全文获取类型
收费全文 | 244篇 |
免费 | 16篇 |
专业分类
林业 | 1篇 |
农学 | 7篇 |
综合类 | 33篇 |
农作物 | 5篇 |
水产渔业 | 4篇 |
畜牧兽医 | 201篇 |
植物保护 | 9篇 |
出版年
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 10篇 |
2012年 | 5篇 |
2011年 | 4篇 |
2010年 | 16篇 |
2009年 | 23篇 |
2008年 | 11篇 |
2007年 | 7篇 |
2006年 | 3篇 |
2005年 | 2篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2001年 | 5篇 |
1999年 | 6篇 |
1998年 | 15篇 |
1997年 | 8篇 |
1996年 | 14篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 7篇 |
1991年 | 9篇 |
1990年 | 12篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1957年 | 1篇 |
1956年 | 2篇 |
1955年 | 2篇 |
1954年 | 1篇 |
排序方式: 共有260条查询结果,搜索用时 0 毫秒
81.
82.
83.
84.
J. WESLEY WILLIAMS DVM MS DENNIS M. MEAGHER DVM PhD DiplomateACVs JOHN R. PASCOE BVSC PhD WILLIAM J. HORNOF DVM MS DiplomateACVR 《Veterinary surgery : VS》1990,19(2):142-147
Upper airway pressure was measured during maximal exercise in 10 Thoroughbred racehorses with naturally occurring upper airway obstruction. Left laryngeal hemiplegia and arytenoid chondropathy resulted in substantial increases (30-40 cm H2O) in inspiratory upper airway pressure (Pl), whereas complicated aryepiglottic entrapment and subepiglottic cysts produced only modest increases (15 cm H2O) in Pl. Uncomplicated aryepiglottic entrapment and grade IV pharyngeal lymphoid hyperplasia produced only slight increases (3-5 cm H2O). In general, surgical procedures restored airway pressures to within normal limits. Subtotal arytenoidectomy improved but did not normalize airway pressures in horses with arytenoid chondropathy. Pharyngeal lymphoid hyperplasia appeared to have little effect on upper airway function. 相似文献
85.
Hollow viscus perforation and leakage were treated successfully in eight dogs by suturing the surface of a loop of healthy bowel over the leaking areas, forming a serosal patch. The technique also was employed in three dogs and one cat to reinforce areas of potential leakage in the urinary bladder, small intestine, and colon.
Healthy bowel serosa was used to seal perforations in both clean-contaminated and grossly infected visceral wounds. The serosal patch, with its muscular and submucosal reinforcing layers, resisted intraluminal pressure and proved successful in some animals where omental patching or wrapping had failed. 相似文献
Healthy bowel serosa was used to seal perforations in both clean-contaminated and grossly infected visceral wounds. The serosal patch, with its muscular and submucosal reinforcing layers, resisted intraluminal pressure and proved successful in some animals where omental patching or wrapping had failed. 相似文献
86.
This paper presents clinical, radiographic and pathological appearances in a case of pulmonary alveolar lipoproteinosis in a one-year-old Cocker Spaniel. This condition, well recognized in man appears not to have been reported previously as a spontaneous disease in the dog. The main features were insidious decreased exercise tolerance and increasing respiratory embarrassment. Radiographic lung changes were associated with filling of pulmonary alveoli with PAS-positive lipoproteina-ceous material. Inflammatory changes were minimal. The alveolar material consisted of excessive amounts of a substance that resembled surfactant. 相似文献
87.
The Effect of Trans-Stifle External Skeletal Fixation and Hyaluronic Acid Therapy on Articular Cartilage in the Dog 总被引:8,自引:0,他引:8
WILLARD G. KELLER dvm DENNIS N. ARON dvm Dipiomate acvs GEORGE N. ROWLAND DVM PhD STEWART ODEND'HAL dvm PhD JOHN BROWN dvm PhD 《Veterinary surgery : VS》1994,23(2):119-128
Transarticular external skeletal (TES) fixators were applied unilaterally to the stifle joints of 10 young adult dogs. After 4 weeks, the fixators were removed from all dogs. Two dogs were not allowed a remobilization period, whereas 8 dogs were provided with 4 additional weeks of weight-bearing activity in a kennel run. Four dogs were given high-molecular weight hyaluronic acid by intra-articular injection weekly during the remobilization period. Clinical gait evaluations and range of motion were determined during the remobilization period. Articular cartilage samples from both stifle joints of all dogs were evaluated histologically and histochemically. No significant differences in gait scores or range of motion were noted between treated and untreated dogs. Articular cartilage proteoglycan content was reduced after 4 weeks of trans-stifle external skeletal fixation as determined by loss of alcian blue (AB) histochemical staining. Improved homogeneity of histochemical staining was observed after remobilization. However, remobilization was associated with histological damage to the surface and tangential layers of articular cartilage. Remobilization combined with hyaluronic acid (HA) therapy improved histochemical staining and reduced structural damage to articular cartilage when compared with remobilization alone. 相似文献
88.
89.
The effect of nitrogen in spring on shoot number and leaf area of white clover in mixtures 总被引:1,自引:0,他引:1
Swards of perennial ryegrass/white clover were cut to 3 cm in March and allowed to regrow for approximately thirteen weeks. Half the swards received nitrogenous fertilizer at the time of cutting (+N treatment) while the other half received none (—N treatment).
About four weeks after the application of treatments, the number of clover shoots in the — N treatment was significantly higher than that in the +N; at this stage total leaf area index on both treatments was low, but significantly greater in the + N. After 30 days, more light was reaching ground level in the — N treatments, and about 40 days after cutting there was between 17 and 50% more clover in the — N treatment than the +N.
It is suggested that the inhibition of stolon branching with a consequent restriction in the rate of increase of clover leaf area is a major factor in the adverse effect of N fertilizer on clover. 相似文献
About four weeks after the application of treatments, the number of clover shoots in the — N treatment was significantly higher than that in the +N; at this stage total leaf area index on both treatments was low, but significantly greater in the + N. After 30 days, more light was reaching ground level in the — N treatments, and about 40 days after cutting there was between 17 and 50% more clover in the — N treatment than the +N.
It is suggested that the inhibition of stolon branching with a consequent restriction in the rate of increase of clover leaf area is a major factor in the adverse effect of N fertilizer on clover. 相似文献
90.
[目的]定位监测高产膜下滴灌制种玉米田间土壤水分动态变化,为膜下滴灌制种玉米拔节后水分管理提供理论依据.[方法]采用时域反射仪(TDR)对膜下滴灌制种玉米田间土壤水分动态变化连续监测并分析干物质的积累情况,运用水分平衡法计算膜下滴灌制种玉米各生育时期耗水量和水分生产率.[结果]拔节期至灌浆期45d左右是玉米耗水高峰期,日平均耗水强度为6.4 mm;灌浆期日耗水强度为3.2 mm.[结论]制种玉米拔节后根区的土壤体积含水量总是维持在23.5;~31.4;(田间持水量的60;~80;). 相似文献