摘要:

AbstractMicroscopical observations have been made on the blood circulation of intact, unanaesthetized specimens of the transparent glass catfish. Along the segmental arteries of the trunk, groups of short, curled vessels of capillary dimensions (termed inter‐arterial anastomoses) branch off and reunite to form large so‐called secondary arteries running parallel to the main (primary) arteries. Secondary arteries give rise to capillaries in the median ventral fin membrane. Secondary capilaries are drained via separate secondary veins. When blood passes from primary to secondary arteries via the inter‐arterial anastomoses a pronounced plasma skimming is observed. Hence, blood perfusing the secondary capillaries of the fin membrane contains very few red blood

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1986.tb00863.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe wheel organ is a specialized epithelium in the roof and sides of the adult lancelet oral cavity. It borders the oral epithelium proper, separated by a thin strip of margin cells which are not ciliated but contain a few large dense‐cored vesicles apically. The wheel organ cells are tall and strongly ciliated and have dark, heterochromatin‐rich nuclei. Dorsally, and slightly paramedially, the organ is further specialized, forming the so‐called Hatschek's groove (pit), which consists of two ciliated cell types. The first type synthesizes a dense granular material, the granules being approximately 95 nm in diameter. This is stored basally and apparently it is also released through the basal cell membrane into the blood cavities. The cells at the bottom of Hatschek's groove have peculiar rod‐shaped apical cellular regions. Each cell bears one tall cilium surrounded by microvilli and it is apparently involved in the production of secretory material into the groove. It is evident that the histology, and probably also the function, of the wheel organ and its groove is much more complex than hitherto b

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1986.tb00864.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe peritreme of the adult female miteVarroa jacobsoniis located laterally above coxa III and is enclosed within a peritrematal shield which has a slit at the end. The peritrematal shield is cuticular in nature. The peritreme is lined with a thick inner membrane which has numerous tooth‐like projections. The outer membrane of the peritreme is thin and smooth. In between these two membranes is a layer of columnar cells. The internal structure of the peritreme in relation to the female mite's ability to adjust to different atmospheric conditions is discusse

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1986.tb00865.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractIn vitrophagocytosis by peripheral blood leucocytes of the dogfishScyliorhinus caniculaL. was examined by exposing adherent cells to a variety of particulate and soluble antigens and inert material. Their subsequent uptake was monitored by light, scanning and transmission electron microscopy. The monocyte and the neutrophil‐like granulocyte were found to be the major phagocytic cells. Larger particles like yeasts and erythrocytes were the most avidly phagocytosed. From studies on the effects of pH, temperature and the presence of plasma, metabolic inhibitors and divalent ions, it appeared that optimum phagocytosis occurred at pH 7.0 and between 10 and 20°C. Serum factors did not enhance the process in this species. Finally, thein vitroclearance of 5 bacterial species indicated that the presence of blood phagocytes had little or no effect on bacterial numbe

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1986.tb00866.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractIn vivophagocytosis by peripheral blood leucocytes of the dogfishScyliorhinus caniculaL. was examined by monitoring the fate of a variety of injected materials, both particulate and soluble, in normal and immunised fish. Carbon, yeasts and bacteria were phagocytosed by monocytes, thrombocytes and type 1 granulocytes (neutrophils). Quantitativein vivoantigen clearance studies employed five species of bacteria, yeast and KLH. After an initial significant decrease of these antigens in the circulation, low numbers of viable bacteria and yeasts and low concentrations of KLH persisted for long periods after injection. Previous exposure to several of these antigens had little or no effect.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1986.tb00867.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe ventral sense organ, below the mouth, is composed of 30 primary sensory cells situated in a row perpendicular to the long axis of the animal. Each cell carries one long and slender, modified cilium which arises from an apical pocket in the cell. The sensory cells project 15 axons at each side of the pharynx to the brain, which is rostrally paired and terminates in bulb‐like swellings. Each of these bulbs contains four cell bodies, which, according to their fine structure, as well as the synaptic connections with receptor and brain fibers, belong to three different types. It is suggested that the sense organ is a chemosensor and that its remarkable similarity to the vertebrate mechanisms for olfaction makes it probable that the appendicularianOikopleura dioicapossesses a ‘protochordate’ counterpart to the craniate olfactory appa

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1986.tb00868.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe vascular patterns of the epidermally derived slime glands of the Atlantic hagfish,Myxine glutinosa, and of the Pacific hagfish,Eptatretus stouti, have been studied by scanning electron microscopy of vascular corrosion casts. InMyxinea simple two‐dimensional vascular network sheaths the slime glands, while inEptatretusthere is also a great number of capillary loops of different lengths arising from the sheathing network and extending into the interior of the glands. These basic differences in slime glands vascular patterns are thought to reflect substantially different physiological behaviour of the slime glands inMyxineandEptatretu

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1986.tb00869.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractFactors affecting the fecundity ofPhysasp. were studied in the laboratory. Aging of the culture medium resulted in a significant decline in oviposition of this snail species. Changes in ionic levels of the rearing water did not seem to affect egg laying under the experimental conditions. Conspecific snail‐conditioned water and faecal homogenates to some extent effectively inhibited oviposition, but spinach infusion had no such effect. The results are consistent with the suggestion that some sort of oviposition inhibitor(s) is released by the snails in the culture water. The inhibitor compound(s) is denatured on boiling or after incubation with a proteas

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1986.tb00870.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY