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31.
Zoppellaro G Sakurai N Kataoka K Sakurai T 《Bioscience, biotechnology, and biochemistry》2004,68(9):1998-2000
The redox state of type I Cu in Myrothecium verrucaria bilirubin oxidase (BO), a multicopper oxidase utilized in the clinical investigation of liver, is an equilibrium state of the oxidized and reduced forms, reflected in the reversible absorption and electron paramagnetic resonance (EPR) spectral changes depending on pH. 相似文献
32.
Codolo G Mazzi P Amedei A Del Prete G Berton G D'Elios MM de Bernard M 《Cellular microbiology》2008,10(11):2355-2363
The Helicobacter pylori neutrophil-activating protein (HP-NAP) is able in vitro to elicit IL-12 and IL-23 production via agonistic interaction with toll-like receptor 2, and to promote Th1 polarization of allergen-specific T-cell responses. This study was aimed to assess whether systemic/intraperitoneal and/or mucosal HP-NAP administration inhibited the Th2-mediated bronchial inflammation using a mouse model of allergic asthma induced by inhaled ovalbumin (OVA). Systemic HP-NAP delivery markedly reduced the lung eosinophilia in response to repeated challenge with aerosolized OVA. Likewise, the production of IL-4, IL-5 and GM-CSF was significantly lower in the bronchoalveolar lavage of animals treated with systemic HP-NAP plus OVA than that of animals treated with OVA alone. Systemic HP-NAP also significantly resulted in both reduction of total serum IgE and increase of IL-12 plasma levels. Mucosal administration of HP-NAP was equally successful as the systemic delivery in reducing eosinophilia, IgE and Th2 cytokine levels in bronchoalveolar lavage. However, no suppression of lung eosinophilia and bronchial Th2 cytokines was observed in toll-like receptor 2-knock-out mice following HP-NAP treatment. These results identify HP-NAP as a candidate for novel strategies of prevention and treatment of allergic diseases. 相似文献
33.
CD8+ CD28- T regulatory lymphocytes inhibiting T cell proliferative and cytotoxic functions infiltrate human cancers 总被引:1,自引:0,他引:1
Filaci G Fenoglio D Fravega M Ansaldo G Borgonovo G Traverso P Villaggio B Ferrera A Kunkl A Rizzi M Ferrera F Balestra P Ghio M Contini P Setti M Olive D Azzarone B Carmignani G Ravetti JL Torre G Indiveri F 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(7):4323-4334
Tumor growth is allowed by its ability to escape immune system surveillance. An important role in determining tumor evasion from immune control might be played by tumor-infiltrating regulatory lymphocytes. This study was aimed at characterizing phenotype and function of CD8+ CD28- T regulatory cells infiltrating human cancer. Lymphocytes infiltrating primitive tumor lesion and/or satellite lymph node from a series of 42 human cancers were phenotypically studied and functionally analyzed by suppressor assays. The unprecedented observation was made that CD8+ CD28- T regulatory lymphocytes are almost constantly present and functional in human tumors, being able to inhibit both T cell proliferation and cytotoxicity. CD4+ CD25+ T regulatory lymphocytes associate with CD8+ CD28- T regulatory cells so that the immunosuppressive activity of tumor-infiltrating regulatory T cell subsets, altogether considered, may become predominant. The infiltration of regulatory T cells seems tumor related, being present in metastatic but not in metastasis-free satellite lymph nodes; it likely depends on both in situ generation (via cytokine production) and recruitment from the periphery (via chemokine secretion). Collectively, these results have pathogenic relevance and implication for immunotherapy of cancer. 相似文献
34.
Annalisa Pezzolo Giorgio Gimelli Amnon Cohen Antonella Lavaggetto Cesare Romano Giuseppina Fogu Orsetta Zuffardi 《Human genetics》1993,92(1):23-27
In situ hybridization of a telomeric (TTA-GGG)
n
sequence to metaphases from three cases of ring chromosome, involving respectively chromosomes 4, 16, and 20, showed the presence of the cognate sequences in all three rings. To investigate whether these ring chromosomes originated by telomere-telomere fusion, we determined, by in situ hybridization, whether telomere-associated sequences and/or specific distal sequences were still present in the ring chromosomes. The finding that these sequences were preserved in all the ring chromosomes strongly indicates that they originated by telomere-telomere fusion. All three subjects carrying the ring chromosomes are affected by the so-called ring syndrome, with failure to thrive, minor dysmorphic signs and no major anomalies. The r(4) patient has the ring in mosaic form with a normal cell line and has normal intelligence. The r(16) and the r(20) patients have moderate mental retardation and suffer from seizures. We conclude that the ring syndrome, even in its more severe manifestation, is caused by ring chromosome instability. 相似文献
35.
Giorgio Forti 《Plant biosystems》2013,147(1-2):220-223
Abstract EFFECT OF TREATMENT WITH IAA OF PEA INTERNODE SECTIONS ON THE OXIDATIVE PHOSPHORYLATION OF THEIR MITOCHONDRIA. — It was previously shown that auxin treatment raises the level of ATP in pea stem sections, under the conditions where the hormone stimulates growth (MARRé AND FORTI). It is also known that under the same conditions auxin stimulates oxygen uptake (MARRé, FORTI e ARRIGONI; MARRÉ and FORTI), and that the auxin induced respiration is most probably mediated by cytochrome oxidase (MARRÉ, FORTI and GAUR). However, auxin has no effect when added to isolated mitochondria. In this paper, the effect of auxin treatment of the tissue on the activity of mitochondria isolated after the hormone treatment has been studied. It has been found that oxidative phosphorylation of mitochondria from the auxin treated pea stem sections is 13% higher than that of controi sections. The auxin effect is significant at 96% probabilities. There is no effect of the hormone on the P/O ratio. 相似文献
36.
Sessa Giovanna Steindler Corinna Morelli Giorgio Ruberti Ida 《Plant molecular biology》1998,38(4):609-622
We report the isolation and characterization of two Arabidopsis homeobox genes highly related to the Athb-8 gene. The full-length cDNAs encode proteins of 841 and 852 amino acids which we have designated Athb-9 and -14, respectively. Athb-8, -9 and -14 are members of a small family of HD-Zip proteins (HD-ZIP III) characterized by a HD-Zip motif confined to the N-terminus of the polypeptide. The spatial organization of the HD-Zip domain of Athb-8, -9 and -14 is different from that of the Athb-1 (a member of the HD-ZIP I family) and Athb-2 (a member of the HD-ZIP II family) HD-Zip domains. DNA binding analysis performed with random-sequence DNA templates showed that the Athb-9 HD-Zip (HD-Zip-9) domain, but not the Athb-9 HD alone, binds to DNA. The HD-Zip-9 domain recognizes a 11 bp pseudopalindromic sequence (GTAAT(G/C)ATTAC), as determined by selecting high-affinity binding sites from random-sequence DNA. Moreover, gel retardation assays demonstrated that the HD-Zip-9 domain binds to DNA as a dimer. These data support the notion that the HD-ZIP III domain interacts with DNA recognition elements in a fashion similar to the HD-ZIP I and II domains. 相似文献
37.
Paolo d’Errico Marina Boido Antonio Piras Valeria Valsecchi Elena De Amicis Denise Locatelli Silvia Capra Francesco Vagni Alessandro Vercelli Giorgio Battaglia 《PloS one》2013,8(12)
Loss of the survival motor neuron gene (SMN1) is responsible for spinal muscular atrophy (SMA), the most common inherited cause of infant mortality. Even though the SMA phenotype is traditionally considered as related to spinal motor neuron loss, it remains debated whether the specific targeting of motor neurons could represent the best therapeutic option for the disease. We here investigated, using stereological quantification methods, the spinal cord and cerebral motor cortex of ∆7 SMA mice during development, to verify extent and selectivity of motor neuron loss. We found progressive post-natal loss of spinal motor neurons, already at pre-symptomatic stages, and a higher vulnerability of motor neurons innervating proximal and axial muscles. Larger motor neurons decreased in the course of disease, either for selective loss or specific developmental impairment. We also found a selective reduction of layer V pyramidal neurons associated with layer V gliosis in the cerebral motor cortex. Our data indicate that in the ∆7 SMA model SMN loss is critical for the spinal cord, particularly for specific motor neuron pools. Neuronal loss, however, is not selective for lower motor neurons. These data further suggest that SMA pathogenesis is likely more complex than previously anticipated. The better knowledge of SMA models might be instrumental in shaping better therapeutic options for affected patients. 相似文献
38.
The binding of tritium-labelled 7,12-dimethylbenz[a]anthracene (DMBA), benzo[a]pyrene (BP) and 3-methylcholanthrene (MCA) to DNA or polynucleotides in vitro was re-examined both in the presence and in the absence of rat liver or human placental microsomes.A high level of non-enzymatic binding was evident when thymus DNA was used as acceptor. This non-enzymatic binding made it difficult to determine the effect of microsomes, except in the case of BP when induced rat microsomes were used. Better results were obtained using polynucleotides: a definite microsome-dependent binding occurred between all the polynucleotides and all the hydrocarbons tested.No clear evidence of binding catalysed by microsomes from human placenta was found except in polynucleotide-BP interactions: further studies are required to completely evaluate the ability of such nucleic acid-microsomal system for testing in vitro possible oncogenic substances in animals and humans. 相似文献
39.
Gil-Agusti MT Campostrini N Zolla L Ciambella C Invernizzi C Righetti PG 《Proteomics》2005,5(3):710-718
Two species of the genus Coffea, Coffea arabica (Colombia) and Coffea canephora (Indiano Robusta) were analysed by two-dimensional (2-D) maps in order to obtain fingerprints of the expressed polypeptide chains and to determine which ones would characterize the two species. Green beans were milled under liquid nitrogen. A dry powder was produced by three different extraction protocols aimed at eliminating interfering substances (polyphenols). A reduced powder was produced by two successive extractions performed in acetone. Trichloroacetic acid (TCA; 10% w/v) and beta-mercaptoethanol (0.07% v/v) in acetone were used for the first extraction (a) and 10% w/v TCA in acetone was used for the second extraction (b). Proteins were then solubilized in a solution (40 microL per 1 mg powder) containing 7 M urea, 2 M thiourea, 3% w/v 3-(3-cholamidopropyldimethyl-amino)-1-propanesulfate, 1% v/v carrier ampholytes, 40 mM Tris, 5 mM tributylphosphine and 10 mM acrylamide as alkylating agent. Following incubation at room temperature for 1 hour and centrifugation (7000 rpm for 20 minutes), the supernatant was used for 2-D electrophoresis. The proteins were revealed by Sypro Ruby staining. Master maps of the five replicas of each species were compared by PDQuest analysis. The results of this differential proteome analysis were: sixteen proteins were expressed solely in C. canephora (var. Indiano Robusta) and five proteins were only found in C. arabica (var. Colombia). Another eight proteins were up-regulated in C. canephora (var. Indiano Robusta) in comparison to C. arabica (var. Colombia) and one was down-regulated in the same comparison. A number of these polypeptide chains were further characterized by mass spectrometry in the matrix-assisted laser desorption/ionisation-time of flight mode. Additionally, considering the low number of protein sequences of Coffea present in the databases we also investigated some spots with a more powerful tool, reversed phase-high-performance liquid chromatography-electrospray ionisation-tandem mass spectrometry, thus obtaining an internal peptide sequence. The general properties of the identified proteins are presented and discussed. 相似文献
40.
Enantioselective Preparation,Conformational Analysis and Absolute Configuration of Highly Substituted Aziridines 下载免费PDF全文
Giorgio Bencivenni Paolo Righi Lodovico Lunazzi Silvia Ranieri Michele Mancinelli Andrea Mazzanti 《Chirality》2015,27(12):875-887
The first example of organocatalytic aziridination reaction of α‐substituted‐α,β‐unsaturated ketones is presented. The reaction was found to be highly enantio‐ and diastereoselective, yielding N‐tosylated aziridines. Low‐temperature nuclear magnetic resonance (NMR) spectra allowed for the determination of the N‐inversion barrier, that was found to be quite lower with respect to unsubstituted aziridines. A thorough conformational analysis supported by low‐temperature NMR data allowed for the determination of the absolute configuration of the main stereoisomer by means of time‐dependent Density Functional Theory simulation of the electronic circular dichroism spectra. Chirality 27:875–887, 2015. © 2015 Wiley Periodicals, Inc. 相似文献