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991.
The gene cluster composed of varicella-zoster virus (VZV) open reading frame 9 (ORF9) to ORF12 encodes four putative tegument proteins and is highly conserved in most alphaherpesviruses. In these experiments, the genes within this cluster were deleted from the VZV parent Oka (POKA) individually or in combination, and the consequences for VZV replication were evaluated with cultured cells in vitro and with human skin xenografts in SCID mice in vivo. As has been reported for ORF10, ORF11 and ORF12 were dispensable for VZV replication in melanoma and human embryonic fibroblast cells. In contrast, deletion of ORF9 was incompatible with the recovery of infectious virus. ORF9 localized to the virion tegument and formed complexes with glycoprotein E, which is an essential protein, in VZV-infected cells. Recombinants lacking ORF10 and ORF11 (POKADelta10/11), ORF11 and ORF12 (POKADelta11/12), or ORF10, ORF11 and ORF12 (POKADelta10/11/12) were viable in cultured cells. Their growth kinetics did not differ from those of POKA, and nucleocapsid formation and virion assembly were not disrupted. In addition, these deletion mutants showed no differences compared to POKA in infectivity levels for primary human tonsil T cells. Deletion of ORF12 had no effect on skin infection, whereas replication of POKADelta11, POKADelta10/11, and POKADelta11/12 was severely reduced, and no virus was recovered from skin xenografts inoculated with POKADelta10/11/12. These results indicate that with the exception of ORF9, the individual genes within the ORF9-to-ORF12 gene cluster are dispensable and can be deleted simultaneously without any apparent effect on VZV replication in vitro but that the ORF10-to-ORF12 cluster is essential for VZV virulence in skin in vivo. 相似文献
992.
Sephora Serrano Baldisera Raiane Pereira Schwengber Paulo Giliard da Silva Ferreira Ezilda Jacomassi Zilda Cristiani Gazim Simone de Melo Santana‐Gomes 《Journal of Phytopathology》2021,169(1):28-36
Pratylenchus brachyurus is a phytonematode species mostly damaging crops. It is mainly controlled by agrochemicals which are harmful to the environment and public health. Such outcomes encourage the development of research on products and/or processes to control this phytonematode and to contribute to the sustainability of agricultural systems. Thus, the aim of the current study was to assess host suitability of Achillea millefolium to P. brachyurus, as well as the nematicidal potential of its essential oil and root exudates. We conducted two experiments with two different plant species—Glycine max (soya bean) and Achillea millefolium (yarrow)—based on a 2 × 3 factorial arrangement to assess host suitability. Plants were assessed 5, 10 and 15 days after inoculation through the fuchsine acid staining technique. Based on the results, A. millefolium was an unfavourable host to this phytonematode. Therefore, it can be recommended for crop rotation and/or succession systems in small areas. We tested the nematicidal activity of the essential oil and exudates of A. millefolium at concentrations of 0, 25, 50, 100, 200, 300, 400 and 500 µg/ml in a BOD incubator at 26°C for 48 hr. The essential oil showed increasing linear regression, that is the higher was the concentration, the higher was the mortality rate. Exudates showed a quadratic behaviour (p ≤ .05), leading to 60.83% nematode mortality. Therefore, the essential oil and root exudates of A. millefolium have the potential to control P. brachyurus. The essential oil showed antagonistic properties likely because of the presence of germacrene D (39.55%), (E,E)‐α‐farnesene (25.70%) and chamazulene (8.91%). 相似文献
993.
Crass T Antes I Basekow R Bork P Buning C Christensen M Claussen H Ebeling C Ernst P Gailus-Durner V Glatting KH Gohla R Gössling F Grote K Heidtke K Herrmann A O'Keeffe S Kiesslich O Kolibal S Korbel JO Lengauer T Liebich I van der Linden M Luz H Meissner K von Mering C Mevissen HT Mewes HW Michael H Mokrejs M Müller T Pospisil H Rarey M Reich JG Schneider R Schomburg D Schulze-Kremer S Schwarzer K Sommer I Springstubbe S Suhai S Thoppae G Vingron M Warfsmann J Werner T Wetzler D Wingender E 《Bioinformatics (Oxford, England)》2004,20(2):268-270
SUMMARY: The Helmholtz Network for Bioinformatics (HNB) is a joint venture of eleven German bioinformatics research groups that offers convenient access to numerous bioinformatics resources through a single web portal. The 'Guided Solution Finder' which is available through the HNB portal helps users to locate the appropriate resources to answer their queries by employing a detailed, tree-like questionnaire. Furthermore, automated complex tool cascades ('tasks'), involving resources located on different servers, have been implemented, allowing users to perform comprehensive data analyses without the requirement of further manual intervention for data transfer and re-formatting. Currently, automated cascades for the analysis of regulatory DNA segments as well as for the prediction of protein functional properties are provided. AVAILABILITY: The HNB portal is available at http://www.hnbioinfo.de 相似文献
994.
Jinte Middeldorp Simone A. van den Berge Eleonora Aronica Dave Speijer Elly M. Hol 《PloS one》2009,4(11)
The human GFAP splice variants GFAPΔ164 and GFAPΔexon6 both result in a GFAP protein isoform with a unique out-of-frame carboxy-terminus that can be detected by the GFAP+1 antibody. We previously reported that GFAP+1 was expressed in astrocytes and in degenerating neurons in Alzheimer''s disease brains. In this study we aimed at further investigating the neuronal GFAP+1 expression and we started by affinity purifying the GFAP+1 antibody. The purified antibody resulted in a loss of neuronal GFAP+1 signal, although other antibodies directed against the amino- and carboxy-terminus of GFAPα still revealed GFAP-immunopositive neurons, as described before. With an in-depth analysis of a western blot, followed by mass spectrometry we discovered that the previously detected neuronal GFAP+1 expression was due to cross-reactivity of the antibody with neurofilament-L (NF-L). This was confirmed by double-label fluorescent immunohistochemistry and western blotting with the unpurified GFAP+1 antibody and an antibody against NF-L. Our data imply that NF-L can accumulate in some tangle-like structures in Alzheimer brains. More importantly, the purified GFAP+1 antibody clearly revealed a specific subtype of astrocytes in the adult human brain. These large astrocytes are present throughout the brain, e.g., along the subventricular zone, in the hippocampus, in the striatum and in the spinal cord of controls, Alzheimer, and Parkinson patients. The presence of a specific GFAP-isoform suggests a specialized function of these astrocytes. 相似文献
995.
With this study we estimated the changes in colour, bleaching and mortality of coral colonies from February to December 2007,
using the colour reference card method. The study was developed in the Watamu Marine Park lagoon (Kenya), bridging the local
summer when seawater temperatures were highest and coral bleaching risk was at its maximum. Seven coral genera were selected,
and their colour recorded using a colour reference card (Coral Watch card). Seven different scenarios of bleaching and mortality
were observed, varying among the coral genera and between two species in the genus Pocillopora. Twenty percent of the colonies bleached, of which 50% died. Only 15% of the coral that did not bleach died. Branching genera
had a higher bleaching incidence than massive and sub-massive genera. Pocillopora showed the highest bleaching susceptibility, followed by Acropora, and the highest level of mortality. Of the two species of Pocillopora considered in this study, P. eydouxi showed higher bleaching and mortality levels, while P. verrucosa bleached less and experienced only partial mortality. Our results evidenced different patterns of coral bleaching and mortality
which were easily and clearly detected with the colour card method during both bleaching and a post-bleaching events. 相似文献
996.
Sarah Kiefer Anne Spiess† Silke Kipper Roger Mundry‡ Christina Sommer Henrike Hultsch & Dietmar Todt 《Ethology : formerly Zeitschrift fur Tierpsychologie》2006,112(12):1217-1224
Based on the assumptions that birdsong indicates male quality and that quality is related to age, one might expect older birds to signal their age. That is, in addition to actual body condition, at least some song features should vary with age, presumably towards more complexity. We investigated this issue by comparing repertoire sizes of free‐ranging common nightingale males in their first breeding season with those of older males. Nightingales are a good model species as they are open‐ended learners, where song acquisition is not confined to an early sensitive period of learning. Moreover, nightingales develop an extraordinarily large song‐type repertoire (approx. 180 different song types per male), and differences in repertoire size among males are pronounced. We analysed repertoire characteristics of the nocturnal song of nine nightingales in their first breeding season and compared them with the songs of nine older males. The repertoire size of older males was on average 53% larger than that of yearlings. When analysing two song categories of nightingales, whistle and non‐whistle songs separately, we found similar results. Our findings show marked differences in repertoire size between age categories, suggesting that this song feature may reflect a male's age. We discuss those mechanisms that may constrain the development of larger repertoires in first‐year males. Whether repertoire sizes are crucial for female mate choice or in vocal interactions among conspecific males remains open to further investigations. 相似文献
997.
Resta N Susca FC Di Giacomo MC Stella A Bukvic N Bagnulo R Simone C Guanti G 《Journal of cellular physiology》2006,209(1):67-73
Roberts syndrome (RS) is a rare disorder characterized by tetraphocomelia and several other clinical features. Cells from RS patients exhibit characteristic premature separation of heterochromatic region of many chromosomes and abnormalities in cell cycle. Mutations in the ESCO2 gene have recently been identified in 20 RS families. We performed mutational analysis of the ESCO2 gene in two fetuses diagnosed with RS and their normal parents. In both fetuses, we identified homozygosity for the c. 745_746delGT mutation, while the non-consanguineous parents were both heterozygous for the same mutation. Considering the position of the mutation identified, we carried out qualitative and quantitative real-time ESCO2 cDNA analysis on RNA isolated from CVS-stromal cells in one fetus, amniocytes in the second fetus, and lymphocytes from the heterozygous parents. The results of this analysis showed that despite the presence of a premature termination codon (PTC) 112 nucleotides upstream of the next exon3-exon4 junction, the mutant ESCO2 mRNA was present in both fetuses, albeit at low levels, indicating a partial resistance to nonsense mediated decay (NMD). Interestingly, when cells derived from the two fetuses were treated with an inhibitor of translation, they revealed the presence of tissue and individual variability in NMD efficiency, despite the identical mutational status. The existence of such a variation in the NMD efficiency could explain the broad intrafamilial and interfamilial variability in the clinical presentation of RS patients, and in other genetic diseases where nonsense mutations are responsible for most of the mutation load. Moreover, considering that a mutated full length mRNA was produced in both fetuses, we used Western blot analysis to demonstrate the absence of the ESCO2-truncated protein in cells derived from both fetuses and in a lymphoblastoid cell line derived from the parents. 相似文献
998.
Estimating the ecological status and change of riparian zones in Andalusia assessed by multi-temporal AVHHR datasets 总被引:1,自引:0,他引:1
Following the European Commission's Water Framework Directive all surface waters in EU's Member States must reach a good status by 2015. The evaluation of this status will be partly based on ecological criteria, such as the hydro-morphological quality criteria which also evaluate the structure and condition of the riparian zone. Riparian zones with undisturbed or nearly undisturbed condition are given high-ecological status. The agri-environmental measures in the EU promote an extensive use of land to protect the farmed environment and its biodiversity. Recent studies in Andalusia and elsewhere suggest that extensification leads to riparian zones with higher ecological status compared to intensively used areas. We suggest that extensification and thus better ecological status of the riparian zone can be partly approximated by the amount of vegetation permanently present on the area. For this the so-called permanent vegetation fraction was derived from a multi-temporal advanced very high-resolution radiometer (AVHRR) dataset and was used (1) to classify the ecological status of the riparian zone into two classes, favourable and unfavourable, and (2) to assess the effect of agricultural practices on these areas. The classification was validated by field observations in the Guadalquivir river basin while detailed information on farming practices helped to assess the effect of agriculture on the riparian zone. The assessment was carried out in olive land cover because erosion control in olive cultivations is the most widely implemented measure in Andalusia. Results suggest that the remotely sensed permanent vegetation fraction is a good indicator of the favourable and unfavourable ecological status of the riparian zone. Furthermore, extensification of agricultural practices expressed in terms of increasing permanent vegetation cover was shown to have positive effect on the riparian zone as opposed to areas where no measures were implemented. 相似文献
999.
1000.
Amici M Cecarini V Pettinari A Bonfili L Angeletti M Barocci S Biagetti M Fioretti E Eleuteri AM 《Biological chemistry》2007,388(1):107-117
Aflatoxins (AF) are contaminants of improperly stored foods; they are potent genotoxic and carcinogenic compounds, exerting their effects through damage to DNA. They can also induce mutations that increase oxidative damage. The goal of this study was to evaluate the possibility that a third mechanism could be involved in the carcinogenic action of aflatoxins, namely, direct binding to key enzymes involved in the regulatory pathways of the cell cycle, thereby modulating enzyme functionality. The 20S constitutive and immunoproteasome peptidase and proteolytic activities were assayed in the presence of aflatoxins B1, G1 and M1. All three toxins activated multiple peptidase activities of the proteasome. Aflatoxin (AF) M1 was the most potent activator of proteasome activity, while the constitutive 20S proteasome was specifically stimulated by AFG1. Furthermore, the effects of AFB1 on cultured hepatoma cells were investigated and the various proteasomal activities determined with cell lysates were differently affected. Taking into account the key role of the proteasome in cellular defense against oxidative stress, the carbonyl group content and the activities of antioxidant enzymes in cell lysates were analyzed. The proapoptotic effect of AFB1 was also investigated by measuring caspase-3 activity and cellular levels of p27 and IkappaBalpha. 相似文献