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排序方式: 共有1610条查询结果,搜索用时 31 毫秒
11.
植物内生固氮菌研究进展 总被引:2,自引:0,他引:2
综述了植物内生固氮菌生物多样性、生物学特性 ,生理特性 ,与寄主植物的相互作用及应用前景等方面的研究进展。 相似文献
12.
色氨酸的生理生化作用及其应用 总被引:23,自引:2,他引:21
主要介绍了色氨酸在人体内的生理作用、代谢途径及其在医学和工业领域的应用。 相似文献
13.
S-腺苷甲硫氨酸的研究现状及应用前景 总被引:7,自引:0,他引:7
介绍了S-腺苷甲硫氨酸的制备方法及稳定性研究现状,并对其临床应用及市场前景进行了分析。 相似文献
14.
15.
叉孢苏铁ISSR反应条件的优化及初步应用 总被引:9,自引:0,他引:9
利用ISSR 技术对叉孢苏铁(Cycas segmentifida)遗传多样性进行研究,对影响PCR 反应的DNA 模板浓度、dNTP 浓度、Taq 酶含量、引物浓度、Mg2 浓度和退火温度等进行了条件优化。叉孢苏铁的ISSR 最佳反应扩增体系为20μl 反应体积2μl 10 ×PCR buffer,模板DNA20ng,1UTaq 酶,1.5~2.75mmol/L MgCl2,0.1mmol/L 4 ×dNTP,0.22μmol/L 引物,2%甲酰胺。适宜的退火温度为50~52℃。从103 条引物中筛选出12 条用于所有样品的扩增,共扩增出122 条带,其中多态性条带为86 条,占总条带数的70.49%。POPGENE分析结果表明,种级水平上,叉孢苏铁具有中等稍高的遗传多样性水平,且各居群间有着很高的遗传分化度。 相似文献
16.
目的:探讨介入治疗股骨头缺血坏死的临床应用价值。方法:采用Seldinger技术对28例患者行超选择股骨头供血动脉插管,动脉造影、溶通治疗。结果:28例患者治疗后髋部疼痛及关节功能障碍均有不同程度的减轻及改善,有效率96.4%;治疗后病变区血管分支增多、增粗;影像随访显示股骨头骨质不同程度修复。结论:介入治疗具有创伤小、并发症低、血管再通率高、临床症状改善明显的优势,能有效的改善股骨头的局部血液循环和髋关节的疼痛、活动功能,应大力推广。 相似文献
17.
S. Promsakha Na. Sakonnakhon B. Toomsan G. Cadisch E. M. Baggs P. Vityakon V. Limpinuntana S. Jogloy A. Patanothai 《Plant and Soil》2005,272(1-2):183-199
It is generally thought that grain legume residues make a substantial net N contribution to soil fertility in crop rotation systems. However, most studies focus on effects of residues on crops immediately sown after the legume crop while in fact in many tropical countries with a prolonged dry season there is a large gap before planting the next crop with potential for nutrient losses. Thus the objectives of this study were* to improve the efficiency of groundnut (Arachis hypogaea L.) stover-N (100 kg N ha –1) recycling by evaluating the effect of dry season stover management, i.e. surface application and immediate incorporation after the legume crop or storage of residues until next cropping in the rainy season. N dynamics (litterbags, mineral N, microbial biomass N, N 2O emissions) were monitored and 15N labelled residues were applied to assess the fate of residue N in the plant–soil (0–100 cm) system during two subsequent maize crops. Recycling groundnut stover improved yield of the subsequent maize (Zea mays L.) crop compared to treatment without stover. A higher N recycling efficiency was observed when residues were incorporated (i.e. 55% total 15N recovery after second maize crop) than when surface applied (43% recovery) at the beginning of the dry season. This was despite the faster nitrogen release of incorporated residues, which led to more mineral N movement to lower soil layers. It appears that a proportion of groundnut stover N released during the dry season was effectively captured by the natural weed population (54–70 kg N ha –1) and subsequently recycled particularly in the incorporation treatment. Despite the presence of weeds major leaching losses occurred during the onset of the rainy season while N 2O emissions were relatively small. There was a good correlation between soil microbial biomass N and first crop maize yield. Incorporation of groundnut residues led to small increases in economic yield, i.e., 3120 versus 3528 kg ha –1 over two cropping cycles in the surface versus incorporation treatments respectively, with corresponding residue 15N uptakes of 4 and 8%, while 15N recovery in water stable aggregates (9–15%) was not significantly different. In contrast, when stover was removed and applied before the first crop, yield benefits were highest with cumulative maize yields of 4350 kg ha –1 and residue utilization of 12%. However, N recycling efficiency was not higher than in the early incorporation treatment due to an asynchrony of N release and maize N demand during the first crop. 相似文献
18.
Ján Vojtaššák Dušan Poruban Dušan Bakoš L’udovít Danihel Miroslav Korbel’ L’uboš Danišovič Daniel Böhmer Angelika Danihelová Peter Michalka Branislav Vojtaššák Milan Blaško Milan Blaško Sr. 《Biologia》2006,61(6):713-718
The use of in vitro prepared biosynthetic grafts can considerably improve the patient’s quality of life. This work reports on the use of an autologous
graft prepared from a patient’s preputial cells cultivated on biodegradable polymeric membrane. Coladerm membrane is based
on the chemically modified polyelectrolyte complex of atelocollagen and hyaluronan. The graft was used to cover a defect in
the mouth cavity base and tongue after reconstruction surgery performed at this site in the past. The presented clinical case
showed that the autologous biosynthetic graft prepared from foreskin cells can be successfully used for covering of medium-size
defects in mouth cavity base resulting in the regeneration of target mouth structures with significant improvement of patient’s
quality of life. 相似文献
19.
缓/控释肥料研究进展 总被引:22,自引:0,他引:22
缓/控释肥料对作物产量的影响因作物种类、肥料种类和试验条件而异,大多数植物增产比较明显,如大豆使用长效尿素,与普通尿素相比增产幅度最高可达33%。各种类型的缓/控释肥料,均可不同程度的提高肥料利用率。缓/控释肥料在农业上的应用能有效地保护生态环境,如抑制土壤NH4 向NO3-氧化,减少土壤NO3-的积累,从而减少氮肥以NO3-形式淋溶损失,减少了施肥对环境的污染;可以减少土壤N2O的释放等。提出了目前缓/控释肥料在农业应用中存在的问题及今后的发展方向。 相似文献
20.
生物法合成3-羟基丙酸的研究进展 总被引:1,自引:0,他引:1
从3-羟基丙酸的性质出发,介绍了生物法合成3-羟基丙酸以及它在生物体内的五种代谢途径,此外还简要介绍了3-羟基丙酸在合成生物聚酯、抗植物病虫害上的一些应用。 相似文献