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11.
To improve the drug permeation into and/or across the skin, essential oils extracted from Alpinia oxyphylla (AO) were evaluated using in vitro and in vivo permeation techniques with Wistar rats as the animal model. Hydrocarbons and oxygenated sesquiterpenes were the major components in the lower-polarity fraction (AO-1) and higher-polarity fraction (AO-2), respectively. Permeation of indomethacin was significantly enhanced after treatment with AO-1 and AO-2 in the in vitro and in vivo studies. AO-2 generally showed a higher ability to promote drug permeation compared to AO-1. The increment of skin/vehicle partitioning may be the predominant mechanism for this enhancing activity. Both transepidermal water loss (TEWL) and colorimetric evaluation showed limited irritation to skin by AO essential oils at the macroscopic level. Human skin fibroblasts were used to investigate the in vitro screening of skin toxicity. AO-1 slightly increased prostaglandin E(2) (PGE(2)) formation from skin fibroblasts. A striking result was observed with AO-2, which greatly inhibited the release of PGE(2). Moreover, both AO essential oils had no statistically significant effect on PGE(2) release by human lung epithelial cells. The results of this study indicate that skin disruption and inflammation do not necessary correspond to the enhancing efficiency of the enhancers tested.  相似文献   
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Summary We present the case of a sacrococcygeal chordoma which recurred 15 years after the radical removal as a soft tissue tumor in the gluteal musculature. This tumor consisted of two parts: a chordoma without symptoms of aggressive cellular proliferation and a malignant fibrous histiocytoma. During the following 4 years several local recurrences of the malignant fibrous histiocytoma occurred in the gluteal musculature. The patient finally died of lung metastases. No chordoma tumor tissue was found in the lungs, in the gluteal musculature or in the sacrococcygeal bone area. Histology including electron microscopy revealed no proof of a transition of chordoma into malignant fibrous histiocytoma. It must be assumed that the secondary soft tissue tumor originated from residual chordoma cells which were implanted during the operation of the primary tumor. It remains unclear whether the malignant fibrous histiocytoma arose from mesenchymal stromal cells within the chordoma or directly from primitive neuroectodermal chorda cells which possess the ability to differentiate into a variety of cell types including mesenchymal cells.  相似文献   
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Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16- cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.   相似文献   
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Regulation of macrophage Fc receptor (Fc gamma R)-mediated phagocytic function by histidine-rich glycoprotein (HRG) was investigated. Pretreatment of oil-elicited inflammatory mouse peritoneal macrophages with HRG for 1-3 hr increased their Fc gamma R-mediated binding and phagocytosis of IgG-opsonized sheep erythrocyte conjugates (EA). A significant reduction of Fc gamma R-dependent EA binding and phagocytosis occurred after pretreatment of macrophages with HRG for more than 8 hr. These results indicate that HRG is capable of modulating Fc gamma R expression in a biphasic fashion, which directly affects the overall efficiency of phagocytosis. HRG differentially regulated the functions of Fc gamma R subclasses. For example, HRG reduced the efficiency of Fc gamma RII (Fc gamma 2b/gamma 1R)-dependent phagocytosis of erythrocytes conjugated with monoclonal IgG2b or IgG1 by macrophages pretreated with HRG for 24 hr. However, when similar studies were performed using erythrocytes coated with monoclonal IgG2a, HRG was less effective in inhibiting Fc gamma RI (Fc gamma 2aR)-dependent phagocytosis. As an HRG-binding glycosaminoglycan, heparin failed to block the regulatory function of HRG on macrophages. Similarly, interferon-gamma (IFN-gamma) was not capable of blocking the functional activity of HRG. These studies suggest that HRG regulates macrophage function via a novel pathway different from that of heparin or IFN-gamma.  相似文献   
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Smoking has become a major issue for public health policy in recent years. This paper deals with the economic aspects of smoking. First, we outline the basic concepts of welfare economics which subsequently are used as the normative framework of the analysis. In particular, we stress the role of efficiency as a criterion for economic policy evaluation. Second, we demonstrate that smoking is associated with several market failures, notably externalities and dependency/addiction (non-rational behavior). Third, costs and benefits of smoking are considered. We argue that the benefits of smoking are the satisfaction (utility) which the consumers derive from it rather than the employment effect of producing tobacco products or the revenues of the excise tax on these products. A general model for estimating the costs of smoking is developed and various cost concepts are discussed. Empirical cost estimates are presented for Switzerland. In 1976, estimated social (economic) costs of smoking were between 560 and 800 million Swiss francs while the external costs were between 140 and 260 million francs. Contrary to a widely held belief, smoking hardly influenced health care costs because the higher medical care costs of smokers during their lifetime are offset by their reduced life expectancy. The last section deals with intervention strategies to reduce smoking: anti-smoking publicity, advertising restrictions, and taxation. We discuss these three instruments on a conceptual level and summarize previous empirical studies. The main results are: (1) Both publicity and taxation offer a considerable potential as deterrents of cigarette demand. (2) The results for Switzerland imply that publicity campaigns are likely to be efficient in the sense that expected campaign benefits outweigh its costs.  相似文献   
19.
Equity in the finance of health care: some further international comparisons.   总被引:10,自引:0,他引:10  
This paper presents further international comparisons of progressivity of health care financing systems. The paper builds on the work of Wagstaff et al. [Wagstaff, A., van Doorslaer E., et al., 1992. Equity in the finance of health care: some international comparisons, Journal of Health Economics 11, pp. 361-387] but extends it in a number of directions: we modify the methodology used there and achieve a higher degree of cross-country comparability in variable definitions; we update and extend the cross-section of countries; and we present evidence on trends in financing mixes and progressivity.  相似文献   
20.
蝙蝠葛中的新生物碱——蝙蝠葛新林碱   总被引:3,自引:0,他引:3  
防已科植物蝙蝠葛(Menispermum daurioum DC.)的根茎,即北豆根,是一种重要的中药,具有清热解毒、消肿止痛等功效。已知含有近二十种生物碱,其中五种属双苄基四氢异喹啉类,即蝙蝠葛碱(dauricine,Ⅰ)、蝙蝠葛诺林碱(daurinoline,Ⅱ)、蝙蝠葛新诺林碱  相似文献   
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