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101.
Spatio-temporal variability of the winter phytoplankton distribution across the Catalan and North Balearic fronts (NW Mediterranean) 总被引:1,自引:0,他引:1
The qualitative and quantitative composition of the phytoplankton
assemblages of the Catalano-Balearic Sea (NW Mediterranean) was examined in
relationship with frontal boundaries and short-term meteorological forcing
originated by an intense wind storm. Data were obtained during February
1990, before and after strong NW winds, from several transects across the
Catalan (continental side) and North Balearic (Balearic Islands side)
shelf/slope fronts. High chlorophyll concentrations and diatom dominance
inshore of the Catalan Front were typical of the winter-spring
phytoplankton maximum. However, offshore of the Catalan Front, diatoms were
scarce and the phytoplankton assemblage was dominated by coccolithophorids.
In spite of weak density stratification, a deep chlorophyll maximum (DCM)
was well developed, before the storm, offshore and appeared to cause a
pulse of new production, as suggested by increased oxygen concentrations in
the vicinity of the DCM. The results presented here indicate the existence
of a persistent association between the distribution of distinct
phytoplankton assemblages and hydrographic characteristics of the studied
area. Our results also show that, at least during an important part of the
winter-spring bloom period of the Catalano-Balearic Sea, high phytoplankton
biomass offshore of the Catalan Front is not associated with the diatom
dominance typically found in coastal waters and other offshore areas of the
NW Mediterranean. This finding has biogeochemical implications in
relationship with vertical export fluxes of particulate matter.
相似文献
102.
Mirta Cavieres Marcelo Surez Gabriel Vern Luis Abel Quiones Nelson Miguel Varela 《Biomédica : revista del Instituto Nacional de Salud》2021,41(3):5840
We present the clinical case of a 10-year-old patient diagnosed with dilated cardiomyopathy who registered INR values above 10 upon receiving standard doses of acenocoumarol, as well as other values reported as uncoagulable, forcing the discontinuation and restart of treatment more than once. Expected and stable INR levels were achieved after more than 30 days of treatment, surprisingly with half the recommended dose for a patient of her age and weight. We decided to conduct a retrospective pharmacogenomic analysis including nucleotide genetic polymorphisms (SNPs) with different degrees of association with the dose/response to antivitamin K (AVK) drugs: rs2108622 (gene CYP4F2), rs9923231, rs7294 (gene VKORC1), rs1799853, and rs1057910 (CYP2C9 gene) using TaqMan® RT-PCR. The patient was homozygous for rs9923231 (VKORC1) and heterozygous for rs2108622 (CYP4F2), a genetic profile strongly associated with a requirement of lower AVK doses as shown by national and international evidence.In conclusion, the pharmacogenetic analysis confirmed that this patient''s genetic conditions, involving low expression of the VKA therapeutic target, required a lower dose than that established in clinical protocols as recommended by the Food and Drug Administration (FDA) and the PharmGKB® for coumarin drugs. A previous genotypic analysis of the patient would have allowed reaching the therapeutic range sooner, thus avoiding potential bleeding risks. This shows the importance of pharmacogenetic analyses for highly variable treatments with a narrow therapeutic range. 相似文献
103.
Carly E. Martin Andrew S. Murray Kimberley E. Sala-Hamrick Jacob R. Mackinder Evan C. Harrison Joseph G. Lundgren Fausto A. Varela Karin List 《The Journal of biological chemistry》2021,297(4)
TMPRSS13, a member of the type II transmembrane serine protease (TTSP) family, harbors four N-linked glycosylation sites in its extracellular domain. Two of the glycosylated residues are located in the scavenger receptor cysteine-rich (SRCR) protein domain, while the remaining two sites are in the catalytic serine protease (SP) domain. In this study, we examined the role of N-linked glycosylation in the proteolytic activity, autoactivation, and cellular localization of TMPRSS13. Individual and combinatory site-directed mutagenesis of the glycosylated asparagine residues indicated that glycosylation of the SP domain is critical for TMPRSS13 autoactivation and catalytic activity toward one of its protein substrates, the prostasin zymogen. Additionally, SP domain glycosylation-deficient TMPRSS13 displayed impaired trafficking of TMPRSS13 to the cell surface, which correlated with increased retention in the endoplasmic reticulum. Importantly, we showed that N-linked glycosylation was a critical determinant for subsequent phosphorylation of endogenous TMPRSS13. Taken together, we conclude that glycosylation plays an important role in regulating TMPRSS13 activation and activity, phosphorylation, and cell surface localization. 相似文献
104.
Gonçalo S. Faria Susana A. M. Varela Andy Gardner 《Evolution; international journal of organic evolution》2017,71(3):526-540
Recent years have seen a surge of interest in linking the theories of kin selection and sexual selection. In particular, there is a growing appreciation that kin selection, arising through demographic factors such as sex‐biased dispersal, may modulate sexual conflicts, including in the context of male–female arms races characterized by coevolutionary cycles. However, evolutionary conflicts of interest need not only occur between individuals, but may also occur within individuals, and sex‐specific demography is known to foment such intragenomic conflict in relation to social behavior. Whether and how this logic holds in the context of sexual conflict—and, in particular, in relation to coevolutionary cycles—remains obscure. We develop a kin‐selection model to investigate the interests of different genes involved in sexual and intragenomic conflict, and we show that consideration of these conflicting interests yields novel predictions concerning parent‐of‐origin specific patterns of gene expression and the detrimental effects of different classes of mutation and epimutation at loci underpinning sexually selected phenotypes. 相似文献
105.
Filipe V. Duarte João A. Amorim Ana T. Varela João S. Teodoro Ana P. Gomes Rodrigo A. Cunha Carlos M. Palmeira Anabela P. Rolo 《Purinergic signalling》2017,13(2):179-190
Although adenosine A1 receptors (A1R) have been associated to ischemic preconditioning (IPC), direct evidence for their ability to preserve mitochondrial function upon hepatic preconditioning is still missing and could represent a novel strategy to boost the quality of liver transplants. We tested if the A1R antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) prevented IPC in the liver and if the A1R agonist 2-chloro-N6-cyclopentyladenosine (CCPA) might afford a pharmacological preconditioning. Livers underwent a 120 min of 70% warm ischemia and 16 h of reperfusion (I/R), and the IPC group underwent a 5-min ischemic episode followed by a 10-min period of reperfusion before I/R. DPCPX or CCPA was administered intraperitoneally 2 h before IPC or I/R. The control of mitochondrial function emerged as the central element affected by IPC and controlled by endogenous A1R activation. Thus, livers from IPC- or CCPA-treated rats displayed an improved oxidative phosphorylation with higher state 3 respiratory rate, higher respiratory control ratio, increased ATP content, and decreased lag phase. IPC and CCPA also prevented the I/R-induced susceptibility to calcium-induced mitochondrial permeability transition, the rate of reactive oxygen species (ROS) generation, and the decreased mitochondrial content of phospho-Ser9 GSK-3β. DPCPX abrogated these effects of IPC. These implicate the control of GSK-3β activity by Akt-mediated Ser9-GSK-3β phosphorylation preserving the efficiency of oxidative phosphorylation and ROS-mediated cell death in the ability of A1R activation to mimic IPC in the liver. In conclusion, the parallel between IPC and A1R-mediated preconditioning also paves the way to consider a putative therapeutic use of the later in liver transplants. 相似文献
106.
New targeted approaches for the quantification of data‐independent acquisition mass spectrometry
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Chih‐Chiang Tsou Alonso Barrantes‐Freer Christine Stadelmann Alexey I. Nesvizhskii Manuela Schmidt Lukas Reiter David Gomez‐Varela 《Proteomics》2017,17(9)
The use of data‐independent acquisition (DIA) approaches for the reproducible and precise quantification of complex protein samples has increased in the last years. The protein information arising from DIA analysis is stored in digital protein maps (DIA maps) that can be interrogated in a targeted way by using ad hoc or publically available peptide spectral libraries generated on the same sample species as for the generation of the DIA maps. The restricted availability of certain difficult‐to‐obtain human tissues (i.e., brain) together with the caveats of using spectral libraries generated under variable experimental conditions limits the potential of DIA. Therefore, DIA workflows would benefit from high‐quality and extended spectral libraries that could be generated without the need of using valuable samples for library production. We describe here two new targeted approaches, using either classical data‐dependent acquisition repositories (not specifically built for DIA) or ad hoc mouse spectral libraries, which enable the profiling of human brain DIA data set. The comparison of our results to both the most extended publically available human spectral library and to a state‐of‐the‐art untargeted method supports the use of these new strategies to improve future DIA profiling efforts. 相似文献
107.
Fernández V Tapia G Varela P Gaete L Vera G Mora C Vial MT Videla LA 《Free radical biology & medicine》2008,44(9):1724-1731
Hepatic ischemia-reperfusion (IR) injury, a major clinical drawback during surgery, is abolished by L-3,3',5-triiodothyronine (T(3)) administration. Considering that the triggering mechanisms are unknown, the aim of this study is to assess the role of oxidative stress in T(3) preconditioning using N-acetylcysteine (NAC) before T(3) administration. Male Sprague-Dawley rats given a single dose of 0.1 mg of T(3)/kg were subjected to 1 h ischemia followed by 20 h reperfusion, in groups of animals pretreated with 0.5 g of NAC/kg 0.5 h before T(3) or with the respective control vehicles. At the end of the reperfusion period, blood and liver samples were taken for analysis of serum aspartate aminotransferase (AST) and hepatic histology, glutathione (GSH) and protein carbonyl contents, and nuclear factor-kappaB (NF-kappaB) and activating protein 1 (AP-1) DNA binding. The IR protocol used led to a 4.5-fold increase in serum AST levels and drastic changes in liver histology, with significant GSH depletion and enhancement of protein carbonyl levels and of the protein carbonyl/GSH content ratio, whereas NF-kappaB and AP-1 DNA binding was decreased and enhanced, respectively. In a time window of 48 h, T(3) exerted protection against hepatic IR injury, with 88% reduction in the protein carbonyl/GSH ratio and normalization of NF-kappaB and AP-1 DNA binding, changes that were suppressed by NAC administration before T(3). Data presented suggest that a transient increase in the oxidative stress status of the liver is an important trigger for T(3) preconditioning, evidenced in a warm IR injury model through antioxidant intervention. 相似文献
108.
Suárez-Varela MM García-Marcos Alvarez L Kogan MD González AL Gimeno AM Aguinaga Ontoso I Díaz CG Pena AA Aurrecoechea BD Monge RM Quiros AB Garrido JB Canflanca IM Varela AL 《International journal of biometeorology》2008,52(8):833-840
Atopic eczema (AE) is a chronic skin disease. Recent reports indicate that the worldwide prevalence of AE is increasing and
that various environmental factors are implicated in its aetiology. Climatic conditions have been related with AE prevalence,
and Spain has varying climatic conditions. The aim of this study is to document the possible climatic influence on the prevalence
of AE in schoolchildren aged 6–7 years in three different climatic regions in Spain. We conducted a cross-sectional population-based
survey of 28,394 schoolchildren aged 6–7 years from 10 Spanish centres in three different climatic regions. The mean participation
rate was 76.5%. AE prevalence was assessed using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire
and the Spanish Academy of Dermatology criteria used in Spain to diagnose AE. The data, including annual temperature, precipitation,
relative humidity and the annual number of sunny hours per climatic region, were obtained from the Spanish National Institute
of Meteorology. Different AE prevalences were found in all three climatic regions studied: Atlantic, 32.9; Mediterranean 28.3;
and Continental 31.2 per 100 children studied (p < 0.005). AE was positively associated with precipitation and humidity, and was negatively associated with temperature and
the number of sunny hours. The results show that AE is significantly dependent on meteorological conditions. 相似文献
109.
Nélia Varela Louise Couton César Gemeno Jesús Avilla Jean-Pierre Rospars Sylvia Anton 《Cell and tissue research》2009,337(3):513-526
The oriental fruit moth Cydia molesta is an important pest and the behavioural role of olfactory signals such as pheromones and plant volatiles have been studied
extensively in both sexes. To understand odour processing further, however, detailed knowledge of the anatomy of the olfactory
system is crucial. In the present study, an atlas of the antennal lobe (AL) is presented based on the three-dimensional reconstructions
of both ALs of three male and three female brains by means of neuroanatomical and computational approaches. We identified
48–49 "ordinary" glomeruli and one large glomerulus situated at the entrance of the antennal nerve in males, and 49–52 "ordinary"
glomeruli and one large glomerulus in the ventro-medial part of the AL in females. Anomalous supernumerary, anomalous missing
and sexually dimorphic glomeruli were found in the studied individuals in greater numbers than in other lepidopteran species.
Male and female maps were compared with respect to glomerular size and position with 45 glomeruli being matched, indicating
a conserved glomerular pattern between the sexes. Three additional glomeruli were sexually dimorphic in size and five male-specific
and six female-specific glomeruli were also found. Palp backfills resulted in the staining of a unique glomerulus in both
sexes identified as the sexually dimorphic glomerulus 45. This glomerulus was never stained from antennal backfills, which
stained the other glomeruli of the AL. The three-dimensional atlas can now be used to elucidate the functional role of individual
glomeruli in both sexes of C. molesta.
Nélia Varela and Louise Couton contributed equally to this work.
This study was supported by research grants from INRA (Projet Jeune Equipe and Projet S.P.E.) to S.A. and J.P.R. and by the
Spanish Ministry of Science and Technology (research grant AGL2004-05812/AGR to J.A. and C.G., Spanish Science and Education
Department, MEC). N.V. was financed by fellowship no. BES-2005-7605 (MEC, Spain). 相似文献
110.
A putative multidrug efflux pump, EmrD-3, belonging to the major facilitator superfamily (MFS) of transporters and sharing
homology with the Bcr/CflA subfamily, was identified in Vibrio cholerae O395. We cloned the emrD-3 gene and evaluated its role in antimicrobial efflux in a hypersensitive Escherichia coli strain. The efflux activity of this membrane protein resulted in lowering the intracellular concentration of ethidium. The
recombinant plasmid carrying emrD-3 conferred enhanced resistance to several antimicrobials. Among the antimicrobials tested, the highest relative increase in
minimum inhibitory concentration (MIC) of 102-fold was observed for linezolid (MIC = 256 μg/ml), followed by an 80.1-fold
increase for tetraphenylphosphonium chloride (TPCL) (156.2 μg/ml), 62.5-fold for rifampin (MIC = 50 μg/ml), >30-fold for erythromycin
(MIC = 50 μg/ml) and minocycline (MIC = 2 μg/ml), 20-fold for trimethoprim (MIC = 0.12 μg/ml), and 18.7-fold for chloramphenicol
(MIC = 18.7 μg/ml). Among the fluorescent DNA-binding dyes, the highest relative increase in MIC of 41.7-fold was observed
for ethidium bromide (125 μg/ml) followed by a 17.2-fold increase for rhodamine 6G (100 μg/ml). Thus, we demonstrate that
EmrD-3 is a multidrug efflux pump of V. cholerae, the homologues of which are present in several Vibrio spp., some members of Enterobacteriaceae family, and Gram-positive Bacillus spp. 相似文献