| Id |
Subject |
Object |
Predicate |
Lexical cue |
| T29 |
0-144 |
Sentence |
denotes |
Using a live attenuated or inactivated vaccine is typically considered to be the most cost-effective means of controlling viral infections [14]. |
| T30 |
145-495 |
Sentence |
denotes |
Unfortunately, inactivated IB vaccines are not effective if used alone, which could induce little or no protection against egg loss [15], [16], as well as impaired ciliary activity in the trachea [17]; thus, birds must continue to be given one or a series of vaccinations with live attenuated IB vaccines to provide broad heterologous protection [1]. |
| T31 |
496-855 |
Sentence |
denotes |
Commercial attenuated live vaccines used against IBV in China include the H120, LDT3, and 4/91 strains [7]; however, phylogenetic analysis indicates that the QX-like genotype is genetically distant from the strains described above, which may explain the poor cross-protectivity against infection in chickens immunized with these classical vaccines [18], [19]. |
| T32 |
856-961 |
Sentence |
denotes |
Recently, there has been increasing research on live attenuated vaccines against the QX-like IBV strains. |
| T33 |
962-1220 |
Sentence |
denotes |
Different strains of QX-like IBVs were serially passaged in embryonated eggs or primary chicken kidney cells (CK) to obtain vaccines that are less virulent and exhibit high immunogenicity against the QX-like epidemic IBV strains [20], [21], [22], [23], [24]. |
| T34 |
1221-1498 |
Sentence |
denotes |
However, in addition to causing tissue damage or secondary bacterial infections in young vaccinated chicks [25], [26], live attenuated vaccines of RNA viruses may not be genetically stable or they may be associated with the tendency to revert back to a virulent form [9], [14]. |
| T35 |
1499-1630 |
Sentence |
denotes |
Moreover, the potential for recombination between vaccine and virulent strains can lead to the creation of new virulent virus [27]. |
| T36 |
1631-1879 |
Sentence |
denotes |
Furthermore, it takes a substantial amount of time to prepare a extensively passaged attenuated vaccine strain, which may not be able to effectively solved the loss problem caused by the rapid variation exhibited by prevalent strains on the flocks. |
