全文获取类型
收费全文 | 382篇 |
免费 | 27篇 |
国内免费 | 2篇 |
专业分类
林业 | 1篇 |
4篇 | |
综合类 | 28篇 |
农作物 | 4篇 |
水产渔业 | 9篇 |
畜牧兽医 | 362篇 |
园艺 | 1篇 |
植物保护 | 2篇 |
出版年
2021年 | 1篇 |
2020年 | 5篇 |
2019年 | 3篇 |
2018年 | 12篇 |
2017年 | 5篇 |
2016年 | 11篇 |
2015年 | 12篇 |
2014年 | 12篇 |
2013年 | 39篇 |
2012年 | 12篇 |
2011年 | 7篇 |
2010年 | 24篇 |
2009年 | 21篇 |
2008年 | 16篇 |
2007年 | 12篇 |
2006年 | 11篇 |
2005年 | 6篇 |
2004年 | 4篇 |
2003年 | 10篇 |
2002年 | 15篇 |
2001年 | 8篇 |
2000年 | 5篇 |
1999年 | 8篇 |
1998年 | 16篇 |
1997年 | 11篇 |
1996年 | 11篇 |
1995年 | 6篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 8篇 |
1991年 | 10篇 |
1990年 | 10篇 |
1989年 | 9篇 |
1988年 | 12篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1979年 | 3篇 |
1976年 | 1篇 |
1975年 | 3篇 |
1974年 | 6篇 |
1972年 | 3篇 |
1971年 | 1篇 |
1970年 | 2篇 |
1968年 | 1篇 |
1959年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有411条查询结果,搜索用时 15 毫秒
131.
Because the reproductive performance of mares is lower than that of any other domesticated species, hormone therapy is important in ensuring fertility and proper management of pregnancy. Current techniques of hormone therapy are discussed. 相似文献
132.
Viability of stored equine embryos 总被引:1,自引:0,他引:1
Equine embryos were recovered nonsurgically 6.5 d after ovulation (Exp. 1) and those greater than 200 microns were stored in one of three media: 1) Ham's F10 + 10% fetal calf serum (FCS) under 5% CO2, 5% O2 and 90% N2 at 24 C (Ham's F10); 2) Minimal Essential Medium with Hank's balanced salts + 10% FCS in air (MEM) at 24 C or 3) MEM at 5 C n = 10/treatment). Embryos less than or equal to 200 micron (n = 10) were bisected microsurgically; one-half of each embryo was stored in Ham's F10 and the other half in either Dulbecco's phosphate-buffered saline + 10% FCS in air at 24 C (DPBS), or MEM in air at 24 C. At 0, 12 and 24 h, embryos were: 1) measured; 2) assigned a developmental score of 1 to 4 (1 = tight morula, 4 = expanding blastocyst) and 3) assigned a quality score of 1 to 5 (1 = excellent, 5 = degenerate). Whole embryos stored in MEM at 5 C or 24 C did not (P greater than .05) advance in development by 24 h, whereas those stored in Ham's F10 at 24 C were more (P less than .05) advanced (i.e., higher developmental score) by 24 h. From 0 to 24 h, 1 of 10, 6 of 10 and 7 of 10 whole embryos developed when stored in MEM 5 C, MEM 24 C and Ham's F10 24 C, respectively. Embryo quality was better at 24 h (P less than .05) for embryos stored in Ham's F10 at 24 C compared with MEM at 5 C.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
133.
Histological examination was performed on the cervical spinal cord from 13 horses with chronic cervical compressive myelopathy of 4 to 29 months duration. Structural alterations were correlated with clinical features. At the level of compression, the spinal cord was grossly deformed. Histological alterations included nerve fibre swelling and degeneration, occasional spheroids, astrocytic gliosis, increased macrophage activity and increased perivascular collagen. Myelin degeneration or loss at the level of the compressive lesion was greatest in the ventral and lateral funiculi and less consistently present in the dorsal funiculi. Asymmetry of lesions in the dorsal funiculi was associated with asymmetry of clinical signs in 5 horses. Histological alterations in areas of Wallerian degeneration were similar to that at the level of spinal cord compression, except that perivascular collagen was not increased. Wallerian degeneration was present cranial to the compressed site in the superficial portions of the lateral funiculi and in the middle of the dorsal funiculi. Caudal to the compressed site it was present in the ventral funiculi adjacent to the ventral median fissure and in the middle of the lateral funiculi. Deformation of the spinal cord did not correlate with the severity or duration of clinical signs but was positively correlated with the amount of perivascular collagen increase. The amount of nerve fibre swelling was not correlated with the severity of clinical signs but was negatively correlated with their duration. A rapid loss of nerve fibres apparently occurred early in the course of compression, since there was a marked decrease in the amount of nerve fibre swelling and Marchi stained degenerating myelin with increasing clinical duration.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
134.
135.
136.
137.
138.
Bos AS Brisson BA Holmberg DL Nykamp SG 《Journal of the American Veterinary Medical Association》2007,230(12):1860-1865
OBJECTIVE: To determine whether the ventrodorsal myelographic view can be used to accurately predict the circumferential location of extruded disk material in dogs with thoracolumbar intervertebral disk extrusion (IVDE) and to describe paradoxical contrast obstruction (PCO). DESIGN: Retrospective case series. ANIMALS:104 dogs with Hansen type I IVDE. Procedures-Ventrodorsal myelographic views were reviewed, and contrast patterns were categorized according to 8 predetermined patterns. Agreement among observers was compared, and the predicted location of extruded disk material was compared with surgical findings. RESULTS: Agreement regarding myelographic pattern and location of extruded disk material was moderate (kappa = 0.74 and 0.80, respectively) among the 4 observers. Ninety-three (89%) dogs had myelographic evidence of lateralized extrusion, and in 83 of the 93 (89%), predicted location of extruded disk material matched the surgically confirmed location. In 33 of the 40 (83%) dogs with bilateral contrast column gaps of unequal length, disk material was found to be located on the side with the shorter, rather than the longer, contrast gap, a phenomenon described as PCO. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that the ventrodorsal myelographic view could be used to predict the circumferential location of extruded disk material in dogs with thoracolumbar IVDE more often than previously reported. The PCO phenomenon may be useful in determining the side of lateralization when contrast material does not outline the extruded disk material. 相似文献
139.
Distribution Pattern(s) of Sperm Protein at 22 kDa (SP22) on Fresh,Cooled and Frozen/Thawed Equine Spermatozoa and Expression of SP22 in Tissues from the Testes and Epididymides of Normal Stallions 下载免费PDF全文
LMJ Miller EM Woodward JR Campos EL Squires MHT Troedsson 《Reproduction in domestic animals》2015,50(2):275-282
140.
CASE HISTORY: Eight mohua, or yellowheads (Mohoua ochrocephala), were held in a large open aviary over the summer months of 2003–2004, following their capture for captivebreeding purposes. Two birds died of transportation trauma shortly after arrival, one became ill and died a month later, and another four died within a 2-week period in February 2004. The eighth bird also became ill at this time but survived for a year following treatment with chloroquine and doxycycline. CLINICAL AND PATHOLOGICAL FINDINGS: The affected birds were depressed, lethargic and dyspnoeic. Necropsy of three birds showed a slightly pale and swollen liver and spleen. Impression smears of the liver of one bird revealed schizonts resembling Plasmodium spp. within the cytoplasm of many hepatocytes, which was confirmed histopathologically. Similar protozoal organisms were seen within splenic histiocytes and pulmonary endothelial cells of 5/6 birds. Electron microscopy identified these as protozoal schizonts containing merozoites of similar size and structure to those of Plasmodium spp. DIAGNOSIS: The birds were infected with a protozoal haemoparasite resembling Plasmodium spp.; asexual stages within hepatocytes and endothelial cells of the lung and spleen were typical of this organism. CONCLUSIONS AND CLINICAL RELEVANCE: The mohua captured from west Otago were highly susceptible to avian malaria as they came from an isolated population that was likely to be naïve and have had no previous contact with this organism. The birds were probably infected by bites from mosquitoes feeding off local populations of blackbirds subsequently found to be infected with Plasmodium spp. 相似文献