全文获取类型
收费全文 | 1621篇 |
免费 | 157篇 |
国内免费 | 35篇 |
专业分类
林业 | 136篇 |
农学 | 57篇 |
280篇 | |
综合类 | 177篇 |
农作物 | 96篇 |
水产渔业 | 99篇 |
畜牧兽医 | 746篇 |
园艺 | 27篇 |
植物保护 | 195篇 |
出版年
2023年 | 7篇 |
2022年 | 10篇 |
2021年 | 22篇 |
2020年 | 34篇 |
2019年 | 16篇 |
2018年 | 46篇 |
2017年 | 53篇 |
2016年 | 80篇 |
2015年 | 56篇 |
2014年 | 69篇 |
2013年 | 111篇 |
2012年 | 119篇 |
2011年 | 132篇 |
2010年 | 73篇 |
2009年 | 50篇 |
2008年 | 96篇 |
2007年 | 89篇 |
2006年 | 93篇 |
2005年 | 80篇 |
2004年 | 73篇 |
2003年 | 68篇 |
2002年 | 69篇 |
2001年 | 54篇 |
2000年 | 43篇 |
1999年 | 31篇 |
1998年 | 23篇 |
1997年 | 9篇 |
1996年 | 4篇 |
1995年 | 10篇 |
1994年 | 7篇 |
1993年 | 7篇 |
1992年 | 17篇 |
1991年 | 6篇 |
1990年 | 9篇 |
1989年 | 13篇 |
1988年 | 11篇 |
1987年 | 13篇 |
1986年 | 5篇 |
1985年 | 7篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1975年 | 4篇 |
1971年 | 3篇 |
1969年 | 9篇 |
1968年 | 4篇 |
1961年 | 6篇 |
1960年 | 4篇 |
1958年 | 5篇 |
1901年 | 3篇 |
1898年 | 3篇 |
排序方式: 共有1813条查询结果,搜索用时 187 毫秒
961.
Blanchart Anne Consalès Jean Noël Séré Geoffroy Schwartz Christophe 《Journal of Soils and Sediments》2019,19(8):3235-3244
Journal of Soils and Sediments - Given their increasing importance, soils should be considered as valuable resources by those involved in urban planning. Indeed, soils are expected to be... 相似文献
962.
G Vassiliadès 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1989,42(3):421-422
Observations made in Dakar abattoirs from March to December 1987 revealed that 46.39 per cent sheep and 57.89 per cent goats carried Oestrus ovis larvae. A clear relationship between cause and effect exists between nasal discharge and the presence of mature larvae. Because of their spine covering, they are irritating enough to provoke nasal mucosa inflammation with possible microbic complications. It is thus necessary to take into account the frequency and the pathogenicity of Oestrus ovis infection in the aetiologic study of respiratory affections of the small ruminants in Senegal. 相似文献
963.
The oral absorption and bioavailability of flumequine was studied in 1-, 5- and 18-week-old calves following intravenous and oral administration of different formulations of flumequine (Flumix, Flumix C and pure flumequine). Increasing age had a negative influence on the Cmax after the administration of Flumix, based on a larger VD in the older calves. The Cmax decreased from 5.02 +/- 1.46 micrograms/ml in the first week to 3.28 +/- 0.42 micrograms/ml in the 18th week. Adding colistin sulfate to the flumequine formulation and administring pure flumequine mixed with milk replacer had a negative effect on the Cmax of flumequine after oral administration of 5 and 10 mg/kg body weight. The bioavailability of the orally administered flumequine formulations was 100% in all cases except after the administration of Flumix C, for which it was 75.9 +/- 18.2%. The urinary recovery of flumequine after intravenous injection of a 10% solution varied from 35.2 +/- 2.3% for Group B, to 41.2 +/- 6.3% for Group C. The dosage of 5 mg/kg body weight Flumix twice daily in 1-week-old veal calves is sufficient to reach therapeutic plasma concentrations, based on a MIC value of 0.8 micrograms/ml of the target bacteria. In older calves it is advisable to increase the dosage 7.5 or 10 mg/kg body weight every 12 hours. In combination with colistin sulfate it is also advisable to increase the dosage slightly because of the negative effect of the colistin sulfate on the Cmax of flumequine. 相似文献
964.
Immunization and Parenteral Chemotherapy for the Control of Cattle Grubs Hypoderma Lineatum 总被引:1,自引:0,他引:1 下载免费PDF全文
Immunization with two types of warble larvae antigens A and B, the latter treated with tannic acid, and injections of dimethoate, an organic phosphate, were tried for the control of prehypodermic larvae of Hypoderma lineatum De Vill., and H. bovis L., in range calves.
In test groups of 20 calves, given intramuscularly, antigen A had no effect, but combined treatment with antigens A and B reduced the number of H. bovis L., larvae by 81 per cent (P<.001), and proved as effective as dimethoate subcutaneously or intramuscularly. H. lineatum De Vill., did not respond to any treatment.
Antigen B and dimethoate were free from harmful effects on the host, but antigen A caused anaphylaxis and irritation at the site of injection.
相似文献965.
966.
967.
Porter MB Long MT Getman LM Giguère S MacKay RJ Lester GD Alleman AR Wamsley HL Franklin RP Jacks S Buergelt CD Detrisac CJ 《Journal of the American Veterinary Medical Association》2003,222(9):1241-1247
OBJECTIVE: To determine signalment, clinical findings, results of diagnostic testing, outcome, and postmortem findings in horses with West Nile virus (WNV) encephalomyelitis. DESIGN: Retrospective study. ANIMALS: 46 horses with WNV encephalomyelitis. PROCEDURE: Clinical data were extracted from medical records of affected horses. RESULTS: On the basis of clinical signs and results of serologic testing, WNV encephalomyelitis was diagnosed in 46 of 56 horses with CNS signs. Significantly more males than females were affected. Increased rectal temperature, weakness or ataxia, and muscle fasciculations were the most common clinical signs. Paresis was more common than ataxia, although both could be asymmetrical and multifocal. Supportive treatment included anti-inflammatory medications, fluids, antimicrobials, and slinging of recumbent horses. Results of the IgM capture ELISA and the plaque reduction neutralization test provided a diagnosis in 43 horses, and only results of the plaque reduction neutralization test were positive in 3 horses. Mortality rate was 30%, and 71% of recumbent horses were euthanatized. One horse that had received 2 vaccinations for WNV developed the disease and was euthanatized. Follow-up communications with 19 owners revealed that most horses had residual deficits at 1 month after release from the hospital; abnormalities were resolved in all but 2 horses by 12 months after release. CONCLUSIONS AND CLINICAL RELEVANCE: Our findings were similar to those of previous WNV outbreaks in horses but provided additional clinical details from monitored hospitalized horses. Diagnostic testing is essential to diagnosis, treatment is supportive, and recovery rate of discharged ambulatory horses is < 100%. 相似文献
968.
De Clercq D van Loon G Nollet H Delesalle C Lefère L Deprez P 《The Veterinary record》2003,152(6):169-172
Between 1999 and 2001, seven horses with fever, dysphagia and a history of chronic upper respiratory tract infection lasting between three weeks and three months were examined. They had been treated unsuccessfully with a variety of antibiotics for three to four weeks. A deep abscess in a retropharyngeal lymph node was diagnosed in each case by clinical examination, endoscopy and echographic examination of the retropharyngeal region. The infected retropharyngeal lymph node of each horse was punctured with a spinal needle under ultrasound guidance. Pus was aspirated from four of the horses, and their abscesses were then rinsed with 0.9 per cent saline solution, and antibiotics (sodium ceftiofur or penicillin) were injected. In the other three horses the pus was too viscous to be aspirated, and the enlarged lymph node was opened along the tract of the needle and rinsed with chlorhexidine. All the horses were treated with penicillin for two weeks and in six of them the clinical signs gradually disappeared. The other horse continued to show fever and the penicillin treatment was continued for another 10 days, after which the signs gradually disappeared over a period of two months. 相似文献
969.
Phillips W Giguère S Franklin RP Hernandez J Adin D Peloso JG 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(4):597-599
Cardiac troponin I (cTnI), a myocardial polypeptide, is a highly sensitive and specific biomarker of myocardial injury in people and dogs. The structure of cTnI is highly conserved across species, and equine myocardium has high reactivity with human immunoassays. The purpose of this study was to describe cTnI concentrations in normal pastured and race-training Thoroughbred horses. Ten horses on pasture and 10 horses in race training were studied. Horses were considered normal on the basis of physical examination, training performance, electrocardiography (ECG), and echocardiography. Serum cTnI concentrations were determined with a colorimetric immunoassay. The assay has an analytical sensitivity of 0.04 ng/mL. Serum cTnI concentrations in race-training horses were not significantly different from those of pastured horses. When groups were combined, mean cTnI concentration (+/- SD) was 0.047 +/- 0.085 ng/mL. and the median was 0 (range, 0-0.35 ng/mL). The 90th percentile for both groups combined was 0.11 ng/mL. This study establishes a preliminary reference range for serum cTnI in normal Thoroughbred horses. 相似文献
970.