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191.
Zusammenfassung Intraperitonale Verabreichung von 3-Hydroxy-3-Methylglutarsäure setzt bei normalen Ratten den Serumspiegel von Cholesterin, Cholesterinestern, Esterfettsäuren und Triglyceriden signifikant herab. Bei einer cholesterinreichen Diät werden die Konzentrationen von Cholesterin und seinen Estern, bei hyperlipämischen Tieren die des Cholesterins im Serum nicht herabgesetzt. Die übrigen Lipidfraktionen verhalten sich wie im ersten Versuch. 相似文献
192.
193.
Zusammenfassung Mäuse wurden mit Kasein- und Streptokokkus-Antigen injiziert. In den immunisierten Tieren ist die Ausscheidungsgeschwindigkeit von i.v. injiziertem Albumin-I131 aus dem Plasma erniedrigt, und ebenso ist im Vergleich zu den Kontrolltieren der transvaskuläre Transport in die Haut reduziert. 相似文献
194.
Monsuur AJ de Bakker PI Alizadeh BZ Zhernakova A Bevova MR Strengman E Franke L van't Slot R van Belzen MJ Lavrijsen IC Diosdado B Daly MJ Mulder CJ Mearin ML Meijer JW Meijer GA van Oort E Wapenaar MC Koeleman BP Wijmenga C 《Nature genetics》2005,37(12):1341-1344
Celiac disease is probably the best-understood immune-related disorder. The disease presents in the small intestine and results from the interplay between multiple genes and gluten, the triggering environmental factor. Although HLA class II genes explain 40% of the heritable risk, non-HLA genes accounting for most of the familial clustering have not yet been identified. Here we report significant and replicable association (P = 2.1 x 10(-6)) to a common variant located in intron 28 of the gene myosin IXB (MYO9B), which encodes an unconventional myosin molecule that has a role in actin remodeling of epithelial enterocytes. Individuals homozygous with respect to the at-risk allele have a 2.3-times higher risk of celiac disease (P = 1.55 x 10(-5)). This result is suggestive of a primary impairment of the intestinal barrier in the etiology of celiac disease, which may explain why immunogenic gluten peptides are able to pass through the epithelial barrier. 相似文献
195.
Szeltner Z Alshafee I Juhász T Parvari R Polgár L 《Cellular and molecular life sciences : CMLS》2005,62(19-20):2376-2381
The PREPL (previously called KIAA0436) gene encodes a putative serine peptidase from the prolyl oligopeptidase family. A chromosomal deletion involving the PREPL gene leads to a severe syndrome with multiple symptoms. Homology with oligopeptidase B suggested that the enzyme cleaves after an arginine or lysine residue. Several PREPL splice variants have been identified, and a 638-residue variant (PREPL A) was expressed in Escherichia coli and purified. Its secondary structure was similar to that of oligopeptidase B, but differential-scanning calorimetry indicated a higher conformational stability. Dimerization may account for the enhanced stability. Unexpectedly, the PREPL A protein did not cleave peptide substrates containing a P1 basic residue, but did slowly hydrolyse an activated ester substrate, and reacted with diisopropyl fluorophosphate. These results indicated that the catalytic serine is a reactive residue. However, the negligible hydrolytic activity suggests that the function of PREPL A is different from that of the other members of the prolyl oligopeptidase family. 相似文献
196.
Mannella N Yang WL Zhou XJ Zheng H Mitchell JF Zaanen J Devereaux TP Nagaosa N Hussain Z Shen ZX 《Nature》2005,438(7067):474-478
A characteristic feature of the copper oxide high-temperature superconductors is the dichotomy between the electronic excitations along the nodal (diagonal) and antinodal (parallel to the Cu-O bonds) directions in momentum space, generally assumed to be linked to the 'd-wave' symmetry of the superconducting state. Angle-resolved photoemission measurements in the superconducting state have revealed a quasiparticle spectrum with a d-wave gap structure that exhibits a maximum along the antinodal direction and vanishes along the nodal direction. Subsequent measurements have shown that, at low doping levels, this gap structure persists even in the high-temperature metallic state, although the nodal points of the superconducting state spread out in finite 'Fermi arcs'. This is the so-called pseudogap phase, and it has been assumed that it is closely linked to the superconducting state, either by assigning it to fluctuating superconductivity or by invoking orders which are natural competitors of d-wave superconductors. Here we report experimental evidence that a very similar pseudogap state with a nodal-antinodal dichotomous character exists in a system that is markedly different from a superconductor: the ferromagnetic metallic groundstate of the colossal magnetoresistive bilayer manganite La1.2Sr1.8Mn2O7. Our findings therefore cast doubt on the assumption that the pseudogap state in the copper oxides and the nodal-antinodal dichotomy are hallmarks of the superconductivity state. 相似文献
197.
CD36 is a sensor of diacylglycerides 总被引:1,自引:0,他引:1
Hoebe K Georgel P Rutschmann S Du X Mudd S Crozat K Sovath S Shamel L Hartung T Zähringer U Beutler B 《Nature》2005,433(7025):523-527
Toll-like receptor 2 (TLR2) is required for the recognition of numerous molecular components of bacteria, fungi and protozoa. The breadth of the ligand repertoire seems unusual, even if one considers that TLR2 may form heteromers with TLRs 1 and 6 (ref. 12), and it is likely that additional proteins serve as adapters for TLR2 activation. Here we show that an N-ethyl-N-nitrosourea-induced nonsense mutation of Cd36 (oblivious) causes a recessive immunodeficiency phenotype in which macrophages are insensitive to the R-enantiomer of MALP-2 (a diacylated bacterial lipopeptide) and to lipoteichoic acid. Homozygous mice are hypersusceptible to Staphylococcus aureus infection. Cd36(obl) macrophages readily detect S-MALP-2, PAM(2)CSK(4), PAM(3)CSK(4) and zymosan, revealing that some--but not all--TLR2 ligands are dependent on CD36. Already known as a receptor for endogenous molecules, CD36 is also a selective and nonredundant sensor of microbial diacylglycerides that signal via the TLR2/6 heterodimer. 相似文献
198.
199.
Z. Šormová K. Šebesta J. Bauerová O. Melichar F. Šorm 《Cellular and molecular life sciences : CMLS》1960,16(5):189-190
Zusammenfassung Es wurde eine entwicklungsfördernde Wirkung von 5-Bromuracil und 5-Nitrouracil bereits in geringen Mengen auf manche Pflanzen (unter anderem Tomaten, Gurken und Gartenlattich) festgestellt. 5-Bromuracil wird dabei nicht in die Pflanzennukleinsäuren eingebaut, sondern unterliegt einem schnellen Abbau; weiterhin verursacht der Stoff eine Hemmung des Uracilabbaues. Die Möglichkeit einer Beeinflussung der genetischen Eigenschaften wird diskutiert. 相似文献
200.
Summary The addition of simple quaternary salts (as I and II) to solutions of local anaesthetics, effects a pronounced prolongation of the time of complete infiltration anaesthesia. These salts have no effect on the time of surface anaesthesia. Other pharmacological characteristics of these mixtures were also determined. 相似文献