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181.
Characterization of widespread canine leishmaniasis among wild carnivores from Spain 总被引:1,自引:0,他引:1
Sobrino R Ferroglio E Oleaga A Romano A Millan J Revilla M Arnal MC Trisciuoglio A Gortázar C 《Veterinary parasitology》2008,155(3-4):198-203
Visceral Leishmaniasis (VL) is an emerging zoonotic parasitic disease caused by Leishmania infantum in Mediterranean countries, with sand flies (Phlebotomus spp.) as vectors and dogs as the main domestic reservoir. The role of wild carnivores in the epidemiology of leishmaniasis is still controversial. In order to determine the prevalence of natural infection with L. infantum in wild carnivores from Spain, we analyzed 217 samples by PCR and western blotting and used restriction fragment length polymorphism (RFLP) to compare the patterns present in wild carnivores with those of domestic dogs from the same areas. DNA of the parasite was detected in spleen or blood samples from 35 (16.12%) analyzed wild carnivores, including 8 of 39 (20.5%) wolves (Canis lupus), 23 of 162 (14.1%) foxes (Vulpes vulpes), 2 of 7 (28.6%) Egyptian mongooses (Herpestes ichneumon), 1 of 4 genets (Geneta geneta), and 1 of 4 Iberian lynxes (Lynx pardinus). No significant sex or age differences in prevalence were observed in wolves and foxes (P>0.05), but there was a significant difference among regions in foxes (P<0.05). A total of 12 PCR-RFLP patterns were found in foxes, 6 in wolves, 4 in dogs, 2 in Egyptian mongooses and 1 in lynx and genet. RFLP patterns differed between dogs and foxes in the two areas where they could be compared. This is the first study of canine leishmaniasis in wild canids and other carnivores from different regions of Spain by PCR. The prevalence of infection indicates the existence of natural infection in apparently healthy wild carnivore populations, and our results are suggestive of a sylvatic cycle independent of dogs. 相似文献
182.
Simulating the spread of classical swine fever virus between a hypothetical wild-boar population and domestic pig herds in Denmark 总被引:1,自引:1,他引:0
Denmark has no free-range wild-boar population. However, Danish wildlife organizations have suggested that wild boar should be reintroduced into the wild to broaden national biodiversity. Danish pig farmers fear that this would lead to a higher risk of introduction of classical swine fever virus (CSFV), which could have enormous consequences in terms of loss of pork exports. We conducted a risk assessment to address the additional risk of introducing and spreading CSFV due to the reintroduction of wild boar. In this paper, we present the part of the risk assessment that deals with the spread of CSFV between the hypothetical wild-boar population and the domestic population. Furthermore, the economic impact is assessed taking the perspective of the Danish national budget and the Danish pig industry. We used InterSpreadPlus to model the differential classical swine fever (CSF) risk due to wild boar. Nine scenarios were run to elucidate the effect of: (a) presence of wild boar (yes/no), (b) locations for the index case (domestic pig herd/wild-boar group), (c) type of control strategy for wild boar (hunting/vaccination) and (d) presence of free-range domestic pigs. The presence of free-range wild boar was simulated in two large forests using data from wildlife studies and Danish habitat data. For each scenario, we estimated (1) the control costs borne by the veterinary authorities, (2) the control-related costs to farmers and (3) the loss of exports associated with an epidemic. Our simulations predict that CSFV will be transmitted from the domestic pig population to wild boar if the infected domestic pig herd is located close to an area with wild boar (<5 km). If an outbreak begins in the wild-boar population, the epidemic will last longer and will occasionally lead to several epidemics because of periodic transfer of virus from groups of infected wild boar to domestic pig herds. The size and duration of the epidemic will be reduced if there are no free-range domestic pig herds in the area with CSF-infected wild boar. The economic calculations showed that the total national costs for Denmark (i.e. the direct costs to the national budget and the costs to the pig industry) related to an outbreak of CSF in Denmark will be highly driven by the reactions of the export markets and in particular of the non-EU markets. Unfortunately, there is a substantial amount of uncertainty surrounding this issue. If hunting is used as a control measure, the average expenses related to a CSF outbreak will be 40% higher if wild boar are present compared with not present. However, a vaccination strategy for wild boar will double the total costs compared with a hunting strategy. 相似文献
183.
M. Zeinalabedini K. Majourhat M. Khayam-Nekoui V. Grigorian M. Torchi F. Dicenta P. Martínez-Gómez 《Scientia Horticulturae》2008
In this study, the genetic diversity of four Iranian wild Prunus species including Prunus eleagnifolia, Prunus hauskenchtii, Prunus scoparia and Prunus lycioides were investigated using morphological, protein and DNA markers. DNA markers included nuclear and chloroplast SSRs and self-incompatibility (S) allele amplification. At the morphological level, leaf width showed significant differences between the four wild Prunus species. Concerning fruit and kernel characters, their values are relatively similar indicating the high degree of homoplasy described in Prunus. Nuclear SSR markers have been the most abundant markers with a higher polymorphism in comparison with morphological, protein and chloroplast SSR markers. Results also indicated the high variability present in the S locus. On the other hand, the correlation between the clustering based on DNA markers and protein were in general low. Dendogram performed using nuclear and chloroplast SSR indicated a more diffuse clustering between the wild almond species probably due to the natural introgression of genes observed in these wild almond species. Data from the analysis of the total protein seems to be more accurate to establish taxonomy relationships in these very close wild species. 相似文献
185.
我国三个野生稻种谷粒和花药形态的扫描电镜观察 总被引:19,自引:2,他引:17
为了探求栽培稻同野生稻的亲缘关系,采用扫描电镜比较观嘉了我国的普通野稻(O. rufipogon)、药用野稻(O. officinalis)、瘤粒野稻(O. meyeriana subsp. tuberculata)和栽培稻(0.sativa)的谷粒和花药的形态结构,获得下列主要结果:1)谷粒表面的形态特征——栽培稻,普通野稻和药用野稻是由排列整齐、分布均匀的乳头状突起组成,瘤粒野稻是由分布不均匀的小瘤状突起组成。栽培稻、普通野稻和药用野稻具有粗刺毛和纤细毛,瘤粒野稻具有钩毛和纤细毛。2)花药壁表面结构——栽培稻和普通野稻是由排列整齐的长形细胞组成;药用野稻和瘤粒野稻由两类细胞组成,一类是排列整齐的细胞, 另一类是大小不均、排列不呈条状的细胞。从谷粒形态、刺毛种类和分布、稃表面结构、花药形态、花药壁表面结构的相似性和差异性的研究结果表明,栽培稻与普通野稻的亲缘关系较近。 相似文献
186.
Cutting and resprouting of Detarium microcarpum and herbaceous forage availability in a semiarid environment in Burkina Faso 总被引:1,自引:0,他引:1
The tree-shrub savanna ‘Forêt Classée de Nazinon’ (Burkina Faso) is submitted to a management of grazing and rotational cutting
of Detarium microcarpum. This species resprouts after cutting. In order to investigate whether this silvopastoral land use
system is sustainable, aboveground herbaceous biomass was measured on subplots under uncut trees (‘uncut’), next to the stubs
of cut trees (‘cut’) and on subplots not influenced by the (former) crowns of trees (‘open grassland’) in four lots. These
lots were cut one, three, six and seven years before the study. Vegetation composition of the lots and the composition of
the diet of cattle were also determined. Comparisons were made between treatments and lots. Herbaceous biomass was lower in
the open grassland subplots than in uncut or cut subplots. We speculate that soil enrichment and more efficient precipitation
input in (former) tree crown zones could have resulted in this pattern. Cutting and subsequent resprouting of trees did not
lead to significant differences in herbaceous biomass between cut and uncut subplots. The most simple explanation for this
is that the trees could extend their roots beyond the location of their neighbouring trees. Biomass and coverage of perennial
grasses, mainly Andropogon ascinodis and Andropogon gayanus, did not change in lots cut one, three or six years before the
study, but decreased dramatically in lots that were cut seven years before the study. When foraging, cattle spent more than
90% of their time feeding on these species. This indicates that, as a consequence of tree cutting, forage availability may
be reduced to the point where local herdsmen are forced to take their cattle to another region.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
188.
189.
采用地锦草水煎提取物和水醇提取物分别制备地锦片和地锦注射液并作相关质量检查,结果表明:地锦草粉,水煎浸膏,淀粉以1:2:2的比例所制的地锦片崩解时限为4min,10片均重3.05g麻面率在2%以下,片子表面有小花斑;地锦草注射液的局部刺激指数〈1.4级,试验兔体温升高值〈0.5℃,3只体温升高总和为1.1℃,溶血试验,蛋白质和鞣质检查均为阴性。 相似文献
190.
采用聚丙烯酰胺不连续凝胶垂直电泳技术对三疣梭子蟹Portunus trituberbuculatus4个野生群体(鸭绿江口、莱州湾、海州湾和舟山)的同工酶进行检测,分析群体间的生化遗传差异.结果发现(1) 4个群体的多态座位百分数(P0.99)分别为:鸭绿江口13.6%、莱州湾13.6%、海州湾13.6%和舟山13.6%.(2) 4个群体间的生化遗传差异不显著,4个群体间的遗传距离D=0.000 54~0.001 70,属种内群体间差异.(3)聚类分析表明:4个群体分为两组,海州湾和舟山两群体之间的亲缘关系最近,聚为一组.莱州湾和鸭绿江口群体亲缘关系比较近,聚为另一组. 相似文献