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61.
Letizia Riggio Bevilacqua 《Plant biosystems》2013,147(5):347-352
Abstract Studies on root apical meristem. VII. Activities of some enzymes of glycolysis, of the Krebs cycle and of the pentose phosphate cycle. — The enzymes assayed are: aldolase, glyceraldheyde-3-phosphate: NAD oxidoreductase, triosephosphate isomerase, fumarate hydratase, aconitate hydratase, glucose-6-phosphate: NADP oxidoreductase, 6-phosphogluconate: NADP oxidoreductase. The determinations were made on pea roots (Pisum sativum cv. Alaska) which were obtained by germinating seeds on moist vermiculite, in the dark, at 25° C, either for 2 or 7 days. In both cases samples were collected from the meristematic zone (0-2 mm from the apex) and from the extending zone (2-4 mm from the apex). All the enzymes determined are present both in the meristematic and in the extending zone of the root. If referred to a fresh weight basis, their activities are always greater in the meristem; if referred to a dry weight or to a protein basis, the values in the meristematic zone are nearly equal to, or higher than those in the extending zone. With respect to the development of the cell in the root from the meristematic to the vacuolated state, the present results indicate that the change in volume is accompanied by increases is the enzymes tested. 相似文献
62.
Alcohol consumption and alcohol problems after bariatric surgery in the swedish obese subjects study
63.
Andrea Bolognesi Letizia Polito Fabiola Olivieri Paola Valbonesi Luigi Barbieri M. Giulia Battelli M. Vittoria Carusi Eugenio Benvenuto Francesca Del Vecchio Blanco Antimo Di Maro Augusto Parente Mario Di Loreto Fiorenzo Stirpe 《Planta》1997,203(4):422-429
New single-chain (type 1) ribosome-inactivating proteins (RIPs) were isolated from the seeds of Basella rubra L. (two proteins) and from the leaves of Bougainvillea spectabilis Willd. (one protein). These RIPs inhibit protein synthesis both in a cell-free system, with an IC50 (concentration causing 50% inhibition) in the 10−10 M range, and by various cell lines, with IC50s in the 10−8–10−6 M range. All three RIPs released adenine not only from rat liver ribosomes but also from Escherichia coli rRNA, polyadenylic acid, herring sperm DNA, and artichoke mottled crinkle virus (AMCV) genomic RNA, thus being polynucleotide:adenosine
glycosidases. The proteins from Basella rubra had toxicity to mice similar to that of most type 1 RIPs (Barbieri et al., 1993, Biochim Biophys Acta 1154: 237–282) with
an LD50 (concentration that is 50% lethal) ≤ 8 mg · kg−1 body weight, whilst the RIP from Bougainvillea spectabilis had an LD50 >32 mg · kg−1. The N-terminal sequence of the two RIPs from Basella rubra had 80–93% identity, whereas it differed from the sequence of the RIP from Bougainvillea spectabilis. When tested with antibodies against various RIPs, the RIPs from Basella gave some cross-reactivity with sera against dianthin 32, and weak cross-reactivity with momordin I and momorcochin-S, whilst
the RIP from Bougainvillea did not cross-react with any antiserum tested. An RIP from Basella rubra and one from Bougainvillea spectabilis were tested for antiviral activity, and both inhibited infection of Nicotiana benthamiana by AMCV.
Received: 5 March 1997 / Accepted: 27 May 1997 相似文献
64.
Giovanni Romeo 《Human genetics》1977,39(3):261-276
Summary In four of the five autosomal dominant porphyrias four different partial enzymatic defects of the porphyrin biosynthetic pathway have been discovered in the last few years. With the exception of protoporphyria, the residual enzymatic activity in carriers of these defects is approximately equal to 50% of that found in controls. In each case the pattern of excretion of porphyrin and/or porphyrin precursors reflects the site of the partial metabolic block. There are indications, at least in intermittent acute porphyria, that the degree of penetrance of the disorder varies according to the level of phenotypic expression, being highest for the enzyme deficiency, lower for the excretion of precursors and lowest for the clinical symptoms. It is proposed that environmental factors, and probably also gene interaction, are the cause of the different degrees of penetrance.On leave from the University of Naples, Italy 相似文献
65.
Madrigano J Baccarelli A Mittleman MA Sparrow D Vokonas PS Tarantini L Schwartz J 《Epigenetics》2012,7(1):63-70
DNA methylation has been associated with age-related disease. Intra-individual changes in gene-specific DNA methylation over time in a community-based cohort has not been well described. We estimated the change in DNA methylation due to aging for nine genes in an elderly, community-dwelling cohort of men. Seven hundred and eighty four men from the Veterans Administration Normative Aging Study who were living in metropolitan Boston from 1999-2009 donated a blood sample for DNA methylation analysis at clinical examinations repeated at approximately 3-5 year intervals. We used mixed effects regression models. Aging was significantly associated with decreased methylation of GCR, iNOS and TLR2 and with increased methylation of IFNγ, F3, CRAT and OGG. Obstructive pulmonary disease at baseline modified the effect of aging on methylation of IFNγ (interaction p = 0.04). For participants who had obstructive pulmonary disease at their baseline visit, the rate of change of methylation of IFNγ was -0.05% 5-methyl-cytosine (5-mC) per year (95% CI: -0.22, 0.13), but was 0.14% 5-mC per year (95% CI: 0.05, 0.24) for those without this condition. Models with random slopes indicated significant heterogeneity in the effect of aging on methylation of GCR, iNOS and OGG. These findings suggest that DNA methylation may reflect differential biological aging. 相似文献
66.
Ivana A. Stojkovic Ulrika Ericson Gull Rukh Martin Riddestr?le Stefano Romeo Marju Orho-Melander 《Genes & nutrition》2014,9(2)
The Ile148Met (rs738409, G-allele) in the patatin-like phospholipase domain-containing protein 3 gene (PNPLA3) associates with liver fat content and may lead to loss-of-function (hydrolysis) or gain-of-function (CoA-dependent lysophosphatidic acid acyltransferase) defects. PNPLA3 is up-regulated by dietary carbohydrates, and interactions between rs738409 and carbohydrates, and sugar and ω6:ω3-polyunsaturated fatty acid (PUFA) ratio on hepatic fat accumulation have been reported. We examined interaction between rs738409 and overweight, and between rs738409 and dietary intakes (carbohydrates, sucrose and ω6:ω3-PUFA ratio), on fasting triglyceride levels. From the Malmo Diet and Cancer Study-Cardiovascular Cohort, 4,827 individuals without diabetes aged 58 ± 6 years, 2,346 with BMI ≤ 25 kg/m2 and 2,478 with BMI > 25 kg/m2, were included in cross-sectional analyses. Dietary data were collected by a modified diet history method. Overweight modified the association between rs738409 and fasting triglyceride levels (Pinteraction = 0.003). G-allele associated with lower triglycerides only among overweight individuals (P = 0.01). Nominally, significant interaction on triglyceride levels was observed between rs738409 and sucrose among normal-weight individuals (Pinteraction = 0.03). G-allele associated with lower triglycerides among overweight individuals in the lowest tertiles of carbohydrate and ω6:ω3-PUFA ratio (P = 0.04 and P = 0.001) and with higher triglycerides among normal-weight individuals in the highest tertile of sucrose (P = 0.001). We conclude that overweight and dietary sucrose may modify the association between rs738409 and fasting triglyceride levels.
Electronic supplementary material
The online version of this article (doi:10.1007/s12263-014-0388-4) contains supplementary material, which is available to authorized users. 相似文献67.
Gabriele Losi Letizia Mariotti Giorgio Carmignoto 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2014,369(1654)
GABAergic interneurons represent a minority of all cortical neurons and yet they efficiently control neural network activities in all brain areas. In parallel, glial cell astrocytes exert a broad control of brain tissue homeostasis and metabolism, modulate synaptic transmission and contribute to brain information processing in a dynamic interaction with neurons that is finely regulated in time and space. As most studies have focused on glutamatergic neurons and excitatory transmission, our knowledge of functional interactions between GABAergic interneurons and astrocytes is largely defective. Here, we critically discuss the currently available literature that hints at a potential relevance of this specific signalling in brain function. Astrocytes can respond to GABA through different mechanisms that include GABA receptors and transporters. GABA-activated astrocytes can, in turn, modulate local neuronal activity by releasing gliotransmitters including glutamate and ATP. In addition, astrocyte activation by different signals can modulate GABAergic neurotransmission. Full clarification of the reciprocal signalling between different GABAergic interneurons and astrocytes will improve our understanding of brain network complexity and has the potential to unveil novel therapeutic strategies for brain disorders. 相似文献
68.
The nucleotide sequences of the Escherichia coli genome between the glycogen biosynthetic genes glgB and glgC, and 1170 bp of DNA which follows glgA have been determined. The region between glgB and glgC contains an open reading frame (ORF) of 1521 bp which we call glgX. This ORF is capable of coding for an Mr 56 684 protein. The deduced amino acid (aa) sequence for the putative product shows significant similarity to the E. coli glycogen branching enzyme, and to several different glucan hydrolases and transferases. The regions of sequence similarity include residues which have been reported to be involved in substrate binding and catalysis by taka-amylase. This suggests that the proposed product may catalyze hydrolysis or glycosyltransferase reactions. The cloned region which follows glgA contains an incomplete ORF (1149 bp), glgY, which appears to encode 383 aa of the N terminus of glycogen phosphorylase, based upon sequence similarity with the enzyme from rabbit muscle (47% identical aa residues) and with maltodextrin phosphorylase from E. coli (37% identical aa residues). Results suggest that neither ORF is required for glycogen biosynthesis. The localization of glycogen biosynthetic and degradative genes together in a cluster may facilitate the regulation of these systems in vivo. 相似文献
69.
Cecilia Noccioli Letizia Meini Maria Cecilia Loi Donatella Potenza Luisa Pistelli 《Phytochemistry letters》2011,4(3):342-344
The aerial parts of Genista pichisermolliana Valsecchi (Fabaceae), an endemic plant of Sardinia, were extracted in Soxhlet apparatus and purified by several chromatographic methods. The new compound alpinumisoflavone 4′-O-glucopyranoside (6) was isolated together with nineteen flavonoids, p-coumaric methylester and d-pinitol, while no alkaloids were detected. All the chemical structures were elucidated by spectroscopic analysis. Since flavonoids represent the main constituents of this plant, the total flavonoid content was determined according to the Italian Pharmacopoeia IX Ed. method. 相似文献
70.
Bloom Syndrome and Maternal Uniparental Disomy for Chromosome 15 总被引:3,自引:1,他引:3
Trevor Woodage Madhuri Prasad Joanne W. Dixon Roslyn E. Selby Dennis R. Romain Letizia M. Columbano-Green David Graham Peter K. Rogan James R. Seip Arabella Smith Ronald J. Trent 《American journal of human genetics》1994,55(1):74-80
Bloom syndrome (BS) is an autosomal recessive disorder characterized by increases in the frequency of sister-chromatid exchange and in the incidence of malignancy. Chromosome-transfer studies have shown the BS locus to map to chromosome 15q. This report describes a subject with features of both BS and Prader-Willi syndrome (PWS). Molecular analysis showed maternal uniparental disomy for chromosome 15. Meiotic recombination between the two disomic chromosomes 15 has resulted in heterodisomy for proximal 15q and isodisomy for distal 15q. In this individual BS is probably due to homozygosity for a gene that is telomeric to D15S95 (15q25), rather than to genetic imprinting, the mechanism responsible for the development of PWS. This report represents the first application of disomy analysis to the regional localization of a disease gene. This strategy promises to be useful in the genetic mapping of other uncommon autosomal recessive conditions. 相似文献