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221.
A 12‐year‐old male neutered Miniature Poodle with confirmed pituitary‐dependent hyperadrenocorticism was treated with trilostane. After three doses, it developed clinical and laboratory changes suggestive of isolated hypocortisolism (‘atypical hypoadrenocorticism’), which persisted and progressed for more than 3 months despite immediate withdrawal of the trilostane. The clinical signs of hyperadrenocorticism resolved without further trilostane. After 3 months, prednisolone treatment was started and the clinical signs of hypocortisolism resolved. Prednisolone therapy was required for more than 1 year. Ultrasonography initially demonstrated large hypoechoic adrenal cortices, typical of dogs with hyperadrenocorticism, which then became small and heteroechoic, consistent with the development of adrenal necrosis. Persistent isolated hypocortisolism has not been reported previously as a complication of trilostane therapy. The case is also remarkable for the very short duration of trilostane therapy that elicited this complication. Clinicians should be aware that trilostane therapy may result in adrenal necrosis, even in the very earliest stages of therapy, but prompt action can prevent a life‐threatening situation.  相似文献   
222.
Because the prevailing form of hormone replacement therapy is associated with the development of cancer in breast and endometrial tissues, alternatives are needed for the management of menopausal symptoms. Formulations of Trifolium pratense L. (red clover) are being used to alleviate menopause-associated hot flashes but have shown mixed results in clinical trials. The strobiles of Humulus lupulusL. (hops) have been reported to contain the prenylflavanone, 8-prenylnaringenin (8-PN), as the most estrogenic constituent, and this was confirmed using an estrogen receptor ligand screening assay utilizing ultrafiltration mass spectrometry. Extracts of hops and red clover and their individual constituents including 8-PN, 6-prenylnaringenin (6-PN), isoxanthohumol (IX), and xanthohumol (XN) from hops and daidzein, formononetin, biochanin A, and genistein from red clover were compared using a variety of in vitro estrogenic assays. The IC50 values for the estrogen receptor alpha and beta binding assays were 15 and 27 microg/mL, respectively, for hops and 18.0 and 2.0 microg/mL, respectively, for the red clover extract. Both of the extracts, genistein, and 8-PN activated the estrogen response element (ERE) in Ishikawa cells while the extracts, biochanin A, genistein, and 8-PN, significantly induced ERE-luciferase expression in MCF-7 cells. Hop and red clover extracts as well as 8-PN up-regulated progesterone receptor (PR) mRNA in the Ishikawa cell line. In the MCF-7 cell line, PR mRNA was significantly up-regulated by the extracts, biochanin A, genistein, 8-PN, and IX. The two extracts had EC50 values of 1.1 and 1.9 microg/mL, respectively, in the alkaline phosphatase induction assay. On the basis of these data, hops and red clover could be attractive for the development as herbal dietary supplements to alleviate menopause-associated symptoms.  相似文献   
223.
Solanidine is a steroidal aglycon of potato (Solanum tuberosum L.) glycoalkaloids and a very important precursor for the synthesis of hormones and some pharmacologically active compounds. Glycoalkaloids are hydrolyzed by mineral acid, yielding solanidine. This paper deals with the kinetics of solanidine hydrolytic extraction in different solid-liquid-liquid systems. The dried and milled potato (S. tuberosum L.) vines were used as a source of glycoalkaloids and as the solid phase. The solutions of hydrochloric acid in 2 and 10% (w/v) aqueous acetic acid, in 50% (volume) aqueous methanol, and in 50% (volume) aqueous ethanol were first liquid phase, and the medium for glycoalkaloid extraction from potato vines and their hydrolysis to solanidine. The chloroform, trichloroethylene, or carbon tetrachloride were the second, organic, liquid phase and the medium for solanidine extraction. This procedure combines three different processes: extraction of glycoalkaloids from potato vines, their hydrolysis to solanidine, and the extraction of solanidine, in a single step. The term hydrolytic extraction of solanidine was used for these processes. The purpose of the paper was to choose an optimal solid-liquid-liquid system for solanidine extraction and to define the procedure for its isolation from the organic liquid phase. The best degree of solanidine hydrolytic extraction (DHE) of more than 98% was achieved when 10% (w/v) hydrochloric acid in 50% (volume) methanol were the first liquid phase and chloroform was the second liquid phase, after 90 min. The yield of solanidine (q(S)) under these conditions is calculated to be 0.24 g/100 g of potato vines. Approximately 78% of the maximal possible yield of solanidine was isolated from chlorofom liquid phase. The IR and MS spectra of isolated solanidine were recorded.  相似文献   
224.

Background  

We recently reported that the altitude of origin altered the photic and thermal sensitivity of the circadian pacemaker controlling eclosion and oviposition rhythms of high altitude Himalayan strains of Drosophila ananassae. The present study was aimed at investigating the effects of altitude of origin on the pacemaker controlling the adult locomotor activity rhythm of D. helvetica.  相似文献   
225.
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