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91.
92.
作者提出了一种膈神经放电信号的计算机分析方法,用以克服该信号手工分析时存在的问题。计算机通过对膈神经放电信号的采集、数字整流与滤波等处理后,可得到放电的包络图,从中能自动测量一些重要参数。动物实验证实程序能较好地执行这些功能。统计学分析表明,人工测量结果与计算机测量结果之间无显著性差异。 相似文献
93.
神经活素对Pc12细胞作用的初步观察 总被引:1,自引:0,他引:1
从胎脑、颌下腺、肌肉组织中制备神经活素。其性能同脑活素一样:可促进Pc12细胞的突起生长,提高其胞浆内乳酸脱氢酶活性,电泳显示二者有相同的三条带。提示:神经活素有可能替代脑活素应用于临床。 相似文献
94.
95.
László Bajnok Bertalan Kozlovszky József Varga Judit Antalffy Sándor Olvasztó Tamás Fülöp Jr. 《European journal of nuclear medicine and molecular imaging》1994,21(12):1326-1332
Technetium-99m sestamibi was used for functional investigation of the muscle perfusion of lower extremities in 35 patients
with peripheral vascular disease. The aim was to test what useful information could be obtained by additional imaging of the
legs in patients referred for risk stratification with dipyridamole myocardial scanning. Posterior images were acquired over
the thighs and calves after postocclusive reactive hyperaemia and at rest. Inter- and intraextremity ratios and differences
between the stress and rest data were used for the assessment of abnormal circulation. Arteriography was performed in every
case, and surgical procedures or transluminal angioplasty in 31 patients. To estimate diagnostic accuracy, the results of99mTc-sestamibi scintigraphy were compared with those of angiography and the functional consequences of revascularization procedures.
The sensitivity and specificity of99mTc-sestamibi scintigraphy were 55% and 25%, respectively, with an overall accuracy of 50%. Apparently methodological error
was not responsible for these poor results. Instead, a paradoxically high uptake of the radiopharmaceutical in muscles supplied
by significantly stenosed vessels was identified as the main source of both false-negative and false-positive results. This
phenomenon resembles the findings of a previous study involving delayed administration of thallium-201 after exercise. In
conclusion,99mTc-sestamibi scintigraphy has not proved sufficiently reliable to help in the management strategy for patients with peripheral
vascular disease. 相似文献
96.
H Angus-Leppan GA Lambert J Michalicek 《Cephalalgia : an international journal of headache》1997,17(6):625-630
Co-existence of facial and occipital pain may occur in occipital neuralgia, migraine and cluster headache; suggesting convergence of trigeminal and cervical afferents. Such convergence has been shown in humans and other animals, but the site and extent of this are uncertain. In anaesthetized adult cats, the superior sagittal sinus and occipital nerve were stimulated electrically, and extracellular recordings made in the dorsolateral area of the upper cervical cord using glass-coated tungsten electrodes. Of 49 units in 10 cats, 33 (67%) had input from the superior sagittal sinus and the occipital nerve. Thirteen (27%) had superior sagittal sinus input and 3 (6%) had occipital nerve input. Convergent receptive fields were identified mechanically in 7 units. These experiments in cats show convergent input from occipital nerve and superior sagittal sinus on dorsolateral area units in two-thirds of cases studied. This experimental site of trigeminocervical convergence may relate to referral of pain in occipital neuralgia and other headaches. 相似文献
97.
C. L. G. Ham J. M. L. Engels G. T. van de Wiel A. Machielsen 《Journal of magnetic resonance imaging : JMRI》1997,7(5):933-937
The application of high gradient amplitudes and switching rates for MRI and spectroscopy, resulting in short rise times for the gradient field and high changes of the magnetic flux density in the patient, is known to possibly evoke peripheral nerve stimulation (PNS) in patients. These effects have been studied on 20 volunteers under different experimental circumstances. The results of these measurements are partially in line with earlier findings reported in the literature. New information is found for the dependence of the PNS threshold level as a function of the rise time of the gradient waveform. The PNS threshold level, expressed in terms of dB/dt, is found to be proportional with t?05, where t is the switch time for the gradients. Indications are found that |B|, the modulus of the gradient vector field, is more closely related to the PNS threshold level than Bz, the imaging component of the gradient field. From the experiments, it is furthermore concluded that only for the imaging protocols characterized by the application of long bipolar repetitive gradient pulse trains, such as echo-planar imaging, PNS is expected at the reported threshold levels. For the protocols based on spin echo, turbo spin echo, inversion recovery, fast field echo, etc., characterized by shorter gradient pulse trains, the threshold levels are expected to be much higher. 相似文献
98.
U. Irlenbusch 《Der Unfallchirurg》1997,100(8):675-677
Summary
Two patients with complete paralysis of the axillary nerve are reported on. One case is well documented. In both cases there
was very good functional adaptation, resulting from hypertrophy of the rotator cuff so that there was only a slight or no
loss of movement. The rotator cuff should therefore be exercised at an early stage when there is isolated axillary nerve damage.
The function of the supraspinous muscle is also discussed.
相似文献
99.
An atypical variant of reflex sympathetic dystrophy (RSD) is presented in a 45 year old female with a vascular malformation
of the right arm and chest wall. The mechanism was thought to be compression of the brachial plexus by the malformation. The
unique scintigraphic features of this presentation of RSD in the ulnar arterial distribution are illustrated. 相似文献
100.