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511.
Dupuy J Sutra JF Alvinerie M Rinaldi L Veneziano V Mezzino L Pennacchio S Cringoli G 《Veterinary parasitology》2008,157(3-4):284-290
The pharmacokinetics and mammary excretion of moxidectin and eprinomectin were determined in water buffaloes (Bubalus bubalis) following topical administration of 0.5mgkg(-1). Following administration of moxidectin, plasma and milk concentrations of moxidectin increased to reach maximal concentrations (C(max)) of 5.46+/-3.50 and 23.76+/-16.63ngml(-1) at T(max) of 1.20+/-0.33 and 1.87+/-0.77 days in plasma and milk, respectively. The mean residence time (MRT) were similar for plasma and milk (5.27+/-0.45 and 5.87+/-0.80 days, respectively). The AUC value was 5-fold higher in milk (109.68+/-65.01ngdayml(-1)) than in plasma (23.66+/-12.26ngdayml(-1)). The ratio of AUC milk/plasma for moxidectin was 5.04+/-2.13. The moxidectin systemic availability (expressed as plasma AUC values) obtained in buffaloes was in the same range than those reported in cattle. The faster absorption and elimination processes of moxidectin were probably due to a lower storage in fat associated with the fact that animals were in lactation. Nevertheless, due to its high excretion in milk and its high detected maximum concentration in milk which is equivalent or higher to the Maximal Residue Level value (MRL) (40ngml(-1)), its use should be prohibited in lactating buffaloes. Concerning eprinomectin, the C(max) were of 2.74+/-0.89 and 3.40+/-1.68ngml(-1) at T(max) of 1.44+/-0.20 and 1.33+/-0.0.41 days in plasma and milk, respectively. The MRT and the AUC were similar for plasma (3.17+/-0.41 days and 11.43+/-4.01ngdayml(-1)) and milk (2.70+/-0.44 days and 8.49+/-3.33ngdayml(-1)). The ratio of AUC milk/plasma for eprinomectin was 0.76+/-0.16. The AUC value is 20 times lower than that reported in dairy cattle. The very low extent of mammary excretion and the milk levels reported lower than the MRL (20ngml(-1)) supports the permitted use of eprinomectin in lactating water buffaloes. 相似文献
512.
The Rheo Extrusion Meter (REM) measures the time for vertical upward extrusion of wheat flour dough (subsequently referred to as extrusion time, ET) as a measure of its consistency. ET evidently increases with dough consistency. ETs are highly reproducible and sensitive to differences in dough moisture content. A single REM analysis takes 20 min, and the measured ET can be converted into the correct baking absorption at a given temperature. The heights of the extruded dough pieces are negatively correlated with straight‐dough bread loaf specific volume, both when comparing different flour samples and when adjusting moisture content of dough prepared from a given flour sample. The REM also allows determination of the consistency of complex wheat flour based systems and the impact of vital wheat gluten or ascorbic acid thereupon. Furthermore, in contrast to the farinograph, it detects the impact of endoxylanases hydrolyzing water‐extractable arabinoxylan on dough consistency. 相似文献
513.
Morar D Tijhaar E Negrea A Hendriks J van Haarlem D Godfroid J Michel AL Rutten VP 《Veterinary immunology and immunopathology》2007,115(1-2):146-154
Bovine tuberculosis (BTB) is endemic in African buffalo (Syncerus caffer) in the Kruger National Park (KNP). In addition to buffalo, Mycobacterium bovis has been found in at least 14 other mammalian species in South Africa, including kudu (Tragelaphus strepsiceros), Chacma baboon (Papio ursinus) and lion (Panthera leo). This has raised concern about the spillover into other potentially susceptible species like rhinoceros, thus jeopardising breeding and relocation projects aiming at the conservation of biodiversity. Hence, procedures to screen for and diagnose BTB in black rhinoceros (Diceros bicornis) and white rhinoceros (Ceratotherium simum) need to be in place. The Interferon-gamma (IFN-gamma) assay is used as a routine diagnostic tool to determine infection of cattle and recently African buffalo, with M. bovis and other mycobacteria. The aim of the present work was to develop reagents to set up a rhinoceros IFN-gamma (RhIFN-gamma) assay. The white rhinoceros IFN-gamma gene was cloned, sequenced and expressed as a mature protein. Amino acid (aa) sequence analysis revealed that RhIFN-gamma shares a homology of 90% with equine IFN-gamma. Monoclonal antibodies, as well as polyclonal chicken antibodies (Yolk Immunoglobulin-IgY) with specificity for recombinant RhIFN-gamma were produced. Using the monoclonals as capture antibodies and the polyclonal IgY for detection, it was shown that recombinant as well as native white rhinoceros IFN-gamma was recognised. This preliminary IFN-gamma enzyme-linked immunosorbent assay (ELISA), has the potential to be developed into a diagnostic assay for M. bovis infection in rhinoceros. 相似文献
514.
Jacques Fuchs 《Aquaculture (Amsterdam, Netherlands)》1978,15(1):63-74
The effect of photoperiod on survival and growth of cultured young soles (Solea solea) was investigated from hatching to the age of three months, at 18° C. Two experiments were performed, comparing days with 12, 18 and 24 h light. The fishes were reared in 60 1 tanks, conical ones before metamorphosis, square ones with a sandy bottom from metamorphosis to the age of three months. They were fed on live food organisms for 1 month, on frozen flesh of the bivalve Laevicardium crassum for the two other ones.During the larval period, no significant difference was recorded in the survival rate but a better growth was obtained with 18 and 24 h light, suggesting a predominant diurnal feeding. From metamorphosis to the age of three months (mean weight: 1 g) no significant effect of the photoperiod on the survival and growth of the juveniles could be demonstrated. 相似文献
515.
Sydney Malama Tone Bjordal Johansen John Bwalya Muma Sydney Mwanza Berit Djønne Jacques Godfroid 《Tropical animal health and production》2014,46(1):153-157
Bovine tuberculosis (BTB) is a chronic bacterial disease caused by Mycobacterium bovis. Infections due to M. bovis, which serves as a stable reservoir, can pose serious challenge to control and eradicate in both wildlife and livestock at the interface. This study aimed at isolating and characterizing M. bovis from Kafue lechwe (Kobus leche kafuensis) and black lechwe (Kobus leche smithemani) at the animal/human interface in Zambia. The samples with lesions compatible with BTB collected during the hunting seasons of 2009 and 2010 were cultured for isolation of mycobacteria using Stonebrink with pyruvate (BD Diagnostics, MD, USA) and Middlebrook 7H10 (BD Diagnostics) slants. Isolated mycobacteria were identified using IS6110 polymerase chain reaction and deletion analysis. Molecular characterization of the isolates was performed using spoligotyping and mycobacteria interspersed repetitive unit–variable number tandem repeat (MIRU–VNTR) with nine loci. Data was analyzed using BioNumerics software 6.1. Out of the 39 samples, acid fast bacilli were detected in 27 (69.2 %) based on smear microscopy. Seven isolates were found to belong to Mycobacterium tuberculosis complex, and all were identified as M. bovis based on deletion analysis. All seven isolates were identical on spoligotyping as belonging to the SB0120 (SIT 482). MIRU–VNTR differentiated the isolates into five different patterns. This study has confirmed that M. bovis circulates in the Kafue lechwe, and non-tuberculous mycobacteria were detected in the black lechwe in Zambia which represents a wildlife reservoir, with a potential to spillover to cattle and humans. Isolates of M. bovis from lechwe antelopes are much conserved as only one spoligotype was detected. The study has shown that three loci differentiated fairly well. This option is cheap and less laborious, and hence a better option in resource-strained country like Zambia. The study further showed that some of the loci recommended by the European Reference Laboratory are not suitable for typing M. bovis in Zambia. 相似文献
516.
517.
Pierre Planquart Catherine Massiani Jacques Rabier Bruno Coulomb Jean-Luc Boudenne 《Journal of Soils and Sediments》2006,6(4):221-230
Background, Aim and Scope
Most studies of sewage sludge disposal effects on plants have focused on high metal loadings. Less attention has been paid
to plant responses to trace metal loadings below the recommended limit values.
Materials and Methods:
Here, a lysimetric experiment was conducted to assess the uptake, distribution and binding of trace metals by metal-induced,
sulfhydryl-rich peptides (phytochelatins) in colza (Brassica napus, v. Jaguar) grown on a clayey, silty soil amended with
a sewage sludge compost containing trace metal contents far below the recommended limit values established by French legislation.
Chemical fractionation of unamended and sludge-amended soils was performed using a sequential extraction technique.
Results:
Copper concentrations in plant tissues were not affected by compost disposal. Its application at a single rate equivalent
to 30 t/ha stimulated the growth of plants. Lead was not detectable in the plant material (< 1 mg g-1 dry wt.). Plants grown
on the amended soil accumulated significantly more zinc than control plants. These phytochelatin complexes detected in leaves
had a lower molecular weight than those extracted from roots. Those extracted from roots were composed of one type of phytochelatins
(PCs) such as in leaves or a mixture of glutathione, PC2 and PC4. In comparison with control plants, sewage sludge compost
application caused the synthesis of longer chain PCs in roots and in leaves. Furthermore, in comparison with control roots,
glutathione and phytochelatin mixtures of higher molecular weight were detected in roots produced on the amended soil, whereas
no significant increase in \total\ Cu and Zn content was observed in these organs after sludge application.
Discussion:
Compost application induces a significant increase in the proportion of the most labile forms of zinc and especially its pH
4.7 acid-soluble forms and, as a consequence, a higher accumulation of zinc in plants. Effects of copper are limited due to
its strong affinity for humic substances and lead does not seem to be transported in any organ of plants. The presence of
phytochelatins, even in plants grown on the unamended soil, proved the ability of colza to synthesize them in the presence
of zinc and copper.
Conclusions:
These primary results seem to prove, on one hand, ability of colza (Brassica napus, v. Jaguar) to synthesize phytochelatins
as well as in roots, in leaves and, on the other hand, the sensitivity of the PC induction as suggested by their identification
in plants grown on the control soil. Synthesis of longer chain PCs in roots and in leaves, and formation of glutathione and
phytochelatin mixtures in roots, are plant responses to sewage sludge compost application.
Recommendations and Perspectives:
Phytochelatin analysis is thus supposedly able to be one of the bioindicators that may be used as an ecotoxicological risk
assessment of wastes. Due to its ability to synthesize phytochelatins, colza could be chosen as a plant test. Phytochelatin
analysis could also be limited to roots (more sensitive than leaves). However, further experiments are needed. Quantitative
analysis of phytochelatins had not been carried out due to insufficient amounts of pure phytochelatin standards, that had
allow us to better study relationships between trace metal amounts to vegetal response. 相似文献
518.
A simple dose-effect model expressing the relationships between lake acidity, weighted mean annual sulfate concentration in wet deposition, Ca, Mg and true color (as an index of organic anion concentration) is presented. The agreement between observed and estimated pH for more than a 1000 lakes is high according to the Pearson coefficients of correlation (0.81 to 0.90) and the standard error of estimation (0.22 to 0.27 pH unit). Results obtained with this model show that an airborne sulfate target loading of 20 kg ha?1 yr?1 would be too high to adequately protect sensitive lake ecosystems. A target loading of 15 kg ha?1 yr?1 in wet deposition would be best suited for the protection of the greater portion of sensitive lakes. However, a target loading of 10 kg ha?1 yr?1 would be required to protect the most sensitive lake ecosystems. 相似文献
519.
Effects of structural and functional connectivity and patch size on the abundance of seven Atlantic Forest bird species 总被引:3,自引:0,他引:3
We studied the importance of fragment size and structural and functional connectivity on the occurrence and abundance of seven Atlantic Forest bird species in 13 patches (13-275 ha) and three sites within a continuous forest (10,000 ha). We sampled birds with point counts and evaluated structural connectivity considering the presence of corridors and the degree of isolation. We defined functional connectivity by analyzing species movements using playbacks in forest corridors between fragments and in the surrounding matrix. Species differed in their responses to fragmentation. For the frugivorous species, Trogon surrucura, Carpornis cucullatus and Triclaria malachitacea, patch size was the main factor determining abundance. Two understory insectivorous species, Basileuterus leucoblepharus and Pyriglena leucoptera, were more affected by the degree of patch connectivity, the former by the presence of corridors and the latter by the distance between patches. The capacity of P. leucoptera to use corridors and open areas (i.e. functional connectivity) shaped its abundance pattern. Fragmentation had no effect on the abundance of Chiroxiphia caudata and had a positive effect on Batara cinerea. This study emphasizes the importance of considering species’ perceptions of landscape, especially functional connectivity, in understanding the effects of habitat fragmentation. 相似文献
520.
Jacques Alary Pierre Bourbon Paul Chovin Claude Delaunay Jean Esclassan Jean-Claude Lepert 《Water, air, and soil pollution》1974,3(4):555-562
This paper discusses a procedure involving absorption of NO2 on triethanolamine impregnated-papers according to a recent study of Levaggi, Siu and Feldstein. The used solid surfaces are Millipore filters, first impregnated by stirring them in a solution containing triethanolamine, glycerol and acetone before drying in an oven. Storage is made in a closed glass container. For sampling, check air flow rate to be about 30 l h?1 through filters. The sampling time depends on the actual concentration. Samples are then analyzed in a laboratory under Saltzman's colorimetric reaction. The composition of the reagents is slightly modificated (acetic acid is replaced by phosphoric acid to obtain pH 1). Color development needs 30 min and then absorbance is compared with a standardization curve built from dilute solutions of Na NO2. Absorption efficiencies of over 95% are attained with two impregnated filters in a filter holder and at about 301 h?1 flow rate. Stability of filters after sampling is evaluated at 2 or 3 weeks, so it is possible to store several filters before sending them (for example by mail) to the laboratory for analysis. The stoichiometric factor depends on the weight (expressed in μg) of NO2 collected on the filters and varies between 1.0 and 0.84. To measure NO, oxidation into NO2 is first required, for example with an O3 lamp. 相似文献