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Florian A Kagerer Jeff J Summers Winston D Byblow Bruce Taylor 《Movement disorders》2003,18(8):919-927
In 6 patients with Parkinson's disease (PD) and 6 age-matched controls, transcranial magnetic stimulation was applied at 56 regions over the motor cortex and premotor cortex of each hemisphere, with the first dorsal interosseous (FDI) muscle of both hands activated at 15% maximum voluntary contraction during stimulation. For each site, motor evoked potential (MEP) landmarks were recovered, including MEP amplitude, MEP onset latency, and silent period duration. Scaled MEP amplitudes were used to construct individual cortical maps of the FDI muscles. The maps revealed an anterior displacement of the muscle representation in PD patients. This anterior shift over motor cortical areas may reflect increased contributions of corticocortical connections between motor cortex and premotor cortical areas, possibly enhanced by the visual feedback aspect of the task. These alterations may reflect adaptations to the impairments in striatocortical circuits in PD. 相似文献
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G W Summers 《Archives of otolaryngology--head & neck surgery》1991,117(11):1237-1241
Cervical exploration was performed in 106 patients with primary hyperparathyroidism and in 19 patients with chronic renal failure. Initial exploration for primary hyperparathyroidism was successful in 97% of the cases. Single adenomas were found in 84, double adenomas in six, and multiple-gland hyperplasia in 12 patients. Two of the four patients in whom cervical exploration failed were ultimately given the diagnosis of benign familial hypocalciuric hypercalcemia. Thirteen adenomas were ectopic. Preoperative thallium-technetium scans and ultrasound correctly localized only 63% of the adenomas. Only 45% of the ectopic adenomas were correctly localized. All four glands should be examined at initial exploration. Because of the occurrence of double adenomas, contralateral exploration is always indicated regardless of whether an enlarged gland and a normal one are found on the first side. All enlarged parathyroids should be removed when dealing with single or multiple adenomas; subtotal parathyroidectomy (3 1/2 glands) should be performed in multiple-gland hyperplasia. Frozen section confirmation of excised parathyroid tissue is essential. If exploration is unsuccessful, ectopic locations such as the retroesophageal areas, thymus, anterior and posterior mediastinum, carotid sheath, and thyroid lobe must be searched carefully. Preoperative localization studies are not as reliable as an experience parathyroid surgeon. 相似文献
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R. S. Summers B. Summers S. Rawnsley L. Hurwitz 《Journal of clinical pharmacy and therapeutics》1987,12(3):181-186
Education for and the practice of Clinical Pharmacy in South Africa have been neglected. This paper describes one attempt to improve matters. An initial survey of pharmacies, pharmacists and other staff in a small group of private hospitals determined the level of Clinical Pharmacy organization and services. The results were used to design a Clinical Pharmacy (training) Programme for selected pharmacists in the group. The programme consisted of six units, each of which was presented in at least a full-day session, with strong audiovisual support, small group discussion and rigorous exercises. During and after each session, implementation and application in the respective hospitals were monitored, as were participants' reactions. Clinical Pharmacy services increased markedly as a result of the programme, as did job satisfaction and motivation among most of the participating pharmacists. 相似文献
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Paul E. Summers Abhir H. Bhalerao David J. Hawkes 《Journal of magnetic resonance imaging : JMRI》1997,7(6):950-957
During the last decade, the quality of MR angiograms has risen substantially and their clinical utility has been demonstrated progressively. This acceptance has created a need for tools with which to summarize and display the information available. We have used a model-based segmentation technique to extract vascular morphology and local flow parameters from phase contrast MR angiograms. A multiresolution data structure is used as the basis of recursive decision-making to identify regions of blood flow. The resulting data representation allows more efficient data handling in subsequent processing and visualization and is directly applicable to the creation of a connected graph model of vascular regions. We describe this flow feature extraction algorithm and demonstrate the utility of the results. 相似文献
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A 14-year-old girl with painful scoliosis was found to have an osteoid osteoma involving the body of the left seventh rib. Excision of the tumor was facilitated by intraoperative bone scanning that precisely located its position. Following surgery, preoperative pain was completely relieved and the spinal curvature had partially regressed. The importance of early diagnosis and excision of tumors is emphasized to prevent the establishment of a permanent structural scoliosis. 相似文献
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Chicks with genetically elevated renal arginase activity were fed crystalline amino acid diets varying in ornithine concentration (0, 1 or 2%) to assess the potential for precursor regulation of polyamine synthesis. Renal arginase and renal and hepatic ornithine decarboxylase activities fell when ornithine was fed. Renal and hepatic ornithine concentrations rose while putrescine concentrations varied quadratically with ornithine feeding. Spermidine and spermine concentrations were not affected by diet. It was concluded that ornithine synthesized in vivo was a more potent stimulator of polyamine synthesis than ornithine of dietary origin. 相似文献
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BACKGROUND: Prior treatment with local hyperthermia has been shown to prevent mast cell degranulation and leucocyte histamine release, and to reduce mortality and cellular infiltrates in a model of acute lung injury. Local hyperthermia is effective in reducing the symptoms of the common cold and perennial and seasonal allergic rhinitis, nasal patency also being improved in rhinitis. It is possible that these effects are mediated by common anti-inflammatory mechanisms, and that this treatment may be effective in the treatment of asthma. The effect of prior local hyperthermia on the response to exercise challenge and histamine bronchoprovocation was therefore examined. METHODS: In a randomised, double blind, placebo controlled, crossover study, 10 asthmatic subjects with exercise induced asthma used machines delivering 40 1/minute of fully humidified air at either 42 degrees C (active treatment) or 31 degrees C (placebo treatment) for 30 minutes' tidal breathing. For each pretreatment, at two week intervals they underwent exercise challenges starting one and 24 hours after starting the inhalations. After a further two weeks the protocol was repeated with histamine substituted for the exercise challenges. RESULTS: The mean (SE) maximum percentage fall in forced expiratory volume in one second (FEV1) was significantly lower one hour after treatment with air at 42 degrees C (30.8% (3.1%)) than after treatment with air at 31 degrees C (22.3% (2.9%)). There was no significant effect on exercise challenge at 24 hours, or on histamine challenge at either time point, though there were nonsignificant trends towards protection with exercise at 24 hours and with histamine at one hour. CONCLUSION: In asthmatic subjects the response to exercise challenge is significantly attenuated one hour after treatment with local hyperthermia. This treatment warrants further investigation in the treatment of clinical asthma and other inflammatory disorders. 相似文献