BACKGROUND AND OBJECTIVES Darkening of gray and white hairs occurred in 2 patients with increased exogenous triiodothyronine (T3) due to treatment of myxedema coma in one case and iatrogenic hyperthyroidism in the other. We hypothesized that thyroid hormone may affect the homeostasis of hair follicles. To test our hypothesis and investigate the influence of thyroid hormone on the hair cycle, we...

Long menstrual cycles have been associated with reduced risk of breast cancer and increased risk of osteoporosis. These observations have led to assumptions about the endogenous oestrogen exposure of women with long cycles. However, daily oestrogen profiles in long menstrual cycles have not been described. This paper examines daily urinary oestrogen profiles during the follicular phases of 416 ...

OBJECTIVE The validity of prior studies on the menstrual cycle and suicide attempts assumes that suicidal women accurately describe their cycles. The three objectives of this study were 1) to explore whether prior inconsistencies are due to the effects of sample selection and method of assessment of the menstrual cycle, 2) to assess the relationship between the menstrual cycle phase and suicide...

Cholecystokinin (CCK) is widely distributed in the brain and is known to affect behavioral and physiological functions including anxiety and pain. The expression of CCK has been shown to be regulated by estrogen and to vary during the estrous cycle in rat brain. In the present study CCK was determined in plasma from 25 healthy women (age 25.0+/-3.5) during the menstrual cycle, in the late lutea...

To test the hypothesis that progestin-mediated increases in resting core temperature and the core temperature threshold for sweating onset are counteracted by estrogen, we studied eight women (24 +/- 2 yr) at 27 degrees C rest, during 20 min of passive heating (35 degrees C), and during 40 min of exercise at 35 degrees C. Subjects were tested four times, during the early follicular and midlutea...

Auditory steady-state responses (ASSRs) are widely applied to test brain's ability to follow external stimulation in neuropsychiatric disorders. It is known that ASSRs are related to GABAergic transmission. Female sex steroid homones - both estrogens and progesterone - affect functioning of GABAergic system. However, it is not known how these hormones affect brain's ability to entrain. This stu...

in this study, genital tracts of 20 healthy non-pregnant buffaloes were collected from urmia abattoir.these genital tracts were selected based on their ovaries conditions, half of them were in follicular phase and the other half were in luteal phase. the samples were taken from anterior, middle and posterior regions of the cervix and fixed in 10% buffer formalin. then, histological sections of ...

The present study examined whether the advantage of females on L2 vocabulary recall and acquisition is partly as a result of estrogen secretion or not. In this regard, through volunteer and convenience sampling 15 intermediate EFL female participants aged between 23-31 were selected from the subject pool of 55 participants. The participants were studying at Iranian Language Center located in Ba...

Our objective was to determine if the menstrual cycle affected expiratory resistance developed during progressive incremental exercise in females. Eleven females (age = 19.7 ± 1.1 yr., body mass = 58.9 ± 8.8 Kg, height = 1.65 ± 0.3 m) gave consent to participate in the study. Participants were studied during the follicular (day 7 ± 2 days following onset of menses) and luteal (day 21 ± 2 days f...

Cocaine stimulates gonadotropin (luteinizing hormone) release from the anterior pituitary in humans and in rhesus monkeys, but its acute effects on ovarian steroid hormones are unknown. The acute effects of cocaine and placebo on estradiol and progesterone were studied in 13 drug-naive female rhesus monkeys during the mid-follicular (days 8-10) and the mid-luteal (days 21-23) phases of the mens...