全文获取类型
收费全文 | 367篇 |
免费 | 14篇 |
国内免费 | 7篇 |
专业分类
林业 | 46篇 |
农学 | 112篇 |
基础科学 | 9篇 |
17篇 | |
综合类 | 95篇 |
农作物 | 5篇 |
水产渔业 | 5篇 |
畜牧兽医 | 86篇 |
园艺 | 10篇 |
植物保护 | 3篇 |
出版年
2024年 | 24篇 |
2023年 | 31篇 |
2022年 | 19篇 |
2021年 | 21篇 |
2020年 | 30篇 |
2019年 | 27篇 |
2018年 | 10篇 |
2017年 | 5篇 |
2016年 | 17篇 |
2015年 | 17篇 |
2014年 | 20篇 |
2013年 | 11篇 |
2012年 | 18篇 |
2011年 | 14篇 |
2010年 | 1篇 |
2009年 | 7篇 |
2008年 | 3篇 |
2007年 | 4篇 |
2005年 | 4篇 |
2004年 | 3篇 |
2003年 | 78篇 |
2002年 | 2篇 |
2001年 | 6篇 |
2000年 | 8篇 |
1999年 | 5篇 |
1993年 | 1篇 |
1964年 | 2篇 |
排序方式: 共有388条查询结果,搜索用时 265 毫秒
91.
为进一步加强非洲猪瘟防控工作,新疆开展了非洲猪瘟专项监测排查,2018年12月5日,在公路检查站拦截的A厂5个批次速冻水饺样品中,首次检出非洲猪瘟病毒核酸。为防止携带非洲猪瘟病毒的猪肉产品引发疫情,针对公路检查站、冷库及超市的猪肉馅水饺进行排查,随后又在B厂4个批次水饺中检出非洲猪瘟病毒核酸。这是新疆首次连续集中在外地输入的猪肉馅水饺中发现非洲猪瘟病毒,说明非洲猪瘟病毒已形成了一定污染面。因此,要加强产地检疫和屠宰场的实验室检测,继续加大跨省入疆猪肉及其产品的检查和查处力度,严格控制疫区生猪及猪肉产品调入新疆。 相似文献
92.
开心果树,也叫阿月浑子,并非为我国原产的苗木种类,所以内地及沿海地区的人都不怎么熟悉,而在叙利亚等国开心果树则被很普遍种植。开心果树怕涝,抗旱。开心果既有经济价值,又有防风节水的作用,因此,在吐鲁番地区种植开心果有较好的发展前景。 相似文献
93.
94.
Eskelinen EV Liska WD Hyyti?inen HK Hielm-Bj?rkman A 《Veterinary and comparative orthopaedics and traumatology》2012,25(5):427-432
A 27-kg German Shorthaired Pointer was referred for evaluation due to the complaint of left pelvic limb lameness and signs of pain in the left stifle joint. Radiographs revealed signs of a healed supracondylar femoral fracture that had been previously repaired at another hospital with an intramedullary pin and two cross pins. In addition, there were signs of severe osteoarthritis (OA). The OA had been managed medically with administration of carprofen and nutraceuticals for nine months without any improvement. Left total knee replacement (TKR) surgery was performed to alleviate signs of pain. The patient was assessed preoperatively and at six months, one year, and two years after surgery using radiology, force platform analysis of gait, thigh circumference measures, goniometry, and lameness evaluation. Following surgery, the dog resumed normal activity without any signs of pain and a good quality of life at 3.5 months. Force plate analysis found that peak vertical force on the TKR limb was 85.7% of the normal contralateral limb after two years. Total knee replacement was a successful treatment to manage knee OA associated with a healed distal femoral fracture and internal fixation in this dog. 相似文献
95.
Smith TJ Baltzer WI L?hr C Stieger-Vanegas SM 《Veterinary and comparative orthopaedics and traumatology》2012,25(2):160-166
A two-year-old, 97 kg, male neutered English Mastiff was evaluated for left pelvic limb lameness of five months duration localized to the stifle joint. Following radiographic, computed tomographic and arthroscopic examination, the lameness was subsequently diagnosed as being caused by primary synovial osteochondromatosis. In total, 194 osteochondral bodies were removed using arthroscopy in combination with a mini-arthrotomy. Histology and immunohistochemistry of the loose osteochondral fragments confirmed the diagnosis with a moderately high degree of differentiation and low cellularity. Nuclear staining for Ki-67 revealed decreasing differentiation and increasing cellularity in the fragments. At the 13 months telephone follow-up the owner reported that the dog was free from lameness and had a vastly improved function compared with preoperative levels, although mild lameness did occasionally occur. This is the first report of computed tomography, arthroscopy and immunohistochemistry confirming a case of primary synovial osteochondromatosis in a dog. 相似文献
96.
以库尔勒香梨树干形成层为主要研究对象,测定越冬期间香梨树干形成层、树枝及花芽组织保护酶活性变化特性,对比分析日灼组织保护性酶活性的影响.结果表明,在越冬期间形成层过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)的活性随着温度的降低而升高;阳面、阴面、树枝和芽的SOD活性差异不显著,但POD、CAT活性具有显著差异;日灼通过影响树干形成层温度导致树干形成层南北侧保护酶活性的差异,阳面酶活性较高 相似文献
97.
ZHONG Yuan? chang 《保鲜与加工》2003,(2):22-24
To analyse the working parameter of switched power, this article introduces the circuit model of switched power and the shaping process of its on off voltage wave. Aiming at analyzing to the voltage wave and parameter, an "assistant compensation" method is put forward. Based on this method, the voltage wave and parameter of switched power are theoretically analyzed and imitated. The imitation results indicate that the method is afeasible and advance one. 相似文献
98.
湍杆咏幌低?为筛选番茄cDNA 《贵州农业科学》2007,(6)
jing 100081)The Magnaporthe grisea protein elicitor pemG1 gene was amplified by PCR with the EcoR I and Xho I restriction sites incorporated into the primers,digested by restriction enzymes and ligated with the vector pLexA to construct recombinant bait plasmid pLexA-PEMG1.After the transform of recombinant plasmid into yeast strain EGY48[p8op-lacZ],the autonomous report 相似文献
99.
100.
Smart antenna is one of the key technique in the third generation mobile telecommunication system. Main estimation methods for DOA(direction of arrival),i.e. ESPRIT, MUSIC, WSF, Mininorm,etc., are researched,the performances for DOA estimation based on smart antenna are analyzed by the research of theory, simulation experiment and the contrast algorithms between and Cramer Rao Bound.The research results aren't only propitious to research and develop for smart antenna,but also for the application of smart antenna in mobile telecommunication. 相似文献