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81.
Reversible switching between superhydrophobic states on a hierarchically structured surface 总被引:1,自引:0,他引:1
Verho T Korhonen JT Sainiemi L Jokinen V Bower C Franze K Franssila S Andrew P Ikkala O Ras RH 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(26):10210-10213
Nature offers exciting examples for functional wetting properties based on superhydrophobicity, such as the self-cleaning surfaces on plant leaves and trapped air on immersed insect surfaces allowing underwater breathing. They inspire biomimetic approaches in science and technology. Superhydrophobicity relies on the Cassie wetting state where air is trapped within the surface topography. Pressure can trigger an irreversible transition from the Cassie state to the Wenzel state with no trapped air--this transition is usually detrimental for nonwetting functionality and is to be avoided. Here we present a new type of reversible, localized and instantaneous transition between two Cassie wetting states, enabled by two-level (dual-scale) topography of a superhydrophobic surface, that allows writing, erasing, rewriting and storing of optically displayed information in plastrons related to different length scales. 相似文献
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Bach A Clausen BH Møller M Vestergaard B Chi CN Round A Sørensen PL Nissen KB Kastrup JS Gajhede M Jemth P Kristensen AS Lundström P Lambertsen KL Strømgaard K 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(9):3317-3322
Inhibition of the ternary protein complex of the synaptic scaffolding protein postsynaptic density protein-95 (PSD-95), neuronal nitric oxide synthase (nNOS), and the N-methyl-D-aspartate (NMDA) receptor is a potential strategy for treating ischemic brain damage, but high-affinity inhibitors are lacking. Here we report the design and synthesis of a novel dimeric inhibitor, Tat-NPEG4(IETDV)(2) (Tat-N-dimer), which binds the tandem PDZ1-2 domain of PSD-95 with an unprecedented high affinity of 4.6 nM, and displays extensive protease-resistance as evaluated in vitro by stability-measurements in human blood plasma. X-ray crystallography, NMR, and small-angle X-ray scattering (SAXS) deduced a true bivalent interaction between dimeric inhibitor and PDZ1-2, and also provided a dynamic model of the conformational changes of PDZ1-2 induced by the dimeric inhibitor. A single intravenous injection of Tat-N-dimer (3 nmol/g) to mice subjected to focal cerebral ischemia reduces infarct volume with 40% and restores motor functions. Thus, Tat-N-dimer is a highly efficacious neuroprotective agent with therapeutic potential in stroke. 相似文献
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Bang CN Greve AM Boman K Egstrup K Gohlke-Baerwolf C Køber L Nienaber CA Ray S Rossebø AB Wachtell K 《American heart journal》2012,163(4):690-696
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Objectives: The aim of the present prospective clinical study was to evaluate the match between the positions and axes of the virtually planned and the placed implants using laboratory‐based surgical guides generated from cone beam computed tomography (CBCT). Materials and methods: A total of 132 implants were placed with the aid of 3D‐based transfer templates in 52 consecutive partially edentulous patients between April 2008 and March 2010. After individual adaptation of the scan templates and CBCT scanning, the acquired data for virtual implant planning and simulation were processed using the med3D software program. After finalizing the virtual placement of the implants the radiographic templates were converted into operative guides containing titanium sleeves for cavity preparation. Preoperative planning was merged with postoperative CBCT data to identify linear and angular deviations between virtually planned and placed implants. Results: Compared with the planned implants the installed implants showed linear deviations in the median at the neck and apex of 0.27 mm (range 0.01–0.97 mm), and of 0.46 mm (range 0.03–1.38 mm), respectively. The angle deviation was 1.84° in median, with a range of 0.07–6.26°. The extent of deviation depends on the size of the tooth gap and the distribution of the remaining teeth. Conclusion: The results of this study suggested that laboratory‐fabricated surgical guides using CBCT data may be reliable in implant placement under prosthodontic considerations in partial edentulism. To cite this article: Behneke A, Burwinkel M, Knierim K, Behneke N. Accuracy assessment of cone beam computed tomography‐derived laboratory‐based surgical templates on partially edentulous patients.Clin. Oral Impl. Res. 23 , 2012; 137–143. doi: 10.1111/j.1600‐0501.2011.02176.x 相似文献
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Czuczman MS Hess G Gadeberg OV Pedersen LM Goldstein N Gupta I Jewell RC Lin TS Lisby S Strange C Windfeld K Viardot A; Study Investigators 《British journal of haematology》2012,157(4):438-445
An international, Phase II trial was conducted to assess two doses of ofatumumab, a human CD20 monoclonal antibody, combined with cyclophosphamide (750 mg/m2), doxorubicin (50 mg/m2), prednisone (100 mg days 3–7) and vincristine (1·4 mg/m2) (O‐CHOP), as frontline treatment for follicular lymphoma (FL). 59 patients with previously untreated FL were randomized to ofatumumab 500 mg (n = 29) or 1000 mg (n = 30) day 1, with CHOP on day 3 every 3 weeks for six cycles. Median duration of FL was 0·1 years for both dose groups; 34% and 38% of patients had high‐risk Follicular Lymphoma International Prognostic Index (FLIPI) scores in the 500‐ and 1000‐mg dose groups, respectively. Overall response rate was 90% for the 500‐mg group and 100% for the 1000‐mg group. 62% of patients achieved complete response (CR)/unconfirmed CR (CRu). 76% of patients with FLIPI score 3–5 attained CR/CRu. Longer follow‐up time is needed for analysis of survival end points. The most common Common Terminology Criteria grade 3–4 investigator‐reported adverse events were leucopenia (29%) and neutropenia (22%). No deaths have been reported. O‐CHOP was safe and efficacious in patients with previously untreated FL, including high‐risk FLIPI groups. This trial was registered at www.clinicaltrials.gov (NCT00494780). 相似文献
87.
Thygesen K Mair J Giannitsis E Mueller C Lindahl B Blankenberg S Huber K Plebani M Biasucci LM Tubaro M Collinson P Venge P Hasin Y Galvani M Koenig W Hamm C Alpert JS Katus H Jaffe AS;the Study Group on Biomarkers in Cardiology of the ESC Working Group on Acute Cardiac Care 《European heart journal》2012,33(18):2252-2257
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