Sexual orientation (homo- vs. heterosexuality) is one of many sex differences observed in humans. Sex differences can result from differential postnatal experiences (interaction with parents, environment) or from biological factors (hormones and genes) acting pre- or postnatally. The first option is often favored to explain sexual orientation although it is supported by little experimental evidence. In contrast, many sexually differentiated behaviors are organized during early life by an irreversible action of sex steroids. In particular, the preference for a male or female sex partner is largely determined in rodents by embryonic exposure to sex steroids. The early action of these steroids also seems to affect sexual orientation in humans. Indeed, clinical conditions associated with major endocrine changes during embryonic life often result in an increased incidence of homosexuality. Furthermore, multiple sexually differentiated behavioral, physiological, or even morphological traits that are known to be organized by prenatal steroids, at least in animals, are significantly different in homo- and heterosexual populations. Thus, prenatal endocrine (or genetic) factors seem to influence significantly human sexual orientation even if a large fraction of the variance remains unexplained to date. The possible interaction between biological factors acting prenatally and postnatal social influences remains to be investigated.
Lammert, M., & Timberlake, E. M. (1986). Termination of foster care for the older adolescent: Issues of emancipation and individuation.
Dou, L., E. Bertrand, C. Cerini, V. Faure, J. Sampol, R. Vanholder, Y. Berland, P. Brunet. ... A. Timberlake, B. Sumpio, R. Pfragner, I. M. Modlin, M. Kidd.
Chendrasekhar A, Moorman DW, Timberlake GA. An evaluation of the effects of ... Chittiboina P, Wylen E, Ogden A, et al. Traumatic spondylolisthesis of the ...
Hartmann LC, Radisky DC, Frost MH, et al. Understanding the premalignant potential of ... D'Alfonso TM, Wang K, Chiu YL, et al. Pathologic upgrade rates on ...
Stensland, J., Speedie, S., Ideker, M., House, J., & Thompson, T. (1999). The relative cost of outpatient ... Deal, J. L. (1987). Appraisal and diagnosis of ...
1 2 Howard, S. and Johnson, B. (2000) Resilient and Non-resilient Behaviour in ... 4 De Haan, L., Hawley, D. and Deal, J. (2002) 'Operationalizing family ...
... are not fluent in the language/s of the medical care provider.72 Research ... Anglo-Americans have traditionally placed a great deal of emphasis on the ...
This practical guide thoroughly discusses both well-established and new interventions that are applied to the spine for the purpose of pain relief.
Several versions of Pearson's MyLab & Mastering products exist for each title, including customized versions for individual schools, and registrations are not transferable.
If a picture paints a thousand words, imagine what video can do? Pearson Medical Assisting Videos help users learn the nuances and the details of many medical assisting procedures.