In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.

Q: BALB/c male mice were mated with either Swiss-Webster or MF1 females to produce first generation cross-bred offspring. Hybridoma cell lines, from the fusion of P3-NS1-Ag4/1 myeloma cells with spleen cells sensitised to the porcine coronavirus causing transmissible gastroenteritis, were injected intraperitoneally into these mice to produce ascitic fluid containing monoclonal antibodies. Mice of 11 weeks of age weighing between 26 and 34 g were used. The volume of ascites produced by mice injected with four of the five hybrid cell lines tested was greater in the cross-bred offspring than in the BALB/c parent. The fifth cell line gave comparable volumes in the MF1 cross-breed and BALB/c parent but a lesser volume in the Swiss-Webster cross-breed. The antibody titres of the ascites as determined by virus neutralisation, radioimmune and indirect immune fluorescence assays, did not differ significantly between mouse types. The ability to use all offspring from a litter of cross-bred mice, irrespective of sex, and the increased volume of ascitic fluid formed in each mouse, permits fewer animals to be used for the production of ascites in these strains, thereby offering considerable economic and ethical advantages over the use of BALB/c mice.

A: Comparison of ascites production for monoclonal antibodies in BALB/c and BALB/c-derived cross-bred mice
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Q: Ten strains of avian infectious bronchitis virus (IBV) were titrated as plaqueforming units in primary chick embryo fibroblast cells. In the absence of trypsin, plaques were only formed by Beaudette-42 and Iowa-609 strains. When trypsin was incorporated in the overlay medium of cell monolayers, all the IBV strains tested produced plaques within 4days after inoculation. Incorporation of 20--40 ~xg of trypsin per ml of the overlay medium seemed to be suitable for plaque formation of IBV. A preliminary investigation was made of the mode of action of trypsin.

A: Archives of Virology Plaque Formation by Avian Infectious Bronehitis Virus in Primary Chick Embryo Fibroblast Cells in the Presence of Trypsin
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Q: A pattern in which nucleotide transitions are favored several fold over transversions is common in molecular evolution. When this pattern occurs among amino acid replacements, explanations often invoke an effect of selection, on the grounds that transitions are more conservative in their effects on proteins. However, the underlying hypothesis of conservative transitions has never been tested directly. Here we assess support for this hypothesis using direct evidence: the fitness effects of mutations in actual proteins measured via individual or paired growth experiments. We assembled data from 8 published studies, ranging in size from 24 to 757 single-nucleotide mutations that change an amino acid. Every study has the statistical power to reveal significant effects of amino acid exchangeability, and most studies have the power to discern a binary conservative-vs-radical distinction. However, only one study suggests that transitions are significantly more conservative than transversions. In the combined set of 1,239 replacements (544 transitions, 695 transversions), the chance that a transition is more conservative than a transversion is 53 % (95 % confidence interval 50 to 56) compared with the null expectation of 50 %. We show that this effect is not large compared with that of most biochemical factors, and is not large enough to explain the several-fold bias observed in evolution. In short, the available data have the power to verify the "conservative transitions" hypothesis if true, but suggest instead that selection on proteins plays at best a minor role in the observed bias.

A:
Article Fast Track On the Causes of Evolutionary Transition:Transversion Bias
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