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Brain Imaging and Behavior - Oxytocin is both a hormone and a neurotransmitter and has been originally recognized for its role in childbirth and lactation. Later, it became widely known as a...  相似文献   
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PURPOSE: To analyze the effectiveness of surgery and chemotherapy with or without radiotherapy in the management of limited small cell lung cancer (LSCLC) in stages I and II. PATIENTS AND METHODS: 39 patients (median age 62 years) with LSCLC in stages pT1 or pT2 and pN0 or pN1 (stages IA-IIB) who had a tumor resection and systematic lymph node dissection were reviewed retrospectively. The median follow-up period was 29 months. 35 patients (90%) received a median of four cycles of a platinum-containing chemotherapy postoperatively. 16 patients (41%) received an adjuvant thoracic radiotherapy (TRT, median 50 Gy); 21 patients (54%) received a prophylactic cranial irradiation (PCI, median 30 Gy). RESULTS: The median overall survival for all patients was 47 months, resulting in actuarial 1-, 3-, and 5-year survival rates of 97%, 58%, and 49%, respectively. Distant metastases were found in 13 patients (33%) after a median of 16 months. Patients who received an adjuvant TRT showed a trend toward improved thoracic recurrence-free survival (p = 0.06) and improved overall survival (p = 0.07) compared to those treated with surgery and chemotherapy only. Brain metastasis-free survival (p = 0.01) and overall survival (p = 0.01) were improved significantly in patients who received a PCI. CONCLUSION: Surgical tumor resection may be considered for carefully selected patients. Adjuvant chemotherapy and PCI are recommended for all patients. Adjuvant TRT is currently used in patients with positive lymph nodes (pN1), because the probability of a subclinical involvement of the mediastinal lymphatic system appears to be increased in these patients.  相似文献   
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Re-epithelialization of cutaneous wounds is a coordinated process of proliferation and migration of keratinocytes at the wound edge. The study objective was to identify the differences in epidermal morphology, keratinocyte proliferation and matrix molecules (laminin 1, laminin 5, type IV collagen) and their specific integrin (α3, α6) expression in biopsies of meshed split thickness grafted and chronic wounds. The mean mitotic index of keratinocytes (ratio of cell cycle associated antigen Ki-67 expressing keratinocytes to basal keratinocytes) was highest in chronic wounds (38.7%) compared to acute wounds (22.25%, range 5.7% to 54%). The mean thickness of the hyper-proliferative epithelium at the wound edge of chronic wounds was 0.69 mm compared to 0.15 mm at the wound margin of split thickness grafted wounds. Both chronic wounds and skin grafted wounds exhibited strong laminin 5 immunoreactivity at the basal side of the epithelium, which extended under the most forward keratinocytes. Laminin 1 and type IV collagen immunoreactivity did not extend to the wound margin in either skin grafted or chronic wounds. In both transplanted skin and chronic wounds, the integrin sub-units α3 and α6 exhibited a strong pericellular immunoreactivity on the leading keratinocytes of the wound margin. Our data demonstrates that the proliferation of keratinocytes and the expression of associated integrins are not impaired in chronic wounds. Presented at the 33rd Congress of the Association of German Plastic Surgeons, Germany, 18–21 September, 2002.  相似文献   
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BACKGROUND: Dyslipidaemia, inflammation and oxidative stress are prominent risk factors that potentially cause vascular disease in haemodialysis patients. Dialysis modalities affect uraemic dyslipidaemia, possibly by modifying oxidative stress, but the effects of dialyser flux and membrane material on atherogenic remnant particles and oxidized low-density lipoproteins (LDL) are unknown. METHODS: We performed a randomized crossover study in 36 patients on haemodialysis to analyse the effect of dialyser flux and membrane material on plasma lipids, apolipoproteins and markers of inflammation and oxidative stress. Stable patients on low-flux dialysis with polysulphone for >/=6 weeks were assigned to high-flux polysulphone or high-flux modified cellulose with similar dialyser surface area and permeability characteristics and crossed over twice every 6 weeks. RESULTS: Thirty patients completed the study per protocol. Treatments with high-flux polysulphone and modified cellulose lowered serum triglyceride (by 20% and 10%, respectively; P<0.05) and remnant-like particle cholesterol by 32% (P<0.001) and 11% (NS) after the first 6 weeks of treatment. Oxidized LDL decreased significantly with high-flux polysulphone, but not with modified cellulose. Apolipoproteins CII and CIII were reduced, whereas the ratio CII/CIII was increased (all P<0.05). Acute-phase proteins and LDL and high-density lipoprotein cholesterol remained unaffected. CONCLUSIONS: This randomized crossover study demonstrates a potent effect of high-flux haemodialysis on uraemic dyslipidaemia. Polysulphone membrane material showed superiority on oxidatively modified LDL, an indicator of oxidative stress in haemodialysis patients.  相似文献   
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Quantification of oxidative DNA modifications in mitochondria   总被引:2,自引:0,他引:2  
Specific repair endonucleases were used to quantify oxidativemodifications in mitochondrial DNA (mtDNA) from rat liver andfrom porcine liver and kidney by means of a relaxation assay.In rat liver mitochondria the number of modifications sensitiveto formamidopyrimidine-DNA glycosylase (FPG protein), whichinclude 8-hydroxyguanine (8-oxo-7, 8-dihydro-guanine) residues,was only 0.8±0.2 per 105 base pairs (bp). Even lowervalues were observed in porcine kidney (0.5±0.3 per 105bp) and liver (0.4±0.2 per 105 bp). The numbers of sitesof base loss (AP sites) sensitive to T4 endonuclease V and of5,6-dihydropyrimidines sensitive to endonuclease III were lessthan 0.2 per 105 bp in all cases. The data provide evidencethat the steady-state levels of oxidative mtDNA modificationsare low under physiological conditions, either because reactiveoxygen species generated in the mitochondria are instantly inactivatedor because of efficient DNA repair processes inside mitochondria.  相似文献   
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OBJECTIVE: The present study presents a novel approach to averaging of event-related potentials (ERPs). Acknowledging latency variability of late ERP components as related to performance fluctuations across trials should improve the assessment of late portions of the ERP. METHODS: Prior to the averaging procedure stimulus-to-response epochs in the electroencephalogram (EEG) were expanded/compressed in time to match mean RT in a certain condition and participant. By means of several mathematical functions RT variability was differentially distributed over late vs. early portions of the ERP. Data from 20 participants from two conditions of an identity-based priming task were analyzed using traditional stimulus- and response-locked averaging, as well as four different RT-corrected averaging procedures. RESULTS: Area under the curve as an index of precision of LPC assessment was reliably enhanced for certain RT-corrected procedures relative to traditional ERP averaging. Moreover, a priming effect on amplitude of a distinct LPC subcomponent which could not be confirmed with traditional stimulus-locked averaging was reliably born out using a cubic RT-correction procedure. CONCLUSIONS: RT-corrected ERP averaging can outperform traditional ERP averaging in the assessment of late portions of the ERP, and experimental effects upon. SIGNIFICANCE: Cognitive ERP researchers may take advantage of the improved capability of RT-corrected averaging to establish experimental effects on amplitudes in the late ERP range.  相似文献   
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Summary This study examines the relationship between various aspects of social relations and the prevalence of smoking, using data from the first MONICA Survey, Augsburg, FRG, 1984/85. Study population of the survey was a two-stage cluster sample of 5312 men and women aged 25 to 64. The response was 79.4%. The measurement of social relations included a modified form of the Syme/Berkman social network scale, as used in the Alameda County Study. Analyses were carried out separately for the total four-level social network index in relation to smoking, and for specific components of that index (marital status, contacts with friends and relatives, activities in informal groups). The results showed for both men and women, that there was a significant association between the social network index and the prevalence of smoking: the more social ties and contacts, the lower the percentage of smokers. The results from multiple logistic regression analyses indicated an effect of social relations on smoking, that is at least partly independent of age, gender and educational level. In general, the findings may contribute to a better understanding of risk groups, and the possible pathways leading from social relations to health and disease.
Soziale Beziehungen und Rauchverhalten. Ergebnisse der ersten MONICA-Augsburg- Querschnittsstudie
Zusammenfassung Mit Daten der ersten MONICA-Querschnittsstudie Augsburg, 1984/ 85, wurden die Zusammenhänge zwischen verschiedenen Merkmalen des «sozialen Netzwerks» und dem individuellen Rauchverhalten untersucht. Die Studienpopulation umfasste 5312 Männer und Frauen einer zweistufigen Zufallsstichprobe im Alter zwischen 25 und 64 Jahren. Die Teilnahmerate betrug 79,4%. Die sozialen Beziehungen wurden in einem Fragebogen zum Selbstausfüllen mit Hilfe eines «Sozialen Netzwerk Indexes» (SNI) erfasst, der sowohl den Familienstand, die Kontakte zu Verwandten und engen Freunden als auch Aktivitäten in Gruppen und Vereinen beinhaltete. Die Ergebnisse zeigten für Männer und Frauen statistisch signifikante Zusammenhänge zwischen den Gesamtscores des SNI und der Prävalenz des Rauchens: Je mehr soziale Beziehungen und Kontakte, desto geringer war der Anteil Raucher. Die Analysen einzelner Komponenten des SNI ergaben: Es fanden sich keine konsistenten Zusammenhänge zwischen den Aktivitäten in Freizeitclubs und dem Rauchverhalten, jedoch zwischen familiären Beziehungen, Kontakten zu engen Freunden oder Verwandten und der Häufigkeit des Rauchens. Besonders auffallend war der hohe Anteil Raucher bei den geschiedenen oder getrenntlebenden Männern. 70% von ihnen waren Raucher im Vergleich zu 37% der verheirateten Männer. Die entsprechenden Anteile bei den Frauen waren 42% bzw. 22%. Die Ergebnisse der multiplen logistischen Regressionen zeigten einen Effekt der interpersonellen Beziehungen auf das Rauchverhalten, der unabhängig war von den Faktoren Alter, Geschlecht, Bildungsstand und (bei Frauen) von der Erwerbstätigkeit. Die Resultate könnten zu einer besseren Erklärung und Identifizierung von Risiko-Gruppen und damit zu einer erfolgreicheren Bekämpfung des Rauchens beitragen.

Rapports sociaux et consommation de la cigarette
Résumé Les relations entre les différentes propriétés du «réseau social» et les habitudes individuelles en ce qui concerne la consommation de la cigarette ont été examinées à l'aide des données d'une première étude transversale, faite en région augsbourgeoise, dans le cadre du projet MONICA. L'échantillon aléatoire, divisé en deux étapes, comportait une population de 5312 hommes et femmes âgés de 25 à 64 ans. 79,4% des personnes interrogées participaient à l'enquête. Le recensement des rapports sociaux s'effectuait au moyen d'un questionnaire individuel à «l'Index du Réseau Social» (IRS) qui englobait aussi bien les données sur l'état civil que les sujets relatifs aux contacts sociaux et familiaux. Les résultats ont montré qu'il y avait une correspondance significative entre les valeurs totales du IRS et la prévalence de la consommation de la cigarette. Plus une personne avait de contacts sociaux, moins elle fumait de cigarettes. L'analyse des divers composants du IRS révèle un manque de relations cohérentes entre les activités dans les clubs de loisirs et la consommation de la cigarette. Cependant, la correspondance entre les rapports de famille, les contacts avec amis et parents et la fréquence de la consommation du tabac s'avérait révélatrice. Particulièrement frappant était le taux élevé de fumeurs chez les hommes divorcés ou vivant séparés. 70% d'entre eux étaient fumeurs par rapport à 37% des hommes mariés. Le taux correspondant chez les femmes était de 42% resp. 22%. Les résultats de la régression logistique multiple signalaient un effet des relations interpersonnelles sur la consommation de la cigarette, un effet qui était indépendant des facteurs tels que l'âge, le sexe, le niveau d'instruction et (chez les femmes) des activités professionnelles. Ces résultats pourraient contribuer à une meilleure identification et caractérisation des groupes à risque, et par la suite à combattre d'une manière plus efficace la consommation de la cigarette.
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