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The synthesis of new conjugates with inhibitory action on tumour growth is investigated by linking amino functions of proteins compounds (lysozyme and alpha s-casein) through an amide linkage at the carboxylic function of nitrogen mustards (chlorambucil and melphalan). The polychlorambucil amides of lysozyme and alpha s-casein derivatives prepared showed experimental antitumour activity when these conjugates were screened against the experimental P388 leukemia. In the case of the conjugates lysozyme-melphalan, an antitumour activity is observed when the amino function of the drug is combined with the carboxylic functions of the protein contrary to the situation of the free amino function of the drug described into the literature.  相似文献   
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Central venous plasma concentrations of bupivacaine were determined in two groups of 15 parturients each who were given epidural analgesia for labor and vaginal delivery. One group received 10 ml of 0.125% bupivacaine plus epinephrine 1:800,000, the other group received 7 ml of 0.375% bupivacaine plus epinephrine 1:800,000. Plasma concentrations of bupivacaine in the umbilical venous (UV) and the umbilical arterial (UA) blood of their babies were also determined. The mean UA, UV, and maternal central venous (MV) plasma concentrations of bupivacaine differed significantly between the two groups: in patients given 0.375% bupivacaine UA values were 63% higher (P less than 0.01), UV values were 57% higher (P less than 0.01), and the MV values were 34% higher (P less than 0.05) than in patients given 0.125% bupivacaine. The measured plasma concentrations speak in favor of the less concentrated solution of bupivacaine in epidural analgesia for obstetrics. Seven milliliters of bupivacaine 0.375% is suitable for epidural analgesia in obstetrics but a low concentration-low dose technique, using 10 ml of bupivacaine 0.125% plus epinephrine 1:800,000 is safer. It provides good analgesia with minimal or no motor block and is associated with low maternal and neonatal plasma concentrations of bupivacaine, well below toxic levels and, to our knowledge, lower than in any other study.  相似文献   
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OBJECTIVES: Lipoprotein(a) (Lp(a)) and homocysteine (Hcy) are independent cardiovascular risk factors, which have been shown to be lowered by hormone replacement therapy (HRT). In this 2-year study, the long-term effects of raloxifene (Rlx) in two doses, on Lp(a) and Hcy, were studied and compared with the effects of continuously combined hormone replacement therapy (ccHRT). METHODS: In a prospective, randomized, double-blind, placebo-controlled 2-year study, 95 healthy, non-hysterectomized, early postmenopausal women, received daily either oral Rlx 60 mg (N=24) or 150 mg (N=23), ccHRT (conjugated equine estrogens 0.625 mg plus medroxyprogesterone acetate 2.5 mg; N=24) or placebo (N=24). Fasting serum Lp(a) and plasma Hcy concentrations were measured at baseline and at 6, 12 and 24 months. RESULTS: The mean individual changes compared to baseline after 24 months were for Lp(a): Rlx 60: - 5%, Rlx 150: -7%, ccHRT: -34%, placebo: +1% and for Hcy: Rlx 60: -3%, Rlx 150: -4%, ccHRT: -4%, placebo: +6%. ANCOVA was significant for Lp(a) under ccHRT versus placebo (P=0.001) and for Lp(a) under ccHRT versus each of the two Rlx groups (P<0.05). CONCLUSIONS: Long-term treatment with Rlx was not as effective as ccHRT in lowering Lp(a). Although not significant and without an obvious dose-related response, the Hcy values showed the same trend for each treatment arm, which is in line with data reported earlier.  相似文献   
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