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排序方式: 共有859条查询结果,搜索用时 15 毫秒
91.
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Oliver Windram Priyadharshini Madhou Stuart McHattie Claire Hill Richard Hickman Emma Cooke Dafyd J. Jenkins Christopher A. Penfold Laura Baxter Emily Breeze Steven J. Kiddle Johanna Rhodes Susanna Atwell Daniel J. Kliebenstein Youn-sung Kim Oliver Stegle Karsten Borgwardt Cunjin Zhang Alex Tabrett Roxane Legaie Jonathan Moore B?rbel Finkenstadt David L. Wild Andrew Mead David Rand Jim Beynon Sascha Ott Vicky Buchanan-Wollaston Katherine J. Denby 《The Plant cell》2012,24(9):3530-3557
93.
For nearly 70?years, studies have shown large sex differences in human mate selection preferences. However, most of the studies were restricted to a limited set of mate selection criteria and to college students, and neglecting relationship status. In this study, 21,245 heterosexual participants between 18 and 65?years of age (mean age 41) who at the time were not involved in a close relationship rated the importance of 82 mate selection criteria adapted from previous studies, reported age ranges for the oldest and youngest partner that they would find acceptable, and responded to 10 yes/no questions about a potential marriage partner. For nearly all mate selection criteria, women were found to be the more demanding sex, although men placed consistently more value on the physical attractiveness of a potential partner than women. Also, the effects of the participants?? age and level of education were nearly negligible. These results demonstrate the robustness of sex differences in mate selection criteria across a substantial age range. 相似文献
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95.
Wagner S Zensi A Wien SL Tschickardt SE Maier W Vogel T Worek F Pietrzik CU Kreuter J von Briesen H 《PloS one》2012,7(3):e32568
Background
The blood-brain barrier (BBB) represents an insurmountable obstacle for most drugs thus obstructing an effective treatment of many brain diseases. One solution for overcoming this barrier is a transport by binding of these drugs to surface-modified nanoparticles. Especially apolipoprotein E (ApoE) appears to play a major role in the nanoparticle-mediated drug transport across the BBB. However, at present the underlying mechanism is incompletely understood.Methodology/Principal Findings
In this study, the uptake of the ApoE-modified nanoparticles into the brain capillary endothelial cells was investigated to differentiate between active and passive uptake mechanism by flow cytometry and confocal laser scanning microscopy. Furthermore, different in vitro co-incubation experiments were performed with competing ligands of the respective receptor.Conclusions/Significance
This study confirms an active endocytotic uptake mechanism and shows the involvement of low density lipoprotein receptor family members, notably the low density lipoprotein receptor related protein, on the uptake of the ApoE-modified nanoparticles into the brain capillary endothelial cells. This knowledge of the uptake mechanism of ApoE-modified nanoparticles enables future developments to rationally create very specific and effective carriers to overcome the blood-brain barrier. 相似文献96.
Ran Chen Jinu John Antonina Lavrentieva Susann Müller Magda Tomala Yangxi Zhao Robert Zweigerdt Sascha Beutel Bernd Hitzmann Cornelia Kasper Ulrich Martin Ursula Rinas Frank Stahl Thomas Scheper 《Engineering in Life Science》2012,12(1):29-38
Basic fibroblast growth factor (FGF‐2) is a multifunctional cytokine that regulates various cellular processes both in vitro and in vivo. FGF‐2 is extensively used in embryonic stem cell cultures since it can maintain the cells in an undifferentiated state. However, the high price of FGF‐2 has limited its application in stem cell research. Here we present a fast and efficient process for the purification of FGF‐2 from recombinant Escherichia coli cultures using reusable membrane adsorbers. A high expression level of FGF‐2 (42 mg/g dry cell) was achieved by fed‐batch cultivation of E. coli BL21(DE3). A new combination of cation exchange membrane chromatography and heparin‐sepharose affinity chromatography was used for the purification of the protein. A novel anion exchange membrane chromatography was used in the polishing step to remove endotoxins and DNA. In this new process, about 200 mg soluble FGF‐2 was yielded from 1.9 L culture broth with a purity of 98%. The purified protein was identified to be endotoxin‐free and bioactive. It was successfully tested to keep primate embryonic stem cell and human‐induced pluripotent stem cell pluripotent. Our approach, in which a controlled cultivation process is combined with an optimized fast and versatile downstreaming process, is suitable for low‐cost preparation of bioactive FGF‐2 at bench‐scale and may be beneficial to the effective production of other cytokines. 相似文献
97.
Johansson LC Arnlund D White TA Katona G Deponte DP Weierstall U Doak RB Shoeman RL Lomb L Malmerberg E Davidsson J Nass K Liang M Andreasson J Aquila A Bajt S Barthelmess M Barty A Bogan MJ Bostedt C Bozek JD Caleman C Coffee R Coppola N Ekeberg T Epp SW Erk B Fleckenstein H Foucar L Graafsma H Gumprecht L Hajdu J Hampton CY Hartmann R Hartmann A Hauser G Hirsemann H Holl P Hunter MS Kassemeyer S Kimmel N Kirian RA Maia FR Marchesini S Martin AV Reich C Rolles D Rudek B Rudenko A Schlichting I 《Nature methods》2012,9(3):263-265
X-ray free electron laser (X-FEL)-based serial femtosecond crystallography is an emerging method with potential to rapidly advance the challenging field of membrane protein structural biology. Here we recorded interpretable diffraction data from micrometer-sized lipidic sponge phase crystals of the Blastochloris viridis photosynthetic reaction center delivered into an X-FEL beam using a sponge phase micro-jet. 相似文献
98.
Hartenfeller M Zettl H Walter M Rupp M Reisen F Proschak E Weggen S Stark H Schneider G 《PLoS computational biology》2012,8(2):e1002380
We present a computational method for the reaction-based de novo design of drug-like molecules. The software DOGS (Design of Genuine Structures) features a ligand-based strategy for automated ‘in silico’ assembly of potentially novel bioactive compounds. The quality of the designed compounds is assessed by a graph kernel method measuring their similarity to known bioactive reference ligands in terms of structural and pharmacophoric features. We implemented a deterministic compound construction procedure that explicitly considers compound synthesizability, based on a compilation of 25''144 readily available synthetic building blocks and 58 established reaction principles. This enables the software to suggest a synthesis route for each designed compound. Two prospective case studies are presented together with details on the algorithm and its implementation. De novo designed ligand candidates for the human histamine H4 receptor and γ-secretase were synthesized as suggested by the software. The computational approach proved to be suitable for scaffold-hopping from known ligands to novel chemotypes, and for generating bioactive molecules with drug-like properties. 相似文献
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100.