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1.
Three groups of 4 cattle have been vaccinated with either detergent solubilized tick tissue proteins (SMP) of male and female Rhipicephalus appendiculatus, a 20 kDa soluble integumental antigen, a mixture of both SMP and 20 kDa. Two weeks after one booster injection all cattle were challenged by infestation with adult ticks. Treatment had no influence on tick attachment but on cattle vaccinated by the 20 kDa 32.5% fed ticks died (p < 0.001). Moreover, the mean weight of ticks fed on 7 out of 12 vaccinated cattle was significantly lower (p < 0.05 to p < 0.001). Individual differences could be seen where the mean weight reduction was up to 30%. Moreover, ticks fed on 1 (group SMP) or 2 cattle (group 20 kDa) had some difficulties in converting their blood meal into eggs (p < 0.05 to p < 0.001).  相似文献   
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Rabbits have been infested 3 times with 10 female and 10 male Ixodes ricinus. Immunity which is induced when ticks feed on naive animals (1st infestation) perturbs feeding, oviposition and embryogenesis during reinfestations. Treatment of rabbits during a 3rd infestation (resistant animals) with cyclosporin A (CsA), an immunosuppressive agent which works on the cellular compartment (chiefly T helper cells), partially reversed the negative effects of the immunity on the biology of the ticks. Conversely, CsA may also directly affect the reproductive processes of ticks. Thus, the weight of the eggs laid and the egg conversion factor of ticks fed on naive treated hosts (1st infestation) were diminished. In addition, the preoviposition was prolonged, and finally failure in oviposition and hatching occurred more frequently.  相似文献   
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Non invasive fetal RhD genotyping, based on polymerase-chain-reaction (PCR), is an accurate and validated technique. It allows a reduction by one-third of anti-D immunoglobulin injections to prevent RhD allo-immunization. In case of maternal anti-D immunization, fetal RhD genotyping allows to focus on RhD positive fetuses only the biologic and sonographic follow-up. The wide use of this technique implies the validation and economic evaluation of a commercial RhD genotyping kit, ready for use in non specialized laboratories.  相似文献   
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OBJECTIVES: To evaluate perinatal management and neurological outcome in a group of infants born with Rhesus fetomaternal allo-immunization. PATIENTS AND METHODS: Between 1 January and 31 December 2005, all newborns admitted to neonatal unit of Rouen tertiary centre for Rhesus hemolytic disease were included in a retrospective study and divided in two groups. The newborns who were treated with intrauterine transfusion are in the group 1 and those who needed only postnatal treatment in the group 2. In each case, were considered antenatal management (ultrasonographic data, middle cerebral artery peak systolic velocity, intrauterine transfusion), postnatal treatment (phototherapy, exchange transfusion, transfusion requirements) and neurological outcome. RESULTS: Among 42 cases of Rhesus allo-immunization observed in six years, 28 newborns (67%) were admitted for neonatal cares. No case of fetal hydrops was noted. But 16/28 (57%) were preterm with a median term of 35 weeks gestation (32-36 weeks). In group 1 of six infants who had received intrauterine transfusion (IUT), only one (17%) needed postnatal exchange transfusion, and all six received one to three blood transfusions after their birth. In group 2 of 22 infants who did not receive IUT, 6/22 (27%) needed postnatal exchange and 18/22 (82%) of them received one to four blood transfusions. Phototherapy duration and albumin requirements were similar in both groups. Three deaths occurred, one due to necrotizing enterocolitis and the other two later on due to sudden infant death and fulminant meningococcemia. Neurological outcome of the remaining 25 children was normal. DISCUSSION AND CONCLUSION: Rhesus alloimmunization remain a situation at risk. Neonatal clinical presentation is less severe than previously described due to improvement in antenatal management. Infants required less postnatal exchange transfusion when they received intrauterine transfusion but more frequent blood transfusions.  相似文献   
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Science literacy is often held up as crucial for avoiding science-related misinformation and enabling more informed individual and collective decision-making. But research has not yet examined whether science literacy actually enables this, nor what skills it would need to encompass to do so. In this report, we address three questions to outline what it should mean to be science literate in today’s world: 1) How should we conceptualize science literacy? 2) How can we achieve this science literacy? and 3) What can we expect science literacy’s most important outcomes to be? If science literacy is to truly enable people to become and stay informed (and avoid being misinformed) on complex science issues, it requires skills that span the “lifecycle” of science information. This includes how the scientific community produces science information, how media repackage and share the information, and how individuals encounter and form opinions on this information. Science literacy, then, is best conceptualized as encompassing three dimensions of literacy spanning the lifecycle: Civic science literacy, digital media science literacy, and cognitive science literacy. Achieving such science literacy, particularly for adults, poses many challenges and will likely require a structural perspective. Digital divides, in particular, are a major structural barrier, and community literacy and building science literacy into media and science communication are promising opportunities. We end with a discussion of what some of the beneficial outcomes could be—and, as importantly, will likely not be—of science literacy that furthers informed and critical engagement with science in democratic society.  相似文献   
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Advances in gene editing technologies for human, plant, and animal applications have led to calls from bench and social scientists, as well as a wide variety of societal stakeholders, for broad public engagement in the decision-making about these new technologies. Unfortunately, there is limited understanding among the groups calling for public engagement on CRISPR and other emerging technologies about 1) the goals of this engagement, 2) the modes of engagement and what we know from systematic social scientific evaluations about their effectiveness, and 3) how to connect the products of these engagement exercises to societal decision or policy making. Addressing all three areas, we systematize common goals, principles, and modalities of public engagement. We evaluate empirically the likely successes of various modalities. Finally, we outline three pathways forward that deserve close attention from the scientific community as we navigate the world of Life 2.0.  相似文献   
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Purpose

To determine the effects of steady-state concentrations of the selective S1P1 receptor modulator ponesimod on the pharmacokinetics (PK) of a single dose of a combined oral contraceptive, containing 1 mg norethisterone (NET) and 35 μg ethinyl estradiol (EE) and to investigate the effects on heart rate at different ponesimod doses within an up-titration regimen prior to co-administration of the contraceptive.

Methods

Twenty-two healthy women (age: 29-60 years) received twice a single oral dose of the combined oral contraceptive, alone or in combination with multiple doses of 40 mg ponesimod attained by an up-titration regimen. Heart rate (HR) effects were assessed on the first day of each up-titration level. PK parameters of NET and EE were determined by non-compartmental analysis.

Results

Geometric mean ratios (ponesimod and contraceptive / contraceptive alone) of Cmax and AUC0-24 of NET were 0.87 (90 % CI: 0.80, 0.94) and 0.84 (90 % CI: 0.76, 0.93), respectively. Geometric mean ratios of Cmax and AUC0-24 of EE were 0.94 (90 % CI: 0.86, 1.03) and 0.95 (90 % CI: 0.89, 1.01), respectively. The maximum mean HR reduction after the first dose of 10 mg ponesimod was 12.4 bpm (SD?±?6.2) at 2.5 h post-dose. On Day 4 (first dose of 20 mg) and Day 7 (first dose of 40 mg) the maximum mean HR reduction was 4.3 bpm (SD?±?5.7) and 1.4 (SD?±?6.4), respectively, at 2.5 h post-dose compared to baseline.

Conclusion

No clinically relevant PK interactions between ponesimod and the combined oral contraceptive were observed, therefore, efficacy of hormonal contraceptives is not expected to be affected by concomitant administration of ponesimod. The up-titration regimen showed that HR reductions are diminished upon repeated ponesimod administration.  相似文献   
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