Viras

J Arasena-A (Mochida) Vitarabine (Ajinomoto) USA Vira-A (Parke Davis) wfm... 

Fig. 4 The influenza A viras sialidase active site showing some key interactions...

Scheme 1 The reaction catalyzed by influenza viras sialidase. The initially formed a-anomer 3a undergoes rapid equilibration with the 3-anomer 3b...

Avoid the use of tobacco if you grow tomatoes, peppers or Irish potatoes. Tobacco coutaius tobacco mosaic viras (TMV) which will get ou your hands and be spread to plants which you touch. Equipment, insects or anything touching an infested plant and then another plant is also likely to transfer the disease from plant to plant. TMV is very hard to control and reduces both fruit set and fmit size. Total yield of TMV-infested plants may be reduced slightly or nearly wiped out. Leaves of infested plants may be distorted and will probably have a mottled appearance rather than a solid green color. Remove isolated plants showing these symptoms as soon as they appear. 

Vidarabine (adenine arabinoside, Vira-A) is an adenine nucleoside analogue containing arabinose in place of ri-bose. It is obtained from cultures of Streptomyces an-tibioticus and has activity against HSV-1, HSV-2, VZV, CMV, HBV, poxviruses, hepadnaviruses, rhabdoviruses, and certain RNA tumor viruses. 

Antiviral mostly used against herpes simplex vims (HSVl and 2) and varicella-zoster viras (VZV). 

Pseudognaphalium cheiranthifolium, P. vira vira Asterac. Leaf trichome 337... 

Urzua, A. et al., Flavonoids and diterpenoids in the trichome resinous exudates from Pseudogna-phalium cheiranthifolium, P. heterotrichium and P. vira vira, Biochem. Syst. Ecol, 23, 459, 1995. 

Furthermore, a number of studies have shown that the direct mutagenicity of particles is primarily associated with particles having Dp < 2.5 /tm. For example, Viras and co-workers (1990) report that at two sites in Athens, Greece, 81 and 92% of the total direct activities (TA98 — S9) were associated with particles having Dp < 3.3 /r,m. Furthermore, 60 and 80%, respectively, were in submicron particles, Dp <1.0 gm. 

During wintertime, in most urban areas, mutagenicity levels are generally higher than during the summer. For example, Fig. 10.18 shows the results of Viras and co-workers (1990) for 24-h average mutagenicities (rev... 

FIGURE 10.18 Seasonal variation in the mutagen density (rev m-3, TA98, —S9) of extracts of ambient particles, and the associated BaP levels (ng m 3), collected at four sites in Athens, Greece, February 1984-January 1985. The annual average was 1.9 rev m-3 (adapted from Viras et al., 1990). 

Viras, L. G., K. Athanasiou, and P. A. Siskos, Determination of Mutagenic Activity of Airborne Particulates and of the Bcnzo[u]pyrene Concentrations in Athens Atmosphere, Atmos. Environ., 24B, 267-274 (1990). 

Rappengliick, P. Fabian, P. Kalabokas, L. G. Viras, and I. C. Ziomas, Quasi-Continuous Measurements of Non-Methane Hydrocarbons (NMHC) in the Greater Athens Area during Medcaphot-Trace, Atmos. Environ., 32, 2103-2121 (1998). 

VirG Works in conjunction with VirA, activates vir gene expression... 

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