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Using computerized tomography 7 human fetuses were examined, aging 24 to 39 weeks. Frontal sinus developes in the region of frontal recess of the frontal nasal meatus in a fetus aging 27 weeks. In the latter weeks of the fetal life the frontal recess of the middle nasal meatus transforms upwards into an oval thin-walled space corresponding to the developing frontal sinus. It adheres to the ethmoidal slabyrinth, integrating with it.
A CT study was performed on 8 foetuses aged between 20 and 38 weeks. In foetuses at the 20th week the semicircular canals, the spiral canal of the cochlea and the initial (labyrinthine) part of the facial canal are visible. At week 24 the tympanic part of the facial canal is observed. In the 31st week the cochlea is divided into 2 compartments, and in the 38th week the vestibular aqueduct and osseous labyrinth are seen.
There is no agreement in the literature as to the time of the onset and progress of the vertebral column ossification. The aim of the present study was to determine the precise sequence of ossification of the neural arches and vertebral centra. Histological and radiographic studies were performed on 27 human foetuses aged from 9 to 21 weeks. It was found that the ossification of vertebrae commences in foetuses aged 10 and 11 weeks. Ossification centres appear first for neural arches in the cervical and upper thoracic vertebrae and by the end of 11th week they are present in all thoracic and lumbar neural arches. In the vertebral centra in foetus of 10 weeks ossification was found in the lower 7 thoracic and first lumbar vertebrae. By the end of 11th week ossification is present in the lower 4 cervical, all thoracic, all lumbar and 4 sacral vertebral centra. The study indicates that ossification of the neural arches proceeds in the craniocaudal direction, whereas in the vertebral centra it progresses from the lower thoracic vertebrae into both directions. Different shapes of ossification centres were also described. (Folia Morphol 2013; 72, 3: 230–238)
Seven skulls of newborns and of infants aged 3 weeks to 12 months were studied using computed tomography. Size of the maxillary sinuses was measured. Between 3rd and l2nd week of life the ethmoidal sinus formed small spaces in ethmoidal labyrinth. Maxillary sinus could be noted at the level of lower orbital margin. In newborns, it formed a shallow indentation in the lateral wall of the nasal cavity. The anteroposterior dimension of the sinus was greater- than the two remaining dimensions. Beginning from the 3rd month of life, number of ethmoidal cells increased, maxillary sinuses enlarged and entered the body of the maxilla. Between 6th and l2th month, the mediolateral and the superoinferior dimensions of the sinuses increased. Small air spaces were also seen in the part of sphenoid bone, corresponding to sphenoidal sinueses.
The aim of the study was to examine the neurochemical background of differences in the individual responses to conditioned aversive stimuli, using the strength of a rat conditioned freezing response (the contextual fear test), as a discriminating variable. It was shown that high responder (HR), i.e. rats with duration of a freezing response one standard error, or more, above the mean value, had a higher c-Fos activity in the FrA and PrL prefrontal cortical areas, and stronger 5HT immunostaining in the FrA. However, these animals had lower CRF immunostaining in the same cortical areas in comparison with low responder (LR), i.e. rats with the duration of a freezing response one standard error, or more, below the mean value. The LR group vocalized more during test session in the aversive band, and had higher serum levels of corticosterone, examined 10 min after test session. It was shown that different natural patterns of responding to conditioned aversive stimuli are associated with different expression of CRF and serotonergic- innervation of prefrontal cortical areas.
Three rare anatomical variations were found during study on hepatic arterial vascularisation in multidetector computed tomography angiography. In the first described variation the common hepatic artery (CHA) arises from the celiac trunk (CTr) and supplies right hepatic lobe. The left lobe of the liver is supplied by aberrant left hepatic artery originating as a common trunk with the left gastric artery and the splenic artery. This variation may correspond to the type 2 in Michels’ classification coexisting with one of three possible patterns of the CTr division (when the CHA is the first branch of the CTr and the gastrosplenic trunk is the second one). The second variation corresponds to the very early bifurcation of the CHA arising from the CTr. Both, the right and left hepatic arteries originate separately from the CTr. The gastroduodenal artery (GDA) originates from the left hepatic artery. It may be regarded as the variation of most common type 1 according to Michels. In the third case the CHA gives raise to the GDA and terminates as the right hepatic artery supplying the right lobe of the liver only. The proper hepatic artery is missing and the left hepatic artery arises from the GDA. This variation does not correspond to any types of Michels’ classification. (Folia Morphol 2014; 73, 4: 531–535)
We examined the effects of midazolam and D-cycloserine on the release of GABA in the basolateral amygdala (BLA) of high (HR) and low (LR) anxiety rats during extinction session of a conditioned fear test. HR and LR anxiety rats were selected according to their behaviour in the contextual fear test (i.e., the duration of a freezing response was used as a discriminating variable). Administration of D-cycloserine (15 mg/kg, i.p.), significantly enhanced the inhibition of an aversive context-induced freezing response observed during the extinction session in HR and LR rats 7 days after contextual fear test. It was also found that midazolam and D-cycloserine facilitated the GABA release in HR rats under the influence of conditioned fear. HR rats pretreated with saline had higher expression of alpha-2 subunits of GABA-A receptor in BLA compared to LR rats. Administration of D-cycloserine and midazolam increased the expression of alpha-2 subunits in the BLA of HR rats compared to HR rats pretreated with saline, and to drug administered LR rats. Moreover, D-cycloserine enhanced the expression of alpha-2 subunits and gephyrin in the prefrontal cortex of HR rats. Together, these findings suggest that animals that are more vulnerable to stress differ in the expression of alpha-2 subunits of GABA-A receptor in amygdala and prefrontal cortex which is involved in the control of emotional behaviour. These animals might have innate deficits in forebrain systems that control the activity of the limbic structures including GABAergic innervation of the BLA. These data indicate also possible neurochemical mechanisms for individual differences observed in response to anxiolytic drugs among patients with anxiety disorders. The current results also suggest that activation of glutamatergic function can initiate neural changes which improve fear extinction and provide preclinical evidence in support of the clinical use of NMDA(R) modulators for the treatment of anxiety-related disorders.
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