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151.
C Oliveira LM Vera JF López-Olmeda JM Guzmán E Ma?anós J Ramos FJ Sánchez-Vázquez 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2009,152(2):168-175
In this paper we attempted to investigate the existence of daily fluctuations on plasma sexual steroids (17beta-estradiol, E(2) and testosterone, T) in Senegal sole (Solea senegalensis) females. We described the monthly day/night concentrations and seasonal daily rhythms in animals reared under natural photo- and thermo-period. In addition, the influence of the natural annual fluctuation of the water temperature on the plasma concentration of these steroids was investigated, using one group of Senegal sole under a natural photoperiod, but with an attenuated thermal cycle (around 17-20 degrees C) for one year. Although no significant day/night differences were detected in monthly samplings, the existence of an annual rhythm of E(2) and T (p<0.01) with an acrophase in February was revealed by COSINOR analysis. Maximum values were reached in March for both steroids (6.1+/-1.7 ng mL(-1) at mid-dark, MD and 4.0+/-0.6 ng mL(-1) at mid-light, ML for E2 and 1.4+/-0.4 ng mL(-1) at MD and 0.8+/-0.1 ng mL(-1) at ML for T) in anticipation of the spawning season (May-June). As regards seasonal daily rhythms, the presence of daily oscillations was revealed. At the spring solstice (21st March) a daily rhythm was observed for both steroids (COSINOR, p<0.01), with an acrophase at 20:00 h (E(2)) and at 21:08 h (T). In summer, autumn and winter no daily rhythms were observed due to the low steroid levels at those seasons. When Senegal sole females were submitted to an attenuated annual thermal cycle, the steroid rhythm disappeared (there was no surge in spring, as in the control group) and these fish did not spawn, despite being subjected to natural photoperiod conditions. This result underlined the importance of the natural annual fluctuation of water temperature and photoperiod on the synchronization of the spawning season and on the onset of steroidogenesis. 相似文献
152.
153.
Sabine JM de Brouwer Floris W Kraaimaat Fred CGJ Sweep Marjonne CW Creemers Timothy RDJ Radstake Antoinette IM van Laarhoven Piet LCM van Riel Andrea WM Evers 《Arthritis research & therapy》2010,12(3):R89
Introduction
Stressful events are thought to contribute to the aetiology, maintenance and exacerbation of rheumatic diseases. Given the growing interest in acute stress responses and disease, this review investigates the impact of real-life experimental psychosocial, cognitive, exercise and sensory stressors on autonomic, neuroendocrine and immune function in patients with inflammatory rheumatic diseases. 相似文献154.
Zhenya P. Yordanova Elena T. Iakimova Simona M. Cristescu Frans JM Harren Veneta M. Kapchina‐Toteva Ernst J. Woltering 《Cell biology international》2010,34(3):301-308
This work demonstrates a contribution of ethylene and NO (nitric oxide) in MP (mastoparan)‐induced cell death in the green algae Chlamydomonas reinhardtii. Following MP treatment, C. reinhardtii showed massive cell death, expressing morphological features of PCD (programmed cell death). A pharmacological approach involving combined treatments with MP and ethylene‐ and NO‐interacting compounds indicated the requirement of trace amounts of both ethylene and NO in MP‐induced cell death. By employing a carbon dioxide laser‐based photoacoustic detector to measure ethylene and a QCL (quantum cascade laser)‐based spectrometer for NO detection, simultaneous increases in the production of both ethylene and NO were observed following MP application. Our results show a tight regulation of the levels of both signalling molecules in which ethylene stimulates NO production and NO stimulates ethylene production. This suggests that, in conjunction with the elicitor, NO and ethylene cooperate and act synchronously in the mediation of MP‐induced PCD in C. reinhardtii. To the best of our knowledge, this is the first report on the functional significance of ethylene and NO in MP‐induced cell death. 相似文献
155.
Pruijn GJ 《Arthritis research & therapy》2006,8(4):110-3
Many intracellular macromolecular complexes that are involved in the production or degradation of RNAs are targeted by autoantibodies
in systemic autoimmune diseases. RNA interference (RNAi) is a recently characterized gene silencing pathway by which specific
mRNAs are either degraded or translationally suppressed. In a recent issue of Arthritis Research and Therapy, Andrew Jakymiw and colleagues reported that the enigmatic Su autoantigen complex contains key components of the RNAi machinery.
Anti-Su autoantibodies from both human patients with rheumatic diseases and a mouse model of autoimmunity recognize the endonucleolytic
Argonaute and Dicer proteins, both crucial enzymes of the RNAi pathway. These data raise the question of how the anti-Su response
is triggered. So far, it is unknown whether molecular modifications may be involved, as has been proposed for other intracellular
autoantigens. The implication of RNAi in anti-viral defence may suggest a role for virus infection in this process. 相似文献
156.
Kop EN Adriaansen J Smeets TJ Vervoordeldonk MJ van Lier RA Hamann J Tak PP 《Arthritis research & therapy》2006,8(5):R155-11
Synovial tissue of rheumatoid arthritis (RA) patients is characterised by an influx and retention of CD97-positive inflammatory
cells. The ligands of CD97, CD55, chondroitin sulfate B, and α5β1 (very late antigen [VLA]-5) are expressed abundantly in
the synovial tissue predominantly on fibroblast-like synoviocytes, endothelium, and extracellular matrix. Based upon this
expression pattern, we hypothesise CD97 expression to result in accumulation of inflammatory cells in the synovial tissue
of RA patients. To determine the therapeutic effect of blocking CD97 in an animal model of RA, collagen-induced arthritis
was induced in a total of 124 DBA/J1 mice. Treatment was started on day 21 (early disease) or on day 35 (longstanding disease)
with the blocking hamster anti-mouse CD97 monoclonal antibody (mAb) 1B2, control hamster immunoglobulin, or NaCl, applied
intraperitoneally three times a week. The paws were evaluated for clinical signs of arthritis and, in addition, examined by
radiological and histological analysis. Mice receiving 0.5 mg CD97 mAb starting from day 21 had significantly less arthritis
activity and hind paw swelling. Furthermore, joint damage and inflammation were reduced and granulocyte infiltration was decreased.
When treatment was started on day 35, CD97 mAb treatment had similar effects, albeit less pronounced. The results support
the notion that CD97 contributes to synovial inflammation and joint destruction in arthritis. 相似文献
157.
Martijn van Zanten Federico Tessadori Laurens Bossen Anton JM Peeters Paul Fransz 《Plant signaling & behavior》2010,5(12):1677-1678
Arabidopsis thaliana is widely used as a model to study chromatin compaction dynamics during development and in response to the environment. Signals such as prolonged heat treatment, low light and pathogen infestation are known to induce large-scale de-condensation of nuclear chromatin. Here we demonstrate that the response to different environments varies at the nucleosomal level. Our results show that in contrast to previous reports on heat and biotic infestation, low light intensity signaling does not alter nucleosomal occupancy, despite the marked effects of low light on global chromatin compaction.Key words: Arabidopsis, chromatin, nucleosomes, MNase IThanks to its relatively simple chromatin organization, Arabidopsis thaliana became the model of choice to study dynamics in nuclear chromatin compaction in plants.1–3 At the microscopic level, highly condensed ‘heterochromatic’ domains (chromocenters), containing compact DNA (mainly repetitive sequences), and less condensed gene-rich ‘euchromatic’ domains can be distinguished upon staining with DAPI (4′,6-diamidino-2-phenylindole). This division however, is not static and compaction changes throughout development (reviewed in ref. 4). Chromatin for example de-condensates prior to flowering5 and increases with cell differentiation during leaf maturation3 and seedling establishment.6 Vice versa, artificially induced cell de-differentiation during protoplastization, results in loosening of compact chromatin.7,8 Chromatin compaction is also influenced by various environmental signals. These include infestation by pathogenic microorganisms such as Pseudomonas syringae, light and heat signals.9–11In our recent paper, published in Plant Physiology,12 we demonstrate that a ∼90% decrease in light intensity (low light) induces a reversible reduction in global chromatin compaction. In addition, also specifically lowering the blue-light wavelengths in the spectrum, or lowering the red-to-far red (R/Fr) ratio induced a significant reduced compaction of the nuclear chromatin. This is interesting from a functional perspective because (1) these are the relevant signals perceived by plants in natural shade conditions occurring in dense-vegetations and (2) because these wavelengths are specifically detected by the light-sensitive photoreceptor proteins. Previously, we demonstrated that the R/Fr-photoreceptor Phytochrome-B (PhyB) is a positive regulator of chromatin compaction in standard light conditions.10 We now showed that PhyB also controls low light-induced chromatin organization, but that its effect depend on the genetic background of the phyb mutant under study. Likely, PhyB exerts its effects on light-mediated chromatin compaction via stabilization of CRYPTOCHROME 2 (CRY2) protein. This chromatin-associated blue light photoreceptor is a general positive regulator of low light-induced chromatin de-compaction and in addition controls chromatin compaction during floral transition.5In addition, we demonstrated that global chromatin de-compaction during floral transition and low light treatment also occurs in euchromatic domains.5,12 To study possible chromatin changes at the nucleosomal level, we performed Micrococcal Nuclease I (MNase I) analysis. No differences were observed in the nucleosomal occupancy between standard and low light conditions in DNA gels or Southern blots hybridized with different probes for repeated sequences associated to heterochromatin, and dispersed upon low light treatment (Fig. 1). This suggests that the large-scale heterochromatin (de)compaction response observed at the microscopic level under low light conditions is not necessarily accompanied by nucleosomal displacement. These results are in line with the de-condensation conditions induced by protoplastization, where no changes in H3K9Me2 or in DNA methylation (5-mC) levels were found.7 However, these results are in contrast to the results of Pecinka and colleagues,11 who demonstrated that prolonged heat stress results in heterochromatin de-condensation and loss of nucleosomes. Moreover, it is in contrast with Pavet and co-workers,9 who found reduced 5-mC levels upon infection with P. syringae. Although the results of Pecinka and colleaugues11 were obtained by real-time PCR which may be more sensitive than our Southern blots, we conclude that the response of plants to their environment at the chromatin compaction level may be tailored to the specific signal it is confronted with and that this probably can be dissected at the nucleosomal level.Open in a separate windowFigure 1MNase I analysis of low light treated plants. Southern blots with 3 different probes hybridized to DNA from Col-0 plants cultured under standard (200 µmol m−2 s−1; control) and low light (15 µmol m−2 s−1) conditions. For each part, the first two lanes represent control DNA samples (no MNase I), followed by lanes with increasing MNase I concentrations (0.02, 0.1, 0.75 and 3 units MNase I). (A) 5S rDNA probe, (B) 45S rDNA probe, (C) pAl1 probe (180 bp centromeric repeat). M = molecular weight marker. 相似文献
158.
A genomics-informed,SNP association study reveals FBLN1 and FABP4 as contributing to resistance to fleece rot in Australian Merino sheep 总被引:1,自引:0,他引:1
Wendy JM Smith Yutao Li Aaron Ingham Eliza Collis Sean M McWilliam Tom J Dixon Belinda J Norris Suzanne I Mortimer Robert J Moore Antonio Reverter 《BMC veterinary research》2010,6(1):27
Background
Fleece rot (FR) and body-strike of Merino sheep by the sheep blowfly Lucilia cuprina are major problems for the Australian wool industry, causing significant losses as a result of increased management costs coupled with reduced wool productivity and quality. In addition to direct effects on fleece quality, fleece rot is a major predisposing factor to blowfly strike on the body of sheep. In order to investigate the genetic drivers of resistance to fleece rot, we constructed a combined ovine-bovine cDNA microarray of almost 12,000 probes including 6,125 skin expressed sequence tags and 5,760 anonymous clones obtained from skin subtracted libraries derived from fleece rot resistant and susceptible animals. This microarray platform was used to profile the gene expression changes between skin samples of six resistant and six susceptible animals taken immediately before, during and after FR induction. Mixed-model equations were employed to normalize the data and 155 genes were found to be differentially expressed (DE). Ten DE genes were selected for validation using real-time PCR on independent skin samples. The genomic regions of a further 5 DE genes were surveyed to identify single nucleotide polymorphisms (SNP) that were genotyped across three populations for their associations with fleece rot resistance. 相似文献159.
Jeroen CW Rijk Ad ACM Peijnenburg Peter JM Hendriksen Johan M Van Hende Maria J Groot Michel WF Nielen 《BMC veterinary research》2010,6(1):44
Background
Within the European Union the use of growth promoting agents in animal production is prohibited. Illegal use of natural prohormones like dehydroepiandrosterone (DHEA) is hard to prove since prohormones are strongly metabolized in vivo. In the present study, we investigated the feasibility of a novel effect-based approach for monitoring abuse of DHEA. Changes in gene expression profiles were studied in livers of bull calves treated orally (PO) or intramuscularly (IM) with 1000 mg DHEA versus two control groups, using bovine 44K DNA microarrays. In contrast to controlled genomics studies, this work involved bovines purchased at the local market on three different occasions with ages ranging from 6 to 14 months, thereby reflecting the real life inter-animal variability due to differences in age, individual physiology, season and diet. 相似文献160.