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91.
Summary : FT is a tool written in C++, which implements the Fourier analysis method to locate periodicities in aminoacid or DNA sequences. It is provided for free public use on a WWW server with a Java interface. Availability : The server address is http://o2.db. uoa.gr/FT Contact : shamodr@atlas.uoa.gr   相似文献   
92.
Suckling and allosuckling were studied in relation to the age and sex of fawns in a captive population of fallow deer (Dama dama) showing a high rate of allosuckling (73% of the suckling bouts). No difference occurred between the sexes in either the duration or frequency of suckling and allosuckling. The frequency of suckling bouts decreased rapidly during the first four weeks of life while the frequency of allosuckling bouts increased rapidly between the second and the third week and remained constant until the conclusion of the observations (11th week of life). Birth date affected allosuckling, with late-born fawns performing fewer and shorter allosuckling bouts. The lack of a negative relationship between suckling and allosuckling frequencies failed to confirm the hypothesis that allosuckling allows fawns to complete their milk requirements on foster mothers. Both inbreeding and crowding could explain the absence of particular relationship between fawns and foster mothers.  相似文献   
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Objectives

We reviewed the literature on interventions that aimed to improve hospital-to-school reintegration for children and youth with acquired brain injury (ABI). ABI is the leading cause of disability among children and youth. A successful hospital-to-school reintegration process is essential to the rehabilitative process. However, little is known about the effective components of of such interventions.

Methods and findings

Our research team conducted a systematic review, completing comprehensive searches of seven databases and selected reference lists for relevant articles published in a peer-reviewed journal between 1989 and June 2014. We selected articles for inclusion that report on studies involving: a clinical population with ABI; sample had an average age of 20 years or younger; an intentional structured intervention affecting hospital-to-school transitions or related components; an experimental design; and a statistically evaluated health outcome. Two independent reviewers applied our inclusion criteria, extracted data, and rated study quality. A meta-analysis was not feasible due to the heterogeneity of the studies reported. Of the 6933 articles identified in our initial search, 17 articles (reporting on 350 preadolescents and adolescents, aged 4–19, (average age 11.5 years, SD: 2.21) met our inclusion criteria. They reported on interventions varying in number of sessions (one to 119) and session length (20 minutes to 4 hours). The majority of interventions involved multiple one-to-one sessions conducted by a trained clinician or educator, homework activities, and parental involvement. The interventions were delivered through different settings and media, including hospitals, schools, and online. Although outcomes varied (with effect sizes ranging from small to large), 14 of the articles reported at least one significant improvement in cognitive, social, psychological, or behavioral functioning or knowledge of ABI.

Conclusions

Cognitive, behavioral, and problem-solving interventions have the potential to improve school reintegration for youth with ABI. However, more comprehensive interventions are needed to help link rehabilitation clinicians, educators, adolescents, and families.  相似文献   
96.
Functional selectivity (or biased agonism) is a property exhibited by some G protein-coupled receptor (GPCR) ligands, which results in the modulation of a subset of a receptor’s signaling capabilities and more precise control over complex biological processes. The dopamine D2 receptor (D2R) exhibits pleiotropic responses to the biogenic amine dopamine (DA) to mediate complex central nervous system functions through activation of G proteins and β-arrestins. D2R is a prominent therapeutic target for psychological and neurological disorders in which DA biology is dysregulated and targeting D2R with functionally selective drugs could provide a means by which pharmacotherapies could be developed. However, factors that determine GPCR functional selectivity in vivo may be multiple with receptors, ligands and transducers contributing to the process. We have recently described a mutagenesis approach to engineer biased D2R mutants in which G protein-dependent ([Gprot]D2R) and β-arrestin-dependent signaling ([βarr]D2R) were successfully separated (Peterson, et al. PNAS, 2015). Here, permutations of these mutants were used to identify critical determinants of the D2R signaling complex that impart signaling bias in response to the natural or synthetic ligands. Critical residues identified in generating [Gprot]D2R and [βarr]D2R conferred control of partial agonism at G protein and/or β-arrestin activity. Another set of mutations that result in G protein bias was identified that demonstrated that full agonists can impart unique activation patterns, and provided further credence to the concept of ligand texture. Finally, the contributions and interplay between different transducers indicated that G proteins are not aberrantly activated, and that receptor kinase and β-arrestin activities are inextricably linked. These data provide a thorough elucidation of the feasibility and malleability of D2R functional selectivity and point to means by which novel in vivo therapies could be modeled.  相似文献   
97.
Metastatic cancer causes 90% of cancer deaths. Unlike many primary tumors, metastatic tumors cannot be cured by surgery alone. Metastatic cancer requires chemotherapy. However, metastatic cells are not easily killed by chemotherapy. These problems with chemotherapy are caused in part by the metastatic cell niche: hypoxia. Here we show that the molecule, methyl sulfone, normalized metastatic metabolism of hypoxic breast cancer and melanoma cells by altering several metabolic functions of the cells. Under hypoxia, methyl sulfone decreased expression of the master regulator of hypoxia, HIF-1α, and reduced levels of the glycolytic enzymes, PKM2, LDHA, GLUT1, the pro-angiogenic protein, VEGF, and the iron-sulfur metabolism molecules, miR-210 and transferrin, all of which promote metastasis. Conversely, methyl sulfone increased levels of ISCU1/2 and ferroportin, proteins associated with iron-sulfur cluster biogenesis and iron homeostasis in normal cells. These data identify methyl sulfone as a multi-targeting molecule that blocks the survival/proliferative effect of hypoxia on metastatic cells and brings normality back to cellular metabolism.  相似文献   
98.
The aim of the present study was to investigate long term effects of motor denervation by botulinum toxin complex type A (BoNT/A) from Clostridium Botulinum, on the afferent fibers originating from the gastrocnemius muscle of rats. Animals were divided in 2 experimental groups: 1) untreated animals acting as control and 2) treated animals in which the toxin was injected in the left muscle, the latter being itself divided into 3 subgroups according to their locomotor recovery with the help of a test based on footprint measurements of walking rats: i) no recovery (B0), ii) 50% recovery (B50) and iii) full recovery (B100). Then, muscle properties, metabosensitive afferent fiber responses to potassium chloride (KCl) and lactic acid injections and Electrically-Induced Fatigue (EIF), and mechanosensitive responses to tendon vibrations were measured. At the end of the experiment, rats were killed and the toxin injected muscles were weighted. After toxin injection, we observed a complete paralysis associated to a loss of force to muscle stimulation and a significant muscle atrophy, and a return to baseline when the animals recover. The response to fatigue was only decreased in the B0 group. The responses to KCl injections were only altered in the B100 groups while responses to lactic acid were altered in the 3 injected groups. Finally, our results indicated that neurotoxin altered the biphasic pattern of response of the mechanosensitive fiber to tendon vibrations in the B0 and B50 groups. These results indicated that neurotoxin injection induces muscle afferent activity alterations that persist and even worsen when the muscle has recovered his motor activity.  相似文献   
99.
Pettersson Stolk, S., Holmer, L. E. and Caron, J ‐B. 2010. First record of the brachiopod Lingulella waptaensis with pedicle from the Middle Cambrian Burgess Shale. —Acta Zoologica (Stockholm) 91 : 150–162 The organophosphatic shells of linguloid brachiopods are a common component of normal Cambrian–Ordovician shelly assemblages. Preservation of linguloid soft‐part anatomy, however, is extremely rare, and restricted to a few species in Lower Cambrian Konservat Lagerstätten. Such remarkable occurrences provide unique insights into the biology and ecology of early linguloids that are not available from the study of shells alone. Based on its shells, Lingulella waptaensis Walcott, was originally described in 1924 from the Middle Cambrian Burgess Shale but despite the widespread occurrence of soft‐part preservation associated with fossils from the same levels, no preserved soft parts have been reported. Lingulella waptaensis is restudied herein based on 396 specimens collected by Royal Ontario Museum field parties from the Greater Phyllopod Bed (Walcott Quarry Shale Member, British Columbia). The new specimens, including three with exceptional preservation of the pedicle, were collected in situ in discrete obrution beds. Census counts show that L. waptaensis is rare but recurrent in the Greater Phyllopod Bed, suggesting that this species might have been generalist. The wrinkled pedicle protruded posteriorly between the valves, was composed of a central coelomic space, and was slender and flexible enough to be tightly folded, suggesting a thin chitinous cuticle and underlying muscular layers. The nearly circular shell and the long, slender and highly flexible pedicle suggest that L. waptaensis lived epifaunally, probably attached to the substrate. Vertical cross‐sections of the shells show that L. waptaensis possessed a virgose secondary layer, which has previously only been known from Devonian to Recent members of the Family Lingulidae.  相似文献   
100.
Pertechnetate is rapidly reduced in concentrated (8.7 M) HBr to Tc(V). Subsequently reduction to give TcBr62? is a slow process. The kinetics of this last process have been investigated. They indicated a combination of first and zero order reactions in the presence of the high HBr concentration. The first order rate constant was 4.8 × 10?2 h?1, and the zero order process constant was 6.0 × 10?6 mol l?1 h?1.  相似文献   
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