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421.
Flax fiber is an important textile material with excellent antibacterial activity and moisture wicking. Degumming of flax roving is essential in determining flax-fiber quality. Traditional degumming requires a large amount of chemicals to process flax roving. This study aimed to reduce the chemical usage and achieve cleaner production during this process by applying microbial treatment to degum flax roving. Microbial degumming instead of acid pickling and NaClO2-bleaching steps can no longer use H2SO4 and NaClO2, and the amount of alkali can be reduced by 50%. By analyzing the compositional changes of the main steps in traditional degumming processes and microbial-treatment sample, the application of Bacillus subtilis HR5 can achieve a good degumming effect. Results of environmental scanning electron microscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffractometry analyses showed that the gum was remarkably reduced, which can be confirmed by the gum components. Overall, the breaking tenacity and antibacterial activity of fibers degummed by microbial treatment were better than those treated by traditional degumming. These findings demonstrated the feasibility of microbial treatment as a solution for flax roving degumming. 相似文献
422.
《Fungal Ecology》2021
Four nematophagous fungi (NF) were identified by traditional and molecular techniques, and their in vitro predatory activity (PA) against Haemonchus contortus (Hc), and Panagrellus redivivus (Pr) was assessed. Additionally, the nematocidal activity (NA) of fungal organic extracts (OEs) obtained from a methanol/dichloromethane system was assessed. Fungi were grown in PDB medium under shaking (SchC) and static conditions (StatC). The PA of Arthrobotrys conoides (Ac), A. oligospora (Ao), A. arthrobotryoides (Aa) and Purpureocillium lilacinum (Pl) against Hc were 75, 71, 66 and 52%, respectively. Meanwhile, the PA against Pr for same fungal genera/species were 99.8, 99.9, 99.4 and 96.3%, respectively. The highest NA of the OEs were 89.5, 81.6 and 72.1% for Aa, Ac and Ao, respectively, under StatC. Moreover, Pl cultured under SchC caused 78% Hc larval mortality. The four assessed NF and their OEs are promising candidates as potential biocide agents against parasitic nematodes. 相似文献
423.
Plant cell suspension cultures and hairy roots are potential sources of secondary metabolites and recombinant proteins. In
contrast to traditionally grown “whole wild plants” or “whole transgenic plants”, their production in bioreactors guarantees
defined controlled process conditions and therefore minimizes or even prevents variations in product yield and quality, which
simplifies process validation and product registration. Moreover, bioreactors and their configuration significantly affect
cultivation results by accomplishing and controlling the optimum environment for effective cell growth and production of bioactive
substances. This review highlights the main design criteria of the most widely used bioreactor types, both for plant cell
suspension cultures and for hairy roots, and outlines suitable low-cost disposable bioreactors which have found increasing
acceptance over the last 10 years.
Plants for human health in the post-genome era, PSE congress 26.8.2007–29.8.2007, Helsinki. 相似文献
424.
Saussurea costus (Falc.) Lipsch. Syn. Saussurea lappa C.B. Clarke belongs to family Asteraceae and is a critically endangered plant that is monetarily very vital as a therapeutic herb of North - West Himalaya. Saussurea costus has been traditionally used to treat a variety of ailments in different indigenous health systems viz., carminative, expectorant, antiarthritic, antiseptic, aphrodisiac, anodyne and vermifuge without any noticeable adverse effects. Textbooks on ethnobotany, peer-reviewed academic publications, unpublished materials, and research repositories were used to collect the widespread review of literature on Saussurea costus. The scientific names were authenticated by using Kew Botanical Garden, International Plant Name Index and Plant List databases. Costunolide, dihydrocostunolide, sesquiterpene lactones and cynaropicrin have been identified as major phytoconstituents of Saussurea costus with great potency to develop as a drug candidate. Different pharmacological experiments convincingly confirmed the potential of Saussurea costus with anticancer, anti-ulcer, hepatoprotective activities, etc. providing support to the various traditional uses associated with Saussurea costus. Saussurea costus will be a preferable alternative for novel drug discovery due to its notable pharmacological properties. Although the existing information to far indicates the security and possibly efficacy of Saussurea costus, bioactive ingredients, physiological mechanisms, pharmacokinetics, accessibility, and the impact on human health are not fully understood. The present review piles up the up-to-date and widespread information on botany, traditional uses, phytochemistry and pharmacology of Saussurea costus, to assess its therapeutic potential, with a focus on in vitro, biomedical, and histopathological experiments. 相似文献
425.
In this Special Issue on “Nutraceuticals: Molecular and Functional Insights into how Natural Products Nourish the Brain”, the editors bring together contributions from experts in nutraceutical research to provide a contemporary overview of how select chemically identified molecules can beneficially affect brain function at the molecular level. Other contributions address key emergent issues such as bioavailability, formulation, blood brain permeability, neuronal health and inflammation that impact upon how nutraceuticals ultimately leverage the brain to function better. Whilst nutraceutical is used as marketing term, it has no regulatory definition, and there is a continuing need for licensing authorities to ensure that adequate guidelines exist pertinent to the safety to guide consumers internationally. In terms of the benefit of nutraceuticals is it clear that some naturally occurring molecules can be advantageous to both the young and aged brain, and that they have actions that ultimately can be directed to aid either in the improvement of cognition or in the management of debilitating neurodegenerative and neuropsychiatric conditions. 相似文献
426.
Antimalarial activities of gedunin and 7-methoxygedunin and synergistic activity with dillapiol 总被引:1,自引:0,他引:1
S OMAR K GODARD A INGHAM H HUSSAIN V WONGPANICH J PEZZUTO T DURST C EKLU M GBEASSOR P SANCHEZ-VINDAS L POVEDA B J R PHILOGENE J T ARNASON 《The Annals of applied biology》2003,143(2):135-141
Gedunin from Cedrela odorata (Meliaceae), a potent in vitro antimalarial agent, was investigated for its in vivo efficacy in CD‐1 mice infected with Plasmodium berghei. When orally administered at 50 mg kg‐1 day‐1 for 4 days, gedunin was able to suppress the parasitaemia level by 44%. However, no clear dose‐response effects were observed in the 0–100 mg kg‐1 day‐1 dose range. Preliminary pharmacokinetics in Sprague‐Dawley rats showed poor absorption. However, a binary treatment of 50 mg kg‐1 day‐1 gedunin with 25 mg kg‐1 day‐1 dillapiol, a cytochrome P450 inhibitor, increased parasitaemia clearance in mice to 75%. A clear dose‐response was observed in the 0–50 mg kg‐1 day‐1 gedunin dose range when administration was combined with 25 mg kg‐1 day‐1 dillapiol. In addition, 7‐methoxygedunin, a semi‐synthetic derivative which is more stable to degradation than gedunin, suppressed the level in mice by 67% at 50 mg kg‐1 day‐1. When administered at this dose in combination with 25 mg kg‐1 day‐1 dillapiol, clearance increased to 80%. These results demonstrate the potentialefficacy of antimalarial drugs and phytomedicines based on gedunin and the value of the combination therapy. 相似文献