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排序方式: 共有951条查询结果,搜索用时 15 毫秒
1.
Evangelos Pavlakis Michelle Neumann Thorsten Stiewe 《International journal of molecular sciences》2020,21(24)
Tumor progression to a metastatic and ultimately lethal stage relies on a tumor-supporting microenvironment that is generated by reciprocal communication between tumor and stromal host cells. The tumor–stroma crosstalk is instructed by the genetic alterations of the tumor cells—the most frequent being mutations in the gene Tumor protein p53 (TP53) that are clinically correlated with metastasis, drug resistance and poor patient survival. The crucial mediators of tumor–stroma communication are tumor-derived extracellular vesicles (EVs), in particular exosomes, which operate both locally within the primary tumor and in distant organs, at pre-metastatic niches as the future sites of metastasis. Here, we review how wild-type and mutant p53 proteins control the secretion, size, and especially the RNA and protein cargo of tumor-derived EVs. We highlight how EVs extend the cell-autonomous tumor suppressive activity of wild-type p53 into the tumor microenvironment (TME), and how mutant p53 proteins switch EVs into oncogenic messengers that reprogram tumor–host communication within the entire organism so as to promote metastatic tumor cell dissemination. 相似文献
2.
3.
Prof. Dr.-Ing. Thorsten Spitta Dipl. Ing. Helmut Schmidpeter 《WIRTSCHAFTSINFORMATIK》2002,44(2):141-150
This paper analyses the characteristics of software houses as service providers. The tasks of internal IT-services are determined from these characteristics and a reporting system for the IT-controlling is outlined. The concept results from the analysis of one of the 25 largest German software houses. The paper concludes with a case study of the fiscal year 2000 IT-controlling report of the above-mentioned firm. 相似文献
4.
W. Nierle W. Feldheim H. G. Maier P. Schreier W. Grosch G. -W. v. Rymon Lipinski H. -P. Thier W. Feldheim W. Seibel J. Buchberger E. Schlimme G. Engel U. Sacher F. Siewek R. Frommberger R. Frommberger G. -W. v. Rymon Lipinski F. I. Schäfers F. I. Schäfers R. Matissek H. Klostermeyer F. Kiermeier H. -P. Thier M. Miller M. Miller H. Wieczorek F. Jekat W. Feldheim K. Eichner M. Petz D. Gottschalk und W. Nierle 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,185(2):134-144
5.
Michael Maiwald Hongping Li Thorsten Schnabel Kay Braun Hans Hasse 《The Journal of Supercritical Fluids》2007,43(2):267
On-line NMR spectroscopy can beneficially be applied to studies of supercritical and near-critical fluids as an alternative to optical spectroscopy. Up to now high pressure NMR experiments are predominantly accomplished using custom made NMR batch reactors. The authors present a novel high pressure cell with displacement plunger for on-line NMR experiments on compressible fluids which can be used in conjunction with commercially available SCF NMR flow probes. The on-line technique offers advantages compared to stopped flow techniques such as enhanced control of mixture composition and reaction parameters as well as the facility of engagement into the reaction. The new apparatus is used for NMR studies on hydrogen bonding of methanol in near critical and supercritical carbon dioxide up to 403 K and 35 MPa for which data on the chemical shift of the hydroxyl group and methyl group are reported and interpreted. 相似文献
6.
Bing Pan Helene Hembrooke Thorsten Joachims Lori Lorigo Geri Gay Laura Granka 《Journal of Computer-Mediated Communication》2007,12(3):801-823
An eye tracking experiment revealed that college student users have substantial trust in Google's ability to rank results by their true relevance to the query. When the participants selected a link to follow from Google's result pages, their decisions were strongly biased towards links higher in position even if the abstracts themselves were less relevant. While the participants reacted to artificially reduced retrieval quality by greater scrutiny, they failed to achieve the same success rate. This demonstrated trust in Google has implications for the search engine's tremendous potential influence on culture, society, and user traffic on the Web. 相似文献
7.
John W. Elmer Joe Wong Thorsten Ressler 《Metallurgical and Materials Transactions A》1998,29(11):2761-2773
Spatially resolved X-ray diffraction (SRXRD) is used to map the α → β → α phase transformation in the heat-affected zone (HAZ) of commercially pure titanium gas tungsten arc welds. In situ SRXRD experiments were conducted using a 180-μm-diameter X-ray beam at the Stanford Synchrotron Radiation Laboratory (SSRL)
(Stanford, CA) to probe the phases present in the HAZ of a 1.9 kW weld moving at 1.1 mm/s. Results of sequential linear X-ray
diffraction scans made perpendicular to the weld direction were combined to construct a phase transformation map around the
liquid weld pool. This map identifies six HAZ microstructural regions between the liquid weld pool and the base metal: (1)
α-Ti that is undergoing annealing and recrystallization; (2) completely recrystallized α-Ti; (3) partially transformed α-Ti, where α-Ti and β-Ti coexist; (4) single-phase β-Ti; (5) back-transformed α-Ti; and (6) recrystallized α-Ti plus back-transformed α-Ti. Although the microstructure consisted predominantly of α-Ti, both prior to and after the weld, the crystallographically textured starting material was altered during welding to produce
different α-Ti textures within the resulting HAZ. Based on the travel speed of the weld, the α → β transformation was measured to take 1.83 seconds during heating, while the β → α transformation was measured to take 0.91 seconds during cooling. The α → β transformation was characterized to be dominated by long-range diffusional growth on the leading (heating) side of the weld,
while the β → α transformation was characterized to be predominantly massive on the trailing (cooling) side of the weld, with a massive growth
rate on the order of 100 μm/s. 相似文献
8.
Wolfgang Schmid und Werner Grosch 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1986,182(5):407-412
Zusammenfassung Die Aromastoffe wurden aus Kirschsaft isoliert durch simultane Destillation/Extraktion (Extrakt I) und durch Destillation in Vakuum mit anschließender Extraktion des Destillates (Extrakt II). Die beiden Extrakte wurden entsäuert, fraktioniert und durch HRGC analysiert. Die chemischen Strukturen wurden nur von den Aromastoffen analysiert, die im Sniffing-port nach der HRGC-Trennung zu erkennen waren. Identifiziert wurden 28 Aromastoffe im Extrakt I und 18 im Extrakt II; 16 davon enthielt auch Extrakt I. Beim Abriechen der schrittweise verdünnten Extrakte im Sniffing-port wurden in beiden Extrakten dieselben sieben Verbindungen mit den höchsten Aromawerten gefunden: Benzaldehyd, Linalool, Hexanal, 2(E)-Hexanal, Phenylacetaldehyd, 2(E),6(Z)-Nonadienal und Eugenol. Extrakt I enthielt zusätzlich einen fruchtigen Aromastoff unbekannter Struktur mit hohem Aromawert.
Identification of highly aromatic volatile flavour compounds from cherries (Prunus cerasus L.)
Summary The flavour compounds were isolated from cherry juice by simultaneous distillation/extraction (extract I) and also by vacuum distillation followed by extraction of the condensate (extract II). Both extracts were freed from the acids, fractionated and then analyzed by HRGC. The chemical structures of only the flavour compounds detectable at the sniffing-port of the HRGC-effluent were determined. 28 Flavour compounds were identified in extract I; 18 in extract II of which 16 occurred also in extract I. Sniffing the stepwise diluted extracts I and II revealed the same seven compounds with the highest aroma values: benzaldehyde, linalool, hexanal, 2(E)-hexanal, phenylacetaldehyde, 2(E),6(Z)-nonadienal and eugenol. Extract I contained in addition a flavour compound of high aroma value, whose structure is unknown.相似文献
9.
Wolfgang Schmid und Werner Grosch 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1986,183(1):39-44
Zusammenfassung Sieben Aromastoffe, isoliert durch Destillation im Vakuum aus Sauer- und Süßkirschprodukten, wurden vergleichend analysiert. In den frisch gepreßten Säften aus je fünf Sorten Sauer- und Süßkirschen wurden große Konzentrationsunterschiede (gm/l) gefunden: Benzaldehyd (18–393), Linalool (0,5–1,7), Hexanal (0,3–54,7), 2(E)-Hexenal (2,4220), 2(E),6(Z)-Nonadienal (0,1–2,4), Phenylacetaldehyd (2,1–5,6) und Eugenol (1,0–22,2). Die Benzaldehydkonzentration zeigte die höchste Korrelation zur Erkennungsschwelle für den Kirschgeruch der Säfte. Bei der Herstellung von Konfitüren veränderte sich die Zusammensetzung der Aromastoffe: Benzaldehyd und Linalool nahmen um den Faktor 7 bzw. 13 zu; Hexanal, 2(E)-Hexenal sowie Phenylacetaldehyd nahmen stark ab. Der Anstieg von Benzaldehyd und Linalool, der auch bei der simultanen Destillation/Extraktion der Säfte auftrat, beruht auf einer Hydrolyse entsprechender Glykoside, die durch eine Hitzebehandlung stark beschleunigt wird.
Quantitative analysis of the volatile flavour compounds having high aroma values from sour (Prunus cerasus L.) and sweet (Prunus apium L.) cherry juices and jams
Summary The analysis results for seven of the aroma compounds obtained by vacuum distillation from sweet and sour cherry products were compared. The freshly pressed juices from 5 varieties of sour and 5 varieties of sweet cherries showed great differences in concentrations (g/1): benzaldehyde (18–393), linalool (0.5–1.7), hexanal (0.3–54.7), 2(E)-hexenal (2.4–220), 2(E),6(Z)-nonadienal (0.1–2.4), phenylacetaldehyde (2.1–5.6) and eugenol (1.0–22.2). The benzaldehyde content of the juices showed the highest correlation to the recognition threshold of the cherry aroma note. The cherry jam showed a drastic change in the aroma composition: benzaldehyde and linalool increased greatly (7 and 13-times, respectively), while hexanal, 2(E)-hexenal and phenylacetaldehyde strongly decreased. The increase in benzaldehyde and linalool, which was also observed during simultaneous distillation/extraction of the juices, is caused by the hydrolysis of the corresponding glycosides during the heat treatments.相似文献
10.
Andreas Brodehl Alexey Meshkov Roman Myasnikov Anna Kiseleva Olga Kulikova Brbel Klauke Evgeniia Sotnikova Caroline Stanasiuk Mikhail Divashuk Greta Marie Pohl Maria Kudryavtseva Karin Klingel Brenda Gerull Anastasia Zharikova Jan Gummert Sergey Koretskiy Stephan Schubert Elena Mershina Anna Grtner Polina Pilus Kai Thorsten Laser Valentin Sinitsyn Sergey Boytsov Oxana Drapkina Hendrik Milting 《International journal of molecular sciences》2021,22(7)
About 50% of patients with arrhythmogenic cardiomyopathy (ACM) carry a pathogenic or likely pathogenic mutation in the desmosomal genes. However, there is a significant number of patients without positive familial anamnesis. Therefore, the molecular reasons for ACM in these patients are frequently unknown and a genetic contribution might be underestimated. Here, we used a next-generation sequencing (NGS) approach and in addition single nucleotide polymor-phism (SNP) arrays for the genetic analysis of two independent index patients without familial medical history. Of note, this genetic strategy revealed a homozygous splice site mutation (DSG2–c.378+1G>T) in the first patient and a nonsense mutation (DSG2–p.L772X) in combination with a large deletion in DSG2 in the second one. In conclusion, a recessive inheritance pattern is likely for both cases, which might contribute to the hidden medical history in both families. This is the first report about these novel loss-of-function mutations in DSG2 that have not been previously identi-fied. Therefore, we suggest performing deep genetic analyses using NGS in combination with SNP arrays also for ACM index patients without obvious familial medical history. In the future, this finding might has relevance for the genetic counseling of similar cases. 相似文献