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561.
Xana SPinto Alexandre Pinto Joana Ribeiro Inês Sarmento Patrícia Pessoa Leonor R. Rodrigues Lucía VzquezBen Evangelia Mavrikaki Joaquim Bernardino Lopes 《Ecology and evolution》2021,11(18):12236
While several researchers have suggested that evolution should be explored from the initial years of schooling, little information is available on effective resources to enhance elementary school students’ level of understanding of evolution by natural selection (LUENS). For the present study, we designed, implemented, and evaluated an educational activity planned for fourth graders (9 to 10 years old) to explore concepts and conceptual fields that were historically important for the discovery of natural selection. Observation field notes and students’ productions were used to analyze how the students explored the proposed activity. Additionally, an evaluation framework consisting of a test, the evaluation criteria, and the scoring process was applied in two fourth‐grade classes (N = 44) to estimate elementary school students’ LUENS before and after engaging in the activity. Our results show that our activity allowed students to link the key concepts, resulting in a significant increase of their understanding of natural selection. They also reveal that additional activities and minor fine‐tuning of the present activity are required to further support students’ learning about the concept of differential reproduction. 相似文献
562.
Mónica Martins Maria Leonor Faleiro Raúl Jorge Barros Ana Raquel Veríssimo Maria Clara Costa 《Biodegradation》2009,20(4):559-567
Biological treatment with dissimilatory sulphate-reducing bacteria has been considered the most promising alternative for
decontamination of sulphate rich effluents. These wastewaters are usually deficient in electron donors and require their external
addition to achieve complete sulphate reduction. The aim of the present study was to investigate the possibility of using
food industry wastes (a waste from the wine industry and cheese whey) as carbon sources for dissimilatory sulphate-reducing
bacteria. The results show that these wastes can be efficiently used by these bacteria provided that calcite tailing is present
as a neutralizing and buffer material. A 95 and 50 % sulphate reduction was achieved within 20 days of experiment by a consortium
of dissimilatory sulphate-reducing bacteria grown on media containing waste from the wine industry or cheese whey respectively.
Identification of the dissimilatory sulphate-reducing bacteria community using the dsr gene revealed the presence of the species Desulfovibrio fructosovorans,
Desulfovibrio aminophilus and Desulfovibrio desulfuricans. The findings of the present study emphasise the potential of using wastes from the wine industry as carbon source for dissimilatory
sulphate-reducing bacteria, combined with calcite tailing, in the development of cost effective and environmentally friendly
bioremediation processes. 相似文献
563.
The antiproliferative activity of several natural and synthetic flavonoids and some related compounds was evaluated in vitro against a cell line derived from a human cervical carcinoma (WISH cells). According to their activities, the most potent derivatives were 2'-nitroflavone (14), 2',6-dinitroflavone (15) and the n-buthyl ester of caffeic acid (29). When these compounds were tested in the presence of recombinant human interferon-alpha2b (rhIFN-alpha2b), a cytokine exhibiting an antimitogenic action on WISH cells, an additive effect on cell growth inhibition was observed. Time course studies of the antiproliferative action exerted by the active derivatives or the rhIFN-alpha2b suggested that these compounds induced cell death. 相似文献
564.
Aurelle D Guillemaud T Afonso P Morato T Wirtz P Santos RS Cancela ML 《Comptes rendus biologies》2003,326(8):771-785
Microsatellite markers have been used to study the genetic variability of rainbow wrasse (Coris julis) Mediterranean and Atlantic populations. Differentiation tests failed to reveal any significant genetic differentiation among samples from continental Portugal and the Azores, despite more than 1800 km of geographical separation. Preliminary results tended to indicate a significant genetic differentiation among Atlantic and Mediterranean samples. It also supported the specific status of Cape Verde populations (Coris atlantica). We compare these results with previous mtDNA analyses and propose a biogeographic scenario that could explain our results. 相似文献
565.
Amanpreet K. Cheema Leonor Sarria Mina Bekheit Fanny Collado Eloy Almenar-Pérez Eva Martín-Martínez Jose Alegre Jesus Castro-Marrero Mary A. Fletcher Nancy G. Klimas Elisa Oltra Lubov Nathanson 《Journal of cellular and molecular medicine》2020,24(10):5865-5877
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a multisystem illness characterized by medically unexplained debilitating fatigue with suggested altered immunological state. Our study aimed to explore peripheral blood mononuclear cells (PBMCs) for microRNAs (miRNAs) expression in ME/CFS subjects under an exercise challenge. The findings highlight the immune response and inflammation links to differential miRNA expression in ME/CFS. The present study is particularly important in being the first to uncover the differences that exist in miRNA expression patterns in males and females with ME/CFS in response to exercise. This provides new evidence for the understanding of differential miRNA expression patterns and post-exertional malaise in ME/CFS. We also report miRNA expression pattern differences associating with the nutritional status in individuals with ME/CFS, highlighting the effect of subjects' metabolic state on molecular changes to be considered in clinical research within the NINDS/CDC ME/CFS Common Data Elements. The identification of gender-based miRNAs importantly provides new insights into gender-specific ME/CFS susceptibility and demands exploration of sex-suited ME/CFS therapeutics. 相似文献
566.
Leonor Cruzeiro 《Journal of biological physics》2009,35(1):43-55
The current status of the Davydov/Scott model for energy transfer in proteins is reviewed. After a brief introduction to the
theoretical framework and to the basic results, the problems of finite temperature dynamics and of the full quantum and mixed
quantum-classical approximations are described, as well as recent results obtained within each of these approximations. A
short survey of experimental evidence in support of the Davydov/Scott model is made and absorption spectra are calculated
that show the same temperature dependence as that measured in crystalline acetanilide. Future applications of the Davydov/Scott
model to protein folding and function and to misfolding diseases are outlined. 相似文献
567.
The spontaneous activity of locus coeruleus (LC) noradrenergic neurons was assessed by single unit recording in adult recovered rats undernourished at perinatal age as compared with wellnourished animals. Locus coeruleus activity, measured by the firing rate of noradrenergic neurons and the number of spontaneously active cells/track was significantly higher in deprived rats than in controls. In addition, dose-response curves for the inhibitory LC activity of clonidine showed a shift to the right in deprived animals indicating a subsensitivity of alpha2-adrenergic autoreceptors. This fact suggests an alteration in the negative feedback mechanism mediated by somatodentritic alpha2 autoreceptors that modulate the activity of LC neurons, and may account for the behavioral alterations attributed to early undernutrition. Repeated desipramine (DMI) administration to deprived rats reduced LC activity to values comparable to controls, which were not affected after a similar treatment. These data extend to previous reports on long-lasting or permanent plastic changes in the CNS induced by early undernutrition, which may be reverted by pharmacological manipulations. In addition, these results support the hypothesis that alterations induced by early undernutrition are in the same direction as and resemble those described for patients with panic disorders. Furthermore, together with behavioral alterations and selective anxiolytic effect of DMI and other drugs with antipanic effects described in early malnourished rats, the present data support the proposal that perinatally deprived rats may be a useful model for screening drugs with potential antipanic activity. 相似文献
568.
Pedro Costa-Nunes Teresa Ribeiro Margarida Delgado Leonor Morais-Cecílio Neil Jones Wanda Viegas 《Génome》2005,48(5):895-904
'Lindstr?m' wheat (AABBDD+rye B chromosomes) was used to study the effects of alien chromatin introgressed into a wheat genetic background, subjecting the wheat genome to a new and transient allopolyploidisation episode. Using this experimental material, we have previously demonstrated that no large-scale chromosomal translocations occurred as a result of the genomic constitution of the addition line. However, we have shown that the presence of a number of rye B chromosomes is associated with changes in the interphase organization and expression patterns of wheat rDNA loci. We have now extended our studies to focus on a further characterization of 'Lindstr?m' 5S rDNA loci and also on high molecular weight glutenin subunit (HMW-GS) patterns. In the process, we have uncovered an unusually large variant of the 5S rDNA locus on wheat chromosome 1B (not to be confused with rye B chromosomes) and 2 novel HMW glutenin y-type alleles. These changes are not directly related to variation in rye B chromosome number in the present material, but the fact that a new, and still segregating, 1Dy HMW-GS gene was identified indicates a recent timescale for its origin. Strikingly, the 'Lindstr?m' 5S rDNA 1B locus integrates a unit sharing 94% homology with a rye 5S rDNA sequence, suggesting the possibility that the wheat locus was colonized by highly homologous rye sequences during the breeding of 'Lindstr?m', when the rye and wheat genomes were together, albeit briefly, in the same nucleus. 相似文献
569.
570.