[Differential physical growth during the first years of life. III. Body composition].

The present article report the results of longitudinally research, on growth children, of both sex and ages from 0 to 1 year of extrauterine life. We obtained measures that appraisal the muscular and fat tissues: upper arm and leg circumferences; muscle and fat of upper arm areas; triceps, subscapular and supra-iliac skinfolds. Moreover, we report relationship dates between weight and stature, which is a good indicator for morphological body equilibrium.

[Differential physical growth during the 1st year of life. II. Growth of the head].

The corporal segment that display the major growth velocity before and after born is the head; that is, once a baby is born, it represents the fourth part of the stature, it has the greater corporal circumference, and their development is superior than other corporal segments. However, the growth shape of the craniofacial structures is different; so, the growth gradient of brain, is the responsible of the morphological view described previously; the facial structures follow the general growth curve; moreover, the facial bone that contributes with the growth of brain, describes mixed growth gradients. This complex shape of the head growth, requires the existence of growth standards for these structures.

[Differential physical growth during the first year of life. I. Body growth].

Keeping up to date the children growth and development standards, it is a necessity of main order for Health Secretary, because of it is possible an adequate pediatric evaluation. The present study, reports the results of a longitudinal research on growth in children of both sexes and ages from 0 to 1 year of extrauterine life. In all, we got 44 growth measures of the body, head and corporal composition.

[Age of onset of spermaturia (spermache) in 669 Mexican children and its relation to secondary sexual characteristics and height].

The onset of production of spermatozoa (spermarche) indicates the beginning of reproductive capacity in men. With the purpose to establish the age of initiation of spermaturia, we performed a transversal study in 669 Mexican boys aged 9-16 years old, searching for the presence of spermatozoa in the first urine sample during five consecutive days. Besides, physical examination, including Tanner stages for genitalia and pubic hair was practiced.