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71.
Oxygen mass transfer calculations in large arteries 总被引:1,自引:0,他引:1
Parkinsonism is characterised by overactive glutamatergic transmission in the cortico-striatal and subthalamo-medial pallidal pathways. Local blockade of glutamatergic transmission in these pathways can alleviate parkinsonian symptoms. The effectiveness of the treatment, however, is often limited by the simultaneous appearance of unwanted side-effects. These side-effects, including ataxia and dissociative anaesthesia, are particularly problematic when N-methyl-D-aspartate (NMDA) antagonists are used. In an attempt to overcome these problems we have attempted to manipulate excitatory amino acid (EAA)-mediated neurotransmission indirectly by targeting the NMDA receptor associated modulatory sites. We review evidence which demonstrates that antagonists for both the NMDA associated glycine and polyamine sites can reverse parkinsonian symptoms when injected intra-cerebrally in both MPTP-treated and bilateral 6-OHDA lesioned marmosets without eliciting unwanted side-effects. We further review preliminary data which suggest that ifenprodil, a polyamine site antagonist, has striking anti-parkinsonian actions in the marmoset. Potential mechanisms of action underlying these effects are discussed in terms of NMDA receptor subtypes and the neuroanatomical locus of action. The anti-parkinsonian efficacy of intra-striatally administered EAA antagonists leads us to question the view of dopamine acting in the striatum as a simple neuromodulator. 相似文献
72.
Brent M. Phares Glenn A. Washer Dennis D. Rolander Benjamin A. Graybeal Mark Moore 《Canadian Metallurgical Quarterly》2004,9(4):403-413
Routine inspection is the most common form of highway bridge inspection to satisfy the requirements of the National Bridge Inspection Standards. The accuracy and reliability of documentation generated during these inspections are critical to the allocation of Department of Transportation construction, maintenance, and rehabilitation resources. Routine inspections are typically completed using only the visual inspection technique and rely heavily on subjective assessments made by bridge inspectors. In light of this, and given the fact that visual inspection may have other limitations that influence its reliability, the Federal Highway Administration initiated an investigation to examine the reliability of visual inspection as it is currently applied to bridges in the United States. This paper will summarize results from this study related to the accuracy and reliability of routine inspection documentation. A number of important conclusions were developed from the experimental study. Generally, it was found that all structural condition documentation is collected with significant variability. Specifically, 95% of primary element condition ratings for individual bridge components will vary within two rating points of the average and only 68% will vary within one point. Documentation generally collected to support condition ratings also has significant variability as exemplified by the number and types of field notes and photographs taken by inspectors. With respect to the use of element-level inspections, it was found that element usage was generally consistent with the Commonly Recognized Element Guide. However, there is significant variability in the condition state assignments of those elements and in some cases the condition states are not applied correctly to particular elements. 相似文献
73.
Conditioned eyeblink responses are presumably learned in the cerebellum and relayed to motoneurons by way of the red nucleus. Projections from the red nucleus to cerebellar cortex (Larsell's lobule HVI) could be important for shaping temporally adaptive features of the conditioned response. Rabbits that had pipettes containing wheat germ agglutinated horseradish peroxidase (WGA-HRP) implanted unilaterally into HVI showed retrograde labeling of neurons within subregions of the contralateral red nucleus implicated in eyeblink conditioning by lesioning and recording studies. Retrogradely labeled neurons were also observed in the pontine nuclei, inferior olive, and spinal trigeminal nucleus pars oralis. Projections to HVI provide a possible neural substrate for implementing time-derivative computational models of learning in the cerebellum. Time-derivative models are capable of describing the timing and topography of conditioned responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Cohen Lawrence H.; Burt Charles E.; Bjorck Jeffrey P. 《Canadian Metallurgical Quarterly》1987,23(4):583
A longitudinal design was used to test the effects of life events experienced by young adolescents and their parents. The criteria were the adolescents' depression, anxiety, and self-esteem. The longitudinal analysis revealed a significant effect for the adolescents' controllable, but not uncontrollable, negative events. However, causal analyses revealed that this effect was the result of the significant relation between initial adjustment and the subsequent occurrence of controllable life stress (e.g., school suspension). The longitudinal analysis also revealed the stress-protective role of positive events, but only with respect to girls' self-esteem. There was no longitudinal support for the role of the parents' negative life events. These findings do not support the etiological importance of an accumulation of relatively discrete negative events experienced by early adolescents and their parents, but they do suggest the need (a) to conceptualize (controllable) life stress as a dependent variable in future research on developmental psychopathology; (b) to examine gender differences in early adolescent life stress; and (c) to develop more sophisticated measures of family life stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Evaluated the efficacy of outpatient group treatment of chronic pain and the effect of spouse involvement in treatment in chronic pain patients ranging in age from 23 to 69 yrs who were randomly assigned to couples group treatment (n?=?17), patient-only group treatment (n?=?14), or waiting-list controls (n?=?12). 29 Ss had low back pain; the remaining Ss reported pain in the knee, arm, leg, hip, head, and phantom limb. The Ss completed the MMPI—168 and measures of health-related psychosocial and physical dysfunction and marital satisfaction. Results indicate that the 16-hr cognitive-behavioral program produced reductions in pain, somatization, spouse-observed pain behavior, physical and psychosocial dysfunction, spouse-rated dysfunction, and utilization of health care resources. Depression was not affected by treatment. Spouse involvement did not facilitate response to treatment on any variables. Also, Ss in the individual condition only showed improved marital satisfaction. All treatment gains were maintained at 3-mo to 7-mo follow-ups. Results indicate that brief outpatient treatment can significantly ameliorate chronic pain problems, and spouse involvement is not essential for a positive response to treatment. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
77.
Suggests that "manualized training" is most effective at increasing adherence to the technical procedures characterizing the treatment under scrutiny. There is minimal evidence that other skills associated with therapeutic competence are acquired or enhanced to the extent found with technical adherence. Drawing on findings from a study of manual-guided training of therapists in the techniques of brief therapy (H. H. Strupp and J. L. Binder, 1984), the author offers recommendations for improving therapy training. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
When Bonner & Moore was formed in 1956, few-if any-other firms were offering computer consulting services to private industry. Over the years, Bonner & Moore's software development and computer modeling projects took the company far and wide, from Texas oil refineries to the other side of the globe. Its computer services created a solid financial success. 相似文献
79.
Liew Jeffrey; Eisenberg Nancy; Losoya Sandra H.; Fabes Richard A.; Guthrie Ivanna K.; Murphy Bridget C. 《Canadian Metallurgical Quarterly》2003,17(4):584
Relations of heart rate and skin conductance reactions to mildly evocative empathy-inducing slides with socioemotional functioning were examined for 154 children (mean age = 9 years, 5 months). In addition, maternal expressivity was tested as a moderator of these relations. Parents and teachers rated children's socioemotional functioning, and a behavioral measure of children's regulation was obtained. Boys who exhibited higher skin conductance and higher heart rate to slides depicting negative emotions were better regulated, less emotionally intense, and better adjusted than their peers. Furthermore, boys' regulation and adjustment were positively related to such physiological responding to negative slides if maternal negative expressivity was relatively low or moderate, but not high. Fewer findings were obtained for girls or for positive slides. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
As cropland and pasture have replaced forest and cerrado in Brazilian Amazônia, concern has mounted over the effects of changing the biogeochemical and hydrological properties of one of the world's great storehouses of biomass and biodiversity. Although much recent effort has focused on the location, effects, and causes of deforestation and cerrado conversion, much less is known about the basin-wide spatial distribution and density of the land use following conversion for crops or pasture.In this paper, we use census and satellite records to develop maps of the distribution and abundance of major agricultural land uses across 4.5×108 ha of Brazilian Amazônia in 1980 and 1995. Results indicate an overall expansion of 7.0×106 ha in total agricultural area in Brazilian Amazônia between 1980 and 1995. The net change during this period is estimated for three different land-use types: croplands (an increase of 0.8×106 ha), natural pastures (a decrease of 8.4×106 ha), and planted pastures (an increase of 14.7×106 ha). These estimates, the first spatially explicit quantifications of agricultural land-use activities in 1980 and 1995 across Brazilian Amazônia, are shown to be consistent with the results of applying a land use change and secondary regrowth model to published deforestation rates for the period.The resulting time slices, presented for each land-use category at 5-min (∼9 km) spatial resolution, allow for the quantification of land-use changes in this region for biogeochemical, demographic and economic models. Several foci of agricultural change existed within Brazilian Amazônia during this period: in the state of Pará, cropland was lost and planted pasture increased markedly; in Mato Grosso, both cropland and planted pasture increased; in Rondônia, planted pasture replacing forest was the primary route to agricultural expansion. 相似文献