摘要:

AbstractGap junctions were observed in rat sublingual gland to link serous cells to serous cells, mucous cells to mucous cells, and myoepithelial cells to myoepithelial cells. In addition to connecting homologous cells, gap junctions were present between conterminous serous and mucous cells. Since the rat sublingual gland is innervated solely by parasympathetic nerves, the presence of gap junctions between disparate secretory cell types raises the possibility that serous and mucous cells in this organ secrete simultaneously in response to parasympathetic stimulation.

ISSN:0003-276X    

DOI:10.1002/ar.1092140112

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe ultrastructure of the hypothalamic intraventricular blood vessels is studied in two fish:Salmo gairdneri, a primitive teleost andGambusia affinis, a modern teleost. Morphological differences found between vessels belonging to the lateral and medial recesses inSalmoare described as well as contrasted with those ofGambusia.The endothelial cells are joined by elaborate tight junctions in both teleosts and also by desmosomes inGambusia.These vessels are continuous capillaries with pericytes which lack junctional complexes. The perivascular cells of the larger vessels display morphological characteristics of myoid cells.

ISSN:0003-276X    

DOI:10.1002/ar.1092140113

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

Abstract“Cholinergic” synapses of the bullfrog sympathetic ganglion cells were investigated with thin sectioning, complementary freeze‐fracturing, and deepetching methods after glutaraldehyde fixation. The protoplasmic (‐fracture) face (PF) of the postsynaptic membrane was characterized by intramembranous particles (IMPs), 3,500/μm2in density, consisting of larger particles, 10–12 nm in diameter, and smaller ones, 8–9 nm; the complementary exoplasmic (‐fracture) face (EF) contained larger and smaller IMPs, 750/μm2in density, and numbers of pits.By close inspection of the sections and freeze‐fracture replicas at high magnification and with deep‐etching in particular, it was concluded that aggregated IMPs might represent transmembranous components and that the particulate entities existing in the postsynaptic active zones might be larger in number than those exposed to view and counted here in the “cholinergic” synapses. An individual IMP often appeared to consist of five or six subunits arranged in a rosette with a central pit.These findings suggest that the aggregated IMPs, particularly the larger ones, may be closely related to the structure of the nicotinic ACh recep

ISSN:0003-276X    

DOI:10.1002/ar.1092140114

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractA case of unilateral absence of the radial artery is reported. The arterial system of the specimen was developmentally primitive with the anterior interosseous artery the chief blood supply to the forearm and hand. A “superficial ulnar artery” of small caliber supplemented the supply of the hand. Three large branches of the anterior interosseous artery supplied the hand with the lateral terminal branch replacing the radial artery distal to the wrist. The superficial palmar arch was formed by an anastomosis of the media and lateral terminal branches of the anterior interosseous artery. No deep palmar arch was present, but three palmar metacarpal arteries arose from a perforating artery which branched from a large dorsal branch of the anterior interosseous artery. The median artery was of small caliber and could not be traced beyond the midforearm. Based on this specimen and a review of other forearm and hand arterial variations, it is postulated that the ulnar artery may developmentally precede the median art

ISSN:0003-276X    

DOI:10.1002/ar.1092140115

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractOsteoblastlike cell migration and accompanying proliferation on a growth surface precoated with fetal calf serum (FCS) was quantified using a modification of the chemotactic model of Alessandri et al. (1983) and autoradiography. Culture dishes were precoated with 1%, 10%, or 100% FCS and were overlaid with agar. Three‐millimeter‐diameter wells were cut and first‐passage osteoblastlike cells in serum‐free medium were seeded into the wells. At 12 and 48 hours, outward migration was quantified by measuring (1) the distance osteoblastlike cells had migrated peripheral to the well margin, and (2) the number of osteoblast‐like cells peripheral to the well margin. The data indicated that the migration of osteoblast‐like cells was related to time and FCS concentration. More cells migrated a further distance at 48 hours than at 12 hours. In addition, with greater FCS concentrations, osteoblastlike cell migration increased;3H‐thymidine pulse labelling showed no incorporation of label into osteoblastlike cells at 12 hours. However, pulse labelling after 48 hours demonstrated that a small number of nuclei peripheral to the well margin were labelled. The data suggest that proliferation contributes negligibly to the population of osteoblastlike cells peripheral to the well margin. The appearance of osteoblastlike cells peripheral to the well margin is due primarily

ISSN:0003-276X    

DOI:10.1002/ar.1092140116

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

ISSN:0003-276X    

DOI:10.1002/ar.1092140101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY