全文获取类型
收费全文 | 330篇 |
免费 | 21篇 |
专业分类
林业 | 19篇 |
农学 | 7篇 |
95篇 | |
综合类 | 17篇 |
农作物 | 27篇 |
水产渔业 | 31篇 |
畜牧兽医 | 121篇 |
园艺 | 7篇 |
植物保护 | 27篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 10篇 |
2020年 | 9篇 |
2019年 | 8篇 |
2018年 | 11篇 |
2017年 | 10篇 |
2016年 | 13篇 |
2015年 | 5篇 |
2014年 | 9篇 |
2013年 | 9篇 |
2012年 | 21篇 |
2011年 | 30篇 |
2010年 | 22篇 |
2009年 | 20篇 |
2008年 | 29篇 |
2007年 | 23篇 |
2006年 | 25篇 |
2005年 | 18篇 |
2004年 | 18篇 |
2003年 | 18篇 |
2002年 | 13篇 |
2001年 | 1篇 |
2000年 | 5篇 |
1999年 | 1篇 |
1997年 | 3篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1987年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有351条查询结果,搜索用时 15 毫秒
61.
62.
Loredana Zilli Roberta Schiavone Carlo Storelli Sebastiano Vilella 《International Aquatic Research》2012,4(1):1-11
River Gomti, a tributary of river Ganga in northern India, is being polluted due to indiscriminate disposal of domestic sewage and industrial wastes that contain genotoxic chemicals. The study was conducted to evaluate the genotoxic potential of polluted water of river Gomti in two fish species, namely Channa punctatus and Mystus vittatus. The fishes were exposed in situ in nylon cages to the polluted water of river Gomti fixed near a distillery outlet located in Lucknow. The induction of DNA damage and micronuclei were determined in blood erythrocytes using comet assay and micronucleus test, respectively. The induction in micronuclei frequencies and DNA damage were found to be significantly elevated (p?<?0.01) in exposed specimens after 3?days post-exposure as compared to the control, i.e. from laboratory-acclimatized fish specimens. The comparison of DNA damage between the two species indicated that C. punctatus is more sensitive to aquatic pollutants. Thus, this fish could be used as a bio-indicator of genotoxicity for bio-monitoring of water bodies. The results further revealed that the river Gomti is being contaminated with potential genotoxic and mutagenic chemicals produced from industrial and domestic activities; therefore, immediate measures are needed to reduce the inflow of pollutants in the river. 相似文献
63.
Carlo Carli Elisa Mihovilovich Firuz Yuldashev Durbek Khalikov Mohinder S. Kadian 《Potato Research》2010,53(4):313-323
In potato breeding and selection, storability should be regarded as equally important as yield, disease resistance, and quality.
A study documenting the dormancy period, sprouting behavior, and weight loss of 17 International Potato Center potato elite
and advanced clones was carried out in Tashkent, Uzbekistan, under cellar and cold store conditions, during 2008 and 2009.
Ninety tubers of each of 17 clones were allocated to experimental units of 30 tubers each placed in trays and randomized in
three replications following a random complete block design. Therefore, there were three replications of 30 seed tubers each
per entry. The dormancy period ranged from 77 to 115 days and from 100 to 186 days under cellar and cold storage, respectively.
There was a relatively high positive correlation (0.69) for dormancy period between storage systems, indicating that clones
demonstrating longer and shorter dormancy periods under one system will also behave similarly under the other system. A negative
correlation (−0.53 and −0.88) was found between dormancy period and length of the longest sprout in cellar and cold store,
respectively, meaning that clones with shorter dormancy often showed a greater length of their longest sprout. The weight
loss percentage per tuber was similar in both storage systems, from 5.0% to 8.0% in the cellar and from 5.0% to 9.8% in the
cold store, although for different storage periods (an average of 110 and 166 days under cellar and cold storage conditions,
respectively). The study indicated that under cellar conditions, clones with a longer dormancy period and slower rate of sprout
growth have less weight loss during storage and therefore better keeping quality. 相似文献
64.
尽管已取得了良好的遗传进展,并拥有较好的种群管理技术,但母火鸡的抱窝行为仍时常发生。特别是在炎热气候条件下,母火鸡的抱窝现象更甚。目前,预防仍是减少抱窝行为发生的关键。这不仅包括早期检测,而且还包括使母火鸡尽快恢复产蛋的一些实用措施。 相似文献
65.
66.
Carlo Andreotti Daniela Ravaglia Guglielmo Costa 《The Journal of Horticultural Science and Biotechnology》2013,88(6):145-149
SummaryThis research was conducted under the framework of the ISAFRUIT Project and aimed to investigate the effects of different light micro-environments on the final overall quality of nectarine fruit production. Experiments were conducted in a commercial orchard of the nectarine (Prunus persica) ‘Stark Red Gold’ during 2006 and 2007. Reflective mulches were laid down in the inter-row spaces in mid-May. Those environmental conditions affected by mulching such as temperature and reflected light were monitored until fruit harvest. Fruit production per tree was enhanced by mulch-treatment in both years, but the differences were statistically significant only in 2006, when the average fruit weight was also enhanced. Nectarines became more ripe in the 2006 season, whereas no differences in the main fruit quality indices were detected in 2007.The concentrations of phenolic compounds in ripe nectarines were positively enhanced in both years. The increase in concentration of overall phenolic compounds (in mg 100 g?1 fresh weight) was calculated to be approx. 60% in 2006 and 2007, indicating an interesting improvement of the nutraceutical and anti-oxidant potential of nectarines. Experiments were also conducted using UV plus white light irradiation under controlled conditions. The accumulation of phenolic compounds, specifically anthocyanin concentrations, in nectarines previously screened using paper bags were determined at different times after irradiation. The results clearly indicated an inducing effect of UV plus white light irradiation on the synthesis and accumulation of anthocyanins in fruit skin. The consequences for the colour and health potential of nectarines are discussed. 相似文献
67.
68.
Zewei?Miao Laura?Padovani Carlo?Riparbelli Amy?M.?Ritter Marco?Trevisan Ettore?CapriEmail author 《Paddy and Water Environment》2003,1(3):121-132
Pesticides are very important in European rice production. For appropriate environmental protection, it is useful to predict the potential impact of pesticides after application, in paddy fields, in paddy runoff, and in the surrounding water, by calculating predicted environmental concentrations (PECs). In this paper, a joint simulation is described, coupling a field-scale pesticide fate model (RICEWQ) and a transportation model (RIVWQ) to evaluate the potential for predicting environmental concentrations of pesticides in the paddy field and adjacent surface water bodies and comparing the predicted values with the monitoring data. The results demonstrate that the application of the calibrated field-scale RICEWQ model is a conservative method to predict the PEC at the watershed level, overestimating the observed data; the coupled RICEWQ and RIVWQ models could be adequately used to predict PECs in the surrounding water at watershed level and in the higher tier risk assessment procedure. 相似文献
69.
70.