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The afferent and efferent connections of the piriform cortex and the endopiriform nucleus in the rat were studied by the method of axonal transport of two fluorescent tracers: Fluoro-Gold and Fluoro-Ruby. The results indicate that both structures possess not only the connections with the olfactory system, but also the reciprocal connections with the limbic system (entorhinal cortex, amygdaloid body), thalamus (mediodorsal and midline nuclei), extrapyramidal system (ventral part of the nucleus accumbens). The topographic differences in the organisation of the association connections between the anterior and posterior parts of the piriform cortex are reported. Additionally, the reciprocal and relatively numerous connections between the endopiriformis nucleus and the piriform cortex may result in their modulatory function, which in some pathological circumstances may have a critical significance in epileptogenesis.
This article presents historical background preceding writing and publication of Jerzy Konorski book "Integrative Activity of the Brain" followed by a short description of the main topics covered in the book. Two new and original contributions of Konorski are presented in detail, his theory of the motivational processes and the organization of the sensory systems in the brain. Those two contributions are then incorporated in the revised theory of the classical and type II conditioned reflexes which constitutes the core of the book. Conclusions point out at some of the ideas which remained valuable for the present day neuroscientists. Key words: Jerzy Konorski, integrative activity of the brain, motivation theory, gnostic units, classical and instrumental conditioning, dynamic memory
Great strides have been made in the last decade regarding the importance of both genetic and environmental contributors to the risk for heavy drinking, alcohol problems, and alcohol use disorders. This lecture reviews recent research fi ndings regarding important endophenotypes contributing to these risks, (e.g. low response to alcohol, personality traits, sweet liking). Genetic fi ndings will highlight several genes that appear to contribute to the level of response to alcohol, sweet liking and some personality traits predisposing to alcohol seeking behavior. This presentation will review ongoing steps to identify additional genes in several large population studies. The lecture will also briefl y describe neurobiological background of drugs: (1) registered for alcohol treatment – disulfi ram, naltrexon, acamprosate, (2) off label drugs used in alcohol dependence: topiramat and ondasetron and (3) new medication: nelmelfene. Also, the approach of using the existing alcohol typologies (proposed by Cloninger and Lesch) in treatment proposal will be presented using our own data. Supported by MNiSW grant nr N N402 189335
Typological differentiation of coronary arteries binds to various areas of vascularisation, which could suggest essential differences between vasculatory dimensions. There are not many papers analysing the influence of heart vascularisation on epicardial vessel dimensions during postnatal human life, furthermore, there are hardly any papers dealing with the prenatal period. The subject of examination was 188 human foetuses from 4th to 7th month of prenatal life. Foetuses were fixed for minimum 3 months in 9% formalin solution. They were taken from natural abortions and did not characterise any external malformations. There was a different number of foetuses in a variety of morphological age groups. Adachi classification was used to describe all types: type I — classical, with equal coronary arteries, type II — predominance of right coronary artery, type III — predominance of left coronary artery. Speed of circumflex branch growth in different types of vascularisation is various. Analysis of the differences among dimensions of artery in various types showed there are statistically crucial ones, especially between: types III and I or types III and II.
It is known that a different ramification pattern can occur as a function of the development of the arteries of the lower limb. During a routine dissection, a variation of the deep femoral artery was found passing in front of the femoral vein in the left lower limb of a 43-year-old male cadaver. This case is reported because of its rare occurrence in the literature. The variation is discussed on the basis of the possible embryological development of the lower limb arteries.
A total of 14 patients of various ages diagnosed with schizophrenia and, as an age-matched control group, 12 healthy subjects were examined using the MRI method of neuro-imaging. The volume of the following structures was evaluated in the right and left hemispheres: the superior temporal gyrus, the basolateral temporal area (the region including the middle temporal gyrus, inferior temporal gyrus and fusiform gyrus), the parahippocampal gyrus, the hippocampal head, the amygdaloid body and the inferior horn of the lateral ventricle. In schizophrenia a significant increase in the volume of the amygdaloid body on both the left and right sides was observed. In the patients, as in the control group, we noticed significant asymmetry between the left and right sides in the volume of the structures studied. The left amygdaloid body was significantly larger than the right, whereas the left hippocampal head and the temporal horn of the lateral ventricle were smaller than the right. Our findings suggest that in the early stages of schizophrenia, despite the increased volume of the amygdaloid body, the asymmetry between the structures of the temporal lobe is still present. However, the changes observed in the temporal lobe could be related to the functional disturbances observed in this disease.
The preparations, stained according to the Nissl and Klüver-Barrera methods, were used to describe the topography and morphology of the red nucleus (RN) as well as the structure of the rubral perikarya in newborn (P0) guinea pigs. The Golgi impregnated preparations were used to distinguish types of neurons. RN is a uniform cell group and has the length from 740 to 860 µm. The Nissl stained perikarya were classified into three categories: big, medium-sized and small (A, B, C, respectively). The big perikarya, which contain a lot of tigroidal substance, were mainly observed at the caudal and ventral portions of RN. The small perikarya often have multiple nucleoli. The impregnated neurons were classified into 5 types: 1 — large, aspiny, rich-arborised multipolar cells, 2 — large and medium sized, spiny, rich-arborised fusiform or pear-shaped cells, 3 — medium-sized, spiny, rich-arborised rounded cells, 4 — medium-sized, spiny, richarborised bipolar cells, 5 — small and single medium-sized cells. The 5th type constitutes a heterogeneous population and also has neurons in different developmental stages. Intraspecies variations concerning both the length of RN and a number of the triangular perikarya of the red nucleus were observed in the examined guinea pigs.
The studies aimed at following isthmus of thyroid position changes in particular months of its intrauterine development. Survey material consisted of 124 human foetus thyroids aged 4–7 months of intrauterine development. The basic examination method was classical anatomical preparation. Three aspects were considered in thyroid isthmus position assessment: holotopy, skeletotopy and syntopy. The gland holotopy analysis was carried out with the usage of isthmus position indices elaborated especially for the studies. The results were statistically analysed. Thyroid isthmus was observed to change its position. Although statistically significant differences in thyroid isthmus position were not proved, some tendencies of the one-position changes were detected, especially of larynx and trachea skeletons. The tendencies were based on a relatively more significant lowering of isthmus in comparison with gland lateral lobes. The basic reason for thyroid isthmus position changes in the development period is a disproportion between foetus gland and cervix growth rates.
Cardiac arrhythmias have troubled patients and fascinated physicians for centuries. The twentieth century was an era of progress, when the mechanism of cardiac disorders became more commonly recognised. Arrhythmias may be due to abnormalities of automaticity, to abnormalities of conduction, or to a combination of both. In order for re-entry to occur, an area of slowing conduction combined with unidirectional block must be present. Much investigation has centred on the underlying re-entry mechanisms of atrial flutter. In the light of these facts, it would seem that a close acquaintance with the detailed topography of the vena cava orifice (cavo), coronary sinus orifice (sinus) and the attachment of the septal leaflet of the tricuspid valve (tricupid) area could be of great interest, especially for invasive cardiologists. The research was conducted on material consisting of 41 hearts of humans of both sexes from the age of 12 to 80 (6 female, 35 male). Classical macroscopic methods of anatomical evaluation were used. The following measurements were made: the shortest distance between the Eustachian valve and the attachment of the tricuspid valve on the left margin of the coronary sinus orifice (diameter 1), the distance between the attachment of the tricuspid valve and the inferior margin of the sinus orifice (diameter 2), the distance between the Eustachian valve and the attachment of the tricuspid valve on the right margin of the coronary sinus orifice (diameter 3), the distance between the inferior margin of the vena cava inferior and the attachment of the tricuspid valve (diameter 4) and, finally, the diameter between the attachment of the septal cups of the tricuspid valve and the external border of the vena cava inferior (diameter 5). No correlation was found between the age and sex of the three groups of the material. The dimensions of the structure examined were similar in the three groups of hearts. In young adult hearts all the diameters measured ranged from 4 to 47 mm The average diameters were, respectively: 15.02 mm (diameter 1), 8.97 mm (diameter 2), 17.27 mm (diameter 3), 26.87 mm (diameter 4), 36.42 mm (diameter 5). In the mature adult hearts all the diameters measured ranged from 8 to 45 mm: 18.19 mm (diameter 1), 10.54 mm (diameter 2), 19.95 mm (diameter 3), 28.90 mm (diameter 4), 39.63 mm (diameter 5). In the older adults hearts all the diameters measured ranged from 4 to 47 mm. The average diameters were, respectively: 15.65 mm (diameter 1), 8.70 mm (diameter 2), 7.25 mm (diameter 3), 26.80 mm (diameter 4), 35.85 mm (diameter 5).
The morphological features of nitric oxide synthase (NOS)-containing neurons in the rat claustrum (Cl) were studied during the period of four months after birth. Forty-five animals divided into nine groups, according to survival period (P0, P4, P7, P10, P14, P21, P28, P60, P120) were used in the study. The immunocytochemical staining to neuronal NOS was performed and the material was studied both qualitatively and quantitatively using unbiased stereological methods. Our observations indicate that the process of maturation of NOS-immunoreactive (ir) neurons in Cl takes place during the early postnatal period. We report the increase of numerical density of immunoreactive neurons, changes in neuronal size, expressed by the decrease of the percentage of small neurons with simultaneous increase of the participation of medium-sized neurons and large neurons. In the whole studied period the prevalence of oval and fusiform neurons is observed. However, the increase of the proportion of multipolar neurons takes place. Round neurons are most characteristic in the youngest groups of animals and later become dominated by the developing subpopulations of irneurons of other shapes. In the anterior, central and posterior parts of Cl, a similar pattern of maturation of NOS-ir neurons is observed. No prevalence of characteristically shaped neurons is observed in any part of Cl. The adult-like pattern of morphological features in the NOS-ir neuronal population in Cl is reached in the third postnatal week. The maturation of NOS-ir neurons in the claustrum is a dynamic process which is not stabilised at the moment of birth. It may be assumed that characteristic changes of the NOS-ir population of neurons may be influential on the physiological processes observed in Cl. These may in particular have some importance for the processes of synaptogenesis and establishing as well as refining of numerous claustral connections with the other structures of the central nervous system.
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