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JM DeMasi 《Canadian Metallurgical Quarterly》1996,98(1):169; author reply 169-169; author reply 170
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Determinations of oxygen solubility in serum were made utilizing various concentrations of corticosteroids in the serum. Within a certain concentration range dexamethasone and betamethasone caused an increase in oxygen solubility. None of the other steroids tested demonstrated this property.  相似文献   

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[目的] 研究狐尾葛的化学成分. [方法] 系统溶剂萃取及硅胶柱层析后,HPLC纯化获得单体,通过特征反应及波谱数据鉴定化合物的结构. [结果] 从狐尾葛中分离鉴定了2个甾体类化合物,即6 -羟基-豆甾-4-烯-3-酮(I)和6 -羟基-豆甾-4,22(E)-二烯-3-酮(II). [结论] 化合物I、II均首次从该植物中分离得到.  相似文献   

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Steroidal derivatives as IL-1 beta release inhibitors are discussed.  相似文献   

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Sorption of essential oil aroma components, n-alcohols and linalool by starch corn cryotexture was studied. Results show that terpene hydrocarbons of Rosmarinus officinalis L. essential oil are sorbed quantitatively from 0.05% water solution by cryotexture due to hydrophobic interactions with starch polysaccharides. Aroma compounds with oxygen atoms within the molecule are sorbed two times less. A templating effect with glucose, sucrose, maltose and some essential oil components was observed. Sorption of n-alcohols C4, C6, C8, linalool and their mixture with alkyl acetates in concentration 0.5-15 mmol/l was carried out. Individual octanol is sorbed by cryotexture on 88%, hexanol on 20%, linalool on 25%. Butanol is not sorbed at the chosen concentration. Synergism in sorption of hexanol from mixture with octanol and alkyl acetates was observed, while a suppression effect of octanol sorption was found for the same mixture.  相似文献   

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Sediments of the New York Bight were examined for steroidal compounds and found to contain relatively large amounts of coprostanol and 24 beta-ethyl coprostanol. These steroids were found to be derived from sewage, and it is suggested that they be used as sewage tracers in marine sediments.  相似文献   

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The synthesis of the first 17-hydroxymethyl analogue of a steroid hormone of the progesterone-corticoid group, 17-hydroxymethylprogesterone, is described. The starting material for its preparation was 3alpha,12alpha-diacetoxy-5beta-pregnan-20-one and the 17-hydroxymethyl structure was developed by functionalization of the 17-methyl group of a 17alpha-methyl etio ester by a Barton reaction. Neither 17-hydroxymethylprogesterone nor its acetate shows appreciable progestational activity in the Clauberg-McPhail assay.  相似文献   

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The National Acute Spinal Cord Injury Study (NASCIS) 2 and 3 trials are often cited as evidence that high-dose methylprednisolone is an efficacious intervention in the management of acute spinal cord injury. Neither of these studies convincingly demonstrate the benefit of steroids. There are concerns about the statistical analysis, randomization, and clinical end points. Even if the putative gains are statistically valid, the clinical benefits are questionable. Furthermore, the benefits of this intervention may not warrant the possible risks. This paper comments on these two clinical trials.  相似文献   

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Prostaglandin production by methylcholanthrene-transformed 3T3 mouse fibroblasts (MC5-5), human normal fibroblasts (D550), and canine kidney (MDCK) cells was inhibited by several analogues of anthracene, phenanthrene, and benzoflavone. Among the most effective inhibitors of MC5-5's prostaglandin production were anthracene (ID50=1.7 micrometer), 9,10-diaminophenanthrene (ID50=0.48 micrometer), and 7,8-benzoflavone (ID50=0.55 micrometer). Under identical conditions, the ID50's for indomethacin and aspirin were 0.049 and 8.9 micrometer respectively. Production of radioactive prostaglandins by MC5-5 cells from tritiated phospholipids was blocked by 7,8-benzoflavone, but not the release of radioactive arachidonic acid.  相似文献   

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Recent studies from our laboratory indicate that local and (particularly) systemic steroids can modulate the traffic of dendritic cells (DC) through resting and inflamed airway epithelial tissues. The present report focuses upon the T-cell activating properties of DC, which are controlled by granulocyte-macrophage colony-stimulating factor (GM-CSF) signals, and in particular the question of whether the DC-stimulating effects of GM-CSF are susceptible to regulation by steroids. We present evidence that while dexamethasone inhibited GM-CSF-dependent uptake and/or processing of exogenous antigen by DC, it was ineffective in blocking the presentation of preprocessed self antigen to alloreactive T cells in a one-way mixed lymphocyte reaction (MLR). Associated GM-CSF-induced up-regulation of major histocompatability complex (MHC) class II and CTLA4 ligand expression by DC were also unaffected by dexamethasone phosphate (DX), reinforcing the view that the inhibitory effects of steroids on the T-cell activating functions of DC are restricted to steps upstream from presentation of processed antigen to the T-cell receptor (TCR). These findings have potentially important implications in relation to the use of topical steroids in the treatment of atopic asthma, a disease in which local T-cell activation in airway tissue is a key pathogenic factor, and which furthermore is characterized by intense production of GM-CSF within the airway epithelium.  相似文献   

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Rats protect food by dodging horizontally away from a conspecific. Females and males use different movement and stepping patterns to execute a dodge. An unresolved question is whether exposure to ovarian steroids in females is necessary for the development of the female-typical pattern. Females ovariectomized neonatally and prior to puberty use a combination of male and female tactics. Pregnant females, however, use a female-typical pattern of dodging, suggesting that the patterns used by prepubertal ovariectomized females are not due to their increase in body mass. Thus, the contribution of ovarian steroids to the development of female-typical patterns of behavior needs to be studied further at both a behavioral and neural level with regard to the organization of movement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Previous studies by the authors have shown voluntary intracerebroventricular (icv) testosterone self-administration in hamsters (Mesocricetus auratus). Here, the authors compared icv self-administration of 4 anabolic steroids (drostanolone, nandrolone, oxymetholone, and stanozolol) at 0.1, 1.0, and 2.0 μg/μl, each for 8 days. Males (n=8/group) showed the highest levels of operant behavior for injectable steroids (drostanolone, nandrolone) compared with orally active androgens (oxymetholone, stanozolol). For nandrolone, responses on the active and inactive nose-pokes averaged 22.3 ± 4.6/4 hr and 10.7 ± 2.0/4 hr, respectively. Responding for drostanolone was similar. Males self-administering oxymetholone or stanozolol did not prefer the active nose-poke. These data demonstrate that injectable androgens are more reinforcing than oral steroids. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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