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91.
Plasma progesterone- and LH concentrations were studied in lactating dairy cows around the superovulatory heat. The pattern of both hormones accurately reflected the donor animals' endocrine balance and could be used to evaluate and predict the subsequent potentials or quality of a given animal as embryo- and oocyte donor. It was the general impression that both PMSG- and FSH treatment caused endocrine changes in progesterone- and LH patterns that would account for improper oocyte- and embryo development. 相似文献
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Kaartinen MJ Cuvelliez S Brouillard L Rondenay Y Kona-Boun JJ Troncy E 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(7):725-730
This survey evaluates early perceptions about the use of medetomidine and atipamezole among veterinary practitioners in Quebec in 2002. Response rate was 23.5%; 71.1% of the practitioners did not use these products because of lack of information (69.3%), unavailability of the drugs in the practice (23.3%), or other reasons (7.3%), including concerns about the safety of alpha-2 agonists. Most veterinarians who used these products (70.4%) used them only rarely. Sedation by medetomidine was qualified as good (44.2%) or excellent (36%), and analgesia as good (46.5%) or average (32.7%). Waking up after atipamezole was qualified as good (47.5%) or excellent (40.9%). These perceptions indicate an opportunity for wider use of the products in veterinary practice. With more education and experience, practitioners could find medetomidine hydrochloride alone or in combination with an opioid useful for sedation, analgesia, and premedication for healthy animals. Reversal with atipamezole hydrochloride is considered effective, when residual sedation is undesirable. 相似文献
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Cu-enriched pig-mannre slurry was applied to grassland at two rates, 5000 and 10,000 gal/ac (56,000 and 112,000 I/ha), on three occasions, supplying a total of 5.4 Ib/ac (6.1 kg/ha) and 10.8 Ib/ac (12.2 kg/ha) Cu, respectively. At the higher rate, soil Cu extractable with EDTA increased from 24 ppm to 7.3 ppm Cu in samples taken to a depth of 3 in. (7.5 cm) and Cu in herhage DM increased from 9.1 ppm to 21.2 ppm Cu (mean of 5 cuts). Much of the additional Cu in the herhage was thought to be derived from external contamination. In other tests, leafy herbage sampled a few hours after applying slurry contained 338 ppm Cu in the DM. Samples of soil and herbage were taken in 1969, 1970 and 1971 from farm grassland that had received Cu-enriched pig-manure slurry each year; levels of Cu increased in the soil, Cu levels in herbage were variable and appeared to be affected by the rate of grass growth. The evidence suggests that there is at present littie risk of Cu toxicity following applications of Cu-enriched pig-manure slurry; the greatest risk to susceptible stock would appear to be by ingesting either grazed or conserved herbage contaminated with slurry. To avoid possible hazards from a build-up of Cu in the soil, a maximum annual application of ahout 8.5 Ib/ac (9.5 kg/ha) Cu is suggested until more is known on the availability of Cu in slurry to crops and grass. 相似文献
97.
Line Sass Kierkegaard Linn Fenna Groeneveld Anne Kettunen Peer Berg 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2020,69(1-2):2-24
ABSTRACTThe Nordic countries are committed to conserving farm animal genetic diversity. National reports on phenotypic and genetic characterization point towards a lack of characterization for many Nordic native breeds. Little to no knowledge on the traits of the animals and their derived products leads to potential remaining untapped. The objective of this study was to provide a quantitative assessment of phenotypic and genetic characterization of Nordic native breeds, through a literature search and obtaining census data. Six species and a total of 85 breeds were included. Studies were classified according to six different categories of characterization. Results showed that a large percentage of the breeds are not characterized at all. Moreover, most breeds have extremely low census sizes. A substantial effort to increase population sizes and document characteristics of Nordic native breeds, to promote conservation and sustainable use, is needed. 相似文献
98.
Rasmussen M Guo X Wang Y Lohmueller KE Rasmussen S Albrechtsen A Skotte L Lindgreen S Metspalu M Jombart T Kivisild T Zhai W Eriksson A Manica A Orlando L De La Vega FM Tridico S Metspalu E Nielsen K Ávila-Arcos MC Moreno-Mayar JV Muller C Dortch J Gilbert MT Lund O Wesolowska A Karmin M Weinert LA Wang B Li J Tai S Xiao F Hanihara T van Driem G Jha AR Ricaut FX de Knijff P Migliano AB Gallego Romero I Kristiansen K Lambert DM Brunak S Forster P Brinkmann B Nehlich O Bunce M Richards M Gupta R 《Science (New York, N.Y.)》2011,334(6052):94-98
We present an Aboriginal Australian genomic sequence obtained from a 100-year-old lock of hair donated by an Aboriginal man from southern Western Australia in the early 20th century. We detect no evidence of European admixture and estimate contamination levels to be below 0.5%. We show that Aboriginal Australians are descendants of an early human dispersal into eastern Asia, possibly 62,000 to 75,000 years ago. This dispersal is separate from the one that gave rise to modern Asians 25,000 to 38,000 years ago. We also find evidence of gene flow between populations of the two dispersal waves prior to the divergence of Native Americans from modern Asian ancestors. Our findings support the hypothesis that present-day Aboriginal Australians descend from the earliest humans to occupy Australia, likely representing one of the oldest continuous populations outside Africa. 相似文献
99.
J. C. Murdoch A. S. Foot M. J. Head Muriel C. Holdsworth Zena D. Hosking C. Line 《Grass and Forage Science》1959,14(4):247-252
The changes in chemical composition during haymaking, the loss of nutrients in the field and during storage, and the nutritive value of swath-cured and tripoded hay were compared. In good weather no advantage was gained by tripoding the hay. The nutritive value of the hays made by the two methods was similar and the loss of dry matter in the field slightly lower in the swath-cured hay. In a bad season, however, the nutrient loss in the swath-cured hay greatly exceeded that occurring in the tripoded hay and the starch equivalent, as shown by the results of digestibility trials, was markedly lower for the swath-cured. 相似文献
100.
This study examines the recovery of the microbial compartment following active restoration of a North American ombrotrophic peatland extracted for horticultural peat-based substrates and restored by the Sphagnum moss transfer method. We used phospholipid fatty acids (PLFAs) to portrait the microbial community structure and Community Level Physiological Profiles (CLPP) to describe the functional diversity of the microbial communities. Our results indicate that the PLFA profiles were different between the beginning and the end of the growing season, but that it was impossible to distinguish five different vegetation classes found along the disturbance-recovery gradient on the basis of the microbial community structure. The pH, the cover of mosses, Ledum groenlandicum and Eriophorum vaginatum var. spissum were the best environmental predictors for the PLFA composition. The newly formed peat found in aerobic conditions beneath restored Sphagnum carpets had the highest decomposition capacity, whereas the lowest rates were found in the surface samples of non-restored conditions or in the deepest horizons of the natural samples. A large proportion of the variation in the physiological profiles was explained with variables related to the vegetation cover, the physicochemical environment and the microbial structure of the community, which is very promising for future monitoring studies. Overall, this study demonstrates that the recovery of particular plant groups, namely mosses and shrubs in restored peatlands might be the driver of changes occurring in the structure of the microbial communities in restored peatlands. 相似文献