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131.
以1,4-环己二酮为原料经与哌啶缩合、还原、乙酸汞环合、碱催化分子内缩合等11步反应完成了一叶萩碱的全合成。合成品的熔点及光谱数据与天然一叶萩碱的熔点及光谱数据一致。 相似文献
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Transgenic mice expressing human sickle hemoglobin are partially resistant to rodent malaria 总被引:3,自引:0,他引:3
Shear HL; Roth EF Jr; Fabry ME; Costantini FD; Pachnis A; Hood A; Nagel RL 《Blood》1993,81(1):222-226
The polymorphic frequency of the gene for beta s-globin involved in the generation of sickle trait and sickle cell anemia in the human population is caused by the enhanced resistance of sickle trait individuals to Plasmodium falciparum malaria, as supported by epidemiologic and in vitro studies. However, the mechanism for the protective effect of sickle hemoglobin in vivo has not been fully defined. The generation of transgenic mice expressing high levels of human beta s- and alpha-chains has allowed us to study this phenomenon in vivo in an experimental model. We infected the transgenic beta s mice with two species of rodent malaria and found a diminished and delayed increase in parasitemia as compared with controls. This is in contrast to our previous studies involving the introduction of a beta A transgene, which does not alter the infection. The use of this model allowed us to address the question of the mechanism of protection against malaria in mice expressing sickle hemoglobin. We find that splenectomy of transgenic mice completely reverses the protection against Plasmodium chabaudi adami infection. The results reported have shown a relationship between the presence of the beta s gene product and partial resistance to malaria in an experimental model in vivo and shows that the spleen plays an important role in this protection. 相似文献
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Simon de Lusignan Jamie Lopez Bernal Rachel Byford Gayatri Amirthalingam Filipa Ferreira Oluwafunmi Akinyemi Nick Andrews Helen Campbell Gavin Dabrera Alexandra Deeks Alex J Elliot Else Krajenbrink Harshana Liyanage Dylan McGagh Cecilia Okusi Vaishnavi Parimalanathan Mary Ramsay Gillian Smith Manasa Tripathy John Williams William Victor Maria Zambon Gary Howsam Brian David Nicholson Victoria Tzortziou Brown Christopher C Butler Mark Joy FD Richard Hobbs 《JMIR Public Health and Surveillance》2021,7(2)
BackgroundThe Oxford–Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) and Public Health England (PHE) are commencing their 54th season of collaboration at a time when SARS-CoV-2 infections are likely to be cocirculating with the usual winter infections.ObjectiveThe aim of this study is to conduct surveillance of influenza and other monitored respiratory conditions and to report on vaccine uptake and effectiveness using nationally representative surveillance data extracted from primary care computerized medical records systems. We also aim to have general practices collect virology and serology specimens and to participate in trials and other interventional research.MethodsThe RCGP RSC network comprises over 1700 general practices in England and Wales. We will extract pseudonymized data twice weekly and are migrating to a system of daily extracts. First, we will collect pseudonymized, routine, coded clinical data for the surveillance of monitored and unexpected conditions; data on vaccine exposure and adverse events of interest; and data on approved research study outcomes. Second, we will provide dashboards to give general practices feedback about levels of care and data quality, as compared to other network practices. We will focus on collecting data on influenza-like illness, upper and lower respiratory tract infections, and suspected COVID-19. Third, approximately 300 practices will participate in the 2020-2021 virology and serology surveillance; this will include responsive surveillance and long-term follow-up of previous SARS-CoV-2 infections. Fourth, member practices will be able to recruit volunteer patients to trials, including early interventions to improve COVID-19 outcomes and point-of-care testing. Lastly, the legal basis for our surveillance with PHE is Regulation 3 of the Health Service (Control of Patient Information) Regulations 2002; other studies require appropriate ethical approval.ResultsThe RCGP RSC network has tripled in size; there were previously 100 virology practices and 500 practices overall in the network and we now have 322 and 1724, respectively. The Oxford–RCGP Clinical Informatics Digital Hub (ORCHID) secure networks enable the daily analysis of the extended network; currently, 1076 practices are uploaded. We are implementing a central swab distribution system for patients self-swabbing at home in addition to in-practice sampling. We have converted all our primary care coding to Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT) coding. Throughout spring and summer 2020, the network has continued to collect specimens in preparation for the winter or for any second wave of COVID-19 cases. We have collected 5404 swabs and detected 623 cases of COVID-19 through extended virological sampling, and 19,341 samples have been collected for serology. This shows our preparedness for the winter season.ConclusionsThe COVID-19 pandemic has been associated with a groundswell of general practices joining our network. It has also created a permissive environment in which we have developed the capacity and capability of the national primary care surveillance systems and our unique public health institute, the RCGP and University of Oxford collaboration. 相似文献