LUO ShuzhengZHANG JianhuaZHANG HufangZHENG Qingrong...
77-87页
查看更多>>摘要：In order to explore the response of soil respiration in grassland to global warming,we carried out a warming experiment with open top chambers(OTCs)in the subalpine meadow,Mount Wutai in north China.Our results showed in the subalpine meadow across 2 500-2 700 m above the sea level(ASL),with OTCs,soil respiration increased by 2.00 pmol.m-2.s-1as soil temperature increased by 1.25℃on average.Warming decreased soil moisture over the experiment periods except in October 2019 when snow melted in OTCs.Warming effect on soil respiration peaked at 178.31％in October 2019.In control and warming treatment,based on exponential regression equations,soil temperature alone accounted for 85.3％and 61.2％of soil respiration variation,respectively.In control treatment soil mois-ture alone explained 23.2％of soil respiration variation based on the power regression equation while in warming treatment they were not significantly correlated with each other.The response of soil respiration to warming relied on altitudes as well as the time of the year,but was not inhibited by soil moisture,labile carbon pool,and available nitrogen.We concluded soil temperature was the main factor influenc-ing soil respiration,and global warming would stimulate soil respiration in the subalpine meadows of Mount Wutai in the future.Our analysis provided new data on characteristics and mechanisms of the response of soil respiration to warming,and helped to further under-stand the relationship between carbon cycle and climate change.
查看更多>>摘要：This study aims to compare the differences in sampling satisfaction rates between 5 mL syringe and 22G percutaneous transhe-patic cholangiography(PTC)needles in fine-needle aspiration(FNA)to provide economical and reasonable needle selection.From Janu-ary 2021 to March 2022,187 patients with thyroid nodules(a total of 200 nodules)who underwent ultrasound-guided FNA were punctured using 22G PTC and 5 mL syringe needles once for each nodule,and the sample was sent for pathological examination.The sample satisfac-tion rate of the two methods was statistically analyzed,and factors affecting the sample satisfaction rate were determined.Results demon-strated that the overall sample satisfaction rates of 5 mL syringes and 22G PTC needles were 83％and 85％(P＞0.05),respectively.The sat-isfaction rates of the two specimens were 92.6％and 91.1％(P＞0.05)among 136 nodules with poor blood supply.For 64 nodules with rich blood supply,the satisfaction rate of both specimens was significantly lower than that of the nodule with poor blood supply(P＜0.05),and that of the 5 mL syringe needle was significantly lower than that of the latter(62.5％vs.71.8％,P＜0.05).The results suggest that satisfac-tory sampling results can be obtained using either a 5 mL syringe or 22G PTC needles.The 22G PTC needle is more likely to yield FNA re-sults if the nodule is rich in blood supply.
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