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排序方式: 共有345条查询结果,搜索用时 22 毫秒
1.
Reinhold Munker Oliver Stötzer Mareike Darsow Susanne Classen Annette Lebeau Wolfgang Wilmanns 《Cancer immunology, immunotherapy : CII》1996,42(3):200-201
Mutated human p53 may give rise to the formation of autoantibodies and may be a marker for a worse prognosis. We speculated
that ascites or pleural effusions may enhance the formation of such autoantibodies in cancer patients and, therefore, we measured
the presence of autoantibodies in the ascites or pleural effusion of 40 patients with advanced malignancies. As controls,
p53 autoantibodies were measured in 15 patients with effusions who did not have a malignancy. Using a specific enzyme-linked
immunosorbent assay, p53 autoantibodies could only be detected in the effusions of 5/40 patients (12.5%) with known malignancies.
The formation of autoantibodies did not correlate with the presence or absence of tumor cells in the effusion. The effusions
of the patients without tumor were all negative for p53 autoantibodies. Our study shows that malignant or reactive effusions
do not stimulate the local or systemic production of autoantibodies against p53.
Received: 14 November 1995 / Accepted: 8 February 1996 相似文献
2.
Franziska Lauer Katharina Prost Renate Gerlach Stefan P?tzold Mareike Wolf Sarah Urmersbach Eva Lehndorff Eileen Eckmeier Wulf Amelung 《PloS one》2014,9(9)
Neolithic and Bronze Age topsoil relicts revealed enhanced extractable phosphorus (P) and plant available inorganic P fractions, thus raising the question whether there was targeted soil amelioration in prehistoric times. This study aimed (i) at assessing the overall nutrient status and the soil organic matter content of these arable topsoil relicts, and (ii) at tracing ancient soil fertilizing practices by respective stable isotope and biomarker analyses. Prehistoric arable topsoils were preserved in archaeological pit fillings, whereas adjacent subsoils served as controls. One Early Weichselian humic zone represented the soil status before the introduction of agriculture. Recent topsoils served as an additional reference. The applied multi-proxy approach comprised total P and micronutrient contents, stable N isotope ratios, amino acid, steroid, and black carbon analyses as well as soil color measurements. Total contents of P and selected micronutrients (I, Cu, Mn, Mo, Se, Zn) of the arable soil relicts were above the limits for which nutrient deficiencies could be assumed. All pit fillings exhibited elevated δ15N values close to those of recent topsoils (δ15N>6 to 7‰), giving first hints for prehistoric organic N-input. Ancient legume cultivation as a potential source for N input could not be verified by means of amino acid analysis. In contrast, bile acids as markers for faecal input exhibited larger concentrations in the pit fillings compared with the reference and control soils indicating faeces (i.e. manure) input to Neolithic arable topsoils. Also black carbon contents were elevated, amounting up to 38% of soil organic carbon, therewith explaining the dark soil color in the pit fillings and pointing to inputs of burned biomass. The combination of different geochemical analyses revealed a sufficient nutrient status of prehistoric arable soils, as well as signs of amelioration (inputs of organic material like charcoal and faeces-containing manure). 相似文献
3.
Nicolai Kallscheuer Patrick Rast Mareike Jogler Sandra Wiegand Timo Kohn Christian Boedeker Olga Jeske Anja Heuer Christian Quast Frank Oliver Glöckner Manfred Rohde Christian Jogler 《Environmental microbiology》2021,23(3):1379-1396
Waterbodies such as lakes and ponds are fragile environments affected by human influences. Suitable conditions can result in massive growth of phototrophs, commonly referred to as phytoplankton blooms. Such events benefit heterotrophic bacteria able to use compounds secreted by phototrophs or their biomass as major nutrient source. One example of such bacteria are Planctomycetes, which are abundant on the surfaces of marine macroscopic phototrophs; however, less data are available on their ecological roles in limnic environments. In this study, we followed a cultivation-independent deep sequencing approach to study the bacterial community composition during a cyanobacterial bloom event in a municipal duck pond. In addition to cyanobacteria, which caused the bloom event, members of the phylum Planctomycetes were significantly enriched in the cyanobacteria-attached fraction compared to the free-living fraction. Separate datasets based on isolated DNA and RNA point towards considerable differences in the abundance and activity of planctomycetal families, indicating different activity peaks of these families during the cyanobacterial bloom. Motivated by the finding that the sampling location harbours untapped bacterial diversity, we included a complementary cultivation-dependent approach and isolated and characterized three novel limnic strains belonging to the phylum Planctomycetes. 相似文献
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Ilaria Guerini Nicola J Geisler Hengyao Niu Mareike Herzog Israel Salguero Bernardo Ochoa‐Montaño Emmanuelle Viré Patrick Sung David J Adams Thomas M Keane Stephen P Jackson 《The EMBO journal》2015,34(11):1509-1522
DNA double-strand break (DSB) repair by homologous recombination (HR) requires 3′ single-stranded DNA (ssDNA) generation by 5′ DNA-end resection. During meiosis, yeast Sae2 cooperates with the nuclease Mre11 to remove covalently bound Spo11 from DSB termini, allowing resection and HR to ensue. Mitotic roles of Sae2 and Mre11 nuclease have remained enigmatic, however, since cells lacking these display modest resection defects but marked DNA damage hypersensitivities. By combining classic genetic suppressor screening with high-throughput DNA sequencing, we identify Mre11 mutations that strongly suppress DNA damage sensitivities of sae2Δ cells. By assessing the impacts of these mutations at the cellular, biochemical and structural levels, we propose that, in addition to promoting resection, a crucial role for Sae2 and Mre11 nuclease activity in mitotic DSB repair is to facilitate the removal of Mre11 from ssDNA associated with DSB ends. Thus, without Sae2 or Mre11 nuclease activity, Mre11 bound to partly processed DSBs impairs strand invasion and HR. 相似文献
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Arash Mehdiani Anatol Maier Antonio Pinto Mareike Barth Payam Akhyari Artur Lichtenberg 《Journal of visualized experiments : JoVE》2015,(95)
Although the biological importance of exosomes has recently gained an increasing amount of scientific and clinical attention, much is still unknown about their complex pathways, their bioavailability and their diverse functions in health and disease. Current work focuses on the presence and the behavior of exosomes (in vitro as well as in vivo) in the context of different human disorders, especially in the fields of oncology, gynecology and cardiology.Unfortunately, neither a consensus regarding a gold standard for exosome isolation exists, nor is there an agreement on such a method for their quantitative analysis. As there are many methods for the purification of exosomes and also many possibilities for their quantitative and qualitative analysis, it is difficult to determine a combination of methods for the ideal approach. Here, we demonstrate nanoparticle tracking analysis (NTA), a semi-automated method for the characterization of exosomes after isolation from human plasma by ultracentrifugation. The presented results show that this approach for isolation, as well as the determination of the average number and size of exosomes, delivers reproducible and valid data, as confirmed by other methods, such as scanning electron microscopy (SEM). 相似文献
9.
Philippe Fuchs Nils Rugen Chris Carrie Marlene Elssser Iris Finkemeier Jonas Giese Tatjana M. Hildebrandt Kristina Kühn Veronica G. Maurino Cristina Ruberti Mareike Schallenberg‐Rüdinger Janina Steinbeck Hans‐Peter Braun Holger Eubel Etienne H. Meyer Stefanie J. Müller‐Schüssele Markus Schwarzlnder 《The Plant journal : for cell and molecular biology》2020,101(2):420-441
10.
Anna Juras Edvard Ehler Maciej Chyleński Łukasz Pospieszny Anna Elżbieta Spinek Helena Malmström Maja Krzewińska Krzysztof Szostek Wojciech Pasterkiewicz Marek Florek Stanisław Wilk Barbara Mnich Janusz Kruk Marzena Szmyt Sławomir Kozieł Anders Götherström Mattias Jakobsson Miroslawa Dabert 《American journal of physical anthropology》2021,176(2):223-236