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991.
The aim of the study was to meet the opinions of NHs' residents about the meals quality and nutrition system, with special consideration of meal ambience in canteens (appearance, atmosphere, etc.). Besides, other information about residents was collected: their self-perceived health status, psychical condition, physical activity, appetite and nutritional habits. Most of the subjects were single women, mainly with medium/technical education level, living in NHs over 3 years. Most of the NHs' residents evaluated their health status as average or bad, independently of the age or gender. Every second person indicated that health, loneliness and the feeling of isolation in their homes were the main reasons for coming to NH. Every third person still felt the loneliness or depression after staying in NH. The physical and intellectual activity of elderly depended on self-perceived health status. Over half of the subjects assessed their appetite as good, and said that their body mass was stable during staying in NH. The statistically significant relationship was found between the self-evaluated weight change and both age and gender. Additionally, the relationship was observed between psychical condition of residents and their appetite as also between the psychical condition and weight change during living in NH. The majority of the subjects (85%) said that they liked the canteen appearance, and they did not want to change anything in it. More women than men thought that canteens were spacious, clean and furnished with good taste, and those differences were significant. Part of studied population (25%) had some reservations about the atmosphere in canteen during the meals, mostly because of too much noise. In the opinions of most of the residents (over 80%) the nutrition organisation in NHs was good. Over half of the subjects assessed the meals quality in NHs also as good. Only some comments were about insufficient quantities of fruits and vegetables and meal monotony.  相似文献   
992.
In this study, the authors examined the effects of alcohol, tobacco, and drug use on plasma testosterone and seminal parameters (in accordance with the World Health Organization's standards) in healthy Argentine medical students (n = 34). Some alterations in seminal parameters were detected in 19 (56%) subjects. Alcohol and tobacco use were correlated significantly, p = 0.005; subjects who used these substances exhibited a nonsignificant reduction in sperm concentration, motility, viability, and normal morphology. There was a significant decrease in sperm motility among students who used moderate amounts of aspirin (i.e., > or = 500 mg/wk). The authors concluded that alcohol, tobacco, and aspirin use could have had detrimental effects on seminal parameters and that men who wish to procreate should be warned of such effects. Doses, exposure time, and interactions with other variables deserve additional study.  相似文献   
993.
The aim of this study was to investigate the health risks due to combustor emissions in the manufacturing of Portland cement for the population living in the neighborhood of a cement kiln in Catalonia, Spain. Pollutants emitted to the atmosphere in the course of cement production were modeled. The ISC3-ST model was applied to estimate air dispersion of the contaminants emitted by the cement plant. Air concentrations of NO(2), SO(2), PM(10), metals, and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), as well as the potential exposure in the vicinity of the facility, were assessed via models based on US EPA guidance documents. PCDD/F and metal concentrations were also modeled for soil and vegetation. Based on these concentrations, the levels of human exposure were calculated. Individual cancer and noncancer risks for the emissions of the cement kiln were assessed. Health effects due to NO(2), SO(2), and PM(10) emissions were also evaluated. Risk assessment was performed as a deterministic analysis. The main individual risk in the population was evaluated in a central-tendency and a high-end approach. The results show that the incremental individual risk due to emissions of the cement plant is very low not only with regard to health effects, but also in relation to toxicological and cancer risks produced by pollutants such as metals and PCDD/Fs emitted by the cement kiln.  相似文献   
994.
The human P2Y(13) receptor is a new receptor characterized by coupling to Gi, responsiveness to adenine di-phospho-nucleotides and blockade by the P2Y antagonist AR-C69931MX. The mouse P2Y(13) ortholog has also been reported. Here we report, for the first time, the cloning of rat P2Y(13) receptor, its pharmacological analysis and tissue distribution. Rat P2Y(13) is 79% and 87% identical to human and mouse P2Y(13) receptors, respectively. Expression of rP2Y(13) receptor in 1321N1 cells induced the appearance of responses to the typical P2Y(13) receptor agonists ADP and 2MeSADP, as detected by stimulation of [(35)S]GTPgammaS binding. Agonist activities were higher in cells transfected with rP2Y(13) receptor in the presence of the Galpha(16) subunit; in all cases agonist effects were abolished by pertussis toxin pre-treatment. At variance from both human and mouse receptors, ADP was more potent than 2MeSADP. Other nucleotides and sugar-nucleotides were ineffective. Both in the absence and presence of Galpha(16), activation of rP2Y(13) receptor by ADP and 2MeSADP was completely inhibited by nM concentrations of AR-C69931MX. In contrast, no inhibition of rP2Y(13) receptor was induced by the selective P2Y(1) receptor antagonist MRS2179. rP2Y(13) receptor showed highest expression levels in spleen, followed by liver and brain (with particularly high levels in cortex and striatum as reported in man), suggesting important roles in the nervous and immune systems. Expression levels comparable to those of the other cloned P2Y receptors were found in primary rat astrocytes, indicating a possible role in reactive astrogliosis. Hence, rat P2Y(13) receptor displays several similarities but also interesting differences with its human and mouse orthologs, that will have to be taken into account when characterizing the pathophysiological roles of this receptor in the rat animal models.  相似文献   
995.
Red wine polyphenolic compounds (RWPCs) are potent inducers of endothelium-dependent relaxations of coronary arteries, which involve both nitric oxide and endothelium-derived hyperpolarizing factor (EDHF). The EDHF-mediated relaxation to RWPCs is critically dependent on the formation of reactive oxygen species by a flavin-dependent enzyme. The aim of the present study was to determine the role of redox-sensitive protein kinases including p38 MAPK, ERK1/2 and PI3-kinase/Akt in RWPCs-induced EDHF-mediated relaxation. Porcine coronary artery rings were suspended in organ chambers for measurement of changes in isometric tension. Confluent cultures of porcine coronary artery endothelial cells were used to determine the phosphorylation level of p38 MAPK, ERK1/2 and Akt by Western blot analysis. All experiments were performed in the presence of indomethacin and Nomega-nitro-L-arginine. RWPCs caused pronounced endothelium-dependent relaxations, which were significantly reduced by wortmannin and LY294002, two inhibitors of PI3-kinase, and not affected by PD98059 (an inhibitor of ERK1/2 kinase kinase) and SB203580 (an inhibitor of p38 MAPK). In contrast, wortmannin did not affect relaxations to bradykinin or levcromakalim. RWPCs elicited within minutes a sustained and concentration-dependent phosphorylation of p38 MAPK, ERK1/2 and Akt in endothelial cells. The phosphorylation of Akt in response to RWPCs was abolished by wortmannin and LY294002, and by the membrane-permeant analogue of superoxide dismutase Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin. The present findings demonstrate that RWPCs cause EDHF-mediated relaxations of coronary arteries; these responses are critically dependent on the redox-sensitive activation of the PI3-kinase/Akt pathway in endothelial cells.  相似文献   
996.
997.
In the search for strains producing antifungal compounds, a new tetraene macrolide CE-108 (3) has been isolated from culture broth of Streptomyces diastaticus 108. In addition, the strain also produces the previously described tetraene rimocidin (1) and also the aromatic polyketide oxytetracycline. Both tetraene compounds, structurally related, are produced in a ratio between 25 to 35% (CE-108 compared to rimocidin), although it can be inverted toward CE-108 production by changing the composition of the fermentation medium. This paper deals with the characterization of the producer strain, fermentation, purification, structure determination and biological properties of the new macrolide tetraene CE-108.  相似文献   
998.
With the aim of studying the contribution of the beta II turn conformation at the side chain of didemnins to the bioactive conformation responsible for their antitumoral activity, conformationally restricted analogues of aplidine and tamandarin A, where the side chain dipeptide Pro8-N-Me-d-Leu7 is replaced with the spirolactam beta II turn mimetic (5R)-7-[(1R)-1-carbonyl-3-methylbutyl]-6-oxo-1,7-diazaspiro[4.4]nonane, were prepared. Additionally, restricted analogues, where the aplidine (pyruvyl9) or tamandarin A [(S)-Lac9] acyl groups are replaced with the isobutyryl, Boc, and 2-methylacryloyl groups, were also prepared. These structural modifications were detrimental to cytotoxic activity, leading to a decrease of 1-2 orders of magnitude with respect to that exhibited by aplidine and tamandarin A. The conformational analysis of one of these spirolactam aplidine analogues, by NMR and molecular modeling methods, showed that the conformational restriction caused by the spirolactam does not produce significant changes in the overall conformation of aplidine, apart from preferentially stabilizing the trans rotamer at the pyruvyl9-spirolactam amide bond, whereas in aplidine both cis and trans rotamers at the pyruvyl9-Pro8 amide bond are more or less equally stabilized. These results seem to indicate a preference for the cis form at that amide bond in the bioactive conformation of aplidine. The significant influence of this cis/trans isomerism upon the cytotoxicity suggests a possible participation of a peptidylprolyl cis/trans isomerase in the mechanism of action of aplidine.  相似文献   
999.
1000.
Effects of enoxaparin on histomorphometric parameters of bones in rats   总被引:1,自引:0,他引:1  
Enoxaparin sodium is a low-molecular-weight heparin. It is not clear whether the risk of development of osteoporosis after administration of low-molecular-weight heparins is lower than after administration of standard heparin. The aim of the present study was to investigate the effects of enoxaparin on histomorphometric parameters of bones in female Wistar rats (13-15 weeks old at the beginning of the experiment). Enoxaparin was administered at doses of 1000 anti-Xa IU/kg sc daily or 2000 anti-Xa IU/kg sc daily for 4 weeks. Bone mass, mineral and calcium content (in the tibia, femur and L-4 vertebra), length and diameter in the tibia and femur, and histomorphometric parameters of the tibia (periosteal and endosteal transverse growth, width of periosteal and endosteal osteoid, area of the transverse cross-section of the cortical bone in the diaphysis and area of the transverse cross-section of the marrow cavity) and the femur (width of epiphyseal and metaphyseal trabeculae, width of epiphyseal cartilage) were examined. Enoxaparin, administered at doses of 1000 anti-Xa IU/kg sc daily or 2000 anti-Xa IU/kg sc daily for 28 days, induced osteopenic changes in the rat skeletal system. The changes observed in bone histomorphometric parameters indicate that enoxaparin caused the inhibition of bone formation and intensification of bone resorption.  相似文献   
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