To elucidate the relationship between Epstein-Barr virus (EBV) and rheumatoid arthritis (RA), we measured antibodies to RA-associated nuclear antigen (anti-RANA) and three other EBV-related antigens in the sera of RA patients and controls. Our study groups consisted of 89 patients with definite or classical RA, mean age 56, male/female ratio 47:42; and 53 normal and osteoarthritis controls, mea...

pipiens complex, were analyzed for morphological differentiation using multivariate techniques. Field-collected and laboratory-reared larvae of both species were compared for 12 morphometric characters. R. berlandieri larvae differ from R. sphenocephala larvae in having a more fusiform body shape, greater tail musculature development, a longer tail, relatively narrow dorsal and ventral tail fin...

The effect of the emerging omicron variant on willingness to take or continue with COVID-19 vaccination in Middle EastTareq L. Mukattash, Anan S. Jarab, Rana K. Abu-Farha, Rania Itani, Samar Karout, Razan Z. Mansour, Shorouq Abuhishmah

Antibodies against chicken and Torpedo agrin were used for immunofluorescent staining in order to assess the spatial distribution and temporal appearance of agrin-like molecules at newly formed synaptic contacts in cultures of embryonic Xenopus nerve and muscle cells. The antibodies stained Xenopus neuromuscular junctions and removed ACh receptor (AChR)-aggregating activity from extracts of Xen...

W A D D I N G T O N (1935) and later Needham (1936) have suggested that the autonomy of tumours originates in a 'morphological escape' of tumour cells from the controlling influence of an individuation field which has locally become weak or has vanished. The persistence and strength of such an individuation field can be seen in its ability to induce its parts to regeneration (Ruben, 1955). This...

The kinematics of swimming in tadpoles from four species of anurans (Rana catesbeiana Shaw, Rana septentrionalis Baird, Rana clamitans Latreille and Bufo americanus Holbrook) was studied using computerassisted analysis of high speed (^200 frames s") cine" records. 1. Tadpoles exhibit the same positive, linear relationship between tail beat frequency and specific swimming speed commonly reported...

Some territorial animals display low levels of aggression towards a familiar territorial neighbour in its usual territory, but exhibit high levels of aggression towards neighbours in novel locations and unfamiliar individuals. Here, we report results from a field playback study that investigated whether territorial males of the North American bullfrog (Rana catesbeiana) could discriminate betwe...