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In this paper, Allium tianmuense is described as a new species based on morphological and molecular analyses, and its taxonomic relationships are discussed. It grows in the understorey of deciduous broad-leaved forests at 1000‒1500 m a.s.l. in Tianmu Mountain in Zhejiang (southeast China). Morphological analysis indicates A. tianmuense should be classified into A. sect. Sacculiferum and is distinct from the common species A. thunbergii and A. chinense in the morphology of leaves, umbel, filaments and phenology. Nuclear ribosomal DNA internal transcribed spacer (ITS) phylogenetic analysis further confirmed the inclusion of A. tianmuense within A. sect. Sacculiferum and revealed its distinction from all other species of this section representing a new species.

We examined the dynamics of community structure in forests formed after cutting all以浙江天目山不同海拔(480、580、700和800 m)的毛竹伐除区森林植被为对象,基于群落生态学方法研究2017—2020年各海拔群落的结构变化。结果表明: 2017年所有样地木本植物有515株,隶属于27科43属50种。3 年间增加14科23属30种,个体数量增加116.9%,新增物种主要有毛竹、紫珠、山胡椒、山鸡椒、构树等,主要分布在海拔580和700 m处。2017和2020年海拔580、700和800 m的群落中重要值最大的树种不变,分别为杉木、臭椿和枫香树,而海拔480 m群落重要值最大的树种由杉木变为油茶。各海拔群落径阶分布变化明显。海拔480 m群落径阶分布由倒“J”型发展为单峰左偏态,海拔700 m群落径阶结构由倒“J”型发展为指数型,海拔800 m群落径级分布呈正态分布,峰值由24 cm移到30 cm。3年间各植物群落的Simpson优势度指数和Shannon多样性指数提高,均随海拔升高而显著下降。群落

To investigate the ultrastructural changes of duodenal mucosas and their significance in patients with liver cirrhosis (PLC).Endoscopic biopsy duodenal mucosa specimens of 60 PLC and 18 healthy volunteers as controls were obtained. Ultrastructural changes of them were studied with transmission electron microscopy. These PLC were divided into groups A, B and C according to the Child-Pugh classification. The ultrastructural changes in the duodenal mucosas of each group were rated and compared with those of the other groups. PLC with and without ultrastructural changes of duodenal mucosas were divided into a positive group and a negative group. Levels of plasma Alb, TBil, PT, plasma endotoxin, and blood ammonia of the PLC were detected and compared.There were 20 PLC each in groups A, B, and C. Ultrastructural changes of duodenal mucosas were found in 5 PLC of group A, 9 in group B and 17 in group C. Among the 60 PLC, 52% had some changes in their duodenal mucosas. The changes included decrease and rupture of the microvilli; also karyopyknosis, karyorrhexis, widening of the gaps of the tight junction and tumefactions of mitochodrion of duodenal mucosa epithelial cells. No ultrastructural changes of duodenal mucosas were found in the control group. The rate of changes in the three Child-Pugh class groups and in the control group were 25%, 45%, 85%, 0% respectively (P0.01). The level of Alb of the positive group was significantly lower than that of the negative group (P0.01). Levels of plasma TBil, PT, endotoxin and blood ammonia of the positive group were significantly higher or longer than those of the negative group (P0.01). Levels of plasma Alb of the positive and negative groups were significantly lower than those of the control group (P0.01). Levels of TBil, PT, plasma endotoxin and blood ammonia of the positive and negative groups were significantly higher or longer than those of the control group (P0.01).There were ultrastructural changes of duodenal mucosas in PLC, especially in end-stage PLC. Ultrastructural changes of intestinal mucosas in the PLC may have important pathophysiological and clinical significance.