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41.
Fernanda Ferreira Cruz Lucas Felipe Bastos Horta Lígia de Albuquerque Maia Miquéias Lopes-Pacheco André Benedito da Silva Marcelo Marco Morales Cassiano Felippe Gon?alves-de-Albuquerque Christina Maeda Takiya Hugo Caire de Castro-Faria-Neto Patricia Rieken Macedo Rocco 《PloS one》2016,11(1)
Silicosis is an occupational lung disease with no effective treatment. We hypothesized that dasatinib, a tyrosine kinase inhibitor, might exhibit therapeutic efficacy in silica-induced pulmonary fibrosis. Silicosis was induced in C57BL/6 mice by a single intratracheal administration of silica particles, whereas the control group received saline. After 14 days, when the disease was already established, animals were randomly assigned to receive DMSO or dasatinib (1 mg/kg) by oral gavage, twice daily, for 14 days. On day 28, lung morphofunction, inflammation, and remodeling were investigated. RAW 264.7 cells (a macrophage cell line) were incubated with silica particles, followed by treatment or not with dasatinib, and evaluated for macrophage polarization. On day 28, dasatinib improved lung mechanics, increased M2 macrophage counts in lung parenchyma and granuloma, and was associated with reduction of fraction area of granuloma, fraction area of collapsed alveoli, protein levels of tumor necrosis factor-α, interleukin-1β, transforming growth factor-β, and reduced neutrophils, M1 macrophages, and collagen fiber content in lung tissue and granuloma in silicotic animals. Additionally, dasatinib reduced expression of iNOS and increased expression of arginase and metalloproteinase-9 in silicotic macrophages. Dasatinib was effective at inducing macrophage polarization toward the M2 phenotype and reducing lung inflammation and fibrosis, thus improving lung mechanics in a murine model of acute silicosis. 相似文献
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43.
Eva Raquel Neves Stephan Schäfer Alan Phillips João Canejo Maria Filomena Macedo 《International biodeterioration & biodegradation》2009,63(3):267-272
With many important artistic works and documents made of paper, and thus susceptible to biodeterioration by fungi, research is required in an effort to replace toxic chemical products with other more benign ones. In this work the antifungal effect of methyl and propyl paraben mixtures at different concentrations was evaluated. The fungi used in the experiments were a Cladosporium species and Penicillium corylophilum, both of which are well known as paper-biodeteriorating fungi. The results demonstrate that a mixture of 0.5% methyl paraben and 1% propyl paraben, in 85% ethanolic solution, is the lowest concentration necessary to provide an efficient antifungal action. A deacidification agent, 5% calcium propionate, was added to this mixture to produce a multi-purpose formulation to treat acidification and fungal contamination of paper documents. Tests carried out on paper samples before and after application of this mixture showed only a minor increase in yellowing and a slight decrease in tensile strength, while substantially raising the pH, and thus the alkaline reserve, and also a slight increase in the percentage of deformation. 相似文献
44.
Luís Guedes-Martins Rita Gaio Joaquim Saraiva Sofia Cerdeira Liliana Matos Elisabete Silva Filipe Macedo Henrique Almeida 《PloS one》2015,10(3)
Background
Cyclic endometrial neoangiogenesis contributes to changes in local vascular patterns and is amenable to non-invasive assessment with Doppler sonography. We hypothesize that the uterine artery (UtA) impedance, measured by its pulsatility index (PI), exhibits a regular pattern during the normal menstrual cycle. Therefore, the main study objective was to derive normative new day-cycle-based reference ranges for the UtA-PI during the entire cycle from days 1 to 34 according to the isolated time effect and potential confounders such as age and parity.Methods
From January 2009 to December 2012, a cross-sectional study of 1,821 healthy women undergoing routine gynaecological ultrasound was performed. The Doppler flow of the right and left UtA-PI was studied transvaginally by colour and pulsed Doppler imaging. The mean right and left values and the presence or absence of a bilateral protodiastolic notch were recorded. Reference intervals for the PI according to the cycle day were generated by classical linear regression.Results
The majority of patients (97.5%) presented unilateral or bilateral UtA notches. The crude 5th, 50th, and 95th reference percentile curves of the UtA-PI at 1–34 days of the normal menstrual cycle were derived. In all curves, a progressive significant decrease occurred during the first 13 days, followed by an increase and recovery in the UtA-PI. The adjusted 5th, 50th, and 95th reference percentile curves for the effects of age and parity were also obtained. These two conditions generated an approximately identical UtA-PI pattern during the cycle, except with small but significant reductions at the temporal extremes.Conclusions
The median, 5th, and the 95th percentiles of the UtA-PI decrease during the first third of the menstrual cycle and recover to their initial values during the last two thirds of the cycle. The rates of decrease and recovery depend significantly on age and parity. 相似文献45.
Sheila Akinyi Okoth Joseph F. Abdallah Nicolas Ceron Malti R. Adhin Javin Chandrabose Karanchand Krishnalall Curtis S. Huber Ira F. Goldman Alexandre Macedo de Oliveira John W. Barnwell Venkatachalam Udhayakumar 《PloS one》2015,10(5)
Guyana and Suriname have made important progress in reducing the burden of malaria. While both countries use microscopy as the primary tool for clinical diagnosis, malaria rapid diagnostic tests (RDTs) are useful in remote areas of the interior where laboratory support may be limited or unavailable. Recent reports indicate that histidine-rich protein 2 (PfHRP2)-based diagnostic tests specific for detection of P. falciparum may provide false negative results in some parts of South America due to the emergence of P. falciparum parasites that lack the pfhrp2 gene, and thus produce no PfHRP2 antigen. Pfhrp2 and pfhrp3 genes were amplified in parasite isolates collected from Guyana and Suriname to determine if there were circulating isolates with deletions in these genes. Pfhrp3 deletions were monitored because some monoclonal antibodies utilized in PfHRP2-based RDTs cross-react with the PfHRP3 protein. We found that all 97 isolates from Guyana that met the inclusion criteria were both pfhrp2- and pfhrp3-positive. In Suriname (N = 78), 14% of the samples tested were pfhrp2-negative while 4% were pfhrp3-negative. Furthermore, analysis of the genomic region proximal to pfhrp2 and pfhrp3 revealed that genomic deletions extended to the flanking genes. We also investigated the population substructure of the isolates collected to determine if the parasites that had deletions of pfhrp2 and pfhrp3 belonged to any genetic subtypes. Cluster analysis revealed that there was no predominant P. falciparum population substructure among the isolates from either country, an indication of genetic admixture among the parasite populations. Furthermore, the pfhrp2-deleted parasites from Suriname did not appear to share a single, unique genetic background. 相似文献
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Yanqin Ren Szu Han Huang Amanda B. Macedo Adam R. Ward Winiffer D. Conce Alberto Thais Klevorn Louise Leyre Dennis C. Copertino Talia M. Mota Dora Chan Ronald Truong Thomas Rohwetter Paul Zumbo Friederike Dündar Doron Betel Colin Kovacs Erika Benko Alberto Bosque R. Brad Jones 《Journal of virology》2021,95(15)
48.
Filipe Anibal Carvalho‐Costa Silvia M Dos Santos Marize Quinhones Pires Catarina Macedo Lopes François Noireau Raquel S. Pacheco 《Journal of vector ecology》2010,35(2):295-300
Chagas disease remains a public health concern in Brazil and other Latin American countries, mainly due to the potential domiciliation of native triatomine species. We analyzed the genetic variability of Triatoma pseudomaculata in sylvatic and peridomestic ecotopes throughout three localities in the northeastern state of Bahia, Brazil. We studied polymorphisms generated by random amplified polymorphic DNA (RAPD) and isoenzyme electrophoresis analyses. Based on RAPD analysis, each specimen was assigned to one of three genetic clusters. Although all sylvatic specimens from one locality were grouped into the same cluster, sylvatic and peridomestic specimens from the other two localities were broadly distributed between the remaining two clusters, suggesting that geographic population structuring was not occurring. Furthermore, isoenzyme analysis suggested that distinct populations were in Hardy‐Weinberg equilibrium. Low statistical values for Wright's Fst index also supported the absence of population structuring and suggested the occurrence of panmixia. We conclude that genetic flow occurs between sylvatic and peridomestic T. pseudomaculata populations, probably as a consequence of passive and active dispersion of the insects, associated with deforestation and anthropic transformations. 相似文献
49.
Brian J. Goodfellow Iven C. N. Duarte Anjos L. Macedo Brian F. Volkman Sofia G. Nunes I. Moura John L. Markley José J. G. Moura 《Journal of biological inorganic chemistry》2010,15(3):409-420
The Ni(II) and Zn(II) derivatives of Desulfovibrio vulgaris rubredoxin (DvRd) have been studied by NMR spectroscopy to probe the structure at the metal centre. The βCH2 proton pairs from the cysteines that bind the Ni(II) atom have been identified using 1D nuclear Overhauser enhancement (NOE)
difference spectra and sequence specifically assigned via NOE correlations to neighbouring protons and by comparison with
the published X-ray crystal structure of a Ni(II) derivative of Clostridium pasteurianum rubredoxin. The solution structures of DvRd(Zn) and DvRd(Ni) have been determined and the paramagnetic form refined using
pseudocontact shifts. The determination of the magnetic susceptibility anisotropy tensor allowed the contact and pseudocontact
contributions to the observed chemical shifts to be obtained. Analysis of the pseudocontact and contact chemical shifts of
the cysteine Hβ protons and backbone protons close to the metal centre allowed conclusions to be drawn as to the geometry
and hydrogen-bonding pattern at the metal binding site. The importance of NH–S hydrogen bonds at the metal centre for the
delocalization of electron spin density is confirmed for rubredoxins and can be extrapolated to metal centres in Cu proteins:
amicyanin, plastocyanin, stellacyanin, azurin and pseudoazurin. 相似文献
50.