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A set of 20 2-cyanoaziridine-1-carboxamides was synthesized from 2-cyanoaziridine and appropriate isocyanates. These compounds were active against a variety of solid and hematological tumor cells in culture, including strains resistant to doxorubicin and mitoxantrone. Their potencies in these assays correlated with the lipophilicity of substituents. The N-phenyl derivative was more potent and equally effective to imexon, a cyclized 2-cyanoaziridine-1-carboxamide of clinical interest, against cloned fresh human tumors.  相似文献   
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The cell-wall characteristics of Gardnerella vaginalis grown in conventional and biofilm systems were studied by electron microscopy. The gram-positive nature of the cell wall was confirmed. Novel cell-wall particles which appeared to be associated with cell division were also identified, particularly in organisms of biofilm origin.  相似文献   
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BACKGROUND: So far only a few cases of carcinoma in situ of the fallopian tube have been reported, but its detailed clinical and pathologic findings, including cytology, have not been fully described. CASE: A 70-year-old female was admitted to our hospital because of irregular genital bleeding. Endometrial smear revealed a small number of atypical cells with a clear background. Hysterectomy, bilateral salpingo-oophorectomy and omentectomy were performed. Grossly, a grayish white papillary tumor, measuring 1.5 x 1.0 cm, was observed within the lumen of the left fallopian tube. Microscopically, the diagnosis of papillary adenocarcinoma in situ of the left fallopian tube was made according to 1992 International Federation of Gynecologists and Obstetricians fallopian tube staging. CONCLUSION: Although endometrial brush cytology is not sensitive enough to detect a primary carcinoma of the fallopian tube, our case indicates that it may contribute useful information on extrauterine diseases and can detect a stage 0 cancer of the fallopian tube. Clinicians, as well as pathologists, should consider the possibility of fallopian tube cancer if cervical or endometrial cytology shows atypical cells with papillary patterns with a clear background but endometrial curettage cannot prove malignancy.  相似文献   
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Equilibrium dialysis and Scatchard plots were used to establish that human and rabbit paraoxonases both have two calcium binding sites. Independent-site and stepwise constant analyses were used to calculate a higher affinity site (Kd1) of 3.6 +/- 0.9 x 10(-7) M for human A paraoxonase, and 1.4 +/- 0.5 x 10(-8) M for rabbit paraoxonase, and a lower affinity site (Kd2) of 6.6 +/- 1.2 x 10(-6) M for human A paraoxonase, and 5.3 +/- 0.94 x 10(-6) M for rabbit paraoxonase. In both species, the higher affinity sites were found to be essential to maintain hydrolytic activity; complete removal of calcium led to irreversible inactivation. The lower affinity sites were required for catalytic activity, and their binding of calcium was reversible. Experimentally estimated values of Kd2 based on the concentration of calcium required to obtain half the maximum enzymatic activity were 3 microM for human A and B paraoxonases, and also in the order of 3 microM for rabbit paraoxonase, using three different substrates. Calcium was the only metal found that protects against denaturation and also confers hydrolytic activity with these two mammalian paraoxonases.  相似文献   
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The purpose of this systematic study was to provide an up to date and reliable quantitative summary of the relative benefits of various types of chemotherapy (non-platinum vs platinum, single-agent vs combination and carboplatin vs cisplatin) in the treatment of advanced ovarian cancer. Also, to investigate whether well-defined patient subgroups benefit more or less from cisplatin- or carboplatin-based therapy. Meta-analyses were based on updated individual patient data from all available randomized controlled trials (published and unpublished), including 37 trials, 5667 patients and 4664 deaths. The results suggest that platinum-based chemotherapy is better than non-platinum therapy, show a trend in favour of platinum combinations over single-agent platinum, and suggest that cisplatin and carboplatin are equally effective. There is no good evidence that cisplatin is more or less effective than carboplatin in any particular subgroup of patients.  相似文献   
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A diffusion cell with an artificial membrane and the single-pass perfused rabbit ear were used to evaluate the percutaneous absorption of clonazepam from various 2-hydroxyethyl acetate (HEA) patches. The influence on drug permeation of the various type of enhancers (isopropylmyristate, lauryl alcohol, propylene glycol and water) in the patches was tested. A comparison between the two types of systems of percutaneous absorption of clonazepam has been done. The results showed that HEA patches produce controlled uniform drug release, modulated by the addition of enhancers.  相似文献   
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