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321.
ObjectiveTo evaluate the effects of progressively increasing doses of acepromazine on cardiopulmonary variables and sedation in conscious dogs.Study designProspective, experimental study.AnimalsA group of six healthy, adult, mixed-breed dogs weighing 16.5 ± 5.0 kg (mean ± standard deviation).MethodsDogs were instrumented with thermodilution and arterial catheters for evaluation of hemodynamics and arterial blood gases. On a single occasion, acepromazine was administered intravenously to each dog at 10, 15, 25 and 50 μg kg–1 at 20 minute intervals, resulting in cumulative acepromazine doses of 10 μg kg–1 (ACP10), 25 μg kg–1 (ACP25), 50 μg kg–1 (ACP50) and 100 μg kg–1 (ACP100). Hemodynamic data and sedation scores were recorded before (baseline) and 20 minutes after each acepromazine dose.ResultsCompared with baseline, all acepromazine doses significantly decreased stroke index (SI), mean arterial pressure (MAP) and arterial oxygen content (CaO2) with maximum decreases of 16%, 17% and 21%, respectively. Cardiac index (CI) decreased by up to 19% but not significantly. Decreases of 26–38% were recorded for oxygen delivery index (DO2I), with significant differences for ACP50 and ACP100. Systemic vascular resistance index (SVRI) and heart rate did not change significantly. No significant difference was found among acepromazine doses for hemodynamic data. After ACP10, mild sedation was observed in five/six dogs and moderate sedation in one/six dogs, whereas after ACP25, ACP50 and ACP100, moderate sedation was observed in five/six or six/six dogs.Conclusions and clinical relevanceIn conscious dogs, acepromazine decreased MAP, SI, CaO2 and DO2I, but no significant dose effect was detected. SVRI was not significantly changed, suggesting that the reduction in MAP resulted from decreased CI. The ACP25, ACP50 and ACP100 doses resulted in moderate sedation in most dogs; ACP10 resulted in only mild sedation.  相似文献   
322.
N-硝基苯基脲类化合物的植物生长调节活性研究   总被引:2,自引:0,他引:2  
采用室内试验研究了6个N 硝基苯基脲化合物在质量浓度500mg·L-1下对水稻、油菜的生物活性.结果表明,它们对水稻成活、根长、根鲜重具有促进作用,对茎长、地上部鲜重具有抑制作用;该类化合物能促进油菜根长、地上部鲜重、根鲜重增加,而对其茎长具有抑制作用.同时,也讨论了各化合物的生物活性与其分子结构之间的相关性.  相似文献   
323.
芳香羧酸衍生物驱避剂活性测定及定量构效关系的研究   总被引:2,自引:0,他引:2  
 用家蝇作为实验昆虫,测定了40个芳香羧酸衍生物的驱避活性,并对其结果进行了定量构效关系的研究。结果显示,化合物B#-6、B#-8、M#-2、E#-6具有较高的驱避活性;沸点参数B是影响化合物驱避活性的主要因素。而化合物取代基的体积不应大于苯;取代基的亲脂性(logP)应在3.50左右。  相似文献   
324.
Diamide derivatives are biologically active molecules that have been widely applied in recent years in research on pesticides, especially insecticides.  Using a simple and environmentally friendly scheme, a series of new diamide derivatives containing a trifluoromethylpyridine skeleton was designed, synthesized, and confirmed by 1H, 19F and 13C NMR, and HR-MS.  Their insecticidal activities against Plutella xylostella and Helicoverpa armigera were measured and the relationship between structure and activity was investigated.  Eight of the title compounds (D2, D5, D10, D21, D28, D29, D30 and D33) showed 100% activity against Pxylostella at 500 mg L–1.  One compound, D33, still showed 100% activity against Pxylostella at 100 mg L–1 and had the lowest LC50 (lethal concentration 50%, 3.7 mg L–1) among the synthesized compounds.  Molecular docking analysis revealed that D33 could be thoroughly embedded in the active pocket of the ryanodine receptor via hydrogen bonding in a manner similar to the commercial insecticide chlorantraniliprole.  相似文献   
325.
偶氮苯衍生物的光致变色性及其应用   总被引:1,自引:3,他引:1  
综述了一些偶氮苯衍生物(ABD)的结构类型、变色特性、变色机理以及在光色材料科学领域如液晶聚合物、自组装单分子膜、非线性光学材料等方面的研究进展及存在的困难。  相似文献   
326.
目的:探讨pH值和结构修饰对盐酸小檗碱及其烷基化衍生物表观油水分配系数(P)的影响。方法:建立紫外分光光度法测定盐酸小檗碱及其烷基化衍生物含量的检测方法,并采用摇瓶法测定盐酸小檗碱及其烷基化衍生物在正辛醇-缓冲液体系中的表观油水分配系数。结果:pH值在2.0-8.0时,小檗碱lgP值均小于0,且其在水中的lgP值最小。小檗碱衍生物lgP值均大于0,但变化不大;随着修饰碳链的延伸,其油水分配系数逐渐增大,8-十六烷基小檗碱lgP值在不同pH值条件下均大于1,推测其在胃肠道的吸收优于小檗碱。结论:37℃下,pH值对盐酸小檗及其碱衍生物的表观油水分配系数影响不大,但与其结构改造中引入基团的极性呈正相关。  相似文献   
327.
尿液嘌呤衍生物法作为一种估测瘤胃微生物蛋白质合成量的新方法,克服了原有方法的缺点,简单易行,通过欧洲牛羊的实验证明该方法与其它方法的测定结果有很好的一致性,但此方法亦有其不足。由于尿中嘌呤衍生物排出量受动物品种的影响很大,不同品种间无通用性,所以现有的研究成果不能用于中国品种牛,更难以使该方法应用于生产。而国内在此方面的报道很有限,所以急需建立各品种反刍动物的估测模型,扩大该方法的应用范围。试验采用3头月龄(22±0.2),体重为(641±26.889)kg,体况相近的中国荷斯坦成年公牛,设计3×3的拉丁方,通过调整日粮精粗比来考察可消化有机物进食量对中国荷斯坦成年公牛尿嘌呤衍生物(PD)排出的影响。结果发现,试验牛尿中嘌呤衍生物中尿囊素大约为73% ̄88%,黄嘌呤和次黄嘌呤的含量很小,可以忽略不计,与以往对成年反刍动物的研究结果相似,与同个体犊牛期的研究结果相反。PD的排出量随可消化有机物(DOMI)和可消化粗蛋白(DCP)进食量升高而上升,存在较强的相关性(R2=0.88,n=9),其排出水平为414.09 ̄975.59mmol/d。肌酐酸的排出较稳定,各处理间差异不显著(P>0.05)。PDC与DOM和DCP进食量存在正相关,这与以往成年反刍动物的研究结果是相似的,与同个体犊牛期的研究结果相反,但相关性较弱。  相似文献   
328.
以亚甲二氧基苯为起始原料,经过溴化、硫化、环化等反应合成了19个未见文献报道的6,7-亚甲二氧基硫代苯并二氢吡喃-4-酮衍生物,其结构均经核磁共振氢谱和质谱确认。初步抑菌活性测试结果表明,在50 mg/L下,目标化合物对供试7种植物病原菌均有不同程度的抑制作用,其中化合物5b、5i、5k和5l对马铃薯干腐病菌 Fusarium solani的抑制率均达75%以上,5h和5i对番茄灰霉病菌Botrytis cinerea的抑制率分别是67.7%和70.4%。  相似文献   
329.
A series of water-soluble cationic chitosan derivatives were prepared by chemoselective functionalization at the amino group of five different parent chitosans having varying degrees of acetylation and molecular weight. The quaternary moieties were introduced at different alkyl spacer lengths from the polymer backbone (C-0, C-2 and C-6) with the aid of 3,6-di-O-tert-butyldimethylsilyl protection of the chitosan backbone, thus allowing full (100%) substitution of the free amino groups. All of the derivatives were characterized using 1H-NMR, 1H-1H COSY and FT-IR spectroscopy, while molecular weight was determined by GPC. Antibacterial activity was investigated against Gram positive S. aureus and Gram negative E. coli. The relationship between structure and activity/toxicity was defined, considering the effect of the cationic group’s structure and its distance from the polymer backbone, as well as the degree of acetylation within a molecular weight range of 7–23 kDa for the final compounds. The N,N,N-trimethyl chitosan with 100% quaternization showed the highest antibacterial activity with moderate cytotoxicity, while increasing the spacer length reduced the activity. Trimethylammoniumyl quaternary ammonium moieties contributed more to activity than 1-pyridiniumyl moieties. In general, no trend in the antibacterial activity of the compounds with increasing molecular weight or degree of acetylation up to 34% was observed.  相似文献   
330.
Summary A method has been developed for the rapid quantification of glucose, fructose and sucrose in potato tubers by capillary gas chromatography. Baseline separation of trimethylsilyl derivatives of β-D(−) fructose, α-D(+) glucose β-D(+) glucose, myoinositol (internal standard) and sucrose was achieved in under 10 min with a detection range of 10 ng to 3 μg per component. Use of an on-column injector resulted in the retention of a proportion of injected sucrose by the column, despite an oven starting temperature of 140°C. This did not occur with a splitless injection system (inlet temperature 220°C).  相似文献   
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