全文获取类型
收费全文 | 352篇 |
免费 | 36篇 |
专业分类
林业 | 8篇 |
农学 | 17篇 |
基础科学 | 1篇 |
61篇 | |
综合类 | 59篇 |
农作物 | 52篇 |
水产渔业 | 13篇 |
畜牧兽医 | 164篇 |
园艺 | 4篇 |
植物保护 | 9篇 |
出版年
2023年 | 4篇 |
2021年 | 7篇 |
2020年 | 6篇 |
2019年 | 9篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 5篇 |
2015年 | 7篇 |
2014年 | 6篇 |
2013年 | 14篇 |
2012年 | 12篇 |
2011年 | 16篇 |
2010年 | 7篇 |
2009年 | 3篇 |
2008年 | 3篇 |
2007年 | 21篇 |
2006年 | 10篇 |
2005年 | 9篇 |
2004年 | 14篇 |
2003年 | 14篇 |
2002年 | 15篇 |
2001年 | 11篇 |
2000年 | 9篇 |
1999年 | 7篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 8篇 |
1991年 | 14篇 |
1990年 | 10篇 |
1989年 | 5篇 |
1988年 | 11篇 |
1987年 | 8篇 |
1986年 | 12篇 |
1985年 | 6篇 |
1984年 | 8篇 |
1983年 | 9篇 |
1980年 | 5篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1972年 | 3篇 |
1970年 | 6篇 |
1968年 | 3篇 |
1965年 | 2篇 |
1955年 | 2篇 |
排序方式: 共有388条查询结果,搜索用时 15 毫秒
91.
Lynch JA Maxie MG Key DW Hancey JB 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(2):90-91
Bovine respiratory syncytial virus was recovered from the lung of a six month old calf that died during an outbreak of respiratory disease in a cattle herd in Ontario. Lung tissue removed from the calf at necropsy, performed within two hours of death, was frozen at -70°C prior to virus isolation attempts. Syncytia and intracytoplasmic inclusions were demonstrated both in histological sections of the calf's lung and in stained cell culture preparations infected with the bovine respiratory syncytial virus isolate. Direct fluorescent antibody and virus neutralization tests serologically confirmed the identity of the isolate. 相似文献
92.
93.
94.
95.
Olson CG Liu R Yang AB Lynch DW Arko AJ List RS Veal BW Chang YC Jiang PZ Paulikas AP 《Science (New York, N.Y.)》1989,245(4919):731-733
Detailed studies indicate a superconducting gap in the high-temperature superconductor Bi(2)Sr(2)CaCu(2)O(8). Photoemission measurements with high energy and angle resolution isolate the behavior of a single band as it crosses the Fermi level in both the normal and superconducting states, giving support to the Fermi liquid picture. The magnitude of the gap is 24 millielectron volts. 相似文献
96.
97.
Simultaneous measurements of vertical accretion from artificial soilmarker horizons and soil elevation change from sedimentation-erosion table(SET) plots were used to evaluate the processes related to soil building infringe, basin, and overwash mangrove forests located in a low-energy lagoonwhich receives minor inputs of terrigenous sediments. Vertical accretionmeasures reflect the contribution of surficial sedimentation (sedimentdeposition and surface root growth). Measures of elevation change reflectnot only the contributions of vertical accretion but also those ofsubsurface processes such as compaction, decomposition and shrink-swell. Thetwo measures were used to calculate amounts of shallow subsidence (accretionminus elevation change) in each mangrove forest. The three forest typesrepresent different accretionary environments. The basin forest was locatedbehind a natural berm. Hydroperiod here was controlled primarily by rainfallrather than tidal exchange, although the basin flooded during extreme tidalevents. Soil accretion here occurred primarily by autochthonous organicmatter inputs, and elevation was controlled by accretion and shrink-swell ofthe substrate apparently related to cycles of flooding-drying and/or rootgrowth-decomposition. This hydrologically-restricted forest did notexperience an accretion or elevation deficit relative to sea-level rise. Thetidally dominated fringe and overwash island forests accreted throughmineral sediment inputs bound in place by plant roots. Filamentous turfalgae played an important role in stabilizing loose muds in the fringeforest where erosion was prevalent. Elevation in these high-energyenvironments was controlled not only by accretion but also by erosion and/orshallow subsidence. The rate of shallow subsidence was consistently3–4 mm y–1 in the fringe and overwash island forests butwas negligible in the basin forest. Hence, the vertical development ofmangrove soils was influenced by both surface and subsurface processes andthe processes controlling soil elevation differed among forest types.The mangrove ecosystem at Rookery Bay has remained stable as sea levelhas risen during the past 70 years. Yet, lead-210 accretion data suggest asubstantial accretion deficit has occurred in the past century (accretionwas 10–20 cm < sea-level rise from 1930 to 1990) in the fringe andisland forests at Rookery Bay. In contrast, our measures of elevation changemostly equalled the estimates of sea-level rise and our short term estimatesof vertial accretion exceeded the estimates by the amount of shallowsubsidence. These data suggest that (1) vertical accretion in this system isdriven by local sea-level rise and shallow subsidence, and (2) the mangroveforests are mostly keeping pace with sea-level rise. Thus, the vulnerabilityof this mangrove ecosystem to sea-level rise is best described in terms ofan elevation deficit (elevation change minus sea-level rise) based on annualmeasures rather than an accretion deficit (accretion minus sea-level rise)based on decadal measures. 相似文献
98.
Iliev ID Funari VA Taylor KD Nguyen Q Reyes CN Strom SP Brown J Becker CA Fleshner PR Dubinsky M Rotter JI Wang HL McGovern DP Brown GD Underhill DM 《Science (New York, N.Y.)》2012,336(6086):1314-1317
The intestinal microflora, typically equated with bacteria, influences diseases such as obesity and inflammatory bowel disease. Here, we show that the mammalian gut contains a rich fungal community that interacts with the immune system through the innate immune receptor Dectin-1. Mice lacking Dectin-1 exhibited increased susceptibility to chemically induced colitis, which was the result of altered responses to indigenous fungi. In humans, we identified a polymorphism in the gene for Dectin-1 (CLEC7A) that is strongly linked to a severe form of ulcerative colitis. Together, our findings reveal a eukaryotic fungal community in the gut (the "mycobiome") that coexists with bacteria and substantially expands the repertoire of organisms interacting with the intestinal immune system to influence health and disease. 相似文献
99.
Julie Rosser Sabrina Brounts Don Slone Tim Lynch Michael Livesey Faith Hughes Carol Clark 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(6):643-647
Our objective was to compare survival and complication rates of horses undergoing pelvic flexure enterotomy closure with a TA-90 stapler to those with hand-sewn closure. Medical records of horses undergoing pelvic flexure enterotomy between 2001 and 2008 were reviewed. History, clinical signs, surgical findings, surgical techniques, and post-operative complications were recorded. Long-term outcome was established by telephone questionnaire. Of 84 pelvic flexure enterotomies performed, 70 were stapled and 14 were hand-sewn. Seventy-seven horses survived to discharge (91.7%). There were no significant associations between survival and closure technique (P = 0.69). Follow-up was available for 54 horses; 50 survived long-term (93.0%). No statistical significance was identified between long-term survival and closure method (P = 0.39). Forty horses went on to athletic performance (80.0%). TA-90 stapled closure of pelvic flexure enterotomies is a safe technique resulting in survival and complication rates equivalent to those of hand-sewn closure. 相似文献
100.
Namikawa K Maruo T Honda M Hirata H Lynch J Madarame H 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(1):67-70
Gingival mass lesions developed when cyclosporine was administered for 600 days to a female, 7-year-old, longhaired dachshund diagnosed with intractable immune-mediated hemolytic anemia (IMHA). Histopathology indicated hyperplastic suppurative gingivitis. As the anemia improved, the dosage of cyclosporine A (CsA) was markedly decreased, and the mass lesions decreased in size and disappeared, thus suggesting that the mass lesions were an adverse reaction to CsA. 相似文献