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21.
In order to identify risk factors for preterm birth in singletons, data from a population-based case control survey on the island of Curacao were re-analysed. Both medical and sociodemographic variables were examined. Overall, a history of previous preterm birth and severe hypertension during the index pregnancy were indicators of adverse pregnancy outcome, in terms of preterm birth. The contribution of sociodemographic factors to the risk of preterm birth is relatively low. 相似文献
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Invasive pulmonary aspergillosis is characterized by radiological signs allowing a correct diagnosis, including differentiation from pulmonary candidiasis, when they are associated with appropriate clinical symptoms (neutropenia and fever persisting despite broad-spectrum antibiotics). In particular the formation of a pulmonary mycetoma in a previously normal lung is one of these signs. Unlike a simple fungus ball (the saprophytic form of aspergillosis), the rounded density of invasive pulmonary aspergillosis consists of sequestrum of devitalized lung tissue owing to blood vessel invasion by Aspergillus hyphae. This morphologic phenomenon is demonstrated in the present case report and is discussed together with the other roentgenological signs of the invasive aspergillosis. 相似文献
25.
The effect of valproic acid on the distribution of gavaged 65Zn in maternal and embryonic tissue of Sprague-Dawley rats was examined 24 h after gavaging of the drug on d 13 of pregnancy. Valproic acid treatment resulted in a significantly higher retention of 65Zn in maternal liver and lower amounts in uterus, placenta and embryos than in controls. Compared to controls, gel chromatography of maternal liver from valproic acid-treated dams showed higher 65Zn counts associated with a protein peak of molecular weight of 6,500, the approximate molecular weight of the Zn-binding protein metallothionein. These results support the idea that the teratogenicity of valproic acid is in part due to an induction of embryonic Zn deficiency secondary to a drug-induced sequestering of Zn into maternal liver that results in a decrease in maternal plasma Zn and subsequent reduction in embryonic Zn uptake. 相似文献
26.
K G Kristinsson B Jansen U Treitz F Schumacher-Perdreau G Peters G Pulverer 《Journal of biomaterials applications》1991,5(3):173-184
Polymer-associated infection is a problem of increasing importance in modern medicine. In a new approach to prevent such infections we have modified polyvinylfluoride (TEDLAR) films by graft copolymerization with N-vinylpyrrolidone to which iodine can be complexed. Grafting reaction was performed by the preirradiation technique using an electron accelerator. Grafted films were then treated in Lugol's solution for at least 24 h. Release of free iodine from the films was determined either by titration or using the agar disc diffusion test, showing an iodine release for up to 4-5 days. The antimicrobial activity of the films was tested in bacterial adhesion measurements. Bacterial and fungal cells in the range of 10(3) to 10(6) cfu/cm2 polymer were found on control samples without iodine, whereas on iodine-complexed films no viable cells could be detected at least for 5 days or even longer. Thus, microbial adhesion and growth can be inhibited by iodine-containing polymers. 相似文献
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M. Ono C. G. Winearls N. Amos D. Grennan A. Gharavi D. K. Peters J. G. P. Sissons 《European journal of immunology》1987,17(3):343-349
Four human monoclonal rheumatoid factors (MRF) were used to raise a panel of mouse monoclonal antibodies (mAb) which were selected in a solid-phase radioimmunoassay for binding to MRF but not normal IgM. Three mAb, each raised against a different MRF, bound to the majority of MRF and also to most polyclonal RF. Four other mAb bound selectively to the MRF against which they were raised and to no other MRF, and rarely to any polyclonal RF. Competition studies using cold and radiolabeled mAb further indicated that these mAb recognize distinct and different epitopes on MRF. RF activity of MRF was inhibited by 3 of the 4 mAb binding to a single MRF and 2 of the 3 mAb binding to multiple RF. It was thus concluded that of this panel of mAb 3 recognized cross-reactive idiotopes and the remainder demonstrated highly restricted idiotopes on MRF. These mAb identified MRF idiotopebearing cells in the peripheral blood of 3 of the MRF donors (and a further subject with type II essential cryoglobulinemia), with a frequency ranging from 0.3–10% of all mononuclear cells with the mAb to restricted idiotopes or 1.5–17% with mAb to cross-reactive idiotopes. These anti-idiotopic mAb should thus provide a highly specific means of identifying and monitoring MRF-producing cells in vivo. 相似文献
29.
E J Laurensse H M Pinedo G J Peters 《Clinica chimica acta; international journal of clinical chemistry》1988,178(1):71-78
A new sensitive assay for pyrimidine nucleoside phosphorylase using non-radioactive substrates is described. With the natural substrate uridine (UR) and the analog, 5'-deoxy-5-fluorouridine (5'dFUR) conditions have been optimized to measure the product formation with reversed-phase high-performance liquid chromatography. Using automated injection large series of samples may be analyzed. The assay for UR phosphorylase appeared to be comparable to existing methods with radiolabeled UR as substrate regarding sensitivity and linearity. The assay has been used to measure kinetic parameters for 5'dFUR and UR in two cell lines from intestinal origin. 相似文献
30.
Mammography is important in women who elect lumpectomy and radiation therapy for breast carcinoma: to record the preoperative state, to assess the completeness of resection, and to detect recurrences and second primaries. Mammography of these patients, however, is difficult since surgery and irradiation may cause changes simulating carcinoma. This article describes the findings in the postsurgical and irradiated breast and the difficulty of differentiating the changes from recurrent carcinoma. It also illustrates the findings in recurrences and second primaries. 相似文献