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61.
Effect of titanium surface texture on the cell-biomaterial interface.   总被引:1,自引:0,他引:1  
To improve the in vivo performance of engineered implants, this study examines the independent effects of surface chemistry and topography on fibroblast morphology and density in vitro. Titanium (Ti) was sputter-coated onto smooth and microtextured polyethylene terephthalate (PET). Test specimens were evaluated in 24-h, fibroblast cultures and assessed with scanning electron microscopy (SEM) for cellular morphology and density. Fibroblast density increased, as the Ti film thickness increased. The fibroblasts exhibited contact guidance on the textured test specimens. The greatest cellular density was found on the Ti-coated, textured test specimens. In conclusion, Ti and surface texture appeared to strongly influence fibroblast density and morphology as compared to PET and smooth surfaces.  相似文献   
62.
Summary The relationship between poverty and several health-related characteristics in West Germany was investigated. Data were derived from the National and Regional Health Surveys conducted in West Germany from 1984 to 1992. 25544 males and 25719 females with German nationality aged 25–69 years were examined. Poverty was defined as a household income of 50% less than the mean for West Germany. Multiple logistic regression analysis was used to analyze the relationship between poverty and four health variables: individual health behavior, subjective assessment of health status, cardiovascular disease risk factors, and self-reported prevalence of lifetime chronic diseases. 10.2% of males and 12.8% of females were classified as being below the poverty line. For most but not all health parameters, less favourable results were found for the segment of the population with a household income below the poverty line. The most striking poverty-related differences were observed for lack of regular sport activities, subjective health satisfaction, obesity and myocardial infarction/stroke. Significantly lower prevalence rates for study subjects below the poverty line were observed for hypercholesterolemia in females only. Allergic disorders were the only chronic diseases reported significantly less often in males and females below the poverty line. Poverty has strong effects on individual health status and the prevalence of chronic diseases. Due to the rising unemployment rates in Germany in the last years it is very likely that the strong negative consequences of poverty for health are increasing.
Zusammenfassung Es wird untersucht, welche Zusammenhänge zwischen Armut und verschiedenen gesundheitsbezogenen Merkmalen bestehen. Datenbasis sind die nationalen und regionalen Gesundheitssurveys, die in den Jahren 1984 bis 1992 in Westdeutschland durchgeführt wurden. 25544 Männer und 25719 Frauen mit deutscher Nationalität im Alter von 25 bis 69 Jahren wurden einbezogen. Armut wurde definiert als ein Haushaltseinkommen, das um 50% niedriger ist als das mittlere Einkommen in Westdeutschland. Die statistische Auswertung erfolgte mittels multipler logischer Regressionsanalyse, 10,2% der Männer und 12,8% der Frauen hatten ein Haushaltseinkommen unterhalb der Armutsgrenze. Die ausgeprägtesten armutsbezogenen Unterschiede wurden beobachtet für den Mangel an körperlicher Bewegung, die subjektive Gesundheitszufriedenheit, das starke. Übergewicht und die kardiovaskulären Krankheiten. Signifikant niedrigere Prävalenzen für Personen mit Einkommen unterhalb der Armutsgrenze ergaben sich bei den Frauen für den Risikofaktor Hypercholesterinämie. Allergien waren die einzige chronische Krankheit, die bei beiden Geschlechtern signifikant seltener in der von Armut betroffenen Bevölkerungsgruppe berichtet wurde. Vor dem Hintergrund der in den letzten Jahren stark angestiegenen Arbeitslosigkeit in Deutschland ist zu befürchten, dass die negativen Konsequenzen der Armut für die gesundheitliche Lage deutlich zugenommen haben.

Résumé Les rapports entre pauvreté et differents indices sanitaires ont été examinés. Les donnees proviennent des surveys de santé nationales et régionales, réalisées en Allemagne de l'Ouest durant les années 1984 à 1992. 25719 femmes et 25544 hommes de nationalité allemande entre 25 et 69 ans ont paticipé. Le seuil de pauvreté a été fixé à un revenu égal a 50% du revenu moyen en Allemagne de l'Ouest. On a analysé les indices sanitaires suivants: le comportement sanitaire individuell, l'auto-estimation de sa santé, les facteurs de risque cardio-vasculaires et la prévalence des maladies chroniques. L'analyse statistique a été réalisée par regression logique multiple. 12,8% des femmes et 10,2% des hommes avaient un revenu inferieur au seuil de pauvreté. Pour la majorité des indices sanitaires on a trouvé des résultats défavorables pour la groupe ayant un revenu au dessous du seuil de pauvreté. Le manque de mouvement, l'auto-estimation de sa santé, l'excés de poids et les maladies cardio-vasculaires sont les indices quid diffèrent, relatif à la pauvreté, le plus. Les femmes ayant un revenu au-dessous du seuil de pauvreté ont des pourcentages de prévalence inférieurs significatifs pour le facteur de risque hypercholestérolémie. Les allergies sont les seules maladies qui existent significativement moins souvent chez les deux sexes de la groupe des pauvres. En résumé, la pauvreté présente un désavantage pour la santé individuelle et la prévalence des maladies chroniques. Sachant que le taux de chômage s'est aggravé pendant les dernières années, il est à craindre que les effets négatifs de la pauvreté sur la situation sanitaire ont nettement augmenté.
  相似文献   
63.
A novel technique for the selection of mutated DNA sequences,termed mismatch cleavage-polymerase chain reaction (MC-PCR),is proposed. The method is based on hybridizing genomic DNAwith a suitable probe, several 100 bp long. Mutated DNA sequenceswill form mismatched heteroduplexes which are cleaved by usingresolvases. Cleaved heteroduplexes are detected by ligationto an oligonucleotide adaptor and then amplified by using PCR.If practical, this technique would have considerable advantagesover the restriction site mutation (RSM) method. Failure toachieve cleavage efficiencies of close to 100% will not compromisesuccess. This is because positive signals (PCR amplification)arise from cleaved mutated sites and not, as in RSM, from DNAsequences resistant to cleavage by restriction endonucleases.Furthermore, the mutational target is much larger than in RSM.It would be possible to screen stretches of DNA several 100bp in length for mutations. Any mutation, independent of itslocation, could be identified. The usefulness of MC-PCR forthe genotypic selection of mutants will depend on the effectivenesswith which a small number of mismatched heteroduplexes can berecognized, cleaved and ligated. 1To whom correspondence should be addressed  相似文献   
64.
Highly reactive metabolites, such as oxygen free radicals, initiate a cascade of inflammatory processes in thermally damaged skin, leading to enhanced tissue loss and delayed wound healing. The extent of tissue necrosis in the zone of stasis is of prognostic significance in the wound healing process. In this study, the effect of oxygen free radical removal by recombinant human-Cu/Zn-superoxide dismutase, given in three different formulations during the inflammatory postburn phase and wound repair, was examined. Recombinant human superoxide dismutase was either injected directly into the lesions, spread as enzyme-containing gel onto the burned tissue, or encapsulated into liposomes consisting of 1,2 dipalmitoy-sn-glycero-3-phosphocholine, cholesterol and stearylamine, suspended into a hydrophilic gel and administered to burned animals immediately after trauma. Controls were treated with plain gel or kept untreated. Edema formation, size of lesions, deepening of necrosis, and reepithelialization were examined. Results indicate that superoxide dismutase treatment resulted in reduced and faster recruitment of edema formation, smaller wound sizes, and minor tissue necrosis compared to the controls, thus resulting in significantly faster reepithelialization after 3 weeks. These animal studies on the efficacy of liposomal oxygen free radical scavenger showed accelerated wound healing in all parameters tested.  相似文献   
65.
66.
Andreas Thie 《Headache》1989,29(1):59-59
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67.
68.
Magnetic resonance imaging enhanced with a macromolecular contrast medium (MMCM), albumin-Gd-DTPA, was used to estimate the plasma volume in vivo in the myocardium, lung, liver, and skeletal muscle of 10 normal rats. The plasma volumes of the same tissues in a parallel group of six rats were estimated in vitro by a conventional radioisotopic technique (111In-transferrin). Plasma volumes of myocardium, lung, liver, and skeletal muscle estimated by the MR technique (μl plas. ia cc-1 of tissue) were 101,109,163, and 11.0, respectively, while plasma volumes measured by the In-transferrin radioisotope technique (mg plasma g-1 of tissue) were 78.6, 215,143, and 11-2, respectively. Assuming a ratio of densities of aerated lung to blood of 0.45 and of other tissues to blood of 1.0, correlation between the methods was excellent (R2 = 0.99) indicating that MR imaging enhanced with MMCM permits reliable in vivo estimation of tissue plasma volume in the rat.  相似文献   
69.
70.
Functional mapping of human brain activation has been accomplished at high spatial and temporal resolution (voxel size 4.9 μl, temporal increment 100 ms). The approach was based on oxygenation-sensitive long-echo time FLASH MRI sequences synchronized to multiply repeated cycles of visual stimulation in a CINE acquisition mode. This high temporal resolution revealed that stimulus-related signal intensity changes in human visual cortex display an initial latency followed by increases extending over several seconds. Furthermore, the temporal characteristics of the complete CINE MRI signal time course depended on the absolute and relative durations of activation and control periods and, for example, caused an apparent absence of a poststimulation “undershoot” phenomenon. Complementing hyperoxygenation due to rapid hemodynamic adjustments, these results suggest signal intensity modulation by enhanced oxygen consumption and concomitant deoxygenation during prolonged and/or repetitive stimulation.  相似文献   
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