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41.
应用紫外光谱法研究了3种氨基甲酸酯类农药对DNA的损伤作用,结果显示,这3种氨基甲酸酯类农药能够引起ctDNA的紫外吸收光谱发生发射波长以及吸收强度的变化,从而说明3种氨基甲酸酯农药能够与ctDNA进行作用,即意味着3种氨基甲酸酯类农药进入生物有机体后有可能通过形成DNA加合物的形式而进一步导致基因突变,最终对生物体的DNA产生化学损伤。  相似文献   
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改进了气相色谱—质谱(GC-MS)测定葡萄酒中氨基甲酸乙酯(EC)的方法,检测和分析了不同年份葡萄酒中的EC含量。葡萄酒样品加入EC-d5内标,经硅藻土吸附、二氯甲烷洗脱、减压浓缩、氮气吹干和甲醇复溶,气相色谱—质谱选择离子检测。方法检出限和定量限分别不大于2ng/mL和5ng/mL,验证的浓度范围内(5~100ng/mL),保持良好线性,r2=0.999 8,回收率为89.9%~100.1%,相对标准偏差为2.91%~4.76%。对4个品种、3个年份的葡萄酒中EC的评价结果表明,年份越早葡萄酒中EC含量越高;贮藏时间是导致葡萄酒中EC含量升高的主要因素。  相似文献   
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Xie H  Yan MC  Jin D  Liu JJ  Yu M  Dong D  Cai CC  Pan SL 《Fitoterapia》2011,82(7):1086-1092
Piper laetispicum C.DC. (Piperaceae), is an endemic climbing, glabrous plant distributed in the southern part of China. A novel alkaloid amide, Laetispicine, from it has been proven to possess antidepressant activity. In this present study, antidepressant and antinociceptive effects of the ethyl acetate extract (EAE) of P. laetispicum have been studied in forced swimming, open field, acetic acid writhing and formalin tests in KM mice. A significantly antidepressant-like effect was showing at doses of higher than 60 mg/kg, which was not due to an increase in locomotive activity. The EAE also presented an analgesic effect, in our studies. At lower doses (30 mg/kg) the antinociceptive effect was likely mediated via peripheral inflammation and changes in central processing, and at higher doses (120 mg/kg) that was due to both central and peripheral pathways. We also quantitatively analyzed the major components of EAE by HPLC and approached the structure–activity relationship between structure of amide alkaloids and its antidepressant activities. The antidepressant effective components of EAE might be Leatispiamide A and Laetispicine. In their molecular structures, the isolated double bond from benzene ring and conjugated double bond located at 2–3 and 4–5 were necessary for its antidepressant activity.  相似文献   
45.
Previously, we reported that rhizome powder of Kaempferia parviflora Wall. Ex. Baker prevented obesity and a range of metabolic diseases. In this study, to clarify which molecular mechanisms and active ingredients of K. parviflora have an anti-obesity effect, we investigated the effect of ethyl acetate extract of K. parviflora (KPE) on TSOD mice, a spontaneously obese Type II diabetes model, and on pancreatic lipase. In the TSOD groups, KPE showed a suppressive effect on body weight increase and visceral fat accumulation and also showed preventive effects on symptoms related to insulin resistance, hypertension and fatty liver. In addition, KPE also suppressed body weight increase and food intake in TSNO mice groups, which served as reference animals, at an early stage of administration. Searching for the ingredients in KPE revealed that KPE contains at least 12 kinds of polymethoxyflavonoid (PMF). Furthermore, KPE and its component PMFs showed an inhibitory effect on pancreatic lipase. The above results suggest that KPE has a preventive effect on obesity and various metabolic diseases. The mechanisms of action probably involve inhibition of pancreatic lipase by the PMFs in KPE.  相似文献   
46.
尹晓明  李学林 《土壤》2020,52(5):901-910
氨基甲酸酯类农药是一类高效广谱型杀虫剂,近年来在农业生产中被广泛使用,然而由此带来的环境污染和食品健康问题也日益引起关注。无论是样品的前处理方法还是仪器检测方法都有待不断地完善和发展,因此,开发理想的样品前处理方法和更加有效的仪器分析方法成为该领域的研究热点。本文在查阅了近年国内外相关文献61篇的基础上,就环境样品氨基甲酸酯类农药的分离提取方法以及不同方法的优缺点做分析,同时对氨基甲酸酯类农药的仪器分析方法及其发展趋势做总结,以期为研究环境样品氨基甲酸酯类农药的分析技术提供有益的参考。  相似文献   
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Objective – To describe the common clinical signs, laboratory abnormalities, treatment, and prognosis associated with acute aldicarb toxicosis in dogs. Design – Retrospective observational study from 2001 to 2009. Setting – Urban referral hospital. Animals – Fifteen client‐owned dogs. Interventions – None. Measurements and Main Results – The most common clinical signs associated with acute aldicarb toxicosis were vomiting, ptyalism, diarrhea, and tremors. Of the 15 dogs, 11 were admitted to the hospital for treatment, 2 were euthanized at presentation and 2 were discharged against medical advice following minimal treatment and lost to follow‐up. Laboratory abnormalities included lactic acidosis and hyperglycemia in 12 and 9 patients, respectively. Treatment of hospitalized dogs included induction of emesis with apomorphine (4 dogs), activated charcoal (5), IV fluids (11), atropine (7), methocarbamol (3), diazepam (1), pralidoxime (1) and diphenhydramine (1). Ten of 11 hospitalized dogs survived to discharge; 1 was euthanized following a respiratory arrest after 36 hours of hospitalization. One patient received mechanical ventilation and treatment for pneumonia before discharge from the hospital. The median duration of hospitalization was 22 hours (range 12–168 h). Conclusions – Acute aldicarb toxicosis carries a good prognosis for survival and hospital discharge with treatment. Supportive care should be considered for at least 18–24 hours to monitor for response to therapy and development of respiratory failure.  相似文献   
48.
合成了碳酸酯类化合物23个和苯氨基甲酸苯酯类化合物7个。杀螺初筛试验发现,8个碳酸酯化合物具有杀螺活性,其中,化合物I1和I11,10ppm的杀螺率为100%和96.7%。碳酸苯酯的苯环上,用硝基或3个以上的氯原子取代,有利于增强该类化合物的杀螺作用。杀螺效果较好的三氯苯碳酸酯改变成同电异素体类似物,苯氨基甲酸酯后,杀螺作用明显下降。  相似文献   
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甘蓝型油菜EMS突变体库构建及抗除草剂突变体筛选   总被引:3,自引:0,他引:3  
为了利用诱变技术快速创造变异类型丰富的油菜新材料用于油菜遗传改良,分别用0.4%、0.8%、1.0%和1.2%的EMS(甲基磺酸乙酯)溶液对甘蓝型油菜中双9号种子进行诱变处理。结果发现:(1)1.0%的EMS溶液是处理中双9号干种子的最适浓度,4种不同浓度处理M2代表型变异率依次为11.26%、14.82%、27.19%和12.38%;(2)EMS诱变具有器官特异性;(3)M2代突变体库中筛选到3株苯磺隆抗性突变体,突变率约为10-4。现已创建了包括子叶、叶片、花器、株型、角果等多器官变异类型的突变体库,为油菜遗传研究提供了丰富的种质资源。   相似文献   
50.
Weedy rice (Oryza sativa) is a close relative of domesticated rice and a noxious weed prevalent in rice fields in world regions where rice is grown. Weedy rice management has remained challenging to farmers, mainly due to the weed's physiological and morphological resemblance to rice cultivars. The introduction of Clearfield® rice provides an alternative solution and an additional tool for integrated weed management. Clearfield® rice-based programs result in the cleanest rice fields in the southern U.S. However, persistent application of the imidazolinone herbicides (imazethapyr, imazamox, and imazapic) in Clearfield® rice raises concerns about the possible evolution of resistance to ALS-inhibitor herbicides in weedy rice and the transfer of resistance trait. The risk of resistant weedy rice evolution is much higher in Asia, Latin America, and other tropical regions where there is no winterkill and rice is planted at least twice each year. Herbicide carryover to rotational crops is also a concern. We summarized the progress of commercialization of Clearfield® rice in 15 countries across the continents of America, Asia and Europe. In some countries, imidazolinone-resistant weedy rice outcrosses have been found abundant, thereby negating the utility of Clearfield® technology. The persistence of imidazolinone herbicide residues in the soil is a concern in regions where multiple crops are planted in a year, or the following year. These challenges should be anticipated by countries that are considering adopting Clearfield® rice technology. Issues associated with gene escape, resistance evolution in weedy rice, and herbicide carryover to rotational crops remain to be resolved. Research to achieve sustainable solutions for weedy rice management, must be continued and intense educational programs for growers must be sustained.  相似文献   
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