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991.
A report is given of the results obtained by intratesticular inoculation of a malignant tumor of the rabbit based on a study of the first twenty generations. The subject is presented from the standpoint of variations in growth and malignancy as they occurred with continued transplantation. Essential features of the experimental conditions and of clinical and postmortem observations are condensed and recorded graphically. On analyzing the results of these experiments, it was found that many changes had occurred in the behavior of the tumor during transplantation, but that the changes were of a very irregular character and as a rule did not proceed constantly in any given direction. Moreover, the evidence as to the effect of transplantation on the growth and malignancy of the tumor was contradictory in that there was a great deal of evidence to show that there had been a decided increase in the activity and capacity for growth on the part of the tumor cells. But, with the exception of a few generations, there was an apparent reduction in the incidence and percentage distribution of secondary tumors, while the death rate was unaltered or actually diminished. It was believed that this paradoxical situation afforded a basis for an explanation of the results that had been obtained by transplantation.  相似文献   
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Fish is a good animal-source protein for growth and development. The main objective of the study was to assess the efficacy of fish during the early complementary feeding period on infants’ linear growth in the Samfya district of the Luapula Province of Zambia in 6 months randomised controlled trial. The study was conducted from April 2019 to January 2020. Infants aged 6–7 months (N = 238) were assigned to either the intervention (treatment) group or control (placebo) group to receive fish powder or sorghum powder, respectively. Participants were followed on a weekly basis to distribute the powder and record compliance/usage and any morbidities. Anthropometric measurements were taken monthly. A linear mixed-effects model showed that fish powder improved linear growth among infants over all the 6 months of the intervention period. The fish powder increased length-for-age z scores by 1.26 (95% CI: 0.94–1.57) and weight-for-age z score by 0.95 (95% CI 0.6–1.23). The addition of fish powder to the infant’s usual food during the early complementary feeding improves the infant’s linear growth outcome.  相似文献   
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The national vaccination campaign against SARS-CoV-2 started in January 2021 in Belgium. In the present study, we aimed to use national hospitalisation surveillance data to investigate the recent evolution of vaccine impact on the risk of COVID-19 hospitalisation. We analysed aggregated data from 27,608 COVID-19 patients hospitalised between October 2021 and February 2022, stratified by age category and vaccination status. For each period, vaccination status, and age group, we estimated risk ratios (RR) corresponding to the ratio between the probability of being hospitalised following SARS-CoV-2 infection if belonging to the vaccinated population and the same probability if belonging to the unvaccinated population. In October 2021, a relatively high RR was estimated for vaccinated people > 75 years old, possibly reflecting waning immunity within this group, which was vaccinated early in 2021 and invited to receive the booster vaccination at that time. In January 2022, a RR increase was observed in all age categories coinciding with the dominance of the Omicron variant. Despite the absence of control for factors like comorbidities, previous infections, or time since the last administered vaccine, we showed that such real-time aggregated data make it possible to approximate trends in vaccine impact over time.  相似文献   
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