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81.
Weidong He Luc Van Puyvelde Norbert De Kimpe Luc Verbruggen Kristel Anthonissen Mark Van der Flaas Jan Bosselaers Simon G Mathenge Francis P Mudida 《Phytotherapy research : PTR》2002,16(1):66-70
Bioassay-guided fractionation of the dichloromethane extracts of the roots and the bark of Zanthoxylum usambarense led to the isolation of two physiologically active compounds, i.e. canthin-6-one 1 (fungicide) and pellitorine 4 (insecticide). Together with oxychelerythrine 2, norchelerythrine 3, (+)-sesamin 5 and (+)-piperitol-3,3-dimethylallyl ether 6, they were isolated for the first time from this plant. 相似文献
82.
Thorsten Zenz Markus Kreuz Maxi Fuge Wolfram Klapper Heike Horn Annette M. Staiger Doris Winter Hanne Helfrich Jennifer Huellein Martin‐Leo Hansmann Harald Stein Alfred Feller Peter M?ller Norbert Schmitz Lorenz Trümper Markus Loeffler Reiner Siebert Andreas Rosenwald German Ott Michael Pfreundschuh Stephan Stilgenbauer for the German High‐Grade Non‐Hodgkin Lymphoma Study Group 《International journal of cancer. Journal international du cancer》2017,141(7):1381-1388
TP53 is mutated in 20–25% of aggressive B‐cell lymphoma (B‐NHL). To date, no studies have addressed the impact of TP53 mutations in prospective clinical trial cohorts. To evaluate the impact of TP53 mutation to current risk models in aggressive B‐NHL, we investigated TP53 gene mutations within the RICOVER‐60 trial. Of 1,222 elderly patients (aged 61–80 years) enrolled in the study and randomized to six or eight cycles of CHOP‐14 with or without Rituximab (NCT00052936), 265 patients were analyzed for TP53 mutations. TP53 mutations were demonstrated in 63 of 265 patients (23.8%). TP53 mutation was associated with higher LDH (65% vs. 37%; p < 0.001), higher international prognostic index‐Scores (IPI 4/5 27% vs. 12%; p = 0.025) and B‐symptoms (41% vs. 24%; p = 0.011). Patients with TP53 mutation were less likely to obtain a complete remission CR/CRu (CR unconfirmed) 61.9% (mut) vs. 79.7% (wt) (p = 0.007). TP53 mutations were associated with decreased event‐free (EFS), progression‐free (PFS) and overall survival (OS) (median observation time of 40.2 months): the 3 year EFS, PFS and OS were 42% (vs. 60%; p = 0.012), 42% (vs. 67.5%; p < 0.001) and 50% (vs. 76%; p < 0.001) for the TP53 mutation group. In a Cox proportional hazard analysis adjusting for IPI‐factors and treatment arms, TP53 mutation was shown to be an independent predictor of EFS (HR 1.5), PFS (HR 2.0) and OS (HR 2.3; p < 0.001). TP53 mutations are independent predictors of survival in untreated patients with aggressive CD20+ lymphoma. TP53 mutations should be considered for risk models in DLBCL and strategies to improve outcome for patients with mutant TP53 must be developed. 相似文献
83.
A characteristic feature of sintered stainless steel (SSS) is its porosity. Porosity results in a lower density of steel, making attractive components for producing lightweight structures and materials used in industry (e.g., the automotive industry or aerospace). Scientists also observe that porosity adversely affects steel’s properties, especially its strength properties. One of the proposals for improving the discussed properties is the use of surface treatment of sintered stainless steels, e.g., with the use of concentrated energy sources such as plasma beams or laser beams. However, this proposal is an incidental subject of research, which is not justified from the point of view of the obtained research results presented by a few research groups. In this study, the surface modification (surface treatment) of sintered stainless steel was presented. The authors proposed the use of two surface treatments in order to compare them and obtain the best results. The first treatment was the deposit of Cr3C2–NiCr coatings on SSS surfaces using the atmospheric plasma spraying (APS) method. The second treatment was to create surface layers on SSSs by laser alloying the surface with a CO2 laser. Due to high precision and ease of automation, the most common methods in surface alloying treatment are laser technologies. This research’s main aim was to analyze the microstructure and strength properties of the SSS surface layer. The research confirms that applying the Cr3C2–NiCr coating and modifying the surface layer through the laser alloying method improves the mechanical properties of SSSs. 相似文献
84.
Markus Keller Norbert Peter Cora M. Holicki Anna V. Schantz Ute Ziegler Martin Eiden Dorian D. Drge Andreas Vilcinskas Martin H. Groschup Sven Klimpel 《Viruses》2022,14(11)
Unlike farm animals, wild animals are not subject to continuous health surveillance. Individual projects designed to screen wildlife populations for specific pathogens are, therefore, also of great importance for human health. In this context, the possible formation of a reservoir for highly pathogenic zoonotic pathogens is a focus of research. Two of these pathogens that have received particular attention during the last years are the novel severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), due to its fast global spread and high impact to the human health, and, since its introduction into Germany, the flavivirus West Nile virus (WNV). Especially in combination with invasive vertebrate species (e.g., raccoons (Procyon lotor) and raccoon dogs (Nyctereutes procyonoides) in Germany), risk analysis must be done to enable health authorities to assess the potential for the establishment of new wild life reservoirs for pathogens. Therefore, samples were collected from raccoons and raccoon dogs and analyzed for the presence of SARS-CoV-2 and WNV infections in these populations. Molecular biological and serological data obtained imply that no SARS-CoV-2 nor WNV reservoir has been established in these two wild life species yet. Future investigations need to keep an eye on these invasive carnivore populations, especially since the close contact of these animals to humans, mainly in urban areas, would make animal–human transmission a challenge for human health. 相似文献
85.
Eckhard Schlemm Mrit Jensen Amy Kuceyeski Keith Jamison Thies Ingwersen Carola Mayer Alina Knigsberg Florent Boutitie Martin Ebinger Matthias Endres Jochen B. Fiebach Jens Fiehler Ivana Galinovic Robin Lemmens Keith W. Muir Norbert Nighoghossian Salvador Pedraza Josep Puig Claus Z. Simonsen Vincent Thijs Anke Wouters Christian Gerloff Gtz Thomalla Bastian Cheng 《Human brain mapping》2022,43(16):5053
The symptoms of acute ischemic stroke can be attributed to disruption of the brain network architecture. Systemic thrombolysis is an effective treatment that preserves structural connectivity in the first days after the event. Its effect on the evolution of global network organisation is, however, not well understood. We present a secondary analysis of 269 patients from the randomized WAKE‐UP trial, comparing 127 imaging‐selected patients treated with alteplase with 142 controls who received placebo. We used indirect network mapping to quantify the impact of ischemic lesions on structural brain network organisation in terms of both global parameters of segregation and integration, and local disruption of individual connections. Network damage was estimated before randomization and again 22 to 36 h after administration of either alteplase or placebo. Evolution of structural network organisation was characterised by a loss in integration and gain in segregation, and this trajectory was attenuated by the administration of alteplase. Preserved brain network organization was associated with excellent functional outcome. Furthermore, the protective effect of alteplase was spatio‐topologically nonuniform, concentrating on a subnetwork of high centrality supported in the salvageable white matter surrounding the ischemic cores. This interplay between the location of the lesion, the pathophysiology of the ischemic penumbra, and the spatial embedding of the brain network explains the observed potential of thrombolysis to attenuate topological network damage early after stroke. Our findings might, in the future, lead to new brain network‐informed imaging biomarkers and improved prognostication in ischemic stroke. 相似文献
86.
Lara Schorn Anna Sine Karin Berr Jrg Handschel Rita Depprich Norbert R. Kübler Christoph Sproll Majeed Rana Julian Lommen 《Materials》2022,15(14)
Alloplastic and xenogeneic bone grafting materials are frequently used for bone augmentation. The effect of these materials on precursor cells for bone augmentation is yet to be determined. The aim of this study was to ascertain, in vitro, how augmentation materials influence the growth rates and viability of human unrestricted somatic stem cells. The biocompatibility of two xenogeneic and one alloplastic bone graft was tested using human unrestricted somatic stem cells (USSCs). Proliferation, growth, survival and attachment of unrestricted somatic stem cells were monitored after 24 h, 48 h and 7 days. Furthermore, cell shape and morphology were evaluated by SEM. Scaffolds were assessed for their physical properties by Micro-CT imaging. USSCs showed distinct proliferation on the different carriers. Greatest proliferation was observed on the xenogeneic carriers along with improved viability of the cells. Pore sizes of the scaffolds varied significantly, with the xenogeneic materials providing greater pore sizes than the synthetic inorganic material. Unrestricted somatic stem cells in combination with a bovine collagenous bone block seem to be very compatible. A scaffold’s surface morphology, pore size and bioactive characteristics influence the proliferation, attachment and viability of USSCs. 相似文献
87.
目的 研究白子菜Gynura divaricata地上部分醋酸乙酯萃取部位的化学成分.方法 采用不同柱色谱技术进行分离纯化,结合MS和NMR数据进行结构鉴定.结果 从白子菜地上部分80%乙醇回流提取物的醋酸乙酯萃取部位中分离纯化得到14个化合物,分别鉴定为丁二酸(1)、丁二酸单甲酯(2)、丁二酸单乙酯(3)、丁二酸甲酯乙酯(4)、对羟基苯甲酸(5)、水杨酸(6)、异香草酸(7)、对香豆酸(8)、马栗树皮素(9)、槲皮素(10)、山柰酚(11)、异槲皮苷(12)、紫云英苷(13)、芦丁(14).结论 化合物1~4、6~9为首次从该植物中分离得到. 相似文献
88.
89.
Klara Knauer Anne Bach Norbert Schffeler Andreas Stengel Johanna Graf 《Current oncology (Toronto, Ont.)》2022,29(12):9593
The possibility of positive psychological changes after cancer, namely, posttraumatic growth, is a growing field of research. Identifying personality traits and coping strategies related to posttraumatic growth may help find vulnerable individuals as well as promote helpful coping strategies to help more patients make positive changes at an early stage. The aim of this systematic literature review is to provide an overview of the quantitative data on coping strategies and personality traits associated with posttraumatic growth in patients with cancer and cancer survivors as well as the methods used in included studies. A systematic literature search was conducted using five databases (PubMed, PubPsych, PsycInfo, Web of Science, and PSYNDEXplus). The 70 reports of included studies assessed posttraumatic growth using questionnaires in a sample of patients with cancer or survivors. In addition, associations with a personality trait or coping strategy had to be examined cross-sectionally or longitudinally. All 1698 articles were screened for titles and abstracts by two authors, after which disputed articles were reviewed by a third author. Afterwards, articles were screened for full texts. Most studies had a cross-sectional design and used a sample of patients with breast cancer. Coping strategies have been researched more than personality factors. The personality traits of resilience, hardiness, dispositional positive affectivity, and dispositional gratitude seem to be related to posttraumatic growth, while the Big Five personality traits (openness to experience, conscientiousness, extraversion, agreeableness, neuroticism) have been less researched and/or seem to be unrelated. The use of social support, religious coping, positive reframing, and reflection during illness as coping strategies seems to be related to posttraumatic growth. The findings can be used for the development of interventions. Future studies should investigate associations longitudinally. 相似文献
90.
Norbert Brock Hermann Druckrey Herwig Hamperl 《Journal of cancer research and clinical oncology》1940,50(6):431-456
Zusammenfassung In Nachprüfung früherer Untersuchungen vonKinosita wurden 83 Ratten bis zur Dauer von 2 Jahren mit Buttergelb gefüttert. Dabei entstand in 12 Fällen ein primärer Leberkrebs. Während aberKinosita Krebs immer schon zwischen dem 70. und 130. Fütterungstag erhielt, traten in unseren Versuchen die Krebse erst zwischen dem 360. und 600. Tag auf, und zwar nicht bei allen Tieren.Auch der Ablauf der Leberveränderungen, die dem Krebs vorausgehen, ist gegenüber den VersuchenKinositas ein anderer: Zunächst findet sich eine Kern-und Zellschädigung, die von Gangwucherungen in denGlissonschen Scheiden gefolgt ist. Diese nehmen immer mehr überhand, werden gelegentlich cystisch, während das ursprüngliche Lebergewebe mehr und mehr zugrunde geht. Dann entstehen hepatocelluläre Adenome und schließlich Krebs, als dessen Ausgangspunkt, nach seiner Bauart zu urteilen, die Leberzellen angesehen werden müssen (hepatocellulärer Krebs).Die Kostform (Semmel-oder Reisfütterung) oder das Lebensalter der Tiere hatten keinen entscheidenden Einfluß auf den Ablauf der Leberveränderungen.Schließlich wird auf die theoretische und praktische Bedeutung der Feststellung hingewiesen, daß die Schädigung des Zellkerns die erste gestaltlich faßbare Besonderheit in der Reihe der Veränderungen ist, die zum Krebs führen.Mit 9 Textabbildungen.Die Arbeiten wurden von der Deutschen Forschungsgemeinschaft wesentlich gefördert. 相似文献