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41.
Kido N Wada Y Takahashi M Kamegaya C Omiya T Yamamoto Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(6):845-847
The prevalence of Dirofilaria immitis in free-ranging raccoon dogs (Nyctereutes procyonoides viverrinus) was examined in the southeast region of Kanagawa Prefecture, Japan, using a rapid immunomigration (RIM) test kit. Between April 2007 and March 2010, we examined 108 raccoon dogs rescued and housed by the Kanazawa Zoological Garden. D. immitis infection was found in 8 (7.4%) raccoon dogs. This is the first report to reveal the prevalence of D. immitis infection in living raccoon dogs. The prevalence of the infection was lower than previously reported values obtained on postmortem examination. One reason might be that the present study included young raccoon dogs infected with immature worms. Significant high-risk areas of D. immitis infection in the raccoon dogs were not observed. 相似文献
42.
International Aquatic Research - Rocky intertidal zones are biologically diverse environments with numerous physical stressors; as such, close associations between organisms often develop to... 相似文献
43.
Hydroacoustic data from the eastern equatorial Pacific reveal low-magnitude seismicity concentrated at the propagating tip of the Galapagos Rise in Hess Deep. The patterns of seismicity and faulting are similar to those observed in the process zone of laboratory-scale propagating tensile cracks. Because the fracture energy required for propagation scales with crack length and process zone size, it follows that ridges can propagate stably in the brittle crust without exceptional resisting forces as proposed by previous models based on linear elastic fracture mechanics. 相似文献
44.
The presence or absence of the staygreen trait was screened for 3 consecutive years in 963 wheat lines from various sources, including Indian and CIMMYT germplasm. Staygreen was assessed at the late dough stage by visual scoring (0–9 scale) and the leaf area under greenness (LAUG) measurement. Around 5.5 % of the lines were staygreen, 10.5 % were moderately staygreen, and the remaining lines showed little or no expression of the trait. One hundred lines showing diversity for the staygreen trait were sown under three different sowing dates (timely, late and very late) for 3 consecutive years in three replications to determine the association of staygreen with heat tolerance. There was a decline in yield, biomass, grain filling duration (GFD) and 1,000 grain weight (TGW) under late and very late sowing conditions owing to terminal stress at anthesis and later stages. However, the decline was relatively less in staygreen genotypes compared to the non-staygreen (NSG) ones. The correlation study showed that LAUG and canopy temperature depression (CTD) were strongly correlated. LAUG and CTD were also significantly associated with grain yield, GFD and biomass. To further confirm the association of the staygreen trait with terminal heat stress, individual F2-derived F7 progenies from the cross of the ‘staygreen’ lines with NSG were evaluated for yield and yield traits at the three sowing dates. In each cross, the staygreen progenies showed a significantly smaller decline in yield and TGW under heat stress than the NSG progenies. These results appear to suggest an association between the staygreen trait and terminal heat stress and, thereby, that the staygreen trait could be used as a morphological marker in wheat to screen for heat tolerance. 相似文献
45.
Bishnu Hari Pandit Ramji Prasad Neupane Bishal K. Sitaula Roshan M. Bajracharya 《Small-Scale Forestry》2013,12(3):475-487
In view of the heavy people’s dependence (80 %) on various forms of land-based resources, carbon sequestration should not only be targeted in forests, but also on private land agroforestry. A survey was conducted in 2011 to investigate the gap in contribution of agroforestry carbon to the household economy in the middle hills region of Rasuwa district of Nepal. A total of 120 households were randomly selected and surveyed, of which eight were further examined for detailed tree carbon measurement. It is estimated that a total of 48.60 ton C per hectare has been stocked in agroforestry sites in the middle hills region. Assuming a carbon price of $US12/ton, the total potential income from carbon sequestration per household would amount to NPR 45,490/ha in 20 years of agroforestry if a payment scheme were introduced. The income from carbon sequestration is quite low compared with other agroforestry income. Policy implications are thus oriented towards farmers reaping multiple benefits from the existing international mechanisms by having negotiations based on contribution of all agroforestry components (farm trees, crops and animals) rather than limited to forest carbon stock. To benefit from these multiple functions of farms and forests, the policy framework to address the climate-related affects and risks (e.g., of landslides, burst of Himalayan lakes) should be broad enough to produce potential synergy between the negative effect of climate change and agroforestry income. 相似文献
46.
Maya OI Keisuke YAMADA Hiroyuki HAYAKAWA Hiroshi SUZUKI 《The Journal of reproduction and development》2013,59(1):92-96
Effective preselection of sex has been accomplished in several species of livestock and
also in humans using the flow cytometric sperm sorting method. A guaranteed high sorting
accuracy is a key prerequisite for the widespread use of sperm sexing. The standard
validation method is flow cytometric remeasurement of the DNA content of the sexed sperm.
Since this method relies on the same instrument that produced the original sperm
separation, it is not truly independent. Therefore, to be able to specifically produce
either male or female offspring in the dog, we developed a method of direct visualization
of sex chromosomes in a single sperm using fluorescence in situ
hybridization (FISH) as a validation method. Denaturation of canine spermatozoa by
immersion in 1 M NaOH for 4 min yielded consistent hybridization results with over 97%
hybridization efficiency and a good preservation of sperm morphology. There was no
significant difference between the theoretical ratio (50:50) and the observed ratio of X-
and Y-chromosome-bearing spermatozoa in any of the three dogs. In addition, the mean
purities of flow-sorted sex chromosomes in spermatozoa of the three dogs were 90.8% for
the X chromosome fraction and 89.6% for the Y chromosome fraction. This sorting was
evaluated by using the dual color FISH protocol. Therefore, our results demonstrated that
the FISH protocol worked reliably for both unsorted and sexed sperm samples. 相似文献
47.
Maya Raman 《Journal Of Aquatic Food Product Technology》2013,22(5):454-467
Textural variations in squid mantle and the role of proteins on texture during frozen storage and cooking were investigated. Myofibrillar protein (62.36%) and pepsin soluble collagen (10.70%) accounted for the major fraction of total protein (22.17%). The histochemistry of mantle tissue showed a mesh-like arrangement of myofibrillar proteins with a collagenous dermal layer and feebly passing collagen through myotome bundles. Texture profile analysis of unfrozen mantle suggested the first phase of hardening at 50°C with hardness 1 (H1) of 11.53 kgf and hardness 2 (H2) of 9.68 kgf; and the second phase of hardening with optimal texture and maximum juiciness at 70°C (H1, 8.11 kgf; H2, 7.13 kgf) that varied with extended frozen storage. Increased frozen storage and cooking led to protein denaturation and formation of new low molecular weight proteins as evidenced in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE); these possibly influenced the functional and microstructural properties of the tissue. 相似文献
48.
Maya Gonzalez Marc Deconchat Gérard Balent Alain Cabanettes 《Annals of Forest Science》2008,65(5):511-511
49.
Because crop uptake of arsenic from soils poses a human health concern, this study examines the effect of plant species, neighborhood, and planting density on arsenic uptake by brassicas grown with companion crops. At a field site contaminated by arsenic and lead, we measured arsenic uptake in arugula (Eruca sativa) and collards (Brassica oleracea var. acephala) grown in arrangements varying in species diversity and density. We further tested the effect of species diversity on arsenic uptake in two greenhouse experiments with arsenic-spiked potting soil, one test using brassicaceous plants with intercropped pairs of arugula, collards, and kale (B. oleracea var. acephala). The other had intercropped pairs of arugula, lettuce (Lactuca sativa), and marigold (Tagetes patula). Arugula in all cropping arrangements accumulated the highest and most variable concentrations of arsenic compared to other species, with neither species diversity in the companion crops nor planting density affecting arsenic uptake. We observed increased phosphorus and sulfur uptake by arugula exposed to soil arsenic in the greenhouse brassica intercropping experiments, a result that may be explained by a biological response to arsenic or competition of arsenate with phosphate and sulfate for adsorption sites in the soil. Arsenic uptake was largely independent of plant-plant facilitation effects sometimes reported for other elements, possibly because of strong buffering of the bioavailable fraction of arsenic in the soils tested. 相似文献
50.
Ranjit S. Kataria Periasamy Kathiravan Shyam S. Bulandi D. Pandey Bishnu P. Mishra 《Tropical animal health and production》2010,42(5):849-855
The present study was undertaken to evaluate different Indian riverine buffalo breeds (Bubalus bubalis) for mutation drift equilibrium and occurrence of any recent genetic bottleneck. A total of 330 animals from seven different
breeds were analyzed with a set of 24 heterologous microsatellite markers. Three different tests revealed significant heterozygosity
excess in all the seven buffalo breeds studied when assumed under infinite alleles model of microsatellite evolution, while
it was the reverse with no significant heterozygosity excess when assumed under conservative stepwise mutation model. Under
the two-phase model, all the buffalo breeds except Mehsana were found to be in mutation drift equilibrium when evaluated by
all the three statistical methods. Standardized differences test and Wilcoxon signed-rank test revealed significant heterozygosity
excess suggesting possible cryptic demographic bottleneck in Mehsana buffaloes of Western India. 相似文献