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CD40 ligation prevents onset of tolerogenic properties in human dendritic cells treated with CTLA-4-Ig 总被引:1,自引:0,他引:1
Vacca C Fallarino F Perruccio K Orabona C Bianchi R Gizzi S Velardi A Fioretti MC Puccetti P Grohmann U 《Microbes and infection / Institut Pasteur》2005,7(7-8):1040-1048
The synthetic immunomodulator cytotoxic T lymphocyte antigen 4-Ig (CTLA-4-Ig) initiates effects in human monocyte-derived dendritic cells (DC) that rely on immunosuppressive tryptophan catabolism. However, it is unable to induce suppressive properties in DC matured by CD40 engagement. Thus, CD40-driven events may physiologically set human DC free from restraint by regulatory cells expressing surface CTLA-4. 相似文献
83.
Fasting is characterized by disrupted thyroid feedback, with suppressed levels of thyroid hormones and paraventricular thyrotropin releasing hormone (TRH). We found that third ventricle administration of the deiodinase inhibitor, iopanoic acid, dose-dependently reduced deiodinase type II (DII) activity selectively in the hypothalamus. This suppression of DII by iopanoic acid during fasting prevented elevated DII activity and blunted the decline in hypothalamic TRH mRNA levels. Because fasting-induced elevation in hypothalamic DII activity is paralleled by increased hypothalamic T3 concentration, our study suggests that T3 formation by DII in the hypothalamus is the cause of disrupted thyroid feedback during fasting. 相似文献
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Silvia Ligios Pere Anadón Francesca Castorina Carmine D’Amico Daniela Esu Elsa Gliozzi Pierparide Gramigna Marco Mola Giovanni Monegato 《Geobios》2012,45(4):351-367
Late Miocene brackish ostracods and molluscs collected in three Italian basins show noticeable differences in their taxonomic composition, despite their capability of dispersing across wide geographic areas. In the Venetian-Friulian Basin (northern Italy), the upper Tortonian sediments contain oligotypic ostracod assemblages including Hemicyprideis dacica dacica, Hemicytheria pejinovicensis, and Loxoconcha cf. L. josephi and few gastropods referable to Planorbidae and Stenothyroides, which are typical of the central Paratethys. In central Italy, the brackish ostracods and molluscs recovered from upper Tortonian-lower Messinian deposits from four Tuscan basins (Volterra-Radicondoli, Velona, Baccinello-Cinigiano, and Valdelsa) display high affinity at a generic level but strong endemicity at a specific level. At Cessaniti (southern Italy), the upper Tortonian unit contains oligotypic brackish ostracods and molluscs: Mediocytherideis (Sylvestra) posterobursa, Cyprideis ruggierii, Loxoconcha cf. L. biformata, and Zonocypris membranae quadricella characterise the ostracod fauna, while Granulolabium bicinctum and Hydrobia frauenfeldi are the dominant molluscs. The recovered ostracods have a strong affinity with brackish species from central and eastern Palaeo-Mediterranean areas, whereas the molluscs present a Paratethyan origin. Despite the fact that the basins are all brackish and partly coeval, the systematics of these assemblages highlights the absence of common species among the three studied areas. Geochemical analyses (stable isotopes and trace elements) are performed on ostracods, and 87Sr/86Sr ratios are established in molluscs and echinoids. The results suggest brackish environments with different compositions and origins of solutes in the three different areas. The Tuscan basins are characterised by brackish waters, with NaCl-enriched waters coming from aquifers of Triassic evaporite bedrock. The brackish deposits of the Venetian-Friulian Basin and Cessaniti are true marginal marine environments, although the northern basin may have been influenced by both the Paratethyan Sava Basin and the northern portion of the Palaeo-Mediterranean water bodies. 相似文献
86.
Effect of dietary docosahexaenoic acid on biosynthesis of docosahexaenoic acid from alpha-linolenic acid in young rats 总被引:2,自引:0,他引:2
Docosahexaenoic acid (DHA), a crucial nervous system n-3 PUFA, may be obtained in the diet or synthesized in vivo from dietary alpha-linolenic acid (LNA). We addressed whether DHA synthesis is regulated by the availability of dietary DHA in artificially reared rat pups, during p8 to p28 development. Over 20 days, one group of rat pups was continuously fed deuterium-labeled LNA (d5-LNA) and no other n-3 PUFA (d5-LNA diet), and a second group of rat pups was fed a d5-LNA diet with unlabeled DHA (d5-LNA + DHA diet). The rat pups were then euthanized, and the total amount of deuterium-labeled docosahexaenoic acid (d5-DHA) (synthesized DHA) as well as other n-3 fatty acids present in various body tissues, was quantified. In the d5-LNA + DHA group, the presence of dietary DHA led to a marked decrease (3- to 5-fold) in the total amount of d5-DHA that accumulated in all tissues that we examined, except in adipose. Overall, DHA accretion from d5-DHA was generally diminished by availability of dietary preformed DHA, inasmuch as this was found to be the predominant source of tissue DHA. When preformed DHA was unavailable, d5-DHA and unlabeled DHA were preferentially accreted in some tissues along with a net loss of unlabeled DHA from other organs. 相似文献
87.
Ronci M Bonanno E Colantoni A Pieroni L Di Ilio C Spagnoli LG Federici G Urbani A 《Proteomics》2008,8(18):3702-3714
Archival formalin-fixed paraffin-embedded (FFPE) tissues are a powerful tool for examining the clinical course of diseases. These specimens represent an incredible mine of valuable clinical and biological information for proteomic investigation. MALDI-TOF imaging MS (MALDI-IMS) is a protein profiling technique which enables the direct sampling of histological section; however, the quality of molecular data are strongly influenced by the tissue preparation condition. In fact, in previous years most of the studies employing such a technological platform have been conducted using cryo-preserved tissues. We have developed an in vitro approach using "tissue surrogate" samples in order to explore different protein unlocking procedures which might enable a suitable recovery of polypeptides for MS analysis. The developed protocols have been compared both by MALDI-TOF MS and nLC-MS(E) analysis either on surrogate samples or on FFPE specimen from human breast cancer. The collected evidence has been applied for the preparation of FFPE tissue sections following MALDI-IMS analysis. Our results outline the possibility to obtain valuable peptide mass spectra profiles form FFPE preparations by applying a combined two steps procedure of heat induced antigen retrieval (HIAR) in presence of EDTA and on target trypsin hydrolysis. A multivariate statistical evaluation is presented and discussed according to molecular spatial distributions and tissue morphology. 相似文献
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Chiara Donfrancesco Simonetta Palleschi Luigi Palmieri Barbara Rossi Cinzia Lo Noce Fabio Pannozzo Belinda Spoto Giovanni Tripepi Carmine Zoccali Simona Giampaoli 《PloS one》2013,8(10)