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11.
提高湿地农业生态系统的总体功能与效益 总被引:1,自引:0,他引:1
我国农业可概分为湿地农业与旱地农业两大部分。湿地农业区主要分布于占国土面积32%的湿润区,耕地集中,系农副产品重要生产基地。仅以长江中下游地区为例,耕地占全国21%,稻、麦、棉、油菜的总产分别占全国的47%、20%、33.5%和50%,出栏猪头数、禽蛋和淡水鱼产量分别占全国的38.8%、35.8%和58.8%。随着商品经济发展,对湿地农业生产将有更高要求。由此,研究并提高湿地农业生态系统的总体结构、功能与效益就显得很迫切。本文拟以江苏为实例就如何开发与提高湿地农业生态系统的总体功能与效益作如下探讨。 相似文献
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以H2O2为中心的活性氧(reactive oxygen species,ROS)的产生是动植物发育与响应外界生物与非生物胁迫的普遍特征,其在生理和分子2个水平上调控植物的发育和对外界胁迫的响应,并与一系列信号转导过程相关联。作为关键的ROS产生酶,质膜NADPH氧化酶(plasma membrane NADPH oxidase,PM-NOX)在植物应对各种生物和非生物胁迫中具有重要作用,被广泛认为是胁迫条件下植物细胞ROS产生并积累的主要来源。该文简要综述了近年来人们在植物细胞ROS产生、清除、生理功能以及PM-NOX酶的结构特征与功能等方面的研究进展,并认为H2O2-NOX系统是一种植物体内普遍存在的重要发育调控与胁迫响应机制。 相似文献
13.
The hepatitis C virus is a major cause of chronic liver disease worldwide. Lack of culture system supporting virus production
has been one of the major impediments in HCV research and vaccine development. Here, we use a HCV (1b) full-length cDNA clone
that replicates and produces integrated and infectious virus particles in cultured Vero cells. Evidence shows that the replication
of virus particles is robust, producing over 108 copies of positive RNA per milliliter of the culture cells within 48 h. Sucrose density gradient centrifugation of the cell
lysate reveals that the HCV virions have a density of about 1.17 g/ml and a spherical morphology with an average diameter
of about 55 nm. Secreted virus is infectious for Huh7 cells and can be neutralized by CD81- and E2-specific antibodies. This
system establishes a powerful framework for studying the virus life cycle and developing vaccine research. 相似文献
14.
Ipomoea stolonifera (I. stolonifera) has been used for the treatment of inflammatory diseases including rheumatism and rheumatoid arthritis in Chinese traditional medicine. However, the anti-inflammatory activity of I. stolonifera has not been elucidated. For this reason, the anti-inflammatory activity of n-butanol extract of I. stolonifera (BE-IS) was evaluated in vivo by using acute models (croton oil-induced mouse ear edema, carrageenan-induced rat paw edema, and carrageenan-induced rat pleurisy) and chronic models (cotton pellet-induced rat granuloma, and complete Freund’s adjuvant (CFA)-induced rat arthritis). Results indicated that oral administration of BE-IS significantly attenuated croton oil-induced ear edema, decreased carrageenan-induced paw edema, reduced carrageenan-induced exudates and cellular migration, inhibited cotton pellet-induced granuloma formation and improved CFA-induced arthritis. Preliminary mechanism studies demonstrated that BE-IS decreased the levels of myeloperoxidase (MPO) and malondialdehyde (MDA), increased the activity of anti-oxidant enzyme superoxide dismutase (SOD) in vivo, and reduced the production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 in lipopolysaccharide-activated RAW264.7 macrophages in vitro. Results obtained in vivo and in vitro demonstrate that BE-IS has considerable anti-inflammatory potential, which provided experimental evidences for the traditional application of Ipomoea stolonifera in inflammatory diseases. 相似文献
15.
Naifang Hu Yu-Han Zhang Yuan Yang Hui Wu Yuehui Liu Congyi Hao Yue Zheng Deye Sun Wenru Li Jiedong Li Zhiwei Hu Ting-Shan Chan Cheng-Wei Kao Qingyu Kong Xiaogang Wang Shu-Chih Haw Jun Ma Guanglei Cui 《Liver Transplantation》2024,14(13):2303797
Li-rich layered oxides (LRLO) exhibit significant potential for use in all-solid-state lithium batteries (ASSLBs) owing to their high capacities and wide range of operating voltages. However, the practical application of LRLO in ASSLBs is hindered by the severe failure of carrier transport at the solid–solid interface, which subsequently limits the electrochemical activity of these batteries. Here, the spatially asynchronous activation mechanism of the LRLO in ASSLBs is presented. A spectroscopic study extending from the surface into the bulk interior of LRLO indicates that the activation kinetics of anionic oxygen prefers hysteretic delivery over uniform delivery and fast transition metals (TMs) activation. This spatial hetero activation is dominated by the failure of carrier transport at the interface, which is induced by microstructural defects in the composite cathode. This study is expected to facilitate the microstructural design of high-performance LRLO-based ASSLBs. 相似文献
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17.
Extremely low frequency (ELF) pulsed-gradient magnetic fields inhibit malignant tumour growth at different biological levels 总被引:6,自引:0,他引:6
Extremely low frequency (ELF) pulsed-gradient magnetic field (with the maximum intensity of 0.6-2.0 T, gradient of 10-100 T.M(-1), pulse width of 20-200 ms and frequency of 0.16-1.34 Hz treatment of mice can inhibit murine malignant tumour growth, as seen from analyses at different hierarchical levels, from organism, organ, to tissue, and down to cell and macromolecules. Such magnetic fields induce apoptosis of cancer cells, and arrest neoangiogenesis, preventing a supply developing to the tumour. The growth of sarcomas might be amenable to such new method of treatment. 相似文献
18.
Congyi Yang Ruiqian Zhang Hui Lin Hongmei Wang 《Journal of cellular biochemistry》2019,120(10):16362-16369
Osteochondroma is a benign autosomal dominant hereditary disease characterized by abnormal proliferation of cartilage in the long bone. It is divided into solitary osteochondroma and hereditary multiple exostoses (HMEs). The exostosin-1 (EXT-1) and exostosin-2 (EXT-2) gene mutations are well-defined molecular mechanisms in the pathogenesis of HME. EXT-1 and EXT-2 encode glycosyltransferases that are necessary for the synthesis of heparin sulfate. Accumulating evidence suggests that mutations in the EXT family induce changes in isolated hypogonadotropic hypogonadism-parathyroid hormone-related protein, bone morphogenetic protein, and fibroblast growth factor signaling pathways. Studies have also found that a large number of microRNAs (miRNAs) are abnormally expressed in osteochondroma tissues, and some of them also participate in several major signaling pathways. The regulation of miRNA expression could be another breakthrough in the treatment of osteochondroma. Although the pathogenesis of osteochondroma is very complicated, significant progress has been made in recent years. It is hoped that the pathogenesis of osteochondroma will be clearly understood and the most effective methods for the prevention and treatment of osteochondroma will be determined. This review provides an update on the recent progress in the interpretation of the underlying molecular mechanisms of osteochondroma. 相似文献
19.
Chao Shen Meijia Gu Dan Liang Lixia Miao Liu Hu Congyi Zheng Jiakuan Chen 《Cancer cell international》2009,9(1):2-10
Background
Breast cancer is a major malignancy affecting females worldwide. It is the most common cause of death from cancer in women. Cell lines are widely used in laboratory research and particularly as in vitro models in cancer research. But we found that the routinely used breast cancer cell lines were mostly derived from Caucasians or African-Americans. There were few standard models to study the pathogenic mechanism at molecular level and cell signaling pathway of breast cancer for Asian patients. It is quite necessary to establish new breast cancer cell lines from xanthoderm to study the pathogenic mechanism and therapeutic methods. 相似文献20.
苏南丘陵地区土地持续利用模式的建立 总被引:2,自引:0,他引:2
对苏南丘陵地区农田生物结构及功能的研究表明,在荒丘荒坡上建立林地、茶园、果园人工草地及新辟鱼塘以形成农牧渔复合农业生态系统.提出土地持续利用的单元模式;丘岗坡地─—林茶果草立体利用,冲田地─—粮、饲、经、肥、作物合理布局,养殖业—猪、禽、奶牛、鱼全面发展.资源利用─—种养加工业配套成龙.在粮食稳产基础上,农林牧副渔收入增长2.3倍,农用土地收入及人均农业收入均增长2.7倍. 相似文献