Le CAP (Controlled attenuation parameter), un indicateur de risque et de sévérité du syndrome métabolique ?

ObjectivesThe aim of this study is to investigate the relationship between CAP (Controlled Attenuation Parameter) values and the different components of the metabolic syndrome.Materials and methodsThis is a cross-sectional study including all patients over 18 years of age with chronic liver disease who were referred to our center for a non-invasive assessment of liver fibrosis. The measurement of hepatic elasticity and CAP was carried out concomitantly using the M or XL probe of Fibroscan® by trained operators.ResultsThe prevalence of metabolic syndrome in patients with CAP ≥ 238 dB/m was higher than in patients with CAP < 238 dB/m, and significantly increased with the severity of hepatic steatosis (p < 0.001). CAP values were higher in patients with metabolic syndrome and significantly increased with the increase in the number of metabolic syndrome components (p < 0.001). In univariate analysis, there was a statistically significant positive linear relationship between CAP values and components of metabolic syndrome except for blood glucose and HDLc level. In multivariate analysis, only waist circumference and triglycerides level were significantly related to CAP values.ConclusionThis study shows that there is a significant correlation between CAP and the different components of the metabolic syndrome. CAP could be an indicator of risk and severity of metabolic syndrome.     

The effect of reconstruction and acquisition parameters for GRAPPA‐based parallel imaging on the image quality

Parallel imaging based on generalized autocalibrating partially parallel acquisitions is widely used in the clinical routine. To date, no detailed analysis has been presented describing the dependence of the image quality on the reconstruction and acquisition parameters such as the number of autocalibration signal (ACS) lines N_ACS, the reconstruction kernel size (b_x × b_y), and the undersampling factor R. To evaluate their influence on the performance of generalized autocalibrating partially parallel acquisitions, two phantom data sets acquired with 12‐channel and 32‐channel receive coils and three in vivo measurements were analyzed. Reconstruction parameters were systematically varied between R = 2–4, N_ACS = 4–64, b_x = 1–9, and b_y = 2–10 to characterize their influence on image quality and noise. A main aspect of the analysis was to optimize the parameter set with respect to the effectively achieved net image acceleration. Selecting the undersampling factor R as small as possible for a given net acceleration yielded the best result in a clear majority of cases. For all data sets and coil geometries, the optimal kernel sizes and number of ACS lines were similar for a chosen undersampling factor R. In summary, the number of ACS lines should not be chosen below N_ACS = 10–16. A robust choice for the kernel size was b_x = 9 and b_y = 2–4. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.     

Elucidated lipid structures of various human stratum corneum investigated by electron paramagnetic resonance spectroscopy

Background: Electron paramagnetic resonance (EPR) in conjunction with a slow‐tumbling simulation is useful for defining stratum corneum (SC) lipid structure. The objectives of this investigation were to evaluate and elucidate the lipid structure of various human SC as a function of the depth. Methods: The SC from mid‐volar forearms of human volunteers and a cadaver was stripped consecutively from one to three times using a glass plate coated with a cyanoacrylate resin. Spin probes were used to monitor SC ordering. EPR spectra were analyzed by an EPR slow‐tumbling simulation. Keratin solution from human epidermis was mixed with 5‐doxylstearic acid (5‐DSA) aqueous solution. Results: EPR analyses of 5‐DSA and CHL probes showed immobilized and mobile spectra, respectively. The simulation for 5‐DSA spectra showed differences in ordering values of the SC as a function of depth. EPR of keratin/5‐DSA showed mobile spectral pattern. In addition, EPR of CHL showed a weak and a broad signal. Conclusions: The keratin/5‐DSA results imply that the most likely location of 5‐DSA probe is in SC lipid. CHL probe may not easily permeate the SC. The EPR results along with the simulation analysis provide elucidated SC lipid structure.     

乳腺癌针吸细胞形态定量的人工神经网络诊断模型的建立及应用研究

目的 建立乳腺癌针吸细胞形态定量参数的人工神经网络诊断模型，并验证其在辅助FNA诊断乳腺癌的价值。方法 利用MPIAS-2000系统对60例乳腺癌及30例乳腺良性病变的针吸细胞学涂片进行形态定量测定，对获得的29项形态参数进行人工神经网络建模分析，并用盲法对其鉴别诊断能力进行评价。结果 所建立的网络模型经过14次训练后即可达到误差要求，诊断模型对乳腺癌及乳腺良性病变的诊断正确率为100％，其特异性和敏感性均为100％。结论 乳腺良恶性病变的针吸细胞学涂片进行ANN分析所建立的诊断模型，对乳腺癌及良性病病变的鉴别诊断具有较高的应用价值，为辅助针吸细胞学诊断乳腺良恶性病变提供了新的思路。     

头孢唑肟钠生产工艺及条件的研究

目的:对头孢唑肟钠生产过程进行研究。方法:以粗品7-氨基-3-烷基头孢烷酸和AE活性酯为原料合成头孢唑肟酸,再与无水碳酸钠反应制得头孢唑肟钠;同时研究反应时间、乙醇用量和滴加时间、无水碳酸钠的用量以及pH值对产品质量的影响。结果:反应过程完全可以实现,合成头孢唑肟钠的适宜工艺参数为反应时间1.5h,乙醇滴加速度400mL.h-1,反应温度30℃以下,乙醇与头孢唑肟酸用量比30mL∶1g,无水碳酸钠与头孢唑肟酸的质量比0.15∶1.00,溶液pH值6.9±0.1。结论:该工艺切实可行,为头孢唑肟钠工业化生产提供了可靠的依据。     

带形状参数的指数均匀B样条模型

本文给出了k(k≥2)阶带形状参数指数多项式的均匀B样条模型.该类模型具有很多与B样条模型相同的性质,并且具有一个可调节的形状参数.由该模型构造的曲线,通过改变形状参数的取值,可以调整曲线接近其控制多边形的程度.该模型可以应用于CAD/CAM领域,作为几何造型一种新的有效模型.     

浅谈医用显示器与普通显示器的区别

本文对医用显示器与普通显示器在参数上的区别作了对比，为医院选购配置显示器提供参考。     

浅析污水厂污泥厌氧消化成分及其变化过程

阐述了污水处理厂污泥厌氧消化过程中各种成分的变化过程及反应参数对其的影响.     

多层螺旋（MSCT）血管造影技术使用价值的探讨

搜集了2006年3月至12月568例血管成像,对正常血管解剖及靶血管病变的表现进行影像分析。结果表明：CT血管造影正确有效地显示血管解剖及血管病变的成功率达98%以上。多层螺旋CT血管造影术对于怀疑有血管性疾病,特别是主动脉疾病的患者,是一种安全、准确、无创伤的检查方法。     

提高CT图像质量的对策

本文在分析我院CT机三年的性能参数计量检定结果的基础上,介绍影响CT成像质量的因素及相应控制对策。