Functional and developmental morphology最新文献

The neural network in the tongue of Gallus domesticus was visualized using a cholinesterase technique. The network of acetylcholinesterase positive nerve fibres was formed by the tortuous myelinated as well as non-myelinated, preganglionic and postganglionic nerve fibres. The network was closely associated with a chain of acetylcholinesterase positive ganglia, the nerve fibres of the fungiform, filiform, circumvallate and foliate papillae and with the fibres of the neural terminal network.

The authors studied the regional localization of two dehydrogenases--glycerol-3-phosphate dehydrogenase and succinate dehydrogenase--in the telencephalic nuclei and fibre tracts of Barilius bendelisis by histoenzymological methods. The activity of these dehydrogenases varied from moderately positive to strongly positive in the nuclear areas and from intensely to strongly positive in the fibre tracts, except those related to the olfactory tubercle. G3PD appears to play an important role in the biosyntheses of phospholipids and to form a link between glycolysis and the pathway of the hexose-monophosphate shunt, in addition to its usual role in the degradation of glucose, along with other dehydrogenases, including succinate dehydrogenase.

The authors studied the origin and variability of the tributaries of the v. portae in 30 adult laboratory mice (Mus musculus var. alba) of both sexes, after first injecting the portal bed with bluedyed latex. In 19 cases (63.3%) the v. portae was formed by the union of three tributaries and in 11 cases (36.7%) by the union of four to eight. The v. mesenterica cranialis was a constant tributary in every case (100%). The v. lieanalis was a tributary in 27 cases (90.0%) and the next most frequent tributary was the v. pancreaticoduodenalis (14 cases--46.7%) A v. gastrica sinistra was found in every case (100.0%), in 24 cases (80.0%) it joined the v. lienalis and in the other six (20.0%) it was a direct tributary of the v. portae. A v. cardiaca was also observed in every case (100%). In 28 cases (93.3%) it was a tributary of the v. gastrica sinistra and in the remaining two (6.7%) it was a direct tributary of the v. portae. A v. pylorica was found in 27 mice (90.0%). Most often it was a tributary of the v. gastroepiploica dextra (11 cases--36.7%) or the v. gastrica sinistra (9 cases--30.0%). In only one case was it a direct tributary of the v. portae. A v. pancreaticoduodenalis cranialis was present in a total of 28 cases (93.3%). In 12 cases (40.0%) of already originated in the region of the cauda pancreatis and in 16 cases (53.3%) it arose only from the corpus and caput pancreatis.(ABSTRACT TRUNCATED AT 250 WORDS)

The ultrastructure of synapses in human brain which died with ischemic heart disease in various time after ischemic injury showed that the whole range of symptoms of compensatory character appears together with degenerative changes. The most important changes of presynaptic membrane consist of pinocytous invagination. Tubular structures in region of synaptic contact as well as on the surface of small invaginal axonal branches, dendrites and small spines are also found. We assume that plastic rebuilding of synapses have compensatory significance.

The investigation was undertaken to investigate the formation and association of neural network and their fibres with nerve cells and ganglia in the parenchyma. The staining of the neural network was done by the cholinesterase technique under the maintained pH 5.2, temperature 40 degrees C and incubation period 30 hrs. The neural network was formed by a good number of tortuous thick nerves and was related either with nerve cells or ganglia. At times, it was formed by a good number of thick nerves and a few thin nerves in the connective tissue space.

This study reports the mechanism of involvement of vitamin C in the pathogenesis of induced oral carcinogenesis in the hamster cheek pouch epithelium. This site was exposed to either DMBA singly or in combination with vitamin C or DMBA for 7 weeks followed by only vitamin C till tumour induction. Macroscopically, vitamin C reduces the epithelial tumour incidence in the hamster cheek pouch. Microscopically tumours induced by DMBA alone were well differentiated squamous carcinomas in all the animals, whereas those induced by DMBA plus vitamin C were papillary epidermoid carcinomas with minimal invasion. These observations suggest that vitamin C is capable of restricting the growth of the initiated cells and does not allow the invasion of the subepithelium. The mechanism of action of vitamin C in the process of restricting growth and invagination was clearly shown in ultrastructural pathology too. In vitamin C exposed tumours the dermal epidermal junction of the cheek pouch epithelium maintains basement membrane integrity, with the presence of cellular organelles and cytoskeletal structure of the cells.

Exencephalic tail-short (Ts/+) embryos were obtained from mating normal mice of Patch strain with Ts/+ mice from Babl/c strain. The most common eye malformations in the exencephalic embryos were exophthalmy, microphthalmy, eye ball irregularity and corneal opacity. Squint eye and unilateral anophthalmy occurred at a lower frequency. The eye abnormalities were recognized histologically by 11-days of gestation. The retina was retarded in development. Lens fibres were swollen and some of them appeared degenerated. Lens epithelium was protruded anteriorly, detached from the underlying lens and joined the corneal endothelium. The lens remained in close contact to the ectodermal layer, forming a thick lens stalk. At the 16-day stage, the corneal epithelium became irregular in thickness and the corneal stroma was discontinuous, having disarranged collagenous fibrils. In a few embryos the corneal endothelium was absent. In the squint-eyed embryo, the cornea bulged through the opened eyelids, while in an anophthalmic embryo it was thick and underdeveloped. Generally, the upper and lower eyelids of the exencephalic embryos were asymmetrical, and the lower lid appeared covered by a thick irregular peridermal layer.