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81.
Internal stability and discriminant validity of the Neuropsychology Behavior and Affect Profile (L. Nelson et al, 1989) were examined in samples of 70 stroke patients and 88 elderly controls. The test is designed to yield indices of premorbid (before-item subset) and present (now-item subset) levels of emotional functioning in each of 5 scales. With coefficient alphas ranging from .76 to .87, results indicated moderate to high internal stability. The test was also able to reliably distinguish between the criterion stroke sample (n?=?42) and a matched group of elderly controls in terms of present levels of emotional functioning (2 wks poststroke). When discriminant validity was examined in terms of premorbid emotional status (before-item subset), group differences were unexpectedly obtained. Clinical and research implications of these results are discussed, noting the possibility of early, noncognitive correlates preceding stroke. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
Presynaptic paired-pulse facilitation (PPF) rate decreased in most CA1 pyramidal neurones following the long-term potantiation (LTP) induction. The decrease correlated with the LTP magnitude as well as with the initial (pretetanic) PPF rate. The data obtained suggests an involvement of presynaptic mechanisms in maintaining the early and the delayed LTPs.  相似文献   
83.
Cerebellar granule cells isolated from postnatal day 7 mice, and cultured in minimal medium containing only insulin-like growth factor-I (IGF-I), both survive and differentiate. This differentiation is marked by neurite growth and expression of genes associated with terminal differentiation, the myocyte-specific enhancer factor 2A (MEF2A) and the alpha 6 subunit of the gamma-aminobutyric acidA receptor (GABAA alpha 6). Percoll gradient purified granule cells maintained without IGF-I, in minimal medium alone or in medium containing the antioxidant N-acetylcysteine (NAC), also express MEF2A and GABAA alpha 6. Thus, cultured granule neurons can differentiate to some extent cell-autonomously and IGF-I may not be a critical factor for this process.  相似文献   
84.
H. Cohen  Q. Jiang 《Acta Mechanica》1995,109(1-4):1-10
Summary Motions of hyperelastic materials involving surfaces of strain or stress discontinuities are generally dissipative in the sense that, in any portion of the body that is traversed by a moving singular surface, the rate of work of the external forces differs from the rate of storage of the total energy (the strain energy and the kinetic energy) by the rate of work done in moving the singular surface. Hence, the corresponding continuum theory is capable of modeling dissipative behavior associated with phase transformations which has potential applications in the design ofadaptive structures. The present work indicates that this dissipative behavior is characterized by a material function, called the driving-traction-response function, which is uniquely determined by the strain energy potential of the material. The driving-traction-response function vanishes identically if and only if the Piola-Kirchhoff stress-response function depends upon the deformation gradient linearly.  相似文献   
85.
OBJECTIVE: Ischaemic preconditioning protects myocardium from infarction if the reperfusion interval between the brief and prolonged ischaemic intervals is less than 1 h. In anaesthetised rabbits acadesine (5-amino-4-imidazolecarboxamide riboside, AICAR), an adenosine enhancer which increases tissue adenosine during ischaemia, prolongs the window of protection to 2 h. The aim of this study was to try to determine the maximum extension of this window of protection, using chronically instrumented, unsedated rabbits. METHODS: Rabbits were instrumented with a balloon occluder around a major branch of the left coronary artery for reversible coronary occlusion. Five to seven days after surgery all animals underwent a 30 min coronary occlusion. Animals were randomised to one of seven groups: (1) No additional treatment (control); (2) Ischaemic preconditioning with 5 min regional ischaemia followed by 10 min reperfusion before the 30 min coronary occlusion; (3) and (4) Ischaemic preconditioning followed by 2 or 4 h of reperfusion before the 30 min occlusion, respectively; (5) Treatment with acadesine (2.5 mg.kg-1.min-1 intravenously for 5 min and then 0.5 mg.kg-1.min-1 beginning 45 min before and continuing until 30 min after release of the 30 min occlusion) without ischaemic preconditioning; (6) and (7) Treatment with the higher dose of acadesine for 5 min beginning 35 min before the 5 min ischaemic period, and then the lower dose continuing until 30 min after release of the 30 min coronary occlusion in rabbits with 4 or 6 h reperfusion intervals, respectively. RESULTS: Rabbits with ischaemic preconditioning with 10 min reperfusion preceding the 30 min coronary occlusion (group 2) had only 5.6(SEM 1.1)% infarction of the ischaemic zone. Ischaemic preconditioning followed by 2 h reperfusion (group 3) offered continued protection [18.2(2.2)% infarction] as compared to control animals [37.7(2.6)% infarction]. However, protection waned if ischaemic preconditioning was followed by 4 h reperfusion (group 4) [36.7(3.0)% infarction]. Additionally, treatment with acadesine alone did not modify infarct size (group 7) [39.5(4.0)%], but acadesine largely restored the protection of ischaemic preconditioning despite a 4 h reperfusion interval (group 5) [20.4(3.0)% infarction, P < 0.01 v control]. However, when reperfusion was extended to 6 h (group 6) acadesine could no longer restore protection [36.2(0.9)% infarction]. CONCLUSIONS: The protection afforded by a 5 min ischaemic preconditioning period lasts from 2 to 4 h in the awake, unsedated rabbit, and acadesine can extend the duration of this window of protection to at least 4 h but not to 6 h.  相似文献   
86.
BACKGROUND AND OBJECTIVE: The use of topical anesthetic cream in the periorbital region may be of clinical value. The potential for toxic effects from such use has not been studied in a controlled manner. This study was performed to evaluate the potential ocular toxicity of anesthetic cream topically applied to the eyelid in an animal model. MATERIALS AND METHODS: Ten rabbits underwent periorbital eutectic mixture of local anesthetics (EMLA) (2.5 percent lidocaine and 2.5 percent prilocaine) application and were observed for evidence of gross or microscopic ocular toxicity. Baseline external and anterior segment examinations were performed, including biomicroscopy and fluorescein staining, after which a standard quantity of EMLA cream (0.75 g) was applied along the upper eyelid and covered with an occlusive dressing. After 1 hour of treatment, the eyelid and anterior segment were examined for evidence of adverse reaction. The eyelids were excised and examined histopathologically. RESULTS: No significant adverse effects were noted on external lid and anterior segment examination. The histopathologic findings were within normal limits. CONCLUSIONS: This study suggests that external application of EMLA cream to the eyelid does not induce local toxicity in the rabbit model. The external application of EMLA cream may be safe in the periorbital region.  相似文献   
87.
Semantic priming in word pronunciation was examined at 5 stimulus onset asynchronies (SOAs) in 75 medicated and 25 unmedicated people with schizophrenia (SCZ) and in 10 depressed and 28 normal controls. At SOAs  相似文献   
88.
The effects of the intrathecal perispinal administration of adrenergic agonists on the characteristics of frequency, duration, and vigor of pelvic thrusting displayed by male rats during copulation was assessed by an accelerometric technique. A different dose of one drug (noradrenaline, clonidine or isoproterenol) and saline as control was administered at the lumbosacral level of the spinal cord to sexually active male rats in tests of sexual behavior performed at weekly intervals. The intrathecal administration of noradrenaline (alpha-adrenoceptor agonist) increased the frequency of pelvic thrusting in mount and intromission responses, whereas both the alpha 2-adrenoceptor agonist clonidine (25 micrograms) and the beta-adrenoceptor agonist isoproterenol (40 micrograms) reduced the frequency of pelvic thrusting in these responses as compared to values obtained under the intrathecal administration of saline. On the other hand, the duration of the thrusting trains and the potency or vigor of pelvic thrusting in mounts and intromissions did not differ from values obtained under saline treatment. These findings indicate a possible participation of noradrenaline in the modulation of the spinal mechanisms involved in the generation of rhythmic pelvic thrusting performed by the male rat during copulation.  相似文献   
89.
Administered at a suitably low dose, the toxin streptozotocin (STZ) can trigger an autoimmune process leading to destruction of the beta-cells of the pancreatic islets. In this study, we examined specific immunological reactions in mice before and during the development of STZ-induced autoimmune diabetes. We now report that the development of spontaneous autoantibodies to insulin can serve as a marker of susceptibility to a low dose of STZ. Susceptible male mice of the C57BL/KsJ strain manifested such anti-insulin antibodies, and resistant female mice did not. Administration of a low dose of STZ (five daily doses each of 30 mg/kg) induced transient hyperglycemia approximately 20-30 days later, which temporarily remitted but was followed by intractable diabetes approximately 2.5 months later. The diabetogenic process triggered by the low dose of STZ was associated with an increase in the level of anti-insulin antibodies bearing the Dana and Micha (DM) idiotype, later followed by the appearance of anti-idiotypic antibodies that peaked before the onset of diabetes. Antibodies and T-cells reactive to hsp60 (heat shock protein) were triggered by the low-dose STZ administration and persisted throughout the period that preceded clinical diabetes. T-cells reactive to the p277 peptide of hsp60 were also observed. Finally, active immunization to hsp60 caused transient hyperglycemia by itself and also aggravated the hyperglycemia induced by low-dose STZ. Thus, autoantibodies to insulin can indicate susceptibility to a toxic trigger of diabetes, and a low dose of a toxin can activate the insulin and hsp60 autoimmunity that has been detected previously in the spontaneous autoimmune diabetes of NOD strain mice.  相似文献   
90.
We investigated whether changes in iron metabolism and the transferrin receptor (TRF-R) expression were involved in the antileukaemic effects of arabinoside cytosine (ara-C). Treatment with 100 nM ara-C for 48h reduced thymidine uptake and increased the surface expression of the TRF-R on leukaemic blasts derived from 13/16 (81%) patients and on the HL-60 and U-937 cell lines. Whereas intracellular non-haem iron was strongly depleted 24 h after ara-C addition, TRF-R up-regulation and recovery of intracellular non-haem iron concentration occurred together after a longer exposure of the cultured cells to the drug. Since iron is an essential regulator of cell proliferation we have evaluated the effects of the combination between ara-C and the iron chelator desferioxamine (DSF) on the growth of HL-60 and U-937 cells. We found that desferioxamine strongly potentiated the effects of ara-C on leukaemic cell growth inhibition and apoptosis. This is the first report of a positive interaction between ara-C and an iron chelator in terms of antileukaemic effects.  相似文献   
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