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901.
The advantages of non-prefixed marking for breast reduction are discussed in this paper. The authors use a curved incision modification of the Pitanguy technique, stressing the value of changing the demarcation depending on the skin-gland relationship of each patient.  相似文献   
902.
The interaction between d-amphetamine and ethanol with respect to locomotor activity, stereotyped behavior, and sleeping time was investigated in rats. Ethanol 0.8 g/kg i.p. enhanced and prolonged locomotor activity produced by d-amphetamine 1 mg/kg s.c. The increased motility after 5 mg/kg d-amphetamine was not influenced by alcohol 0.8 g/kg i.p. or 3.2 g/kg orally, but slightly protracted. Stereotyped head and paw movements as well as stereotyped licking, were distinctly strengthened and protracted by 3.2 g/kg ethanol orally. The modified d-amphetamine motility and stereotypies can be explained by alcohol-induced prolongation of the life of d-amphetamine. The effect is produced by alcohol's inhibition d-amphetamine p-hydroxylation in rat liver. After 3.2 g/kg ethanol i.p., the sleeping time of male rats amounted to 153 min. Simultaneous administration of 5 mg/kg d-amphetamine s.c. reduced the sleeping time to 84 min. This is obviously based on a central antagonism.  相似文献   
903.
Kinin B1 receptors are known to be highly induced after inflammatory stimuli in several biological systems. We report that incubation of pig iris sphincter with lipopolysaccharide from Escherichia coli caused a marked and time-related up-regulation of B1, accompanied by a reduction of B2 receptor-mediated contractile responses. The up-regulation of B1 receptors by lipopolysaccharide stimulation was decreased by the inhibitors of protein synthesis, cycloheximide and actinomycin D, and by dexamethasone and the nuclear factor-kappaB (NF-kappaB) inhibitor pyrrolidinedithiocarbamate (PDTC). In addition, lipopolysaccharide-induced up-regulation of B1 receptors in the pig iris sphincter was significantly reduced by the p38 inhibitor 4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole (SB203580) and to a lesser extent by the extracellular signal-regulated kinases 1 and 2 (ERK1/2) blocker 2'-amino-3'-methoxyflavone (PD98059). Molecular biology experiments demonstrated that in vitro incubation with lipopolysaccharide resulted in a time-dependent and remarkable activation of NF-kappaB and of p38 and ERK1/2 mitogen-activated protein (MAP) kinases, in pig iris sphincter preparations. While attempting to verify how MAP kinases are part of the B1 receptor-activated signaling transduction pathways, we observed that PD98059 was able to markedly reduce the contraction induced by B1 receptor activation in lipopolysaccharide-pretreated pig iris sphincter muscle but that this response was only partially decreased by SB203580. Our results extend the previous evidence on the mechanisms underlying the B1 receptor upregulation processes and demonstrate for the first time how this takes place in an ocular tissue, the pig iris sphincter. It is therefore possible to define B1 receptors as therapeutic targets for the treatment of infectious and inflammatory alterations of the eye.  相似文献   
904.
This article describes the legislation that is relevant in the marketing of functional foods in the European Union (EU), how this legislation was developed as well as some practical consequences for manufacturers, marketers and consumers. It also addresses some concrete examples of how the EU's safety requirements for food products have impacted a range of product categories. In the late nineties, research into functional ingredients was showing promising prospects for the use of such ingredients in foodstuffs. Due mainly to safety concerns, these new scientific developments were accompanied by an urgent call for legislation. The European Commission 2000 White Paper on Food Safety announced some 80 proposals for new and improved legislation in this field. Among others, it foresaw the establishment of a General Food Law Regulation, laying down the principles of food law and the creation of an independent Food Authority endowed with the task of giving scientific advice on issues based upon scientific risk assessment with clearly separated responsibilities for risk assessment, risk management and risk communication. Since then, more than 90% of the White Paper proposals have been implemented. However, there is not, as such, a regulatory framework for 'functional foods' or 'nutraceuticals' in EU Food Law. The rules to be applied are numerous and depend on the nature of the foodstuff. The rules of the general food law Regulation are applicable to all foods. In addition, legislation on dietetic foods, on food supplements or on novel foods may also be applicable to functional foods depending on the nature of the product and on their use. Finally, the two proposals on nutrition and health claims and on the addition of vitamins and minerals and other substances to foods, which are currently in the legislative process, will also be an important factor in the future marketing of 'nutraceuticals' in Europe. The cornerstone of EU legislation on food products, including functional foods and nutraceuticals is 'safety'. Decisions on the safety-basis of legislation are based on risk analysis, in which scientific risk assessment is performed by the European Food Safety Authority and risk management is performed by the European Commission, the Member States, and in case of legislation, together with the European Parliament. In the risk management phase, both the precautionary principle and other legitimate factors may be considered in choosing the best way of dealing with an issue. Due to the numerous pieces of legislation applying and to the different procedures to be followed, the process of having 'functional foods' ready for the market is certainly a costly and time-consuming task. However, it may also be clearly worth it in terms of market success and improved consumer health.  相似文献   
905.
Despite numerous studies on women's cardiac health throughout the past decade, the number of female deaths caused by cardiovascular disease still rises and remains the leading cause of death in women in most areas of the world. Novel studies have demonstrated that cardiovascular disease, and more specifically coronary artery disease presentations in women, are different than those in men. In addition, pathology and pathophysiology of the disease present significant gender differences, which leads to difficulties concerning diagnosis, treatment and outcome of the female population. The reason for this disparity is all steps for female cardiovascular disease evaluation, treatment and prevention are not well elucidated; and an area for future research. This review brings together the most recent studies published in the field of coronary artery disease in women and points out new directions for future investigation on some of the important issues.  相似文献   
906.
1,3-Butadiene is a known carcinogen and mutagen that acts through a variety of metabolic intermediates that react with DNA, forming stable and unstable lesions on dG, dA, dC, and dT. The N3 2'-deoxyuridine adducts are a highly stable, stereoisomeric mixture of adducts derived from the reaction of cytosine with the monoepoxide metabolite of butadiene, followed by spontaneous deamination. In this study, the phosphoramidites and subsequent oligodeoxynucleotides containing the N3 2'-deoxyuridine adducts have been constructed and characterized. Using a single-stranded shuttle vector DNA, the mutagenic potential of these adducts has been tested following replication in mammalian cells. Replication past the N3 2'-deoxyuridine adducts was found to be highly mutagenic with an overall mutation yield of approximately 97%. The major mutations that were observed were C to T transitions and C to A transversions. In vitro, these adducts posed a complete block to both the Klenow fragment of Escherichia coli polymerase I and polymerase epsilon, while these lesions significantly blocked polymerase delta. These data suggested a possible involvement of bypass polymerases in the in vivo replication of these lesions. Overall, these findings indicate that the N3 2'-deoxyuridine adducts are highly mutagenic lesions that may contribute to butadiene-mediated carcinogenesis.  相似文献   
907.
Subepithelial fibrosis is one of the characteristic features of asthmatic airways. The fibrotic response includes an increase in volume occupied by extracellular matrix (ECM) tissue, and a change in the ECM composition favouring wound type collagens, fibronectin and a number of glycoproteins and proteoglycans normally associated with development. The altered ECM is likely to be deposited by the mesenchymal cells (including (myo) fibroblasts and smooth muscle) that are increased in number in asthmatic airways. In turn, the altered asthmatic ECM is likely to influence the function of the resident airway cells, and may be directly responsible for increasing proliferation, migration, ECM synthesis, inflammatory mediator release, and survival of resident mesenchymal cells. Therefore, the deposited ECM may perpetuate the disease phenotype. The different components of the ECM bi-directionally communicate with cells through a family of transmembrane receptors called integrins. Current research has begun to characterize: 1) the particular ECM components altered in airways disease; 2) the breadth of activity of different ECM components on airway cell function; and 3) the particular integrins responsible for mediating these effects. Further understanding of the role of integrins in transmitting responses of ECM in healthy or diseased airways may lead to novel targets for anti-asthma therapy.  相似文献   
908.
This report describes the various uses of a large bladder flap for the reconstruction of the lower ureter and female urethra. It also explains the method for closing a large vesicovaginal fistula and other bladder-wall defects with an advancement flap of bladder wall. Fifteen cases are presented in which these procedures were carried out.  相似文献   
909.
910.
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