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21.
Summary The occurrence of natural triploid hybrids between tetraploid Solanum acauleBitter subsp. acaule and diploid S. infundibuliformePhilippi both tuber-bearing Solanums, in the Puna region of Jujuy, is reported. The natural hybrids, which are morphologically intermediate between their putative parents and completely male sterile, have a somatic chromosome number of 36. The artificial hybrids, obtained by crossing both parental species, closely resemble the natural ones thereby confirming their parentage. It is proposed to designate the natural hybrids Solanum x viirsooi hybr. nov. 相似文献
22.
Summary Evidence is provided that hybridization of the tetraploid (2n=4x=48), self-fertile tuber-bearing species Solanum acaule Bitt. with the diploid (2n=2x=24), self-incompatible, tuber-bearing S. megistacrolobum Bitt. takes place in several localities of the province of Jujuy in the high, cold plateaux of the Argentine Puna. The triploid hybrids (2n=3x=36) closely resemble S. acaule in growth habit, leaf morphology and floral structures and for this reason they can be easily overlooked for that species in the field. Experimental data show that S. acaule can be crossed with S. megistacrolobum though the crossability is rather low and variable according to the particular cross considered. The artificial hybrid obtained compares well with the natural hybrid in morphology and chromosome number. The hybrids, though almost completely male sterile, are successful colonizers of disturbed areas around farmers' dwellings, cattle enclosures and other areas where the soil is rich in organic matter.There is some evidence that the Tilcara material of S. acaule subsp. aemulans and the hybrids of S. acaule x S. megistacrolobum have some characters in common, which can be interpreted as having a similar origin.It is postulated that S. acaule subsp. aemulans, in Jujuy at any rate, is not a primitive form of S. acaule as thought by Hawkes and Hjerting, but rather a fertile hybrid derivative of S. acaule x S. megistacrolobum through the functioning of 2n gametes.We also provide evidence that S. bruecheri
Correll should not be considered a hybrid of S. acaulle x S. megistacrolobum but a synonym for S. gourlayi
Hawkes. The new name, S. x indunii
Okada et Clausen, is proposed to designate this hybrid. 相似文献
23.
Anders Kjær Glenn Nielsen Søren Stærke Morten Rahr Clausen Merete Edelenbos Bjarke Jørgensen 《American Journal of Potato Research》2017,94(6):573-582
The purpose of the study was to investigate the use of hyperspectral imaging (HSI) to detect and quantify chlorophyll (Chl) and total glycoalkaloid concentrations (TGA) in potatoes. To create a set of tubers with different concentrations of Chl and TGA, potatoes of four varieties were wounded or treated with red, blue, red/blue, UV-a, UV-b or UV-c light. HSI analyses were performed with a reflection based setup implemented in an industrial potato sorting machine. After hyperspectral analyses, the peel was sampled, and concentrations of Chl and total TGA were determined. Results showed that the HSI system predicted the concentrations of Chl with a relatively high degree of accuracy, and a prediction R2 value of 0.92. Prediction of TGA concentrations performed to a much lesser extent, and the overall prediction R2 value was only 0.21. Moderate soil covers only affected the prediction powers to a minor degree. 相似文献
24.
Rain gardens have been recommended as a best management practice to treat stormwater runoff. However, no published field performance data existed on pollutant removal capabilities. Replicated rain gardens were constructed in Haddam, CT, to capture shingled-roof runoff. The gardens were sized to store the first 2.54 cm (1 inch) of runoff. Influent, overflow and percolate flow were measured using tipping buckets and sampled passively. Precipitation was also measured and sampled for quality. All weekly composite water samples were analyzed for total phosphorus (TP), total Kjeldahl nitrogen (TKN), ammonia-nitrogen (NH3-N), and nitrite+nitrate-nitrogen (NO3-N). Monthly composite samples were analyzed for copper (Cu), lead (Pb) and zinc (Zn). Redox potential was measured using platinum electrodes. Poor treatment of NO3-N, TKN, organic-N, and TP in roof runoff was observed. Many Cu, Pb and Zn samples were below detection limit, so statistical analysis was not performed on these pollutants. The only pollutants significantly lower in the effluent than in the influent were NH3-N in both gardens and total-N in one garden. The design used for these rain gardens worked well for overall flow retention, but had little impact pollutant concentrations in percolate. These results suggest that if an underdrain is not connected to the stormwater system, high flow and pollutant retention could be achieved with the 2.54 cm design method. 相似文献
25.
Oxidation of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) by lactoperoxidase was found to be inhibited by tyrosine-containing random amino acid copolymers but not by tyrosine. Both electrostatic effects and polymer size were found to be important by comparison of negatively and positively charged copolymers of varying lengths, with poly(Glu, Tyr)4:1 ([E 4Y 1] approximately 40) as the strongest competitive inhibitor (EC 50 approximately 20 nM). This polymer did not form dityrosine in the presence of lactoperoxidase (LPO) and peroxide. Furthermore, incubation with tert-butyl hydroperoxide, as opposed to hydrogen peroxide, resulted in a peculiar long lag phase of the reaction between the redox intermediate compound II and [E 4Y 1] approximately 40, indicating a very tight association between enzyme and inhibitor. We propose that interactions between multiple positively charged areas on the surface of LPO and the polymer are required for optimal inhibition. 相似文献
26.
Vaughn K McClain C Carrier DJ Wallace S King J Nagarajan S Clausen E 《Journal of agricultural and food chemistry》2007,55(12):4704-4709
High-value phytochemicals could be extracted from biomass prior to the current cellulosic pretreatment technologies (i.e., lime, ammonia, dilute acid, or pressurized hot water treatments) provided that the extraction is performed with a solvent that is compatible with the pretreatment. This work reports on the extraction of flavonoids from Albizia julibrissin biomass. While extracting A. julibrissin foliage with 50 degrees C water, 2.227 mg/g of hyperoside and 8.134 mg/g quercitrin were obtained, which is in the realm of what was obtained with 60% methanol. A. julibrissin foliage, flower, and whole plant extracts were tested in terms of their potential to inhibit low-density lipoprotein (LDL) oxidization. The highest inhibition was obtained with foliage water extracts, which were standardized at 2.5 microM of flavonoids. Also, the 2.5 microM foliage water extract resulted in a reduction from 43% to only 1% of the observed monocyte adherence. To have commercial application, A. julibrissin water extracts should be devoid of toxicity. The A. julibrissin foliage, flower, and whole plant water extracts were not toxic to Vero 76 cells. In summary, A. julibrissin biomass can be extracted with 50 degrees C water to yield an antioxidant stream, showing that it may be possible to couple extraction of valuable phytochemicals to the cellulosic pretreatment step. 相似文献
27.
Anthony D. Fox Hans E. Jrgensen Erik Jeppesen Torben L. Lauridsen Martin Sndergaard Karsten Fugl Palle Myssen Thorsten J.S. Balsby Preben Clausen 《水产资源保护:海洋与淡水生态系统》2020,30(2):237-245
- Breeding waterbird communities have suffered globally from the effects of anthropogenic changes in water quality (especially nutrient enrichment) in recent decades, but few studies have demonstrated the positive effects of restorative actions.
- Annual breeding waterbird surveys in the period 1977–2005 at two restored southern Danish lake basins (combining nutrient load reduction and biomanipulation) showed an up to five‐fold increase in abundance, and considerable changes in species richness and diversity, following restoration to clear water status in both lakes.
- Parallel surveys at a third lake, which retained clear water quality throughout, offering a form of natural ‘control', showed no such changes over the same time period.
- Consistent relationships between breeding waterbird abundance, species richness, and diversity with measures of water clarity (Secchi disc depth, chlorophyll a, and suspended matter) suggest that water clarity mainly drives the relationship; inverse relationships between these measures and total nitrogen and phosphorus were less consistent than for water clarity.
- The results suggest that an improvement in water clarity plays a key role in restoring breeding waterbird communities and suggest that breeding waterbirds can be indicators of the success of lake restoration projects, but more studies are needed to confirm their wider utility under a variety of conditions.
28.
Frode Guul-Simonsen Preben Stordal Christiansen Dan Edelsten Jørgen Ryhmer Kristiansen Niels Peder Madsen Egil Waagner Nielsen 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(2):105-110
Abstract Full-scale experiments with cooling of raw milk of good initial quality from a herd of 70 dairy cows have been performed under practical farm conditions, with different cooling and storage conditions, including instant cooling in a continuous process versus normal cooling in a batch process. During each milking, the milk was divided equally and successively for different cooling procedures. Quality evaluations (number of bacteria, acidity and oxidation of fat, sensoric quality) indicated that instant cooling/continuous process compared with normal cooling/batch process over 2.5 hours, both to 4°C, resulted in a slightly slower bacterial growth and a slightly slower hydrolysis and oxidation of milk fat. Instant raw milk cooled and stored at 2.5°C maintained a good quality for about one to two days more than when normal cooling over 1.5 hours and storing at 4°C was used. 相似文献
29.
Line Olsen Preben Boysen Caroline Piercey ?kesson Gjermund Gunnes Timothy Connelley Anne K Storset Arild Espenes 《Veterinary research》2013,44(1):109
Natural killer (NK) cells are important for immune protection of the gut mucosa. Previous studies have shown that under pathologic conditions NK cells, T cells and dendritic cells are found co-localised in secondary lymphoid organs where their interaction coordinates immune responses. However, in the gut-associated lymphoid tissues (GALTs), there are few detailed reports on the distribution of NK cells. Sheep harbour several types of organised lymphoid tissues in the gut that have different functions. The ileal Peyer’s patch (IPP) functions as a primary lymphoid tissue for B cell generation, while the jejunal Peyer’s patches (JPPs) and colon patches (CPs) are considered secondary lymphoid tissues. In the present study, we analysed tissues from healthy lambs by flow cytometry and in situ multicolour immunofluorescence, using recently described NCR1 antibodies to identify ovine NK cells. Most NCR1+ cells isolated from all tissues were negative for the pan T cell marker CD3, and thus comply with the general definition of NK cells. The majority of NCR1+ cells in blood as well as secondary lymphoid organs expressed CD16, but in the GALT around half of the NCR1+ cells were negative for CD16. A semi-quantitative morphometric study on tissue sections was used to compare the density of NK cells in four compartments of the IPPs, JPP and CPs. NCR1+ cells were found in all gut segments. Statistical analysis revealed significant differences between compartments of the primary lymphoid organ IPP and the secondary lymphoid organs of the JPPs and CP. NK cells co-localised and made close contact with T cells, dendritic cells and other NK cells, but did not show signs of proliferation. We conclude that NK cells are present in all investigated segments of the sheep gut, but that presence of other innate lymphoid cells expressing NCR1 cannot be excluded. 相似文献
30.
Birthe M. Damgaard Tove N. Clausen Søren K. Jensen Ricarda M. Engberg 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):19-29
The effects of different dietary levels of marine lipids in the diets with a constant distribution of metabolizable energy (ME) on protein, fat and carbohydrate were investigated in male mink kits in the growing-furring period during 2 consecutive years. The physiological investigations included 15 males per experimental group, each consisting of about 75 males. Fat herring and mackerel scrap were used in amounts resulting in levels of marine lipids of 30, 50 and 70% of total dietary lipid, respectively. Defatted herring scrap was used in proportions of 12, 23 and 32% in the diets. Haematocrit value, haemoglobin concentration, number of erythrocytes, leucocytes and platelets, plasma activities of alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT) and creatine kinase (CK), concentrations of tocopherols in plasma, liver and adipose tissue, composition of fatty acids (FA) in liver and adipose tissue, body weight, weight of liver and heart in relation to body weight, and liver fat content were studied. The number of platelets decreased with an increasing proportion of marine lipids of total content of dietary lipids. A high intake of fatty fish products had no influence on the health status of the animals evaluated by haematological and clinical-chemical analyses, vitamin E status and FA composition in growing-furring male mink. No negative effects on the health of the animals were demonstrated when feeding with defatted herring scrap. 相似文献