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Norethisterone enanthate (NET-En), an established intramuscular long-acting contraceptive agent, has previously been shown to be effective in inhibiting fertility in two rodent species even 4 days after oral ingestion. Pharmacokinetics of NET and NET-En were studied after oral and intramuscular doses in two animal species and a few women. The results suggest that the NET-En was absorbed within a day in all the species after oral dose. The estimates of relative bioavailability ranged from 13 to 51% in rabbits, monkeys, and women. The elimination half-life was 5–10 days. The presence of the active component, NET, in the circulation over the experimental period of 15 days suggests that NET-En could be useful as a long-acting oral pill. The suppression of progesterone levels during the luteal phase of menstrual cycle in women also supports this finding.  相似文献   
974.
The effects of lentinan on peripheral blood mononuclear cell (PBMC) expression of IL-2 receptor in patients with chronic hepatitis B in vitro and in vivo were studied. The expression percentage of IL-2 receptor in 44 patients with chronic hepatitis before treatment was 36.74 +/- 7.74, which was lower than healthy subjects, and was 48.92 +/- 3.79 after 2 months treatment of lentinan, which was approximated the normal control. PBMC from 30 patients with chronic hepatitis B were cultured in vitro with or without lentinan. The percentage of expression IL-2 receptor was 12.81 +/- 2.62 without lentinan and was 35.70 +/- 4.87 in the presence of lentinan. The concentration of lentinan stimulating expression of IL-2 receptor was between 0.2 to 200 g.ml-1. The results suggest that lentinan stimulates expression of IL-2 receptor on PBMC, which is associated with the therapeutic effectiveness of lentinan treatment.  相似文献   
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Species-level identification of Acanthamoeba isolates is difficult and gives little or no indication of the isolate's pathogenicity. We identified two amplification-based genetic markers that were highly correlated with pathogenicity in Acanthamoeba spp. One marker, designed to amplify a 485-bp fragment of the small-subunit ribosomal RNA gene (ssrDNA), was preferentially amplified from the nonpathogenic strains; amplifications from the pathogenic strains yielded anomalous fragments of 650 and 900?bp. A second marker was developed on the basis of the anomalous 650-bp fragment. Primers to this sequence preferentially amplified a noncoding locus (called Ac6) only from the pathogenic strains. These two genetic markers may be useful for identification of pathogenic Acanthamoeba spp. strains.  相似文献   
978.
 Rhabdomyosarcoma (RMS) is occasionally found in the female genital tract, and mostly appears as one of the heterologous mesenchymal components in uterine carcinosarcoma designated as malignant mixed müllerian tumour (MMMT). We examined the biological properties of a pure rhabdomyosarcoma (RMS) cell line designated FU-MMT-3, which was newly established from a surgical specimen taken from a patient with uterine MMMT. We also evaluated c-myc and MYCN gene amplification in three RMS cell lines (including FU-MMT-3) derived from three MMMTs by Southern blot analysis. FU-MMT-3 cells were propagated continuously for 57 serial passages over a 2-year period in vitro. FU-MMT-3 was able to produce tumours demonstrating pure RMS in athymic nude mice. Cytogenetically, FU-MMT-3 showed a triploidy pattern, with complex karyotypic abnormalities including trisomy of chromosome 8. All three RMS cell lines, including FU-MMT-3, showed amplification of the c-myc gene (approximately fourfold to eightfold), while no cell lines demonstrated MYCN gene amplification. FU-MMT-3 is considered to provide a useful system for the study of the biological behaviour of RMS in MMMTs. Extra copies of chromosome 8 and c-myc gene amplification may be associated with the rhabdomyoblastic differentiation in MMMT. Received: 7 January 1997 / Accepted: 2 May 1997  相似文献   
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