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1.
Early iron deficiency in rat does not affect the weight or the protein, DNA, and RNA content but results in a slight reduction in gamma-aminobutyric acid (GABA) (13%, p less than 0.01) and glutamic acid (20%, p less than 0.001) content of the brain. The activities of the two GABA shunt enzymes, glutamate dehydrogenase and GABA-transaminase, and of the NAD+-linked isocitrate dehydrogenase (ICDH) were inhibited whereas the glutamic acid decarboxylase, mitochondrial NADP+-linked ICDH, and succinic dehydrogenase activities remained unaltered in brain. On rehabilitation with the iron-supplemented diet for 1 week, these decreased enzyme activities in brain attained the corresponding control values. However, the hepatic nonheme iron content increased to about 80% of the control, after rehabilitation for 2 weeks. A prolonged iron deficiency resulting in decreased levels of glutamate and GABA may lead to endocrinological, neurological, and behavioral alterations. 相似文献
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A pollen-morphology study of Amaranthus spinosus, A. dubius, and their hybrids has been carried out. Three pollen types have been observed, namely (1) Type A: micrograins; (2) Type B: grains with smaller pores; and (3) Type C: grains with larger pores. Type B is characteristic of A. spinosus, Type C of A. dubius, and the micrograins of the hybrids. Pollen size range, and frequency of the various morphotypes serve to throw light on the biosystematics of the plants studied. 相似文献
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Veena Pandey I. D. Bhatt Shyamal K. Nandi 《Physiology and Molecular Biology of Plants》2021,27(2):327
Valeriana jatamansi Jones, an important medicinal herb of the Himalayan region, is an essential source of many therapeutic compounds and is traded/consumed in very high volume. The hypothesis of this study was that different seasons and light conditions may affect the content of medicinally valuable components with changes in the morpho-physiological attributes of the plant. Growing plants under suitable light conditions and harvesting of appropriate plant parts in optimum season is crucial for harnessing the full potential of the crop. Thus, the study was carried out to determine the seasonal response of V. jatamansi plants (genetically identical plants of same age) in terms of growth and phytochemical content under two different light conditions (full sunlight and 50% shade). During all seasons, growth parameters (plant height, leaf number, leaf area, relative water content, plant biomass) and the principle bioactive compounds (valerenic acid) were higher under shade conditions, while total flavonoids, tannins, phenolic compounds and antioxidant activities were higher under full sunlight conditions. HPLC analysis revealed that valerenic acid and most of the phenolic content were higher during summer season, especially in leaf part of the plant. The study suggested harvesting of V. jatamansi plants (especially leaf), during summer season to harness high quality raw material and to prevent loss of belowground parts. This strategy can be adopted by farmers for large scale cultivation of species.Supplementary InformationThe online version of this article contains supplementary material available at 10.1007/s12298-021-00944-0 相似文献
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Neurochemical Research - The present study demonstrates the epigenetic mechanisms underlying the effect of Bacoside rich extract of Bacopa monniera—a nootropic herb, on scopolamine treated... 相似文献
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Importance to know and understand diversity of Himalayan plants is increasingly recognized considering the fact that various natural and anthropogenic pressures might bring about serious influences to morphological and genetic diversity of the vegetation in the region. In this context, Valeriana jatamansi was investigated in detail, taking into account its importance in various Ayurvedic and modern medicines. Randomly selected mature plants from twenty five different populations (located between 1215 m to 2775 m asl) of V. jatamansi were analysed for their morphological attributes. Further, ISSR markers were used to detect genetic variation among 151 plants of selected 25 populations. Use of 20 primers yielded 125 reproducible polymorphic loci which were used to estimate different parameters of genetic diversity. These parameters were in turn applied to develop relationships with habitat types and altitude range. Significant variation (p < 0.05) in above ground dry weight (AGDW) and below ground dry weight (BGDW) across the populations was observed. Nei's genetic diversity index (He) ranged from 0.25 to 0.37 across the populations, with a mean of 0.31. Genetic diversity exhibited a decreasing trend with increasing altitude, and maximum diversity (He = 0.325) was observed in the range of 1201–1500 m asl. Among the different habitat conditions, highest genetic diversity (He = 0.334; Pp = 84.38) was observed in grassland habitats while minimum in mixed forest habitats (He = 0.285; Pp = 72.433). The genetic diversity (He) had significant negative relationships with AGDW, BGDW and rhizome diameter (Pearson r = −0.359, −0.424 and −0.317, respectively; p < 0.05). The genetic characterization of V. jatamansi from the western Himalaya by this study suggests influences of habitat types and the altitudinal range upon genetic diversity, and based on these proposals for conservation strategies in favour of the species are made. 相似文献
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Proteolytic enzymes of the caspase family, which reside as latent precursors in most nucleated metazoan cells, are core effectors of
apoptosis. Of them, the executioner caspases- 3 and -7 exist within the cytosol as inactive dimers and are activated by a process
called dimerization. Caspase inhibition is looked upon as a promising approach for treating multiple diseases. Though caspases
have been extensively studied in the human system, their role in eukaryotic pathogens and parasites of human hosts has not drawn
enough attention. In protein sequence analysis, caspases of blood flukes (Schistosoma spp) were revealed to have a low sequence
identity with their counterparts in human and other mammalian hosts, which encouraged us to analyse interacting domains that
participate in dimerization of caspases in the parasite and to reveal differences, if any, between the host-parasite systems.
Significant differences in the molecular surface arrangement of the dimer interfaces reveal that in schistosomal caspases only eight
out of forty dimer conformations are similar to human caspase structures. Thus, the parasite-specific dimer conformations (that are
different from caspases of the host) may emerge as potential drug targets of therapeutic value against schistosomal infections.
Three important factors namely, the size of amino acids, secondary structures and geometrical arrangement of interacting domains
influence the pattern of caspase dimer formation, which, in turn, is manifested in varied structural conformations of caspases in the
parasite and its human hosts. 相似文献
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Imteyaz Ahmad Khan Sucharita Pilli Surendranath A Ritika Rampal Sudhir Kumar Chauhan Veena Tiwari Venigalla Pratap Mouli Saurabh Kedia Baibaswata Nayak Prasenjit Das Govind K. Makharia Vineet Ahuja 《PloS one》2016,11(3)