全文获取类型
| 收费全文 | 8101篇 |
| 免费 | 3577篇 |
| 国内免费 | 2篇 |
专业分类
| 林业 | 321篇 |
| 农学 | 469篇 |
| 基础科学 | 13篇 |
| 1633篇 | |
| 综合类 | 339篇 |
| 农作物 | 141篇 |
| 水产渔业 | 2621篇 |
| 畜牧兽医 | 4690篇 |
| 园艺 | 67篇 |
| 植物保护 | 1386篇 |
出版年
| 2024年 | 3篇 |
| 2023年 | 17篇 |
| 2022年 | 28篇 |
| 2021年 | 175篇 |
| 2020年 | 511篇 |
| 2019年 | 1084篇 |
| 2018年 | 951篇 |
| 2017年 | 985篇 |
| 2016年 | 982篇 |
| 2015年 | 850篇 |
| 2014年 | 849篇 |
| 2013年 | 1031篇 |
| 2012年 | 594篇 |
| 2011年 | 634篇 |
| 2010年 | 672篇 |
| 2009年 | 301篇 |
| 2008年 | 358篇 |
| 2007年 | 178篇 |
| 2006年 | 246篇 |
| 2005年 | 205篇 |
| 2004年 | 197篇 |
| 2003年 | 201篇 |
| 2002年 | 194篇 |
| 2001年 | 78篇 |
| 2000年 | 115篇 |
| 1999年 | 21篇 |
| 1998年 | 16篇 |
| 1997年 | 25篇 |
| 1996年 | 8篇 |
| 1995年 | 20篇 |
| 1994年 | 14篇 |
| 1993年 | 14篇 |
| 1992年 | 6篇 |
| 1991年 | 5篇 |
| 1990年 | 8篇 |
| 1989年 | 4篇 |
| 1987年 | 5篇 |
| 1986年 | 4篇 |
| 1985年 | 4篇 |
| 1984年 | 6篇 |
| 1983年 | 4篇 |
| 1982年 | 4篇 |
| 1980年 | 6篇 |
| 1979年 | 6篇 |
| 1978年 | 10篇 |
| 1977年 | 8篇 |
| 1975年 | 7篇 |
| 1974年 | 6篇 |
| 1973年 | 3篇 |
| 1970年 | 4篇 |
排序方式： 共有10000条查询结果，搜索用时 31 毫秒
41.
Familial Congenital Methemoglobinemia in Pomeranian Dogs Caused by a Missense Variant in the NADH‐Cytochrome B5 Reductase Gene 
下载免费PDF全文
下载免费PDF全文 H. Shino Y. Otsuka‐Yamasaki T. Sato K. Ooi O. Inanami R. Sato M. Yamasaki 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):165-171
Background
In veterinary medicine, congenital methemoglobinemia associated with nicotinamide adenine dinucleotide (NADH)‐cytochrome b5 reductase (b5R) deficiency is rare. It has been reported in several breeds of dogs, but little information is available about its etiology.Objectives
To analyze the NADH‐cytochrome b5 reductase gene, CYB5R3, in a Pomeranian dog family with methemoglobinemia suspected to be caused by congenital b5R deficiency.Animals
Three Pomeranian dogs from a family with methemoglobinemia were analyzed. Five healthy beagles and 5 nonrelated Pomeranian dogs without methemoglobinemia were used as controls.Methods
Methemoglobin concentration, b5R activity, and reduced glutathione (GSH) concentration were measured, and a turbidity index was used to evaluate Heinz body formation. The CYB5R3 genes of the affected dog and healthy dogs were analyzed by direct sequencing.Results
Methemoglobin concentrations in erythrocytes of the affected dogs were remarkably higher than those of the control dogs. The b5R activity of the affected dogs was notably lower than that of the control dogs. DNA sequencing indicated that this Pomeranian family carried a CYB5R3 gene missense variant (ATC→CTC at codon 194) that resulted in the replacement of isoleucine (Ile) by leucine (Leu).Conclusions and Clinical Importance
This dog family had familial congenital methemoglobinemia caused by b5R deficiency, which resulted from a nonsynonymous variant in the CYB5R3 gene. This variation (c.580A>C) led to an amino acid substitution (p.Ile194Leu), and Ile194 was located in the proximal region of the NADH‐binding motif. Our data suggested that this variant in the canine CYB5R3 gene would affect function of the b5R in erythrocytes. 相似文献42.
Barriers to and enablers of implementing antimicrobial stewardship programs in veterinary practices 下载免费PDF全文
下载免费PDF全文 43.
44.
Serologic and fecal markers to predict response to induction therapy in dogs with idiopathic inflammatory bowel disease 下载免费PDF全文
下载免费PDF全文 45.
Immunohistochemical differentiation of reactive from malignant mesothelium as a diagnostic aid in canine pericardial disease 下载免费PDF全文
下载免费PDF全文 E. Milne Y. Martinez Pereira C. Muir T. Scase D. J. Shaw G. McGregor L. Oldroyd E. Scurrell M. Martin C. Devine H. Hodgkiss‐Geere 《The Journal of small animal practice》2018,59(5):261-271
Objectives
To develop a provisional immunohistochemistry panel for distinguishing reactive pericardium, atypical mesothelial proliferation and mesothelioma in dogs.Materials and Methods
Archived pericardial biopsies were subject to haematoxylin and eosin staining, immunohistochemistry for cytokeratin, vimentin, insulin‐like growth factor II mRNA‐binding protein 3, glucose transporter 1 and desmin. Samples were scored for intensity and number of cells stained.Results
Ten biopsies of reactive mesothelium, 17 of atypical mesothelial proliferation, 26 of mesothelioma and five of normal pericardium were identified on the basis of haematoxylin and eosin staining. Cytokeratin and vimentin were expressed in all biopsies, confirming mesothelial origin. Normal pericardial samples had the lowest scores for insulin‐like growth factor II mRNA‐binding protein 3, glucose transporter 1 and desmin. Mesothelioma and atypical proliferative samples were similar to each other, with higher scores for insulin‐like growth factor II mRNA‐binding protein 3 and glucose transporter 1 than the reactive samples. Desmin staining was variable. Insulin‐like growth factor II mRNA‐binding protein 3 was the best to distinguish between disease groups.Clinical Significance
An immunohistochemistry panel of cytokeratin, vimentin, insulin‐like growth factor II mRNA‐binding protein 3 and glucose transporter 1 could provide superior information compared with haematoxylin and eosin staining alone in the diagnosis of cases of mesothelial proliferation in canine pericardium, but further validation is warranted. 相似文献46.
47.
Eric Lim Teik Chung Michael Predith Frisco Nobilly Anjas Asmara Samsudin Faez Firdaus Abdullah Jesse Teck Chwen Loh 《Tropical animal health and production》2018,50(8):1727-1732
Brachiaria decumbens is an extremely productive tropical grass due to its aggressive growth habit and its adaptation to a varied range of soil types and environments. As a result of the vast availability, treated B. decumbens demonstrates as a promising local material that could be utilised as an improved diet for sheep and goats. Despite the fact that the grass significantly increases weight gains in grazing farm animals, there were many reports of general ill-thrift and sporadic outbreaks of photosensitivity in livestock due to the toxic compound of steroidal saponin found in B. decumbens. Ensiling and haymaking were found to be effective in removing toxin and undesirable compounds in the grass. Biological treatments using urea, activated charcoal, polyethylene glycol, and effective microorganisms were found to be useful in anti-nutritional factor deactivation and improving the nutritive values of feedstuffs. Besides, oral administration of phenobarbitone showed some degree of protection in sheep that fed on B. decumbens pasture. In this review, we aim to determine the effect of B. decumbens toxicity and possible treatment methods on the grass to be used as an improved diet for small ruminant. 相似文献
48.
B. Poźniak K. Motykiewicz‐Pers T. Grabowski M. Świtała 《Journal of veterinary pharmacology and therapeutics》2018,41(1):163-165
The aim of this study was to assess the influence of growth on the pharmacokinetics of sodium salicylate (SS) in male turkeys. SS was administered intravenously at a dose of 50 mg/kg. Plasma drug concentrations were assessed by high‐performance liquid chromatography, and pharmacokinetic parameters were calculated by noncompartmental analysis. As the age increased from 6 to 13 weeks (body weight increase from 2.35 to 9.43 kg), median body clearance decreased from 1.34 to 0.87 ml/min/kg. This caused a significant increase in the median mean residence time from 3.42 to 4.44 hr. Elimination phase proved to be biphasic and two elimination half‐lives (T1/2el) were distinguished. Whereas T1/2el1 was found to increase with age by 128%, T1/2el2 represented a later but faster and less age‐dependent phase of elimination (increase by 56% in the respective groups). Volume of distribution decreased with age. These effects may lead to different therapeutic response to SS in turkeys of different age and body weights. 相似文献
49.
50.
Incidence and risk factors for neurological signs after attenuation of single congenital portosystemic shunts in 253 dogs 下载免费PDF全文
下载免费PDF全文