全文获取类型
收费全文 | 125篇 |
免费 | 11篇 |
专业分类
林业 | 1篇 |
11篇 | |
综合类 | 20篇 |
农作物 | 2篇 |
水产渔业 | 2篇 |
畜牧兽医 | 97篇 |
园艺 | 1篇 |
植物保护 | 2篇 |
出版年
2021年 | 2篇 |
2020年 | 3篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 1篇 |
2013年 | 10篇 |
2012年 | 3篇 |
2011年 | 5篇 |
2010年 | 3篇 |
2009年 | 1篇 |
2008年 | 11篇 |
2007年 | 4篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 7篇 |
2003年 | 6篇 |
2002年 | 6篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1969年 | 1篇 |
1967年 | 1篇 |
1949年 | 1篇 |
1941年 | 1篇 |
排序方式: 共有136条查询结果,搜索用时 15 毫秒
111.
Collections of Nicotiana glauca containing from 0.45-1.14 mg anabasine per gram dry weight of plant induced moderate - severe toxic signs in pregnant ewes and teratogenic effects in their offspring when the ewes were given single daily doses of the plant that provided from 1.66 - 3.42 mg anabasine per kg body weight. Toxic signs included excess salivation, irregular gait, wobbling while walking or standing, recumbency and death. Teratogenic effects occurred in offspring from animals fed those doses the 30th - 60th day of gestation. Terata expression included limb defects such as a fixed excessive carpal flexure with or without lateral or medial rotation of fore or rear limbs, lordosis, irregular shaped head or cleft palate. 相似文献
112.
113.
The effects of surgery (ovario-hysterectomy) and anesthesia on phytohemagglutinin-induced lymphocyte blastogenesis were studied in vitro in 12 dogs. Four dogs had depressed lymphocyte blastogenic responses after surgery. This suppression was transient with normal blastogenic responses occurring in cells from all dogs 24 hours after surgery. Seemingly, T-lymphocyte function may be depressed, only transiently, after surgery. 相似文献
114.
E T Lyons S C Tolliver J H Drudge T W Swerczek M W Crowe 《American journal of veterinary research》1985,46(4):921-923
Prevalence of natural infections of the lungworm, Dictyocaulus arnfieldi, was investigated in Kentucky in 5,437 live equids (horses, ponies, and asses) on 91 farms by examination of fecal samples over a 15-month-period from January 28, 1983 to April 19, 1984. For the 91 farms investigated, asses only were examined on 1 farm; for the other 90 farms, examinations were made of horses on all of them, of ponies on 4 farms, and of asses on 9 farms. Larvae of D arnfieldi were found in fecal samples of 112 (2%) of 5,379 horses on the 90 farms of which 38% had greater than or equal to 1 infected animal; none of 19 ponies examined was infected. For 39 asses (donkeys and mules) examined, 21 (54%) were infected; infected asses were present on 80% of the 10 farms on which they were examined. The equids, excluding asses, that were examined and the percentage (in parentheses) infected with D arnfieldi included 4,329 (2%) Thoroughbreds, 684 (2%) Standardbreds, 78 (0%) American Saddle Horses, and 307 (3%) miscellaneous (other breeds or mixed breeds of horses and ponies). Equids were separated into 3 categories relative to previous treatment with ivermectin: A (no treatment), B (treatment), and C (treatment unknown).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
115.
Doige CE Crowe S Farrow CS 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(2):70-73
Necrosis of intramedullary bone and bone marrow elements is reported in the long bones of a dog. Radiographically lesions were evident as an irregular increase in intramedullary density. On gross postmortem examination necrotic tissue appeared as yellow-white deposits on the endosteal surface and in the medullary cavity. Microscopically, necrotic bone had empty lacunae and was often covered by basophilic, woven bone. The cause and pathogenesisof aseptic necrosis of bone are discussed. 相似文献
116.
117.
This paper examines why Western Australia's Integrated Fisheries Management (IFM) policy was adopted, its development, achievements, lessons learned and future directions. Adopted in 2004, IFM aims to achieve and maintain fish resource sustainability through optimal catch share arrangements between competing users. It involves setting an allowable harvest level for each resource, using an independent allocation committee process to allocate explicit catch shares for commercial, recreational and customary sectors, and monitoring sectoral catch. IFM provides guidance for managing each sector within its catch share, providing access to that share, and developing reallocation mechanisms to transfer sectoral catch shares. The three most important multi‐sector resources, western rock lobster, Panulirus cygnus George, metropolitan Roe's abalone, Haliotis roei Grey, and west coast demersal scalefish, have undergone the allocation process. The first two are operational while the third is almost complete. Allocation outcomes demonstrate the need to account for each sector's catch, with credible scientific data to underpin decision‐making, independent transparent allocation processes, robust sectoral representation, workable reallocation mechanisms and management arrangements to ensure that all sectors can access their allocated share. IFM generates fair decisions for optimal resource use to reduce intersectoral conflict and provide better community outcomes, with wide applicability across other jurisdictions. 相似文献
118.
N. Ochiai M. L. Powelson F. J. Crowe R. P. Dick 《Biology and Fertility of Soils》2008,44(8):1013-1023
Verticillium dahliae is a major, persistent pathogen in soil but conventional control is becoming more difficult because of increasing costs and
environmental impacts of pesticides. Organic amendments can naturally suppress plant diseases, but to be reliable, mechanisms
and suppressive soil indicators need to be understood. Consequently, a 3 × 3 factorial experiment was conducted in two separate
fields over 2 years with three green manure types (Austrian winter pea, Pisum sativum L.; broccoli Brassica oleracea L.; or Sudan grass, Sorghum vulgare), incorporated at three rates (6, 12, or 24 Mg ha−1 dry biomass). The relationship between soil chemical and microbiological properties and suppression of Verticillium wilt
of potato was investigated using correlation and stepwise multiple-linear-regression (MLR) analysis. V. dahliae inoculum density (ID) were positively correlated with relative area under the senescence progress curve (RAUSPC) in both
2002 and 2003. In 2002, in addition to ID, low soil pH, low Ca, high K, high Mg, high total soil C, and low arylsulfatase
activity were associated with low RAUSPC. Soil pH, Ca, K, and Mg were not impacted by green manure treatments, but rather
indicated a pre-existing soil gradient at the 2002 site. In 2003, in addition to ID, high values of NO3
−−N, total C, fluorescein diacetate hydrolysis (FDA), microbial respiration, and microbial biomass C were associated with low
RAUSPC. These six factors were affected by green manure treatments. The best MLR model included terms for ID, FDA, and soil
pH, and accounted for 70% of the variability in RAUSPC. 相似文献
119.
Nation PN Crowe SP Harries WN 《The Canadian veterinary journal. La revue veterinaire canadienne》1982,23(11):323-326
The clinical signs and postmortem findings in sheep from two flocks accidentally poisoned with monensin are described. Clinical signs began within 24 hours of exposure to monensin. In the acute stages they consisted of lethargy, stiffness, muscular weakness, a stilted gait and recumbency. Feed refusal was seen in one flock but not in the second. Subacute to chronic clinical signs were decreased muscle volume of the rump and thigh. When forced to run, chronically affected sheep had a stilted, stiff legged, rocking horse gait.
Gross postmortem changes were not always visible. Where visible, they affected skeletal muscles and consisted of pale streaking, with atrophy in the chronic stages. Lesions were most severe in muscles of the rump and hind limbs. Microscopically myofiber swelling and hyalinization were seen with interstitial mononuclear cell reaction and extensive sarcoplasmic mineralization in some cases. Chronic lesions consisted of fibrosis and myofiber atrophy. In lambs less than one month old, diffuse gastrointestinal hemorrhage was the only finding.
相似文献120.
Effectiveness of an experimental consensus phytase in improving dietary phytate-phosphorus utilization by weanling pigs 总被引:3,自引:0,他引:3
Consensus phytase is a new biosynthetic, heat-stable enzyme derived from the sequences of multiple homologous phytases. Two experiments were conducted to determine its effectiveness, relative to inorganic P and a mutant enzyme of Escherichia coli phytase (Mutant-EP), in improving dietary phytate-P availability to pigs. In Exp. 1, 36 pigs (3 wk old, 7.00 +/- 0.24 kg of BW) were fed a low-P corn-soybean meal basal diet plus consensus phytase at 0, 250, 500, 750, 1,000, or 1,250 U/kg of feed for 5 wk. Plasma inorganic P concentration, plasma alkaline phosphatase activity, bone strength, and overall ADG and gain:feed ratio of pigs were improved (P < 0.05) by consensus phytase in both linear (R2 = 0.20 to 0.70) and quadratic (R2 = 0.30 to 0.70) dose-dependent fashions. In Exp. 2, 36 pigs (4 wk old, 9.61 +/- 0.52 kg BW) were fed the basal diet + inorganic P at 0.1 or 0.2%, consensus phytase at 750 or 450 U/kg of feed, Mutant-EP at 450 U/kg of feed, or 225 U consensus + 225 U Mutant-EP/kg of feed. Pigs fed 750 U of consensus phytase or 450 U of Mutant-EP/kg feed had plasma inorganic concentrations and bone strength that fell between those of pigs fed 0.1 or 0.2% inorganic P. These two measures were 16 to 29% lower (P < 0.05) in pigs fed 450 U of consensus phytase/kg of feed than those of pigs fed 0.2% inorganic P. Plasma inorganic P concentrations were 14 to 29% higher (P < 0.05) in pigs fed Mutant-EP vs. consensus phytase at 450 U/kg at wk 2 and 3. In conclusion, the experimental consensus phytase effectively releases phytate P from the corn-soy diet for weanling pigs. The inorganic P equivalent of 750 U of consensus phytase/kg of feed may fall between 0.1 and 0.2%, but this requires further determination. 相似文献