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1.
为了解呕吐毒素(DON)、玉米赤霉烯酮(ZEN)和黄曲霉毒素B1(AFB1)在2020年底新玉米中的污染情况,指导饲料生产企业和养殖场(户)开展霉菌毒素防控,降低霉菌毒素对饲料质量安全及养殖动物的影响,避免经济受损的风险。2020年12月在市场上采集新玉米样本225份,采用胶体金免疫层析法或上转发光免疫分析法对其霉菌毒素污染情况进行检测,依据安佑集团相关企业标准标和GB 13078-2017《饲料卫生标准》进行判定分析。结果表明:新玉米中霉菌毒素检出率为96.0%,其中DON、ZEN和AFB1的检出率分别为85.8%、87.1%和86.7%|DON、ZEN和AFB1在新玉米中的污染状况差别较大,按《饲料卫生标准》判定的超标率分别为0.0%、0.4%和11.6%|最大检测值分别为2500、534 μg/kg和>100 μg/kg。就产地而言,山西、内蒙古、东北、安徽、山东、河南、云南、陕西等地霉菌毒素污染较重。综上,与2019年及2020年玉米霉菌毒素污染调查数据相比,2020年底新玉米污染程度较重。 [关键词] 玉米|霉菌毒素|胶体金免疫层析法|上转发光免疫分析法|污染规律  相似文献   
2.
Mycotoxic nephropathy was induced in 18 young pigs by diets contaminated with strains of Aspergillus ochraceus containing ochratoxin A (OTA) and penicillic acid (PA) at levels corresponding to those naturally encountered in animal feeds in Bulgaria. Haematological and biochemical parameters, as well as the morphological and ultrastructural changes in various internal organs, and especially in the kidneys, were examined at different stages of development of the disease. A mottled surface of the kidneys was only seen in pigs exposed to a mouldy diet containing 180 ppb OTA for 3 months, but microscopic lesions, as well as changes in various haematological and biochemical parameters, were observed in all groups exposed to the same mouldy diet containing only 90 or 180 ppb OTA. Histological examination showed two types of change: degenerative changes affecting the epithelial cells of the proximal tubules, which predominated at the initial stage, and proliferative changes in the interstitium, which predominated at the later stage of the disease. Telangiectasis and lymph stasis were also seen, as well as degenerative changes in the capillary endothelium. The characteristic renal lesions were similar to those observed in spontaneous cases of mycotoxic porcine nephropathy in Bulgaria, but they were a little different from the classic Danish porcine nephropathy. The enhanced toxicity of OTA in our study may be due to a synergistic effect between OTA and PA or to some other unknown metabolites produced by the same ochratoxinogenic strains of A. ochraceus.  相似文献   
3.
Breeding wheat and rye for resistance to Fusarium diseases   总被引:6,自引:1,他引:6  
T. Miedaner 《Plant Breeding》1997,116(3):201-220
Fusarium culmorum and F. graminearum Groups 1 and 2 cause seedling blight, crown rot, foot rot and head blight in wheat and rye that may affect grain yield and quality for baking and feeding. This review starts with an analysis of Fusarium populations with regard to their genetic variation for aggressiveness, mycotoxin production, and isolate-by-host genotype interaction. To assess resistance in the different host growth stages, quantitative inoculation and disease assessment techniques are necessary. Based on estimated population parameters, breeding strategies are reviewed to improve Fusarium resistance in wheat and rye. Epidemiological and toxicological aspects of Fusarium resistance that are important for resistance breeding are discussed. F. culmorum and F. graminearum display large genetic variation for aggressiveness in isolate collections and in naturally occurring populations. The production of mycotoxins, especially deoxynivalenol and its derivatives, is a common trait in these populations. Significant isolate-by-host genotype interactions were not found across environments in wheat and rye. Artificial infections in the field are indispensable for improving Fusarium crown rot, foot rot and head blight resistance in wheat and rye. For a reliable disease assessment of large populations, disease severity ratings were found to be the most convenient. The differentiation of host resistance is greatly influenced by an array of nongenetic factors (macro-environment, microclimate, host growth stage, host organ) that show significant interactions with host genotype. Selection for environmentally stable resistance has to be performed in several environments under a maximum array of different infection levels. Selection in early growth stages or on one plant organ does not in most cases allow prediction of resistance in adult-plant stages or another plant organ. Significant genetic variation for resistance exists for all Fusarium-incited diseases in breeding populations of wheat and rye. The patho-systems studied displayed a prevalence of additive gene action with no consistent specific combining ability effects and thus rapid progress can be expected from recurrent selection. In wheat, intensive testing of parental genotypes allows good prediction of the mean head blight resistance after crossing. Subsequent selection during selfing generations enables the use of transgression towards resistance. In hybrid breeding of winter rye, the close correlation between foot rot resistance of inbred lines and their GCA effects implies that selection based on the lines per se should be highly effective. This is not valid for F. culmorum head blight of winter rye caused by a greater susceptibility of the inbred lines compared to their crosses. For both foot rot and head blight resistance, a high correlation between the resistance to F. graminearum and F. culmorum was found in wheat and rye. Mycotoxin accumulation occurs to a great extent in naturally and artificially infected plant stands. The correlation between resistance traits and mycotoxin contents are medium and highly dependent on the environment. Further experiments are needed to clarify whether greater resistance will lead to a correlated reduction of the mycotoxin content of the grains under natural infection.  相似文献   
4.
During the last century, as the area of wheat grown under advanced grain husbandry has increased worldwide, so too has the importance of Fusarium ear scab (FES) (synonym, Fusarium head blight) caused by several species of the fungus Fusarium. Yield losses due to FES can total 20%-40% and more depending on climatic conditions. During the last twenty years epidemics of FES in cereals have become chronic all over the world, including the United States and Russia. The most destructive of t…  相似文献   
5.
The effects of age of ascospores (0–18 days after discharge), photon flux density (0–494 mol m–2 s–1 PAR), temperature (4–30 °C), frost (–15 °C for 30 min), relative humidity (RH; 0–100%), pH (2.5–6.5) and dryness (0 and 53% RH for up to 40 min) on the germination of the ascospores of the mycotoxin-producing fungus Gibberella zeae (anamorph Fusarium graminearum) were studied. Freshly discharged ascospores germinated within 4 h at 20 °C and 100% RH. The rate of germination and the percentage of viable ascospores decreased over time after the spores were discharged from perithecia. The time course of ascospore germination was not significantly affected by photon flux density. The period of time required to obtain 50% germinated ascospores at 100% RH was 26.90 h at 4 °C, 10.40 h at 14 °C, 3.44 h at 20 °C and 3.31 h at 30 °C. There was no significant effect of frost on the percentage of viable ascospores. A small percentage (6.6 ± 3.8%) of the ascospores germinated at 53% RH. At RH 84% and 20 °C almost 100% of the freshly discharged ascospores germinated. The time course of ascospore germination was affected by pH. The maximum rate of ascospore germination was estimated to be at pH 3.76. Ascospores lost their ability to germinate following exposure to 0% RH almost instantaneously. No germinating spores were detected after an incubation period of 1 min at 0% RH. Incubating the ascospores at 53% RH decreased the percentage of viable spores from 93 to 6% within 10 min. The data demonstrate that age of spores, relative humidity, temperature and pH, but not photon flux density, are key factors in germination of G. zeae ascospores.  相似文献   
6.
本试验旨在研究自然霉变玉米对断奶仔猪生长性能、肝脏结构与功能的影响,并初步探讨甘露寡糖可能的缓解作用。试验采用2×2因子设计,20头体重(8.10±0.32)kg的35日龄PIC断奶仔猪随机分为4组,分别饲喂添加不同水平霉变玉米(0、100%)和甘露寡糖(0、0.2%)的饲粮。结果表明:霉变玉米组仔猪全期平均日增重(P<0.01)和平均日采食量显著降低(P<0.05);肝细胞发生严重颗粒和空泡变性,肝脏丙二醛含量显著升高(P<0.05)和Bax mRNA表达量极显著升高(P<0.01)。添加甘露寡糖极显著提高仔猪肝脏总抗氧化力(T-AOC)(P<0.01),缓解霉变玉米导致的肝脏病理损伤,且霉变玉米与甘露寡糖对T-AOC的影响具有显著的交互效应(P<0.01)。由此可见,自然霉变玉米降低仔猪生长性能,诱导肝脏氧化应激并损伤肝脏结构;添加甘露寡糖对自然霉变玉米导致的肝损伤有一定程度的缓解作用。  相似文献   
7.
饲料霉变严重危害饲料业及畜牧业生产过程。就饲料中几种常见霉菌毒素的危害及防治措施进行了综述.并主要介绍了以生物防治为主的防治措施,以期为科学认识霉菌毒素和选用防霉剂提供参考依据。  相似文献   
8.
霉菌毒素广泛存在于食品和饲料当中,严重地危害人类和动物的健康。如何有效清除霉菌毒素一直是重要的研究课题。乳酸菌具有多种生物学功能,近年来研究表明,乳酸菌具有清除霉菌毒素能力。为了更好地理解乳酸菌清除霉菌毒素的作用,文章就近年来乳酸菌对霉菌毒素的清除机制加以综述。  相似文献   
9.
镰刀菌毒素对动物毒性作用的研究进展   总被引:1,自引:0,他引:1  
镰刀菌是污染粮食和饲料的主要真菌菌属之一,可产生多种高毒性、低分子量的代谢产物,如玉米赤霉烯酮、脱氧雪腐镰刀菌烯醇、T-2毒素等,这些毒素严重威胁动物和人类的健康。摄入镰刀菌毒素可对动物造成多种毒性作用,包括生殖毒性、免疫毒性、肠道毒性、肝肾毒性、细胞毒性及致癌性等。不同类型镰刀菌毒素引起的毒性作用不尽一致,且不同毒素间存在互作效应。为此,本文对单一或混合镰刀菌毒素毒性的研究进展进行了总结和归纳,为镰刀菌毒素的深入研究提供参考和借鉴。  相似文献   
10.
霉菌毒素是由不同种属真菌产生的次级代谢物,其对多种动物(包括人在内)具有显著毒性效果,如降低畜禽生产性能、损害脏器功能、影响机体免疫功能、造成细胞和DNA氧化损伤,甚至导致动物死亡等。饲料及其原料霉菌毒素污染是一个广泛的、全球性的问题,既可在作物田间生长时产生,也可在仓储期间产生,给畜禽养殖业造成了巨大的经济损失,防控霉菌生长及去除饲料中霉菌毒素已成为国内外研究的热点。实际上,不同霉菌毒素对不同动物的损害具有差异性,而在畜禽养殖过程中添加适当物质(如蒙脱石和酶制剂等)可有效抑制霉菌毒素活性,缓解霉菌毒素的毒性。作者详细论述了玉米赤霉烯酮、烟曲霉毒素、呕吐毒素、T-2毒素、黄曲霉毒素和烟曲霉毒素对畜禽的危害,并从物理、化学、生物角度介绍了削减饲料及其原料中霉菌毒素的方法,旨在为合理有效防控霉菌毒素毒害及保障畜禽健康养殖提供参考。  相似文献   
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