Testicle fetal abdomen to the inguinal ring and beyond to the inguinal canal and into the scrotum. In most cases (97% full-term, 70% preterm), both testes have descended by birth. In most other cases, only one testis fails to descend (cryptorchidism) and that will probably express itself within a year. The testes grow in response to the start of spermatogenesis. Size depends on lytic function, sperm production (amount of spermatogenesis present in testis), interstitial fluid, and Sertoli cell fluid production. After puberty, the volume of the testes can be increased by over 500% as compared to the pre-pubertal size. Testicles are
Users' Guides to the Medical Literature Users' Guides to the Medical Literature The Users’ Guides to the Medical Literature is a series of articles originally published in the "Journal of the American Medical Association", later rewritten and compiled in a textbook, now in its third edition. The guides provide practical, clinician-friendly advice on all aspects of evidence-based medicine. During the late 1970s a group of clinical epidemiologists at McMaster University including Dr. David Sackett prepared a series of articles to assist clinicians interpreting clinical research. These articles, introducing the term "critical appraisal", appeared in the "Canadian Medical Association Journal" beginning in 1981. In 1990 Dr. Gordon