全文获取类型
收费全文 | 442篇 |
免费 | 37篇 |
专业分类
林业 | 26篇 |
农学 | 9篇 |
115篇 | |
综合类 | 24篇 |
农作物 | 32篇 |
水产渔业 | 36篇 |
畜牧兽医 | 190篇 |
园艺 | 11篇 |
植物保护 | 36篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 5篇 |
2021年 | 12篇 |
2020年 | 14篇 |
2019年 | 11篇 |
2018年 | 16篇 |
2017年 | 13篇 |
2016年 | 21篇 |
2015年 | 9篇 |
2014年 | 13篇 |
2013年 | 16篇 |
2012年 | 26篇 |
2011年 | 33篇 |
2010年 | 27篇 |
2009年 | 23篇 |
2008年 | 36篇 |
2007年 | 26篇 |
2006年 | 29篇 |
2005年 | 23篇 |
2004年 | 27篇 |
2003年 | 26篇 |
2002年 | 17篇 |
2001年 | 4篇 |
2000年 | 9篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 6篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1979年 | 1篇 |
1975年 | 1篇 |
1961年 | 1篇 |
排序方式: 共有479条查询结果,搜索用时 265 毫秒
101.
102.
Aartsma Yavanna Hao Yueyi Dicke Marcel van der Werf Wopke Poelman Erik H. Bianchi Felix J. J. A. 《Landscape Ecology》2020,35(4):907-919
Landscape Ecology - Tritrophic interactions may be affected by local factors and the broader landscape context. At small spatial scales, carnivorous enemies of herbivorous insects use... 相似文献
103.
Bravo Carlo Millo Christian Covelli Stefano Contin Marco De Nobili Maria 《Journal of Soils and Sediments》2020,20(2):1074-1086
Journal of Soils and Sediments - Humic acids (HA) have several environmental roles, but are particularly important in aquatic environments, being recognized as redox active natural organic matter... 相似文献
104.
Alessia Diana DVM PHD Marco Pietra DVM Carlo Guglielmini DVM Andrea Boari DVM Giuliano Bettini DVM Mario Cipone DVM 《Veterinary radiology & ultrasound》2003,44(5):566-569
The ultrasonographic findings for four cats with intestinal smooth muscle hypertrophy are described. In two cats, intestinal smooth muscle hypertrophy was associated with chronic enteritis. In the remaining two cats, intestinal smooth muscle hypertrophy affected the intestinal tract proximal to stenosis due to alimentary lymphoma and an intestinal foreign body, respectively. Moderate increased thickness of the affected intestinal wall, measuring 7-8 mm, was evident on abdominal ultrasonographic examination of all subjects. In addition, the ultrasonographic five-layered feature of the intestinal wall was maintained, and only the muscular layer appeared thickened. Abdominal ultrasound allowed a presumptive diagnosis of intestinal smooth muscle hypertrophy that was confirmed histologically in all cats. 相似文献
105.
B A Bokhout P J van der Heijden M J Nabuurs A T Bianchi 《Comparative immunology, microbiology and infectious diseases》1986,9(2-3):277-283
A stable water-in-oil emulsion was injected intraperitoneally (i.p.) in piglets about 5 days before weaning to prevent post-weaning diarrhoea (PWD) and oedema disease (OD). So far more than 200,000 piglets have been treated with this adjuvant on a number of farms. On these farms the mortality rate due to PWD and OD decreased, whereas the need for antibiotic treatment declined. Experiments involving alternate application of adjuvant and physiological saline, or adjuvant treatment and no treatment at all, showed a statistically significant positive effect of adjuvant application. The effect of i.p. adjuvant application on specific and non-specific defence mechanisms were examined in well defined rat- and mouse-models, to throw light upon the mechanisms behind the observed adjuvant effect in piglets. 相似文献
106.
Hormonal changes and follicular activity after treatment with intravaginal progesterone‐releasing devices in llamas
下载免费PDF全文
![点击此处可从《Reproduction in domestic animals》网站下载免费的PDF全文](/ch/ext_images/free.gif)
MV Cavilla CP Bianchi F Aguilera M Hermida MA Aba 《Reproduction in domestic animals》2016,51(6):930-939
Plasma progesterone (P4) concentrations and follicular activity after administration of different P4 doses were evaluated in 33 adult female llamas treated with intravaginal devices. In Study 1, a group of llamas (n = 10) was treated with an intravaginal device (IVD) containing 160 (n = 5) or 780 mg of P4 (n = 5). Based on the results from the first study, in Study 2, females with follicles at different stages of development were treated with the IVD containing 780 mg of P4 (n = 21) or remain untreated (control; n = 12) to evaluate the effect of P4 on follicular activity. In Study 1, the IVD containing 160 mg of P4 induced follicular turnover in 60% of females while the remaining 40% of llamas developed persistent follicles. Thus, this device controlled follicular activity in llamas, although it promotes the persistence of follicles present at start of treatment. Conversely, in both studies, the IVD containing 780 mg of P4 suppressed follicular development and hasten the emergence of a new follicular wave in all females regardless of the follicular phase at insertion. Additionally, in Study 2, this device effectively concentrated the appearance of follicles with ovulatory diameter at a definite time after treatment in comparison with control animals. In conclusion, treatment with an IVD containing 780 mg of P4 would be considered for the control of follicular activity in llamas as it ensures the presence of a young follicle with ovulatory diameter by day 6 after the end of treatment in all females. 相似文献
107.
108.
Pharmacokinetic study of enrofloxacin in Nile tilapia (Oreochromis niloticus) after a single oral administration in medicated feed
下载免费PDF全文
![点击此处可从《Journal of veterinary pharmacology and therapeutics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
J. A. Teles L. C. Castello Branco M. Del Bianchi F. Pilarski F. G. R. Reyes 《Journal of veterinary pharmacology and therapeutics》2016,39(2):205-208
The objective of this study was to evaluate the disposition kinetics of enrofloxacin (ENR) in the plasma and its distribution in the muscle tissue of Nile tilapia (Oreochromis niloticus) after a single oral dose of 10 mg/kg body weight via medicated feed. The fish were kept at a temperature between 28 and 30 °C. The collection period was between 30 min and 120 h after administration of the drug. The samples were analyzed by high‐performance liquid chromatography with a fluorescence detector (HPLC‐FLD). The ENR was slowly absorbed and eliminated from the plasma (Cmax = 1.24 ± 0.37 μg/mL; Tmax = 8 h; T1/2Ke = 19.36 h). ENR was efficiently distributed in the muscle tissue and reached maximum values (2.17 ± 0.74 μg/g) after 8 h. Its metabolite, ciprofloxacin (CIP), was detected and quantified in the plasma (0.004 ± 0.005 μg/mL) and muscle (0.01 ± 0.011 μg/g) for up to 48 h. After oral administration, the mean concentration of ENR in the plasma was well above the minimum inhibitory concentrations (MIC50) for most bacteria already isolated from fish except for Streptococcus spp. This way the dose used in this study allowed for concentrations in the blood to treat the diseases of tilapia. 相似文献
109.
110.