全文获取类型
收费全文 | 30293篇 |
免费 | 1282篇 |
国内免费 | 8篇 |
专业分类
林业 | 1070篇 |
农学 | 892篇 |
基础科学 | 174篇 |
4561篇 | |
综合类 | 3980篇 |
农作物 | 1165篇 |
水产渔业 | 1146篇 |
畜牧兽医 | 16481篇 |
园艺 | 335篇 |
植物保护 | 1779篇 |
出版年
2021年 | 224篇 |
2020年 | 265篇 |
2019年 | 331篇 |
2018年 | 600篇 |
2017年 | 664篇 |
2016年 | 566篇 |
2015年 | 364篇 |
2014年 | 552篇 |
2013年 | 1662篇 |
2012年 | 863篇 |
2011年 | 1114篇 |
2010年 | 808篇 |
2009年 | 761篇 |
2008年 | 1077篇 |
2007年 | 1053篇 |
2006年 | 890篇 |
2005年 | 713篇 |
2004年 | 721篇 |
2003年 | 661篇 |
2002年 | 584篇 |
2001年 | 744篇 |
2000年 | 743篇 |
1999年 | 544篇 |
1998年 | 244篇 |
1997年 | 227篇 |
1995年 | 269篇 |
1992年 | 400篇 |
1991年 | 415篇 |
1990年 | 432篇 |
1989年 | 440篇 |
1988年 | 344篇 |
1987年 | 353篇 |
1986年 | 383篇 |
1985年 | 342篇 |
1984年 | 331篇 |
1983年 | 303篇 |
1979年 | 481篇 |
1978年 | 328篇 |
1977年 | 370篇 |
1976年 | 468篇 |
1975年 | 485篇 |
1974年 | 523篇 |
1973年 | 480篇 |
1972年 | 438篇 |
1971年 | 354篇 |
1970年 | 372篇 |
1969年 | 434篇 |
1968年 | 441篇 |
1967年 | 446篇 |
1966年 | 438篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
V K Singh 《The Indian veterinary journal》1970,47(10):913-914
992.
993.
Maduromycosis (Allescheria boydii) in a dog 总被引:2,自引:0,他引:2
H J Kurtz D R Finco V Perman 《Journal of the American Veterinary Medical Association》1970,157(7):917-921
994.
995.
Katheryn L. Cerny Tom V. Little Charles F. Scoggin Robert J. Coleman Mats H.T. Troedsson Edward L. Squires 《Journal of Equine Veterinary Science》2014
The current field study used thoroughbred stallions and mares from central Kentucky to investigate the occurrence of potentially pathogenic bacteria on the stallion's external genitalia, based on cultures, and investigated the occurrence of bacteria and type of isolate in the mare's uterus after breeding by live cover to stallions with or without positive bacterial cultures. Fifteen thoroughbred stallions and 206 mares from two central Kentucky thoroughbred farms were used during the 2010 and 2011 breeding seasons. Samples for bacteriological evaluation were taken from the prepuce and postejaculate urethra (n = 201) of stallions. Uterine swabs (n = 264) were collected 12-18 hours postbreeding. For statistical analyses, a chi-squared test was used to test the relationship between stallion culture results and postbreeding uterine culture results, as well as the effect of bacterial types found on the stallion cultures with bacterial types found on the postbreeding uterine cultures. Of stallion cultures, 22.4% were positive for potentially pathogenic bacteria, with Streptococcus equi subspecies zooepidemicus (51.1%) being the most common isolate. Uterine cultures resulted in a 29.2% positive rate for potentially pathogenic bacteria, with S. equi subsp. zooepidemicus (90.9%) being the most common. There was no difference (P > .05) in the occurrence of bacteria or type of isolate found on uterine cultures after breeding stallions with or without positive cultures. In conclusion, potentially pathogenic bacteria found on the stallion's external genitalia did not affect the occurrence and type of bacterial isolate found in the mare's uterus after breeding by live cover. 相似文献
996.
Pedro V. Michelotto Jr. Luis F.C. BastosCristina S. Sotomaior DVM PhD Cláudia T. Pimpão DVM PhD 《Journal of Equine Veterinary Science》2014
The stifle is a large and complex joint in quadrupeds, including horses, making the diagnosis of stifle diseases a challenge for the clinician. The detection of “stifle syndrome” during acupuncture examination of the equine stifle may be useful for diagnosis of stifle diseases in horses. The aim of the present study was to describe stifle syndrome diagnosis in horses. From 2001 through 2012, 810 athletic horses involved in different disciplines were examined using the technique of acupuncture diagnosis. Stifle syndrome was suspected when the following points were reactive: the sacral point suggestive of stifle disease located at the sacral origin of the biceps femoris muscle, bladder (BL)-20, BL-21, and stomach (ST)-30, together with the three local points in the muscle groove of the posterolateral aspect of the thigh. The diagnostic protocol included radiography and/or ultrasonography in certain cases. The horses were evaluated because of reduced athletic performance, routine or prepurchase examination, hind limb lameness, refusal to jump, inappetence, upward fixation of the patella, thoracolumbar spine or sacroiliac pain, suspensory lesion, and front hoof problems, and 86 (9.4%) were diagnosed with stifle syndrome. The sacral acupuncture point suggestive of stifle syndrome correlated with BL-21, local stifle points, gall bladder (GB)-27, spleen-13, BL-23, BL-52, BL-26, and/or GB-25, ST-30, BL-54 (P < .0001), and BL-20 (P = .003). Twenty-two (25.6%) of the 86 horses with stifle syndrome underwent ultrasonography and/or radiography, and lesions were detected in 21. In conclusion, acupuncture for diagnosis of stifle disease may be considered a diagnostic method to be included in routine clinical examination of horses, and its reproducibility shall be investigated in further studies. 相似文献
997.
998.
Effects of two commercial diets and technical feed treatment on stomach lesions and immune system of fattening pigs 下载免费PDF全文
W. Liermann A. Berk J. Frahm V. Böschen S. Dänicke 《Journal of animal physiology and animal nutrition》2017,101(5):e414-e426
The impact of technical feed treatment and diet on stomach lesions and traits of the local and systemic immune system were investigated in fattening pigs. Feeding groups differed in technical feed treatment (standard ground meal vs. finely ground and pelleted feed) and diet (soya bean meal vs. rapeseed meal/DDGS/soya beans). Pigs were fattened approximately 10 weeks by ad libitum feeding and slaughtered subsequently. Gastric alterations were assessed by a macroscopic scoring system [macroscopic stomach score (MSC) 0 = normal to 4 = severe lesions]. For immunological investigations, lymphocytes from blood and jejunal tissues were isolated. T‐cell phenotyping was carried out by staining intestinal lymphocytes with monoclonal antibodies for CD4 and CD8 and flow cytometric measurements. MSC was higher in animals fed finely ground and pelleted feed compared with their counterparts. Significant interactions between diet and feed treatment considering the MSC were observed (p = 0.027). There was no effect of diet or technical feed treatment on T cells of blood, Lymphonodi gastrici or lamina propria (LP) and intraepithelial cells. However, technical feed treatment significantly affected subsets of CD4+, CD8+, CD8low, CD4/CD8 double‐positive T cells, the mean fluorescence intensity of CD4+ T cells and the ratio of CD8low/CD8high T cells in Peyer's patches (PP). All named parameters were reduced in PP of animals fed finely ground and pelleted feed compared with animals fed standard ground meal. Furthermore, significant differences between T cells of lymph nodes and LP were observed between animals with middle MSC (MSC = 1–2.5) and animals with high MSC (MSC = 3–4). Significant alterations in T cells of PP were observed between animals of low (MSC = 0–0.5) and high MSC. The observed effects provide the evidence that the impact of technical feed treatment is not limited on the stomach lesions. Possible stimuli and consequences of the immune system should be studied in more detail. 相似文献
999.
1000.
N. Hovanessian J.L. Davis H.C. McKenzie J.L. Hodgson D.R. Hodgson M.V. Crisman 《Journal of veterinary pharmacology and therapeutics》2014,37(3):243-251
The purpose of this study was to determine the pharmacokinetics and safety profile of firocoxib in neonatal foals. Seven healthy foals were administered 0.1 mg/kg firocoxib orally q24 h for nine consecutive days, commencing at 36 h of age. Blood was collected for firocoxib analysis using high‐pressure liquid chromatography with fluorescence detection at 0 (dose #1 only), 0.25, 0.5, 1, 2, 4, 8, 16, and 24 h after doses 1, 5, and 9. For all other doses (2, 3, 4, 6, 7, and 8), blood was collected immediately prior to the next dose (24 h trough). Elimination samples (36, 48, 72, 96, 120, and 144 h) were collected after dose 9. Safety was assessed via physical examinations, body weight measurements, gastroscopy, complete blood count, plasma biochemistry and urinalysis. Firocoxib was rapidly absorbed following oral administration with minimal accumulation after repeat dosing. After the final dose, the terminal half‐life was approximately 11 h. Firocoxib was below the limit of detection (<2.5 ng/mL) in plasma 72 h after the final dose. No significant abnormalities were found on blood analyses, urinalysis, or gastroscopy. This study demonstrated that firocoxib is absorbed in neonatal foals with no demonstrable adverse effects after repeated doses of 0.1 mg/kg. 相似文献