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排序方式: 共有2033条查询结果,搜索用时 15 毫秒
961.
R Aversano MR Ercolano I Caruso C Fasano D Rosellini D Carputo 《International journal of molecular sciences》2012,13(8):10316-10335
Polyploidy is a very common phenomenon in the plant kingdom, where even diploid species are often described as paleopolyploids. The polyploid condition may bring about several advantages compared to the diploid state. Polyploids often show phenotypes that are not present in their diploid progenitors or exceed the range of the contributing species. Some of these traits may play a role in heterosis or could favor adaptation to new ecological niches. Advances in genomics and sequencing technology may create unprecedented opportunities for discovering and monitoring the molecular effects of polyploidization. Through this review, we provide an overview of technologies and strategies that may allow an in-depth analysis of polyploid genomes. After introducing some basic aspects on the origin and genetics of polyploids, we highlight the main tools available for genome and gene expression analysis and summarize major findings. In the last part of this review, the implications of next generation sequencing are briefly discussed. The accumulation of knowledge on polyploid formation, maintenance, and divergence at whole-genome and subgenome levels will not only help plant biologists to understand how plants have evolved and diversified, but also assist plant breeders in designing new strategies for crop improvement. 相似文献
962.
Manzoni L Belvisi L Arosio D Bartolomeo MP Bianchi A Brioschi C Buonsanti F Cabella C Casagrande C Civera M De Matteo M Fugazza L Lattuada L Maisano F Miragoli L Neira C Pilkington-Miksa M Scolastico C 《ChemMedChem》2012,7(6):1084-1093
We report the synthesis of novel chelates of Gd and (68)Ga with DPTA, DOTA, HP-DOA3, as well as with AAZTA, a novel chelating agent developed by our research group. These chelating agents were appropriately conjugated, prior to metal complexation, with DB58, an RGD peptidomimetic, conformationally constrained on an azabicycloalkane scaffold and endowed with high affinity for integrin α(ν)β(3) . Because α(ν)β(3) is involved in neo-angiogenesis in solid tumors and is also directly expressed in cancer cells (e.g. glioblastomas, melanomas) and ovarian, breast, and prostate cancers, these constructs could prove useful as molecular imaging probes in cancer diagnosis by MRI or PET techniques. Molecular modeling, integrin binding assays, and relaxivity assessments allowed the selection of compounds suitable for multiple expression on dendrimeric or nanoparticulate structures. These results also led us to an exploratory investigation of (68)Ga complexation for the promising (68)Ga-PET technique; the AAZTA complex 15((68)Ga) exhibited uptake in a xenograft model of glioblastoma, suggesting potentially useful developments with new probes with improved affinity. 相似文献
963.
Gossett DR Tse HT Dudani JS Goda K Woods TA Graves SW Di Carlo D 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(17):2757-2764
A general strategy for controlling particle movement across streams would enable new capabilities in single-cell analysis, solid-phase reaction control, and biophysics research. Transferring cells across streams is difficult to achieve in a well-controlled manner, since it requires precise control of fluid flow along with external force fields or precisely manufactured mechanical structures. Herein a strategy is introduced for particle transfer based on passive inertial lift forces and shifts in the distribution of these forces for channels with shifting aspect ratios. Uniquely, use of the dominant wall-effect lift parallel to the particle rotation direction is explored and utilized to achieve controllable cross-stream motion. In this way, particles are positioned to migrate across laminar streams and enter a new solution without significant disturbance of the interface at rates exceeding 1000 particles per second and sub-millisecond transfer times. The capabilities of rapid inertial solution exchange (RInSE) for preparation of hematological samples and other cellular assays are demonstrated. Lastly, improvements to inline flow cytometry after RInSE of excess fluorescent dye and focusing for downstream analysis are characterized. The described approach is simply applied to manipulating cells and particles and quickly exposing them to or removing them from a reacting solution, with broader applications in control and analysis of low affinity interactions on cells or particles. 相似文献
964.
Riccardo Lencioni Simona Ortori Dania Cioni Girolamo Morelli Enrico Ceretti Mirco Cosottini Ilario Menchi Carlo Bartolozzi 《Magma (New York, N.Y.)》1999,8(2):91-97
The purpose of this study was to illustrate the spectrum of abnormalities found at endorectal coil magnetic resonance (MR)
imaging in patients with hemospermia. Ninety patients aged between 23 and 71 years (mean age 41 years) presenting with hemospermia
underwent evaluation with endorectal coil MR imaging at 1.5 T. Duration of hemospermia ranged between 5 days and 4 years (mean
15 months). MR examination protocol included T1-weighted spin-echo (SE) and T2-weighted fast SE MR images obtained in the
sagittal, coronal, and axial planes. Abnormalities were observed on endorectal-coil MR images in 49 of 90 patients (54%).
Blood within the seminal vesicle or the ejaculatory duct was recognized in 23 of 90 patients (25%). Dilatation of the seminal
vesicles or the ejaculatory duct was observed in 31 of 90 patients (34%). Cystic lesions were identified in 14 cases, eight
of which involved the utriculus and six the ejaculatory duct. Calculi within the seminal vesicles were depicted in seven patients.
No malignant disease was demonstrated. In conclusion, despite the evidence that hemospermia is most often a benign and self-limiting
condition, we found that endorectal coil MR imaging can detect abnormal findings in more than half of the patients, and may
be helpful in assessing the level at which hemorrhage occurred and in defining the cause of the disease.
Presented as Category I Scientific Exhibit at the 1996 Annual Meeting of the Radiological Society of North America. 相似文献
965.
Production of Hypoallergenic Foods from Apricots 总被引:1,自引:0,他引:1
Oreste Vittore Bernna Carlo Pomei Valerio Pravettoni Laura Farioli Elide Anna Pastorello 《Journal of food science》2005,70(1):S38-S41
ABSTRACT: Food allergy is a growing problem because more and more people are suffering from this kind of illness. Besides allergies to staple foods such as milk, fish, and eggs, many fruits are known to cause allergy; those of the family of Rosaceae , such as peaches and apricots, are prominent among them, especially in the Mediterranean area. In this work, we report on the results obtained when preparing hypoallergenic and anallergenic derivatives starting from fresh apricots. Protein extracts from 9 cultivars of apricot, either unpeeled or chemically peeled, were prepared and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting, to evaluate the presence of the allergen Pru ar 3, the main protein responsible for causing the oral allergy syndrome (OAS). The chemical peeling of fruits proved determinant for our aim and allowed us to develop a new production process for some hypoallergenic and anallergenic derivatives starting out from apricot purée, such as nectar, limpid juice, jam, and fruit jelly, which can be consumed as they are or used as fillings in yogurt, snacks, and so on. 相似文献
966.
Costa Alberto; Perri Roberta; Serra Laura; Barban Francesco; Gatto Ilaria; Zabberoni Silvia; Caltagirone Carlo; Carlesimo Giovanni A. 《Canadian Metallurgical Quarterly》2010,24(3):327
Objective: The present study aimed to investigate prospective memory (PM) in persons with mild cognitive impairment (MCI). Method: Twenty individuals with MCI (10 with an amnestic profile and 10 with a dysexecutive profile of cognitive impairment) and 20 control subjects (CS) were recruited. In the PM tasks, subjects had to execute three actions after 20 min had elapsed (time-based condition) or after a timer rang (event-based condition). Separate scores were computed for correct recall of the intention to perform the actions (prospective component) and for correct execution of the actions (retrospective component). Results: Although individuals with MCI were less accurate than CS in both prospective (Cohen's d ranged from 1.04 to 2.23) and retrospective (Cohen's d ranged from 0.81 to 1.06) components of the experimental task, they were significantly more impaired in the former than the latter component (Cohen's d = 0.42). Moreover, the deficit in the prospective component of the time-based task was particularly evident in MCI participants presenting with a dysexecutive impairment in respect to amnestic MCI individuals (Cohen's d = 0.99). Conclusions: Results of the present study show that the ability of subjects with MCI to comply effectively with a planned delayed intention is impaired and suggest that dysexecutive disorders are likely responsible for this deficit. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
967.
968.
Abramo Antonio Blanchini Franco Geretti Luca Savorgnan Carlo 《Mobile Computing, IEEE Transactions on》2008,7(11):1325-1337
In this paper the indoor wireless localization problem is addressed both from the theoretical and application standpoints. The main result of the paper is on the theoretical side: the topological definition of regular and irregular nodes is introduced, and formal results are presented to support regularity as a desirable network property for the attainment of precise node localization. In force of this definition, a mixed convex/non—convex optimization approach has been derived for the solution of the positioning problem. The two procedures, suitably combined, allow the achievement of better convergence towards the best positioning of a multitude of blind wireless nodes. A completely decentralized, partially asynchronous algorithm is presented, which proceeds locally on each node based on the sole knowledge of the distances measured from, and of the estimated positions of the connected nodes only. Its repeated asynchronous application on each nodes guarantees the convergence of the algorithm to the positioning of the whole network, even in presence of a limited number of peripheral reference points. Indeed, no global information is required for the proper functioning of the algorithm. Simulations of relevant case studies have been performed to qualify the proposed scheme in realistic conditions, and the results are presented. 相似文献
969.
Stephan Blankenburg Marco Bieri Roman Fasel Klaus Müllen Carlo A. Pignedoli Daniele Passerone 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(20)
The fabrication of nanoscale membranes exhibiting high selectivity is an emerging field of research. The possibility to use bottom‐up approaches to fabricate a filter with porous graphene and analyze its functionality with first principle calculations is investigated. Here, the porous network is produced by self‐assembly of the hexaiodo‐substituted macrocycle cyclohexa‐m‐phenylene (CHP). The resulting porous network exhibits an extremely high selectivity in favor of H2 and He among other atmospheric gases, such as Ne, O2, N2, CO, CO2, NH3, and Ar. The presented membrane is superior to traditional filters using polymers or silica and could have great potential for further technological applications such as gas sensors or fuel cells. 相似文献
970.