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Balanced chromosome rearrangements were found in seven of 455 retarded children vs. four of 1,679 nonretarded, psychiatric children (P less than .05). The combined incidence of non-Robertsonian balanced rearrangements from this and reported surveys of the mentally retarded was five times greater than that from newborn surveys, whereas Robertsonian translocations were not increased among the retarded. The combined data show an increase in de novo rather than familial rearrangements among the retarded; the increase in de novo rearrangements is specifically for non-Robertsonian translocation.  相似文献   
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This report describes an infant with fatal congenital heart disease, cleft palate, brain malformations, and trisomy 8p resultant from the paternal balanced reciprocal translocation, rcp(8;15) (p11;p11). Review of six previously reported trisomy 8p patients (resultant from parental balanced translocation in each instance) revealed severe mental retardation in five, short stature in all, and a variety of brain, skeletal, and cardiac defects. The features of the seven trisomy 8p patients reviewed here are not sufficiently similar to suggest a distinct dysmorphic syndrome. In addition the features differ from those in the trisomy 8 mosaicism syndrome, in which the mental retardation and malformations are generally less severe.  相似文献   
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Three subjects performed five successive isometric contractions to fatigue; the tension in any one experiment was constant at tensions varying from 20 to 80% of the maximal voluntary contraction (MVC). The interval between contractions was held constant at 11 min. Muscle biopsy specimens were obtained at the start of the experiment, after the first, fourth, and fifth, and before the second and fifth of the successive contractions. The concentrations of ATP, CP, glycogen, and lactate were measured in each sample of muscle. Changes in ATP and glycogen were insufficient to be held accountable for the development of isometric fatigue. Changes in CP and lactate were large after fatigue at intermediate tensions, but those of CP were considered unlikely to be responsible for the fatigue. At tensions of 30-50% MVC the increase in lactate could be responsible for fatigue either directly or by indirect changes in pH; at higher and lower tensions the possibility that lactate is directly implicated in the development of fatigue seems remote.  相似文献   
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Invasive arthropods pose unique management challenges in various environments, the first of which is correct identification. This apparently mundane task is particularly difficult if multiple species are morphologically indistinguishable but accurate identification can be determined with DNA barcoding provided an adequate reference set is available. Scirtothrips dorsalis is a highly polyphagous plant pest with a rapidly expanding global distribution and this species, as currently recognized, may be comprised of cryptic species. Here we report the development of a comprehensive DNA barcode library for S. dorsalis and seven nuclear markers via next-generation sequencing for identification use within the complex. We also report the delimitation of nine cryptic species and two morphologically distinguishable species comprising the S. dorsalis species complex using histogram analysis of DNA barcodes, Bayesian phylogenetics, and the multi-species coalescent. One member of the complex, here designated the South Asia 1 cryptic species, is highly invasive, polyphagous, and likely the species implicated in tospovirus transmission. Two other species, South Asia 2, and East Asia 1 are also highly polyphagous and appear to be at an earlier stage of global invasion. The remaining members of the complex are regionally endemic, varying in their pest status and degree of polyphagy. In addition to patterns of invasion and endemism, our results provide a framework both for identifying members of the complex based on their DNA barcode, and for future species delimiting efforts.  相似文献   
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Background

Whether inhaled corticosteroids suppress airway inflammation in chronic obstructive pulmonary disease (COPD) remains controversial. We sought to determine the effects of inhaled corticosteroids on sputum indices of inflammation in stable COPD.

Methods

We searched MEDLINE, EMBASE, CINAHL, and the Cochrane Databases for randomized, controlled clinical trials that used induced sputum to evaluate the effect of inhaled corticosteroids in stable COPD. For each chosen study, we calculated the mean differences in the concentrations of sputum cells before and after treatment in both intervention and control groups. These values were then converted into standardized mean differences to accommodate the differences in patient selection, clinical treatment, and biochemical procedures that were employed across original studies. If significant heterogeneity was present (p < 0.10), then a random effects model was used to pool the original data. In the absence of significant heterogeneity, a fixed effects model was used.

Results

We identified six original studies that met the inclusion criteria (N = 162 participants). In studies with higher cumulative dose (≥ 60 mg) or longer duration of therapy (≥ 6 weeks), inhaled corticosteroids were uniformly effective in reducing the total cell, neutrophil, and lymphocyte counts. In contrast, studies with lower cumulative dose (< 60 mg) or shorter duration of therapy (< 6 weeks) did not demonstrate a favorable effect of inhaled corticosteroids on these sputum indices.

Conclusions

Our study suggests that prolonged therapy with inhaled corticosteroids is effective in reducing airway inflammation in stable COPD.  相似文献   
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In addition to its implication in the virulence of Streptococcus pyogenes, the hyaluronic acid capsule produced by this bacterium renders it resistant to infection by bacteriophage. A method employing S. pyogenes and a bacteriophage incorporated into an agar plate was devised as a screen to detect compounds that inhibit the formation of the hyaluronic acid capsule. Filter-paper discs saturated with experimental compounds were applied to the surface of test plates containing host plus phage and control plates of host only. After incubation, inhibition of capsule synthesis was indicated by the presence of clear zones where phage infection and lysis had occurred. Zones of growth inhibition on control plates represented classical antibacterial activity. During the testing of over 6,000 fermentation samples, anticapsin, a unique metabolite, was discovered. Modification of incubation temperature, thickness of agar layers, and host-phage input ratios resulted in a quantitative assay method having a dose-response range of 4 to 160 μg of anticapsin.  相似文献   
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