| 释义 |
‖ ramus|ˈreɪməs|
Pl. rami |ˈreɪmaɪ|.
[L. rāmus branch, etc.]
1. Anat.
a. A process of a bone, esp. of the ischium and pubes, and of the jaw-bone.
1803Med. Jrnl. IX. 394 The transverse space existing between the rami of the ischium. 1843J. G. Wilkinson Swedenborg's Anim. Kingd. I. i. 22 Between the ramus of the lower jaw, and the base of the tongue. 1855Ramsbotham Obstetr. Med. 5 The ischium is connected..with the pubis at the junction of the rami.
b. A major branch of a nerve; ramus communicans (pl. rami communicantes), a branch of one nerve that joins another; esp. one of those joining a sympathetic ganglion with a spinal nerve.
1811J. Bell Anat. Human Body (ed. 3) II. 515 Whilst it [sc. the tibial nerve] is yet in the hollow behind the joint formed by the hamstring tendons, it gives off a nerve which comes out from the ham, and descends superficially on the back of the leg. This has been called ramus communicans tibialis. Ibid. 517 When it [sc. the fibular nerve] arrives at the anular ligament, it is much diminished. Here it divides into the ramus dorsalis pedis profundus, and superficialis. 1893H. St. J. Brooks in H. Morris Treat. Human Anat. v. 864 Each of the thoracic ganglia is connected to the corresponding spinal nerve by two rami communicantes, a white and a grey. The white ramus communicans consists of medullated fibres... The grey ramus communicans or revehent nerve is formed of non-medullated fibres. Ibid. 865 Occasionally the number of rami is increased to five or six. 1927W. Keiller Nerve Tracts i. 147 The spinal nerves distal to the root ganglia divide almost immediately into anterior and posterior rami. 1946Gray's Anat. (ed. 29) 1078 The sensory root [of the ciliary ganglion] is formed by a ramus communicans from the nasociliary nerve. 1964A. J. Berger Elem. Human Anat. v. 84 The definitive spinal nerve is very short because it splits into two main branches (or rami) almost as soon as it is formed. The smaller dorsal primary ramus innervates the deep back muscles. 1967G. M. Wyburn et al. Conc. Anat. iii. 93/1 Incise one or two intercostal spaces to expose the intercostal nerves and find their slender connections with the sympathetic trunk, i.e. the grey and white rami communicantes. 1972C. R. & T. S. Leeson Human Structure iii. 11/1 Immediately after emerging from an intervertebral foramen, the spinal nerve divides into a posterior primary ramus and an anterior primary ramus.
2. Ornith. = barb n. 6.
1882H. Gadow in Proc. Zool. Soc. 411 The series of radii or barbules on either side of the rami or barbs.
3. Zool. In the mastax of rotifers, each of the two articulated parts of the incus that are attached to the fulcrum.
1856Phil. Trans. R. Soc. CXLVI. 426 The incus..consists of distinct articulated portions. The principal are two stout rami..resting on what appears to be a slender pedicel (fulcrum, h). 1886, etc. [see fulcrum 2 c]. 1972M. S. Gardiner Biol. Invertebrates vii. 236/2 The wall [of the mastax]..is extended into seven firm, sclerotized pieces, the trophi, moved by small individual muscles. These pieces are a single median fulcrum and three pairs of lateral ones, two rami, two unci, and two manubria. |