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991.
Asha Nair Manuela Simonetti Elsa Fabbretti Andrea Nistri 《Cellular and molecular neurobiology》2010,30(4):505-509
Cdk5 is an endogenous kinase activated by the neuronal-specific protein p35 and implicated in multiple neuronal functions,
including modulation of certain pain responses. We investigated whether Cdk5 could regulate ATP-gated P2X3 receptors that are members of the family of membrane proteins expressed by sensory neurons to transduce nociception in baseline
and chronic pain. To study the potential P2X3 receptor modulation by Cdk5, we co-transfected rat P2X3 receptors and Cdk5 into HEK cells and observed increased P2X3 receptor serine phosphorylation together with downregulation of receptor currents only when these genes were transfected
together with the gene of the Cdk5 activator p35. The changes in receptor responses were limited to depressed current amplitude
as desensitization and recovery were not altered. Transfection of p35 with P2X3 similarly downregulated receptor responses, suggesting that this phenomenon could be observed even with constitutive Cdk5.
The present data indicate a novel target to express the action of Cdk5 on membrane proteins involved in pain perception. 相似文献
992.
993.
Emanuela Viggiano Marcellino Monda Alessandro Viggiano Andrea Viggiano Caterina Aurilio Bruno De Luca 《Molecular and cellular biochemistry》2010,339(1-2):149-154
Previous studies have demonstrated that there is an increase in oxidative stress in the cerebral cortex of rats after repeated painful stimulation and that long-lasting pain increases the production of superoxide ion (O2 ?), nitric oxide and peroxynitrite due to the activation of AMPA and NMDA receptors. The purpose of the present study was to evaluate the possible role of O2 ? in the transmission of oro-facial pain. Formaldehyde 1% was injected subcutaneously into one vibrissal pad of adult male Sprague-Dawley rats as a model of persistent pain, then O2 ? production and superoxide dismutase (SOD) activity were evaluated in the left and right spinal trigeminal nuclei. O2 ? production was revealed using dihidroetidium (DHE) injected at 10 or 45 min after the formalin injection in conscious or anaesthetized rats. A histochemical assay for SOD was performed to evaluate the activity of SOD at 10 min after the formalin injection. The results showed a significant increase in O2 ? production in the homolateral nucleus at 45 min. However, there was no significant difference between the two sides at 10 min after the formalin injection. No significant difference was observed in SOD activity between the two sides of the spinal trigeminal nucleus. This study demonstrated that there is an increased production of O2 ? in the second phase but not in the first phase of the formalin test; thus O2 ? is involved in pain induced by inflammation, but not in acute pain. 相似文献
994.
Ákos Boros Ildikó Somogyi Péter Engelmann Andrea Lubics Dóra Reglodi Edit Pollák László Molnár 《Cell and tissue research》2010,339(3):649-653
Pituitary adenylate cyclase activating polypeptide (PACAP)-like molecules have been shown to be present in cocoon albumin
and in Eisenia fetida embryos at an early developmental stage (E1) by immunocytochemistry and radioimmunoassay. Here, we focus on detecting the
stage at which PAC1 receptor (PAC1R)-like immunoreactivity first appears in germinal layers and structures, e.g., various
parts of the central nervous system (CNS), in developing earthworm embryos. PAC1R-like immunoreactivity was revealed by Western
blot and Far Western blot as early as the E2 developmental stage, occurring in the ectoderm and later in specific neurons
of the developing CNS. Labeled CNS neurons were first seen in the supraesophageal ganglion (brain) and subsequently in the
subesophageal and ventral nerve cord ganglia. Ultrastructurally, PAC1Rs were located mainly on plasma membranes and intracellular
membranes, especially on cisternae of the endoplasmic reticulum. Therefore, PACAP-like compounds probably influence the differentiation
of germinal layers (at least the ectoderm) and of some neurons and might act as signaling molecules during earthworm embryonic
development. 相似文献
995.
Belli Mauro Ottolenghi Andrea Weiss Wolfgang 《Radiation and environmental biophysics》2010,49(3):463-468
Health effects of exposures at low doses and/or low dose rates are recognized as requiring intensive research activity to
answer several questions. To address these issues at a strategic level in Europe, with the perspective of integrating national
and EC efforts (in particular those within the Euratom research programmes), a “European High Level and Expert Group (HLEG)
on low dose risk research” was formed and carried out its work during 2008. The Group produced a report published by the European
Commission in 2009 and available on the website . The more important research issues identified by the HLEG were as follows: (a) the shape of dose–response for cancer; (b)
the tissue sensitivities for cancer induction; (c) the individual variability in cancer risk; (d) the effects of radiation
quality (type); (e) the risks from internal radiation exposure; and (f) the risks of, and dose response relationships for,
non-cancer diseases. In this paper, the radiation quality issues are especially considered, since they are closely linked
to health problems and related radioprotection in space and in emerging radiotherapeutic techniques (i.e., hadrontherapy).
The peculiar features of low-fluence, high-LET radiation exposures can question in particular the validity of the radiation-weighting
factor (w
R
) approach. Specific strategies are therefore needed to assess such risks. A multi-scale/systems biology approach, based on
mechanistic studies coordinated with molecular-epidemiological studies, is considered essential to elucidate differences and
similarities between specific effects of low- and high-LET radiation. 相似文献
996.
Vasantha Madhuri Kallakunta Andrea StaruchBulent Mutus 《Biochimica et Biophysica Acta (BBA)/General Subjects》2010
Background
Protein S-nitrosation is an important post-translational modification altering protein function. Interaction of nitric oxide with thiols is an active area of research, and is one of the mechanisms by which NO exerts its biological effects. Biotin switch assay is the method, which has been developed to identify S-nitrosated proteins. The major concern with biotin switch assay includes reducing disulfide which may lead to false positives. We report a modification of the biotin switch assay where sinapinic acid is utilized instead of ascorbate to eliminate potential artifacts in the detection of S-nitrosated proteins.Methods
The denitrosation ability of sinapinic acid was assessed by monitoring either the NO or NO2- released by chemiluminescent NO detection or by the griess assay, respectively. DTNB assay was used to compare disulfide reduction by ascorbate and sinapinic acid. Sinapinic acid and ascorbate were compared in the biotin switch detection of S-nitrosoproteins in RAW 264.7 cells ± S-nitrosocysteine (CysNO) exposure.Results
We show that sinapinic acid has the ability to denitrosate S-nitrosothiols at pH 7.0 and denitrate plus denitrosate at pHs 8 and 8.5. Unlike ascorbate, sinapinic acid degrades S-nitrosothiols, but it does not reduce disulfide bridges.Conclusions
Sinapinic acid denitrosate RSNO and does not reduce disulfides. Thus can readily replace ascorbate in detection of S-nitrosated proteins in biotin switch assay.General significance
The work described is important in view of protein S-nitrosation. In this study we provide an important modification that eliminates artifacts in widely used technique for detecting the S-nitrosoproteome, the biotin switch assay. 相似文献997.
998.
Andrea Hoffmeier Heike Betat Alexander Bluschke Robert Günther Sandy Junghanns Hans-J?rg Hofmann Mario M?rl 《Nucleic acids research》2010,38(13):4436-4447
CCA-adding enzymes are polymerases existing in two distinct enzyme classes that both synthesize the C-C-A triplet at tRNA 3′-ends. Class II enzymes (found in bacteria and eukaryotes) carry a flexible loop in their catalytic core required for switching the specificity of the nucleotide binding pocket from CTP- to ATP-recognition. Despite this important function, the loop sequence varies strongly between individual class II CCA-adding enzymes. To investigate whether this loop operates as a discrete functional entity or whether it depends on the sequence context of the enzyme, we introduced reciprocal loop replacements in several enzymes. Surprisingly, many of these replacements are incompatible with enzymatic activity and inhibit ATP-incorporation. A phylogenetic analysis revealed the existence of conserved loop families. Loop replacements within families did not interfere with enzymatic activity, indicating that the loop function depends on a sequence context specific for individual enzyme families. Accordingly, modeling experiments suggest specific interactions of loop positions with important elements of the protein, forming a lever-like structure. Hence, although being part of the enzyme’s catalytic core, the loop region follows an extraordinary evolutionary path, independent of other highly conserved catalytic core elements, but depending on specific sequence features in the context of the individual enzymes. 相似文献
999.
Taurine participates in a number of different physiologic and biologic processes in the kidney, often reflected by urinary excretion patterns. The kidney is key to aspects of taurine body pool size and homeostasis. This review will examine the renal-taurine interactions relative to ion reabsorption; renal blood flow and renal vascular endothelial function; antioxidant properties, especially in the glomerulus; and the role of taurine in ischemia and reperfusion injury. In addition, taurine plays a role in the renal cell cycle and apoptosis, and functions as an osmolyte during the stress response. The role of the kidney in adaptation to variations in dietary taurine intake and the regulation of taurine body pool size are described. Finally, the protective function of taurine against several kidney diseases is reviewed. 相似文献
1000.
Cappelli A Valenti S Mancini A Giuliani G Anzini M Altieri S Bortolussi S Ferrari C Clerici AM Zonta C Carraro F Filippi I Giorgi G Donati A Ristori S Vomero S Concas A Biggio G 《Bioconjugate chemistry》2010,21(12):2213-2221
Potential boron neutron capture therapy (BNCT) agents have been designed on the basis of the evidence about translocator protein (TSPO) overexpression on the outer mitochondrial membrane of tumor cells. The structure of the first TSPO ligand bearing a carborane cage (compound 2d) has been modified in order to find a suitable candidate for in vivo studies. The designed compounds were synthesized and evaluated for their potential interaction with TSPO and tumor cells. In vitro biological evaluation showed in the case of fluoromethyl derivative 4b a nanomolar TSPO affinity very similar to that of 2d, a significantly lower cytotoxicity, and a slightly superior performance as boron carrier toward breast cancer cells. Moreover, compound 4b could be used as a 1?F magnetic resonance imaging (MRI) agent as well as labeled with 11C or 1?F to obtain positron emission tomography (PET) radiotracers in order to apply the "see and treat" strategy in BNCT. 相似文献