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61.
Gaetano Scala Paolo De Girolamo Mario Corona Gaetano Vincenzo Pelagalli 《Anatomical record (Hoboken, N.J. : 2007)》2002,266(1):58-68
The microvasculature of the water buffalo (Bubalus bubalis) epididymis was investigated using light (LM), scanning electron (SEM), and transmission electron (TEM) microscopy techniques. SEM analysis of the buffalo epididymis showed fenestrations that occupied ovoid inside the endothelium of the postcapillary venules located in the caput, corpus, and cauda. They varied in shape and dimension, but more importantly, they connected the venules of the blood vascular system to the capillaries of the peripheral lymphatic vascular system. Morphofunctional analysis of these connections suggests that the microvasculature of the buffalo epididymis plays a role in facilitating the circulation of biologically active substances, and the absorption and secretion processes necessary for the survival and maturation of spermatozoa. The lymphatic capillaries at the connection points formed a network of variously sized polygonal links. These capillaries then converged to form the precollector lymphatic vessels, which in turn converged with the larger vessels originating from the testis. It was further noted that in the capillary endothelium there were no fenestrations, and in the large veins there were many diverticula. These diverticula appear to play a role in the regulation of the seasonal variations of the blood reflux. In general, the microvascular architecture of the buffalo epididymis, particularly its connection to the lymphatic vascular system, appears to play an important role in the absorption and secretion processes of the epididymal epithelium. Anat Rec 266:58–68, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
62.
Dr. Y. Fukuoka M. Noshiro H. Shindo H. Minamitani M. Ishikawa 《Medical & biological engineering & computing》1997,35(1):33-39
The nonlinearity included in the PCO
2 control system in humans is evaluated using the degree of nonlinearity based on a difference of residuals. An autoregressive
moving average (ARMA) model and neural networks (linear and nonlinear) are employed to model the system, and three types of
network (Jordan, Elman and fully interconnected) are compared. As the Jordan-type linear network cannot approximate respiratory
data accurately, the other two types and the ARMA model are used for the evaluation of the nonlinearity. The results of the
evaluation indicate that the linear assumption for the PCO
2 control system is invalid for three subjects out of seven. In particular, strong nonlinearity was observed for two subjects. 相似文献
63.
Heinzerling L Frew AJ Bindslev-Jensen C Bonini S Bousquet J Bresciani M Carlsen KH van Cauwenberge P Darsow U Fokkens WJ Haahtela T van Hoecke H Jessberger B Kowalski ML Kopp T Lahoz CN Lodrup Carlsen KC Papadopoulos NG Ring J Schmid-Grendelmeier P Vignola AM Wöhrl S Zuberbier T 《Allergy》2005,60(10):1287-1300
Skin prick testing (SPT) is the standard method for diagnosing allergic sensitization but is to some extent performed differently in clinical centres across Europe. There would be advantages in harmonizing the standard panels of allergens used in different European countries, both for clinical purposes and for research, especially with increasing mobility within Europe and current trends in botany and agriculture. As well as improving diagnostic accuracy, this would allow better comparison of research findings in European allergy centres. We have compared the different SPT procedures operating in 29 allergy centres within the Global Allergy and Asthma European Network (GA(2)LEN). Standard SPT is performed similarly in all centres, e.g. using commercial extracts, evaluation after 15-20 min exposure with positive results defined as a wheal >3 mm diameter. The perennial allergens included in the standard SPT panel of inhalant allergens are largely similar (e.g. cat: pricked in all centres; dog: 26 of 29 centres and Dermatophagoides pteronyssinus: 28 of 29 centres) but the choice of pollen allergens vary considerably, reflecting different exposure and sensitization rates for regional inhalant allergens. This overview may serve as reference for the practising doctor and suggests a GA(2)LEN Pan-European core SPT panel. 相似文献
64.
65.
采用多分辨率分析和人工神经网络相结合的方法实现对心室晚电位的检测。首先利用多分辨率分解技术提取高分辨率心电信号不同频带的能量构成一组特征值 ,再利用这些特征值训练BP神经网络 ,并完成对心室晚电位的识别。经过对 2 8例 3导高分辨率心电图实验数据的处理 ,取得了较高的识别准确率 相似文献
66.
应用模糊极小极大神经网络研究了化合物复杂结构和性能(QSAR)之间的关系,用该法进行几组化合物致癌的识别,结果优于线性回归的方法,对此作出一些分析。 相似文献
67.
一种EEG信号盲分离和分类的神经网络方法 总被引:2,自引:1,他引:2
提出一种采用多神经网络处理脑电(EEG)信号的方法。首先,对混有噪声的脑电信号给出一种盲分离的自适应神经算法。通过寻求采样时间序列线性组合的kurtosis系数的局部极值,得出该算法的模型和步骤。在盲分离的基础上,对分离出的估计信号进一步利用Kohonen网络进行分类。将该算法用于300个EEG样本处理,并给出处理结果。 相似文献
68.
一种针对兔抗聚合人血清白蛋白抗体(anti-PHSA,Ab_1)的抗独特型抗体(anti-anti-PHSA,Ab_2),已通过免疫同种动物制成。该Ab_2具有以下特性:(1)它既可与兔anti-PHSA反应,也可与鼠的单克隆的anti-PHSA反应。(2)它与鼠的单克隆的anti-PHSA的反应,可受到PHSA和乙型肝炎病毒(HBV)上的聚合人血清白蛋白受体(PHSA-R)的抑制。(3)它可在异种动物体内诱导产生具有anti-PHSA活性的抗-抗独特型抗体(anti-anti-anti-PHSA,Ab_3),而且在收获的Ab_2血清中也查见了Ab_3。本研究不仅表明了针对PHSA的免疫应答中独特型网络调节的客观存在,而且在其抗独特型抗体(anti-Id)中,的确存在具有PHSA内映像的成分。 相似文献
69.
国人延髓动脉的观察 总被引:4,自引:0,他引:4
本文观察了110例成人脑标本的延髓外部动脉;采用动脉X线造影法和透明法,在20例人脑标本上观察了延髓内部动脉的形态和供应。将延髓表面分为四区,供应各区的外部动脉可分为相应的4群。前正中群和前外侧群动脉主要来自脊髓前动脉,前正中群动脉供应舌下神经核、内侧丘系及部分锥体束等中缝两侧结构;前外侧群动脉供应大部分锥体束;外侧群动脉来自椎动脉、小脑下后动脉、基底动脉和小脑下前动脉,主要供应网状结构、脊髓丘脑束、三叉神经脊束及核、迷走神经背核等;后群动脉来自脊髓后动脉和小脑下后动脉,主要供应薄、楔束核等。本文还讨论了延髓外侧区的血液供应及“终动脉”等问题。 相似文献
70.
本文首先给出了有关联想记忆的一系列概念,通过计算机模拟验证了网络的某些固有性质,同时指出了它的固有问题,并仿真研究了Hopfield网络中参数间的关系。 相似文献