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991.
Paulson C 《Nursing education perspectives》2011,32(6):395-399
A lack of research exists regarding the impact of substantive curriculum reform on faculty teaching and attitudes. This report of an interpretive phenomenological study of one group of baccalaureate nursing faculty undergoing implementation of an innovative curriculum revealed that the curricular structure and program philosophy offered multiple new challenges. These included the integration of multiple concurrent learning activities, expansion of simulation, and a renewed focus on student assessment. The study design used Heideggerian hermeneutics, a reflexive approach to text analysis of interviews of seven full-time faculty who had worked in the school's traditional curriculum prior to the implementation of the clinical immersion model. The research offers insights into faculty adaptation to curriculum change and its effect on teaching and instruction. The results of this study may assist other schools contemplating or in the process of similar overarching program reforms. 相似文献
992.
Kathrine Skak Madsen William F.C. Baaré Martin Vestergaard Lisser Rye Ejersbo Christian Gerlach Olaf B. Paulson Terry L. Jernigan 《Neuropsychologia》2010,48(4):854-1959
Cognitive control of thoughts, actions and emotions is important for normal behaviour and the development of such control continues throughout childhood and adolescence. Several lines of evidence suggest that response inhibition is primarily mediated by a right-lateralized network involving inferior frontal gyrus (IFG), presupplementary motor cortex (preSMA), and subthalamic nucleus. Though the brain's fibre tracts are known to develop during childhood, little is known about how fibre tract development within this network relates to developing behavioural control. Here we examined the relationship between response inhibition, as measured with the stop-signal task, and indices of regional white matter microstructure in typically-developing children. We hypothesized that better response inhibition performance would be associated with higher fractional anisotropy (FA) in fibre tracts within right IFG and preSMA after controlling for age. Mean FA and diffusivity values were extracted from right and left IFG and preSMA. As hypothesized, faster response inhibition was significantly associated with higher FA and lower perpendicular diffusivity in both the right IFG and the right preSMA, possibly reflecting faster speed of neural conduction within more densely packed or better myelinated fibre tracts. Moreover, both of these effects remained significant after controlling for age and whole brain estimates of these DTI parameters. Interestingly, right IFG and preSMA FA contributed additively to the prediction of performance variability. Observed associations may be related to variation in phase of maturation, to activity-dependent alterations in the network subserving response inhibition, or to stable individual differences in underlying neural system connectivity. 相似文献
993.
994.
We combined behavioral testing with brain imaging using (99m)Tc-HMPAO (Amersham Health) to identify CNS structures reflecting alterations in pain perception in the streptozotocin (STZ) model of type I diabetes. We induced diabetic hyperglycemia (blood glucose >300 mg/dl) by injecting male Sprague-Dawley rats with STZ (45 mg/kg i.p.). Four weeks after STZ-diabetic rats exhibited behaviors indicative of neuropathic pain (hypersensitivity thermal stimuli) and this hypersensitivity persisted for up to 6 weeks. Imaging data in STZ-diabetic rats revealed significant increases in the activation of brain regions involved in pain processing after 6 weeks duration of diabetes. These regions included secondary somatosensory cortex, ventrobasal thalamic nuclei and the basolateral amygdala. In contrast, the activation in habenular nuclei and the midbrain periaqueductal gray were markedly decreased in STZ rats. These data suggest that pain in diabetic neuropathy may be due in part to hyperactivity in somatosensory structures coupled with a concurrent deactivation of structures mediating antinociception. 相似文献
995.
Paulson L Martin P Ljung E Blennow K Davidsson P 《Journal of neural transmission (Vienna, Austria : 1996)》2007,114(7):885-891
Summary MK-801, a glutamergic, N-methyl-D-aspartate (NMDA)-receptor antagonist that mediates neurotransmission and has psychotomimetic
properties, giving schizophrenia-like symptom. The objective of this study was to investigate the effects on the thalamic
and cortical proteome of one typical (haloperidol) and one atypical (clozapine) antipsychotic drug in interaction with MK-801
in rats. Rats received subcutaneous injections of MK-801 or vehicle (controls) or MK-801 together with concurrent administration
of haloperdol or clozapine for eight days. Protein samples from thalamus and cortex were analyzed with two-dimensional gel
electrophoresis in combination with mass spectrometry. MK-801 induced alterations in the levels of three proteins in both
cortex and thalamus. Clozapine reversed all the protein changes. Haloperidol reversed two. Both antipsychotics induced new
protein changes in both cortex and thalamus not seen after MK-801-treatment by alone. In conclusion, the MK-801 animal model
shows potential for investigation of different antipsychotic drugs and biochemical treatment effects in schizophrenia. 相似文献
996.
Nopoulos P Magnotta VA Mikos A Paulson H Andreasen NC Paulsen JS 《The American journal of psychiatry》2007,164(9):1428-1434
OBJECTIVE: Cortical morphology was evaluated in subjects with known gene expansion for Huntington's disease and no manifest disease. METHOD: Magnetic resonance imaging scans were obtained for 24 subjects with preclinical Huntington's disease and were compared to those for 24 matched healthy subjects by means of novel imaging methods to quantify aspects of cortical structure. RESULTS: In relation to the comparison subjects, those with preclinical Huntington's disease showed altered cortex morphology with enlargement of gyral crowns and abnormally thin sulci. These changes were manifested in global alterations of gyral and sulcal shape. CONCLUSION: These findings lend support to the notion that, in addition to the degenerative process, abnormal neural development may also be an important process in the pathoetiology of Huntington's disease. 相似文献
997.
W D Paulson 《The American journal of medicine》1986,81(6):995-1000
The relation between the serum anion gap and the serum total carbon dioxide concentration was studied in 100 admissions of patients with diabetic ketoacidosis and 43 normal control subjects. In 20 admissions of patients with diabetic ketoacidosis (Group 1), the patients had no other conditions or medications known to alter acid-base or electrolyte homeostasis, whereas in 80 admissions of patients with diabetic ketoacidosis (Group 2), the patients had at least one of these factors. Analysis of the change in total carbon dioxide compared with the change in anion gap in Group 1 and control subjects revealed the following relation: change in total carbon dioxide = 0.74 + 1.00 X change in anion gap, in meq/liter (r = 0.886, p less than 10(-7]. The 95 percent prediction interval for detecting mixed acid-base disorders with this equation was +/- 8 meq/liter. Analysis of all admissions of patients with diabetic ketoacidosis and control subjects combined showed that the anion gap increased 0.24 meq/liter per mg/dl increase in blood urea nitrogen (with total carbon dioxide constant). Because the highest blood urea nitrogen level in Group 1 and control subjects was 22 mg/dl, the change in total carbon dioxide-change in anion gap regression is generally not valid for blood urea nitrogen levels higher than 22 mg/dl. Thus, both the wide prediction interval and volume depletion (as reflected by blood urea nitrogen level) impair the usefulness of the anion gap as a screen for mixed acid-base disorders in patients with diabetic ketoacidosis. 相似文献
998.
The mineralized parts of the teeth of 17 human fetal dentitions, aged 15-38 weeks, were measured mesio-distally and occluso-cervically. The growth pattern of the incisors, with particular emphasis on the changes at the developing incisal edge was studied. Contralateral teeth in the same arch developed at approximately the same rate and with mirror-image morphology. Mineralization started in the upper and lower central incisors, followed by the corresponding lateral incisors. It then progressed at approximately the same rate for both incisors. At first, mesio-distal enamel growth was more significant, but was surpassed by occluso-cervical development later. Five development stages were identified as the incisors developed from a central lobe to the mature form. The main component of growth for the mesial lobe was in the incisal direction, and for the distal lobe in a distal direction, resulting in the characteristic approximal asymmetry of these teeth. 相似文献
999.