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991.
Optically pure (+)- and (-)-trans-stilbene oxide (TSO) enantiomers were administered to immature male Sprague-Dawley rats. (+)-TSO was the more potent inducer of liver microsomal cytochrome P-450-dependent monooxygenases. The greater potency of (+)-TSO may be explained on the basis of stereoselective metabolism since a far greater concentration of TSO was found in liver microsomes of (+)-TSO-treated rats. Furthermore, of the enzymes known to metabolize TSO, cytosolic epoxide hydrolase turned over the (-)-TSO enantiomer at a faster rate, consistent with the greater persistence of the (+)-enantiomer. Although this report is of chiral effects in potency of enzyme induction, stereoselective metabolism (i.e. disposition) rather than inherent structural characteristics (recognition) may be responsible for these effects. 相似文献
992.
A case of generalized eruptive histiocytoma (GEH) was evaluated and examined histopathologically and ultrastructurally. A 24-year-old male had an episode of high fever and drug-induced eruption prior to the appearance of multiple skin lesions. Uniform, red to dark-red papular lesions appeared on his cheeks and then became generalized. The lesions were composed of a massive dermal infiltrate of histiocytes, which had oval nuclei and amphophilic cytoplasm. The cytoplasm contained unique annular structures, myeloid bodies and vacuoles. The specificity of these structures is as yet unknown. Reactive stimulation rather than neoplastic proliferation may be a causative factor in GEH. 相似文献
993.
The promoting effect of the Chinese medicinal herb, Wikstroemia chamaedaphne and Tung oil extracts (WC and HHPA) on carcinoma of uterine cervix induced by HSV-2 or MCA in mice was studied. The results showed that WC and HHPA extracts were not carcinogenic themselves. After carcinogen HSV-2 and MCA treatment, WC and HHPA were added separately. The inducing rates by HSV-2 increased from 7.4% to 21.1% and 26.3%, those by MCA increased from 56.5% to 82.8% and 84.4%. There was a significant difference between the combined groups and groups with HSV-2 or MCA only. The experimental results suggest that these two kinds of extracts play a promoting effect on carcinogenesis. The relation between the carcinogenesis of uterine cervix or nasopharynx and WC or HHPA extracts is discussed. 相似文献
994.
A 44-year-old female with Cushing's disease associated with a pituitary macroadenoma was treated with cyproheptadine, 24 mg per day, after partial surgical resection of the tumor. A large residual tumor remained. There was no clear suppression of serum and urinary cortisol during therapy, but both levels rose markedly to beyond pre cyproheptadine levels, on withdrawal of the drug. This is the first report on the use of cyproheptadine in Cushing's disease associated with a pituitary macroadenoma. The response in this patient indicates an influence of cyproheptadine on ACTH secretion by the macroadenoma. 相似文献
995.
996.
997.
Familial apoceruloplasmin deficiency associated with blepharospasm and retinal degeneration 总被引:16,自引:0,他引:16
A 52-year-old woman had a newly recognized disorder of familial hypoceruloplasminemia, blepharospasm, retinal degeneration, and high-density areas in CT of the basal ganglia and liver scan. Immunofixation electrophoresis disclosed apoceruloplasmin deficiency. Kinetic, x-ray analysis, and histochemical study showed accumulation of iron in liver and brain, but not of copper. Intestinal copper absorption was reduced, but liver uptake was increased. Ceruloplasmin is involved in iron metabolism, and the findings suggest that hypoceruloplasminemia due to lack of apoceruloplasmin was causally linked to the iron deposition in basal ganglia and other organs, leading to blepharospasm and retinal degeneration. 相似文献
998.
999.
A Birkenfeld D Navot Y Ezra A Ron J G Schenker 《European journal of obstetrics, gynecology, and reproductive biology》1987,25(3):221-229
The effect of estradiol valerate and allylestrenol on the endometrial transformation of five hypergonadotropic hypogonadic women was evaluated. Estradiol valerate was administered throughout the whole induced cycle (28 days), while allylestrenol was added during the second half of the cycle. Endometrial biopsies were performed during allylestrenol treatment and were evaluated histologically. Samples of endometrium were also subjected to one-dimensional SDS electrophoresis. Of ten biopsies performed, only one was interpreted to be in-phase, while the others were dated proliferative (4 biopsies) or showed abortive or out-of-phase secretory transformation. The highest mean serum progesterone level, detected under allylestrenol treatment, was 1.5 ng/ml. Protein electrophoresis demonstrated relative sequential changes in the protein patterns of the 115 kDa and 150 kDa protein bands. It is concluded that allylestrenol, although having gestagen properties, may not be efficient for the induction of an adequate secretory transformation of human endometrium in the absence of ovaries. 相似文献
1000.
4-Aminopyridine (4-AP) induced an atropine- and tetrodotoxin (TTX)-insensitive contraction (resistant contraction), in a concentration-dependent manner, in the isolated jejunum of rabbits. The failure of specific antagonists of histamine, serotonin and substance P to affect this resistant contraction ruled out the participation of histamine, serotonin and/or substance P. Antiserum against neuropeptide Y (NPY) reduced this resistant contraction in a concentration-dependent manner and inhibited the action of 4-AP totally at a high concentration (1.25% dilution) whereas normal serum lacked this ability. This suggested that the release of NPY was involved in this 4-AP-induced resistant contraction. Radioimmunoassay of NPY-like immunoreactivity in isolated synaptosomal preparations indicated that 4-AP possessed the ability to induce the release of NPY. However, guanethidine did not affect the actions of 4-AP, indicating that NPY is released mainly from non-adrenergic nerves. Our results indicate that 4-AP induces the release of NPY from non-adrenergic nerves to produce an atropine- and TTX-resistant contraction in the isolated jejunum of rabbits. 相似文献