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Data relative to 102 patients seen between 1940 and 1960 with infantile rheumatoid arthritis were analyzed. The systemic nature of the disease and variable early clinical picture make early diagnosis very difficult. Only 20% had articular symptoms at the onset. The youngest was aged 6 months and there was a greater incidence of onset in the first two years of life. Particular attention was paid to the site of original joint involvement as compared with the subsequent final joint pathology. Spindle fingers or swollen proximal interphalangeal joints appear late in the disease but are usually diagnostic of infantile rheumatoid arthritis. Diagnosis is essentially a clinical one; laboratory tests are of little diagnostic value. Prognosis is related to the age of onset, on institution of therapy, and systemic manifestations. Of these patients 50% were functionally normal at the time of follow-up, 25% had mild residual disability and 25% were severely crippled.  相似文献   
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Fossils, molecules, divergence times, and the origin of lissamphibians   总被引:6,自引:0,他引:6  
A review of the paleontological literature shows that the early dates of appearance of Lissamphibia recently inferred from molecular data do not favor an origin of extant amphibians from temnospondyls, contrary to recent claims. A supertree is assembled using new Mesquite modules that allow extinct taxa to be incorporated into a time-calibrated phylogeny with a user-defined geological time scale. The supertree incorporates 223 extinct species of lissamphibians and has a highly significant stratigraphic fit. Some divergences can even be dated with sufficient precision to serve as calibration points in molecular divergence date analyses. Fourteen combinations of minimal branch length settings and 10 random resolutions for each polytomy give much more recent minimal origination times of lissamphibian taxa than recent studies based on a phylogenetic analyses of molecular sequences. Attempts to replicate recent molecular date estimates show that these estimates depend strongly on the choice of calibration points, on the dating method, and on the chosen model of evolution; for instance, the estimate for the date of the origin of Lissamphibia can lie between 351 and 266 Mya. This range of values is generally compatible with our time-calibrated supertree and indicates that there is no unbridgeable gap between dates obtained using the fossil record and those using molecular evidence, contrary to previous suggestions.  相似文献   
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The Third Meeting of the International Society for Phylogenetic Nomenclature (ISPN) convened at Dalhousie University in Halifax, Canada, from 20 to 22 July 2008. In addition to contributed talks, the conference included a progress report on the PhyloCode 'Companion Volume', a discussion of how to complete this book in a timely fashion, a demonstration of the online registration data base (RegNum), plenary talks, and Council and business meetings. Topics discussed at the meeting include problems created by rank-based nomenclature in various eukaryotic taxa, dealing with hybrids in rank-based and phylogenetic nomenclature, phyloinformatics, the choice of names to use when the taxonomic content associated with available names varies, teaching phylogenetic nomenclature, and the application of phylogenetic nomenclature to specific taxa.  相似文献   
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The general aim of our in vitro experiments was to study the role of the metabolic hormones leptin, ghrelin, obestatin and IGF-I and mitogen-activated protein kinase (MAPK)-dependent intracellular mechanisms in the control of nuclear maturation of porcine oocytes. For this purpose, porcine oocytes were isolated from the ovary and cultured in the presence of leptin, ghrelin, obestatin, IGF-I, MAPK blocker PD98059 and the combinations of hormones with PD98059. Proportions of matured oocytes (at metaphase II of meiosis, determined by DAPI staining) and of oocytes containing MAPK/ERK1-2 (determined by immunocytochemistry) were measured before and after culture. It was observed that the majority of oocytes isolated from the ovary before culture were immature and did not contain visible MAPK, but some oocytes were mature, and the majority of these oocytes contained MAPK. Incubation of oocytes resulted in a significant increase in the proportion of matured oocytes and in the percentage of oocytes containing MAPK in both the matured and not matured groups. Addition of IGF-I to the culture medium increased the proportion of matured oocytes, addition of leptin decreased it, and ghrelin and obestatin did not oocyte maturation. Addition of hormones did not affect the expression of MAPK in either immature or mature oocytes. PD98059, when given alone, suppressed the maturation and accumulation of MAPK in both mature and immature oocytes. When given together with hormones, PD98059 was able to reduce the stimulatory effect of IGF-I, to invert the inhibitory action of leptin to stimulatory and to induce the stimulatory action of ghrelin and obestatin on meiosis. IGF-I, ghrelin and obestatin, but not leptin, when given together with PD98059, increased the accumulation of MAPK in both immature and mature oocytes. Association of nuclear maturation and expression of MAPK in oocytes before, but not after culture, as well as the prevention of oocyte maturation by MAPK blocker suggests the involvement of MAPK-dependent intracellular mechanisms in the promotion of reinitiation, but not completion of meiosis. The effect of hormonal additions on meiosis of oocytes suggests that IGF-I is a stimulator, leptin can be an inhibitor, while ghrelin and obestatin probably do not control oocyte maturation. The ability of PD98059 to modify the effect of hormones on oocyte maturation and on MAPK expression suggests possible interference of hormones and MAPK-dependent intracellular mechanisms in oocytes. However, no influence of hormones on MAPK and lack of association between action of hormones and PD98059 on MAPK and meiosis suggest that MAPK is probably not a mediator of effect of IGF-I, leptin, ghrelin and obestatin on porcine oocyte nuclear maturation.  相似文献   
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The anode/electrolyte interface behavior, and by extension, the overall cell performance of sodium-ion batteries is determined by a complex interaction of processes that occur at all components of the electrochemical cell across a wide range of size- and timescales. Single-scale studies may provide incomplete insights, as they cannot capture the full picture of this complex and intertwined behavior. Broad, multiscale studies are essential to elucidate these processes. Within this perspectives article, several analytical and theoretical techniques are introduced, and described how they can be combined to provide a more complete and comprehensive understanding of sodium-ion battery (SIB) performance throughout its lifetime, with a special focus on the interfaces of hard carbon anodes. These methods target various length- and time scales, ranging from micro to nano, from cell level to atomistic structures, and account for a broad spectrum of physical and (electro)chemical characteristics. Specifically, how mass spectrometric, microscopic, spectroscopic, electrochemical, thermodynamic, and physical methods can be employed to obtain the various types of information required to understand battery behavior will be explored. Ways are then discussed how these methods can be coupled together in order to elucidate the multiscale phenomena at the anode interface and develop a holistic understanding of their relationship to overall sodium-ion battery function.  相似文献   
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A study of body size and the compactness profile parameters of the humerus of 37 species of lissamphibians demonstrates a relationship between lifestyle (aquatic, amphibious or terrestrial) and bone microstructure. Multiple linear regressions and variance partitioning with Phylogenetic eigenVector Regressions reveal an ecological and a phylogenetic signal in some body size and compactness profile parameters. Linear discriminant analyses segregate the various lifestyles (aquatic vs. amphibious or terrestrial) with a success rate of up to 89.2%. The models built from data on the humerus discriminate aquatic taxa relatively well from the other taxa. However, like previous models built from data on the radius of amniotes or on the femur of lissamphibians, the new models do not discriminate amphibious taxa from terrestrial taxa on the basis of body size or compactness profile data. To make our inference method accessible, spreadsheets (see supplementary material on the website), which allow anyone to infer a lissamphibian lifestyle solely from body size and bone compactness parameters, were produced. No such easy implementation of habitat inference models is found in earlier papers on this topic.  相似文献   
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The Early Permian mesosaurids are the oldest known aquatic amniotes with an exclusively Gondwanan distribution. Although several hundred of complete skeletons have been discovered and intensively studied, the anatomy and taxonomic composition of the group, as well as its phylogenetic relationships remain controversial. Several well-preserved mesosaurid specimens found in Uruguay justify a new anatomical reconstruction of the skull of Mesosaurus tenuidens, differing from earlier ones especially in the presence of a lower temporal fenestra. The significance of this structure for the evolution of temporal fenestration in amniotes is evaluated according to the two most recent phylogenetic hypotheses, in which mesosaurids are basalmost sauropsids or basalmost parareptiles. A synapsid-like fenestration may be the primitive condition for Amniota, and it may be also a basal condition for parareptiles, because recent phylogenies suggest a basal position for mesosaurids and lanthanosuchoids within that group, and both possess a lower temporal fenestra. Our results also give a moderately strengthened support for diapsid affinities of turtles.  相似文献   
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