In early bell stage, FGF18 was found in both inner/outer enamel epithelial cells and dental sac cells,as well as in osteoblast and chondrocyte,and weak staining in dental papilla cells, negative staining in stratum intermedium and stellate reticulum cells.
Tooth eruption requires the presence of the dental follicle, a loose connective tissue sac that surrounds the enamel organ, which is origined from the ectomesenchyme. It is critical in tooth eruption and formation of periodontal tissue.
At cap stage, Msxl could induce BMP-4 to play a role in the differentiation of odontoblast, and Msx2 could induce differentiation of dental papilla cells, dental sac cells and enamel epithelium cells, and it also initiated the apoptosis of enamel knots.
Results The number of Ki-67+ cells in epithelial lining is related to that of S-100+ cells in cyst wall(P<0.05), however, there is no correlation between Ki-67+ cells and S-100+ cells in epithelial lining (P>0.05).
The cystic occurred as three variants: (1) simple unicystic 7(50%) ,(2) cyst associated with odontoma 4(28.6%),(3) ameloblastomatous 3(15.8%) and neoplasms showed ameloblasfibromatous or adenomatoid odontogenic tumor.
Most embryo sacs degenerated, and only about 4.5% of the ovules contained a normal embryo sac with an egg cell, two synergids, three antipodal, and a central cell containing two polar nuclei.
Reserve nutrients were accumulated by the musculocutaneous sac elements at the procercoid stage and, later, by the glandular and tegumental cells.
New data have been considered concerning the previously unknown intraembryonic hemopoietic organ in mammals, a region of aorta-gonad-mesonephros arising in embryogenesis simultaneously with the yolk sac.
Cytophotometric measurements of Feulgen-DNA were carried out in the nuclei of embryo sac cells of Haemanthus albiflos and Ornithogalum caudatum.
Formation of nonreduced gametes in the embryo sac was induced by low temperature (4-7°C).
Thyroglossal duct carcinoma, which is usually diagnosed postoperatively, is a rare malignant tumor arising in the thyroglossal duct cyst.
Two cases were diagnosed as thyroglossal duct cyst prior to the operation, the remaining one as dermoid cyst.
Primary thyroglossal duct carcinoma should conform to the following criteria: localization of the carcinoma to a clearly demonstrable thyroglossal duct cyst or tract; clinically or histologically confirmed absence of carcinoma of the thyroid gland.
The obligatory heterogenous tissue cyst-forming coccidia of the genus Sarcystosis are regarded as an excellent example of the specific coexistence of two organisms, i.e., the host and parasite.
Of special interest is the parasite's ability to persist in this host at the stage of tissue cyst or sarcocyst.