全文获取类型
收费全文 | 1623篇 |
免费 | 183篇 |
国内免费 | 119篇 |
专业分类
林业 | 491篇 |
农学 | 36篇 |
基础科学 | 12篇 |
151篇 | |
综合类 | 351篇 |
农作物 | 33篇 |
水产渔业 | 100篇 |
畜牧兽医 | 643篇 |
园艺 | 11篇 |
植物保护 | 97篇 |
出版年
2024年 | 10篇 |
2023年 | 26篇 |
2022年 | 28篇 |
2021年 | 37篇 |
2020年 | 41篇 |
2019年 | 64篇 |
2018年 | 31篇 |
2017年 | 33篇 |
2016年 | 52篇 |
2015年 | 71篇 |
2014年 | 132篇 |
2013年 | 66篇 |
2012年 | 94篇 |
2011年 | 90篇 |
2010年 | 111篇 |
2009年 | 130篇 |
2008年 | 96篇 |
2007年 | 102篇 |
2006年 | 112篇 |
2005年 | 128篇 |
2004年 | 87篇 |
2003年 | 68篇 |
2002年 | 23篇 |
2001年 | 25篇 |
2000年 | 18篇 |
1999年 | 17篇 |
1998年 | 18篇 |
1997年 | 9篇 |
1996年 | 5篇 |
1995年 | 8篇 |
1994年 | 8篇 |
1993年 | 15篇 |
1992年 | 12篇 |
1991年 | 12篇 |
1990年 | 17篇 |
1989年 | 10篇 |
1988年 | 7篇 |
1987年 | 5篇 |
1986年 | 6篇 |
1985年 | 15篇 |
1984年 | 6篇 |
1983年 | 19篇 |
1982年 | 3篇 |
1981年 | 13篇 |
1980年 | 12篇 |
1979年 | 25篇 |
1978年 | 6篇 |
1977年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有1925条查询结果,搜索用时 15 毫秒
11.
12.
《Journal of Veterinary Behavior: Clinical Applications and Research》2014,9(5):262-268
If the illicit tobacco trade were eliminated, governments could gain at least $31.3 billion a year, and more than 164,000 premature deaths a year could be avoided after 2030 (Joossens, Merriman, Ross, and Raw, 2009). Dogs have been used successfully in tobacco control programs, and there is a good chance that rats could also play an important role. In the present experiment, giant African pouched rats were trained to respond to filters that had been stored together with cigarettes (i.e., soaked) and to not respond to filters that had been soaked with noncigarette items. Generalization to untrained types of tobacco was then tested. The sensitivity of 4 rats trained on filters soaked with 1 of 7 types of cigarettes ranged from 86% to 100% (mean, 95%). There was very little evidence of generalization when the rats were tested on tobacco leaves and snuff but good evidence of generalization when the rats were tested on cigarettes that had been soaked with strong-smelling additives. These findings suggest that rats may be a valuable asset in the global effort to control illicit cigarette trade. 相似文献
13.
大豆抗原蛋白对幼龄动物致敏作用的研究进展 总被引:1,自引:0,他引:1
大豆抗原蛋白对幼龄动物的致敏作用及不易灭活性使其成为大豆及其制品在动物养殖中有效利用的主要瓶颈。本文从主要抗原蛋白的特性、致敏机制、对幼龄动物的影响、降低抗原蛋白的方法及有待进一步探索问题等方面进行了阐述,旨在为高效利用大豆及其制品,以及进一步深入研究提供参考。 相似文献
14.
15.
描述了毛竹的1个新栽培变种——绿槽龟甲竹。其竹秆下部一段的节交互歪斜,上下节在一侧相连,而节间在另一侧偏肿呈龟甲状,竹秆黄色,且龟甲状秆对称绿色纵条纹,分枝一侧纵沟槽绿色,叶片有淡黄色细纵条纹。 相似文献
16.
《Veterinary anaesthesia and analgesia》2021,48(6):922-929
ObjectiveTo analyse avian anaesthesia-related mortality in a UK zoological collection over a 5-year period and identify risk factors for mortality.Study designRetrospective cohort study.AnimalsA total of 135 individual birds across 37 species, anaesthetized during 206 events in a UK zoological collection between 1 January 2014 and 30 June 2019 (inclusive).MethodsAnaesthesia records were reviewed and variables such as age, body condition, weight, sex, duration of anaesthesia and health status were collated. Anaesthesia-related mortality was defined as those deaths occurring during anaesthesia and up to 7 days postanaesthesia. Outcome was analysed using multivariable conditional logistic regression. Overall mortality was defined and included birds euthanised during anaesthesia for non-anaesthesia related reasons. Data were summarised as median (range). A value of p < 0.05 was considered significant. Relative risks and 95% confidence intervals (95% CI) were calculated for the association between risk factors and anaesthetic death where a statistically significant difference was found.ResultsThe overall mortality rate was 10.19% (95% CI = 6.06–14.3%), while anaesthesia-related mortality was 3.88% (95% CI = 1.69–7.51%). Birds with an abnormal health status had a 15.53-fold (95% CI = 1.95–123.63) increased risk of death compared with those with a normal health status. The duration of anaesthesia was also a statistically significant risk factor (p = 0.021) in the univariable analysis, but not when combined with health status. No other variables were associated with anaesthesia-related mortality.Conclusions and clinical relevanceAbnormal health status and longer anaesthetic procedures were associated with a significantly increased risk of anaesthesia-related death in this population of birds. It is recommended that anaesthetic duration is minimized, and pre-existing diseases are diagnosed where possible prior to general anaesthesia of birds. Anaesthetizing healthy birds was associated with a low risk of mortality. 相似文献
17.
18.
19.
A. Lubojemska M. Borejko P. Czapiewski R. Dziadziuszko W. Biernat 《Veterinary and comparative oncology》2016,14(3):e70-e82
Olfactory neuroblastoma (ONB) is a rare tumour of nasal cavity and paranasal sinuses that arises from the olfactory neuroepithelium and has unpredictable clinical course. As the sense of smell is phylogenetically one of the first senses and olfactory neuroepithelium is evolutionary conserved with striking similarities among different species, we performed an extensive analysis of the literature in order to evaluate the similarities and differences between animals and humans on the clinical, morphological, immunohistochemical, ultrastructural and molecular level. Our analysis revealed that ONB was reported mainly in mammals and showed striking similarities to human ONB. These observations provide rationale for introduction of therapy modalities used in humans into the veterinary medicine. Animal models of neuroblastoma should be considered for the preclinical studies evaluating novel therapies for ONB. 相似文献
20.
Alterations due to dilution and anticoagulant effects in hematologic analysis of rodent blood samples on the Sysmex XT‐2000iV
下载免费PDF全文
![点击此处可从《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)