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J Bordas R C Bray C D Garner S Gutteridge S S Hasnain 《Journal of inorganic biochemistry》1979,11(2):181-186
EXAFS spectra associated with the K-absorption edge of molybdenum in the desulpho and functional forms of xanthine oxidase and some potential synthetic analogues have been obtained. These data indicate that the immediate environment of the molybdenum is different in the two forms of the enzyme and that desulpho xanthine oxidase resembles that in [MoO2(S2CNEt2)2] and [MoO2(ethylcysteine)2]. The cyanolysable sulphur atom of functional xanthine oxidase is suggested to be tightly bound to the molybdenum at a distance of less than or equal to 2.3 A. 相似文献
966.
Anand Krishnan Lalit Dar Siddhartha Saha Venkatesh Vinayak Narayan Rakesh Kumar Ramesh Kumar Ritvik Amarchand Shivram Dhakad Reshmi Chokker Avinash Choudekar Giridara Gopal Aashish Choudhary Varsha Potdar Mandeep Chadha Kathryn E. Lafond Stephen Lindstrom Marc-Alain Widdowson Seema Jain 《PLoS medicine》2021,18(4)
BackgroundInfluenza is a cause of febrile acute respiratory infection (FARI) in India; however, few influenza vaccine trials have been conducted in India. We assessed absolute and relative efficacy of live attenuated influenza vaccine (LAIV) and inactivated influenza vaccine (IIV) among children aged 2 to 10 years in rural India through a randomized, triple-blind, placebo-controlled trial conducted over 2 years.Methods and findingsIn June 2015, children were randomly allocated to LAIV, IIV, intranasal placebo, or inactivated polio vaccine (IPV) in a 2:2:1:1 ratio. In June 2016, vaccination was repeated per original allocation. Overall, 3,041 children received LAIV (n = 1,015), IIV (n = 1,010), nasal placebo (n = 507), or IPV (n = 509). Mean age of children was 6.5 years with 20% aged 9 to 10 years.Through weekly home visits, nasal and throat swabs were collected from children with FARI and tested for influenza virus by polymerase chain reaction. The primary outcome was laboratory-confirmed influenza-associated FARI; vaccine efficacy (VE) was calculated using modified intention-to-treat (mITT) analysis by Cox proportional hazards model (PH) for each year.In Year 1, VE was 40.0% (95% confidence interval (CI) 25.2 to 51.9) for LAIV and 59.0% (95% CI 47.8 to 67.9) for IIV compared with controls; relative efficacy of LAIV compared with IIV was −46.2% (95% CI −88.9 to −13.1). In Year 2, VE was 51.9% (95% CI 42.0 to 60.1) for LAIV and 49.9% (95% CI 39.2 to 58.7) for IIV; relative efficacy of LAIV compared with IIV was 4.2% (95% CI −19.9 to 23.5). No serious adverse vaccine-attributable events were reported. Study limitations include differing dosage requirements for children between nasal and injectable vaccines (single dose of LAIV versus 2 doses of IIV) in Year 1 and the fact that immunogenicity studies were not conducted.ConclusionsIn this study, we found that LAIV and IIV vaccines were safe and moderately efficacious against influenza virus infection among Indian children.Trial registrationClinical Trials Registry of India CTRI/2015/06/005902.Anand Krishnan and co-workers study the efficacy and safety of influenza vaccines for children in India. 相似文献
967.
The derivation of the restricted intra-sire regression heritability estimator is provided. Procedures for obtaining a stable estimate of residual error variance σ2 are outlined. A small illustration based on live data is given. 相似文献
968.
Expression of the gene encoding firefly luciferase in insect cells using a baculovirus vector 总被引:1,自引:0,他引:1
A cDNA encoding the firefly luciferase [Photinus luciferin: oxygen 4-oxidoreductase (decarboxylating, ATP-hydrolyzing), EC 1.13.12.7] was cloned downstream from the polyhedrin gene promoter of Autographa californica nuclear polyhedrosis virus and expressed in Spodoptera frugiperda clone-9 cells. Synthesis of luciferase (Luc) was accurately measured in insect cells growing in a 96-well plate, by a simple, rapid, nonradioactive, inexpensive and sensitive method based on fogging of x-ray film. Luc was produced in a coordinate fashion during virus infection. The Luc synthesized in insect cells was not secreted into the medium but was contained within the cell. Our findings suggest that Luc can be used as a superior reporter enzyme for molecular genetic analyses of baculovirus regulatory signals involved in high level expression of foreign genes, protein processing, targeting and stability in insect cells. 相似文献