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71.
Modulating effects of posttraining epinephrine on memory: Involvement of the amygdala noradrenergic system 总被引:5,自引:0,他引:5
These experiments examined the effects, on retention, of posttraining intra-amygdala administration of norepinephrine (NE), and propranolol. Rats were trained on a one-trial step-through inhibitory avoidance task and tested for retention 24 h later. Injections were administered bilaterally (1.0 microliter/injection) through chronically-implanted cannulae. Low doses of NE (0.1 or 0.3 microgram) administered shortly after training enhanced retention while higher doses (1.0 or 5.0 micrograms) were ineffective. Retention was not affected by NE administered 3 h after training. The effect of intra-amygdala NE on retention is blocked by simultaneous administration of propranolol (0.2 microgram). This finding suggests that the memory-enhancing effect of NE may be mediated by beta-receptors. Posttraining intra-amygdala NE also attenuated the retention deficit produced by adrenal demedullation. Further, intra-amygdala injections of propranolol (0.2 microgram) blocked the enhancing effect, on retention, of posttraining s.c. injections of epinephrine. These findings suggest that activation of noradrenergic receptors in the amygdala may be involved in memory processing and may play a role in the memory-modulating effect of peripheral epinephrine. 相似文献
72.
S. Ahmed A. L. Sparnon J. P. Savage H. A. Boucaut A. J. Smith 《ANZ journal of surgery》1986,56(9):675-680
One hundred and one children over 1 year of age have had surgery for pelviureteric obstruction over an 11 year period. The common clinical features were abdominal pain, urinary infection or haematuria, but number presented as an incidental finding. Less commonly, the patients presented with an abdominal mass or with hypertension. The diagnosis was usually made on intravenous pyelography (IVP) but in the latter part of the series, renal nuclide scan (RNS) and ultrasonography (US) were preferred. Ninety–three patients had unilateral pyeloplasty, three had bilateral pyeloplasty and five had nephrectomy or heminephrectomy. Whereas initially nephrostomy drainage was used in the majority of patients after pyeloplasty, trend away from nephrostomy evolved in the latter part of the series. With experience, the incidence of postoperative complications was also reduced and there was reduction in the period of hospitalization. Clinical results were consistently satisfactory. Postoperative assessment after pyeloplasty was made by IVP and/or RNS and also US. A review of these investigations showed that RNS provided more factual information of the result when compared with the IVP. 相似文献
73.
We observed three children, aged 1 year 8 months to 9 years 7 months, in whom herpes simplex blepharoconjunctivitis resolved promptly without treatment. A fourth child, 8 years old, developed probable toxic manifestations from topical vidarabine. These manifestations, as well as the blepharoconjunctivitis, resolved when the medication was discontinued. Herpes simplex ocular infection without corneal involvement in children is usually benign and self-limited. 相似文献
74.
P M Battey J T Fulenwider R B Smith L G Martin M T Stewart G D Perdue 《Southern medical journal》1987,80(4):479-482
Peripheral arterial thromboembolism and thrombosis of arterial grafts continue to threaten viability of extremities. Percutaneous intra-arterial thrombolysis (IAT) and angiodilatation have afforded limb salvage in some of these patients. Proper patient selection appears to be the hallmark of success with IAT. During a recent three-year period, we used IAT in 32 extremities in 28 patients who had acute arterial insufficiency. Before IAT, 16 extremities were painful at rest, and 16 had incapacitating claudication. The overall success rate was 38%, but some degree of thrombolysis occurred in 88%. Limb salvage was achieved in 27 of 32 extremities (84%). Only five of 17 limbs (29%) with arterial graft thrombosis required no operation or an operation of lesser magnitude than predicted before IAT. Of six extremities with native arterial embolism, four (67%) were completely cleared with IAT. Major complications occurred in eight cases (25%), with two IAT-related deaths (6%). This study suggests that IAT is best reserved for individuals with acute limb ischemia caused by arterial embolus, those whose degree of ischemia would tolerate a 24-hour trial of IAT, and those whose femoral or tibial runoff is not likely to require remedial operation. 相似文献
75.
Dipankar Nandi Helen Smith Sarah Owen Carole Joint John Stein Tipu Aziz 《Journal of clinical neuroscience》2002,9(5):557-561
Central post stroke pain is often difficult to manage satisfactorily with conventional treatment modalities for pain. In the last decade functional neurosurgery has offered hope with motor cortex stimulation achieving significant alleviation of pain in some patients. Unfortunately this has led to the neglect of chronic stimulation of deep grey matter as another modality of treating this condition. In this article we present our experience with motor cortex stimulation and that with deep grey matter stimulation in patients with post stroke pain. We argue that both modalities have a significant role and that what is required are better methods of identifying particular patients who are more likely to respond to one or the other. 相似文献
76.
Human papillomavirus genotype distribution in low-grade cervical lesions: comparison by geographic region and with cervical cancer. 总被引:13,自引:0,他引:13
Gary M Clifford Rashida K Rana Silvia Franceschi Jennifer S Smith Gerald Gough Jeanne M Pimenta 《Cancer epidemiology, biomarkers & prevention》2005,14(5):1157-1164
Low-grade squamous intraepithelial lesions (LSIL) associated with certain human papillomavirus (HPV) genotypes may preferentially progress to cervical cancer. HPV genotyping may thus have the potential to improve the effectiveness of screening programs and to reduce overtreatment. LSIL cases (n = 8,308) from 55 published studies were included in a meta-analysis. HPV genotype distribution was assessed by geographic region and in comparison with published data on cervical squamous cell carcinoma (SCC). HPV detection in LSIL was 80% in North America but less than 70% in other regions, most likely reflecting regional differences in LSIL diagnosis. Among 5,910 HPV-positive LSILs, HPV16 was the most common genotype (26.3%) followed by HPV31 (11.5%), HPV51 (10.6%), and HPV53 (10.2%). HPV-positive LSILs from Africa were 2-fold less likely to be infected with HPV16 than those in Europe, and HPV-positive LSILs from North America were more likely to be infected with HPV18 than those from Europe or South/Central America. Interpretation for rarer genotypes was hampered by variation in HPV testing methodology. SCC/LSIL prevalence ratios indicated that HPV16 was 2-fold and HPV18 was 1.5-fold more common in SCC than in HPV-positive LSIL, thus appearing more likely to progress than other high-risk genotypes (SCC/LSIL prevalence ratios between 0.05 and 0.85). HPV53 and HPV66 showed SCC/LSIL ratios of 0.02 and 0.01, respectively. HPV genotype distribution in LSIL differs from that in cervical cancer, highlighting the importance of HPV genotype in the risk of progression from LSIL to malignancy. Some regional differences in the relative importance of HPV genotypes in LSIL were noted. 相似文献
77.
Glenn Roberts John Somers Jocelyn Dawe Rowena Passy Carly Mays Graham Carr David Shiers Jo Smith 《Early intervention in psychiatry》2007,1(2):168-176
Aims: On the Edge is a mental health education programme designed to support early intervention by increasing knowledge and understanding of early psychosis, reducing the stigma associated with mental health issues and improving awareness of avenues of help. The target audience was young people aged 14–22 years in schools and colleges. Methods: An interactive drama programme was developed through collaborative working across psychiatry, applied drama and those with direct experience of psychosis. A national tour engaged 2500 students in 71 performances that took place in 51 schools and colleges. The programme was evaluated against its aims with data collected both during and after the tour. Results: Quantitative and qualitative evaluation found significant gains with respect to all three aims. Thirty‐one schools developed supportive links with local mental health services. Conclusions: This programme shows the value and effectiveness of delivering health education on early psychosis through the medium of applied drama, and offers a model for a programme that can be incorporated into early intervention services. Lessons learned through delivering this programme are a valuable contribution towards future developments of mental health education programmes for schools. 相似文献
78.
Ronald Martin Jaime Williams Thomas Hadjistavropoulos Heather D Hadjistavropoulos Michael MacLean 《Revue canadienne de recherche en sciences infirmières》2005,37(2):142-164
The literature suggests that pain in the elderly, especially among seniors with dementia, is under-assessed and under-treated.This qualitative study solicited the perspectives of seniors, front-line nursing staff, nursing-home administrators, and informal caregivers of seniors with dementia on the current status of pain assessment and management. The views of these participants complement the research findings reported in the literature. While some of their explanations and potential solutions concerning under-treatment of pain in seniors echo views that have been presented in the literature, the participants also pointed to factors and avenues that have been given less formal consideration (e.g., systemic barriers to effective assessment and treatment of pain).They also highlighted the need for pain-control strategies beyond medication. The implications of these findings are discussed. 相似文献
79.
K J Meador J L Thompson D W Loring A M Murro D W King B B Gallagher G P Lee J R Smith H F Flanigin 《Neurology》1991,41(6):869-872
Although there has been extensive examination of the behavioral and physiologic correlates of hippocampal theta activity in animals, the human literature consists of a single case study. We investigated the differential effects of four behavioral states on human hippocampal theta activity in 16 epilepsy surgery patients. Behavioral conditions included resting eyes closed (RC), resting eyes open (RO), eyes open with auditory word activation (AW), and eyes open with visuospatial activation (VS). Hippocampal theta activity decreased during both RO and VS compared to both RC and AW. There were reciprocal changes in delta activity. Comparisons of RO to VS and of RC to AW were nonsignificant. The results demonstrate state-specific changes in human hippocampal theta and are consistent with the animal literature that relates hippocampal theta to sensorimotor integration and forebrain volitional mechanisms. 相似文献
80.
The rat class 3 aldehyde dehydrogenase gene (ALDH3A1) is expressed constitutively or by xenobiotic induction depending on the tissue in which it occurs. Although the mechanism that mediates inducible expression has been well characterized, relatively little is known about constitutive regulatory mechanisms. Previous ALDH3A1 promoter analyses have indicated that primary regulatory regions within the ALDH3A1 5' flanking region exert similar effects on both constitutive and inducible ALDH3A1 expression. However, promoter gene analyses that served as the basis of early work were limited by the lack of sufficient 5' flanking region sequence. To gain a more complete picture of how the 5' flanking region regulates both modes of expression, we have subcloned an 8.0-kilobase (kb) fragment from the 5' flanking region of the ALDH3A1 gene and subjected it to reporter gene analyses. We found a region located between 4.8 and 7.8 kb upstream of the noncoding first exon that drives strong ALDH3A1 reporter activity. This region contains xenobiotic response element consensus sequences that mediate constitutive and inducible ALDH3A1 reporter gene expression. Using the new generation of ALDH3A1 reporter constructs, we were unable to confirm the presence of a negative regulatory region that was apparent in previous studies using a shorter fragment of the 5' flanking region. We also demonstrate that 3-methylcholanthrene induces ALDH3A1 expression above high constitutive background in corneal epithelial cells. 相似文献