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排序方式: 共有1802条查询结果,搜索用时 15 毫秒
81.
82.
Sjögren K Fochsen G Josephson M Lagerström M 《International journal of nursing studies》2005,42(7):751-758
Based on two research projects in Sweden during the 1990s, the aim of this study was to identify former nursing personnel's main reasons for leaving nursing care, and to find out under what circumstances they would consider returning. Two open-ended questions in a questionnaire were analysed. The results showed that different aspects of working conditions, mainly working schedule, management and status of profession were the dominating reasons both for leaving and considering a return. The findings indicate that interventions required for retaining personnel in nursing care need to be addressed both at the political and at the local level. 相似文献
83.
1. Eleven cases of surgical repair of acute tears of the capsule, anterior talo-fibular, and calcaneo-fibular ligaments of the ankle in young athletic individuals are reported. 2. Diagnosis was made by clinical examination and stress X-rays and confirmed by arthrography in selected cases. All of the ligament ruptures were visualized at surgery. 3. Post-surgery, all of the patients had a stable ankle and were able to return to vigorous athletic endeavors without disability. 4. This study lends support to the impression that surgical repair of severe lateral collateral ankle ligament injuries in young athletic individuals leads to a functionally and mechanically stable ankle able to withstand severe stress without disability. 相似文献
84.
The aim of the present study was to assess the efficacy and effectiveness of the primary prevention program “Everybody's Different” among fifth grade school children. Pre and post measurements were made in both the intervention and control groups regarding body image, weight concern, emotional well-being, attitudes and behaviors associated with disordered eating, self-esteem, anxiety, and depression. The study did not result in any significant improvements regarding self-esteem, eating attitudes, or body image. The prevention program does not seem to be effective for children in grade five in its present form. Further research on and development of primary prevention programs is needed. 相似文献
85.
Hypoxic preconditioning confers long-term reduction of brain injury and improvement of neurological ability in immature rats 总被引:7,自引:0,他引:7
Exposure to preconditioning (PC) hypoxia 24 h before a severe hypoxic-ischemic (HI) insult reduces development of injury in the immature brain. Several protective regimens have proved effective in the short-term but not in the long-term perspective. The aim of the present study, therefore, was to evaluate the PC effect on long-term morphologic and neurologic outcome in the developing brain. Six-day-old rats were subjected to hypoxia (36 degrees C, 8.0% O2; PC/HI group) and sham controls to normoxia (36 degrees C; HI group) for 3 h. Twenty-four hours later, all rats were exposed to cerebral HI produced by unilateral carotid artery occlusion combined with 1 h, 15 min of hypoxia (36 degrees C, 7.7% O2). A cylinder test was used to evaluate forelimb asymmetry to determine sensorimotor function at 4, 6, and 8 wk of age. Spatial/cognitive ability was assessed by Morris water maze trials at 7 wk of recovery. Neuropathologic analysis was performed 8 wk after insult. Brain damage was reduced (p<0.0001) in PC/HI (45.0+/-11.1 mm3) in comparison with HI (159.3+/-12.2 mm3) rats. A bias for using the ipsilateral forelimb in wall movements was observed in the cylinder test in HI compared with PC/HI rats at 4 (p<0.001), 6 (p<0.01), and 8 (p<0.0001) wk of age. Results of the Morris water maze test revealed differences (p<0.0001) in average path length between groups on the third and fourth day of trials. Hypoxic PC before HI reduced brain injury by 72% at 8 wk after the insult and provided long-term improvement of sensorimotor and spatial/cognitive functions. 相似文献
86.
Goyarzu P Malin DH Lau FC Taglialatela G Moon WD Jennings R Moy E Moy D Lippold S Shukitt-Hale B Joseph JA 《Nutritional neuroscience》2004,7(2):75-83
It has been reported that an antioxidant-rich, blueberry-supplemented rat diet may retard brain aging in the rat. The present study determined whether such supplementation could prevent impaired object recognition memory and elevated levels of the oxidative stress-responsive protein, nuclear factor-kappa B (NF-kappaB) in aged Fischer-344 rats. Twelve aged rats had been fed a 2% blueberry supplemented diet for 4 months prior to testing. Eleven aged rats and twelve young rats had been fed a control diet. The rats were tested for object recognition memory on the visual paired comparison task. With a 1-h delay between training and testing, aged control diet rats performed no better than chance. Young rats and aged blueberry diet rats performed similarly and significantly better than the aged control diet group. Levels of NF-kappaB in five brain regions of the above subjects were determined by western blotting assays. In four regions, aged control diet rats had significantly higher average NF-kappaB levels than young animals on the control diet. In four regions, aged blueberry diet rats had significantly lower levels of NF-kappaB than aged control diet rats. Normalized NF-kappaB levels (averaged across regions and in several individual regions) correlated negatively and significantly with the object memory scores. 相似文献
87.
Sjögren J Gustafsson R Wackenfors A Malmsjö M Algotsson L Ingemansson R 《Interactive Cardiovascular and Thoracic Surgery》2004,3(4):666-671
Several authors have reported promising results with vacuum-assisted closure therapy in poststernotomy mediastinitis. The aim of this study was to investigate the hemodynamic outcome following the application of six negative pressures on an open sternotomy wound. Six 70-kg pigs underwent median sternotomy followed by vacuum-assisted closure therapy. Six negative pressures (-50, -75, -100, -125, -150, and -175mmHg) were applied to each pig for 30min each while hemodynamic parameters were measured. An increase in cardiac output was observed at -75mmHg when compared to the other five pressures: -50mmHg (P<0.05; CI 0.12-1.13l/min), -100mmHg (P<0.001; CI 0.34-1.32l/min), -125mmHg (P<0.001; CI 0.51-1.52l/min), -150mmHg (P<0.001; CI 0.50-1.47l/min), and -175mmHg (P<0.05; CI 0.13-1.17l/min). A decrease in systemic vascular resistance was observed at -75mmHg when compared to -125mmHg (P<0.01; CI 108-552dyn.s/cm(5)) and -150mmHg (P<0.01; CI 90-543dyn.s/cm(5)), but not compared to the other pressures. No change (P=ns) was observed in heart frequency, mean arterial pressure or central venous pressure. Our data demonstrates that vacuum-assisted closure therapy of -50 to -175mmHg does not impair the central hemodynamics in a porcine sternotomy model. 相似文献
88.
Loss of heterozygosity on chromosomes 10q, 9p, 17p and 13q in malays with malignant glioma 总被引:3,自引:0,他引:3
Recent advances in neuro-oncology have revealed different pathways of molecular oncogenesis in malignant gliomas including loss of heterozygosity on chromosomal regions harboring tumor suppressor genes. In the present study, we performed polymerase chain reaction-loss of heterozygosity (PCR-LOH) analysis using microsatellite markers to identify loss of heterozygosity on chromosomes 10q, 9p, 17p and 13q in the Malays with malignant gliomas. Of 12 cases with allelic losses, seven (58.3%) cases showed LOH on chromosome 10q, three (25.0%) cases showed LOH on chromosome 9p, four (33.3%) cases showed LOH on chromosome 17p and two (16.7%) cases showed LOH on chromosome 13q. The cases include five (41.7%) cases of glioblastoma multiforme, three (25.0%) cases of anaplastic astrocytoma, three (25.0%) cases of anaplastic oligodendroglioma and one (8.3%) case of anaplastic ependymoma. Four cases showed loss of heterozygosity on more than one locus. Our findings showed that loss of heterozygosity on specific chromosomal regions contributes to the molecular pathway of glioma progression in Malay population. In addition, these data provide useful evidence of molecular genetic alterations of malignant glioma in South East Asian patients, particularly in the East Coast of Malaysia. 相似文献
89.
90.
Tegenthoff M Cornelius B Pleger B Malin JP Schwenkreis P 《Acta neurologica Scandinavica》2004,109(5):330-336
OBJECTIVES: Repetitive synchronized movements lead to short-term plastic changes in the primary motor cortex, which can be assessed by transcranial magnetic stimulation (TMS). Drugs which enhance such plastic changes could be of therapeutical interest, e.g. in patients with cerebral lesions. MATERIAL AND METHODS: We studied the effect of amphetamine on motor performance and plastic changes in the motor cortex as revealed by TMS mapping in healthy humans, who had to train a repetitive synchronized movement over 1 h. RESULTS: Cortical plastic changes observed after 1 h of training were more pronounced with amphetamine, whereas motor performance did not differ between training sessions with and without amphetamine. CONCLUSION: We conclude that amphetamine is able to enhance training-induced motor cortex plasticity. This effect could be due to its known influence on the GABAergic and glutamatergic system, but might also result from its role as an indirect catecholaminergic agonist. 相似文献