头孢克洛在健康人体内的药物动力学研究

采用ＨＰＬＣ测定健康志愿者血浆中头孢克洛的浓度。方法简便快速，结果准确。平均回收率为１０２．１８±４．０１％，日间及日内ＲＳＤ均小于６％。血药浓度－时间曲线符合一室模型。     

Epidermal injury stimulates prenylation in the epidermis of hairless mice

Isoprenylation is the covalent attachment of isoprenyl groups, intermediates of the cholesterol biosynthesis pathway, to carboxy terminal cysteine residues of proteins. Numerous proteins are isoprenylated including small GTP binding proteins, trimeric G proteins, and nuclear lamins, and these prenylated proteins regulate a variety of cell functions, including cell growth, cytokinesis, and differentiation. Here, we quantitated protein prenylation and determined which proteins are prenylated in the epidermis of hairless mice by radiolabeling with ³ H-mevalonolactone following acute or chronic epidermal injury. In normal epidermis, four major radiolabeled bands, with molecular weights of 17–26, 48, 54, and 68 kDa, were observed. The levels of each of these bands increased by 24–63% 16 h following acute epidermal injury induced by topical acetone treatment or tape stripping, returning to normal by 24 h. On 2D gel electrophoresis, there were no major differences between the patterns of labeling following barrier disruption. Subacute epidermal injury induced by either acetone or tape stripping twice a day for 7 days and chronic injury induced by feeding an essential fatty acid-deficient (EFAD) diet, also resulted in a significant increase in protein prenylation. As with acute injury, SDS-PAGE and 2D gel electrophoresis did not reveal marked differences in the pattern of protein prenylation. These results demonstrate that the prenylation of proteins in the epidermis is stimulated by injury, suggesting that one or more of these prenylated species may be important in epidermal proliferation or differentiation. Received: 29 May 1996