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91.
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
92.
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
93.
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
94.
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
95.
96.
Optic nerve injury demonstrated by MRI with STIR sequences 总被引:1,自引:0,他引:1
S. Takehara T. Tanaka K. Uemura Y. Shinohara T. Yamamoto T. Tokuyama A. Satoh 《Neuroradiology》1994,36(7):512-514
We studied nine patients with optic nerve injury associated with closed head trauma by magnetic resonance imaging (MRI) with short inversion time inversion recovery (STIR) sequences on 11 occasions from 4 days to 14 years after the injury: three studies were within 17 days and eight over 4 months to 14 years. MRI revealed abnormal high signal in 10 of the 11 injured nerves. MRI 4 days after the injury showed no abnormality. 相似文献
97.
用手术显微镜对50例成人的颈阔肌作了观察和测量。将每侧颈部分为9个区,颈阔肌位于前6区。肌的内侧界约相当于颏舌骨连线中点稍下到锁骨胸骨端稍外侧处的连线,左右侧肌夹有40°角;外侧界为下颌角稍后到锁骨肩峰端内侧3cm处的连线;下界在第一肋间隙平面,有的肌下份出现一些较宽的裂隙;上界在下颌骨体,并与某些表情肌相连续。肌的面积约150cm~2,锁骨上部约占120cm~2。后份肌纤维略呈S形弯曲。肌与深层结构联系较松。本文还对面神经和颈丛与颈阔肌有关的分支,进行了观察。对和颈面部临床应用等有关的问题进行了讨论。 相似文献
98.
The afferent nervous supply to the thymus gland has been investigated by means of the retrograde transport of horseradish peroxidase. It has been shown that the thymus receives an afferent supply from the nodose ganglia of the vagus and from the dorsal root ganglia C1–C7. The afferent innervation of the right and left thymic lobes is bilaterally organized; the fibers of a small celled population of nodose ganglion neurons cross outside the thymus and those of a larger celled population cross within the thymus gland. The functional implications of these findings are discussed in the context of central nervous system-immune system interactions. 相似文献
99.
100.