Oxidation of different types of 1,4-dihydropyridines with diphenylpicrylhydrazyl (DPP) and benzoyl peroxide (Bz2O2) as free radical oxidizing agents to pyridine derivatives is reported and a mechanism for this oxidation is also proposed.

While the role of estrogens in the maintenance of human breast carcinoma has been firmly established for many years, the sources of this estrogen remain unresolved. Input-output analysis of steroid uptake by breast carcinomas showed no specific uptake of estrogens from blood. Based on the detection of the necessary enzyme systems. Adams and Wong proposed that breast tumors could function as "pa...

Zebra finches have emerged as an outstanding model system for the investigation of the mechanisms regulating brain and behavior. Their song system has proven especially useful, as the function of discrete anatomical regions have been identified, and striking parallels exist between the morphology of these regions and the level of their function in males and females. That is, the structures are ...

BACKGROUND The circulating estrogen concentration elevated gradually along with time after ovariectomy in rats. To explore the source of the increased circulation estrogen, the extragonadal aromatization as well as the synthesis of androgen in the adrenal cortex of the ovariectomized rats was evaluated. METHODS Female rats were divided into twelve groups: 1 month after ovariectomy (OVX1M), OV...

Castrated male quail display intense male-typical copulatory behavior in response to exogenous testosterone but ovariectomized females do not. The behavior of males is largely mediated by the central aromatization of testosterone into estradiol. The lack of behavioral response in females could result from a lower rate of aromatization. This is probably not the case because although the enzymati...