全文获取类型
收费全文 | 953篇 |
免费 | 66篇 |
国内免费 | 122篇 |
专业分类
林业 | 101篇 |
农学 | 161篇 |
基础科学 | 76篇 |
192篇 | |
综合类 | 270篇 |
农作物 | 33篇 |
水产渔业 | 35篇 |
畜牧兽医 | 169篇 |
园艺 | 36篇 |
植物保护 | 68篇 |
出版年
2024年 | 15篇 |
2023年 | 11篇 |
2022年 | 35篇 |
2021年 | 35篇 |
2020年 | 34篇 |
2019年 | 41篇 |
2018年 | 38篇 |
2017年 | 36篇 |
2016年 | 47篇 |
2015年 | 41篇 |
2014年 | 39篇 |
2013年 | 45篇 |
2012年 | 69篇 |
2011年 | 58篇 |
2010年 | 56篇 |
2009年 | 46篇 |
2008年 | 51篇 |
2007年 | 49篇 |
2006年 | 39篇 |
2005年 | 56篇 |
2004年 | 28篇 |
2003年 | 19篇 |
2002年 | 13篇 |
2001年 | 16篇 |
2000年 | 28篇 |
1999年 | 28篇 |
1998年 | 21篇 |
1997年 | 26篇 |
1996年 | 20篇 |
1995年 | 20篇 |
1994年 | 12篇 |
1993年 | 17篇 |
1992年 | 12篇 |
1991年 | 9篇 |
1990年 | 10篇 |
1989年 | 10篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有1141条查询结果,搜索用时 15 毫秒
1.
I. Srugo O. Chai D. Yaakov L. Sharon M. H. Shamir 《The Journal of small animal practice》2010,51(8):447-450
Thoracolumbar disc herniation was diagnosed in a two-year-old ferret using a myelogram followed by a computed tomography scan. The ferret was paraplegic with no control over urination and defecation. Conservative treatment that included cage rest and passive range of motion exercises for three weeks followed by extensive physiotherapy and hydrotherapy resulted in full recovery two months after the onset of treatment. Although intervertebral disc disease has been reported previously in four ferrets, this is the first report in which a postmyelogram computed tomography was used to demonstrate the herniated disc, and physiotherapy was used as principal treatment modality. 相似文献
2.
3.
在研制猪细小病毒灭活疫苗时,应用了超滤浓缩技术,提高了合毒细胞培养液中的抗原含量。为了保证浓缩的流量,减少对滤膜的污染,对含毒细胞培养液作了预处理一离心及微滤,以便除去细胞培养液中的细胞碎片、蛋白质等大分子物质及固形微粒。超滤时选用50000Da滤膜,在20psig压力下,经过5倍浓缩的PPV细胞培养液,血凝滴度提高2个滴度以上。病毒含量测定表明,TCID50/0.2mL由107左右升至109以上,以其配制疫苗,能显著地提高疫苗的免疫原性。超滤技术具有易于操作、高效、分离精度高、没有二次污染等优点,可以根据需要选择不同的浓缩浓度,对保证疫苗的质量具有重要作用。 相似文献
4.
Objective— To evaluate the use of a modified K-wire spacer for maintaining intervertebral distraction after ventral decompression and during stabilization as a treatment for disc-associated wobbler syndrome in large breed dogs.
Study Design— A retrospective study.
Animals— Dogs (n=7) with disc-associated wobbler syndrome.
Methods— Medical records (2003–2006) of dogs treated by a modified surgical method were evaluated. Data retrieved were signalment, onset and duration of clinical signs, neurologic abnormalities, diagnostic methods, surgical procedure, immediate, and long-term (≥1 year) postoperative clinical and radiographic outcome.
Results— Mean duration of clinical signs was 4.8 months. Neurologic signs included ataxia (2), ambulatory tetraparesis (2), and non-ambulatory tetraparesis (3). Three dogs had disc protrusion in 2 sites, 2 dogs had the procedure in 1 location and stabilization of both affected sites. All dogs improved dramatically and remained for 1–3 years. One dog had recurrence of cervical discomfort 13 months later.
Conclusions— Despite the limited number of dogs, overall initial successful outcome with only 1 dog having mild recurrence 13 months later supports further use and evaluation of this technique.
Clinical Relevance— Distraction using a K-wire spacer after ventral decompression followed by stabilization should be considered in dogs with disc-associated wobbler syndrome to prevent collapse of the intervertebral space. 相似文献
Study Design— A retrospective study.
Animals— Dogs (n=7) with disc-associated wobbler syndrome.
Methods— Medical records (2003–2006) of dogs treated by a modified surgical method were evaluated. Data retrieved were signalment, onset and duration of clinical signs, neurologic abnormalities, diagnostic methods, surgical procedure, immediate, and long-term (≥1 year) postoperative clinical and radiographic outcome.
Results— Mean duration of clinical signs was 4.8 months. Neurologic signs included ataxia (2), ambulatory tetraparesis (2), and non-ambulatory tetraparesis (3). Three dogs had disc protrusion in 2 sites, 2 dogs had the procedure in 1 location and stabilization of both affected sites. All dogs improved dramatically and remained for 1–3 years. One dog had recurrence of cervical discomfort 13 months later.
Conclusions— Despite the limited number of dogs, overall initial successful outcome with only 1 dog having mild recurrence 13 months later supports further use and evaluation of this technique.
Clinical Relevance— Distraction using a K-wire spacer after ventral decompression followed by stabilization should be considered in dogs with disc-associated wobbler syndrome to prevent collapse of the intervertebral space. 相似文献
5.
Itai Barnoon Orit Chai Itai Srugo Dana Peeri Lilach Konstantin Ori Brenner Merav H. Shamir 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(11):1191-1194
Myelo-computed tomography of a paraparetic 14-year-old dog revealed subarachnoid distension with an intradural filling defect above the T13–L1 disc space. T12–L1 hemilaminectomy followed by durotomy allowed removal of a large piece of degenerated disc material that compressed the spinal parenchyma. Full return to function was achieved 10 days post-surgery. The distension was likely secondary to the intradural herniation, and is a rare and distinct finding. 相似文献
6.
7.
欧洲动物生产与营养研究的现状和发展趋势 总被引:5,自引:0,他引:5
本作在欧洲从事博士后研究期间,几次参加相关学术讨论会,并接触到一些反映最新发展趋势的资料和信息.在此基础上,结合作本人对相关问题的思考,撰写了本篇章.本从21世纪动物生产面临的新问题、新挑战出发,论述了动物生产的新进展和新要求,动物营养研究应用的新技术和新方法,目前动物生产与营养研究的领域和热点问题等,概略论述了目前欧洲动物生产与营养研究的现状和发展趋势,供有关人员参考。 相似文献
8.
Xiaoliang Li Yiliang Lu Liming Li Xinyu Chai Qiushi Ren 《Veterinary ophthalmology》2010,13(2):131-135
Multi‐channel visual evoked potential (MVEP) recording method was used to assist in diagnosing a 4‐month‐old Chinese Albino rabbit with an intraorbital mass. Subcutaneous MVEP of its both eyes were recorded simultaneously using 16 electrodes (4 × 4) multi‐channel array. Analysis of the cortical potential landscapes (CPL) showed that the conduction function of right eye was remarkably impaired in terms of decreased amplitudes and prolonged latencies. Specific side‐dominant distribution asymmetry of the decreased MVEP amplitudes indicated that the temporal side of the optic nerve (ON) was severely involved. Overall prolonged latencies of the CPL without side differences suggested that the functional impairment could have been caused by the mechanical compression exerted by an intraorbital mass. Surgical removal procedures confirmed that the mass was located temporally to the ON. Pathological examination provided a final diagnosis of a giant polycystic mucocele. Beyond its significance as a standard tool to assess functional changes of the visual pathway, MVEP recordings might assist locating intraorbital lesions that involve the ON by careful analysis of abnormal CPLs. 相似文献
9.
浅谈培育和发展烤烟大户 总被引:3,自引:0,他引:3
该文论述了培育和发展烤烟大户在现代烟草农业建设中作用:其一是实现农用土地流转的重要形式;其二是实现现代烟草农业规模化生产的必由之路;其三是实现现代烟草农业专业化生产的桥梁。 相似文献
10.