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Such research evidence as exists on effective drug strategies in prevention and education draws attention to the importance of involving parents along with other community agencies and school governors. Much depends nevertheless on the way in which 'involvement' is interpreted and the assumptions that are made about parents' knowledge of drugs and drug education as well as their attitudes to drug issues. As the age of initial experimentation and contact with drugs continues to fall, the importance of enskilling parents to support drug education programmes for 5 year olds and upwards continues to rise. This paper reports the first wide ranging survey of parents' knowledge of drugs and drug issues across an entire English county embracing younger as well as older children. The need for more coordinated, informed and systematic guidance to parents is established.  相似文献   
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The goals of this study were to investigate muscle fatigue in patients with multiple sclerosis (MS), and to determine the relationships between muscle fatigue, clinical status, and perceived fatigue. The fatigability of the anterior tibial muscle was quantitated in patients and controls during 9 min of intermittent stimulation (used to eliminate central sources of muscle fatigue). During exercise, the decline in tetanic force, phosphocreatine, and intracellular pH was greater in patients than in controls. The compound muscle action potential amplitude did not decrease during exercise, indicating that there was no failure of neuromuscular transmission during fatigue. Thus, the excessive fatigue in MS developed from sources beyond the muscle membrane. Following exercise, the recovery of tetanic force was delayed in patients (a pattern that suggests abnormal excitation–contraction coupling), whereas the recovery of metabolites was complete in both groups. Muscular fatigue was correlated with clinical disability but not with perceived fatigue. These results suggests that fatigue in MS has both central (perception, upper motor neuron dysfunction) and peripheral (impaired metabolism and excitation–contraction coupling) components.© 1995 John Wiley &Sons, Inc.  相似文献   
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We have devised assays to detect both circulating alloantibodies to platelets (indirect assay) and platelet-association IgG and IgM (direct assay) using a flow cytometric technique. A variety of patients with immune thrombocytopenia were studied. Employment of a confocal lens in the flow cytometer increased the discrimination power of the instrument. Patients with autoimmune thrombocytopenia (idiopathic thrombocytic purpura [ITP], systemic lupus erythematosus (SLE), lymphoma, leukemia, and drug-induced thrombocytopenia showed a significant increase in platelet-associated antibody. Circulating antibodies to platelets (alloantibodies) were demonstrated in cases of platelet refractoriness and neonatal isoimmune purpura. Day-today precision of the assays ranged from 3% to 6% (coefficient of variation). No interference was shown in the presence of hemoglobin (5 g/L), triglycerides (10 g/L), or polyclonal and monoclonal immunoglobulinemia (50 g/L: IgG, IgA, IgM). The sensitivity of the direct assay was 500 attograms of IgG or IgM platelet.  相似文献   
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PURPOSE: To identify the ocular features of the chromosome 22q11.2 deletion syndrome and to provide ophthalmologic examination recommendations for affected patients. METHODS: Ocular abnormalities were evaluated prospectively in patients with 22q11.2 deletion at the Children's Hospital of Philadelphia between 1997 and 1999. RESULTS: Ninety patients with confirmed 22q11.2 deletion were examined. Posterior embryotoxon was found in 49%, tortuous retinal vessels in 34%, eyelid hooding in 20%, strabismus in 18%, ptosis in 4%, amblyopia in 4%, and tilted optic nerves in 1%. CONCLUSIONS: The high incidence of ocular conditions that can potentially affect visual development suggest that children with 22q11.2 deletion should undergo a comprehensive eye examination upon diagnosis of the condition with follow-up as indicated by the findings in each case. In addition, knowledge of the ocular findings, in conjunction with certain cardiac, otolaryngologic, immunologic, and other systemic findings, may alert physicians to the possibility of a chromosome 22q11.2 deletion.  相似文献   
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By using stereotaxic surgical techniques, ventral mesencephalic tissues from aborted human fetuses of 8 to 10 weeks' gestational age were implanted unilaterally into the striata in two patients with advanced Parkinson's disease. The patients were treated with a cyclosporine, azathioprine, and steroid regimen to minimize the risk for graft rejection. They were examined for 6 months preoperatively and 6 months postoperatively and continued to receive the same doses of antiparkinsonian medication. There were no significant postoperative complications. No major therapeutic effect from the operation was observed. However, in the clinical tests, both patients showed small but significant increases of movement speed for repeated pronation-supination, fist clenching, and foot lifting. The rate of walking also increased in the one patient tested. For both patients, there was an initial worsening postoperatively, followed by improvement vs preoperative performance at 1 to 3 months. Both patients also showed significant improvement in the magnitude of response to a single dose of levodopa (L-dopa), but there was no increase in the duration of drug action. The motor readiness potential increased in both patients postoperatively, primarily over the operated hemisphere. Neurophysiological measurements also showed a more rapid performance of simple and complex arm and hand movements on the side contralateral to transplantation in one patient at 5 months postoperatively. Positron emission tomography demonstrated no increased uptake of 6-L-(18F)-fluorodopa in the transplanted striatum at 5 and 6 months. Taken together, these results suggest that the fetal nigral implants may have provided a modest improvement in motor function, consistent with the presence of small surviving grafts. Although our results support further scientific experimentation with transplantation in Parkinson's disease, widespread clinical trials with this procedure are probably not warranted at this time.  相似文献   
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