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为了发掘具有耐高温特性的昆虫病原线虫,本实验室对在山东地区采集的122份土样进行了线虫分离,得到异小杆线虫JNR,扩增其ITS基因和D2-D3基因,并构建系统进化树,分析可得:线虫JNR与嗜菌异小杆线虫Heterorhabditis bacteriophora在同一分支,同源性达到98%以上,为嗜菌异小杆线虫品系。为进一步了解该线虫品系的生物学特性,本试验研究了其侵染力、高温耐受力及水平运动能力。结果表明,线虫JNR有较好的耐热性,38℃条件下处理16 h,存活率最高54%,24 h时为32%;40℃水浴处理2 h,低浓度500 IJs/mL下存活率28%,3 h后全部死亡。对大蜡螟和小菜蛾的生测结果显示,在10、15、20、25、30、35、40、60、120、240 IJs/头剂量下处理24 h,蔬菜害虫小菜蛾先出现死亡,大蜡螟则在48 h后出现死亡;大于20 IJs/头剂量下,处理48 h后线虫对大蜡螟的校正死亡率达到59.5%,高于对小菜蛾的侵染效果。在剂量120 IJs/头以上,72 h后寄主的校正死亡率均能达到100%。异小杆线虫JNR在30℃条件下水平运动能力比在18、25℃时强,48 h时有31%的个体运动到3.6 cm处。以上研究表明,该线虫有较强的侵染力,特别是在温度相对较高时具有较好的耐热力和水平运动能力,对防治蔬菜田小菜蛾具有应用开发潜力。 相似文献
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Yuval Ramot Michal Steiner Yossi Lavie Nati Ezov Orgad Laub Eran Cohen Yotam Schwartz Abraham Nyska 《Journal of toxicologic pathology》2021,34(4):319
Bleeding during surgical procedures is a common complication. Therefore, hemostatic agents have been developed to control bleeding, and fibrin sealants have several benefits. sFilm-FS is a novel fibrin sealant that comprises a biodegradable co-polymeric film embedded with human fibrinogen and thrombin. Herein, the safety and efficacy of sFilm-FS were compared using a liver and spleen puncture model of Göttingen minipigs with those of the standard hemostatic techniques (control animals) and EVARREST®, a reference fibrin sealant. Hemostasis and reduced blood loss were more effectively achieved with sFilm-FS than with the standard techniques in the control animals and comparable to those achieved with EVARREST®. No treatment-related adverse effects were observed in any of the groups. Histopathological evaluation indicated that sFilm-FS was slightly and moderately reactive at the liver puncture site and spleen, respectively, compared with the standard techniques in the control animals. These changes are expected degradation reactions of the co-polymeric film and are not considered as adverse events. No treatment-related abnormalities were noted in the other evaluated organs. Additionally, no evidence of local or systemic thromboses was noted. These results support the use of sFilm-FS for hemostasis in humans. 相似文献
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ZHANG Xue-wen LI Hong-ya QI Cong-yan WANG Shu-xiang WANG Quan LI Shu-na 《中国畜牧兽医》2017,44(8):2319-2325
The aim of this study was to select a strain of producing mannase Bacillus, and investigate its effects on growth performance of geese. Congo red plate changing color circle method and assay of enzyme activity method in liquid fermentation were used in screen and rescreen,respectively. Animal safety and gastrointestinal tolerability tests were alse carried out. By morphological observation,physiological and biochemical tests,analysis of complete sequence of 16S rDNA and the phylogenetic tree establishment,species were identified. Bacillus were prepared and added by 0.10%, 0.25%, 0.50%, 0.75% and 1.00% in the geese diets to study its effect on the daily gain and F/G in geese. The results showed that the enzyme activity of the isolated Bacillus subtilis Y-3-2 was 45.939 U/mL, and the strain could also endure pH 2.0 and grow normally in 0.1% cholic acid salt solution and artificial intestinal fluid. The results of feeding test showed that, compared to the control group, the average daily gain of geese increased by 8.78%(P<0.01) and F/G decreased by 6.69% (P<0.01) by adding 0.25% Y-3-2 preparation. In conclusion, adding mannase producing Bacillus could improve the feed utilization and growth of geese. 相似文献
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为了筛选一株产甘露聚糖酶的芽孢杆菌,并考察其对肉鹅生长性能的影响,本试验采用刚果红平板变色圈法进行产甘露聚糖酶芽孢杆菌的初筛,通过液体发酵测定酶活力的方法展开复筛,并进行动物安全性和胃肠道耐受性试验。通过形态特征观察、生理生化试验和16S rDNA全序列分析与发育树构建将其鉴定到种。制备该菌菌剂,并将其按0.10%、0.25%、0.50%、0.75%和1.00%添加于肉鹅日粮中,考察其对肉鹅日增重和料重比的影响。结果表明：筛选到产甘露聚糖酶的菌株枯草芽孢杆菌（Bacillus subtils） Y-3-2,其产酶活力为45.939 U/mL,耐受pH 2.0,在0.1%的胆酸盐溶液和人工肠液中可正常生长。将其制成菌剂,在肉鹅日粮中按0.25%添加,可使试验组肉鹅日增重较对照组提高8.78%（P<0.01）,料重比降低6.69%（P<0.01）。以上结果说明在肉鹅日粮中添加本试验筛选出的产甘露聚糖酶芽孢杆菌可提高肉鹅的饲料利用率,对肉鹅的生长有显著促进作用。 相似文献
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不同光温敏核不育水稻对低温耐受度的差异比较研究 总被引：1，自引：0，他引：1
【目的】探讨光温敏核不育水稻低温耐受度的影响因素,为选育不育性稳定的光温敏核不育水稻提供理论依据。【方法】以光温敏核不育水稻籼S、N28S、安农S、培矮64S、N9S、N2S为材料,利用人工气候箱对处于育性敏感期的各不育系分别进行持续3、7、10 d 的21和23 ℃低温处理,通过调查花粉育性来研究各不育系对短期低温的耐受度差异。【结果】各不育系对低温耐受程度的强弱次序为：籼S、N28S>安农S>培矮64S>N9S、N2S。其中无花粉型不育系籼S、N28S、安农S低温处理3 d时花粉均为不育;持续7 d时,除安农S出现可育花粉外,籼S、N28S花粉育性均为0;持续10 d时,安农S的花粉可育率高于持续7 d的处理,并且籼S和N28S转为可育;典败型不育系培矮64S、N9S、N2S经过持续3、7、10 d的低温处理,除培矮64S经23 ℃低温处理3 d的花粉不育外,其他均出现可育花粉,且花粉的可育程度随着低温处理时间的延长和低温强度的加大而增强。【结论】光温敏核不育系对短期低温的耐受度除与不育临界温度有关外,还可能与花粉败育方式有关,低不育临界温度的无花粉型不育系的不育性较稳定。在实用型光温敏核不育水稻的选育过程中,可多关注低不育临界温度的无花粉型不育系选育。 相似文献
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This paper presents an assessment system which on the basis of quantifiable criteria and appropriate orientation values describes the risk potentials of farming as far as environmental protection and sustainability is concerned. The procedure addresses the most significant risks and suggests ranges for their tolerability. By this way farmers can recognize principal shortcomings of their management and look for appropriate countermeasures to cope with them. The guiding principle is a way of farming which uses the available resources and the production potential as efficiently as possible, while keeping the unfavorable impacts on soils, water, air and biota within acceptable limits. Several years of investigations in about 125 different farms have shown that non‐tolerable impacts of farming on the environment are predominantly due to avoidable managerial mistakes. The suggested assessment system provides criteria for the actual magnitude and the tolerability of the different risk potentials and may thus help to substantiate the compliance with such general principles as ”︁good farming practice”. 相似文献
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[目的]探讨光温敏核不育水稻低温耐受度的影响因素,为选育不育性稳定的光温敏核不育水稻提供理论依据.[方法]以光温敏核不育水稻籼S、N28S、安农S、培矮64S、N9S、N2S为材料,利用人工气候箱对处于育性敏感期的各不育系分别进行持续3、7、10 d的21和23℃低温处理,通过调查花粉育性来研究各不育系对短期低温的耐受度差异.[结果]各不育系对低温耐受程度的强弱次序为:籼S、N28S＞安农S＞培矮64S＞ N9S、N2S.其中无花粉型不育系籼S、N28S、安农S低温处理3d时花粉均为不育;持续7d时,除安农S出现可育花粉外,籼S、N28S花粉育性均为0;持续10 d时,安农S的花粉可育率高于持续7d的处理,并且籼S和N28S转为可育;典败型不育系培矮64S、N9S、N2S经过持续3、7、10 d的低温处理,除培矮64S经23℃低温处理3d的花粉不育外,其他均出现可育花粉,且花粉的可育程度随着低温处理时间的延长和低温强度的加大而增强.[结论]光温敏核不育系对短期低温的耐受度除与不育临界温度有关外,还可能与花粉败育方式有关,低不育临界温度的无花粉型不育系的不育性较稳定.在实用型光温敏核不育水稻的选育过程中,可多关注低不育临界温度的无花粉型不育系选育. 相似文献
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