细胞功能测定

The development of techniques for culturing postimplantation mouse embryos has opened up the possibility of continuous observation of embryonic development in vitro. Current methods have supported extensive growth and morphogenesis of the mouse embryo from the stage of gastru ...

Because transgenesis via embryonic stem (ES) cells has become so topical in recent years, there have been a plethora of technical accounts of how to produce chimeras by introducing these cells into the preimplantation mouse conceptus, both using and avoiding micromanipulation (1–5). In the ...

Exo ovo culture of avian embryos is a technique for long-term culturing of embryos outside of their own shell and shell membranes. The problem of how to gain access to the avian embryo while allowing it to grow normally has been the subject of many studies (1). Avian embryos are subjected to various environ ...

Avian embryos provide all sorts of opportunities for the study of higher vertebrate development, especially because an experimental model, in which cells from two species are combined, has been proposed as the basis of a marking technique (1,2). Cell-marking techniques are essential in de ...

The word chimera originally referred to a mythological beast with the head of a lion, the body of a goat, and the tail of a serpent, but it has come to mean any individual made up of the parts of more than one individual. Transplantation chimeras, which can be made in many species and sometimes between species, are fo ...

Lipid-soluble dyes have been found to be useful markers for studying cell lineages in embryos (1,2). They have the advantage of diffusing into or across the plasmalemma, eliminating the need for microinjection. DiI (1,1 dioctadecyl 3,3,3′,3′ tetramethylindocarbocyanine perchlorat ...

Classical fate mapping approaches in any embryo typically involve labeling of single cells with nondiffusible dyes by pressure or iontophoretic microinjection followed by tracing the fate(s) of those cells and their descendants throughout development. The limitation of any app ...

Cell lineage studies reveal what kinds of tissues descend from a single cell or specific region of an embryo. By defining precisely from which cells the various tissues and organs arise one can elucidate the mechanisms that control body organization, understand morphogenetic movements, ...

Complete or partial embryonic cell lineages are available for several animal model systems. In the case of the nematode Caenorhabditis elegans, the entire embryonic cell lineage has been determined and is largely invariant (1). This makes lineage analysis a potentially useful tool for as ...

One of the virtues of using avian embryos for experimentally analyzing early developmental events is the ease with which they can be cultured and subsequently manipulated and observed. Gastrula- and neurula-stage avian embryos can be cultured for 24–48 h on their vitelline membranes (ace ...

Specific groups of cells in avian embryos can be marked using a variety of techniques and labels. Which type of technique is used depends on the purpose of the experiment. For example, individual cells can be labeled by iontophoretic injection (1) or retroviral infection (2), and clones of cells deri ...

As the next millennium dawns, developmental biology, the study of the processes that give rise to cellular diversity and order within an organism and to the continuation from one generation to the next, has reached a most exciting stage as an experimental science. In particular, in the last two deca ...

The use of genetically modified retroviruses as agents for gene transfer has provided developmental biology with some of its most elegant and compelling research stories of the last few years. The growing recognition of the utility of retrovirally derived constructs is perhaps unsurp ...

In female mammals, one of the two X chromosomes in each and every embryonic cell is randomly inactivated during embryogenesis, leaving only one active X chromosome per cell and thereby maintaining dosage parity with males (1). This natural phenomenon, known as X inactivation or lyonization, p ...

The ideal cell lineage marker is one that can be visualized in living tissues without perturbing development. Exogenously applied dyes are very useful, but in many instances there would be advantages to an endogenously expressed marker. Green fluorescent protein (GFP) appears to have the p ...

The development of fluorescent calcium (Ca2+) indicators has been a very powerful tool for looking at the role of this second messenger in signal transduction. The ability to load these indicators into cells in a nondisruptive manner allow for the visualization of intracellular-free Ca2+ i ...

The chick embryo provides an excellent model system for studying the development of higher vertebrates wherein growth accompanies morphogenesis. (Note: virtually all information given here for the chick embryo is applicable to the quail embryo, and much of it is applicable to embryos of o ...

Current understanding of organ-level vertebrate heart development has been gained primarily from studies of avian and amphibian heart development from whole-mount culture studies and subsequent dissections and serial sections of the heart during different stages of develop ...

Extensive genetic information and transgenic techniques available in the mouse have led to its wide use in studies of mammalian development and models of human disease. A basic limitation of analyzing dynamic developmental processes in mouse embryos is their inaccessibility, becau ...

Optical coherence tomography (OCT) is an attractive imaging technique for developmental biology because it permits the imaging of tissue microstructure in situ, yielding micron-scale image resolution without the need for excision of a specimen and tissue processing. OCT enables r ...