Abstract：
:The spermatogonial stem cell line in prepubertal and adult bovine testis was studied by electron microscopy and protein gene product 9.5 immunohistochemistry. Three successive spermatogonia precursor cell configurations were observed. Small basal stem cells were found to possess a spherical shape and nuclei with two to three nucleoli. They were observed in prepubertal testes (25 and 30 weeks) and in low numbers during all the stages of the seminiferous epithelial cycle in the adult. Aggregated spermatogonia precursor cells are the dominating germ cell type in the 25-week-old and 30-week-old calf. In the adult seminiferous epithelium, they cause expansion of the basal tubular compartment as they form dense groups containing up to 15 cells. These groups are observed concomitantly with cycling A-spermatogonia and preleptotenes at the beginning of spermatocytogenesis. At the end of A-spermatogonia propagation, the aggregated spermatogonia precursor cells separate and intermingle with cycling A-spermatogonia. The spermatogonia precursor cells can later be found together with I-spermatogonia as members of an interconnected cellular network of medium-sized cells. When the I-spermatogonia divide to form the smaller B-spermatogonia, the precursor cells, which stay connected with the cycling spermatogonial population, pass through a growth phase. They can now be considered as committed spermatogonia precursor cells and are continuously being transformed into A1-spermatogonia to start a new round of spermatocytogenesis. Ultrastructurally, all members of the precursor cell line are similar. However, a number of features have been found to show a quantitative increase (endoplasmic reticulum, mitochondria) or to exhibit a rising degree of complexity (nucleolus) during the progression from basal stem cells to committed spermatogonia precursor cells.
journal_name
Cell Tissue Resjournal_title
Cell and tissue researchauthors
Wrobel KH,Bickel D,Kujat R,Schimmel Mdoi
10.1007/BF00583394subject
Has Abstractpub_date
1995-08-01 00:00:00pages
249-59issue
2eissn
0302-766Xissn
1432-0878journal_volume
281pub_type
杂志文章abstract：:Rainbow trout (Oncorhynchus mykiss) were exposed to ion-poor (soft) water to test the hypothesis that naturally induced proliferation of branchial chloride cells causes a thickening of the blood-to-water diffusion barrier. This was achieved by using a combination of scanning and transmission electron-microscopic techn...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/s004410050622
更新日期：1996-07-01 00:00:00
abstract：:To determine whether lipid-secreting cells have cytosolic Ca2+ concentration ([Ca2+]c)-related secretory mechanisms, morphological changes and intracellular calcium dynamics of Harderian glands of guinea pigs stimulated by secretagogue were studied by electron microscopy and Fura-2/AM digital image analysis. Control g...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00327979
更新日期：1993-10-01 00:00:00
abstract：:Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with highly potent neurotrophic and neuroprotective effects. PACAP and its receptors occur in the retina and PACAP has been applied in animal models of metabolic retinal disorders to reduce structural and functional damage. Furthermore, PACAP...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/s00441-012-1349-0
更新日期：2012-04-01 00:00:00
abstract：:Pulmonary neuroepithelial bodies (NEBs) are extensively innervated organoid groups of neuroendocrine cells that lie in the epithelium of intrapulmonary airways. Our present understanding of the morphology of NEBs is comprehensive, but direct physiological studies have so far been challenging because the extremely diff...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/s00441-005-1111-y
更新日期：2005-07-01 00:00:00
abstract：:Glaucoma, a disease of the optic nerve and retina, causes blindness in millions of people worldwide. Currently available therapies for this disease only attempt to reduce intraocular pressure, the major risk factor, without addressing the associated optic neuropathy and retinopathy. Development of glaucoma neuroprotec...
journal_title：Cell and tissue research
pub_type： 杂志文章,评审
doi：10.1007/s00441-013-1584-z
更新日期：2013-08-01 00:00:00
abstract：:In previous studies the differentiation of the epithelium in the human hard palate has been described stereologically using parameters expressed per unit tissue volume. Since single epithelial cells represent the true biological units of this tissue, it became necessary to estimate the absolute size of such cells in o...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00216577
更新日期：1981-01-01 00:00:00
abstract：:The distribution of Mg++-ATPase in osteoclasts along the endosteal surface of the chick tibia was investigated by neutral and alkaline pH cytochemical methods at the electron-microscopic level. Reaction product was observed in mitochondria, cytoplasmic vesicles, and ruffled-border membrane. Levamisole, ouabain, and va...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00218550
更新日期：1986-01-01 00:00:00
abstract：:Thyroid hormone (TH) plays an important role in regulating ovarian development. However, the mechanism involved remains unclear. Evidence suggests that glucose is essential for ovarian development, and its uptake is mediated by several glucose transporter proteins (Glut). We have investigated the effects of TH on Glut...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/s00441-016-2453-3
更新日期：2016-11-01 00:00:00
abstract：:The spatial localisation of insulin-like growth-factor-binding protein-2 (IGFBP-2) and its mRNA was investigated during larval and post-larval developmental stages of the gilthead seabream ( Sparus aurata) by immunohistochemistry and in situ hybridisation with specific antisera and riboprobes. During larval developmen...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/s00441-004-0952-0
更新日期：2005-01-01 00:00:00
abstract：:The excretory system of Macrobiotus richtersi consists of one dorsal and two lateral components and shows a high degree of structural complexity. In each of these a tricellular external lobe and a column can be distinguished, the two parts being connected distally. The surface of the lobe cells is increased by deep ba...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00239339
更新日期：1980-01-01 00:00:00
abstract：:1. Early oocytes of Platynereis dumerilii are found in clusters floating in the coelom. The oocytes of a cluster form a syncytium which is enveloped by several sheath cells. 2. At stage 2, only a single sheath cell per cluster remains, and it penetrates the group of rounded oocytes, enveloping each one of them. At sta...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00222043
更新日期：1975-07-16 00:00:00
abstract：:The presence of immunoreactive enkephalin, dynorphin, vasoactive intestinal polypeptide, cholecystokinin, substance P and neuropeptide Y in nerve fibers that project to the guinea-pig inferior mesenteric ganglion was analysed, after different denervation and ligation procedures. A quantitative analysis demonstrates th...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00219741
更新日期：1988-09-01 00:00:00
abstract：:In the central nervous system of the male domestic flow, metenkephalin (ENK) immunoreactive perikarya and fiber tracts as well as extensive but sharply delimited fiber networks were visualized by means of the PAP technique. The most striking results were: (1) The demonstration of an association of ENK-containing struc...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00236920
更新日期：1980-01-01 00:00:00
abstract：:Developmental alterations of paranodal fiber segments have not been investigated systematically in human nerve fibers at the light- and electron-microscopic level. We have therefore analyzed developmental changes in the fine structure of the paranode in 43 human sural nerves during the axonal growth period up to 5 yea...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00333704
更新日期：1993-09-01 00:00:00
abstract：:Four different types of spermatogonia were identified in the seminiferous tubules of the Japanese quail: a dark type A (Ad), 2 pale A types (Ap1 and Ap2), and a type B. A model is proposed describing the process of spermatogonial development in the quail. The Ad spermatogonia are considered to be the stem cells. Each ...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00319382
更新日期：1992-03-01 00:00:00
abstract：:In the stalk-eyed fly Cyrtodiopsis whitei (Diopsidae; Diptera), the relatively long optic nerve develops within the tight lumen of a very short eyestalk. Axonal growth is generally considered in terms of path finding, selective fasciculation, and towing. Physical forces that are necessary for axon lengthening are gene...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/s00441-005-1142-4
更新日期：2005-09-01 00:00:00
abstract：:With the use of immunocytochemistry, it was shown that both the supraoptic and paraventricular hypothalamic nuclei in humans contain at least two different neurophysins. These two human neurophysins are immunologically related to bovine neurophysin I and neurophysin II, respectively. One human neurophysin is associate...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00240096
更新日期：1979-02-15 00:00:00
abstract：:Locust lipoproteins (lipophorins) were localized by indirect immunofluorescence- and immunogold labelling in cryosections of dorsolongitudinal flight muscles. Immunolabelling was performed with monoclonal antibodies against apolipoproteins epitopes that are exposed at the surfaces of the lipophorin particles. Both at ...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00216654
更新日期：1988-06-01 00:00:00
abstract：:Mlh1 is a member of DNA mismatch repair (MMR) machinery and is also essential for the stabilization of crossovers during the first meiotic division. Recently, we have shown that zebrafish mlh1 mutant males are completely infertile because of a block in metaphase I, whereas females are fertile but have aneuploid progen...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/s00441-007-0550-z
更新日期：2008-04-01 00:00:00
abstract：:Dental pulp stem cells (DPSCs) are an attractive alternative mesenchymal stem cell (MSC) source because of their isolation simplicity compared with the more invasive methods associated with harvesting other MSC sources. However, the isolation method to be favored for obtaining DPSC cultures remains under discussion. T...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/s00441-013-1630-x
更新日期：2013-07-01 00:00:00
abstract：:In the fish retina, connexon densities of gap junctions in the outer horizontal cells are modulated in response to different light or dark adaptation times and wavelengths. We have examined whether the connexon density is a suitable parameter of gap junction coupling under in situ conditions. Short-term light adaptati...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00318795
更新日期：1992-05-01 00:00:00
abstract：:The chemical nature of the thickened plasma membrane of cornified cells in stratified squamous epithelium was investigated in comparison with that in noncornified epithelium. Localizations of transglutaminase, molecular weight 92,000 daltons, and detection of epidermal cysteine proteinase inhibitor were effected with ...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00215516
更新日期：1987-08-01 00:00:00
abstract：:The three-dimensional architecture of the tubular endocytic apparatus and the endoplasmic reticulum in the rat yolk-sac endoderm was investigated after loading with horseradish peroxidase-conjugated concanavalin A by intrauterine administration. After 30 min, small vesicles (50-150 nm in diameter), small tubules (80-1...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00414178
更新日期：1994-11-01 00:00:00
abstract：:The posterior rhombencephalic tela choroidea of the bullfrog was examined by electron microscopy. This membrane, the pia-ependymal roof of the caudal hindbrain, contains a large central region characterized by cuboidal ependymal cells which surround sizable microscopic apertures -- the interependymal pores. Ultrastruc...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00220439
更新日期：1979-11-01 00:00:00
abstract：:Desmin is a muscle-specific type III intermediate filament essential for proper muscular structure and function. In human, mutations affecting desmin expression or promoting its aggregation lead to skeletal (desmin-related myopathies), or cardiac (desmin-related cardiomyopathy) phenotypes, or both. Patient muscles dis...
journal_title：Cell and tissue research
pub_type： 杂志文章,评审
doi：10.1007/s00441-014-2016-4
更新日期：2015-06-01 00:00:00
abstract：: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 d...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00236253
更新日期：1981-01-01 00:00:00
abstract：:1,25-Dihydroxyvitamin D3 and 24,25-dihydroxyvitamin D3 have antagonistic effects on the acellular bone of the tilapia Sarotherodon mossambicus. 1,25-Dihydroxyvitamin D3 inhibits the activity of the lining osteoblasts. Prolonged administration leads to demineralization of the bone matrix. Injection of 24,25-dihydroxyvi...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00206270
更新日期：1983-01-01 00:00:00
abstract：:In the intestine of the filtering zooids of B. schlosseri three segments can be distinguished. In the intermediate segment the epithelium, which is encrusted by the ampullae of the pyloric gland, shows marked aspects of alteration. In the proximal and distal segments, ciliated mucous, vacuolated and endocrine-like cel...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00219771
更新日期：1977-08-26 00:00:00
abstract：:Germ cells of human fetuses aged 7-13 weeks were studied. Dense fibrous material called nuage was found in the cytoplasm of human fetal germ cells. The nuage increased in frequency in the germ cells during the interval studied. In oogonia the nuage occurred much more frequently than in spermatogonia and the frequency ...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/BF00209243
更新日期：1978-11-09 00:00:00
abstract：:Light microscopy of native preparations, histology, and electron microscopy have revealed that Phlebotomus duboscqi belongs to a class of sand fly species with prompt development of the peritrophic matrix (PM). Secretion of electron-lucent fibrils, presumably chitin, starts immediately after the ingestion of a blood m...
journal_title：Cell and tissue research
pub_type： 杂志文章
doi：10.1007/s00441-009-0802-1
更新日期：2009-08-01 00:00:00
