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931.
我国是世界上植物多样性最丰富的国家之一, 1999年发布的《国家重点保护野生植物名录》(下称《名录》(第一批))明确了国家重点保护野生植物的范围, 为依法强化保护、规范无序开发利用、提高公众保护意识奠定了基础。20多年来, 我国野生植物多样性保护形势发生了很大变化, 需要对《名录》进行调整。2018年, 国家林业和草原局、农业农村部启动《名录》调整工作, 物种的遴选遵循了5条基本原则和4条补充性原则, 这些原则主要涉及中国珍稀濒危物种, 具有重要经济、文化、科研、生态等价值物种的入选以及部分物种的排除。经国务院批准, 2021年9月7日, 国家林业和草原局、农业农村部发布了调整后的《名录》, 包括真菌类、藻类、苔藓、石松类和蕨类植物、裸子植物和被子植物, 共计约1,101种(455种和40类)野生植物列入其中。本文简要介绍了《名录》调整的必要性、原则和程序及调整后的情况。  相似文献   
932.
为明确晋西黄土区植物的水分利用规律及对半干旱区的适应策略, 提高黄土地区植被建设效益, 该研究对该地区典型乔灌木短期水分利用效率随环境因子的变化进行了探究。以典型乔木油松(Pinus tabuliformis)、刺槐(Robinia pseudoacacia)及其林下灌木黄刺玫(Rosa xanthina)、杠柳(Periploca sepium)为研究对象, 测定叶片可溶性糖稳定碳同位素比值(δ13Cleaf)与枝条渗出液稳定碳同位素比值(δ13Cbranch), 使用δ13Cleaf推导计算7-10月叶片尺度下植物短期水分利用效率(WUEleaf)变化趋势, 使用δ13Cbranch明确植物光合作用后分馏情况, 确定半干旱区植物在生长季的水分变化规律对环境因子变化的响应。结果表明: (1) 7-10月4种植物δ13Cleaf总体呈现降低趋势, δ13Cbranch呈现先升高后降低趋势。δ13Cleaf在种间和生活型中均存在差异。具体表现为: 灌木>乔木, 常绿乔木(油松) >落叶乔木(刺槐)。研究过程中未发现明显的碳同位素在光合作用后发生分馏的情况。(2) 4种植物WUEleaf在7-8月保持稳定, 9-10月逐渐升高。21.5 ℃、0.9 kPa、52.4%分别为WUEleaf随温度(Ta)、饱和水汽压差(VPD)、相对湿度(RH)变化的突变点, 突变点之后4种植物WUEleaf均表现出稳定的变化趋势, 不再随TaVPDRH升高而降低。(3) WUEleafTaRHVPD之间存在显著负相关关系, Ta通过非气孔因素, 即酶的作用改变光合速率, 引起WUEleaf变化。RHVPD等水分因子则通过改变气孔开度, 影响蒸腾, 进而改变WUEleaf。随着土壤含水量(SWC)的升高, WUEleaf呈现先升高后降低的趋势。油松林和刺槐林在SWC分别达到15%-18%、13%-14%时, WUEleaf达到最高值。经过混合线性模型(LMM)分析得到, 油松和刺槐WUEleaf主导环境因子分别为RHVPD, 黄刺玫和杠柳WUEleaf主导环境因子均为Ta。该研究得到了黄土地区典型乔灌木生长季水分利用效率变化的规律和主要环境影响因子, 明确了黄土地区植物对气候因子变化的适应机制。  相似文献   
933.
934.
Journal of Physiology and Biochemistry - Cardiovascular disease (CVD) is one of the vital causes of morbidity and mortality, and the number of deaths from CVD has increased worldwide. Circular RNAs...  相似文献   
935.
936.
With the development of genomics, the update of modern imaging technology and the advent of artificial intelligence and big data, the surgical treatment of gastric cancer has gradually stepped into precision medicine. Precision surgery treatment of gastric cancer is based on accurate molecular typing and staging using modern molecular diagnostic technology and imaging, and the formulation of precise and individualized surgical treatment plans, with the concept of minimally invasive and accelerated rehabilitation surgery running through it. For intermediate-stage gastric cancer, we have adopted a comprehensive treatment approach including traditional radiotherapy and chemotherapy, targeted therapy and immunotherapy. Utilize artificial intelligence and big data technology to improve the standardization and interconnectivity of specialty data and realize the transformation of evidence-based medicine. Promoting the standardization, standardization and individualization of gastric cancer surgical treatment, providing patients with precise diagnosis and treatment, and further improving patients'' prognosis are the opportunities and challenges in the development of gastric cancer surgery.  相似文献   
937.
Liver cancer was reported to be the sixth most frequently diagnosed cancer, and hepatocellular carcinoma (HCC) accounts for 75%-85% of primary liver cancer. Nevertheless, the concrete molecular mechanisms of HCC progression remain obscure, which is essential to elucidate. The expression profile of RAD54B in HCC was measured using qPCR and western blotting. Moreover, the levels of RAD54B in paraffin-embedded samples were evaluated using immunohistochemistry (IHC). The effect of RAD54B on HCC progression was testified by in vitro experiments, and in vivo orthotopic xenograft tumor experiments. The mechanisms of RAD54B promoting HCC progression were investigated through molecular and function experiments. Herein, RAD54B are dramatically upregulated in HCC tissues and cell lines both on mRNA and protein levels, and RAD54B can servers as an independent prognostic parameter of 5-year overall survival and 5-year disease-free survival for patients with HCC. Moreover, up-regulation of RAD54B dramatically increases the capacity for in vitro cell viability and motility, and in vivo intrahepatic metastasis of HCC cells. Mechanistically, RAD54B promotes the HCC progression through modulating the wnt/β-catenin signaling. Notably, blocking the wnt/β-catenin signaling axis can counteract the activating effects of RAD54B on motility of HCC cells. Besides, further analysis illustrates that DNA amplification is one of the mechanisms leading to mRNA overexpression of RAD54B in HCC. Our findings indicate that RAD54B might be a promising potential prognostic marker and a candidate therapeutic target to therapy HCC.  相似文献   
938.
Olfactory neuroepithelium (ONe) is unique because it contains progenitor cells capable of mitotic division that replace damaged or lost neurons throughout life. We isolated populations of ONe progenitors from adult cadavers and patients undergoing nasal sinus surgery that were heterogeneous and consisted of neuronal and glial progenitors. Progenitor lines have been obtained from these cultures that continue to divide and form nestin positive neurospheres. In the present study, we used clonal and population analyses to probe the self-renewal and multipotency of the neurosphere forming cells (NSFCs). NSFCs plated at the single cell level produced additional neurospheres; dissociation of these spheres resulted in mitotically active cells that continued to divide and produce spheres as long as they were subcultured. The mitotic activity of clonal NSFCs was assessed using bromodeoxyuridine (BrdU) incorporation. Lineage restriction of the clonal cultures was determined using a variety of antibodies that were characteristic of different levels of neuronal commitment: β-tubulin isotype III, neural cell adhesion molecule (NCAM) and microtubule associated protein (MAP2), or glial restriction: astrocytes, glial fibrillary acidic protein (GFAP); and oligodendrocytes, galactocerebroside (GalC). Furthermore, nestin expression, a marker indicative of progenitor nature, decreased in defined medium compared to serum-containing medium. Therefore, adult human ONe-derived neural progenitors retain their capacity for self-renewal, can be clonally expanded, and offer multipotent lineage restriction. Therefore, they are a unique source of progenitors for future cell replacement strategies in the treatment of neurotrauma and neurodegenerative diseases.  相似文献   
939.
940.
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