The SAM technique involves invaginating and tacking the tissues first, in order to previsualize the final result, before making any surgical incisions to the breast.
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As the invaginating synapses from horizontal cells are made onto cone terminals, the center-surround antagonism of cones is thought to be more reliably present in cone terminals.
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Both postulated mechanisms depend on the protected environment provided by the invaginating synapses that horizontal cells make onto cones. The first postulated mechanism is a very fast ephaptic mechanism that has no synaptic delay, making it one of the fastest inhibitory synapses known. The second postulated mechanism is relatively slow with a time constant of about 200 ms and depends on ATP release via Pannexin 1 channels located on horizontal cell dendrites invaginating the cone synaptic terminal. The ecto-ATPase NTPDase1 hydrolyses extracellular ATP to AMP, phosphate groups, and protons.
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The hypha narrows as it passes through the cell wall and then expands on invaginating the cell. A thickened, electron-dense collar of material is deposited around the hypha at the point of invagination. Further, the host cell wall becomes highly modified in the invaginated zone. Inclusions normally present in plasma membrane are absent, and the outer layer contains more polysaccharide.
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This will become a microsphere. Due to metabolic reaction, osmotic pressure will build up inside the microsphere, and this will generate a force for invaginating the membrane, and ultimately division. In fact, this is close to the cell division of cell wall-less bacteria, such as Mycoplasma. Continuous reactions will also invariably produce variable polymers that can be inherited by daughter cells.
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As a result of these recent findings in molecular biology, the label mesozoan is now often applied informally, rather than as a formal taxon. Some workers previously classified Mesozoa as the sole phylum of the lonely subkingdom Agnotozoa. Cavalier-Smith argued that at least some of the mesozoans are in fact protistans, not animals. In the 19th century, the Mesozoa were a wastebasket taxon for multicellular organisms which lacked the invaginating gastrula which was thought to define the Metazoa.
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They named this cell division gene ftsZ. In 1991 Bi and Lutkenhaus used immunogold electron microscopy to show that FtsZ localized to the invaginating septum at midcell. Subsequently, the Losick and Margolin groups used immuno- fluorescence microscopy and GFP fusions to show that FtsZ assembled Z rings early in the cell cycle, well before the septum began to constrict. Other division proteins then assemble onto the Z ring and constriction occurs in the last part of the cell cycle.
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When its development is contrasted to the cidaroid sister subclass Euechinoidea, E. tribuloides becomes a very interesting organism from the standpoint of developmental and evolutionary biology. In euechinoid embryonic development, e.g. in the purple sea urchin, the micromeres comprise a set of four small cells that reside at the base of the vegetal plate. They are a "precociously invaginating lineage", meaning that they move into the blastocoel just prior to gastrulation; these four cells then eventually give rise to the larval skeleton.
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Where an anthozoan lives in a cave or other dark location, the symbiont may be absent in a species that, in a sunlit location, normally benefits from one. Anthozoans living at depths greater than are azooxanthellate because there is insufficient light for photosynthesis. White black coral Leiopathes glaberrima with white sea anemones below, both azooxanthellate, deep water species With longitudinal, transverse and radial muscles, polyps are able to elongate and shorten, bend and twist, inflate and deflate, and extend and contract their tentacles. Most polyps extend to feed and contract when disturbed, often invaginating their oral discs and tentacles into the column.
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While not every obese male has the buried penis condition, 87% of men that received surgical treatment for buried penis were reported to be obese. Significant overlying abdominal fat can also create an environment that encourages bacterial and fungal growth. Obesity can also increase the likelihood of the development of type II diabetes mellitus, which is characterized by increase susceptibility to infections, making it difficult to successfully and promptly manage the buried penis condition. Such recurring infections can also lead to scar contracture, which can cause the prepubic skin to shift over the shaft and glans, thus invaginating the shaft's skin and leading to a buried penis.
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