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61.
Chamomile (Matricaria chamomilla), a popular herb valued for centuries as a traditional medicine, has been used to treat various human ailments; however, its anticancer activity is unknown. We evaluated the anticancer properties of aqueous and methanolic extracts of chamomile against various human cancer cell lines. Exposure of chamomile extracts caused minimal growth inhibitory responses in normal cells, whereas a significant decrease in cell viability was observed in various human cancer cell lines. Chamomile exposure resulted in differential apoptosis in cancer cells but not in normal cells at similar doses. HPLC analysis of chamomile extract confirmed apigenin 7-O-glucoside as the major constituent of chamomile; some minor glycoside components were also observed. Apigenin glucosides inhibited cancer cell growth but to a lesser extent than the parent aglycone, apigenin. Ex vivo experiments suggest that deconjugation of glycosides occurs in vivo to produce aglycone, especially in the small intestine. This study represents the first reported demonstration of the anticancer effects of chamomile. Further investigations of the mechanism of action of chamomile are warranted in evaluating the potential usefulness of this herbal remedy in the management of cancer patients.  相似文献   
62.
This paper addresses the question, when are threatened or endangered species really recovered? The US Endangered Species Act enables the de-listing of species once demographic criteria are met. In the Greater Yellowstone ecosystem, two protected apex carnivores, grizzly bears (Ursus arctos) and wolves (Canis lupus), face removal from federal government protection due to population increases, a point at which they are expected to be integrated components of this ecosystem. We tested the assumption that these two carnivores are playing normative ecological roles in the Yellowstone ecosystem by comparing the extent to which wolves and bears have re-instilled anti-predator responses in a primary prey species, moose (Alces alces), within wolf and bear recovery zones. As a type of control, we contrasted female moose from two areas in Alaska with different predator regimes to those in Wyoming. Populations from mainland Alaska, a region with a relatively intact carnivore assemblage, responded significantly more to odors of both carnivores. In contrast, a basic anti-predator reaction was lacking in Wyoming; and responses to grizzly bear odor only nominally increased after dependent young experienced heightened mortality. Additionally, the level of response among Alaskan moose living under virtual predator-free conditions for 25+ years closely resembled that of conspecifics in Wyoming. That such striking variation in prey responses exists re-enforces critical ecological differences between predator-intact and -defunct systems. Thus, although grizzly bears and wolves in the Yellowstone area will most likely be de-listed within the next few years, whether such action would be ecologically defensible is arguable. At this point in the recovery process, these predators may currently have limited ecological impacts in large portions of this region, at least as gauged by one potentially important prey species, moose. Although our data suggest ecologically incomplete conditions, other indices of carnivore recovery that include responses of other important prey species such as elk (Cervus elaphus), may be more in tune with carnivore activities. We recommend that different types of ecological data available throughout recovery zones be used in consort with demographic criteria to evaluate when endangered carnivores are more fully integrated into their ecosystems. And, in the event of a disparity between these criteria, we also encourage a dialogue focusing on approaches towards bringing ecological conditions in concordance with demographic criteria, irrespective of whether one considers increasing population levels beyond the current target levels required for de-listing,and/or simply, additional time for the recovery process.  相似文献   
63.
64.
The dissipation behavior and degradation kinetics of azoxystrobin, carbendazim, and difenoconazole in pomegranate are reported. Twenty fruits/hectare (5 kg) were collected at random, ensuring sample-to-sample relative standard deviation (RSD) within 20-25%. Each fruit was cut into eight equal portions, and two diagonal pieces per fruit were drawn and combined to constitute the laboratory sample, resulting in RSDs <6% (n = 6). Crushed sample (15 g) was extracted with 10 mL of ethyl acetate (+ 10 g Na(2)SO(4)), cleaned by dispersive solid phase extraction on primary secondary amine (25 mg) and C(18) (25 mg), and measured by liquid chromatography tandem mass spectrometry. The limit of quantification was ≤0.0025 μg g(-1) for all the three fungicides, with calibration linearity in the concentration range of 0.001-0.025 μg mL(-1) (r(2) ≥ 0.999). The recoveries of each chemical were 75-110% at 0.0025, 0.005, and 0.010 μg g(-1) with intralaboratory Horwitz ratio <0.32 at 0.0025 μg g(-1). Variable matrix effects were recorded in different fruit parts viz rind, albedo, membrane, and arils, which could be correlated to their biochemical constituents as evidenced from accurate mass measurements on a Q-ToF LC-MS. The residues of carbendazim and difenoconazole were confined within the outer rind of pomegranate; however, azoxystrobin penetrated into the inner fruit parts. The dissipation of azoxystrobin, carbendazim, and difenoconazole followed first + first order kinetics at both standard and double doses, with preharvest intervals being 9, 60, and 26 days at standard dose. At double dose, the preharvest intervals extended to 20.5, 100, and 60 days, respectively.  相似文献   
65.
Comamonas sp. UVS was able to decolorize Reactive Blue HERD (RBHERD) dye (50 mg L?1) within 6 h under static condition. The maximum dye concentration degraded was 1,200 mg L?1 within 210 h. A numerical simulation with the model gives an optimal value of 35.71?±?0.696 mg dye g?1 cell h?1 for maximum rate (Vmax) and 112.35?±?0.34 mg L?1 for the Michaelis constant (Km). Comamonas sp. UVS has capability of decolorization of RBHERD in the presence of Mg2+, Ca2+, Cd2+, and Zn2+, whereas decolorization was completely inhibited by Cu2+. Metal ions also affected the levels of biotransformation enzymes during decolorization of RBHERD. Comamonas sp. UVS was also able to decolorize textile effluent with significant reduction in COD. The biodegradation of RBHERD dye was monitored by UV–vis spectroscopy, FTIR spectroscopy, and HPLC.  相似文献   
66.
Flying insects have evolved sophisticated sensory capabilities to achieve rapid course control during aerial maneuvers. Among two-winged insects such as houseflies and their relatives, the hind wings are modified into club-shaped, mechanosensory halteres, which detect Coriolis forces and thereby mediate flight stability during maneuvers. Here, we show that mechanosensory input from the antennae serves a similar role during flight in hawk moths, which are four-winged insects. The antennae of flying moths vibrate and experience Coriolis forces during aerial maneuvers. The antennal vibrations are transduced by individual units of Johnston's organs at the base of their antennae in a frequency range characteristic of the Coriolis input. Reduction of the mechanical input to Johnston's organs by removing the antennal flagellum of these moths severely disrupted their flight stability, but reattachment of the flagellum restored their flight control. The antennae thus play a crucial role in maintaining flight stability of moths.  相似文献   
67.
Water, Air, &; Soil Pollution - High applications of P fertilizers and manure are general practice in intensive agriculture and may cause eutrophication in adjacent streams. Bioavailability of P...  相似文献   
68.
To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials (DFM) for improved animal performance in te...  相似文献   
69.
Summary

During germination of seed of the tropical epiphytic orchid, Dendrobium crumenatum, cell division at the chalazal end of the globular embryo occurred after one week of culture on Vacin and Went medium. The larger cells at the middle and basal regions of the embryo continued to enlarge with distinct nuclei and chromatin, indicative possibly of endoduplication. Shoot apex organization at the chalazal end occurred after four weeks of culture. Mobilization of stored reserves was seen as a reduction in the granular nature of the cytoplasm after two weeks in culture. Utilization of protein reserves occurred within 6 d of germination. Subsequently, do novo synthesis and accumulation of cvs proteins increased steadily and reached an equilibrium between 18 and 24 d. Changes in profiles of specific proteins indicated development-specific protein accumulation. Two proteins of Mr 14 and 33 kDa were highly abundant in dry seeds but were degraded within 6 d of germination indicating their possible nutritive role in embryo development. Several other proteins showed steady increases during 24 d from germination.  相似文献   
70.
Summary

Mango (Mangifera indica L.) trees grown at high density show a decline in flowering and fruiting after good fruiting years as a result of various factors. Annual pruning can restore production and productivity in such trees. Chlorophyll, total sugars (TS), total phenolics (TP), and proline contents as well as polyphenol oxidase (PPO) activities, were measured in the 2005–2006 and 2006–2007 seasons in shoot buds with a few leaves in three mango cultivars (‘Amrapali’, ‘Mallika’, and ‘Dashehari’). Trees were grown at high density in an orchard and the aforesaid parameters were measured 1 month after different degrees of pruning (Stage I) and after subsequent fruit bud differentiation (FBD; Stage II). Severely-pruned mango trees had the highest contents of chlorophyll a, while chlorophyll b and total chlorophyll contents were found to be highest in moderately-pruned trees. Lightly-pruned trees had the highest contents of reducing sugars (RS), whereas TS contents were highest in severely-pruned trees. The contents of RS and TS increased in shoot buds during the FBD stage. A moderate intensity of pruning significantly increased TP contents, while the lowest TP contents were recorded in non-pruned trees. ‘Off’-year shoots had higher TP contents than ‘on’-year shoots. Irrespective of pruning intensity, shoot buds of ‘Mallika’ trees had the highest PPO activities, with lower levels in ‘Amrapali’ and ‘Dashehari’ shoot buds. PPO activities were reduced at the FBD stage in ‘on’-year shoots. Severely-pruned trees had the highest PPO activities, while the lowest PPO activities were recorded in lightly-pruned trees. Shoot bud proline contents were found to be highest in non-pruned trees, and decreased with increasing pruning intensity. Thus moderate pruning can be adopted in high density orchards to obtain sustainable production with improved maintenance of canopy architecture.  相似文献   
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