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A case report of radionuclide bone scan findings in a patient with peroneus brevis tendonitis is presented. Peroneal tendonopathy is a common cause of lateral ankle pain. Although magnetic resonance imaging (MRI) findings have been described in the literature, we know of no other detailed report of three-phase bone scan findings, which we believe can provide an alternate means to diagnose this condition. The positive findings consist of a curvilinear band of increased activity that corresponded to the anatomic position of the peroneus brevis tendon and was detected only on the first two phases of the study. 相似文献
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We have studied the metabolism of VP-16-213 (etoposide, VP-16), an antitumor agent, by mouse liver microsomes to reactive intermediates and the subsequent covalent binding to microsomal proteins. This metabolism was shown to involve the O-demethylation of VP-16 and resulted in the formation of a 3',4'-dihydroxy derivative (DHVP-16) which was identified by both HPLC and mass spectrometry. The formation of DHVP-16 was cytochrome P-450-mediated as indicated by its dependence on NADPH, its increased production following treatment of mice with phenobarbital, and its marked inhibition by SKF-525A and piperonyl butoxide. Furthermore, DHVP-16 formation required oxygen. Microsomal incubation of VP-16 resulted in an irreversible binding of the drug to the proteins, which was also shown to be cytochrome P-450 dependent. The covalent binding of the VP-16 metabolite(s) was inhibited by DHVP-16 in a dose-dependent fashion, suggesting that the reactive intermediates that bound to proteins were derived from DHVP-16. Electron spin resonance studies indicated that the same semiquinone radical was formed during enzymatic (oxidation or reduction) metabolism of DHVP-16 and the o-quinone derivative of VP-16 (VP-16-Q). VP-16-Q and its semiquinone radical are suggested to be the bioalkylating species. 相似文献
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Sinha D Karri K Arunkalaivanan AS 《European journal of obstetrics, gynecology, and reproductive biology》2007,133(1):4-11
Botulinum toxin (BTX) is a neurotoxin produced by bacterium clostridium. It is the most poisonous naturally occurring substance known to mankind. The neurotoxin binds to the peripheral cholinergic terminals and inhibits acetylcholine release at that junction leading to flaccid paralysis. This process appears to offer an attractive therapeutic option, filling the void between anticholinergics and surgery in cases of neurogenic and idiopathic detrusor overactivity, detrusor sphincter dyssynergia (DSD), interstitial cystitis and pelvic pain. This article reviews the application of Botulinum toxin A in these conditions. 相似文献
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The plasma clotting factors used to treat hemophiliacs who have developed inhibitory antibodies have a shared history of limited clinical safety and utility. To improve on existing bypass factors, we have developed a reversibly acylated form of human plasma factor Xa capable of providing a time-dependent release of procoagulant activity. Factor Xa was treated with p-amidinophenyl p'-anisate to generate anisoyl Xa. The chemical modification of the protein involves acylation of the active site serine residue of factor Xa. Anisoyl Xa deacylated in a time, pH, and temperature-dependent manner. Active factor Xa generated on deacylation of anisoyl Xa exhibited amidolytic and prothrombinase complex activities in in vitro assays, the level being comparable to those of untreated factor Xa. When Anisoyl Xa was infused into rabbits, active factor Xa was generated on deacylation of the acylated enzyme, which shortened the activated partial thromboplastin time (APTT) in a dose-dependent manner. The duration of effect on rabbit APTT could be directly correlated to the level of human plasma factor Xa. Because anisoyl Xa bypasses the "tenase" complex that is compromised in hemophilia A and B and is unaffected by inhibitory antibodies, it has the potential to be used as an effective bypass therapy. 相似文献
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The hemolytic plaque assay technique can be used to detect specific hormone release from single pituitary cells. Using antisera raised against murine GH or rat PRL, we have enumerated the active lactotropes and somatotropes from male and female rat pituitary glands. These studies reveal sex-related differences in the number of cells exporting GH and PRL among anterior pituitary cells in culture. In the presence of human GH-releasing factor (hGRF), the mean percentage of GH cells was 53% in males and 30% in females (P less than 0.005). The mean percentage of PRL cells was 15% in males and 39% in females (P less than 0.008). These values were not significantly altered when hGRF was omitted. The sum of GH and PRL cells identified in separate plaque assays significantly exceeds the number obtained when GH and PRL cells were determined concurrently with a simultaneous plaque assay for both hormones. This difference is dependent on the presence of hGRF, since there was no difference when hGRF was omitted. These data identify the mammosomatotrope in numbers lower than previous reports. By this approach, the mammosomatotrope subpopulation numbers about 5% of all cells in culture. In summary, we demonstrate a sex-related difference in the number of cells exporting GH or PRL among pituitary cells in culture. This difference corresponds with and may underly sex-related differences in the responsiveness of GH and PRL secretion from the pituitary gland. Furthermore, a minor subpopulation of normal pituitary cells appears capable of simultaneous secretion of both GH and PRL. 相似文献
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