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81.
Laetitia Mathon Virginie Marques Stéphanie Manel Camille Albouy Marco Andrello Emilie Boulanger Julie Deter Régis Hocdé Fabien Leprieur Tom B. Letessier Nicolas Loiseau Eva Maire Alice Valentini Laurent Vigliola Florian Baletaud Sandra Bessudo Tony Dejean Nadia Faure Pierre-Edouard Guerin Meret Jucker Jean-Baptiste Juhel Kadarusman Andrea Polanco F. Laurent Pouyaud Dario Schwörer Kirsten F. Thompson Marc Troussellier Hagi Yulia Sugeha Laure Velez Xiaowei Zhang Wenjun Zhong Loïc Pellissier David Mouillot 《Global Ecology and Biogeography》2023,32(8):1336-1352
Aim
Coastal fishes have a fundamental role in marine ecosystem functioning and contributions to people, but face increasing threats due to climate change, habitat degradation and overexploitation. The extent to which human pressures are impacting coastal fish biodiversity in comparison with geographic and environmental factors at large spatial scale is still under scrutiny. Here, we took advantage of environmental DNA (eDNA) metabarcoding to investigate the relationship between fish biodiversity, including taxonomic and genetic components, and environmental but also socio-economic factors.Location
Tropical, temperate and polar coastal areas.Time period
Present day.Major taxa studied
Marine fishes.Methods
We analysed fish eDNA in 263 stations (samples) in 68 sites distributed across polar, temperate and tropical regions. We modelled the effect of environmental, geographic and socio-economic factors on α- and β-diversity. We then computed the partial effect of each factor on several fish biodiversity components using taxonomic molecular units (MOTU) and genetic sequences. We also investigated the relationship between fish genetic α- and β-diversity measured from our barcodes, and phylogenetic but also functional diversity.Results
We show that fish eDNA MOTU and sequence α- and β-diversity have the strongest correlation with environmental factors on coastal ecosystems worldwide. However, our models also reveal a negative correlation between biodiversity and human dependence on marine ecosystems. In areas with high dependence, diversity of all fish, cryptobenthic fish and large fish MOTUs declined steeply. Finally, we show that a sequence diversity index, accounting for genetic distance between pairs of MOTUs, within and between communities, is a reliable proxy of phylogenetic and functional diversity.Main conclusions
Together, our results demonstrate that short eDNA sequences can be used to assess climate and direct human impacts on marine biodiversity at large scale in the Anthropocene and can further be extended to investigate biodiversity in its phylogenetic and functional dimensions. 相似文献82.
Paul M. Rowe William T. Link Charlene P. Osborn Harold Gainer R. Wayne Albers 《Journal of neurochemistry》1991,57(3):1088-1090
The distributions of alpha-subunit isoforms of the Na+,K(+)-ATPase in rat pituitary were determined by immunoblotting and immunohistochemistry. Immunoreactivity for all three forms is present in the neural lobe, whereas the anterior lobe contains only alpha 1 and alpha 2. Most areas of the intermediate lobe exhibit faint immunoreactivity for only alpha 1, but thin strands of cells which stain strongly for all three isoforms are also present in this lobe. The previously reported ouabain inhibitable Na+,K(+)-ATPase activity in the neural lobe is consistent with the presence of both alpha 2 and alpha 3 subunits. 相似文献
83.
Sircar M Bradfield PF Aurrand-Lions M Fish RJ Alcaide P Yang L Newton G Lamont D Sehrawat S Mayadas T Liang TW Parkos CA Imhof BA Luscinskas FW 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(9):5879-5887
Endothelial cell junctional adhesion molecule (JAM)-C has been proposed to regulate neutrophil migration. In the current study, we used function-blocking mAbs against human JAM-C to determine its role in human leukocyte adhesion and transendothelial cell migration under flow conditions. JAM-C surface expression in HUVEC was uniformly low, and treatment with inflammatory cytokines TNF-alpha, IL-1beta, or LPS did not increase its surface expression as assessed by FACS analysis. By immunofluorescence microscopy, JAM-C staining showed sparse localization to cell-cell junctions on resting or cytokine-activated HUVEC. Surprisingly, staining of detergent-permeabilized HUVEC revealed a large intracellular pool of JAM-C that showed little colocalization with von Willebrand factor. Adhesion studies in an in vitro flow model showed that functional blocking JAM-C mAb alone had no inhibitory effect on polymorphonuclear leukocyte (PMN) adhesion or transmigration, whereas mAb to ICAM-1 significantly reduced transmigration. Interestingly, JAM-C-blocking mAbs synergized with a combination of PECAM-1, ICAM-1, and CD99-blocking mAbs to inhibit PMN transmigration. Overexpression of JAM-C by infection with a lentivirus JAM-C GFP fusion protein did not increase adhesion or extent of transmigration of PMN or evoke a role for JAM-C in transendothelial migration. These data suggest that JAM-C has a minimal role, if any, in PMN transmigration in this model and that ICAM-1 is the preferred endothelial-expressed ligand for PMN beta(2) integrins during transendothelial migration. 相似文献
84.
Kadlcik V Sicard-Roselli C Mattioli TA Kodicek M Houee-Levin C 《Free radical biology & medicine》2004,37(6):881-891
Amyloid beta peptide (Abeta) is a 39 to 43 amino-acid-long peptide implicated in Alzheimer's disease. One of its mechanisms of toxicity is related to its redox properties. Therefore we studied its one electron oxidation using azide free radicals produced in gamma and pulse radiolysis, and compared the results with those obtained with the reverse sequence Abeta(40-1). HPLC analysis combined with absorption, fluorescence, Raman spectroscopy, and MALDI-TOF MS were used for product identification. Met35 was shown to be the target in Abeta(1-40); oxidation leads to a major compound that is Abeta with methionine sulfoxide. Similarly, oxidation of fragment Abeta(29-40) also leads to methionine sulfoxide. For Abeta(40-1), Met35 is not reactive and Tyr10 is the target of azide radicals. The major products are peptide dimer linked by dityrosine and trimer. The lowering of the one-electron reduction potential of the MetS+/Met couple, which was proposed, is in agreement with our findings. To our knowledge, this is the first time that such a drastic effect of the primary sequence is observed in a small peptide. In addition, it is also the first experimental demonstration of the sensitivity of the one-electron reduction potential of methionine on neighboring groups. 相似文献
85.
Human cells, including fibroblast strains that have been immortalized by telomerase, are much more resistant to transformation than rodent cells. Most of the experimental evidence suggests that transformation of human fibroblasts requires inactivation of both the retinoblastoma (pRb) and p53 tumor suppressors as well as the addition of one or more dominant oncogenes. By starting with strains of primary fibroblast (Leiden and Q34 cells) that are genetically deficient for p16INK4a, we have been able to generate anchorage independent colonies simply by addition of telomerase (hTERT) and either Ras or Myc. Importantly, the transformed cells appear to retain pRb and p53 functions and are essentially diploid. Whereas Leiden cells expressing the individual oncogenes did not form tumors in mice, the combination of hTERT, Myc and Ras enabled them to become tumorigenic, albeit at a frequency suggestive of an additional genetic event. Significantly, we have obtained karyotypically stable tumors without the need to use DNA tumor virus oncoproteins and without deliberate ablation of p53. 相似文献
86.
Wahlroos Tony Susi Petri Solovyev Andrej Dorokhov Yurii Morozov Sergeyi Atabekov Josif Korpela Timo 《Molecular breeding : new strategies in plant improvement》2005,14(4):455-462
An approach that enables the increase of the quantity of a specific amino acid in crop plants is reported. Oleosin gene from Arabidopsis thaliana or 30K movement protein gene of Tobacco mosaic virus (TMV; genus Tobamovirus) were cloned under the control of napin or hybrid promoters, and in fusion to synthetic poly-histidine (poly-His) sequences for transformation into spring turnip rape (Brassica rapa subsp. oleifera; synonym to B. campestris). The most stable expression cassettes for the poly-His production prior to the plant transformation were selected by analyzing the protein expression in in vitro translation and in transient plant expression systems using GFP as marker. Expression of the poly-His-constructs in transgenic Brassica rapa plants was analyzed using dot and western blotting and PCR. The constructs were stably expressed in the third generation of the transgenic plant lines. Histidine content was measured from the seeds of the transgenic plants, and some plant lines had more than 20% increase in histidine content compared to wild type. The methodology may be widely applicable to increase the content of any amino acid in crop plants including those encoded by rare codons. 相似文献
87.
88.
Jennifer C. Perry Locke Rowe 《Proceedings. Biological sciences / The Royal Society》2010,277(1700):3639-3647
Sexually selected male ejaculate traits are expected to depend on the resource state of males. Theory predicts that males in good condition will produce larger ejaculates, but that ejaculate composition will depend on the relative production costs of ejaculate components and the risk of sperm competition experienced by low- and high-condition males. Under some conditions, when low condition leads to poorer performance in sperm competition, males in low condition may produce ejaculates with higher sperm content relative to their total ejaculate and may even transfer more sperm than high-condition males in an absolute sense. Previous studies in insects have shown that males in good condition transfer larger ejaculates or more sperm, but it has not been clear whether increased sperm content represents a shift in allocation or simply a larger ejaculate, and thus the condition dependence of ejaculate composition has been largely untested. We examined condition dependence in ejaculate by manipulating adult male condition in a ladybird beetle (Adalia bipunctata) in which males transfer three distinct ejaculate components during mating: sperm, non-sperm ejaculate retained within the female reproductive tract, and a spermatophore capsule that females eject and ingest following mating. We found that high condition males indeed transferred larger ejaculates, potentially achieved by an increased rate of ejaculate transfer, and allocated less to sperm compared with low-condition males. Low-condition males transferred ejaculates with absolutely and proportionally more sperm. This study provides the first experimental evidence for a condition-dependent shift in ejaculate composition. 相似文献
89.
Chemotherapy and zoledronate sensitize solid tumour cells to Vγ9Vδ2 T cell cytotoxicity 总被引:1,自引:0,他引:1
Combinations of cellular immune-based therapies with chemotherapy and other antitumour agents may be of significant clinical
benefit in the treatment of many forms of cancer. Gamma delta (γδ) T cells are of particular interest for use in such combined
therapies due to their potent antitumour cytotoxicity and relative ease of generation in vitro. Here, we demonstrate high
levels of cytotoxicity against solid tumour-derived cell lines with combination treatment utilizing Vγ9Vδ2 T cells, chemotherapeutic
agents and the bisphosphonate, zoledronate. Pre-treatment with low concentrations of chemotherapeutic agents or zoledronate
sensitized tumour cells to rapid killing by Vγ9Vδ2 T cells with levels of cytotoxicity approaching 90%. In addition, zoledronate
enhanced the chemotherapy-induced sensitization of tumour cells to Vγ9Vδ2 T cell cytotoxicity resulting in almost 100% lysis
of tumour targets in some cases. Vγ9Vδ2 T cell cytotoxicity was mediated by perforin following TCR-dependent and isoprenoid-mediated
recognition of tumour cells. Production of IFN-γ by Vγ9Vδ2 T cells was also induced after exposure to sensitized targets.
We conclude that administration of Vγ9Vδ2 T cells at suitable intervals after chemotherapy and zoledronate may substantially
increase antitumour activities in a range of malignancies.
Financial
support and conflicts of interest: This study was supported by grants from Medinet (Japan), and Suncorp Metway and Gallipoli Research Foundation (Australia).
No financial or commercial interests arise from this study. Informed consent: This study was approved by Human Research Ethics Committees of the University of Queensland and Greenslopes Private Hospital
and informed consent was obtained from all subjects. 相似文献
90.
Engelborghs S Maertens K Vloeberghs E Aerts T Somers N Mariën P De Deyn PP 《Neurochemistry international》2006,48(4):286-295
To improve clinical, neuropsychological and behavioural characterisation of the cerebrospinal fluid (CSF) biomarkers beta-amyloid((1-42)) protein (Abeta42), protein tau (tau) and tau phosphorylated at threonine 181 (P-tau181) across diagnostic dementia categories, a prospective study was set up. Patients with probable Alzheimer's disease (AD) (n=201), AD with cerebrovascular disease (CVD) (AD+CVD) (n=33), frontotemporal dementia (FTD) (n=27), dementia with Lewy bodies (DLB) (n=22) and healthy controls (n=148) were included. All patients underwent neuropsychological examination and behavioural assessment by means of a battery of behavioural assessment scales. CSF was obtained by lumbar puncture and levels of Abeta42, tau and P-tau181 were determined with commercially available ELISA kits. Negative correlations between CSF Abeta42 levels and aggressiveness (Spearman: r=-0.223; p=0.002) and positive correlations with age at inclusion (r=0.195; p=0.006), age at onset (r=0.205; p=0.003) and MMSE scores (r=0.198; p=0.005) were found in AD. In AD+CVD, CSF Abeta42 levels were correlated with MMSE (r=0.482; p=0.006), Hierarchic Dementia Scale (r=0.503; p=0.017) and Boston Naming Test (r=0.516; p=0.012) scores. In controls, age was positively correlated with CSF tau (r=0.465; p<0.001) and P-tau181 levels (r=0.312; p<0.001). CSF tau and P-tau181 levels correlated significantly in all groups, whereas CSF Abeta42 correlated with tau and P-tau181 levels in healthy controls only. Negative correlations between CSF Abeta42 levels and aggressiveness were found in AD patients. CSF Abeta42 seems to be a stage marker for AD (+/-CVD) given the positive correlations with neuropsychological test results suggesting that CSF Abeta42 might be of help for monitoring disease progression. Different correlations between age and CSF biomarker levels were obtained in healthy controls compared to AD patients, indicating that AD-induced pathophysiological processes change age-dependent regulation of CSF biomarker levels. 相似文献