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排序方式: 共有183条查询结果,搜索用时 109 毫秒
1.
利用综合防治方法对加格达奇兴安落叶松种子园落叶松球果花蝇进行防治,结果表明:防治效果达到90%时,种子园出种率提高了10%,大幅度减少良种种子损失,增加良种供给率。 相似文献
3.
湿地是自然界富有较高生物多样性和生产力的生态系统,不但具有丰富的资源,还有巨大的环境调节功能和生态效益。各类湿地在提供水资源、调节气候、涵养水源、均化供水、促淤造陆、降解污染物、保护生物多样性和为人类提供生产、生活资源等方面都有重要的意义,被誉为“地球之肾”、“生命的摇篮”等,每年的2月2日为世界湿地日。 相似文献
4.
Qian Qu Xiaowei Wu Qing Zhou Shaoping Lu Xuan Yao Liang Guo Liangqian Yu 《中国油料作物学报(英文)》2023,(4):243-251
Reactive oxygen species(ROS) play a key role in a variety of biological processes, such as the perception of abiotic stress, the integration of different environmental signals, and the activation of stress response networks. Salt stress could induce an increased ROS accumulation in plants, disrupting intracellular redox homeostasis, leading to posttranslational modifications(PTMs) of specific proteins, and eventually causing adaptive changes in metabolism.Here, we performed an iodo TMT-based pro... 相似文献
5.
减温减压器在电厂、石化、造纸、医药、供暖等诸多领域有着广泛的运用.对此,文章以减温减压器及可调弹簧喷嘴技术为主要研究对象,针进减温减压器的设备组成、减温减压器可掉弹簧喷嘴技术、减温减压器设备维护等内容进行分析,研究减温减压器的应用价值,以设备结构、设备功能、设备维护为研究目的,探究减温减压器的运行注意事项和维护方法,以... 相似文献
6.
鸡痛风病是一种群发性、危害大的商品鸡常见病.引起鸡痛风病的原因很多,不同的病因所导致的症状也有所不同.为了防止病害大面积发生,要做好预防工作,并及时治疗,提高养殖业的生产效率和经济效益. 相似文献
7.
When crude enzymes prepared from some vegetables and fruits were incubated with bisphenol A (2,2-bis(4-hydroxyphenyl)propane, BPA) at 37 degrees C, BPA was oxidized by crude enzymes from potato, eggplant, and lettuce. The crude enzyme prepared from potato (Solanum tuberosum) had the strongest oxidative activity for BPA. Its optimal temperature and pH were 40-45 degrees C and 8.0, respectively. More than 95% of BPA was oxidized after the incubation with potato enzyme for 60 min. BPA gave two oxidation products besides insoluble compounds during the oxidation by potato enzyme. The oxidation products were identified to be 4[1-(4-hydroxyphenyl)-1-methyl-ethyl]-benzene-1,2-diol and 4[1-(4-hydroxyphenyl)-1-methyl-ethyl]-benzene-1,3-diol. Enzymatically oxidized BPA lost the estrogen-like activity to enhance the growth of human breast cancer (MCF-7) cells. 相似文献
8.
Makala LH Reyes JC Nishikawa Y Tsushima Y Xuan X Huang X Battsetseg B Matsuo T Nagasawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(4):491-499
The phenotype and function of peritoneal cavity macrophage-derived dendritic cells (PEC-DC) was previously reported. In this study we have gone further in using our established culture system to generated discrete Peyer's patch dendritic cells (DPP-DC) from murine discrete Peyer's patch macrophages (DPP-M?), following stimulation with granulocyte macrophage colony stimulating factor (GM-CSF) plus interleukin 4 (IL-4) for 7 days. DPP-M? from murine small intestines were obtained by mechanical disruption of discrete Peyer's patches (DPP), followed by metrizamide density gradient centrifugation to remove Peyer's patch resident DC and debri, after which an overnight adherent step in tissue culture medium was carried out for macrophage enrichment. Characterization of the generated DPP-DC was carried out using well-established criteria of morphology, expression of membrane antigens and capacity for antigen presentation. Dendritic cells expressed DEC-205, F4/80 and CD34 at high levels, but exhibited very low CD11c levels. They were shown to present soluble protein antigen to CD3(+) spleen T cells. A comparison of the surface antigen expression in the progenitor DPP-M? population and the generated DPP-DC showed a significant decrease in MHC class II levels and a marked down regulation of the co-stimulatory molecule CD86 (B7-2). High expression of the haemopoietic progenitor marker CD34 indicates that the generated DC, possess a haemopoietic rather than myeloid origin. Taken together, these results may provide a better understanding of the complex network regulating mucosal immune responses. 相似文献
9.
Immunogenic properties of a bovine herpesvirus-1 (BHV-1) recombinant expressing major pseudorabies virus (PrV) glycoproteins in combination 总被引:1,自引:0,他引:1
Ikeda Y Shibata I Xuan X Matsumoto Y Otsuka H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(8):849-859
A recombinant bovine herpesvirus type 1 (BHV-1), designated BHV-1/TF17-1, which expresses pseudorabies virus (PrV) glycoproteins gB, gC, gD, gE and gI in combination was constructed. To test the protective immunity, 10 mice were inoculated with BHV-1/TF17-1 and three weeks later 10 mice were intraperitoneally (i.p.) challenged with 20 LD50 virulent PrV (YS-81). BHV-1/TF17-1 protected all the mice from the PrV lethal challenge while all the control mice died in around 3 days. Mice vaccinated with BHV-1/TF17-1 acquired high PrV-neutralizing antibody titers and demonstrated strong delayed type hypersensitivity responses and moderate in vitro lymphocyte proliferative responses to PrV antigen. Since the major PrV glycoproteins were integrated into virions (probably into viral envelope), BHV-1/17-1 was neutralized with anti-PrV antiserum. However, the susceptibility of BHV-1/TF17-1 to anti-PrV antiserum is 2- to 4-fold lower than that of PrV vaccine lines. Our results demonstrated the possibility of BHV-1/17-1 as a vaccine to protect piglets from Audjesky's disease where maternal antibodies against PrV interfere attenuated live PrV vaccines. 相似文献
10.
陕西省耕地面积变化趋势及其驱动因子研究 总被引:15,自引:2,他引:15
以实地调查和统计资料,分析了陕西省1949-2003年55 a间耕地面积变化的总体趋势.运用主成分分析方法定量分析了耕地面积变化的驱动因子,结果表明:社会-经济-科技综合作用、退耕还林等2大类因素是影响耕地面积变化的2个主成分.通过建立多元回归模型,对陕西省2010年和2015年的耕地面积进行了预测.研究结果将为合理利用和保护耕地,为干旱地区农业可持续发展提供科学依据. 相似文献