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991.
Dissection of the extracranial vertebral artery: report of four cases and review of the literature. 下载免费PDF全文
P Hinse A Thie L Lachenmayer 《Journal of neurology, neurosurgery, and psychiatry》1991,54(10):863-869
Four cases of cervical vertebral artery (VA) dissection are reported. In three patients VA dissection was associated with neck trauma. All patients were young or middle-aged (range 27 to 49 years). In two there was a history of migraine. Pain preceded neurological symptoms from hours to six weeks. Three patients had neurological deficits including elements of the lateral medullary syndrome, and one experienced recurrent transient ischaemic attacks in the vertebrobasilar territory. Angiographic findings included irregular stenosis, occlusion and pseudoaneurysm; in two patients VA abnormalities were bilateral. All patients were treated with anticoagulants and improved. In a review of 28 cases with traumatic dissection and 29 cases with spontaneous dissection of the VA reported in the literature, distinct clinical and angiographic features emerge. Aetiology remains obscure in most cases of spontaneous dissection and management is still controversial. 相似文献
992.
Bipolar disorder is a serious mental illness affecting a large number of Americans. While lithium, the treatment of choice for this disorder, is usually effective, a substantial number of individuals with bipolar disorder are not helped by lithium or are intolerant to its side effects. Consequently, investigators are searching for alternative drugs in order to treat lithium-resistant patients. Although a number of alternative drug treatments have been discussed in the literature, only the anticonvulsants carbamazepine and valproate appear to warrant serious consideration at this time. Future research will further define their roles as antimanic agents. 相似文献
993.
M C Salinsky B S Oken L Morehead 《Electroencephalography and clinical neurophysiology》1991,79(5):382-392
This study was performed to gain a better understanding of EEG frequency analysis test-retest reliability in normal healthy adults, and to evaluate factors which could influence the measured inter-record differences. Nineteen subjects underwent serial EEG recordings at 5 min and 12-16 week intervals. Records were visually edited using a standardized protocol, and FFT frequency analysis performed on segments of 60, 40, or 20 sec total length. Correlation coefficients for broad band features averaged 0.92 over the 5 min retest interval and 0.84 over the 12-16 week interval. There was essentially no difference between correlation coefficients of absolute and relative power features. Coefficients based on 60 sec records were marginally higher than those of 40 or 20 sec records. On the other hand, test-retest percent differences were typically lower for relative as opposed to absolute power features, and 60 sec records showed consistently lower percent differences than did 40 or particularly 20 sec records. Peak alpha frequency and mean frequency were the most stable EEG features at either interval. Montage had significant effects on test-retest differences at the 12-16 week interval. A significant association between intra-record and inter-record variability could not be demonstrated. 相似文献
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G I Rumiantsev T M Khodykina V I Arkhangel'ski? L N Nesterenko 《Gigiena truda i professional'nye zabolevaniia》1991,(6):19-22
In the processing of the waste products of phosphorus containing fertilizer production, several major health-related factors were identified depending on the industrial site's peculiarities: unfavourable microclimate conditions (both cold and heat), relative temperature differences, noise and vibration caused by the equipment, semi-product's, additives' and finished product's dusts, fluorine- and phosphorus-containing substances' affects and poor illumination. The proposed data were used for health-related improvements in the occupational conditions. 相似文献
997.
NTS fallout-induced multiple myeloma in Utah. 总被引:1,自引:0,他引:1
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The contributors propose a selective photometric technique for detection of sodium and potassium cyanides in different washings, sewage, overalls extraction. The technique was based on the formation of a polymetyne dye, and barbituric acid and pyridine reactions. It proved efficient in detecting the cyanides within 0.01-0.054 mg/dm3, 1-100 mg/l, 0.08-1.24 mg/dm3 with deviations not exceeding 23%. Duration of the test was limited to 25-30 min. 相似文献