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51.
We describe a technique for conducting a CT-guided biopsy of the brachial plexus region, report two illustrative cases, discuss potential complications, and conclude that, in selected cases, biopsy of lesions in the region of the brachial plexus can be performed safely with CT guidance.  相似文献   
52.
The involvement of brain monoamines in learning and memory in developing rats was studied by comparing the effects of 3 different noradrenergic neurotoxin treatments. Two experimental groups of male Sprague-Dawley rat pups were injected systemically with 50 micrograms/g of N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) either on the day of birth or on postnatal days 17-18. Rats in the third experimental group were injected systemically with 60 micrograms/g of 6-hydroxydopa (6-OHDOPA) on postnatal days 0 and 2. Control littermates received vehicle. The animals were trained on an inhibitory avoidance task on postnatal days 27-29 and tested for retention 24 h later. The drug treatments produced comparable depletion of norepinephrine in the hippocampus and frontal cortex. 6-OHDOPA, but neither DSP-4 treatment, significantly elevated brainstem concentrations of norepinephrine and serotonin. In addition, 6-OHDOPA, but not DSP-4, significantly impaired retention of the inhibitory avoidance task. The impairment did not reflect insensitivity to the footshock used in training: both neonatal drug treatments tended to lower, not raise, footshock thresholds, as measured by a flinch test. High affinity choline uptake was not affected by either neonatal drug treatment in any of the brain areas examined. Thus, the 6-OHDOPA-induced behavioral deficit did not involve altered acetylcholine function. The results implicate brainstem monoamines in the modulation of learning and memory during development.  相似文献   
53.
Many concerns surround the preparation of a person with spina bifida for a successful transition into adult life and responsibilities. A model of intervention must be based on developmental concerns and timely issues from infancy through all stages of development to young-adult life. This article discusses, within a developmental framework, issues of transition in relation to physical, social, emotional, and educational/vocational needs; it also presents a conceptual framework for the transition into adulthood. Guidelines were developed by incorporating expected outcomes of people with spina bifida and using a philosophical framework that encompasses the achievement of a balance among dependence, independence, and interdependence. This model is based on developmental issues from infancy through all stages of development to young-adult life. Using this framework for care, the rehabilitation nurse can feel confident that the needs of clients with spina bifida and similar chronic conditions are being met.  相似文献   
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A 38-year-old man developed parkinsonism that progressed to Hoehn and Yahr stage 5 within 4 years of onset. Response to ropinirole deteriorated, levodopa was not tolerated, and subthalamic nucleus stimulation has provided only partial relief of symptoms. He reported heavy use of Ecstasy through most of his twenties and thirties. His neurological problems may be unrelated to his drug use, but it is also possible they represent an idiosyncratic reaction.  相似文献   
57.
大狼毒三萜类化学成分的研究   总被引:3,自引:0,他引:3  
曹东  苏亚伦  杨峻山 《药学学报》1992,27(6):445-451
自大戟科(Euphorbiaceae)植物大狼毒(Euphorbia nematocypha Hand—Mazz)根的乙醇提取物的苯溶解部分,经20%AgNO3硅胶层析,分离得到七个三萜类成分。根据光谱(IR,EIMS,1H—NMR和13C—NMR)和化学方法,确定其中一个化合物为新化合物,命名为大狼毒醇(nematocyphol,Ⅳa),其它化合物为已知物:印度荆芥醇乙酸酯(nepehinol acetate Ⅰ),日尔曼醇乙酸酯(germanicol acetate Ⅱ),大戟醇(euphol,Ⅲ),蒲公英醇(taraxasterol,Ⅴa),24-亚甲基环阿尔廷醇(24-methylenecycloartanol,Ⅴa)和印度荆芥醇(nepehinol,Ⅶa)。这些化合物均为首次从大狼毒中得到。  相似文献   
58.
Leonard A Cole 《JPHMP》2003,9(5):357-360
Among the 22 confirmed or suspected cases of anthrax during the bioterrorism incidents in 2001, all but two seemed traceable to spores from threat letters. Although no anthrax spores were found in the environments frequented by two females who died of the disease, a suspicion persists that the deaths were somehow related to the mail. This study assesses the spread and persistence of a mock biological agent from a source-letter to other mail and to a receiving mailbox. Successive placement and removal of letters were found to reduce the number of residual bio-agent particles in a mailbox. This suggests that a sweeping action is taking place that can affect the quantity of bio-agent remaining. The exercise supports the possibility that the two females were exposed to spores on mail that had been in their mailboxes although no trace of spores could later be found in their boxes.  相似文献   
59.
Previous studies in rats using the Morris water maze suggested that the processing of spatial information is modulated by corticosteroid hormones through mineralocorticoid and glucocorticoid receptors in the hippocampus. Mineralocorticoid receptors appear to be involved in the modulation of explorative behaviour, while additional activation of glucocorticoid receptors facilitates the storage of information. In the present study we used the water maze task to examine spatial learning and memory in mice homozygous and heterozygous for a targeted disruption of the glucocorticoid receptor gene. Compared with wild-type controls, homozygous and heterozygous mice were impaired in the processing of spatial but not visual information. Homozygous mutants performed variably during training, without specific platform-directed search strategies. The spatial learning disability was partly compensated for by increased motor activity. The deficits were indicative of a dysfunction of glucocorticoid receptors as well as of mineralocorticoid receptors. Although the heterozygous mice performed similarly to wild-type mice with respect to latency to find the platform, their strategy was more similar to that of the homozygous mice. Glucocorticoid receptor-related long-term spatial memory was impaired. The increased behavioural reactivity of the heterozygous mice in the open field points to a more prominent mineralocorticoid receptor-mediated function. The findings indicate that (i) the glucocorticoid receptor is of critical importance for the control of spatial behavioural functions, and (ii) mineralocorticoid receptor-mediated effects on this behaviour require interaction with functional glucocorticoid receptors. Until the development of site-specific, inducible glucocorticoid receptor mutants, glucocorticoid receptor-knockout mice present the only animal model for the study of corticosteroid-mediated effects in the complete absence of a functional receptor.  相似文献   
60.
SARS-CoV isa newly identified coronavirus that causes severe acute respiratory syndrome (SARS). Currently, there is no effective method available for prophylaxis and treatment of SARS-CoVinfections. In the present study, the influence of small interfering RNA (siRNA) on SARS-CoV nucleocapsid (N) protein expression was detected in cultured cells and mouse muscles. Four siRNA expression cassettes driven by mouse U6 promoter targeting SARS-CoV N gene were prepared, and their inhibitory effects on expression of N and enhanced green fluorescence protein (EGFP) fusion protein were observed.  相似文献   
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