Search PubMed⌕ Search

Biomedical subjects

G Martinez

Publications and source records attributed to G Martinez.

168 records · Page 10Linked to original sources
PubMedDate not supplied

The role of cartilage in osteogenesis in the human fetal vertebral body.

The cartilage canals of the thoracic and lumbar vertebrae of fetuses ranging in crown-rump (C.R.) length from 33 to 180 mm were examined under light microscopy. The activity of the cells within these canals contributed to the anterolateral growth of the vertebral body. Bone formation was seen to commence in the center of the vertebral body. The cells of the connective tissue contained within the cartilage canals appeared to participate in the process of osteogenesis in multiple, discrete foci. In five-month-old fetuses, periosteal bone was noted on the anterior and posterior surfaces of the vertebral body, and calcification in the walls of the cartilage canals gave the histologic appearance of bone spicules.

Cartilage↗
PubMedDate not supplied

Age differences between minors who give birth and their adult partners.

The role of adult men in adolescent childbearing has received heightened attention in recent years, and a new policy efforts have focused on statutory rape laws as a way to reduce adolescent childbearing. Analyses of the 1988 National Maternal and Infant Health Survey indicate, however, that these policies would not apply to most teenage births. Among mothers aged 15-17 who had a child in 1988, 27% had a partner at least five years older than themselves. In addition, since 23% of minors with older partners were married at the time of the infant's birth, 21% of babies born to unmarried minors were fathered by substantially older men. While births to young mothers and older men raise social concerns, these births make up a small share of all teenage childbearing: Only 8% of all births to 15-19-year-olds are to unmarried minors with a partner five or more years older.

Adolescent↗
PubMedDate not supplied

[Histomorphology of secondary cartilage in human fetal mandibles].

The aim of this study was to provide a histomorphological analysis of some secondary cartilages of mandible and temporal bone as observed in human fetuses 18-22 weeks old. The behavior of cartilage was studied in both these regions, which were decalcified, cut at 10 mu, stained with Mallory staining and examined by optical microscopy. In mandible symphysis menti and condylar cartilage were described. The symphysis appeared to be formed by a fibrous cartilagineous structure surrounded by membranous bone. This structure seems be round in the caudal sections and ovoidal in the rostral sections with the major axis perpendicular to the mean sagittal plane. Meanwhile the condyle is formed by secondary cartilage which may be appreciated in this development stage 5 zona. Secondary cartilage was observed also in the temporal bone nearby the primitive glenoid fossa. The development and the importance of these cartilagineous structures are discussed.

Abortion, Spontaneous↗