Khat chewing is a widespread habit that has a deep-rooted socio-cultural tradition in East Africa and in the Middle East. Although a number of investigations have been carried out using cathinone, the psychoactive component of khat, these may not wholly reflect the behavioral effects observed after administering khat in a dosage similar to those used traditionally. The aim of the present study ...

Reproductive behavior in male rodents is made up of anticipatory and consummatory elements which are regulated in the brain by sensory systems, reward circuits and hormone signaling. Gonadal steroids play a key role in the regulation of male sexual behavior via steroid receptors in the hypothalamus and preoptic area. Typical patterns of male reproductive behavior have been characterized, howeve...

Previous behavioral studies have indicated that the nucleus accumbens (NAc) shell of a male rat is involved in its sexual behavior; however, no previous studies have investigated neuronal activities in the male rat NAc shell during sexual behavior. To investigate this issue, we recorded single unit activities in the NAc shell of male rats during sexual behavior. Of 123 NAc shell neurons studied...

The fossil bacula, or os penis, constitutes a rare subject of study due to its scarcity in the fossil record. In the present paper we describe five bacula attributed to the bear Indarctos arctoides Depéret, 1895 from the Batallones-3 site (Madrid Basin, Spain). Both the length and morphology of this fossil bacula enabled us to make interpretative approaches to a series of ecological and etholog...

Several indices of sexual behavior were characterized for male rats of the Lewis (LEW), Sprague-Dawley (SD) and Fischer (F344) strains. Males were permitted access to a receptive female of their own strain for five 50-min sessions every fifth day. LEW males emitted longer latencies (first mount, intromission, ejaculation and post-ejaculatory interval) and lower frequencies (mounts, intromission...

Complex genitalia occur in many arthropods and in some species extreme female morphologies lead to serious mechanical difficulties for males. Tephritid flies offer examples of such complex genitalia. Because of their economic importance and the extensive use of sterile male releases for tephritid control in Texas and Mexico, studies have been done on various aspects of their basic reproductive ...

background : despite the high incidence and prevalence of cts, there is no exclusive data about normal values increment of motor and sensory distal latencies of median nerve at wrist according to age. this research was done in electrodiagnosis lab of physical medicine & rehabilitation ward in nemazi hospital in shiraz between 1374-1379. material and methods : this study was performed on 1200 ca...

1. Failure of the female to become pregnant (Repeat Breeding Syndrome); 2. Failure to maintain pregnancy after breeding and conception (early embryonic death, fetal loss or abortion); 3. Failure to complete breeding because of physical or behavioral problems (intromission difficulties, refusal of the male); 4. Observed abnormalities in the genitalia (abnormal conformation or lesions of the vulv...