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排序方式: 共有9010条查询结果,搜索用时 281 毫秒
931.
932.
本试验旨在研究基于不同地区取样点土壤成分条件下,木质素降解菌的生长特性,并为筛选出降解农作物秸秆中木质素的优势菌奠定基础.通过对扬州、南京、临沂、潍坊和连云港地区5个取样点的土壤成分测定,并利用选择培养基和马铃薯葡萄糖琼脂(PDA)-RB亮蓝与PDA-Bavendamm平板显色反应鉴定不同土壤中木质素降解菌生长量及其木质素降解酶特性,依据各取样点菌株的生长特性最终选择优势菌株.结果表明,扬州取样点土壤中木质素降解菌密度[(5.67±0.58) 105g-1]极显著高于另外4个取样点(P<0.01),所获得的木质素降解菌的产酶特性亦优于其他取样点.可知,5个取样点土壤中木质素降解菌密度存在明显差异,并与土壤中总有机碳含量呈强正相关(r=0.84,P<0.01). 相似文献
933.
《Journal of Crop Improvement》2013,27(1):337-347
Summary This paper summarizes the conception and development of microbial fertilizers and inoculants in China that are used to improve soil quality and the growth, yield and protection of crops. The results presented show the relative effects of these microbial products applied singly or with chemical fertilizers on soil fertility, crop yield and protection. The paper discusses current trends in the development and use of microbial fertilizers in China and suggests areas of high priority research. 相似文献
934.
Alejandro M. S. Mayer Abimael D. Rodríguez Orazio Taglialatela-Scafati Nobuhiro Fusetani 《Marine drugs》2013,11(7):2510-2573
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories. 相似文献
935.
Wenxia Sun Cuiting Lv Tonghan Zhu Xue Yang Shanjian Wei Jieyin Sun Kui Hong Weiming Zhu Caiguo Huang 《Marine drugs》2013,11(11):4570-4584
Multidrug-resistance is a major obstacle facing cancer chemotherapy. This paper demonstrates that novel compound Ophiobolin-O reverses MCF-7/ADR resistance to adriamycin (ADM). The IC50 of ADM treated MCF-7 cells was 2.02 ± 0.05 µM and 74.00 ± 0.18 µM treated MCF-7/ADR cells, about 37-fold, compared to the former. However, 0.1 µM Ophiobolin-O (less than 20% inhibition concentration) combined with ADM caused the decreased IC50 of ADM to 6.67 ± 0.98 µM, indicating it reversed ADM resistance of MCF-7/ADR cells (11-fold). Furthermore, Ophiobolin-O increased ADM-induced mitochondrial pathway apoptosis and G2/M phase arrest, which is partly due to the elevation level of ROS in MCF-7/ADR cells. As we described in this paper, the reversal effect of Ophiobolin-O may be due to the reduction of resistance-related protein P-Glycoprotein (P-gp, also known as MDR1) through inhibiting the activity of the multidrug resistance 1 (MDR1) gene promoter, which makes MCF-7/ADR cells more sensitive to ADM treatment. Assays in nude mice also showed that the combination of ADM and Ophiobolin-O significantly improved the effect of ADM. 相似文献
936.
Marine natural products are a diverse, unique collection of compounds with immense therapeutic potential. This has resulted in these molecules being evaluated for a number of different disease indications including the neglected protozoan diseases, human African trypanosomiasis and Chagas disease, for which very few drugs are currently available. This article will review the marine natural products for which activity against the kinetoplastid parasites; Trypanosoma brucei brucei, T.b. rhodesiense and T. cruzi has been reported. As it is important to know the selectivity of a compound when evaluating its trypanocidal activity, this article will only cover molecules which have simultaneously been tested for cytotoxicity against a mammalian cell line. Compounds have been grouped according to their chemical structure and representative examples from each class were selected for detailed discussion. 相似文献
937.
938.
A. Gefrom E. M. Ott S. Hoedtke A. Zeyner 《Journal of animal physiology and animal nutrition》2013,97(6):1152-1160
Ensiling legume grain may be an inexpensive and ecologically interesting method to produce a high‐protein feed of local origin. The typically patchy maturation recommends harvesting and ensiling the seeds in moist condition. Developing a method for preserving legume grains harvested before maturation by lactic acid fermentation would have several advantages. Under laboratory conditions, crushed legume seeds of beans, peas and lupines with high moisture content of 35 % were ensiled with different additives (molasses and lactic acid bacteria). To characterize the final silages, contents of proximate nutrients and antinutritional factors (alkaloids, oligosaccharides, tannins) were analysed. The addition of lactic acid bacteria ensured a fast and pronounced lactic acid production and decreased contents of undesired fermentation products like ethanol. An additional use of molasses for ensilage did not provide a remarkable additional benefit. Excluding sugar and starch, the contents of proximate nutrients were not remarkably altered after ensiling. As an overall effect, lactic acid fermentation reduced tannins and oligosaccharides. It can be supposed that the oligosaccharides after breakdown of the complex molecules acted as a source of fermentable carbohydrates. A relevant reduction of alkaloids did not occur. The lactic acid fermentation of legume grains can be recommended as an appropriate method for conservation. With respect to the economic advantages and compared with methods of chemical preservation, the lactic acid fermentation of legume grains under anaerobic conditions is an environmentally compliant procedure and therefore also an option for organic farming. 相似文献
939.
高效液相色谱法测定鱼、虾和鸡肉中的呋喃唑酮残留 总被引:1,自引:0,他引:1
建立高效液相色谱(HPLC)法测定鱼、虾和鸡肉中呋喃唑酮药物残留量的方法.色谱条件为Kro-masil C18(250 mm×4.6 mm,5 μm)柱,流动相乙腈-0.1%磷酸水溶液(30∶70,V/V),流速1.0 mL/min,检测波长365 nm,柱温25℃.结果表明,呋喃唑酮标准溶液在0.2~5.0 ng范围内与峰面积呈良好的线性关系(r=0.999 1),检出限为0.2 μg/kg(S/N=3).样品平均加标回收率为97.7%~102.9%,RSD为1.1%~1.5%(n=6).该方法简单、快速、灵敏度高、重复性好,适用于鱼、虾和鸡肉中呋喃唑酮的残留分析. 相似文献
940.