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Ericaria crinita and Ericaria amentacea from the Adriatic Sea (Croatia) were investigated with respect to the presence of less-polar compounds for the first time after fractionation by solid-phase extraction (SPE). The composition of less-polar fractions of freeze-dried E. crinita (FdEc) and E. amentacea (FdEa) were analyzed by high-performance liquid chromatography–high-resolution mass spectrometry with electrospray ionization (UHPLC-ESI-HRMS). The major identified compounds were: amides of higher aliphatic acids (palmitoleamide, linoleamide, palmitamide, oleamide and erucamide) and related compounds, carotenoid (fucoxanthin), chlorophyll derivatives (pheophytin a and b and their derivatives) and higher terpenes (loliolide, isoamijiol with its oxidation product), β-stigmasterol and (3β,6α)-14-methylergosta-8,24(28)-diene-3,6-diol). The toxic effects observed on the less-polar fractions obtained from Ericaria species on zebrafish Danio rerio embryos could be associated with the high abundance of all five detected amides. The antioxidant activity of the fractions was evaluated by means of five independent assays, including the reduction of the radical cation (ABTS), the oxygen radical absorbance capacity (ORAC), ferric-reducing antioxidant power (FRAP), the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay and the Folin–Ciocalteu method. A higher antioxidant activity of E. amentacea in comparison to that of the E. crinita fractions was found with IC50 concentrations of 0.072 and 1.177 mg/mL, respectively. The correlation between the activity and the chemical composition revealed that the synergistic effect of different compounds impacted their antioxidant response.  相似文献   
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Signaling pathways transmit information through protein interaction networks that are dynamically regulated by complex extracellular cues. We developed LUMIER (for luminescence-based mammalian interactome mapping), an automated high-throughput technology, to map protein-protein interaction networks systematically in mammalian cells and applied it to the transforming growth factor-beta (TGFbeta) pathway. Analysis using self-organizing maps and k-means clustering identified links of the TGFbeta pathway to the p21-activated kinase (PAK) network, to the polarity complex, and to Occludin, a structural component of tight junctions. We show that Occludin regulates TGFbeta type I receptor localization for efficient TGFbeta-dependent dissolution of tight junctions during epithelial-to-mesenchymal transitions.  相似文献   
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Protein content and properties in the seminal plasma of Atlantic halibut (Hippoglossus hippoglossus) were assayed using spectrophotometric and electrophoretic methods. The protein concentration ranged from 6.4 ± 3.1 to 19.4 ± 3.4 mg ml−1 and anti-proteolytic activity from 585.2 ± 104.6 to 2912.4 ± 367.4 U l−l. A high correlation between anti-proteolytic activity and protein concentration (r = 0.95), and between sperm concentration and osmolality was found (r = 0.92). There was a significant decrease in anti-proteolytic activity from the first to the second sampling, but not in protein concentration. Anti-proteolytic activity and protein concentration were significantly affected by variations in individual males. Electrophoresis revealed four anti-proteolytic bands and individual differences in bands of proteolytic activity, which were subsequently characterized as metalloproteases and serine proteases.  相似文献   
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Spontaneous electrical signals in the retina's photoreceptors impose a limit on visual sensitivity. Their origin is attributed to a thermal, rather than photochemical, activation of the transduction cascade. Although the mechanism of such a process is under debate, the observation of a relationship between the maximum absorption wavelength (λ(max)) and the thermal activation kinetic constant (k) of different visual pigments (the Barlow correlation) indicates that the thermal and photochemical activations are related. Here we show that a quantum chemical model of the bovine rod pigment provides a molecular-level understanding of the Barlow correlation. The transition state mediating thermal activation has the same electronic structure as the photoreceptor excited state, thus creating a direct link between λ(max) and k. Such a link appears to be the manifestation of intrinsic chromophore features associated with the existence of a conical intersection between its ground and excited states.  相似文献   
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An experiment was carried out to determine how the late application of nitrogen (N) fertilizer affects the use of pre‐anthesis carbon reserves during the grain‐filling period of pot‐grown wheat with no water shortage. Increasing doses (equivalent to 0, 140, and 180 kg N ha–1) of N fertilizer were applied, either in two amendments (stages GS20 and GS30) or in three amendments (stages GS20, GS30, and GS37, according to Zadoks scale). The management of fertilizer by combining an increased N rate with late N application was able to stimulate canopy development, to raise photosynthetic capacity and carbohydrate accumulation during the vegetative stages, and to increase grain yield. Based on the dynamics of carbohydrate accumulation in the ear, three phases were differentiated during the grain‐filling period, whose temporary pattern remained stable regardless of the fertilizer management. The net remobilization of carbohydrates started 12 d after anthesis from the leaves and 28 d after anthesis from roots and stems. The increase of the N dose with late N application allowed on one hand a lower use of the pre‐anthesis carbon reserves in favor of greater de novo photosynthesis during the grain‐filling period, and on the other hand greater relative contribution of the leaf and ear C reserves to remobilization towards the grain. Further splitting the dose increased only the relative contribution of ear C reserves. The stem contribution seemed to be independent of N applied whereas the root contribution tended to diminish with late N application.  相似文献   
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Zusammenfassung Die Angaben eines 4jährigen Anbaus von zwei ingezüchteten Elternstämmen (buschförmigerCucurbita pepo L.) mit ihren F1- und F2-Generationen wurden für eine Analyse der Ertragskomponenten (reife Früchte) ausgewertet. Es wurde eingehend die Variabilität zwischen den Pflanzen, zwischen den Jahren und zwischen den Generationen verglichen und diskutiert. Folgende genetische Konsequenzen der Untersuchung sind wahrscheinlich:1. Die Anzahl der reifen Früchte je Pflanze ist stark umweltabhängig und zeigt eine Tendenz zu Heterosis.2. Das durchschnittliche Gewicht einer Frucht läßt sich am wenigsten von den Jahresbedingungen beeinflussen (hohe Heritabilität) und vererbt sich intermediär.3. Das daraus resultierende Gewicht der Früchte je Pflanze ist (wie die Fruchtanzahl) stark umweltabhängig; das hohe Fruchtgewicht vererbt sich aber dominant, wahrscheinlich deswegen, weil die Heterosistendenz der Anzahl der Früchte nicht genügend stark ist, um die konservative Heritabilität des Einzelfruchtgewichtes zu durchbrechen.4. Die Variabilität der F2-Generation war für alle Merkmale stärker als die der F1, die Mittelwerte der Merkmale aber waren für F1 und F2 nicht signifikant verschieden.
Summary Data of a four years growing of two inbred parent lines (Zucchini, bush,Cucurbita pepo L.) and their F1- and F2-generations have been used for an analysis of yield components (ripe fruits). Variability between plants, between years and between generations was thoroughly compared and discussed. The following genetic consequences of the investigation are probable:1. The number of ripe fruits per plant is highly dependent on the environment and shows a tendency towards heterosis.2. The mean weight of one fruit is least influenced by the conditions during the year (high heritability) and shows intermediary inheritance.3. The weight of the fruits per plant resulting from the above (as well as the number of fruits) is highly influenced by the environment; the high weight of fruits is dominant. The reason for this may be, that the tendency for heterosis concerning the number of fruits is not potent enough to break the conservative heritability of single fruit weight.4. The variability in F2 was found to be larger for all characters than in F1 but both generations showed no significant differences in the mean values of the characters tested.

F1, F2, (Cucurbita pepo L., ) 4 ; . , . , :1. ; .2. ( ); .3. , , ( ), , , , , , .4. F2 , F1, F1 F2 - .
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Summary A model for the isothermal transport of bound water through the cell wall of wood is developed, based on the assumption that the driving force for moisture movement is the gradient of spreading pressure , as first proposed by Babbitt (1950). This pressure is a surface phenomenon, derivable from the surface sorption theory of Dent (1977), a modification of the BET sorption theory. The force resisting moisture transport is assumed to be inversely proportional to moisture content and directly proportional to the equivalent viscosity of the sorbed water, calculated to be orders of magnitude larger than that of free water. The coefficients normally used to describe isothermal moisture transport in wood are derived from the model, and their predicted behavior as functions of the relative vapor pressure h of the cell wall are described graphically. An attempt is made to calculate a quantitative magnitude for the diffusion coefficient D, based on an assumed relationship between viscosity and the activation energy for water diffusion.  相似文献   
10.
Gender determination is frequently requested by reptile breeders, especially for species with poor or absent sexual dimorphism. The aims of the current study were to describe techniques and diagnostic sensitivities of ultrasound, radiography, and computed tomography for gender determination (identification of hemipenes) in four species of lizards. Nineteen lizards of known sex, belonging to four different species (Pogona vitticeps, Uromastyx aegyptia, Tiliqua scincoides, Gerrhosaurus major) were prospectively enrolled. With informed owner consent, ultrasound, noncontrast CT, contrast radiography, and contrast CT (with contrast medium administered into the cloaca) were performed in conscious animals. Imaging studies were reviewed by three different operators, each unaware of the gender of the animals and of the results of the other techniques. The lizard was classified as a male when hemipenes were identified. Nineteen lizards were included in the study, 10 females and nine males. The hemipenes were seen on ultrasound in only two male lizards, and appeared as oval hypoechoic structures. Radiographically, hemipenes filled with contrast medium appeared as spindle‐shaped opacities. Noncontrast CT identified hemipenes in only two lizards, and these appeared as spindle‐shaped kinked structures with hyperattenuating content consistent with smegma. Hemipenes were correctly identified in all nine males using contrast CT (accuracy of 100%). Accuracy of contrast radiography was excellent (94.7%). Accuracy of ultrasound and of noncontrast CT was poor (64.3% and 63.1%, respectively). Findings from the current study supported the use of contrast CT or contrast radiography for gender determination in lizards.  相似文献   
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