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111.
Early European naturalists saw Amazonian landscapes as pristine, but modern research has found a complex historical ecology, similar to that of other tropical and temperate regions. Although the pristine myth has been thoroughly debunked, too many biodiversity researchers fail to incorporate historical ecology into their analyses. For a world society out of balance with its natural resource base, careful interpretation is essential to understand trends, including impoverishment of planetary biodiversity. If world society avoids civilizational collapse, parts of Amazonia's historical ecology can contribute to future sustainability and improved survival of its biodiversity. 相似文献
112.
Lisa GM van Baarsen Carla A Wijbrandts François Rustenburg Tineke Cantaert Tineke CTM van der Pouw Kraan Dominique L Baeten Ben AC Dijkmans Paul P Tak Cornelis L Verweij 《Arthritis research & therapy》2010,12(1):R11
Introduction
Cross-regulation between TNF and type I IFN has been postulated to play an important role in autoimmune diseases. Therefore, we determined the effect of TNF blockade in rheumatoid arthritis (RA) on the type I IFN response gene activity in relation to clinical response. 相似文献113.
van Halm VP Nurmohamed MT Twisk JW Dijkmans BA Voskuyl AE 《Arthritis research & therapy》2006,8(5):R151-6
Rheumatoid arthritis (RA) is characterized by inflammation and an increased risk for cardiovascular disease (CVD). This study
investigates possible associations between CVD and the use of conventional disease-modifying antirheumatic drugs (DMARDs)
in RA. Using a case control design, 613 RA patients (5,649 patient-years) were studied, 72 with CVD and 541 without CVD. Data
on RA, CVD and drug treatment were evaluated from time of RA diagnosis up to the first cardiovascular event or the end of
the follow-up period. The dataset was categorized according to DMARD use: sulfasalazine (SSZ), hydroxychloroquine (HCQ) or
methotrexate (MTX). Odds ratios (ORs) for CVD, corrected for age, gender, smoking and RA duration, were calculated per DMARD
group. Patients who never used SSZ, HCQ or MTX were used as a reference group. MTX treatment was associated with a significant
CVD risk reduction, with ORs (95% CI): 'MTX only', 0.16 (0.04 to 0.66); 'MTX and SSZ ever', 0.20 (0.08 to 0.51); and 'MTX,
SSZ and HCQ ever', 0.20 (0.08 to 0.54). The risk reductions remained significant after additional correction for the presence
of rheumatoid factor and erosions. After correction for hypertension, diabetes and hypercholesterolemia, 'MTX or SSZ ever'
and 'MTX, SSZ and HCQ ever' showed significant CVD risk reduction. Rheumatoid factor positivity and erosions both increased
CVD risk, with ORs of 2.04 (1.02 to 4.07) and 2.36 (0.92 to 6.08), respectively. MTX and, to a lesser extent, SSZ were associated
with significantly lower CVD risk compared to RA patients who never used SSZ, HCQ or MTX. We hypothesize that DMARD use, in
particular MTX use, results in powerful suppression of inflammation, thereby reducing the development of atherosclerosis and
subsequently clinically overt CVD. 相似文献
114.
Leopoldino AM Canduri F Cabral H Junqueira M de Marqui AB Apponi LH da Fonseca IO Domont GB Santos DS Valentini S Bonilla-Rodriguez GO Fossey MA de Azevedo WF Tajara EH 《Protein expression and purification》2006,47(2):614-620
The human cyclin-dependent kinase 9 (CDK9) protein was expressed in E. coli BL21 using the pET23a vector at 30 degrees C. Several milligrams of protein were purified from soluble fraction using ionic exchange and ATP-affinity chromatography. The structural quality of recombinant CDK9 and the estimation of its secondary structure were obtained by circular dichroism. Structural models of CDK9 presented 26% of helices in agreement with the spectra by circular dichroism analysis. This is the first report on human CDK9 expression in Escherichia coli and structure analysis and provides the first step for the development of CDK9 inhibitors. 相似文献
115.
Sandra S. Chan Hugo P. Monteiro Fernanda Schindler Arnold Stern Virginia B.C. Junqueira 《Free radical research》2013,47(6):843-856
α-Tocopherol augmentation in human neutrophils was investigated for effects on neutrophil activation and tyrosine phosphorylation of proteins, through its modulation of protein kinase C (PKC) and tyrosine phosphatase activities. Incubation of neutrophils with α-tocopherol succinate (TS) resulted in a dose-dependent incorporation into cell membranes, up to 2.5 nmol/2 × 106 cells. A saturating dose of TS (40 μmol/l) inhibited oxidant production by neutrophils stimulated with phorbol myristate acetate (PMA) or opsonized zymosan (OZ) by 86 and 57%, as measured by luminol-amplified chemiluminescence (CL). With PMA, TS inhibited CL generation to a similar extent to staurosporine (10 nmol/l) or genistein (100 μmol/l), and much more than Trolox (40 μmol/l). With OZ, TS inhibited CL to a similar extent to Trolox. Neutrophil PKC activity was inhibited 50% or more by TS or staurosporine. The enzyme activity was unaffected by genistein or Trolox, indicating a specific interaction of α-tocopherol. TS or Trolox increased protein tyrosine phosphorylation in resting neutrophils, and as with staurosporine further increased tyrosine phosphorylation in PMA-stimulated neutrophils, while the tyrosine kinase (TK) inhibitor genistein diminished phosphorylation. These effects in resting or PMA-stimulated neutrophils were unrelated to protein tyrosine phosphatase (PTP) activities, which were maintained or increased by TS or Trolox. In OZ-stimulated neutrophils, on the other hand, all four compounds inhibited the increase in tyrosine-phosphorylated proteins. In this case, the effects of pre-incubation with TS or Trolox corresponded with partial inhibition of the marked (85%) decrease in PTP activity induced by OZ. These results indicate that α-tocopherol inhibits PMA-activation of human neutrophils by inhibition of PKC activity, and inhibits tyrosine phosphorylation and activation of OZ-stimulated neutrophils also through inhibition of phosphatase inactivation. 相似文献
116.
The internal transcribed spacer 2 (ITS2) is a small non-coding region located inside the nuclear ribosomal DNA cluster. ITS2
sequence variability is thought to be appropriate to differentiate species and for phylogenetic reconstructions analyses,
which can be further improved if structural information is considered. We evaluated the potential of ITS2 as a molecular marker
for phylogenetic inference in Calliphoridae (Diptera: Brachycera) using a broad range of inference methods and different substitution
models, accounting or not for structural information. Sequence analyses revealed a hierarchically organized pattern of sequence
variation and a small level of nucleotide substitution saturation. Intragenomic variation due to small sequence repeats was
found mainly in the most variable domain (IV), but it has no significant impact on the phylogenetic signal at the species
level. Inferred secondary structures revealed that GC pairs are more frequently found flanking bulges and loops regions in
more conserved domains, thus ensuring structure stability. In the phylogenetic analyses, the use of substitution models accounting
for structural information significantly improves phylogenetic inference in both neighbour-joining and Bayesian analyses,
although the former provides limited resolution for dealing with highly divergent sequences. For Bayesian analyses, a significant
improvement in likelihood was observed when considering structure information, although with small changes in topology and
overall support, probably reflecting better evolutionary rates estimates. Based on these findings, ITS2 is a suitable molecular
marker for phylogenetic analyses in Calliphoridae, at both species and generic level. 相似文献
117.
Junqueira AL Tavares VR Martins RM Frauzino KV Silva AM Rodrigues IM Minamisava R Teles SA 《Memórias do Instituto Oswaldo Cruz》2011,106(1):113-116
Recently, it was suggested that maternal hepatitis B surface antigen antibodies (anti-HBs) acquired transplacentally could play a negative role in newborn infants' immune response to the hepatitis B vaccine. We compared the hepatitis B virus (HBV) vaccine response in infants born to mothers previously vaccinated against HBV (n = 91) to infants born to mothers who were not previously vaccinated (n = 221). All newborn infants received three intramuscular doses (10 μg) of HBV vaccine (Butang?) at 0,1 and six months. The first dose was administered at the maternity hospital within 12 h of birth. The geometric mean titres of anti-HBs were not different among newborn infants born to mothers who were anti-HBs-negative (492.7 mIU/mL) and anti-HBs-positive (578.7 mIU/mL) (p = 0.38). Eight infants did not respond to the HBV vaccine. Of them, six were born to anti-HBs-negative mothers and two were born to mothers with anti-HBs titres less than 50 mlU/mL. Despite the mother's anti-HBs-positive status, our data show a good immunogenicity of the Brazilian HBV recombinant vaccine in neonates. 相似文献
118.
James Angus Fraser André B. Junqueira Nicholas C. Kawa Claide P. Moraes Charles R. Clement 《Human ecology: an interdisciplinary journal》2011,39(4):395-406
A recent archaeological survey demonstrates that one of the most durable of all forms of pre-Columbian landscape transformation,
Amazonian Dark Earths (ADE; soils formed by pre-Columbian settlement), are widespread along the course of the Madeira River,
Central Amazonia, Brazil. We hypothesize that processes of crop cultivation and management by human populations today in landscapes
that were intensively transformed during the pre-Columbian period will diverge from those in environments where human agency
has not left such a heavy footprint. In order to test this hypothesis, we compare bitter manioc fields, homegardens and secondary
forests on ADE with those on non-anthropogenic soils along the lower and middle Madeira River. We demonstrate that crop species
and landrace populations diverge on anthropogenic and non-anthropogenic soils as a result of the interaction between human
selection and management, soil physical and chemical properties, and plant responses over time. Hence, crop species selection
and abundance and therefore agrobiodiversity is contingent on anthropogenic soils in Central Amazonia. 相似文献
119.
Cristiane Aparecida Pereira Anna Carolina Borges Pereira da Costa Ana Karina Silva Machado Miltom Beltrame Júnior Maria Stella Amorin Costa Zöllner Juliana Campos Junqueira Antonio Olavo Cardoso Jorge 《Mycopathologia》2011,171(2):103-109
Candida strains can cause oral candidosis, as well as nipples candidosis and lead to premature weaning or yeast transmission. The
aim of this study was to evaluate 51 Candida isolates obtained from the oral cavities of infants during breastfeeding and mothers’ oral cavities and nipples, their enzymatic
activity and their sensitivity to amphotericin B, fluconazole and Baccharis dracunculifolia essential oil. Among the studied strains, 96.1% produced phospholipase and 78.4% produced proteinase. The antifungal resistance
was only observed among isolates of C. albicans, for which three strains showed a resistant activity to fluconazole and one showed a resistant activity to amphotericin B.
All strains were sensitive to B. dracunculifolia essential oil with MIC between 0.2 and 6.25 mg/ml. It was concluded that most of the strains showed significant enzymatic
activity and were sensitive to amphotericin B and fluconazole. B. dracunculifolia essential oil inhibited the growth of all strains, including the ones resistant to commercial antifungal agents. 相似文献
120.
Dinler A. Antunes Maurício M. Rigo Marialva Sinigaglia Rúbia M. de Medeiros Dennis M. Junqueira Sabrina E. M. Almeida Gustavo F. Vieira 《PloS one》2014,9(1)
The Human Immunodeficiency Virus type 1 protease enzyme (HIV-1 PR) is one of the most important targets of antiretroviral therapy used in the treatment of AIDS patients. The success of protease-inhibitors (PIs), however, is often limited by the emergence of protease mutations that can confer resistance to a specific drug, or even to multiple PIs. In the present study, we used bioinformatics tools to evaluate the impact of the unusual mutations D30V and V32E over the dynamics of the PR-Nelfinavir complex, considering that codons involved in these mutations were previously related to major drug resistance to Nelfinavir. Both studied mutations presented structural features that indicate resistance to Nelfinavir, each one with a different impact over the interaction with the drug. The D30V mutation triggered a subtle change in the PR structure, which was also observed for the well-known Nelfinavir resistance mutation D30N, while the V32E exchange presented a much more dramatic impact over the PR flap dynamics. Moreover, our in silico approach was also able to describe different binding modes of the drug when bound to different proteases, identifying specific features of HIV-1 subtype B and subtype C proteases. 相似文献