全文获取类型
| 收费全文 | 79篇 |
| 免费 | 1篇 |
专业分类
| 林业 | 13篇 |
| 农学 | 1篇 |
| 15篇 | |
| 综合类 | 10篇 |
| 农作物 | 1篇 |
| 水产渔业 | 3篇 |
| 畜牧兽医 | 30篇 |
| 植物保护 | 7篇 |
出版年
| 2022年 | 1篇 |
| 2020年 | 1篇 |
| 2018年 | 1篇 |
| 2017年 | 4篇 |
| 2016年 | 4篇 |
| 2015年 | 1篇 |
| 2013年 | 7篇 |
| 2012年 | 2篇 |
| 2011年 | 6篇 |
| 2010年 | 2篇 |
| 2009年 | 2篇 |
| 2008年 | 7篇 |
| 2007年 | 4篇 |
| 2006年 | 10篇 |
| 2005年 | 4篇 |
| 2004年 | 2篇 |
| 2003年 | 7篇 |
| 2002年 | 2篇 |
| 2001年 | 5篇 |
| 2000年 | 2篇 |
| 1997年 | 1篇 |
| 1995年 | 1篇 |
| 1982年 | 1篇 |
| 1960年 | 1篇 |
| 1915年 | 1篇 |
| 1911年 | 1篇 |
排序方式： 共有80条查询结果，搜索用时 15 毫秒
31.
ABSTRACT The effect of weather conditions on the infection of peach shoots by Taphrina deformans was investigated both under orchard conditions and in controlled-environment experiments. Leaf curl incidence and severity were related to rainfall, length of wet periods, and temperature during wetness and during the incubation period, as well as to the development stage of shoots. Surface wetness was more important than rainfall for infection to occur. Minimum rainfall for infection was 3 mm, with a wet period of at least 12.5 h; higher amounts of rainfall did not cause infection when the wet period they triggered was shorter. Wet periods initiated by dew or fog were too short for infection to occur. Infection occurred only when air temperature was <16 degrees C during the wet period and <19 degrees C during incubation. Logistic equations relating relative disease incidence and either duration of wetness or temperature were developed under controlled-environment conditions, with asymptotes at >/=48 h of wetness and 相似文献
32.
33.
Siracusa L Patanè C Avola G Ruberto G 《Journal of agricultural and food chemistry》2012,60(1):309-314
"Long-storage" tomato ( Solanum lycopersicum L.) is a niche product typical of the Mediterranean area, traditionally cultivated under no water supply, the fruits of which combine a good taste with excellent nutritional properties. High-performance liquid chromatography coupled with diode array detection and electron spray-mass spectrometry (HPLC/DAD/ESI-MS) was used to identify the phenolic profile in 10 landraces of long-storage tomato, grown under a typical semiarid climate, as compared to a processing tomato hybrid cultivated in the same environment, under both well-irrigated and unirrigated conditions. Sixteen different secondary metabolites, belonging to the classes of cinnamoylquinic acids and flavonoids, were identified. Quantitative analyses were also performed to monitor the changes in the phenolic content along the batch. The results highlighted that landraces originating from the same area exhibit different fruit morphologies but own a similar biochemical profile. Moreover, the two controls (well irrigated and unirrigated) are placed into the same cluster, suggesting that these secondary metabolites in tomato fruits may be more genetics-dependent than environment-dependent. Given the analysis of phenols nowadays represents a useful tool to assess the genetic variability in tomato, these compounds could be adopted as chemotaxonomic markers in the traceability of this niche product. 相似文献
34.
Neoskrjabinolepis (Neoskrjabinolepidoides) merkushevae sp. n. is described from the shrew Sorex minutus L. (type host) from Belarus. The new species is characterised by rostellar hooks 35-37 microm long, provided with small epiphyseal thickening of the handle; short (35-40 microm) cirrus consisting of a basal part with claw-shaped spines, a parabasal part with thin needle-shaped spines and an unarmed distal part; cirrus-sac slightly passing into median field; and 12-16 eggs per gravid uterus. In addition to the type host and the type locality, the host range of the new species includes Sorex araneus L. and there are geographical records from Bulgaria, Lithuania and North-East Altay (Russia). 相似文献
35.
36.
37.
38.
Giampieri F Alvarez-Suarez JM Tulipani S Gonzàles-Paramàs AM Santos-Buelga C Bompadre S Quiles JL Mezzetti B Battino M 《Journal of agricultural and food chemistry》2012,60(9):2322-2327
Exposure to UV-A radiation is known to induce discrete lesions in DNA and the generation of free radicals that lead to a wide array of skin diseases. Strawberry (Fragaria × ananassa) contains several polyphenols with strong antioxidant and anti-inflammatory activities. Because the major representative components of strawberry are anthocyanins, these may significantly contribute to its properties. To test this hypothesis, methanolic extracts from the Sveva cultivar were analyzed for anthocyanin content and for their ability to protect human dermal fibroblasts against UV-A radiation, as assayed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenytetrazolium bromide and Comet assays. Five anthocyanin pigments were identified using high-performance liquid chromatography-diode array detection-electrospray ionization/mass spectrometry. Moreover, the strawberry extract showed a photoprotective activity in fibroblasts exposed to UV-A radiation, increasing cellular viability, and diminishing DNA damage, as compared to control cells. Overall, our data show that strawberry contains compounds that confer photoprotective activity in human cell lines and may protect skin against the adverse effects of UV-A radiation. 相似文献
39.
Sharptooth catfish, Clarias gariepinus, from the Rietvlei Dam near Pretoria, South Africa were examined for internal platyhelminth parasites. Two adult cestodes, Polyonchobothrium clarias (stomach) (prevalence 71%, mean intensity = 5, n = 7) and Proteocephalus glanduliger (anterior intestine) (prevalence 14%, mean intensity = 2, n = 7), were found in the gut while metacercariae of one larval digenean, Ornithodiplostomum sp. (prevalence 14%, mean intensity = 140, n = 7), were found encysted in the muscles. The morphology of these species, based on light and scanning electron microscopy as well as histological analysis, and how they differ from previously described specimens, are discussed. Ornithodiplostomum is a new record in southern Africa. Infection levels of the host fish were mild compared to records from previous surveys. 相似文献
40.
We evaluated the effects of risk factors and control policies following the highly pathogenic avian influenza (HPAI) epidemic that struck northern Italy's poultry industry in the winter of 1999–2000. The epidemic was caused by a type-A influenza virus of the H7N1 subtype, that originated from a low-pathogenic AI virus which spread among poultry farms in northeastern Italy in 1999 and eventually became virulent by mutation. Most infected premises (IP) were located in the regions of Lombardy and Veneto (382 out of 413, 92.5%), and the eradication measures provided for in the European legislation were enforced. In Veneto, where flock density was highest, infection-control was also accomplished by means of depopulation of susceptible flocks through a ban on restocking and pre-emptive slaughter of flocks that were in the vicinities of or that had dangerous contacts with IPs. In Lombardy, such control measures were applied to a lesser extent. Infection incidence rate (IR) was 2.6 cases per 1000 flocks per day in Lombardy and 1.1 in Veneto. After the implementation of infection-control measures, the at-risk population, the percentage of flocks ≤1.5 km from IPs, and the HPAI-IR underwent a greater reduction in Veneto than in Lombardy. Although the proximity (≤1.5 km) to IPs in the temporal risk window (TRW) was a major risk factor for HPAI at the individual flock level, its effect at the population level (population-attributable fraction) did not exceed 31.3%. Viral transmission therefore also occurred among relatively distant flocks. Turkey flocks were characterised by grerater IR of HPAI compared with other bird species such as layer hens, broilers, gamebirds, and waterfowl, even when located at distances >1.5 km from IPs. In Lombardy, IR for species other than turkeys was also relatively high. 相似文献