全文获取类型
收费全文 | 5047篇 |
免费 | 481篇 |
国内免费 | 1篇 |
专业分类
农学 | 12篇 |
8篇 | |
综合类 | 3篇 |
农作物 | 2篇 |
水产渔业 | 5篇 |
畜牧兽医 | 5496篇 |
植物保护 | 3篇 |
出版年
2024年 | 6篇 |
2023年 | 91篇 |
2020年 | 167篇 |
2019年 | 3篇 |
2018年 | 122篇 |
2017年 | 134篇 |
2016年 | 86篇 |
2015年 | 145篇 |
2014年 | 225篇 |
2013年 | 243篇 |
2012年 | 181篇 |
2011年 | 210篇 |
2010年 | 167篇 |
2009年 | 247篇 |
2008年 | 152篇 |
2007年 | 96篇 |
2006年 | 82篇 |
2005年 | 81篇 |
2004年 | 144篇 |
2003年 | 147篇 |
2002年 | 166篇 |
2001年 | 159篇 |
2000年 | 122篇 |
1999年 | 118篇 |
1998年 | 171篇 |
1997年 | 180篇 |
1996年 | 160篇 |
1995年 | 159篇 |
1994年 | 140篇 |
1993年 | 153篇 |
1992年 | 175篇 |
1991年 | 148篇 |
1990年 | 187篇 |
1989年 | 131篇 |
1988年 | 114篇 |
1987年 | 145篇 |
1986年 | 60篇 |
1985年 | 78篇 |
1984年 | 82篇 |
1983年 | 80篇 |
1982年 | 36篇 |
1981年 | 12篇 |
1980年 | 7篇 |
1977年 | 4篇 |
1974年 | 2篇 |
1961年 | 2篇 |
1960年 | 1篇 |
1958年 | 1篇 |
1956年 | 1篇 |
1947年 | 1篇 |
排序方式: 共有5529条查询结果,搜索用时 78 毫秒
281.
Patrick M. McCue DVM PhD Dirk K. Vanderwall DVM PhD Edward L. Squires PhD 《Journal of Equine Veterinary Science》1997,17(5):267-269
A single mummified fetus was removed from the uterus of a 23-year-old mare that had been bred approximately 30 months previously. The mare had received supplemental progestin therapy for approximately 150 days after ovulation. This case represents the longest recorded occurrence of fetal mummification in the mare. Progestion administration may have contributed to the initial retention of the fetus in the uterus. 相似文献
282.
Andrea J. Fascetti Glenna E. Mauldin DVM MS G. Neal Mauldin 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(1):9-13
There are no available biochemical analyses that will reliably identify malnourished cats or enable monitoring them during supportive alimentation. Studies in people indicate that creatine kinase (CK) activity is high in malnourished patients and may decrease in response to nutritional intervention. The purpose of this study was to determine the value of quantifying serum CK activities in anorectic cats and to assess the usefulness of this test in monitoring nutritional support in these patients. Serum CK activity was evaluated in nonanorectic cats (Group 1, n = 25), and in hospitalized, anorectic cats that received nutritional support through a nasoesophageal tube (Group 2, n = 25). Anorectic cats had a significantly higher serum CK activity (median = 2,529 U/L, range 88 to 153,000 U/L) than the control group (median = 175 U/L, range 81 to 363 U/L, P < .001). There were significant positive correlations between serum CK and both aspartate transaminase (AST) ( P < .05; r = .59) and lactate dehydrogenase (LDH) (P < .05; r = .41) activities. Serum CK activity was significantly lower in anorectic cats after 48 hours of nutritional support than at time 0 ( P < .001) and eventually returned to normal with continued support. Serum CK activity may serve as a useful marker in assessing and monitoring nutritional status in cats. 相似文献
283.
284.
C.J. Hillidge PhD FRCVS T.J. Lane DVM T.W. Whitlock BS 《Journal of Equine Veterinary Science》1985,5(6):351-353
A retrospective survey was carried out at a Florida racetrack in 1984, to determine the prevalence of exercise-induced pulmonary hemorrhage (EIPH) in Appaloosa horses. Of 94 horses examined endoscopically between 30 and 90 minutes after racing, forty-nine (52%) were found to exhibit some degree of EIPH. There was a significantly increased prevalence of EIPH with increasing age in this population. An increased prevalence of EIPH was noted with mares and geldings as compared with stallions, but this was not statistically significant. More horses bled from the right lung than from the left, but the difference was statistically insignificant. An increased prevalence of EIPH with distance run was evident, but this was not significant when animals of the same age were examined. 相似文献
285.
286.
Medial Plating for the Repair of Middle and Distal Diaphyseal Fractures of the Humerus in Dogs 总被引:1,自引:0,他引:1
JOSEPH HARARI ms dvm SIMON C. ROE bvsc mvst ANN L. JOHNSON dvm ms Dipiomateacvs CHARLES W. SMITH dvm ms Dipiomateacvs 《Veterinary surgery : VS》1986,15(1):45-48
Six middle and distal humeral shaft fractures in dogs were repaired by the application of a bone plate along the medial shaft of the humerus. In all animals, clinical and radiographic evidence of normal bone healing was observed. The bone plate and ancillary implants were removed from five dogs by 10 months. In none of the six dogs were any untoward effects of placing the bone plate along the medial shaft of the humerus detected nor were there any difficulties encountered with the medial humeral soft tissues. 相似文献
287.
288.
Comparison of Three Skin Preparation Techniques in the Dog Part 1: Experimental Trial 总被引:1,自引:0,他引:1
DEBORA J. OSUNA DVM DAVID J. DeYOUNG DVM DiplomateACVs RICHARD L. WALKER DVM PhD MPVM 《Veterinary surgery : VS》1990,19(1):14-19
Premeasured, clipped areas of skin on both sides of 30 adult dogs were prepared with povidone-iodine (PI), chlorhexidine gluconate (CG) with a saline rinse, or 4% CG with a 70% isopropyl alcohol rinse. Skin bacteria were quantified with Replicating Organism Detection and Counting (RODAC) plates and cultured for identification before, immediately after, and 1 hour after skin preparation. The percentages of bacterial reduction immediately and at hour 1 and the percentages of negative cultures, cultures with more than five colony-forming units (CFUs), and skin reactions were analyzed by analysis of variance and chi-square. The percentage of reduction in skin bacteria for all techniques was significant and comparable with that reported in humans. There were no significant differences between PI and CG results except that acute contact dermatitis was observed more frequently after skin preparation with PI. The authors conclude that for similar application times, PI and 4% CG rinsed with saline or 70% isopropyl alcohol are equally effective for up to 1 hour in the preoperative skin preparation of dogs. 相似文献
289.
SIMON C. ROE BVSc MVSt ANN L. JOHNSON dvm MS DiplomateACVS JOSEPH HARARI DVM MS 《Veterinary surgery : VS》1985,14(3):247-252
A technique using a third bar and guide clamp was developed to permit reduction and stabilization of distal limb fractures with full pins and two connecting bars, one on each side of the bone. The system uses only single Kirschner clamps. Four distal limb fractures were stabilized using this technique. Closed reduction was used in three dogs to avoid devitalization of fragments and avoid contamination of a closed fracture. The fracture site stability achieved with this configuration allowed early return to weight bearing and rapid bone healing. 相似文献
290.
Stanley P. Kus DVM MS Joe P. Morgan DVM Vet med dr 《Veterinary radiology & ultrasound》1985,26(6):196-202
Through the use of a purebred dog skull collection, specific positioning recommendations were established for radiography for the three skull types. It is suggested that the central ray of the beam be maintained at the following mean angles relative to the hard palate for the rostrodorsal-to-caudoventral oblique projection of the foramen magnum: dolicocephalic, 30° mesaticephalic, 20° and brachycephalic, 10°. It is recommended that the head be axially rotated as follows to radiographically separate the roots of the superior canine teeth: dolicocephalic, 48° mesaticephalic, 43° and brachycephalic, 35°. If only the cheek teeth require evaluation, the head should be rotated as follows: dolicocephalic, 37° mesaticephalic, 34° and brachycephalic, 25°. For evaluation of the inferior cheek teeth, it is recommended that the head be rotated as follows: dolicocephalic, 46° mesaticephalic, 44° and brachycephalic, 28°. It is recommended that radiographs of the temporo-mandibular joint be made with the skull axially rotated 10° and longitudinally obliqued as follows: dolicocephalic, 10° mesaticephalic, 14° and brachycephalic, 27°. Suggestions for open-mouth projections for evaluation of the tympanic bullae are that the central ray maintain the following angles relative to the hard palate: dolicocephalic, 4° mesaticephalic, 9° and brachycephalic, 21°. It is recommended that a caudoventral-rostrodorsal oblique projection of the nasal cavity made at 30° to the hard palate replace the open-mouth ventrodorsal in brachycephalic breeds. 相似文献