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1.
从食用菌种类及其分布、产值、食用菌企业、食用菌产业循环经济发展情况等方面介绍了粤北地区食用菌产业发展现状,总结食用菌产业发展中存在的问题,如菌种问题突出,品牌意识缺乏;食用菌产业标准化落后;产品质量参差不齐,食品质量安全无保障;资源浪费严重;精深加工不足等,并提出相应的对策。  相似文献   
2.
筛选出适合配制烟剂的高效药剂,用低成本的供热剂,采用简便、安全的干制法配成复方棚菌灵烟剂,可防治温室、塑料大棚黄瓜、番茄的多种病害,具有高效、经济、低毒、对蔬菜污染小、便于推广应用等特点.  相似文献   
3.
Functional brain alterations induced by lindane were examined in Rat chronically exposed to low doses of lindane (1 and 2 μg L−1 in drinking water) from conception. Histological and electrophysiological investigations were conducted at 14 weeks of age. Lindane did not induce histological changes. It did not significantly modify the sleep-wakefulness cycle and EEG did not show major alterations. The spectral EEG analysis, by recording cortical variations in both energy spectrum and energy levels of different frequency bands, showed an increase in the 11-15 Hz activity in both groups exposed to lindane. This activity was characterised by spindles well-depicted during slow wave sleep or associated with fast activity during wakefulness and theta activity in paradoxical sleep. These data suggest that chronic exposure to lindane doses as low as 1 μg L−1 in drinking water could lead to central electrophysiological effects possibly involving GABA-benzodiazepine mechanisms.  相似文献   
4.
马铃薯渣酶法水解液制备单细胞蛋白饲料的研究   总被引:1,自引:0,他引:1  
本文研究了酶法水解马铃薯渣制备膳食纤维后的滤液制备单细胞蛋白的可行性。试验结果表明,单细胞蛋白边糖化边发酵的摇瓶培养的较优工艺条件为:底物浓度为8%(添加8%的麸皮水)、初始pH值为4.5、接种量为15%、葡萄糖淀粉酶加入量为100U/g(原料中淀粉)、青霉素加入量为80U/g(原料)、培养温度为28℃、培养时间为6h、转速为250r/min。在此条件下,干酵母产量最高为19.920g/L,单细胞蛋白中的蛋白质含量达12.27%。  相似文献   
5.
AIM:To investigate the effect of LY980503(a benflumetol derivative)on multidrug resistance of tumor cell line using DNA microarray.METHODS:Total RNA was extracted from multidrug resistant MCF/DOX cell line. cDNA microarray containing 320 cDNAs was used to detect the gene expression profile.RESULTS:9 down-regulated genes and 1 up-regulated gene were identified after multidrug resistant MCF/DOX cells were treated with LY980503.CONCLUSION:LY980503 can effectively reverse the resistance of MCF/DOX to DOX in vitro by adjusting the expression of multi-genes.  相似文献   
6.
AIM:To investigate whether the bcl-2 antisense oligonucleotide increases the sensitivity of HL60 and K562 cell lines to daunorubicin.METHODS:IC50 for HL60 and K562 was determined with MTT method, the expression levels of Bcl-2 protein were assayed by immunofluorescence using fluoresce isothiocyanate labeling. In addition, apoptosis was detected by morphological observation and flow cytometric analysis of DNA fragmentation.RESULTS:It was found that the two oligonucleotides directed against the coding region and the translation initiation of bcl-2 mRNA, combined respectively with daunorubicin, inhibited expression of bcl-2 protein, increased apoptosis in HL60 and K562 cells, and decreased IC50 of daunorubicin significantly (P<0.05). Compared to the antisense oligonucleotide directed against the translation initiation of bcl-2 mRNA, the antisense oligonucleotide directed against the coding region showed stronger effects in the aspects of increasing the sensitivity of HL60 cells to daunorubicin (P<0.05).CONCLUSIONS:These two antisense sequences in the translation initiation and the coding region of bcl-2 mRNA increased the sensitivity of HL60 and K562 cell lines to daunorubicin in a sequence-specific manner.  相似文献   
7.
AIM: To investigate the effect of Chinese herbs, Ganxianfang(GXF), on rat hepatic stellate cells (HSC) proliferation and collagen synthesis. METHODS: Two types of herb serum, portal venous serum and circumferential venous serum, were prepared from rats infused intragastrically with 16, 8, 4 times adult dose of GXF decoction. HSC isolated from rat liver were processed with the above sera in vitro. Then we mensurated the radioactivity of HSC admixed with [[3H]H]proline and [[3H]H]thymine to judge the effect on proliferation and collagen synthesis of HSC. RESULTS: Both two types of serum collected 0.5, 1, 2 h after intragastrical infusion inhibited HSC proliferation (P<0.05), and the serum collected 1 h after intragastrical infusion had the strongest effect (P<0.05). Portal serum decreasea collagen synthesis (P<0.05), but circumferential serum had no effect (P>0.05). CONCLUSION: Inhibition of HSC proliferation and decrease of collagen synthesis may contribute to the GXF antifibrotic action.  相似文献   
8.
我国农药残留快速检测技术的研究与应用现状   总被引:21,自引:1,他引:21  
本文简述了目前农药残留快速检测技术的研究概况,分析了农药残留快速检测技术在我国的实际应用情况。  相似文献   
9.
生物传感器在农药残留分析中的应用   总被引:13,自引:0,他引:13  
本文简要介绍了几类生物传感器(酶传感器、微生物传感器、免疫传感器及压电传感器)在农药残留分析中的应用进展,并探讨了其发展趋势。  相似文献   
10.
免疫亲合色谱及在农药残留分析中的应用   总被引:7,自引:0,他引:7       下载免费PDF全文
免疫亲合色谱可用于复杂样本中微量目标分析物的选择性分离富集。综述了免疫亲合色谱的基本原理、方法的建立过程(包括抗体的制备、固相基质的筛选、抗体与基质的偶联、免疫亲合色谱条件的优化)、免疫亲合色谱在农药残留分析中的应用现状及发展趋势。  相似文献   
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