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31.
该文总结了安徽省域耕地等别分布现状、与上轮成果对比分析,分析了规律与原因,进而提出了定期更新耕地质量分等成果、完善耕地质量监管机制等方面的耕地质量建设对策,以期未来的耕地质量建设与管理更利于"双保"战略的落实。 相似文献
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以玉米膜下滴灌栽培技术研究成果为依据,总结了辽宁省阜新蒙古族自治县东部地区推广应用该成果的具体措施,并提出相应对策。 相似文献
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Anthracnose of cashew (Anacardium occidentale) was studies on various genotypes and locations in Mozambique. Colletotrichum gloeosporioides was identified as the anthracnose causal agent using polymerase chain reaction. The relationships between incidence and severity of anthracnose on cashew genotypes were statistically analyzed by regression. Anthracnose leaf incidence, which is practically easy to evaluate, was consistently associated with leaf severity, and their relationships can be estimated using the restricted exponential function across locations, crop seasons, genotype and fungicide trials. Pooled data enabled estimation of initial incidence of 1.43% with percentage variance accounting for 83.2 and standard error of 8.3. By computing incidence data into the summary equation, 24 changes of 0, 1, 5, 10 and 40%, resulted in changes of severity estimates of 0.01, 0.05, 0.10, 0.50 and 1.00%, respectively. The maximum disease incidence was estimated as 80% when the severity reached only 5%. Increase in severity was observed afterward, approached a maximum of 25% when leaf detachment is observed. The use of incidence data for epidemic comparisons, genotype and fungicide evaluation in cashew orchards is recommended. Anthracnose incidence on leaves however, could not predict incidence on nuts. 相似文献
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对28个樱桃番茄品种的田间抗病性、植株类型、单果质量、果色、可溶性固形物含量等主要经济性状进行调查。试验结果表明,感病品种红艳发病最重,发病率为73.67%,其次是红箭、红日和金艳,发病率分别为23.33%、21.67%和20.33%,其他品种发病率都在20%以下;28个品种的果实颜色、大小、口感等差异明显,除黑宝石映泰及黄金蛋可溶性固形物含量在4.10%以下外,其他品种可溶性固形物含量都达5.20%以上。综合分析,筛选出绿天使、粉仙、红娘9号、绿圆、格丽贝、红椭圆等11个抗青枯病且经济性状优良的樱桃番茄品种,为优质抗青枯病樱桃番茄的选育和推广提供了参考。 相似文献
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Adin DB Diley-Poston L 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):737-741
BACKGROUND: Papillary muscle hypertrophy can occur in conjunction with, or as the only indication of, hypertrophic cardiomyopathy or other diseases that result in left ventricular concentric hypertrophy (LVCH). Assessment of papillary muscle size is usually subjective because objective measures have not been reported. HYPOTHESIS: The study hypothesis was that papillary muscle dimensions are different between normal cats and cats with LVCH. ANIMALS: Echocardiograms from 44 normal cats and 40 cats with LVCH were included in the study. METHODS: All measurements were taken from the right parasternal short-axis view at the level of the papillary muscles at end-diastole. Three methods were used to assess papillary muscle size: the area subtraction method, the direct area trace method, and the diameter method. Measurements were compared between cat groups and method comparisons were made among methods for area determination. RESULTS: Cats with LVCH were older and had significantly greater left ventricular septal and free wall thicknesses and larger left atrial measurements than normal cats (P < .0006). Papillary muscle measurements were significantly greater by all measurement methods in cats with LVCH than in cats with normal echocardiograms (P < .0001). The area subtraction method and direct area trace method showed moderate agreement. CONCLUSIONS AND CLINICAL IMPORTANCE: Papillary muscle measurements were larger for LVCH cats than normal cats; however, some overlap was present. The establishment of these objective measures adds to the echocardiographic examination of cats. 相似文献
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A dynamic optimization model was developed and used to evaluate alternative foot-and-mouth disease (FMD) control strategies. The model chose daily control strategies of depopulation and vaccination that minimized total regional cost for the entire epidemic duration, given disease dynamics and resource constraints. The disease dynamics and the impacts of control strategies on these dynamics were characterized in a set of difference equations; effects of movement restrictions on the disease dynamics were also considered. The model was applied to a three-county region in the Central Valley of California; the epidemic relationships were parameterized and validated using the information obtained from an FMD simulation model developed for the same region. The optimization model enables more efficient searches for desirable control strategies by considering all strategies simultaneously, providing the simulation model with optimization results to direct it in generating detailed predictions of potential FMD outbreaks. 相似文献
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