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排序方式: 共有201条查询结果,搜索用时 15 毫秒
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Zusammenfassung Mit einem Oxytocin-Albumin-Konjugat bzw. mit einem Lysin-Vasopressin-Albumin-Konjugat konnten bei Kaninchen spezifische Antikörper hervorgerufen werden. Die gegen Oxytocin-Albumin-Konjugat gerichteten Antikörper scheinen auch einen gewissen inaktivierenden Effekt auf genuines Oxytocin zu haben. 相似文献
63.
Summary A lectin fromViscum album which specifically binds to D-galactose was isolated by affinity chromatography on O-lactosyl-, O-galactosyl-polycarylamide or hydrolized sepharose 4 B. Some serological and physicochemical properties of the agglutinin are reported. 相似文献
64.
Hearing depends on a high K(+) concentration bathing the apical membranes of sensory hair cells. K(+) that has entered hair cells through apical mechanosensitive channels is transported to the stria vascularis for re-secretion into the scala media(). K(+) probably exits outer hair cells by KCNQ4 K(+) channels(), and is then transported by means of a gap junction system connecting supporting Deiters' cells and fibrocytes() back to the stria vascularis. We show here that mice lacking the K(+)/Cl(-) (K-Cl) co-transporter Kcc4 (coded for by Slc12a7) are deaf because their hair cells degenerate rapidly after the beginning of hearing. In the mature organ of Corti, Kcc4 is restricted to supporting cells of outer and inner hair cells. Our data suggest that Kcc4 is important for K(+) recycling() by siphoning K(+) ions after their exit from outer hair cells into supporting Deiters' cells, where K(+) enters the gap junction pathway. Similar to some human genetic syndromes(), deafness in Kcc4-deficient mice is associated with renal tubular acidosis. It probably results from an impairment of Cl(-) recycling across the basolateral membrane of acid-secreting alpha-intercalated cells of the distal nephron. 相似文献
65.
Timm Schubert Corinna Gleiser Peter Heiduschka Christoph Franz Kerstin Nagel-Wolfrum Ayse Sahaboglu Nicole Weisschuh Gordon Eske Karin Rohbock Norman Rieger François Paquet-Durand Bernd Wissinger Uwe Wolfrum Bernhard Hirt Wibke Singer Lukas Rüttiger Ulrike Zimmermann Marlies Knipper 《Cellular and molecular life sciences : CMLS》2015,72(20):3953-3969
66.
West AP Brodsky IE Rahner C Woo DK Erdjument-Bromage H Tempst P Walsh MC Choi Y Shadel GS Ghosh S 《Nature》2011,472(7344):476-480
Reactive oxygen species (ROS) are essential components of the innate immune response against intracellular bacteria and it is thought that professional phagocytes generate ROS primarily via the phagosomal NADPH oxidase machinery. However, recent studies have suggested that mitochondrial ROS (mROS) also contribute to mouse macrophage bactericidal activity, although the mechanisms linking innate immune signalling to mitochondria for mROS generation remain unclear. Here we demonstrate that engagement of a subset of Toll-like receptors (TLR1, TLR2 and TLR4) results in the recruitment of mitochondria to macrophage phagosomes and augments mROS production. This response involves translocation of a TLR signalling adaptor, tumour necrosis factor receptor-associated factor 6 (TRAF6), to mitochondria, where it engages the protein ECSIT (evolutionarily conserved signalling intermediate in Toll pathways), which is implicated in mitochondrial respiratory chain assembly. Interaction with TRAF6 leads to ECSIT ubiquitination and enrichment at the mitochondrial periphery, resulting in increased mitochondrial and cellular ROS generation. ECSIT- and TRAF6-depleted macrophages have decreased levels of TLR-induced ROS and are significantly impaired in their ability to kill intracellular bacteria. Additionally, reducing macrophage mROS levels by expressing catalase in mitochondria results in defective bacterial killing, confirming the role of mROS in bactericidal activity. These results reveal a novel pathway linking innate immune signalling to mitochondria, implicate mROS as an important component of antibacterial responses and further establish mitochondria as hubs for innate immune signalling. 相似文献
67.
Chapman HN Fromme P Barty A White TA Kirian RA Aquila A Hunter MS Schulz J DePonte DP Weierstall U Doak RB Maia FR Martin AV Schlichting I Lomb L Coppola N Shoeman RL Epp SW Hartmann R Rolles D Rudenko A Foucar L Kimmel N Weidenspointner G Holl P Liang M Barthelmess M Caleman C Boutet S Bogan MJ Krzywinski J Bostedt C Bajt S Gumprecht L Rudek B Erk B Schmidt C Hömke A Reich C Pietschner D Strüder L Hauser G Gorke H Ullrich J Herrmann S Schaller G Schopper F Soltau H Kühnel KU Messerschmidt M 《Nature》2011,470(7332):73-77
X-ray crystallography provides the vast majority of macromolecular structures, but the success of the method relies on growing crystals of sufficient size. In conventional measurements, the necessary increase in X-ray dose to record data from crystals that are too small leads to extensive damage before a diffraction signal can be recorded. It is particularly challenging to obtain large, well-diffracting crystals of membrane proteins, for which fewer than 300 unique structures have been determined despite their importance in all living cells. Here we present a method for structure determination where single-crystal X-ray diffraction 'snapshots' are collected from a fully hydrated stream of nanocrystals using femtosecond pulses from a hard-X-ray free-electron laser, the Linac Coherent Light Source. We prove this concept with nanocrystals of photosystem I, one of the largest membrane protein complexes. More than 3,000,000 diffraction patterns were collected in this study, and a three-dimensional data set was assembled from individual photosystem I nanocrystals (~200?nm to 2?μm in size). We mitigate the problem of radiation damage in crystallography by using pulses briefer than the timescale of most damage processes. This offers a new approach to structure determination of macromolecules that do not yield crystals of sufficient size for studies using conventional radiation sources or are particularly sensitive to radiation damage. 相似文献
68.
Najmabadi H Hu H Garshasbi M Zemojtel T Abedini SS Chen W Hosseini M Behjati F Haas S Jamali P Zecha A Mohseni M Püttmann L Vahid LN Jensen C Moheb LA Bienek M Larti F Mueller I Weissmann R Darvish H Wrogemann K Hadavi V Lipkowitz B Esmaeeli-Nieh S Wieczorek D Kariminejad R Firouzabadi SG Cohen M Fattahi Z Rost I Mojahedi F Hertzberg C Dehghan A Rajab A Banavandi MJ Hoffer J Falah M Musante L Kalscheuer V Ullmann R Kuss AW Tzschach A Kahrizi K Ropers HH 《Nature》2011,478(7367):57-63
69.
Lapkiewicz R Li P Schaeff C Langford NK Ramelow S Wieśniak M Zeilinger A 《Nature》2011,474(7352):490-493
In contrast to classical physics, quantum theory demands that not all properties can be simultaneously well defined; the Heisenberg uncertainty principle is a manifestation of this fact. Alternatives have been explored--notably theories relying on joint probability distributions or non-contextual hidden-variable models, in which the properties of a system are defined independently of their own measurement and any other measurements that are made. Various deep theoretical results imply that such theories are in conflict with quantum mechanics. Simpler cases demonstrating this conflict have been found and tested experimentally with pairs of quantum bits (qubits). Recently, an inequality satisfied by non-contextual hidden-variable models and violated by quantum mechanics for all states of two qubits was introduced and tested experimentally. A single three-state system (a qutrit) is the simplest system in which such a contradiction is possible; moreover, the contradiction cannot result from entanglement between subsystems, because such a three-state system is indivisible. Here we report an experiment with single photonic qutrits which provides evidence that no joint probability distribution describing the outcomes of all possible measurements--and, therefore, no non-contextual theory--can exist. Specifically, we observe a violation of the Bell-type inequality found by Klyachko, Can, Binicio?lu and Shumovsky. Our results illustrate a deep incompatibility between quantum mechanics and classical physics that cannot in any way result from entanglement. 相似文献
70.