摘要:

AbstractA total of 286 blastocysts were recovered 6 to 8 dayspost coitum (p.c.)from untreated or ovariectomized rabbits. The weight of the blastocyst and the volume of the blastocoelic fluid increased at a linear rate from seven to seven and one‐half daysp.c., thereafter they increased more rapidly. The weight of the embryonic tissue did not change appreciably between seven and eight daysp.c.The appearance of protein in the fluid was dependent on the stage of development, albumin being first detectable at six daysp.c.Seven days p.c., β‐globulin was detectable, followed by α‐ and γ‐globulins (seven and one‐quarter daysp.c.) and fibrinogen (seven and one‐half daysp.c.). Seven and one‐half daysp.c., the electrophoretic distribution of proteins was qualitatively similar to that of the maternal serum and peritoneal fluid, however, quantitatively different. Ovariectomy at six daysp.c.had no effect 24 hours later on blastocyst growth or blastocoelic fluid volume. In contrast, ovariectomy at six and one‐half daysp.c.had a negative effect 24 hours later on blastocyst growth, blastocoelic fluid enhancement and albumin accumulation in the fluid. These latter three phenomena were alleviated by administrati

ISSN:0003-276X    

DOI:10.1002/ar.1091580202

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

年代:1967

数据来源: WILEY

摘要:

AbstractRat blood platelets have two membrane systems in their cytoplasm. One, named the surface connected system (SCS), consists of vacuoles and large cavities which are in continuity with the plasma membrane. The inner surfaces of the membranes of this system have, in common with the plasma membrane, a thin coat of an amorphous substance which probably consists of acid mucopolysaccharides.The other system, named the dense tubular system (DTS), consists of slender membrane‐bound tubules which contain a homogeneous, rather electron dense substance. The DTS is not continuous with the plasma membrane or the SCS.Rat blood platelets incorporate various foreign substancesin vivoandin vitro; these substances are first adsorbed to the amorphous cell coat and subsequently taken into the SCS.It is suggested that the uptake of material by rat blood platelets reflects a membrane flow from the surface membrane to the SCS, and that the process is not phagocytic in nature since segregation and digestion of the incorporated material do not seem to take plac

ISSN:0003-276X    

DOI:10.1002/ar.1091580203

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

年代:1967

数据来源: WILEY

摘要:

AbstractThe histochemical localization of histidine in the epidermis and its relationship to skin histidase activity was described in rats varying in age from 17 days post‐coitum to 240 days post partum. In the fetal rat, the earliest histidase activity developed coincidentally with the first appearance of stainable histidine in the keratohyalin granules. In the neonatal period, histidase activity increased rapidly to several times the normal adult levels, corresponding in time to a period when the epidermal histidine‐containing zone was especially thick. As the thickness of this zone varied in subsequent periods during the life of the rat, parallel changes were observed in epidermal histidase activity suggesting the existence of a close interrelationship of histidine and histidase at the site of epidermal keratinization during the maturation of normal s

ISSN:0003-276X    

DOI:10.1002/ar.1091580204

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

年代:1967

数据来源: WILEY

摘要:

AbstractSites of aminopeptidase activity in the thymus of the mouse were compared in material incubated in L‐leucyl‐beta‐naphthylamide and in L‐leucyl‐4‐methoxy‐beta‐naphthylamide hydrochlorides as substrates. Sites of activity were most clearly demonstrated in frozen sections, postfixed in cold acetone, incubated in L‐leucyl‐4‐methoxy‐beta‐naphthylamide hydrochloride with Naphthanil Diazo Blue B and mounted in glycerogel.In thymuses of young mice, septa, medullary arteries and arterial capillaries were most strongly stained. Cortical lymphocytes and most medullary lymphocytes lacked aminopeptidase activity. In older mice, the high reactivity of the medulla contrasted sharply with the mostly unreactive cortex. In the medulla, the walls of the blood vessels, mesenchymal reticular cells and lymphocytes in the region of blood vessels were reactive. In the cortex, capsule, septa, and arterial capillaries were reactive; mesenchymal reticular cells, weakly so, and lymphocytes, unreactive. It would appear that much of the activity demonstrated by biochemical methods applied to thymic homogenates is a measure of reactive blood vessels and medullae. The general reaction of the medulla and the presence there of scattered, highly reactive cells lends added weight to the conclusion that the metabolic activities within the medulla are not

ISSN:0003-276X    

DOI:10.1002/ar.1091580205

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

年代:1967

数据来源: WILEY

摘要:

AbstractOn the dorsum of the slow loris tongue there are three vallate papillae, arranged in an inverted V‐shape. They contain abundant plexiform nerves and isolated nerve cells but have many taste buds only in its sides, closely associated with the subgemmal nerve plexus. Some ducts of serous glands locating deeply in this region directly open on the upper surface passing through the papilla. No foliate papillae are observed in the posterolateral region of the tongue, but instead of them is found a papilla of fungiform type, which wholly contains abundant plexiform nerves and has a furrow without serous gland ducts and taste buds. Furthermore, its summit is at the same level as the surface and same as its base in diameter, and has embryonic taste buds. From these neurohistologic characteristics this papilla should be regarded as an interformed papilla between the foliate and the ordinary fungiform papillae. Tongue lyssa consisting of hyalin cartilage and striated muscles innervated with motor end plate and simple sensory nerves seems to play a role as receptive organ of the tongue. Underneath the tongue is found well‐developed sublingua, which consists of hyalin cartilaginous skeleton and mucosa but has no taste buds. From segmental arrangement of neurovascular spaces in the skeleton it may be an ancestral structure of the ton

ISSN:0003-276X    

DOI:10.1002/ar.1091580206

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

年代:1967

数据来源: WILEY

摘要:

AbstractExtraocular muscles of the rat possess numerous nerves suitable for the study of fine structure. In these muscles, small nerves made up of one to ten myelinated and unmyelinated nerve fibers are surrounded by two or three layers of perineurium. The perineurium is arranged in concentric sleeves, each one cell thick. Continuous boundary membranes separate the perineural sleeves from the epineural and endoneural tissue space, but the boundary membranes may be spotty or absent between individual sleeves. The presence of boundary membranes around perineural cells distinguishes them from nearby fibroblasts which lack similar membranous investment. Tight intercellular junctions join the cells comprising each sleeve so that the nerves are completely ensheathed in perineurium. The number of sleeves decreases as the nerve becomes smaller, either by the termination of the innermost sleeve or by the loss of a sleeve as the nerve branches. The last sleeve ends shortly before the termination of the nerve. The perineurium is thus open‐ended peripherally and, at these places, the epineurium and endoneurium are continuous. Continuities between the epineurium and endoneurium also exist at the entrance and exit of blood vessels supplying the nerve and at points where reticular fibers pierce the perineurium. These structural features correlate well with the action of the perineurium as a diffusion barrier and as a pathway in the transmission of infection

ISSN:0003-276X    

DOI:10.1002/ar.1091580207

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

年代:1967

数据来源: WILEY

摘要:

AbstractThis study is based upon a dissection of 167 pelvic halves of Caucasian bodies. The distribution of the four major types, as based upon the Adachi classification, corresponds closely to that of the Western populations. The composite group has a distribution almost identical with the Japanese population studied by Adachi. No instances of the rare Type V were encountered. One unusual specimen which we have designated as Type VI is described.

ISSN:0003-276X    

DOI:10.1002/ar.1091580208

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

年代:1967

数据来源: WILEY

摘要:

AbstractTritiated thymidine was injected into pregnant BALB/c mice intravenously at 8, 10, 12, 14 and 16 days of pregnancy. Radioautographs were prepared in order to determine the extent of synthesis of DNA in the extraembryonic membranes at the above stages of gestation. The extent of synthesis of DNA was expressed as a radioactive index. The index is the per cent of labeled nuclei in a population of 1000 observed nuclei. Radioactive indices were determined for the nuclei of the endodermal cells of the visceral yolk sac and of the parietal yolk sac, for the nuclei of the trophoblastic cells of the junctional zone and of the labyrinth and for the nuclei of the trophoblastic giant cells. The observations show that in all of the examined types of cells the synthesis of DNA is extensive at days 10 and 12 of gestation and that it is nearly completed by day 14.

ISSN:0003-276X    

DOI:10.1002/ar.1091580209

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

年代:1967

数据来源: WILEY

摘要:

AbstractAttention is directed to an unusual type of junctional complex between Sertoli cells in the seminiferous epithelium. The space between the membranes of adjoining cells is narrowed to 70–90 Å over large areas of their contact surfaces. In the superficial cytoplasm of each cell is an extensive cisterna of the endoplasmic reticulum, parallel to the membrane and 400–600 Å from it. Spaced at more or less regular intervals in the thin layer of cytoplasm between the cisterna and the cell membrane are periodic densities that appear to be band‐like aggregations of fine filaments. The sub‐surface cisternae are smooth‐contoured on the side toward the cell membrane but bear ribosomes on the side facing the cytoplasm. The possible significance of these distinctive junctions is discussed in relation to the support of the germ cells and the coordination of the developmental events in the cycle of the seminiferous

ISSN:0003-276X    

DOI:10.1002/ar.1091580210

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

年代:1967

数据来源: WILEY

摘要:

AbstractYoung adult female rats were perfused with buffered aldehydes. Selected tissues were prepared for light microscopy by standard techniques. The only procedural modifications permitted were those required by the special physical and chemical characteristics of the tissue. Extreme brittleness called for special precautions in all manipulative steps from excision to final embedment. Turbulence during the early stages of dehydration was lessened by drop‐by‐drop addition of the next concentration of ethanol. High melting‐point paraffins and celloidin‐paraffin embedments were used to accommodate the hardness of the tissues and to prevent disarrangement during mounting. Steel knives specially sharpened with fine abrasives on plate glass were fitted with fluid reservoirs. Four micron sections were obtained routinely. Sections were transferred individually from the reservoir to glass slides. The common dyes used in light micoscopy tended to overstain these tissues. This tendency was overcome by using shorter exposure times, lower concentrations and blocking agents. The chromatic staining techniques familiar to histologists and pathologists were useful after minor modifi

ISSN:0003-276X    

DOI:10.1002/ar.1091580211

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

年代:1967

数据来源: WILEY