and the reference group were not statistically significant (χ2?=?1.349, p?>?0.05). Conclusions MetS does not always play a critical role in decreased GFR, with different levels of individual components of MetS exerting idiosyncratic effects in decreased eGFR. In fact, patients with abnormal body mass index, high triglycerides, and elevated fasting plasma glucose would not have impact on decreased GFR.  相似文献   
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Conclusions: The results indicate that the injury of the marginal mandibular branch improved the recovery of the buccal branch in a rat model.

Objective: The aim of this study was to investigate whether the injury or intactness of the marginal mandibular branch affects the regeneration of the facial nerve buccal branch in a rat model.

Methods: This experiment was conducted on 30 adult rats, which were randomly and equally divided into two groups. The buccal branch of the facial nerve was transected and reconstructed, with the marginal mandibular branch damaged (group A) or intact (group B). The vibrissae movement of rats was assessed since the 4th week after operation. At the 8th and 12th week, compound muscle action potentials (CMAPs) and morphological changes of injured buccal branches were evaluated.

Results: After the operation, vibrissae movement of rats was eliminated in group A, but it was similar to the health side in group B. CMAPs were recorded from regenerated buccal branches in group A since the 8th week, but no CMAPs could be recorded in group B at each time point. Additionally, the diameter of nerve fibers, the thickness of myelin sheath, and the density of regenerated fibers in group A were significantly larger than those in group B (p?相似文献   
997.
Donor‐specific alloantibodies (DSA) can cause acute antibody‐mediated rejection (AMR) in all solid organ allografts. However, long‐term outcome in patients with posttransplant DSA needs further study. We retrospectively evaluated prospectively collected paired serum, tissue, and data on 45 matched DSA? positive [DSA+; mean florescence intensity (MFI) ≥10 000] and ‐negative (DSA?) recipients of a primary liver‐only allograft from January 2000 to April 2009. Blinded histopathologic evaluation demonstrated that DSA+ versus DSA? patients were more likely to have subtle inflammation and unique patterns of fibrosis, despite normal or near‐normal liver function tests. Stepwise multivariable modeling developed a score (putatively named the chronic AMR [cAMR] score) that included interface activity, lobular inflammation, portal tract collagenization, portal venopathy, sinusoidal fibrosis, and hepatitis C virus status. The score was developed (c = 0.811) and cross‐validated (c = 0.704) to predict allograft failure. Two cutoffs were employed to optimize sensitivity and specificity (80% each); a value >27.5 predicted 50% 10‐year allograft failure. We propose chronic AMR as a potential new entity defined by (1) a high cAMR score, (2) DSA, and (3) elimination of other potential causes of a similar injury pattern. In conclusion, cAMR score calculation identified liver allograft recipients with DSA at highest risk for allograft loss, although independent validation is needed.
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