ABSTRACT
BACKGROUND: With advancements in medicine and economy, it would be expected that there will be changes in the clinical characteristics of upper respiratory papillomatosis. The aim of this study was to examine the current clinical characteristics of upper respiratory papillomatosis, as there are no recent data in the literature. METHODS: The medical records of 1894 patients with upper respiratory papillomatosis were retrospectively reviewed. Data extracted included clinical features, laryngoscopy images, and surgical procedure data. RESULTS: The upper frequency of upper respiratory papillomatosis in the oropharynx was 69.1 %, and in the larynx was held 28.9 %. The overall postoperative relapse rate was 2.4 %. The relapse rate of laryngeal papillomatosis was 6.5 %. Approximately 2.6 % of cases were in children. All postoperative recurrences in children were laryngeal, and the recurrence rate was 30.4 %. CONCLUSION: The oropharynx has the highest frequency of upper respiratory papillomatosis. The larynx, however, has the highest rate of postoperative recurrence. Compared to adults, children are more likely to experience a postoperative recurrence.
ABSTRACT
Soil freeze-thaw could affect nitrogen (N) availability. The N transformation is closely related with soil microbes. The effect of soil freeze-thaw on the soil bacterial communities in the temperate zone is still not clear. We hypothesized that freeze-thaw events could affect the diversity and composition of bacterial communities, thereby changing the contents of soil dissolved nitrogen pools as well as the N transformation process. In this study, microcosms with different freeze-thaw cycles (six and fifteen cycles) were designed, with the constant temperature at 2 â as the control. The results showed that the contents of dissolved total nitrogen, dissolved inorganic nitrogen, microbial biomass nitrogen and net nitrogen mineralization rate were decreased significantly in response to increasing cycles of freeze-thaw. The number of freeze-thaw cycles did not affect bacterial α diversity. In contrast, the duration of incubation was positively correlated with bacterial α diversity including Chao1 and Shannon indices. Freeze-thaw treatment significantly affected the function and composition of bacterial communities, but the number of freeze-thaw cycles had little effect on the bacterial community structure. The partial redundant analysis showed that under freeze-thaw treatments, both the composition and function of bacterial community were significantly related to soil dissolved N pools and N transformation processes.
