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For years, we have relied on population surveys to keep track of regional public health statistics, including the prevalence of non-communicable diseases. Because of the cost and limitations of such surveys, we often do not have the up-to-date data on health outcomes of a region. In this paper, we examined the feasibility of inferring regional health outcomes from socio-demographic data that are widely available and timely updated through national censuses and community surveys. Using data for 50 American states (excluding Washington DC) from 2007 to 2012, we constructed a machine-learning model to predict the prevalence of six non-communicable disease (NCD) outcomes (four NCDs and two major clinical risk factors), based on population socio-demographic characteristics from the American Community Survey. We found that regional prevalence estimates for non-communicable diseases can be reasonably predicted. The predictions were highly correlated with the observed data, in both the states included in the derivation model (median correlation 0.88) and those excluded from the development for use as a completely separated validation sample (median correlation 0.85), demonstrating that the model had sufficient external validity to make good predictions, based on demographics alone, for areas not included in the model development. This highlights both the utility of this sophisticated approach to model development, and the vital importance of simple socio-demographic characteristics as both indicators and determinants of chronic disease.  相似文献   
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Marine heatwaves (MHWs) are emerging as a severe stressor in marine ecosystems. Extreme warm sea surface temperatures during MHWs often exceed the optimal thermal range for more than one generation of tropical coastal zooplankton. However, it is relatively unknown whether transgenerational plasticity (TGP) to MHWs may shape the offspring''s fitness, particularly in an ecologically relevant context with biotic interactions such as predation stress. We addressed these novel research questions by determining the survival, reproductive success, and grazing rate of the copepod Pseudodiaptomus incisus exposed to MHW and fish predator cues (FPC) for two generations (F1 and F2). The experiment was designed in a full orthogonal manner with 4 treatments in F1 and 16 treatments in F2 generation. In both generations, MHW reduced P. incisus survival, reproductive parameters, and grazing by 10%–62% in MHW, but these parameters increased by 2%–15% with exposure to FPC, particularly at control temperature. F2 reproductive success and grazing rate as indicated by cumulative fecal pellets were reduced by 20%–30% in F1‐MHW, but increased by ~2% in F1‐FPC. Strikingly, MHW exposure reduced 17%–18% survival, but transgenerational exposure to MHWs fully ameliorated its lethal effect and this transgenerational effect was independent of FPC. Increased survival came with a cost of reduced reproductive success, constrained by reduced grazing. The rapid transgenerational MHW acclimation and its associated costs are likely widespread and crucial mechanisms underlying the resilience of coastal tropical zooplankton to MHWs in tropical coastal marine ecosystems.  相似文献   
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The influence of P-supply on root system architecture (primary root length, number and total length of lateral roots) through the effects of ethylene (ACC) and auxin [1-naphthylacetic acid (NAA)] has been examined in the legume white clover (Trifolium repens L.). Higher concentrations (1 and 10 μM) of ACC and NAA (100 nM) inhibited growth, while lower concentrations (100 nM ACC, 5 nM NAA) either had no effect or stimulated growth in P-sufficient (1 mM Pi) roots. In response to low (10 μM) P, a stimulation of primary root growth, number of lateral roots and mean length of lateral roots was observed, while a super-stimulation of these growth parameters occurred in response to subsequent 100 nM ACC treatment suggesting that the low P treatment increased the sensitivity of the roots to ethylene. Examination of the primary roots of DR5p::GUS transformants suggests that this change in sensitivity induced by low P occurs through the promotion of auxin signalling/transport to the root apex. These results are discussed in terms of the role of ethylene and the significance of changes in sensitivity to the hormone in modulating root system architecture in response to low P-supply.  相似文献   
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Iodine and iron are essential elements for healthy thyroid function. However, little is known about the association of iron and iodine with thyroid function in the general US population. We investigated iron and iodine status in relation to concentrations of thyroid hormones. We included 7672 participants aged 20 and older from three surveys (2007–2008, 2009–2010, and 2011–2012) of the National Health and Nutrition Examination Survey. Serum thyroid measures (including free and total T3 and T4, and TSH), serum iron concentration, and urinary iodine concentrations were measured. Multivariate linear regression models were conducted with serum thyroid measures as dependent variables and combinations of serum iron concentration and urinary iodine concentration as predictors with covariate adjustment. Logistic regression models were performed with TSH levels (low, normal, and high) and combinations of serum iron concentration and urinary iodine concentration. Overall, 10.9% of the study population had low iron; 32.2 and 18.8% had low or high iodine levels, respectively. Compared with normal levels of iron and iodine, normal iron and high iodine were associated with reduced free T3 and increased risk of abnormal high TSH. Combined low iron and low iodine was associated with reduced free T3 and increased TSH. In addition, high iodine was associated with increased risk of abnormal high TSH in females but not in males. Thyroid function may be disrupted by low levels of iron or abnormal iodine, and relationships are complex and sex-specific. Large prospective studies are needed to understand the mechanisms by which iron interacts with iodine on thyroid function.  相似文献   
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Acinetobacter baumannii has received much attention owing to its exceptional ability to develop resistance to currently available antibiotics. Alanine racemase (ALR) catalyzes the racemization of L‐alanine to D‐alanine with pyridoxal 5′‐phosphate (PLP) as a cofactor. The D‐alanine product is an essential component of the bacterial cell wall and ALR is a potential target for the development of novel antibacterial drugs. The alr gene from A. baumannii was cloned and the protein (AbALR) was expressed, purified and crystallized. The AbALR crystal diffracted to 2.3 Å resolution and belonged to the primitive orthorhombic space group P212121, with unit‐cell parameters a = 55.1, b = 85.0, c = 167.7 Å. Two protomers were present in the asymmetric unit, with a corresponding VM value of 2.3 Å3 Da−1 and a solvent content of 47.5%.  相似文献   
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Plasma kallikrein kinin system (KKS) activation along with its cellular receptors expression are increased after injury and in patients with septic shock, hypotensive bacteremia and rhesus monkey infected with Salmonella typhimurium. KKS signaling cascade is activated by activated factor XII (FXIIa, Hageman factor)- and prolylcarboxypeptidase (PRCP)-dependent pathways on endothelial cells. Among the many entities that comprise the KKS, high molecular weight kininogen (HK), a bradykinin precursor, is critical in the assembly and activation of this system. HK is primarily expressed in the liver and secreted into the bloodstream. The activation of the KKS influences the permeability of the endothelium by liberating bradykinin (BK) from HK. BK is a potent inflammatory peptide which stimulates constitutive bradykinin B2 and inducible B1 receptors to release nitric oxide and prostacyclin. Regardless of the triggers, PK can only be activated on HK bound to the artificial negatively charged or to cell membrane surfaces. Since LPS has a negatively charged moiety and the ability to induce inflammatory responses in human, we determined the interaction between LPS and HK. HKH19 (HK cell binding site) and heparin inhibited LPS binding to HK with IC50s of 15 nM and 20 μg/ml, respectively. C1-inhibitor and N-acetylglucosamine glycan inhibited LPS binding to HK with IC50s of about 10 μg/ml and 10 mM, respectively. This novel study underscores the implication of HK in infection. We propose that HKH19, heparin, and C1-inhibitor present therapeutic potential for the treatment of sepsis and hypotensive bacteremia.  相似文献   
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Plasmonics - Since the metamaterial perfect absorber (MPA) is composed of electromagnetic resonance structures, the main operational mechanism of the MPA is electromagnetic resonance. In this work,...  相似文献   
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