F J Martínez Alonso

Learn More
We have studied the fusion process of myoblasts in the mytome corresponding to H.H. stages 22, 23 and 24 from calcitonin-treated chick embryos and their untreated controls. The micrograph images of this process were studied to detect the ultrastructural changes in myoblast morphology that could be associated with the known hormonal and biochemical changes(More)
The effects of different fixatives, dehydration procedures, and embedding media on the structural and ultrastructural preservation of young chick embryos (Hamburger and Hamilton stages 18-24) have been studied by means of light and electron microscopy techniques. Under the light microscope, the results obtained with the use of Bouin, glutaraldehyde, or(More)
We have studied the formation of collagen fibrils in 'activated fibroblasts' of tendo Achillis of rabbits. The tendon was in the process of regeneration after experimental partial tenotomy. Samples were taken from the peri-incisional region and analysed by transmission electron microscopy. Ultrastructural examination showed the presence of a 'fine dense(More)
The ultrastructure of the dorsal periaqueductal nucleus capillaries of the mesencephalon in the cat was studied under the electron microscope in relation to the hematoencephalic barrier, and its four structural levels: 1. Endothelium; 2. Basal membrane; 3, Pericytes; and 4. Glial prolongations. An analysis was performed of what occurs in these four(More)
In this study, the hypothesis of a possible biogenesis of the ciliary roots is suggested, after observing the cilia neurons under the electron microscope, which were found as an exception in the periaqueductal nucleus of the mesencephalon in the domestic cat, conserving the potential to differentiate the cilia, basal bodies and ciliary roots. The(More)
The neurons of the dorsal periaqueductal nucleus of the mesencephalon and their synaptic contacts were observed under a transmission electron microscope. We found various types of synapses which constituted an exception to Cajal's neuron theory (law of neuron independence). Some of these synapses had an open communicating or continuity 'passage' between the(More)
In this study, an ultrastructural and immunohistochemical examination was carried out on the presence of an 'atrial-natriuretic-peptide (ANP)-like factor' in the myoblasts of the brachial myotome of chicken embryos at Hamburger and Hamilton stages 17 +/- to 19. The results of the immunohistochemical study indicate that, at these stages of their development,(More)
  • 1