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51.
石油污染土壤降解与土壤的环境关系 总被引:4,自引:0,他引:4
阐述了石油污染土壤的降解与土壤环境的关系;提出如何消除石油污染土壤降解的环境限制因子,为微生物降解石油提供最理想环境,是有效治理石油污染的关键. 相似文献
52.
通过水稻旱作全程覆膜与半程覆膜、旱作不覆膜及水栽对比试验,研究其耗水规律,计算其节水量与增产量,并进行经济效益分析,提出了适合本地区的栽培模式。 相似文献
53.
54.
吴震 《湖南农业大学学报(自然科学版)》2011,(1):11-17
朱熹“敬论”既继承了程颐主敬说,而又有全面的理论整合及发挥,是其整个理学思想的重要一环。朱熹由其“心是做功夫处”的心论立场出发,极力反对在心的操舍存亡的功夫论问题上预设“另有心之本体”的前提,与此相应,其主敬功夫也就不是道德本心的直接发动,而是对心的知觉意识等各种功能的控制调整,其云“敬只是此心自做主宰处”、“以敬为主而心自存”、“将个敬字收敛个身心”、都是在这个意义上说的。然朱熹主敬自有一套理路,其核心关怀在于如何解决现实人心的障蔽问题,未尝不是儒学功夫论的一种理论形态。 相似文献
55.
The dispersal ecology of most stream fishes is poorly characterised, complicating conservation efforts for these species. We used microsatellite DNA marker data to characterise dispersal patterns and effective population size (Ne) for a population of Roanoke logperch Percina rex, an endangered darter (Percidae). Juveniles and candidate parents were sampled for 2 years at sites throughout the Roanoke River watershed. Dispersal was inferred via genetic assignment tests (ATs), pedigree reconstruction (PR) and estimation of lifetime dispersal distance under a genetic isolation‐by‐distance model. Estimates of Ne varied from 105 to 1218 individuals, depending on the estimation method. Based on PR, polygamy was frequent in parents of both sexes, with individuals spawning with an average of 2.4 mates. The sample contained 61 half‐sibling pairs, but only one parent–offspring pair and no full‐sib pairs, which limited our ability to discriminate natal dispersal of juveniles from breeding dispersal of their parents between spawning events. Nonetheless, all methods indicated extensive dispersal. The AT indicated unrestricted dispersal among sites ≤15 km apart, while siblings inferred by the PR were captured an average of 14 km and up to 55 km apart. Model‐based estimates of median lifetime dispersal distance (6–24 km, depending on assumptions) bracketed AT and PR estimates, indicating that widely dispersed individuals do, on average, contribute to gene flow. Extensive dispersal of P. rex suggests that darters and other small benthic stream fishes may be unexpectedly mobile. Monitoring and management activities for such populations should encompass entire watersheds to fully capture population dynamics. 相似文献
56.
AIM:To determine whether suspension culture medium without insulin can be used to feed breast cancer tumorsphere, or not. METHODS:MCF7 cells were used to build tumorsphere. The morphological changes, CD44+ CD24- expression, aldehyde dehydrogenase 1 (ALDH1) expression and multiple division ability were measured to identify the breast cancer stem cells and to detect the function of 17β-estradiol (E2β) in tumorsphere of MCF7 cells. RESULTS:The tumorshere, each containing 30 to 60 cells, was obtained by the method of insulin-removal suspension culture. These cells were cytokeratin 18 and CD10 proteins positive, and the number of CD44+ CD24- cells and ALDH1 protein expression were significantly higher than the adherent cultured cells (P<0.05). Using 10-10 mol/L E2β to treat the tumorshere for 7 d, the tumor cell number and volume were significantly increased. Using 10-10 mol/L E2β to treat the tumorshere for 24 h, the CD44+ CD24-cells and ALDH1 protein expression were significantly higher than those in non-treatment group (P<0.05). CONCLUSION: Suspension culture medium without insulin can be used to feed breast cancer tumorsphere. These tumorsphere could be used as a model to determine the function of E2β in breast cancer stem cell research. 相似文献
57.
秦岭林区雷击火的发生和预防 总被引:1,自引:0,他引:1
结合实践,分析了秦岭林区雷击火发生、蔓延的条件和趋势,提出了预防和扑救的技术与方法. 相似文献
58.
彭程甸 《湖南农业大学学报(自然科学版)》2000,(1)
江泽民从建设社会主义市场经济和民主政治,维护国家长治久安的客观需要出发,继承与发展邓小平法治思想,提出了"依法治国、建设社会主义法治国家"的治国方略;江泽民法治思想的核心和最高成就是依法治国,建设社会主义法治国家;其法治思想的具体内容包括加强立法、依法行政、司法改革、普法教育、发展法律服务业. 相似文献
59.
AIM:To investigate the protective effect of insulin like growth factor-1 (IGF-1) against radiation-induced injury in c17.2 neural stem cells.METHODS:c17.2 neural stem cells were cultured in vitro and identified by nestin immunohistochemistry and X-gal staining.The IGF-1 adenoviral vector was transfected into c17.2 neural stem cells.The expression of IGF-1 was detected by IGF-1 immunohistochemistry.Necrosis and apoptosis of c17.2 neural stem cells were induced by radiation at doses of 4 Gy,6 Gy and were detected by flow cytometry and TUNEL test.The effect of IGF transfection on the degree of necrosis and apoptosis in these cells was also observed.RESULTS:c17.2 cells were identified by nestin and X-gal staining.Immunohistochemistry verified the expression of IGF-1 in the c17.2 neural stem cells transfected with adenoviral vector.At the same doses of radiation,the rates of apoptosis and necrosis in c17.2 neural stem cells transfected with IGF-1 were lower than those in the cells without IGF-1 adenoviral vector transfection.CONCLUSION:The rate of necrosis and apoptosis of c17.2 neural stem cells induced by radiation is decreased by transfection of IGF-1 adenoviral vector.IGF-1 shows a protective effect on c17.2 cells. 相似文献
60.
AIM: To investigate the potential of murine epidermal stem cell (ESC) differentiation after seeded in a biodegradable carrier and implanted subcutaneously into syngeneic recipient mice. METHODS: ES cells were induced in vitro to differentiate into ESCs. After stained with a fluorescent dye Hoechst 33342, these ESCs were seeded into a polyglycolic acid (PGA) net containing collagen gel, functioning as a cell carrier, and implanted subcutaneously into 129/J mice, which were syngeneic to these stem cells. RESULTS: The ESCs kept alive in the implant when observed under a fluorescent microscopy 3 weeks or longer after implantation, and could differentiate into hair follicle-like structure, glandular structure, and gave rise to additional structures displaying features resembling native dermis. No apparent rejection or severe side effects were observed at least 10 weeks post-implantation. CONCLUSION: It is feasible to use these ESCs as seed cells in the study to fabricate dermal equivalent having the potential to develop dermal appendages. 相似文献