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1.
Two isochinoline alkaloids, glaucine and oxoglaucine were investigated for their suggested anti-inflammatory influence concerning nitric oxide and cytokine production. Mouse peritoneal macrophages were stimulated with different Toll-like receptor (TLR) ligands such as LPS for TLR4, zymosan for TLR2 and CpG for TLR9. The alkaloids inhibited TNF-α and IL-6 production induced by these ligands. In regard to IL-12 suppressive effect was registered in the case of CpG stimulation. Glaucine succeeded to enhance LPS and zymosan-induced IL-10 production. The reduction of pro-inflammatory cytokines and increase of anti-inflammatory IL-10 are indicative for their use in different acute and chronic inflammatory diseases.  相似文献   
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为探索喷钛对甜叶菊叶片中糖苷、甜菊苷(St)和莱鲍迪苷A(RA)的含量、积累量及其比例的影响,为中药材的施肥提供科学依据,应用盆钵培养方法,在甜叶菊生长前期和中期进行叶面喷钛。结果表明:菊隆5号的最佳喷施区间12.22~19.36 mg·kg-1,在喷钛浓度为19.36 mg·kg-1时含量达到最高;新品种2号的最佳喷施区间为12.10~16.71 mg·kg-1,在喷钛浓度为16.71 mg·kg-1时含量达到最高;喷钛后新品种2号St所占比例的最高增幅为156.71%,菊隆5号St的最高增幅为42.28%。喷钛可明显提高糖苷含量和积累总量,与对照相比,差异显著;经回归发现糖苷含量或积累量与喷钛浓度间存在二次曲线关系,相关极显著;喷钛可以增加2个品种糖苷中St的比例。  相似文献   
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建立了香蕉中吡虫啉和高效氯氰菊酯多残留分析方法。样品经1%乙酸乙腈提取,N-丙基乙二胺(PSA)和石墨化炭黑(GCB)净化,以甲醇和2mmol/L乙酸铵水溶液为流动相,进行梯度洗脱分离,采用电喷雾正离子源模式(ESI+),多反应监测(MRM)采集数据,基质匹配外标法定量。吡虫啉和高效氯氰菊酯在0.001~0.1mg/L范围内线性关系良好,相关系数r> 0.9991,方法检出限(LOD)为1 pg,定量限(LOQ)为0.01 mg/kg。在0.01、0.05、0.10 mg/kg3个添加水平下,吡虫啉和高效氯氰菊酯在香蕉中的回收率为84.91%~104.78%,相对标准偏差(RSD)为1.23%~9.69%。该法操作简单、灵敏度高、重现性好,适用于香蕉中吡虫啉和高效氯氰菊酯的残留量测定。  相似文献   
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Veterinary teaching hospitals (VTHs) are facing more and greater challenges than at any time in the past. Changes in demand, expanding information, improving technology, an evolving workforce, declining state support, and an increasingly diverse consumer base have combined to render many traditional VTH modes of operation obsolete. In pursuit of continued success in achieving their academic mission, VTHs are exploring new business models, including innovative collaborations with the private sector. This report provides details on existing models for public-private collaboration at several colleges and schools of veterinary medicine, including those at Kansas State University, Purdue University, the University of Florida, and Tufts University. Although each of these institutions' models is unique, several commonalities exist, related to expansion of the case load available for teaching, the potential positive impact on recruitment and retention of clinical faculty, and the potential for easing financial pressures on the associated VTH. These new models represent innovative approaches that work to meet many of the key emerging challenges facing VTHs today.  相似文献   
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‘无籽’瓯柑Citrus suavissima ‘Seedless’是野生型瓯柑Citrus suavissima的芽变,其花粉完全败育,败育起始于小孢子母细胞减数分裂形成四分体时期。研究‘无籽’瓯柑小孢子母细胞减数分裂异常的分子机制,有利于深入认识果树芽变的发生机制。随机选择“无籽”瓯柑和瓯柑各3株,根据花蕾直径采集花粉母细胞时期(Ⅰ),四分体时期(Ⅱ),单核花粉粒时期(Ⅲ),双核花粉粒时期(Ⅳ)及花粉粒成熟期(Ⅴ)共5个时期的花蕾并分离花药,利用实时荧光定量聚合酶链式反应(qRT-PCR)分析减数分裂特性基因RAD51和MS1的相对表达量,3次重复。通过SPSS 16.0的最小显著差法(LSD)在0.01水平上进行各样品间的相对表达量差异分析。结果表明:RAD51和MS1基因的表达高峰均集中在第Ⅰ时期和第Ⅱ时期,且此时花药中的相对表达量均极显著(P<0.01)高于花蕾。第Ⅰ时期花药中,‘无籽’瓯柑RAD51的相对表达量为瓯柑的3.7倍,MS1可达300倍;但同时期花蕾中,RAD51的相对表达量仅1.1倍,MS1为140.0倍。‘无籽’瓯柑RAD51基因在第Ⅰ时期和第Ⅱ时期的相对表达量极显著(P<0.01)高于瓯柑,说明‘无籽’瓯柑小孢子母细胞和四分体时期的细胞内均存在DNA受损现象;‘无籽’瓯柑MS1基因在第Ⅰ时期的相对表达量极显著(P<0.01)高于瓯柑,但第Ⅱ时期极显著(P<0.01)低于瓯柑,推测‘无籽’瓯柑败育花粉的形成与MS1基因表达紊乱引起油脂分泌、转运异常密切相关。图6表1参24  相似文献   
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In this work, the effects of various operating parameters (pressure, pH, BPA concentration, and filtration time) toward bisphenol A (BPA) removal via ultrafiltration (UF) membrane system were investigated using response surface methodology (RSM). Historical data design of RSM was used to obtain the interaction between variables and response as well as optimizing the process. The analysis of variance (ANOVA) showed that the third-order polynomial model was significant in which pH and filtration time were identified as significant terms that influence BPA removal. The 3D response surface plots revealed the two-factor interaction between independent and dependent variables. The optimization process of the model predicted optimum conditions of 99.61% BPA removal at 1 bar, pH 6.7, 10 μg/L BPA concentration, and 10-min filtration time. The predicted optimum conditions for BPA removal were consistent with the obtained experimental values, indicating reliable application of historical data design RSM for modeling BPA removal in UF membrane system.  相似文献   
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为滇中高原亚热带森林资源的保护与可持续利用提供依据,对玉溪磨盘山即元江栲半湿润常绿阔叶林、云南松次生混交林、天然华山松林和高山矮栎林4种植被类型的凋落物及其土壤(0~10cm)进行收集、取样测定其C、N、P含量及化学计量比,分析不同植被类型的凋落物和土壤养分之间的关系。结果表明:1)4种植被类型在凋落物的未分解层C含量,以云南松次生混交林最高,达624.04g/kg,华山松林最低,为475.76g/kg;N含量以常绿阔叶林最高,为15.49g/kg,华山松林最低,为12.2g/kg;P含量以华山松林最高,为2.3g/kg,常绿阔叶林最低,为1.91g/kg。4种植被类型凋落物半分解层N、P含量差异不显著,C含量以云南松次生混交林最高,为337.38g/kg,华山松林最低,为211.96g/kg。表层土壤C、N、P含量差异显著,均表现出云南松次生混交林最高,华山松林最低。2)4种植被类型凋落物未分解层中,C/N值以云南松混交林最小,C/P、N/P值均以高山栎林最小;半分解层中4种植被类型N/P值无显著差异,而C/N、C/P值均以常绿阔叶林为最大;表层土壤层中C/N、C/P和N/P值均无显著差异。3)高山栎林凋落物的N含量未分解层与其半分解层呈显著正相关。常绿阔叶林凋落物未分解层N含量与其半分解层中N、P含量均呈显著正相关。华山松林凋落物未分解层C含量与其表层土壤层C含量呈显著相正相关。云南松混交林未分解层N含量与其土壤层P含量呈显著正相关。  相似文献   
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