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1.
Kindling is a process in which episodic electrical stimulation permanently increases seizure susceptibility. One mechanism to account for a change in seizure susceptibility is some alteration in signal transduction, possibly at the level of second messenger systems. In this study, male Long-Evans rats were kindled in the amygdala, and Ca2+/calmodulin (Ca2+/CaM)-dependent protein phosphorylation was assessed at the site of the primary kindled focus using one- and two-dimensional gel electrophoresis. In vitro phosphorylation of membrane and cytosol fractions in the presence of absence of Ca2+/CaM did not differentiate kindled from nonkindled amygdaloid tissue. These results suggest that changes in Ca2+/CaM-dependent phosphorylation are not related to the mechanism(s) underlying the establishment of an amygdaloid kindled focus. 相似文献
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Improved quality of care and reduction of housestaff workload using trauma nurse practitioners 总被引:2,自引:0,他引:2
J Spisso C O'Callaghan M McKennan J W Holcroft 《The Journal of trauma》1990,30(6):660-3; discussion 663-5
The University of California, Davis, Medical Center introduced the use of nurse practitioners (NPs) to the trauma service in fiscal year 1986-87 to alleviate the increasing burdens placed on the surgical housestaff in their attempt to accommodate the rising patient volume and acuity. The use of NPs was associated with a decrease in average length of stay for the seriously injured patients from 8.10 to 7.05 days while the length of stay for other patients in the hospital remained unchanged. Documentation of quality of care in the medical record increased substantially. For example, discharge summaries that were dictated by the NPs were judged complete in all aspects in at least 95% of sampled records compared with approximately 75% of records that were dictated by the residents. With introduction of the NPs, outpatient clinic waiting times decreased from 41 to 19 minutes. Patient complaints regarding the trauma team decreased from 16 to seven/year. Time saved for the housestaff averaged 352 minutes/day while the NPs were on duty. The NPs were well received by the hospital nurses, hospital quality assurance personnel, and ancillary services. They have proved to be of great value to the patients, the patients' families, the hospital, and the trauma team. 相似文献
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The role of growth factors and cytokines in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine whether changes in the amount and location of cytokines and growth factors may be associated with impaired healing in chronic leg ulcers. Biopsies from leg ulcers of 21 patients and from normal skin of nine healthy volunteers were examined immunohistochemically for selected growth factors and cytokines. Greater staining intensity was found in keratinocytes at the edges of ulcers compared to normal skin, or skin adjacent to the ulcers. Staining at the ulcer edge was more intense in nonhealing ulcers for only vascular endothelial growth factor and platelet-derived growth factor, whereas staining in the adjacent skin was more intense for all factors in the nonhealing phase. For all factors staining was cytoplasmic, suggesting production in these areas. This study shows up-regulation of the production of cytokines and growth factors in keratinocytes of chronic leg ulcers that is greater when the ulcers are nonhealing. 相似文献
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We have demonstrated a deficit in working memory and/or consolidation of information in working memory into reference memory by a single oral dose of the neurotoxin trimethyltin(TMT). Moreover, TMT causes loss of hippocampal corticosterone receptors and increases brain glial fibrillary acidic protein(GFAP), an index of the astrocytic reaction to diverse types of CNS lesions. We tried to block the TMT-induced cognitive deficit and these biochemical markers by treating rats with purified mixed gangliosides (GS) for 21 days, starting 2 days before the TMT treatment. As expected, TMT decreased the number of corticosterone receptors in hippocampi and increased the GFAP concentration in hippocampi and to a lesser extent, in frontal cortices, measured more than 8 mon after treatment. The small increase in GFAP in frontal cortices was attenuated by GS but not in hippocampi. The pronounced learning deficits caused by TMT were attenuated to a small extent by GS in the TMT-GS group, when a learning criterion was used for the last session's performance of acquired lever-directed behavior. GS also delayed the appearance of significant performance differences between Controls and TMT-treated rats, when probed with a progressive fixed ratio schedule of reinforcement. However, most measures of learning and performance indicated that GS did not block the dysfunctional consequences of TMT treatment but instead caused similar functional decrements in rats treated with water instead of TMT. Corticosterone receptors in hippocampi were reduced to about 65% of Controls in the TMT-Water, TMT-GS, and Water-GS groups. A reduction in corticosterone receptors in hippocampi after TMT treatment probably reflects the loss of one or more cell types (e.g., pyramidal cells), which is supported by the increase in GFAP in this region. However, we did not observe a reciprocal relation between steroid receptors and GFAP after GS alone, indicating that GS did not cause detectable cell loss or cell damage, measured in this manner. Thus, reactive gliosis probably was not a pre-condition for the cognitive dysfunction. The fact that the cognitive deficits are probably related to hippocampal dysfunction supports the notion of a causal relationship between corticosterone receptor reduction and/or their altered function and cognitive impairment of this special type. The possibility that our results demonstrate potential neurobehavioral toxicity of GS is discussed in light of many reports which present data that can be similarly interpreted. 相似文献
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A longitudinal study of cholinesterase changes in pregnancy 总被引:1,自引:0,他引:1
Serum cholinesterase activity was measured at intervals before, during, and after 44 pregnancies in 43 women. Three patterns of change were seen: (a) A decline in activity after conception, with no return towards pre-conception values before delivery (20 pregnancies). (b) A decline in activity accompanied by a partial or complete return to pre-conception values before delivery (19 pregnancies). (c) Either no discernible decline or increased activity during gestation (five pregnancies). We saw no association between these patterns and either the sex of the child, parity, smoking history, or alcohol intake. However, the continuous decrease in cholinesterase activity occurred in the youngest group of women, a decrease followed by an increase in the intermediate age group, and no decrease at all in the oldest group. Although not all the age-related differences quite reached statistical significance, these findings suggest that the patterns of change may be determined by some aspect of maternal physical maturity. 相似文献
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The effects of the bisbenzylisoquinoline alkaloids tetrandrine and berbamine on the action of IL-1, TNF and PAF were investigated in the rat subcutaneous air pouch model of inflammation. Both compounds were equipotent in the suppression of leukocyte infiltration into air pouches induced by IL-1 and TNF, with ED50 values in the range 20–30 mg/kg/3 days. Both were also equiptent in suppression of PMN infiltration induced by PAF with ED50 values in the same range as that for IL-1 and TNF. However, tetrandrine was more potent than berbamine as a suppressant of PAF-induced MNC infiltration, but much less potent than berbamine in carageenen-induced PMN infiltration. These results suggest that these bisbenzylisoquinolines may have value in the therapy of chronic inflammatory diseases where IL-1, TNF and PAF have a role in pathogenesis. 相似文献