全文获取类型
收费全文 | 479篇 |
免费 | 34篇 |
专业分类
林业 | 37篇 |
农学 | 11篇 |
87篇 | |
综合类 | 16篇 |
农作物 | 36篇 |
水产渔业 | 56篇 |
畜牧兽医 | 215篇 |
园艺 | 8篇 |
植物保护 | 47篇 |
出版年
2023年 | 3篇 |
2022年 | 17篇 |
2021年 | 45篇 |
2020年 | 37篇 |
2019年 | 33篇 |
2018年 | 30篇 |
2017年 | 22篇 |
2016年 | 32篇 |
2015年 | 15篇 |
2014年 | 24篇 |
2013年 | 33篇 |
2012年 | 34篇 |
2011年 | 37篇 |
2010年 | 19篇 |
2009年 | 19篇 |
2008年 | 28篇 |
2007年 | 22篇 |
2006年 | 14篇 |
2005年 | 15篇 |
2004年 | 19篇 |
2003年 | 5篇 |
2002年 | 8篇 |
2000年 | 2篇 |
排序方式: 共有513条查询结果,搜索用时 15 毫秒
431.
Candice Schmidt Juliana F. Cargnelutti Mário C.S. Brum Carolina K. Traesel Rudi Weiblen Eduardo F. Flores 《Veterinary microbiology》2013
We herein describe the partial nucleotide sequencing and phylogenetic analysis of the B2L gene of seventeen Brazilian orf viruses (ORFV). Seventeen viruses were recovered from outbreaks of contagious ecthyma in sheep and goats in four states in Southern and Northeast country, and three from commercial vaccines. Most analyzed viruses were associated with outbreaks of classical contagious ecthyma, with lip, nostrils and labial commissure involvement, yet udder/teat, feet, vulvar and disseminated lesions were also reported in some cases. Nucleotide sequence analysis revealed a high degree of B2L similarity among sheep sequences (>99%) regardless the geographic origin, and a remarkable high identity for the two goat isolates (>99.8%), with similarity dropping to below 99% when comparing viruses from the two species. A phylogenetic tree grouped most sheep and goat viruses on different branches. In addition, sequence alignment allowed the identification of up to six scattered nucleotide changes that were predominant and more consistent in goat isolates, including a number of sequences from other continents. Thus, in spite of the high nucleotide similarity, different degrees of similarity and discrete nucleotide changes in the B2L gene may help in grouping ORFV viruses according to host species. 相似文献
432.
Maria Miró-Arias Juan Maria Gallardo Bolaños Antolin Morillo-Rodríguez Carolina Balao da Silva Ines Maria Aparicio Jose Antonio Tapia Angel Vallecillo Jose Luis Vega-Pla Fernando Juan Peña Vega Cristina Ortega Ferrusola 《Journal of Equine Veterinary Science》2013
In order to determine whether the high level of inbreeding of the Retuertas endangered Horses may increase the vulnerability to oxidative stress of the sperm, the susceptibility to lipid peroxidation (LPO) of sperm membranes was evaluated in cooled extended ejaculates. Extended ejaculates (INRA 96) from four Retuertas horses and nine ejaculates from pure Spanish horses were received within 24 hours of collection at our laboratory. An aliquot was analyzed and served as time 0 control. The rest of the ejaculates were split into two additional aliquots: the first aliquot served as an incubation control and the second aliquot received an oxidative insult (Fe2SO4). Membrane LPO, motility parameters, membrane integrity, and mitochondrial membrane potential were evaluated. The oxidative insult induced a significant increase in the percentage of sperm with LPO in the Retuertas horses (P < .05). Total and progressive motility were not affected by the oxidative insult in both groups. However, curvilinear velocity (VCL), average velocity (VAP), straightness index (STR), and amplitude of lateral head displacement (ALH) were significantly affected by the treatment (P < .05) in the Retuertas horse population. The membrane integrity of sperm in this group was also affected: the percentage of sperm with intact membranes decreased (57.31% ± 7.76% vs. 47.52% ± 8.28%); and the percentage of necrotic sperm increased (33.27% ± 7.83% vs. 44.85% ± 9.16%) (P < .05). Finally, the oxidative insult increased the population with low mitochondrial membrane potential in these wild horses. We concluded that the high level of inbreeding of this particular breed apparently leads to a higher susceptibility to lipid peroxidation. 相似文献
433.
Effect of storage conditions on subpopulations of peripheral blood T lymphocytes isolated from naïve cattle and cattle infected with foot‐and‐mouth disease virus
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)
434.
Ramírez Olga Lucia Herrán Santos Huarrisson Azevedo Paulino Patrícia Gonzaga van der Meer Carolina Soares Bautista José Luis Rodríguez Delgado Ingrid Lorena Jaramillo Obando Juliana González Garcia Rene Ramirez da Costa Angelo Isabele 《Veterinary research communications》2022,46(1):189-201
Veterinary Research Communications - A cross-sectional study was conducted in Colombia to recover Brucella spp. DNA from bovine whole-blood samples through probe-based real-time PCR (qPCR). By an... 相似文献
435.
Elcio L. Balota Oswaldo Machineski Carolina Honda Ines F. U. Yada Graziela M. C. Barbosa Andre S. Nakatani Mark S. Coyne 《Land Degradation \u0026amp; Development》2016,27(4):1141-1150
Swine slurry is a common agricultural fertilizer in many countries. However, its long‐term use in large amounts can cause excess nutrient accumulation, alter soil compounds, and potentially influence critical microbial populations such as arbuscular mycorrhizal fungi, which have important roles in plant nutrition and soil sustainability. This work determined if arbuscular mycorrhizal status, external mycelium, and glomalin‐related soil protein content were affected by long‐term swine slurry application to different soil tillage systems. The experiment was conducted on a clayey oxisol, in southern Brazil. Swine slurry (0, 30, 60, 90, and 120 m3 ha−1 y−1) was applied for 15 years to conventional tillage and no tillage soil prior to the summer (soybean or maize) and winter (wheat or oats) crop seasons. Swine slurry decreased mycorrhizal root colonization, spore number, and total external mycelium. Swine slurry increased active external mycelium and both easily extractable and total glomalin‐related soil protein. No‐tillage soil had more glomalin‐related soil protein than conventional tillage soil. The most significant response variables were root colonization, easily extractable glomalin‐related soil protein, and total external arbuscular mycorrhizal mycelia. Long‐term application of swine slurry in this environment, even at high rates, did not adversely affect crop yield but did influence arbuscular mycorrhizae fungi and their products in the soil environment. Benefits of swine slurry application for crop nutrition must be weighed against potential adverse consequences for the size, activity, and benefits of the mycorrhizal community to subsequent annual crops. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
436.
Serres F Chetboul V Tissier R Sampedrano CC Gouni V Nicolle AP Pouchelon JL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(2):258-264
Background:Degenerative mitral valve disease (MVD) is the most common heart disease in small breed dogs, and chordae tendineae rupture (CTR) is a potential complication of this disease. The survival time and prognostic factors predictive of survival in dogs with CTR remain unknown.
Hypothesis:The prevalence and prognosis of CTR in dogs with MVD increases and decreases, respectively, with heart failure class.
Animals:This study used 706 dogs with MVD.
Methods:The diagnosis of CTR was based on a flail mitral leaflet with the tip pointing into the left atrium during systole, which was confirmed in several 2-dimension imaging planes using the left and right parasternal 4-chamber views.
Results:CTR was diagnosed in 114 of the 706 dogs with MVD (16.1%) and most of these (106/114, 93%) had severe mitral valve regurgitation as assessed by color Doppler mode. CTR prevalence increased with International Small Animal Cardiac Health Council (ISACHC) clinical class (i.e., 1.9, 20.8, 35.5, and 69.6% for ISACHC classes Ia, Ib, II, and III, respectively [ P < .05]). Long-term follow-up was available for 57 treated dogs (angiotensin-converting enzyme inhibitors and diuretics) and 58% of these (33/57) survived > 1 year after initial CTR diagnosis (median survival time, 425 days). Clinical class, the presence of ascites or acute dyspnea at the time of diagnosis, heart rate, plasma urea concentration, and left atrial size were predictors of survival.
Conclusions and Clinical Relevance: CTR is associated with a higher overall survival time than previously supposed. Its prognosis mostly depends on a combination of clinical and biochemical factors. 相似文献
Hypothesis:The prevalence and prognosis of CTR in dogs with MVD increases and decreases, respectively, with heart failure class.
Animals:This study used 706 dogs with MVD.
Methods:The diagnosis of CTR was based on a flail mitral leaflet with the tip pointing into the left atrium during systole, which was confirmed in several 2-dimension imaging planes using the left and right parasternal 4-chamber views.
Results:CTR was diagnosed in 114 of the 706 dogs with MVD (16.1%) and most of these (106/114, 93%) had severe mitral valve regurgitation as assessed by color Doppler mode. CTR prevalence increased with International Small Animal Cardiac Health Council (ISACHC) clinical class (i.e., 1.9, 20.8, 35.5, and 69.6% for ISACHC classes Ia, Ib, II, and III, respectively [ P < .05]). Long-term follow-up was available for 57 treated dogs (angiotensin-converting enzyme inhibitors and diuretics) and 58% of these (33/57) survived > 1 year after initial CTR diagnosis (median survival time, 425 days). Clinical class, the presence of ascites or acute dyspnea at the time of diagnosis, heart rate, plasma urea concentration, and left atrial size were predictors of survival.
Conclusions and Clinical Relevance: CTR is associated with a higher overall survival time than previously supposed. Its prognosis mostly depends on a combination of clinical and biochemical factors. 相似文献
437.
OBJECTIVE: To determine proviral load in bovine leukemia virus (BLV)-infected cattle with and without persistent lymphocytosis to assess the potential of transmitting the virus. ANIMALS: Cattle in 6 dairy herds. PROCEDURES: Blood samples from infected cows were evaluated 3 times at 6-month intervals for determination of proviral load via PCR assay, serologic results via ELISA, and hematologic status via differential cell counts. RESULTS: Infected cattle were classified into lymphocytotic and nonlymphocytotic groups. Lymphocytotic cattle consistently had > 100,000 copies of integrated provirus/mug of DNA (ie, high proviral load) in peripheral blood leukocytes. Titers of antibodies against BLVgp51 and BLVp24 indicated a strong immune response. Nonlymphocytotic cattle comprised 2 subgroups: a group with high proviral load and strong immune response, and a group with a weaker immune response, mostly against BLVp24, and a proviral load of < 100 copies/microg of DNA (ie, low proviral load). CONCLUSIONS AND CLINICAL RELEVANCE: Results emphasized the importance of characterizing nonlymphocytotic BLV-infected cattle during eradication programs. The risk of transmitting BLV infection from nonlymphocytotic cattle may differ depending on the proviral load. Nonlymphocytotic cattle with high proviral load could be efficient transmitters (as efficient as lymphocytotic cattle), whereas nonlymphocytotic cattle with low proviral load could be inefficient transmitters under standard husbandry conditions. Because most cattle with low proviral load do not develop anti-BLVp24 antibodies, it appears that lack of an anti-BLVp24 antibody response may be a good marker of this condition. 相似文献
438.
Behr L Chetboul V Sampedrano CC Vassiliki G Pouchelon JL Laborde F Borenstein N 《Veterinary surgery : VS》2007,36(3):190-198
OBJECTIVES: To describe an open, beating heart surgical technique and use of a bovine pericardial prosthetic valve for mitral valve replacement (MVR) in the dog. STUDY DESIGN: Clinical case report. ANIMALS: Male Bull Terrier (17-month-old, 26 kg) with mitral valve dysplasia and severe regurgitation. METHODS: A bovine pericardial bioprosthesis was used to replace the mitral valve using an open beating heart surgical technique and cardiopulmonary bypass. RESULTS: Successful MVR was achieved using a beating heart technique. Mitral regurgitation resolved and cardiac performances improved (left ventricular end-diastolic diameter decreased from 57.6 to 48.7 mm, and left atrium/aorta ratio returned to almost normal, from 1.62 to 1.19). Cardiopulmonary by-pass time and total surgical duration were decreased compared with standard cardioplegic techniques. Surgical recovery was uneventful and on echocardiography 6 months later valve function was excellent. CONCLUSION: Considering the technique advantages (no cardiac arrest, ischemic reperfusion injury, and hypothermia, or the need for aortic dissection and cannulation for administration of cardioplegic solution), short-term mortality and morbidity may be reduced compared with standard cardioplegic techniques. CLINICAL RELEVANCE: Based on experience in this dog, beating heart mitral valvular replacement is a seemingly safe and viable option for the dog and bovine pericardial prosthesis may provide better long-term survival than mechanical prostheses. 相似文献
439.
Nicholas T. Jenkins Gustavo Pe?a Carlos Risco Carolina C. Barbosa Achilles Vieira-Neto Klibs N. Galv?o 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(8):850-854
The objective was to identify a fat-to-protein ratio (FPR) cut-off to diagnose subclinical ketosis (SCK) and to evaluate the effect of propylene glycol (PPG) treatment of cows with high FPR. The optimized cut-off was > 1.42; sensitivity (Se) = 92%; specificity (Sp) = 65%. A cut-off > 1.5 was selected for the PPG trial for balanced Se-Sp. Fat-to-protein ratio cut-offs > 1.25, 1.35, 1.50, 1.60, and 1.70 resulted in Se-Sp of 100% to 49%, 96% to 59%, 75% to 78%, 33% to 90%, and 8% to 96%, respectively. The proportions of cows with FPR > 1.25, 1.35, 1.42, 1.50, 1.60, and 1.70 were 60%, 50%, 44%, 30%, 14%, and 6%, respectively. Incidences of clinical ketosis and milk yield were similar between cows that received 400 mL of PPG (n = 34) and control cows (n = 38). Prevalence of SCK at enrollment was 29.2%; therefore, FPR > 1.5 is not indicated for treatment. Lower cut-offs should be used for screening. 相似文献
440.
Jurandy Mauro Penitente‐Filho Carolina Rodrigues Jimenez Adriana Moreira Zolini Erly Carrascal Jovana Luiza Azevedo Camila Oliveira Silveira Fabrício Albani Oliveira Ciro Alexandre Alves Torres 《Animal Science Journal》2015,86(2):148-152
In order to evaluate whether ovarian volume, presence and diameter of the corpus luteum (CL) have effects on the number and quality of bovine recovered oocytes, 110 ovaries were obtained from the slaughterhouse. Cumulus oocytes complex were aspirated and evaluated under stereomicroscope. Oocytes were counted and classified according to their quality (Grades I, II, III and IV). Ovarian volume was weakly correlated to the number of good quality oocytes (P < 0.05). Ovaries with CL showed greater numbers of good quality oocytes than ovaries without CL (P < 0.05). Further, presence of CL and its diameter positively influenced the probability of recovering good quality oocytes (P < 0.05). In conclusion, ovarian volume is not a good parameter itself to predict important ovarian characteristics; moreover, analysis of CL, its presence and diameter, may be a good tool to improve efficiency on in vitro embryo production programs. 相似文献