全文获取类型
收费全文 | 598篇 |
免费 | 28篇 |
专业分类
林业 | 92篇 |
农学 | 8篇 |
基础科学 | 1篇 |
130篇 | |
综合类 | 41篇 |
农作物 | 18篇 |
水产渔业 | 31篇 |
畜牧兽医 | 214篇 |
园艺 | 27篇 |
植物保护 | 64篇 |
出版年
2023年 | 8篇 |
2022年 | 4篇 |
2021年 | 3篇 |
2020年 | 12篇 |
2019年 | 14篇 |
2018年 | 14篇 |
2017年 | 4篇 |
2016年 | 13篇 |
2015年 | 5篇 |
2014年 | 15篇 |
2013年 | 31篇 |
2012年 | 41篇 |
2011年 | 53篇 |
2010年 | 25篇 |
2009年 | 24篇 |
2008年 | 40篇 |
2007年 | 30篇 |
2006年 | 35篇 |
2005年 | 36篇 |
2004年 | 31篇 |
2003年 | 31篇 |
2002年 | 19篇 |
2001年 | 7篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 6篇 |
1997年 | 4篇 |
1995年 | 4篇 |
1992年 | 4篇 |
1988年 | 4篇 |
1986年 | 2篇 |
1984年 | 4篇 |
1978年 | 3篇 |
1976年 | 3篇 |
1968年 | 3篇 |
1967年 | 2篇 |
1966年 | 3篇 |
1965年 | 2篇 |
1964年 | 2篇 |
1963年 | 2篇 |
1962年 | 2篇 |
1959年 | 2篇 |
1954年 | 3篇 |
1941年 | 4篇 |
1937年 | 12篇 |
1935年 | 9篇 |
1934年 | 5篇 |
1933年 | 8篇 |
1927年 | 2篇 |
1916年 | 2篇 |
排序方式: 共有626条查询结果,搜索用时 15 毫秒
111.
Grayson A. Doss Dustin M. Fink Kurt K. Sladky Christoph Mans 《Veterinary anaesthesia and analgesia》2017,44(5):1175-1183
Objective
To compare dexmedetomidine–midazolam with alfaxalone–midazolam for sedation in leopard geckos (Eublepharis macularius).Study design
Prospective, randomized, blinded, complete crossover study.Animals
Nine healthy adult leopard geckos.Methods
Geckos were administered a combination of dexmedetomidine (0.1 mg kg?1) and midazolam (1.0 mg kg?1; treatment D–M) or alfaxalone (15 mg kg?1) and midazolam (1.0 mg kg?1; treatment A–M) subcutaneously craniodorsal to a thoracic limb. Heart rate (HR), respiratory rate (fR), righting reflex, palpebral reflex, superficial and deep pain reflexes, jaw tone and escape response were assessed every 5 minutes until reversal. Conditions for intubation and response to needle prick were evaluated. Antagonist drugs [flumazenil (0.05 mg kg?1) ± atipamezole (1.0 mg kg?1)] were administered subcutaneously, craniodorsal to the contralateral thoracic limb, 45 minutes after initial injection, and animals were monitored until recovery.Results
HR, but not fR, decreased significantly over time in both treatments. HR was significantly lower than baseline at all time points in D–M and for all but the 5 and 10 minute time points in A–M. HR was significantly higher in A–M at all time points after drug administration when compared with D–M. Sedation scores between protocols were similar for most time points. All animals in A–M lost righting reflex compared with seven out of nine (78%) geckos in D–M. Geckos in A–M lost righting reflex for significantly longer time. Mean ± standard deviation time to recovery after antagonist administration was 6.1 ± 2.2 minutes for D–M and 56 ± 29 minutes for A–M, and these times were significantly different.Conclusions and clinical relevance
Combination D–M or A–M provided sedation of a level expected to allow physical examinations and venipuncture in leopard geckos. A–M provided a faster onset of sedation compared with D–M. Recovery was significantly faster following antagonist reversal of D–M, compared with A–M. 相似文献112.
Effect of supplementation of Simada sheep with graded levels of concentrate meal on feed intake,digestibility and body-weight parameters 总被引:1,自引:1,他引:0
Jemberu Dessie Solomon Melaku Firew Tegegne Kurt J. Peters 《Tropical animal health and production》2010,42(5):841-848
The experiment consisting of 7 days of digestibility and 90 days of feeding trial was conducted at Wogda (Ethiopia) to determine
the effect of supplementation of graded levels of concentrate mix (CM) on feed intake, digestibility, and body weight (BW)
change in hay-based feeding of Simada sheep. Twenty-yearling Simada sheep with a mean initial BW of 17.9 ± 0.81 kg (mean ±
SD) were used in randomized complete block design arranged into five blocks of four animals. The four dietary treatments that
consisted of hay alone (T1), hay +150 g dry matter (DM; T2, low), hay +250 g DM (T3, medium), and hay +350 g DM (T4, high)
CM were randomly assigned to each sheep within a block. The CM consisted of wheat bran (WB), noug seed (Guizotia abyssinica) meal and safflower (Carthamus tinctorius) seed meal at the ratio of (2:1:1), respectively. Supplementation with T2 and T3 increased (P < 0.001) total DM and organic matter intake than the control treatment. Overall, supplementation improved (P < 0.001) crude protein intake, digestibility, feed conversion efficiency, BW gain, and profitability compared to the control,
whereas sheep on the high than the low and medium level of supplementation performed better in these parameters among the
supplemented treatments. From the results of this study, T4 is recommended as the best level of supplementation since it resulted
in better nutrient utilization, animal performance, and profitability. 相似文献
113.
在低水平豆粕型母猪哺乳期饲料中添加合成赖氨酸以平衡日粮的营养水平,不会对母猪当前和以后的生产性能产生负面影响,虽然合成氨基酸的成本增加了,但整体生产成本能够下降。 相似文献
114.
115.
116.
Röhrig E Hamel D Pfister K 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(9-10):411-418
The detection and therapy of canine vector-borne diseases in imported dogs are of major importance in small animal practice. Over the last years, the import of dogs from the Mediterranean region and Southeast Europe has increased, countries often endemic for a variety of vector-borne diseases such as babesiosis, hepatozoonosis, leishmaniosis, dirofilariosis or ehrlichiosis. This retrospective study presents the evaluation of data from our diagnostic laboratory on vector-borne infections in imported dogs from the years 2004-2008. Specific antibodies were detectable in 20.5% of all samples with individual detection rates of 8.9%, 9.6% and 10.8% for Babesia canis ssp., Leishmania spp. and/or Ehrlichia canis. A total of 5.5% of all samples tested by direct methods were positive. Up to 1.1% of Giemsa-stained blood/buffy coat smears were positive for B. canis ssp., Rickettsia spp. or Hepatozoon spp. Microfilariae were detectable by the Knott's Test in 6.4% and heartworm antigen was detectable using the DiroChek-ELISA in 3% of the examined samples. EDTA-blood samples were positive for Leishmania spp.-(14.9%), E. canis- (5.3%) and A. phagocytophilum-DNA (5.0%) by PCR. Therewith, imported dogs have a high chance of being carriers of pathogens. As some diseases may also be of a zoonotic concern, in case of the availability of competent vectors, the key focus in the future should be aimed at the prevention of importing infected dogs or at compulsory diagnostic screening and treatment of infected dogs at the time of import. 相似文献
117.
Vermeire S Audenaert K De Meester R Vandermeulen E Waelbers T De Spiegeleer B Eersels J Dobbeleir A Peremans K 《Research in veterinary science》2011,91(3):465-472
The serotonergic system is disturbed in different mood and affective disorders, with especially the serotonin (5-HT) 2A receptor involved in impulsive aggressiveness and anxiety. The aim of the study was to evaluate the involvement of the brain 5-HT 2A receptor in dogs with different behavioural disorders. Three groups of drug naive dogs were studied: 22 dogs showing impulsive aggressive behaviour, 22 showing normal behaviour, and 22 showing anxious behaviour. The serotonin 2A receptor was evaluated with Single Photon Emission Computed Tomography (SPECT) and the serotonin 2A receptor-selective radiopharmaceutical (123)I-R91150. A serotonin 2A receptor binding index (BI), proportional to the cortical receptor density, was calculated. A receiver operating characteristic (ROC) analysis was performed to determine cut-off values at which optimal sensitivity and specificity are achieved and to evaluate the general performance of the BI in reflecting the state of the dog, i.e., impulsive aggressive, normal or anxious. Significantly (P<0.0056) altered 5-HT 2A receptor binding indices were found in bilateral frontal, temporal and occipital cortical brain areas of the dogs behaving abnormally, with consistently increased BI in impulsive aggressive dogs and decreased BI in anxious dogs. These results provide clear evidence for a disturbed serotonergic balance in canine impulsive aggression and anxiety disorders. A right frontal cut-off value of ≥1.92 with 86.4% sensitivity and 2.3% (1-specificity) was obtained for the impulsive aggressive dogs. Differentiating the anxious dogs from the rest of the population was possible with a cut-off value of ≤1.73 with 86.4% sensitivity and 18.2% (1-specificity). We conclude that SPECT imaging with the radioligand (123)I-R91150 can be a helpful tool in evaluating the involvement of the serotonin 2A receptor in the complex mechanisms of impulsive aggressive and anxious behaviour. The 5HT-2A binding index of the right frontal cortex appears to be a valid biomarker in differentiating the studied canine behavioural disorders. 相似文献
118.
119.
120.
Carol Reinero Lance C. Visser Heidi B. Kellihan Isabelle Masseau Elizabeth Rozanski Cécile Clercx Kurt Williams Jonathan Abbott Michele Borgarelli Brian A. Scansen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(2):549-573
Pulmonary hypertension (PH), defined by increased pressure within the pulmonary vasculature, is a hemodynamic and pathophysiologic state present in a wide variety of cardiovascular, respiratory, and systemic diseases. The purpose of this consensus statement is to provide a multidisciplinary approach to guidelines for the diagnosis, classification, treatment, and monitoring of PH in dogs. Comprehensive evaluation including consideration of signalment, clinical signs, echocardiographic parameters, and results of other diagnostic tests supports the diagnosis of PH and allows identification of associated underlying conditions. Dogs with PH can be classified into the following 6 groups: group 1, pulmonary arterial hypertension; group 2, left heart disease; group 3, respiratory disease/hypoxia; group 4, pulmonary emboli/pulmonary thrombi/pulmonary thromboemboli; group 5, parasitic disease (Dirofilaria and Angiostrongylus); and group 6, disorders that are multifactorial or with unclear mechanisms. The approach to treatment of PH focuses on strategies to decrease the risk of progression, complications, or both, recommendations to target underlying diseases or factors contributing to PH, and PH-specific treatments. Dogs with PH should be monitored for improvement, static condition, or progression, and any identified underlying disorder should be addressed and monitored simultaneously. 相似文献