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951.
Manal Abd El Mohsen Joanne Marks Gunter Kuhnle Catherine Rice-Evans Kevin Moore Glenn Gibson 《Free radical research》2013,47(12):1329-1340
Citrus flavonoids have been investigated for their biological activity, with both anti-inflammatory and -carcinogenic effects being reported. However, little information is known on the bioavailability of these compounds in vivo. The objectives of this study were to determine the tissue distribution of naringenin after gastric gavage of [3H]-naringenin to rats. Unlabelled naringenin was also used to quantify the levels of naringenin and its major metabolites in tissues and eliminated in the urine and faeces. Significant radioactivity was detected in the plasma as well as all tissues examined 2?h post-gavage. After 18?h, higher levels of radioactivity were retained in plasma and tissues (55% of the administered radioactivity). Investigation of the nature of metabolites, using unlabelled naringenin, revealed that the glucuronides were the major components in plasma, tissues and urine, in addition to the colonic metabolite 3-(4-hydroxyphenyl) propionic acid, detected in the urine. The aglycone was the form extensively retained in tissues after 18?h post-gavage. Total identified metabolites detected after 18?h in most tissues were only 1–5% of the levels detected after 2?h. However, the brain, lungs and heart retained 27, 20 and 11%, respectively, relative to the total metabolites detected at 2?h. While radioactive detection suggests increased levels of breakdown products of naringenin after 18?h versus 2?h, the products identified using unlabelled naringenin are not consistent with this, suggesting that a predominant proportion of the naringenin breakdown products at 18?h are retained as smaller decomposition molecules which cannot yet be identified. 相似文献
952.
Beatriz Sanz-Bernardo Ismar R. Haga Najith Wijesiriwardana Sanjay Basu Will Larner Adriana V. Diaz Zoë Langlands Eric Denison Joanne Stoner Mia White Christopher Sanders Philippa C. Hawes Anthony J. Wilson John Atkinson Carrie Batten Luke Alphey Karin E. Darpel Simon Gubbins Philippa M. Beard 《Journal of virology》2021,95(9)
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Nightmares and sleep disturbances are thought to play a key role in the development of posttrauma problems. Research efforts have increased in an attempt to understand this association. The present study examined differences in nightmare characteristics, related psychopathology, treatment outcome, and trauma history among trauma-exposed individuals whose nightmares began before a traumatic event and those whose nightmares began after a traumatic event, while controlling for posttraumatic stress disorder status. Individuals whose nightmares began following a trauma experienced more depression and posttraumatic stress symptoms and poorer sleep quality, reported a higher number of traumatic events, and were more likely to report nightmares replicative of or similar to the trauma than those whose nightmares began before the trauma. No other between-groups differences were found for nightmare characteristics or response to treatment. This study is an important step in understanding the nature of nightmares and their relationship to traumatic events and consequences, but additional research is warranted. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Background aimsOligodendrocyte precursor cells (OPC) hold promise as a cellular therapy for demyelinating diseases. The feasibility of using OPC-based therapies in humans depends upon a reliable, readily available source. We have previously described the isolation, expansion and characterization of oligodendrocyte-like cells from fresh human umbilical cord blood (UCB). We now describe the isolation and expansion of OPC from thawed, cryopreserved UCBMethodsWe thawed cryopreserved UCB units employing a standard clinical protocol, then isolated and plated mononuclear cells under previously established culture conditions. All OPC cultures were trypsinized at 21 days, counted, then characterized by flow cytometry after fixation, permeablization and labeling with the following antibodies: anti-oligodendrocyte marker 4 (O4), anti-oligodendrocyte marker 1 (O1) and anti-myelin basic protein (MBP). OPC were also placed in co-culture with shiverer mouse neuronal cells then stained in situ for beta tubulin III (BT3) and MBP as a functional assay of myelination.ResultsThe average OPC yield per cryopreserved UCB unit was 64% of that seen with fresh UCB. On flow cytometric analysis, 74% of thawed UCB units yielded cells with an O4-expression level of at least 20% of total events, compared with 95% of fresh UCB units. We observed myelination of shiverer neurons in our functional assay, which could be used as a potency assay for release of OPC cells in phase I human clinical trials.ConclusionsOur results demonstrate that OPC can be derived reliably from thawed, cryopreserved UCB units, and support the feasibility of using these cells in human clinical trials. 相似文献
959.
Callahan LF Cleveland RJ Shreffler J Schwartz TA Schoster B Randolph R Renner JB Jordan JM 《Arthritis research & therapy》2011,13(5):R169
Introduction
The purpose of this study was to examine data from the Johnston County Osteoarthritis (OA) Project for independent associations of educational attainment, occupation and community poverty with tibiofemoral knee OA. 相似文献960.
Nelson AE Shi XA Schwartz TA Chen JC Renner JB Caldwell KL Helmick CG Jordan JM 《Arthritis research & therapy》2011,13(2):R37