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921.
Shashi Shrivastav Yousuf Sharief John Day Charles F. Reich Robert A. Bonar 《In vitro cellular & developmental biology. Plant》1981,17(12):1117-1124
Summary A new cell line, SS78, was established from a primary renal cell carcinoma of a Caucasian male. The tissue was dispersed with
collagenase, and viable cells were separated by flotation on a Ficoll-Hypaque gradient. In culture, the SS78 cells retained
a distinct epithelial morphology, and no fibroblastlike cells were seen. The cultured cells were aneuploid with a modal chromosome
number of 80 and had several marker chromosomes. Inoculation of the cultured cells into athymic nude mice caused tumors at
the sites of inoculation.
This research was supported in part by Grants CA 15972 and CA 14930 from the National Cancer Institute through the National
Bladder Cancer Project and by the Medical Research Service of the Veterans Administration. 相似文献
922.
Roeland van Wijk Lydie Tichonicky Jaques Kruh 《In vitro cellular & developmental biology. Plant》1981,17(10):859-862
Summary Exposure of HTC cells to sodium butyrate caused inhibition of growth. The site of growth inhibition was studied by time-lapse
cinematography and [3H]thymidine incorporation studies. Evidence is presented that sodiunm butyrate affected the cell cycle at a specific point
immediately after mitosis. Inasmuch as it does not modify the interphase duration after its removal, butyrate may be used
for HTC synchronization.
This work was supported by l'Institut Nationale de la Santé et de la Recherche Médicale and la Centre Nationale de la Recherche
Scientifique (L. T. and J. K.). 相似文献
923.
Linda E. Malick Anna Tompa Charles Kuszynski Parviz Pour Robert Langenbach 《In vitro cellular & developmental biology. Plant》1981,17(11):947-955
Summary The maintenance of primary cultures of adult hamster pancreatic cells on layers of irradiated C3H/10T1/2 cells was studied.
Various types of pancreatic cells, acinar, islet and ductular cells could be identified in the cultures by light and electron
microscopy. Morphologically the various pancreatic cells retained many differentiated characteristics of their respective
in vivo cell types. Insulin production was maintained at near Day 1 levels for the 16 d in culture for which it was measured.
Colonies of epithelial cells continued to grow during a 20 d culture period. It is believed that this procedure for maintaining
functional and growing pancreas cells in culture may be a useful in vitro model for studying the initiation of pancreatic
carcinogenesis.
Supported by Grant R01 CA 20022 and Contract N01 CP33278 from the National Cancer Institute, National Institutes of Health,
Bethesda, Maryland. 相似文献
924.
Fine, almost single cell, suspensions were produced from both existing suspension cultures containing large cell clumps and
from chopped callus pieces by immobilizing the cells in 4–5 mm diameter calcium alginate beads. The immobilized cells continued
to divide inside the beads and at the bead surface, and after 2–3 weeks' culture, fine cell suspensions were formed as a result
of loss of the surface cells into the medium. After removal of the cell suspensions by filtration, subsequent culture of the
beads in fresh medium resulted in the further production of homogeneous cell suspensions after 1–2 weeks. In this way an almost
continuous supply of fine cell suspensions could be obtained from cultures containing large clumps of cells. The cells produced
by this method remained in this state for at least one culture period, although in some instances repeated subculture resulted
in an increase in the size of cell groups. The technique has been successfully applied to the production of fine cell suspensions
ofCatharanthus roseus, Nicotiana tabacum andDaucus carota. 相似文献
925.
Mark J. Ottenbreit Susumu Inoue Ward D. Peterson James C. Lin 《Bioelectromagnetics》1981,2(3):203-215
Human marrow cells were irradiated with 2450-MHz CW microwaves in a fluid-filled waveguide irradiation system. Cell exposure was conducted by placing a marrow cell suspension in 20-μl glass microcapillary tubes that were positioned in the exposure chamber, and irradiated at power densities from 31 to 1,000 mW/cm2 (with corresponding specific absorption rates of 62 to 2,000 mW/g) for 15 minutes. The temperature of the sample was maintained at a fixed point. Sham-irradiated (SI) and microwave-irradiated (MWI) cells were cultured in a methylcellulose culture system for neutrophil colony proliferation. There was no reduction in neutrophil colony number on days 6–7 or 12–14 in cells exposed at 31 or 62 mW/cm2, but as the power density was increased to 1,000 mW/cm2, there was a reduction in colony number of MWI cells compared with SI cells. The microwave interaction with the human neutrophil colony-forming cells was apparently not related to temperature rise, or to the state of cell cycle, and was irreversible. 相似文献
926.
Prof. Dr. Dr. Karl-Heinz Wrobel Fred Sinowatz Roswitha Mademann 《Cell and tissue research》1981,217(2):289-310
Summary The intertubular stroma of the bovine testis is composed of narrow strands between two adjacent tubules and larger tri- and quadrangular interstices between three to four tubules. The latter contain the majority of Leydig cells, larger blood vessels and testicular lymph vessels. Ley dig cells occur in groups or cords, not every cell being in close contact to a capillary, lymph vessel or venule. Between adjacent Leydig cells intercellular canaliculi and gap junctions are frequently encountered. Bovine Leydig cells are further characterized by an abundance of ribosome-associated endoplasmic reticulum, by mitochondria often containing crystalloid structures and displaying both tubular and lamelliform cristae, as well as by a relative paucity of lipid droplets and lysosomes. Independent of the size of intertubular lymph vessels their walls consist only of an endothelium of varying thickness, no typical basal lamina or associated musculature being present. The interstitial surface of the endothelium sends anchoring cytoplasmic pedicles into the subjacent ground substance and collagen fibrils. Among occasional plasma cells, mast cells and mononuclear leucocytes, a regular constituent of the intertubular region studied is a population of electron-lucid, irregularly shaped cells (light intercalated cells = LIC) with slender, pleomorphic processes. These cells are believed to be involved in testicular androgen storage and distribution.Supported by a grant from the Deutsche Forschungsgemeinschaft 相似文献
927.
D. K. J. Ekström von Lubitz 《Cell and tissue research》1981,215(3):651-665
Summary The ultrastructure of the lateral-line neuromasts in the ratfish, Chimaera monstrosa is described. The neuromasts rest at the bottom of open grooves and consist of sensory, supporting, basal and mantle cells. Each sensory cell is equipped with sensory hairs consisting of a single kinocilium and several stereocilia. There are several types of sensory hair arrangement, and cells with a particular arrangement form patches within the neuromast. There are two types of afferent synapse. The most common afferent synapse has a presynaptic body and is typically associated with an extensive system of anastomosing tubules on the presynaptic side. When the tubules are absent, vesicles surround the presynaptic body. These synapses are often associated into synaptic fields, containing up to 35 synaptic sites. The second type of afferent synapse does not have a presynaptic body and is not associated with the tubular system. The afferent synapses of the second type do not form synaptic fields and are uncommon. The efferent synapses are either associated with a postsynaptic sac or more commonly with a strongly osmiophilic postsynaptic membrane. The accessory cells are similar to those in the acoustico-lateralis organs of other aquatic vertebrates. A possibility of movement of the presynaptic bodies and of involvement of the tubular system in the turnover of the transmitter is discussed. A comparison of the hair tuft types in the neuromasts of Ch. monstrosa with those in the labyrinth of the goldfish and of the frog is attempted. 相似文献
928.
Summary In the rostral hypothalamus of the domestic fowl, the magnocellular neurosecretory nuclei show a peculiar differentiation. Golgi studies of the supraoptic and paraventricular nuclei of the fowl reveal at least two major cell types: 1) large multipolar neurons, and 2) small interneurons. Golgi impregnations provide a detailed cytoarchitectural picture of the large-sized cells; the latter may well correspond to the neurosecretory cells demonstrated in the same regions by selective staining, and immunocytochemical and electron microscopical techniques.Electron microscopically, neuronal perikarya are observed to contain variable amounts of neurosecretory granules (100–200 nm in diameter; mean diameter of 160 nm) scattered throughout the cytoplasm. The diameters of these granules do not differ statistically in the two principal nuclear areas examined. The perikarya of these neurons display only a few axosomatic synapses containing electron-lucent and dense-cored vesicles (70–90 nm in diameter). Numerous nerve terminals of this type also end on the dendritic ramifications in the surrounding neuropil. 相似文献
929.
Dr. Jacques Bitsch 《Cell and tissue research》1981,220(1):99-113
Summary The wall of the receptaculum seminis of Thermobia domestica is composed of numerous glandular units, each with four enveloping cells (denoted 1 to 4) separated by ordinary epithelial cells and associated with a cuticular apparatus. During the moulting periods, which continue to occur in the adult stage, these cells undergo a series of transformations. Just before apolysis there is a dedifferentiation of numerous cytoplasmic organelles, but no mitosis has been observed. When the intima lifts off, the apical system of each glandular unit, i.e. the distal parts of the C2 and C3 cells surrounding the end apparatus, is also eliminated. Then at the apex of each glandular unit, a new ductule is formed in the cavity of which a long ciliary process grows up from cell C1. Finally comes the phase of cuticle formation, i.e., epicuticle for the ductules, epi-and endocuticle for the intima lining the central cavity of the receptaculum. Various cell types participate in secretion of cuticle, the ciliary cells (C1) being responsible for the formation of the porous end apparatus. At ecdysis almost all of the new intima has been secreted and the apical systems are once more differentiated. These transformations are compared with those recently described in other exocrine glands of arthropods, e.g., tegumentary glands and accessory glands of the genital ducts. 相似文献
930.
Summary The fine structure of follicular cells of the adenohypophysis was examined in fetal, neonatal, and adult beagle dogs. Prior to birth, undifferentiated follicular cells are common. At birth mature cells that form follicles are routinely encountered. The fine structural appearance of follicular cells is unchanged between birth and adulthood. Follicular cells of puppies and adults are, however, distinguished by the presence of unusual complexes within distended cisternae of the rough endoplasmic reticulum. These complexes vary greatly in morphology, some appear as a maze of interconnecting tubules while others show a highly organized paracrystalline configuration. The presence of these paracrystalloid structures in follicular cells supports the view that they represent a distinct pituitary cell type.Supported by NIH Grants AM19743 and NS12969The authors wish to thank John Patrikes and Helen Mantulin for their expert technical assistance 相似文献