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A number of lectins were assessed for their ability to bind to glycoproteins in the surface membrane of Schistosoma mansoni. The membrane polypeptides were separated by SDS-PAGE and the glycoproteins visualised by incubating the gel with radio-iodinated lectin followed by autoradiography. Most of the individual lectins bound to a variety of glycoproteins but peanut agglutinin and Dolichos biflorus agglutinin bound preferentially to a single glycoprotein of apparent molecular weight 170 000. This glycoprotein was subsequently shown to be exposed at the surface of the parasite and localised at the tubercles. 相似文献
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Amirhesam Amerinatanzi Rodney Summers Kaveh Ahmadi Vijay K. Goel Timothy E. Hewett Edward Nyman 《The Knee》2017,24(2):207-216
Background
The proximal tibia is geometrically complex, asymmetrical, and variable, is heavily implicated in arthrokinematics of the knee joint, and thus a contributor to knee pathologies such as non-contact anterior cruciate ligament injury. Medial, lateral, and coronal tibial slopes are anatomic parameters that may increase predisposition to knee injuries, but the extent to which each contributes has yet to be fully realized. Previously, two-dimensional methods have quantified tibial slopes, but more reliable 3D methods may prove advantageous.Aims
(1) to explore the reliability of two-dimensional methods, (2) to introduce a novel three-dimensional measurement approach, and (3) to compare data derived from traditional and novel methods.Methods
Medial, lateral, and coronal tibial slope geometry from both knees (left and right) of one subject were obtained via magnetic resonance images and measured by four trained observers from two-dimensional views. The process was repeated via three-dimensional approaches and data evaluated for intra- and inter-rater reliability.Results
The conventional method presented a weaker Intraclass Correlation Coefficient (ICC) for the measured slopes (ranging from 0.43 to 0.81) while the resultant ICC for the proposed method indicated greater reliability (ranging from 0.84 to 0.97). Statistical analysis supported the novel approach for production of more reliable and repeatable results for tibial slopes.Conclusions
The novel three-dimensional method for calculating tibial plateau slope may be more reliable than previously established methods and may be applicable in assessment of susceptibility to osteoarthritis, as part of anterior cruciate ligament injury risk assessment, and in total knee implant design. 相似文献23.
Dominik Siallagan Yue-Hin Loke Laura Olivieri Justin Opfermann Chin Siang Ong Diane de Zélicourt Anastasios Petrou Marianne Schmid Daners Vartan Kurtcuoglu Mirko Meboldt Kevin Nelson Luca Vricella Jed Johnson Narutoshi Hibino Axel Krieger 《The Journal of thoracic and cardiovascular surgery》2018,155(4):1734-1742
Background
Despite advances in the Fontan procedure, there is an unmet clinical need for patient-specific graft designs that are optimized for variations in patient anatomy. The objective of this study is to design and produce patient-specific Fontan geometries, with the goal of improving hepatic flow distribution (HFD) and reducing power loss (Ploss), and manufacturing these designs by electrospinning.Methods
Cardiac magnetic resonance imaging data from patients who previously underwent a Fontan procedure (n = 2) was used to create 3-dimensional models of their native Fontan geometry using standard image segmentation and geometry reconstruction software. For each patient, alternative designs were explored in silico, including tube-shaped and bifurcated conduits, and their performance in terms of Ploss and HFD probed by computational fluid dynamic (CFD) simulations. The best-performing options were then fabricated using electrospinning.Results
CFD simulations showed that the bifurcated conduit improved HFD between the left and right pulmonary arteries, whereas both types of conduits reduced Ploss. In vitro testing with a flow-loop chamber supported the CFD results. The proposed designs were then successfully electrospun into tissue-engineered vascular grafts.Conclusions
Our unique virtual cardiac surgery approach has the potential to improve the quality of surgery by manufacturing patient-specific designs before surgery, that are also optimized with balanced HFD and minimal Ploss, based on refinement of commercially available options for image segmentation, computer-aided design, and flow simulations. 相似文献24.
Schneider AM Simson PE Atapattu RK Kirby LG 《Pharmacology, biochemistry, and behavior》2011,98(4):539-543
Previous work has shown that the effect of opioid-receptor blockade on memory modulation is critically dependent upon the intensity of stress. The current study determined the effect of adrenergic-receptor blockade on memory modulation under varied levels of stress and then compared the effect of adrenergic-receptor blockade under intense stress to that of a) opioid-receptor blockade and b) concurrent opioid- and adrenergic-receptor blockade. In the first experiment, the β-adrenergic-receptor blocker propranolol impaired retention in the passive-avoidance procedure when administered immediately after exposure to intense stress (passive-avoidance training followed by swim stress) but not mild stress (passive-avoidance training alone). In the second experiment, while separate administration of either propranolol or the opioid-receptor blocker naloxone immediately after exposure to intense stress impaired retention, the combined administration of propranolol and naloxone failed to do so. These findings demonstrate that the effect of β-adrenergic-receptor blockade or opioid-receptor blockade on memory modulation in the passive-avoidance procedure is dependent upon the intensity of stress, and suggest that concurrent inactivation of endogenous adrenergic- and opioid-based memory modulation systems under stressful conditions is protective of memory. 相似文献
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目的把STL文件格式应用到医学模型的存储,通过设定三维医学模型的不同部分的颜色以提升模型的三维可视化效果。方法针对STL文件格式表示人体解剖模型色彩单一的问题,对STL文件内容进行了修改:在三角形几何位置信息中加入了颜色信息,通过颜色信息来区分人体解剖模型不同组成部分之间的关系。在三维医学模型不同组成部分边界划分过程中,通过建立二维屏幕坐标与三维模型坐标之间的关系,把屏幕上划分的边界映射到三维模型上,并应用连接算法保证三维边界的封闭性,最后采用类种子填充算法,实现边界内区域的颜色填充。结果通过颜色区分后的医学模型能够更准确地描述模型的不同组成部分,有更好的三维可视化效果。结论边界划分与区域填充算法能够很好地实现三维模型的区域着色,经过改进后的STL文件能够有效地存储彩色的三维医学模型。 相似文献