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Leek JT  Taub MA  Pineda FJ 《PloS one》2011,6(11):e26895
Peer review is fundamentally a cooperative process between scientists in a community who agree to review each other''s work in an unbiased fashion. Peer review is the foundation for decisions concerning publication in journals, awarding of grants, and academic promotion. Here we perform a laboratory study of open and closed peer review based on an online game. We show that when reviewer behavior was made public under open review, reviewers were rewarded for refereeing and formed significantly more cooperative interactions (13% increase in cooperation, P = 0.018). We also show that referees and authors who participated in cooperative interactions had an 11% higher reviewing accuracy rate (P = 0.016). Our results suggest that increasing cooperation in the peer review process can lead to a decreased risk of reviewing errors.  相似文献   
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Measurements from microarrays and other high-throughput technologies are susceptible to non-biological artifacts like batch effects. It is known that batch effects can alter or obscure the set of significant results and biological conclusions in high-throughput studies. Here we examine the impact of batch effects on predictors built from genomic technologies. To investigate batch effects, we collected publicly available gene expression measurements with known outcomes, and estimated batches using date. Using these data we show (1) the impact of batch effects on prediction depends on the correlation between outcome and batch in the training data, and (2) removing expression measurements most affected by batch before building predictors may improve the accuracy of those predictors. These results suggest that (1) training sets should be designed to minimize correlation between batches and outcome, and (2) methods for identifying batch-affected probes should be developed to improve prediction results for studies with high correlation between batches and outcome.  相似文献   
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Sporocysts of Sarcocystis suihominis obtained from human feces were used to infect swine. Heart, tongue, and skeletal muscle from experimentally infected and noninfected control swine were fed via stomach tube to nonhuman primates including chimpanzees (Pan troglodytes), rhesus monkeys (Macaca mulatta), and cynomolgus monkeys (Macaca irus). All primates fed infected swine tissues shed sporocysts beginning 13 to 15 days postinfection and were still shedding sporocysts at the conclusion of the experiment, 30 days postinfection. Rhesus and cynomolgus monkeys were fed infected swine tissues a second time and shed sporocysts. All primates remained in good health throughout both experiments and exhibited no unusual clinical signs as a result of infection.  相似文献   
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Transferrin, a glycoprotein involved in iron transport in body fluids, was isolated from amniotic fluid of a hydramniospatient by sequential anion-exchange chromatography and gel filtration. The N-glycans of human amniotic fluid transferrin (hAFT) were enzymatically liberated by PNGase-F digestion, isolated by gel filtration and fractionated by (high-pH) anion-exchange chromatography. After alkaline borohydride treatment of native hAFT, the released O-glycans were isolated by gel filtration and fractionated by anion-exchange chroma-tography. Structure elucidation of 14 N- and 2 O-glycans was performed by 500 or 600 MHz1H-NMR spectroscopy. Besides conventional N-glycans established earlier for human serum transferrin (hST), new (alpha1-3)-fucosylated N- glycans were found, representing sialyl Le(x) elements. Furthermore, as compared to hST, a higher degree of (alpha1-6)-fucosylation and an increase in branching from di- to triantennary compounds has been detected. The presence of O-glycans is demonstrated for the first time in transferrin.   相似文献   
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The mechanism of uterine muscle contraction stimulated by a triterpenoid glycoside (dalsaxin) isolated from the root of D. saxatilis was investigated by in vitro methods in the rat. Dalsaxin caused a dose-related increase in uterine muscle contraction. The contraction was single and transient and was abolished by moderate doses of isoprenaline (1.80 nmol-0.40 mumol) and salbutamol (0.13-25 mumol). Adrenaline (9.10 nmol) also caused a reversible decrease (92.6%; P < 0.01) in myometrial contraction stimulated by this glycoside (0.24 mg/ml). Uterine muscle responses to dalsaxin (0.24 mg/ml) were enhanced by the beta-adrenergic receptor antagonist, propranolol, in a dose related manner. Atipamezole (1.50 ng/ml) but not prazosin (7.72 nmol-15.60 nmol) substantially reduced (80%; P < 0.01) myometrial contractions induced by this uterine spasmogen. The results suggest that dalsaxin enhances uterine muscle contraction by stimulating post junctional alpha 2-adrenergic receptors, presumably by inhibiting plasma membrane adenylate cyclase system and its associated increase in intracellular cAMP content.  相似文献   
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