全文获取类型
收费全文 | 256篇 |
免费 | 12篇 |
国内免费 | 18篇 |
专业分类
林业 | 5篇 |
农学 | 34篇 |
基础科学 | 9篇 |
31篇 | |
综合类 | 113篇 |
农作物 | 6篇 |
水产渔业 | 7篇 |
畜牧兽医 | 16篇 |
园艺 | 41篇 |
植物保护 | 24篇 |
出版年
2024年 | 6篇 |
2023年 | 14篇 |
2022年 | 10篇 |
2021年 | 10篇 |
2020年 | 16篇 |
2019年 | 11篇 |
2018年 | 5篇 |
2017年 | 11篇 |
2016年 | 13篇 |
2015年 | 13篇 |
2014年 | 15篇 |
2013年 | 15篇 |
2012年 | 19篇 |
2011年 | 22篇 |
2010年 | 15篇 |
2009年 | 8篇 |
2008年 | 15篇 |
2007年 | 13篇 |
2006年 | 7篇 |
2005年 | 9篇 |
2004年 | 7篇 |
2003年 | 7篇 |
2002年 | 2篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1988年 | 1篇 |
排序方式: 共有286条查询结果,搜索用时 15 毫秒
91.
以‘莱芜大姜’为试材,采用污灌方式研究不同水平铅(Pb)胁迫(土壤Pb 含量分别为0、150、450 和1 350 mg · kg-1)对姜叶片活性氧代谢的影响。结果表明,随Pb 胁迫水平的升高及胁迫时间的延长,姜叶片中生成速率和H2O2 含量显著升高,但过度Pb 胁迫则使其降低,而丙二醛(MDA)含量和电解质渗漏率则持续增加。Pb 胁迫40 d 时,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、谷胱甘肽还原酶(GR)、抗坏血酸过氧化物酶(APX)、单脱氢抗坏血酸还原酶(MDHAR)、脱氢抗坏血酸还原酶(DHAR)等抗氧化酶活性随Pb 胁迫水平的升高显著增强,还原型抗坏血酸(AsA)、总抗坏血酸(AsA + DHA)及还原型谷胱甘肽(GSH)、总谷胱甘肽(GSH + GSSG)等抗氧化物质含量显著升高,AsA/DHA、GSH/GSSG 比值显著增加;随胁迫时间的增加,抗氧化酶活性及抗氧化物质含量则多以150 mg · kg-1 的轻度Pb 胁迫的较高,过度的Pb 胁迫则使其显著降低,表明AsA-GSH 循环遭受严重破坏。 相似文献
92.
93.
Evaluation of the antioxidant and antiteratogenic role of ginger Zingiber officinale polyphenols against the toxicity induced by fenitrothion and/or lead in female albino rats were investigated. Adult virgin females were divided into 8 groups and were orally treated as follow: control (C), 1% w/w of ginger (G), 120 μg/animal lead as lead acetate (L), 10 mg/kg of fenitrothion (F), lead (120 μg/animal) fenitrothion (10 mg/kg) (LF), ginger (1%w/w) + fenitrothion (10 mg/kg) (GF), ginger (1%w/w) + lead (120 μg/animal) (GL), ginger (1%w/w) + lead (120 μg/animal) + fenitrothion (10 mg/kg) (GLF). Treatments were expanded for 28 days before pregnancy and during gestation period from zero to 6th day. Blood samples were taken at the day 20th of gestation and animals were sacrificed to investigate the effect of tested substances on dams and development of their fetuses. Inhibition in AchE in (F) and (LF) groups and elevation in plasma AchE in (L) groups were observed. Elevation in oxidative stress biomarker malondialdehyde (MDA) was recorded in all intoxicated groups concomitants with reduction in total reduced glutathione (GSH) and reduction in the activity of glutathione S-transferase (GST). Elevation in liver function biomarkers alanin amintransferase (ALT) and aspartate aminotransferase (AST) and reduction in plasma total protein and albumin were recorded in (F), (L) and (LF). Supplementation with ginger in diet attenuates the alteration in MDA, GSH, GST, ALT and AST, however, it failed to counteract the effect of F, L and LF on AchE, total protein and albumin. Significant alterations in maternal toxicity were recorded in (GF, GL, LF and GLF) compared with control group. Also, parameters of embryotoxicity and fetotoxicity indicated significant decrease in litter number that observed in F and L and the number of dead fetus/dam and litters number increased in L group. Supplementation with ginger decreased each of the number of died fetus, growth retardation and fetal length, while, it increased fetal weight. As regards to, teratological aspects, the percentage of skeletal malformations and visceral anomalies were observed in all feti obtained from treated groups with different percentages. Supplementation with ginger slightly attenuates the developmental toxicity of fenitrothion and/or lead. 相似文献
94.
Cassumunar ginger, Zingiber montanum (Koenig) Link ex Dietr. (Zingiberaceae), is called Phlai in Thailand. The current study investigates the levels of antioxidant activity and major volatile oil components in cassumunar ginger exposed to varying water deficits (0, 30, 60, 90 and 120 days before harvest) and light intensities (100%, 50% and 25% sunlight). A 120-day water deficit resulted in high volatile oil content and increased sabinene content, but DPPH scavenging activity was not affected. The quantity of volatile oil in the cassumunar ginger exposed to a 120-day water deficit was almost twice that of both the control and the sample exposed to a 30-day deficit. The highest terpinen-4-ol content was obtained after a 60-day water deficit, and (E)-1-(3′,4′-dimethoxyphenyl) butadiene content tended to decrease with prolonged water deficiency. The antioxidant activities of cassumunar ginger were 52.98%, 41.75% and 42.93% in plants grown at 100%, 50%, and 25% sunlight, respectively. Light intensity of 50% or 25% increased the biomass of cassumunar ginger but decreased the volatile oil content; antioxidant activity was not significantly affected. 相似文献
95.
施肥水平对生姜品质的影响 总被引:13,自引:1,他引:12
氮磷钾及其施用水平对生姜根茎品质的影响不同。适量追施氮肥(40kg/667m2)可显著提高蛋白质和氨基酸的含量;并有利于糖、淀粉、Vc和挥发油的形成,但氮肥用量过多,上述营养成分降低。增施磷肥对提高糖含量作用较大,在本试验范围内(0~15kg/667m2),可溶性糖含量随磷肥用量的增加而升高。增施钾肥对淀粉和纤维素的形成有较大促进作用。对Vc形成不利,钾肥用量越多,Vc含量越低,在本试验田肥力条件下,以每667m2追施N40kg、P2O57.5kg、K2O40kg效果最好,生姜品质最优。 相似文献
96.
97.
为了明确防治生姜甜菜夜蛾的杀虫剂的杀虫效果,在生姜主产区开展田间药效试验,调查了4种杀虫剂对生姜甜菜叶蛾的幼虫防治效果和叶片受害防治效果。结果表明:氯虫苯甲酰胺悬浮剂、虫螨腈悬浮剂和茚虫威悬浮剂对生姜甜菜夜蛾的防效较好,而甲氨基阿维菌素苯甲酸盐水分散粒剂防效较差;其中,667 m2施200 g/L氯虫苯甲酰胺悬浮剂有效成分用量2.0 g后14 d,虫防效为98.19%,叶片受害防效为86.13%;667 m2施240 g/L虫螨腈悬浮剂有效成分用量5.0 g后14 d,虫防效为80.29%,叶片受害防效为71.05%;667 m2施15%茚虫威悬浮剂有效成分用量5.0 g后14 d,虫防效为73.40%,叶片受害防效为65.39%。不同药剂对甜菜夜蛾的幼虫防效高于叶片受害防效,但同剂量处理条件下2种评价方法的防效趋势相一致。因此,氯虫苯甲酰胺悬浮剂、虫螨腈悬浮剂和茚虫威悬浮剂可作为生姜甜菜夜蛾防治药剂在生产中推广使用,同时在田间药效评价时,可采用叶片受害防效来替代幼虫防效的调查方法,从而避免幼虫假死性对调查结果的干扰。 相似文献
98.
以仔姜为研究对象,采用1-甲基环丙烯(1-MCP)熏蒸、二氧化氯和山梨酸钾溶液浸泡及复合处理(1-MCP+二氧化氯+山梨酸钾)对仔姜进行保鲜,定期测定仔姜硬度、腐烂率、色泽和失重率等感官指标,可溶性糖、总酚和VC含量等营养品质指标以及丙二醛含量、过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性和组织结构等指标,研究1-MCP、二氧化氯和山梨酸钾3种保鲜剂单独及复合处理对仔姜贮藏品质的影响。结果表明:3种保鲜剂单独及复合处理均可延缓仔姜腐烂率、硬度和失重率的下降,抑制仔姜可溶性糖、VC和总酚含量的下降,抑制过氧化物酶(POD)活性,其中,复合保鲜剂的保鲜效果最好,贮藏60 d时,仔姜仍能保持较好的生理状态和活性成分含量。研究结果可为仔姜采后保鲜技术提供理论参考。 相似文献
99.
为研究咪鲜胺及其代谢物在芹菜和生姜中的残留行为及膳食摄入风险,开展咪鲜胺及其代谢物在芹菜和生姜上的1年6地规范残留试验,气相色谱法(GC-ECD)分析样品,采用农药残留联席会议的方法评价咪鲜胺及其代谢物在芹菜和生姜中的膳食摄入风险。在咪鲜胺的添加水平为0.02、0.1、1 mg/kg时,咪鲜胺在姜上的平均回收率为77%~87%,相对标准偏差为3%~13%。在咪鲜胺添加水平为0.05、0.5、1、10 mg/kg时,咪鲜胺在芹菜上的平均回收率为75%~114%,相对标准偏差为3%~6%。咪鲜胺在芹菜中的半衰期为6.1~6.8 d。一般人群对咪鲜胺的国家估算每日摄入量(NEDI)为0.67331 mg,膳食摄入风险概率为106.9%。试验结果显示,咪鲜胺及其代谢物在中国普通人群的膳食摄入风险不在可接受范围内,本试验为咪鲜胺的合理使用、科学监管及制定咪鲜胺在芹菜和生姜上的最大残留限量(MRL)标准提供试验数据依据。 相似文献
100.