The early development and implantation of the golden hamster, Cricetus auratus, and the associated endometrial changes

1948 ◽  
Vol 82 (2) ◽  
pp. 231-275 ◽  
Author(s):  
Margaret C. Ward
Development ◽  
1968 ◽  
Vol 19 (3) ◽  
pp. 341-345
Author(s):  
M. P. Young ◽  
J. T. Whicher ◽  
D. M. Potts

Previous work on the early development of the golden hamster includes the investigation of Ochs (1908), Graves (1945) and Ward (1948), all at the level of the light microscope. Austin (1963) has examined the ultrastructure of the oocytes of the golden hamster while Enders & Schlafke (1965) have observed the pre-implantation stages of pregnancy. The ultrastructure of implantation has been studied in two other species of myomorph rodents: the mouse (Potts, 1966a; Reinius, 1967) and the rat (Enders & Schlafke, 1967). Implantation is taken as beginning when the zona pellucida is lost and the trophoblast is in contact with the uterine epithelium throughout its circumference. This takes place at between 80–100 h post coitum. Previous studies have been made on specimens embedded in paraffin, and the shrinkage which occurs with this method of preservation has caused implantation to appear to begin considerably later than this:Graves (1945) gives it as beginning at 5 days, Ward(1948) as 4 days 8 h.


Development ◽  
1956 ◽  
Vol 4 (1) ◽  
pp. 42-56
Author(s):  
Fritz Strauss

There is little precise information in the literature as to the exact place where the union of the male and female gametes occurs in the genital tract of mammals. Yet it seems that an exact knowledge of the place of fertilization might be of great significance, not only for our understanding of the process of fertilization itself, but in its relation to the manifold problems associated with the limited span of time during which the capacity for fertilization persists in the sperm and egg, and to the physiology of later development and implantation. In most writings about the early development of Man and other mammals, it is assumed that the egg is fertilized in the cephalic part of the oviduct. However, there is still insufficient evidence to justify such general assumptions. It would not be surprising if it should be shown that different species have different topographical positions of the fertilization site correlated for instance with such factors as spontaneous versus induced ovulation.


2019 ◽  
Vol 42 ◽  
Author(s):  
Peter C. Mundy

Abstract The stereotype of people with autism as unresponsive or uninterested in other people was prominent in the 1980s. However, this view of autism has steadily given way to recognition of important individual differences in the social-emotional development of affected people and a more precise understanding of the possible role social motivation has in their early development.


2019 ◽  
Vol 42 ◽  
Author(s):  
Teodora Gliga ◽  
Mayada Elsabbagh

Abstract Autistic individuals can be socially motivated. We disagree with the idea that self-report is sufficient to understand their social drive. Instead, we underscore evidence for typical non-verbal signatures of social reward during the early development of autistic individuals. Instead of focusing on whether or not social motivation is typical, research should investigate the factors that modulate social drives.


Author(s):  
F. G. Zaki ◽  
E. Detzi ◽  
C. H. Keysser

This study represents the first in a series of investigations carried out to elucidate the mechanism(s) of early hepatocellular damage induced by drugs and other related compounds. During screening tests of CNS-active compounds in rats, it has been found that daily oral administration of one of these compounds at a dose level of 40 mg. per kg. of body weight induced diffuse massive hepatic necrosis within 7 weeks in Charles River Sprague Dawley rats of both sexes. Partial hepatectomy enhanced the development of this peculiar type of necrosis (3 weeks instead of 7) while treatment with phenobarbital prior to the administration of the drug delayed the appearance of necrosis but did not reduce its severity.Electron microscopic studies revealed that early development of this liver injury (2 days after the administration of the drug) appeared in the form of small dark osmiophilic vesicles located around the bile canaliculi of all hepatocytes (Fig. 1). These structures differed from the regular microbodies or the pericanalicular multivesicular bodies. They first appeared regularly rounded with electron dense matrix bound with a single membrane. After one week on the drug, these vesicles appeared vacuolated and resembled autophagosomes which soon developed whorls of concentric lamellae or cisterns characteristic of lysosomes (Fig. 2). These lysosomes were found, later on, scattered all over the hepatocytes.


Author(s):  
Eric Hallberg ◽  
Lina Hansén

The antennal rudiments in lepidopterous insects are present as disks during the larval stage. The tubular double-walled antennal disk is present beneath the larval antenna, and its inner layer gives rise to the adult antenna during the pupal stage. The sensilla develop from a cluster of cells that are derived from one stem cell, which gives rise to both sensory and enveloping cells. During the morphogenesis of the sensillum these cells undergo major transformations, including cell death. In the moth Agrotis segetum the pupal stage lasts about 14 days (temperature, 25°C). The antennae, clearly seen from the exterior, were dissected and fixed according to standard procedures (3 % glutaraldehyde in 0.15 M cacaodylate buffer, followed by 1 % osmiumtetroxide in the same buffer). Pupae from day 1 to day 8, of both sexes were studied.


2001 ◽  
Vol 7 (S2) ◽  
pp. 1012-1013
Author(s):  
Uyen Tram ◽  
William Sullivan

Embryonic development is a dynamic event and is best studied in live animals in real time. Much of our knowledge of the early events of embryogenesis, however, comes from immunofluourescent analysis of fixed embryos. While these studies provide an enormous amount of information about the organization of different structures during development, they can give only a static glimpse of a very dynamic event. More recently real-time fluorescent studies of living embryos have become much more routine and have given new insights to how different structures and organelles (chromosomes, centrosomes, cytoskeleton, etc.) are coordinately regulated. This is in large part due to the development of commercially available fluorescent probes, GFP technology, and newly developed sensitive fluorescent microscopes. For example, live confocal fluorescent analysis proved essential in determining the primary defect in mutations that disrupt early nuclear divisions in Drosophila melanogaster. For organisms in which GPF transgenics is not available, fluorescent probes that label DNA, microtubules, and actin are available for microinjection.


2019 ◽  
Vol 50 (1) ◽  
pp. 1-6
Author(s):  
Katja Corcoran ◽  
Michael Häfner ◽  
Mathias Kauff ◽  
Stefan Stürmer

Abstract. In this article, we reflect on 50 years of the journal Social Psychology. We interviewed colleagues who have witnessed the history of the journal. Based on these interviews, we identified three crucial periods in Social Psychology’s history, that are (a) the early development and further professionalization of the journal, (b) the reunification of East and West Germany, and (c) the internationalization of the journal and its transformation from the Zeitschrift für Sozialpsychologie to Social Psychology. We end our reflection with a discussion of changes that occurred during these periods and their implication for the future of our field.


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