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1.
报道了我国玄参科的一个新记录属──囊萼花属CyrtandromoeaZoll,该属为印度-马来西亚分布,它经过泰国北部,缅甸与我国发生连系,到达我国云南贡山、屏边、金平。全世界有11—12种,我国(云南)首次记录两种,其中一种为新种。  相似文献   
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Here, we publish Lepisorus sect. Paragramma (Blume) C.F. Zhao, R. Wei & X.C. Zhang as a combinatio nova to replace the section name in Zhao et al. (2020), which was published as a status nova and turned out to be an invalid name, because we cited an incorrect basionym. A revised infrageneric classification of Lepisorus also is proposed.  相似文献   
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After significant injury, the liver must maintain homeostasis during the regenerative process. We hypothesized the existence of mechanisms to limit hepatocyte proliferation after injury to maintain metabolic and synthetic function. A screen for candidates revealed suppressor of cytokine signaling 2 (SOCS2), an inhibitor of growth hormone (GH) signaling, was strongly induced after partial hepatectomy. Using genetic deletion and administration of various factors we investigated the role of SOCS2 during liver regeneration. SOCS2 preserves liver function by restraining the first round of hepatocyte proliferation after partial hepatectomy by preventing increases in growth hormone receptor (GHR) via ubiquitination, suppressing GH pathway activity. At later times, SOCS2 enhances hepatocyte proliferation by modulating a decrease in serum insulin-like growth factor 1 (IGF-1) that allows GH release from the pituitary. SOCS2, therefore, plays a dual role in modulating the rate of hepatocyte proliferation. In particular, this is the first demonstration of an endogenous mechanism to limit hepatocyte proliferation after injury.  相似文献   
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中国梧桐属(Firmiana)在世界梧桐属中占比较大,且除梧桐外其余种均为中国特有且分布范围狭窄的植物种,灭绝风险大,研究气候变化对中国梧桐属树种的影响对于维护生物多样性具有重要的意义。结合多时期第六次国际气候耦合模式比较计划(CMIP6)气候变量数据和中国八种梧桐属树种的分布数据,基于R语言kuenm程序包优化的最大熵(Maxent)模型模拟分析中国八种梧桐属树种在多尺度下的潜在适生区,得出梧桐属最适宜的模拟尺度、潜在适生区的面积变化和迁移方向、梧桐属多样性保护关键区域及保护空缺。结果表明:(1)梧桐属最适宜的模拟尺度为亚洲;(2) Maxent模型的接收者操作特征曲线下面积(AUC)值均大于0.9,表明模型对梧桐属潜在适生区预测结果具有较高准确度;(3)气候变化影响下除云南梧桐(Firmiana major)外其它树种的潜在适生区都将在未来有所扩大;(4)中国八种梧桐属树种潜在适生区迁移方向主要为东西向,南北向大跨度迁移较少,纬度变化不大;(5)丹霞梧桐(Firmiana danxiaensis)的稳定潜在适生区最小;(6)中国梧桐属多样性保护关键区域主要分布于广西壮族自治区及云南、广东、海南等省区;(7)中国梧桐属多样性保护空缺区域主要分布于广西壮族自治区中部及海南省北部;(8)梧桐属多样性保护关键区域正在为人造地表所侵蚀。研究分析气候变化对中国八种梧桐属树种的影响及其潜在适生区变化、中国梧桐属多样性保护状态,可为中国梧桐属建立多样性保护廊道提供相关建议,为制定多样性保护规划及相应措施提供参考。  相似文献   
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This study aimed to identify significant biomarkers related to the prognosis of liver cancer using long noncoding RNA (lncRNA)-associated competing endogenous RNAs (ceRNAs) analysis. Differentially expressed mRNA and lncRNAs between liver cancer and paracancerous tissues were screened, and the functions of these mRNAs were predicted by gene ontology and pathway enrichment analyses. A ceRNA network consisting of differentially expressed mRNAs and lncRNAs was constructed. LncRNA FENDRR and lncRNA HAND2-AS1 were hub nodes in the ceRNA network. A risk score assessment model consisting of eight genes (PDE2A, ESR1, FBLN5, ALDH8A1, AKR1D1, EHHADH, ADRA1A, and GNE) associated with prognosis were developed. Multivariate Cox regression suggested that both pathologic_T and risk group could be regarded as independent prognostic factors. Furthermore, a nomogram model consisting of pathologic_T and risk group showed a good prediction ability for predicting the survival rate of liver cancer patients. The nomogram model consisting of pathologic_T and a risk score assessment model could be regarded as an independent factor for predicting prognosis of liver cancer.  相似文献   
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Drought significantly affects the architectural development of maize inflorescence, which leads to massive losses in grain yield. However, the genetic mechanism for traits involved in inflorescence architecture in different watering environments, remains poorly understood in maize. In this study, 19 QTLs for tassel primary branch number (TBN) and ear number per plant (EN) were detected in 2 F2:3 populations under both well-watered and water-stressed environments by single environment mapping with composite interval mapping (CIM); 11/19 QTLs were detected under water-stressed environments. Moreover, 21 QTLs were identified in the 2 F2:3 populations by joint analysis of all environments with a mixed linear model based on composite interval mapping (MCIM), 11 QTLs were involved in QTL × environment interactions, seven epistatic interactions were identified with additive by additive/dominance effects. Remarkably, 12 stable QTLs (sQTLs) were simultaneously detected by single environment mapping with CIM and joint analysis through MCIM, which were concentrated in ten bins across the chromosomes: 1.05_1.07, 1.08_1.10, 2.01_2.04, 3.01, 4.06, 4.09, 5.06_5.07, 6.05, 7.00, and 7.04 regions. Twenty meta-QTLs (mQTLs) were detected across 19 populations under 51 watering environments using a meta-analysis, and 34 candidate genes were predicted in corresponding mQTLs regions to be involved in the regulation of inflorescence development and drought resistance. Therefore, these results provide valuable information for finding quantitative trait genes and to reveal the genetic mechanisms responsible for TBN and EN under different watering environments. Furthermore, alleles for TBN and EN provide useful targets for marker-assisted selection to generate high-yielding maize varieties.  相似文献   
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Fluid-structural coupling occurs when microcantilever sensors vibrate in a fluid. Due to the complexity of the mechanical characteristics of microcantilevers and lack of high-precision microscopic mechanical testing instruments, effective methods for studying the fluid-structural coupling of microcantilevers are lacking, especially for non-rectangular microcantilevers. Here, we report fluid-structure interactions (FSI) of the cable-membrane structure via a macroscopic study. The simplified aeroelastic model was introduced into the microscopic field to establish a fluid-structure coupling vibration model for microcantilever sensors. We used the finite element method to solve the coupled FSI system. Based on the simplified aeroelastic model, simulation analysis of the effects of the air environment on the vibration of the commonly used rectangular microcantilever was also performed. The obtained results are consistent with the literature. The proposed model can also be applied to the auxiliary design of rectangular and non-rectangular sensors used in fluid environments.  相似文献   
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