The cervical sympathetic trunk--a new hypothesis.

There is a sympathetic ganglion, in relation to most if not all thoracic and lumbar segments whereas there are only 3 or 4 sympathetic ganglia in the cervical region. Thus it may be inferred that sympathetic ganglia are not directly related to spinal nerves. Therefore, the hypothesis is put forward that sympathetic ganglia are associated chiefly with intersegmental vessels such as the intercostal and lumbar arteries and that the differences seen in the neck region are due to the disappearance of most of the cervical intersegmental arteries and the subsequent modifications that follow during development. This results in the fusion of the upper 4 cervical ganglia to form the superior cervical sympathetic ganglion in relation to the developing external carotid artery which seems to provide the necessary inductive stimulus. Furthermore, the antero-inferior migration of the heart, its corresponding arch arteries and the dorsal aorta bring about the formation of the ansa subclavia around the subclavian artery and the positioning of the stellate ganglion behind the vertebral artery.

Vastus medialis oblique: an anatomic and physiologic study.

The lower part of the vastus medialis, which originates chiefly from the tendon of the adductor magnus, has been designated as the "vastus medialis oblique." This muscle is peculiar to man. The fibers of the muscle are mostly horizontal; therefore they are in a unique position to stabilize the patella against the femur in the later stages of extension of the knee. This article details the anatomic and physiologic features of the vastus medialis oblique.

The retroconchal space of the lateral nasal wall.

The retroconchal space is defined in this article as the posterior part of the lateral wall of the nasal fossa. Considerable variations in the size and shape of this retroconchal space exist, these in turn depending on the variations of the middle and inferior conchae. The retroconchal space can be defined in plain radiographs or in nasopharyngograms. This would be of help in pinpointing the site of a neoplasm.

Radiology of the Eustachian fossa.

The Eustachian fossa, when visualised in contrast radiography and cinefluorography, shows a wide variety of shapes and sizes. Moreover, the fossa also exhibits varying degrees of changes during swallowing. Brief accounts of the technique of contrast radiography and the appearance of the normal nasopharyngograms are given to facilitate the understanding of the radiological features of the fossa.

Mitochondrial variations in the spinal ganglion cells of the slow loris: an electron microscopic study.

The fine structure os spinal ganglia from seven slow lorises (Nycticebus coucang coucang) was studied following perfusion fixation using different concentrations of glutaraldehyde and post-fixation in 1% osmic acid. Two cell types, one light (63%), and the other dark (37%) were reported out of the total number of 425 neurons counted. Almost all the light cells contained filamentous mitochondria, whereas only 35% of the dark cells contained filamentous mitochondria, the other 65% having vacuolated mitochondria. The significance of this mitochondrial variation in the spinal ganglion cells of the slow loris is undecided.

Regeneration of nasopharyngeal epithelium in Macaca fascicularis.

Regeneration of the nasopharyngeal epithelium in Macaca fascicularis occurs as a result of migration of epithelial cells from the margins of the lesions as well as from the neighbouring glandular ducts and epithelial crypts. The study further reveals that the basal cells are the progenitors of both goblet and ciliated cells. The regenerating epithelium at first consists of mucus-containing cells which are finally converted into normal globlet and ciliated cells. The formation of centrioles and concurrent reduction in the amount of 'mucus' droplets, and rearrangement of centrioles towards the luminal surface of the cells along with simultaneous development of cilia in some of these mucus-containing cells are stages in the differentiation of ciliated cells. However, some cells which do not possess secretory droplets may also develop into ciliated cells directly.