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51.
《Vaccine》2020,38(6):1526-1534
Despite decades of vaccination, surveillance, and biosecurity measures, H5N2 low pathogenicity avian influenza (LPAI) virus infections continue in Mexico and neighboring countries. One explanation for tenacity of H5N2 LPAI in Mexico is the antigenic divergence of circulating field viruses compared to licensed vaccines due to antigenic drift. Our phylogenetic analysis indicates that the H5N2 LPAI viruses circulating in Mexico and neighboring countries since 1994 have undergone antigenic drift away from vaccine seed strains. Here we evaluated the efficacy of a new recombinant fowlpox virus vector containing an updated H5 insert (rFPV-H5/2016), more relevant to the current strains circulating in Mexico. We tested the vaccine efficacy against a closely related subcluster 4 Mexican H5N2 LPAI (2010 H5/LP) virus and the historic H5N2 HPAI (1995 H5/HP) virus in White Leghorn chickens. The rFPV-H5/2016 vaccine provided hemagglutinin inhibition (HI) titers pre-challenge against viral antigens from both challenge viruses in almost 100% of the immunized birds, with no differences in number of birds seroconverting or HI titers among all tested doses (1.5, 2.0, and 3.1 log10 mean tissue culture infectious doses/bird). The vaccine conferred 100% clinical protection and a significant decrease in oral and cloacal virus shedding from 1995 H5/HP virus challenged birds when compared to the sham controls at all tested doses. Virus shedding titers from vaccinated 2010 H5/LP virus challenged birds significantly decreased compared to sham birds especially at earlier time points. Our results confirm the efficacy of the new rFPV-H5/2016 against antigenic drift of LPAI virus in Mexico and suggest that this vaccine would be a good candidate, likely as a primer in a prime-boost vaccination program. 相似文献
52.
Dov Fox 《The Hastings Center report》2020,50(2):13-15
During the 2016 election, Donald Trump won conservative support by promising that he would, if elected, nominate “pro-life” justices to the U.S. Supreme Court. Whether President Trump makes good on his campaign promise to restrict abortion rights may come down to competing impulses of the chief justice, John Roberts. These dueling dispositions—from the man whom many see as the new “swing justice”—hold the key to a blockbuster new case that legal historians call “the most unpredictable the Supreme Court has been on abortion in decades.” The case, June Medical Services v. Russo, turns on arduous new requirements that Louisiana has imposed on facilities and clinicians that provide abortion. But the case is not just about abortion access. The Court will have to decide whether a clinic has a right to challenge the law in the first place. 相似文献
53.
目的研究海南地不容(Stephania hainanensis H.S.Lo et Y.Tsoong)生物碱对人肝癌细胞Hep G-2、乳腺癌细胞MCF-7、胃癌细胞SGC-7901增殖的影响,筛选出有效的抗肿瘤化合物以及其敏感细胞株;分析其生物碱的构效关系。方法采用MTT法检测不同浓度的海南地不容生物碱对人肝癌细胞Hep G-2、乳腺癌细胞MCF-7、胃癌细胞SGC-7901增殖的抑制率;通过查阅国内外相关文献,分析海南地不容生物碱抗肿瘤活性的基本构效关系。结果MTT结果显示荷包牡丹碱、氧化克班宁、去甲荷包牡丹碱和克班宁对人肝癌Hep G-2、乳腺癌MCF-7和胃癌SGC-7901细胞的增值分别具有不同程度的剂量依赖性的抑制作用,各给药组分吸光度值与空白对照组比具有显著性差异(P<0.01),与阳性对照比较无明显统计学差异(P>0.05);海南地不容生物碱结构中的1,2-亚甲二氧基、N-亚甲基等取代基以及其化学结构的平面性对其抗肿瘤活性有重要影响。结论海南地不容中具有明显抗肿瘤作用的生物碱为荷包牡丹碱、氧化克班宁、去甲荷包牡丹碱和克班宁,其敏感细胞株均为乳腺癌细胞MCF-7;通过分析海南地不容生物碱的结构和抗肿瘤活性的关系,初步明确了其抗肿瘤活性可能与其结构易于抑制DNA拓扑异构酶和诱导细胞凋亡有关。 相似文献
54.
《Journal of the American Medical Directors Association》2020,21(3):439.e9-439.e13
Background/ObjectivesPolypharmacy and multimorbidity is a threat to older people; hence, listing approaches should support physicians to optimize medication. The FORTA (Fit fOR The Aged) classification of drug appropriateness for older people provides positive or negative labels: A (A-bsolutely), B (B-eneficial), C (C-areful), and D (D-on't). Based on these categories, FORTA-labeled drug lists were developed in 7 European countries or regions; the same approach was used to develop a U.S.-FORTA List reflecting the country-specific availability and usage of drugs.Design/SettingA 2-step Delphi-type approach was employed to add, remove, or relabel drugs from the listing proposal and to add or remove new indications. The proposal utilized the European (EURO)-FORTA list as template.ParticipantsEight US-based geriatricians/pharmacists served as raters. Measurements: Raters gave recommendations and comments on the list items.ResultsThe first U.S.-FORTA List contains 273 items aligned to 27 main indication groups; 30 drugs and drug groups were added, and 23 removed as being unavailable in the United States. The highest percentage of changes in FORTA labels as compared to the EURO-FORTA List occurred for sleep disorders associated with dementia (40%). In 8 indications, the labels for 11 items were different from the proposal. Thus, for the majority of the items (n = 232, 95.5%), the proposals were accepted by the US raters. Only 16 (6.6%) of the proposed items (n = 243) had to be re-evaluated in the second round as a result of inconsistent rating in the first round.Conclusions and ImplicationsThe U.S.-FORTA List addresses the appropriateness of drugs for older people in the United States reflecting country-specific availability, usage, and expert rating. As shown for the FORTA list in Europe, this listing approach is among the few that are clinically validated and improve well-being and geriatric outcomes. The U.S.-FORTA List now largely enhances the global availability of this approach. 相似文献
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58.
目的:探讨D6S1043、D12S391基因座的基因多态性对主动攻击行为的影响。方法:应用聚合酶链反应技术结合毛细管电泳法对114例男性主动攻击行为者(研究组)及120名健康男性(对照组)进行D6S1043、D12S391基因座的基因型及等位基因检测,分析D6S1043、D12S391基因座多态性与主动攻击行为的相关性。结果:研究组D6S1043基因座中12~19基因型频率(13.16%)明显高于对照组(1.67%)(P0.05);两组等位基因频率差异无统计学意义;两组D12S391基因座的基因型及等位基因频率差异无统计学意义。结论:D6S1043基因座中12~19基因型可能主动攻击行为有关。 相似文献
59.
Ahmet Basaran ?zgür Deren Yahya Buyukasik Mustafa Basaran 《Indian journal of hematology & blood transfusion》2015,31(2):286-291
We carried out a retrospective cohort study to construct reference ranges for free protein S (FPS) levels during pregnancy and identify any conditions or factors that may affect FPS levels. Patients that were ordered thrombophilia screening tests during gestational period were identified. Patients demonstrated to have hereditary or acquired thrombophilia were excluded. Reference ranges were constructed using regression analysis. Outcome of the index pregnancy and pregnancy complications was used to identify any confounding factors. A total of 455 pregnant women were included. The quadratic equation for FPS according to gestational age (GA) was [75.497 + (−1.516*GA) + 0.018*GA*GA]. FPS level and GA were negatively correlated (Spearmans rho statistic [rs] = −0.436, p = 0.001). FPS level and fetal growth restriction (FGR) were negatively correlated ([rs] = −0.093, p = 0.049). FPS level and placental abruption were positively correlated ([rs] = 0.098, p = 0.039). Stepwise linear regression model constructed to predict FPS level with gestational age, placental abruption and FGR as the predictor variables. Gestational age was the only variable retaining statistically significant relation with FPS level (χ2 = 0.216, df = 3, p = 0.001). FPS levels decrease significantly throughout gestation in gravidas without hereditary and/or acquired thrombophilias. In patients without thrombophilia FPS levels are not associated with pregnancy complications. The obtained reference intervals may be useful for the clinicians ordering FPS during pregnancy. 相似文献
60.
This is the first Japanese autopsy case of Leucine-rich repeat kinase 2 (LRRK2) G2019S mutation with atypical TDP43 proteinopathy. Our case is important that presented clinically dysphagia and pathologically TDP-43 proteinopathy. TDP43 may play an important role of clinical presentation with LRRK2 G2019S mutation carriers. 相似文献