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排序方式: 共有778条查询结果,搜索用时 15 毫秒
151.
152.
Camacho-Carrasco Pilar Renau-Cerrillo Marina Campuzano-Bitterling Borja Martinez-de-la-Mata Jessica Vives-Barquiel Marian 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2022,32(7):1407-1413
Femur fractures reduction can be technically challenging due to the deforming forces exerted by the muscles causing displacement of the fracture fragments. Cerclage wiring is one of the reduction techniques frequently performed, allowing anatomical reduction of the fragments and a more stable fixation when an accurate closed reduction is not possible. We describe a modified cerclage wiring through a minimally invasive technique, using a conventional cannulated C-shaped passer.
相似文献153.
Rodríguez-Herreros B López-Moliner J 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2008,191(3):321-329
It has been shown that motion after-effects (MAE) may affect the perceived position of moving objects and, more recently,
that MAE signals can also affect pursuit eye movements: smooth pursuit eye movements are favoured by the illusory motion percept
that is caused by motion adaptation. Here we investigated the relationship between MAE and arm movements. The objective of
our research was: (1) to analyze possible effects of MAE when the arm tracks the changing position of a moving object, and
(2) to investigate the influence of MAE on pointing movements to both static and moving targets. Our results show that the
(unseen) hand position was trailing the target much less when target and MAE direction was the same. At the end of manual
pursuit, subjects caught up with the moving target. However, when target direction was opposite the MAE, subjects’ hands moved
more slowly, causing larger lags between the target and the hand position (Experiment 1). In Experiment 2, we found a similar
effect of motion signals when subjects pointed to a moving target but found no effect of MAE when pointing to a static object
(Experiment 3). We conclude that the effect of motion signals is only revealed when we need to update the changing position
of a target. 相似文献
154.
Muñoz LM Holgado BL Martínez-A C Rodríguez-Frade JM Mellado M 《Immunology letters》2012,145(1-2):23-29
A broad array of biological responses including cell polarization, movement, immune and inflammatory responses, as well as prevention of HIV-1 infection, are triggered by the chemokines, a family of secreted and structurally related chemoattractant proteins that bind to class A-specific seven-transmembrane receptors linked to G proteins. Chemokines and their receptors should not be considered isolated entities, as they act in complex networks. Chemokines bind as oligomers, or oligomerize after binding to glycosaminoglycans on endothelial cells, and are then presented to their receptors on target cells, facilitating the generation of chemoattractant gradients. The chemokine receptors form homo- and heterodimers, as well as higher order structures at the cell surface. These structures are dynamic and are regulated by receptor expression and ligand levels. Complexity is even greater, as in addition to regulation by cytokines and decoy receptors, chemokine and receptor levels are affected by proteolytic cleavage and other protein modifications. This complex scenario should be considered when analyzing chemokine biology and the ability of their antagonists to act in vivo. Strategies based on blocking or stabilizing ligand and receptor dimers could be alternative approaches that might have broad therapeutic potential. 相似文献
155.
Durán AC Fernández B Grimes AC Rodríguez C Arqué JM Sans-Coma V 《Journal of anatomy》2008,213(5):597-606
It has been generally assumed that the outflow tract of the chondrichthyan heart consists of the conus arteriosus, characterized by cardiac muscle in its walls. However, classical observations, neglected for many years, indicated that the distal component of the cardiac outflow tract of several elasmobranch species was composed of tissue resembling that of the ventral aorta. The present study was outlined to test the hypothesis that this intrapericardial, non-myocardial component might be homologous to the actinopterygian bulbus arteriosus. The material consisted of Atlantic catshark adults and embryos, which were examined by means of histochemical and immunohistochemical techniques for light and fluorescence microscopy. In this species, the distal component of the outflow tract differs histomorphologically from both the ventral aorta and the conus arteriosus; it is devoid of myocardium, is covered by epicardium and is crossed by the coronary arterial trunks. In the embryonic hearts examined, this distal component showed positive reactivity for 4,5-diaminofluorescein 2-diacetate (DAF-2DA), a fluorescent nitric oxide indicator. These findings, together with other observations in holocephals and several elasmobranch species, confirm that chondrichthyans possess a bulbus arteriosus interposed between the conus arteriosus and the ventral aorta. Therefore, the primitive heart of gnathostomates consists of five intrapericardial components, sinus venosus, atrium, ventricle, conus arteriosus and bulbus arteriosus, indicating that the bulbus arteriosus can no longer be regarded as an actinopterygian apomorphy. The DAF-2DA-positive reactivity of the chondrichthyan embryonic bulbus suggests that this structure is homologous to the base of the great arterial trunks of birds and mammals, which derives from the embryonic secondary heart field. 相似文献
156.
157.
158.
159.
Paloma Vilchis-Len Josu Hrnandez-Varela Jos Jorge Chanona-Prez Raul Borja Urby Rodolfo Estrada Guerrero 《Materials》2021,14(21)
This study presents a nanocomposite developed with PVA, multiwall carbon nanotubes (CNTs) doped with nitrogen, and NaDDBS, which change the electrical properties of the polymer and its viscosity to be used in electrospinning process for obtaining mats of nano/macro fibers. The proposed nanocomposite was characterized using Fourier transform-infrared and Raman spectroscopy techniques, confirming the presence of the CNxs immersed in the polymer. High-resolution transmission electron microscopy was used to obtain the micrographs that showed the characteristic interplanar distances of the multiwall CNT in the polymeric matrix, with values of 3.63 Å. Finally, the CNx mats were exposed to various aqueous solutions in a potentiostat to demonstrate the effectiveness of the nanofibers for electrochemical analysis. The CNx-induced changes in the electrical properties of the polymer were identified using cyclic voltammograms, while the electrochemical analysis revealed supercapacitor behavior. 相似文献
160.
Lourdes Ortiz-Alvarez Huiwen Xu Xinyu Di Isabelle Kohler Francisco J. Osuna-Prieto Francisco M. Acosta Ramiro Vilchez-Vargas Alexander Link Julio Plaza-Díaz Mario van der Stelt Thomas Hankemeier Mercedes Clemente-Postigo Francisco J. Tinahones Angel Gil Patrick C. N. Rensen Jonatan R. Ruiz Borja Martinez-Tellez 《Nutrients》2022,14(10)
Objective: To investigate the association of plasma levels of endocannabinoids with fecal microbiota. Methods: Plasma levels of endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), as well as their eleven analogues, and arachidonic acid (AA), were measured using liquid chromatography-tandem mass spectrometry in 92 young adults. DNA extracted from stool samples was analyzed using 16S rRNA gene sequencing. Lipopolysaccharide levels were measured in plasma samples. Results: Plasma levels of endocannabinoids and their analogues were not related to beta or alpha diversity indexes. Plasma levels of AEA and related N-acylethanolamines correlated positively with the relative abundance of Faecalibacterium genus (all rho ≥ 0.26, p ≤ 0.012) and Akkermansia genus (all rho ≥ 0.22, p ≤ 0.036), and negatively with the relative abundance of Bilophila genus (all rho ≤ −0.23, p ≤ 0.031). Moreover, plasma levels of 2-AG and other acylglycerols correlated positively with the relative abundance of Parasutterella (all rho ≥ 0.24, p ≤ 0.020) and Odoribacter genera (all rho ≥ 0.27, p ≤ 0.011), and negatively with the relative abundance of Prevotella genus (all rho ≤ −0.24, p ≤ 0.023). In participants with high lipopolysaccharide values, the plasma levels of AEA and related N-acylethanolamines, as well as AA and 2-AG, were negatively correlated with plasma levels of lipopolysaccharide (all rho ≤ −0.24, p ≤ 0.020). Conclusion: Plasma levels of endocannabinoids and their analogues are correlated to specific fecal bacterial genera involved in maintaining gut barrier integrity in young adults. This suggests that plasma levels of endocannabinoids and their analogues may play a role in the gut barrier integrity in young adults. 相似文献