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91.
This study identifies the potential use of the combined application of hardwood-derived biochar (BC) and phytohormone-producing endophytes for enhancing crop production under heavy metal stress. For this purpose, the endophyte Galactomyces geotrichum WLL1 was isolated from Trapa japonica inhabiting a Korean river whose rainfall catchment area included an abandoned zinc mine. Pyrolyzed BC derived from pine hardwoods was obtained commercially. Under growth chamber conditions, the combined or individual application of G. geotrichum WLL1 and BC (15 % w/w) significantly improved soybean growth with or without excess Zn (5,253.6 mg kg?1). The beneficial effect of treatments was observed in the low uptake of Zn by different plant tissues and its immobilization in the soil. Biochar and G. geotrichum WLL1 shared their beneficial properties synergistically and improved plant growth characteristics with or without Zn heavy metal stress (HMS). Further, intensive root colonization of G. geotrichum WLL1 in the presence of BC was observed irrespective of HMS. Most interestingly, BC and G. geotrichum WLL1 had a priming effect by inducing systemic resistance in soybeans as revealed by significantly large amounts of jasmonic acid. These properties of BC could be exploited under abiotic and biotic stress. Here, for the first time, the combined application of hardwood-derived BC and phytohormone-producing endophytes is recommended for environmentally friendly and cost-effective crop production under HMS.  相似文献   
92.

Background:

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is an infectious zoonotic pathogen causing human infections. These infections, in some cases, can lead to hemolytic uremic syndrome and its life-threatening complications and even death worldwide. The first intimate bacterial adhesion, intimin (I), with its own receptor translocated intimin receptor (Tir) and E. coli secreted protein A, acting as Tir conduit, are highly immunogenic proteins for vaccine development against E. coli O157:H7.

Methods:

A chimeric trivalent recombinant protein was previously found to be a suitable strategy for developing vaccines against E. coli O157:H7. In this study, the recombinant EIT (rEIT) was used to design a protective EHEC nasal nanovaccine. Chitosan and its water-soluble derivative, trimethylated chitosan (TMC), as muco-adhesive biopolymers, are good candidates for preparation of nanovaccines.  Using the electrospraying technique, as a novel method, we could obtain particles of rEIT loaded with chitosan and TMC on a nanometer scale. Mice were immunized with intranasal administration or intrapretoneal injection of rEIT.

Results:

The rEIT-specific immune responses (IgG and IgA) were measured by indirect ELISA. Only nasal administration of chitosan electrospray and TMC formulation produced significant secretion IgA. Intranasal administration of nanovaccine reduced the duration of bacterial fecal shedding on mice challenged with E. coli O157:H7.

Conclusion:

Since development of mucosal vaccines for the prevention of infectious diseases requires efficient antigen delivery; therefore, this research could be a new strategy for developing vaccine against E. coli O157:H7.Key Words: EnterohemorrhagicEscherichia coli, Nanoparticles, Intranasal vaccination  相似文献   
93.
Gesunde Pflanzen - Foliar application of micronutrients and plant growth regulators (PGRs) is one of the strategies of plant-feeding direct through leaves to allow rapid uptake irrespective of soil...  相似文献   
94.
Latif G. Samaan 《Euphytica》1982,31(1):167-173
Summary A serological comparison of pollen proteins from Clementine tangerine versus those of 5 other morphologically similar Citrus cultivars was made to measure the degree of genetic relationships with Clementine. Among the tested Citrus cultivars the most related to Clementine were Baladi mandarin and Baladi blood orange. whereas Sour orange and Satsuma mandarin were least related. These findings support previous observations based on morphological characteristics, that the possible seed parent to Clementine was Baladi mandarin. The serological evidence also indicates that Baladi blood orange could be the pollen parent.  相似文献   
95.
Rheological properties of intermediate moisture (35-45% wet basis) doughs from pregelatinized and raw wheat starch blends of various ratios were characterized using off-line capillary rheometry and online slit-die extrusion. In the case of capillary rheometer, viscosity of blends decreased by up to 50% as pregel starch concentration increased from 5 to 45%, whereas tests could not be conducted beyond 45% pregel starch concentration. For slit-die extrusion, viscosity was at a minimum at 60% pregel concentration, and it decreased by as much as 65% as pregel concentration increased from 0 to 60%. As pregel concentration increased (from 5 to 45% for the rheometer and from 0 to 60% for the extruder), the amount of water available in the system for gelatinization of existing raw starch granules decreased due to the stronger water-binding capacity of pregelatinized starch. This led to decreased additional conversion in the rheometer and extruder, which in turn caused a decrease in the volume fraction of starch and a reduction in viscosity.  相似文献   
96.
Cumulative infiltration into thesoil profile during constant on-off cycletimes of surge irrigation was estimatedusing surge-ring infiltrometer data. TheKostiakov equation was employed to modelthe cumulative infiltration behaviour andits reduction into the soil duringdifferent surges. The two-point techniquewas applied to determine the unknownparameters of the Kostiakov equation. Itwas concluded that the surging phenomenasubstantially reduced water movement andthe reduction in cumulative infiltrationvaries from 60 to 83% during first surgeand 60 to 27% for the subsequent surges. Asurge infiltration model was also developedby introducing a `surge factor' into theKostiakov equation to generate infiltrationdata for subsequent surges, using the firstsurge / continuous infiltration data.Results of the study revealed that theinfiltration data of the surge-ringinfiltrometer and that generated by surgeinfiltration model matched closely.  相似文献   
97.
Eight cattle immunized with cattle-derived Theileria parva Boleni stabilate together with six susceptible controls were released in Dombawera Game Park on the Highveld of Zimbabwe. This coincided with Rhipicephalus appendiculatus nymphal activity. The cattle grazed together with African buffaloes (Syncerus caffer) and were not treated against tick infestation. The nymphal tick infestation was high, and seven of the eight immunized cattle and three of the controls had severe and fatal reactions. Subsequently, two stocks of Theileria parva to be tested for their immunizing abilities were prepared-one from adult ticks which were fed as nymphs on one of the sick control animals (Dom 268) and the other from adult ticks collected from pastures grazed by buffaloes (Bv-1). Two groups of cattle were immunized with either the Dom 268-derived strain (eight animals) or the Bv-1-derived strain (four animals). These together with three non-immunized controls, were released in Bally Vaughaun Game Park in the Highveld, where buffaloes are present, during the season of nymphal tick activity. A third group of five cattle, immunized with stabilate Bv-1, and three non-immunized controls were released at the same site during the season of adult tick activity. The nymphal and adult tick infestations of the cattle were large and more than 2000 nymphs and 1000 adult ticks were counted per animal. Cattle were treated with a pyrethroid pour-on preparation to control the tick infestation and screw-worm strike. The immunized cattle in the three groups survived the theileriosis challenge for a period of 18 months, but the non-immunized control cattle suffered a severe and fatal theileriosis 19-23 days after being placed on the pasture.  相似文献   
98.
99.
Extruded breakfast cereals (EBC), processed from two oat lines, N979-5-2-4 (N979) and "Jim", with beta-glucan concentrations of 8.7 and 4.9%, respectively, were used to determine the impact of dry solids (DS) and bile acid (BA) concentrations on in vitro BA binding efficiency. A full fractional factorial design with levels for BA concentrations of 0.20, 0.47, 0.95, 2.37, and 4.73 micromol/g of total EBC slurry and for DS in the slurries of 0.8, 2, 3, and 4% (w/w) was selected. The absolute amount of BA bound (micromol) was measured for each trial in the experiment design. The percentage (%) of BA bound based on the total amount of BA added and BA bound per gram of DS of the EBC (micromol/g) were also presented and discussed. N979 in vitro digestion slurries had greater BA binding (micromol) than Jim slurries at different DS and BA concentrations, with greater differences at DS of 3% or above and at BA concentrations of 2.37 micromol/g or above. No difference in the absolute amount of BA bound (micromol) and percentage (%) BA bound occurred between the EBC slurries made from the two oat types at the lowest DS of 0.8% or the lowest BA concentration of 0.20 micromol/g. The efficiency of BA binding by beta-glucan in these two EBC became more distinguishable at 3% DS or above and BA concentrations of 2.37 micromol/g or above, indicating that these two conditions can be employed to measure BA capacities for similar foods. Also, the beta-glucan in the EBC produced from the N979 oat line was more soluble than that from the EBC produced from the Jim oat line. Thus, greater BA binding capacity may have been caused by both a greater amount of beta-glucan and a greater solubility of beta-glucan in N979 than in Jim EBC.  相似文献   
100.
We investigate the effects of anthropogenic activities on the Lower Sakarya River. The impacts of dam, levee, and bridge constructions, sand-gravel mining activities and water withdrawals during the industrialization period of the Sakarya River Basin have been explored by analyzing flow, sediment and channel cross section data from different periods in time by comparing pre- and post-1975 periods. The year 1975 is roughly determined to be commencement of heavy human activities. Assessment of data shows that average annual flow is reduced by almost 20% after 1975. Due to increased regulations after 1975 flow became less variable, i.e. low-flows are increased and high-flows are reduced. Flow showed less variation with seasons during the post-1975 period compared to the pre-1975 period. Close inspection of precipitation and temperature patterns over the course of this period indicates that these changes in the flow regime cannot be attributed to natural causes and must be instigated by anthropogenic activities. Analyses of sediment data point toward a consistent reduction in sediment concentration and loadings with years in the Lower Sakarya River. Sediment rating curves developed for pre- and post-1975 exhibit a similar pattern. The impact of the anthropogenic activities on the river cross section is also examined by employing data from 1965, 2003 and 2006 at various points along the river profile. We found as much as 1 m aggradation at the thalweg elevation along the river profile starting from the river mouth up to the 12th km. Degradation in thalweg elevation is observed upstream of the 12th km, as much as 7 m at some locations. This research clearly undermines how human activities can alter the river hydrology and morphology. The adverse impacts of these modifications on the stream ecology in the Lower Sakarya River unfortunately remain unresolved.  相似文献   
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