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551.
552.

The Two-Armed Bernoulli Bandit (TABB) problem is an orthodox optimization dilemma in reinforcement learning discipline where a decision-maker or agent is repeatedly faced with a choice of two actions (options). Every time the agent selects an action, it receives a corresponding payoff from an unknown distribution. Thus, the agent must trade-off between exploration of new better action and exploitation of current best action. Content retrieval in Named Data Networks (NDN) commences with a consumer requesting the desired content by sending an Interest that hits multiple content sources over different paths. As the corresponding Interest arrives, the content sources respond by replying the matching Data to the requester. In this work, Data replying problem in NDN is considered a TABB problem, denoted as DTABB. Since numerous sources are available, a content source in DTABB can choose between responding with entire content and partial content once the corresponding Interest strikes. The best source is trained to answer with complete data, while other (sub-optimal) sources learn to react with partial (or payload-free) data. The proposed strategy is formulated from a source’s viewpoint, which uses four prominent reinforcement learning algorithms: greedy, ε-greedy, Upper Confidence Bound (UCB1), and Gradient Bandit to select the optimal action. Eventually, the network picture converges to a point where a single source is exploited for whole data while others send only partial data. Thus, DTABB can substantially reduce the transmission overhead and enjoy a better user experience in terms of delay. DTABB is implemented in ndnSIM, which reveals that the proposed solution can reduce the communication overhead by up to 40% compared to the default strategy.

  相似文献   
553.

Salinity restricts plant growth and production by specific ions toxicity to particular plants. Cl ion is exceptionally toxic to citrus. Citrus rootstock and scion has a significant effect on each other under unfavourable conditions. Nevertheless, their specific response can be different depending on the way to translocate and compartment the toxic ions, or to induce antioxidant systems. In this paper, we studied the behaviour of diploid (2x) and tetraploid (4x) Volkamer lemon rootstocks grafted with commercial cultivar Kinnow mandarin (KM/VM2x and KM/VM4x, respectively) when exposed to moderate (75 mM) and high salt stress (150 mM). Both genotypes showed a decrease in their photosynthetic variables (Pn, gs, E, Fv/Fm, Fv′/Fm′, NPQ), and the decline was more significant in KM/VM2x plants as compared to KM/VM4x. The highest increase in the concentration of stress indicators (MDA and H2O2) was observed in leaves and roots of KM/VM2x at 75 and 150 mM of salt stress. The KM/VM4× showed the maximum increase in antioxidative enzymes (SOD, CAT, POD, APx, GR) and osmolytes (PRO, GB) in leaves and roots at 75 and 150 mM. Minerals (Cl ion, Na, K, P, N, Ca) accumulation was also significantly affected in leaves and roots of KM/VM2x and KM/VM4x under moderate and high NaCl stress. Overall, our results showed that Cl ion accumulation presents a robust correlation with stress indicators and their scavenging enzymes in leaves and roots. Moreover, 2x scion significantly mitigated by the 4x rootstock and showed more tolerance as compared to grafted on 2x rootstock.

  相似文献   
554.
Journal of Plant Growth Regulation - Plant-derived smoke (PDS) is an emerging area of interest for research in plant growth during stress conditions. Two wheat varieties (NARC 2011 and NARC 2009)...  相似文献   
555.
Journal of Plant Growth Regulation - Sustainable crop production under changing climate is crucial to feed the increasing population of the world. Efforts are underway to discover novel strategies...  相似文献   
556.
557.

Background

Saudi Arabia has a non-Saudi workers population. We investigated the differences and similarities of expatriate non-Saudi patients (NS) and Saudi nationals (SN) presenting with acute coronary syndromes (ACS) with respect to therapies and clinical outcomes.

Methods

The study evaluated 2031 of the 5055 ACS patients enrolled in the Saudi Project for Assessment of Acute Coronary Syndrome (SPACE) from 2005 to 2007. Propensity score matching and logistic regression analysis were performed to account for major imbalances in age and sex in the two groups.

Results

The mean patient age was 56.2±9.8, and 83.5% of the study cohort were male. SN were more likely to have risk factors of atherosclerosis. ST-elevation MI (STEMI) was the most common ACS presentation in NS, while non-ST ACS was more common in SN. The median symptom-to-door time was significantly greater in NS patients (Median 175 min (197) vs. 130 min (167), p=0.027). The only difference in pharmacological therapies between the two groups was that NS were more likely to receive fibrinolytic therapy. NS were less likely than SN to undergo percutaneous coronary interventions (PCI; 32.6% vs. 42.8%, p=0.0001) or primary PCI (7.8% vs. 22.8%, p<0.001). Hospital mortality, cardiogenic shock, and heart failure were significantly higher in NS compared to SN. After adjusting for baseline variables and therapies, the odds ratios for hospital mortality and cardiogenic shock in NS were 2.9 (95% CI 1.5–6.2, p=0.004) and 2.8 (95% CI 1.5–4.9, p<0.001), respectively.

Conclusion

Our findings indicate disparities in hospital care between NS and SN ACS patients. NS patients had worse hospital outcomes, which may reflect unequal health coverage and access-to-care issues.  相似文献   
558.
The two-dimensional boundary layer flow and heat transfer to Sisko nanofluid over a non-linearly stretching sheet is scrutinized in the concerned study. Our nanofluid model incorporates the influences of the thermophoresis and Brownian motion. The convective boundary conditions are taken into account. Implementation of suitable transformations agreeing with the boundary conditions result in reduction of the governing equations of motion, energy and concentration into non-linear ordinary differential equations. These coupled non-linear ordinary differential equations are solved analytically by using the homotopy analysis method (HAM) and numerically by the shooting technique. The effects of the thermophoresis and Brownian motion parameters on the temperature and concentration fields are analyzed and graphically presented. The secured results make it clear that the temperature distribution is an increasing function of the thermophoresis and Brownian motion parameters and concentration distribution increases with the thermophoresis parameter but decreases with the Brownian motion parameter. To see the validity of the present work, we made a comparison with the numerical results as well as previously published work with an outstanding compatibility.  相似文献   
559.
A novel folic acid functionalized terbium‐doped dendritic fibrous nanoparticle (Tb@KCC‐1‐NH2‐FA) with high surface area was synthesized using a novel hydrothermal protocol. In the present work, we report the fluorescent Tb‐doted nanomaterial with emission wavelength at 497 nm which confirms the formation of Tb@KCC‐1‐NH2‐FA. Synthesized nanoparticles were investigated through transmission electron microscope, field emission scanning electron Microscopy, Fourier transform infrared spectra, Brunauer‐Emmett‐Teller, energy dispersive X‐ray, Zeta potential and particle size distribution values and AFM (Atomic force microscopy) techniques. Specially, our desired nanomaterial which has FA moieties on the surface of Tb@KCC‐1‐NH2‐FA where interact with folate receptor (FR) which there is on the surface of the various cancer cells. For this purpose, fluorescence microscopy images were used to prove the uptake of FA based nanomaterial with FR‐positive MDA breast cancer and HT 29 colon cancer cells. Also HEK 293 normal cells as FR‐negative cells verified the specificity of our desired nanomaterial toward the FR‐positive cells. The cytotoxicity survey of Tb@KCC‐1‐NH2‐FA was examined by MTT assays against MDA breast cancer, HT 29 colon cancer and HEK 293 Normal cell lines which confirmed their biocompatible nature with any significant cytotoxic effects even for concentration higher than 900 μg/mL which could be used as a non‐toxic catalyst or carrier in biological ambient. Hence, Tb@KCC‐1‐NH2‐FA were synthesized using green and hydrothermal method; the process was simple with good productivity and desired nanocomposite was non‐toxic.  相似文献   
560.
Cultivated cotton (Gossypium hirsutum) is the most important fibre crop in the world. Cotton leaf curl disease (CLCuD) is the major limiting factor and a threat to textile industry in India and Pakistan. All the local cotton cultivars exhibit moderate to no resistance against CLCuD. In this study, we evaluated an exotic cotton accession Mac7 as a resistance source to CLCuD by challenging it with viruliferous whiteflies and performing qPCR to evaluate the presence/absence and relative titre of CLCuD‐associated geminiviruses/betasatellites. The results indicated that replication of pathogenicity determinant betasatellite is significantly attenuated in Mac7 and probably responsible for resistance phenotype. Afterwards, to decipher the genetic basis of CLCuD resistance in Mac7, we performed RNA sequencing on CLCuD‐infested Mac7 and validated RNA‐Seq data with qPCR on 24 independent genes. We performed co‐expression network and pathway analysis for regulation of geminivirus/betasatellite‐interacting genes. We identified nine novel modules with 52 hubs of highly connected genes in network topology within the co‐expression network. Analysis of these hubs indicated the differential regulation of auxin stimulus and cellular localization pathways in response to CLCuD. We also analysed the differential regulation of geminivirus/betasatellite‐interacting genes in Mac7. We further performed the functional validation of selected candidate genes via virus‐induced gene silencing (VIGS). Finally, we evaluated the genomic context of resistance responsive genes and found that these genes are not specific to A or D sub‐genomes of G. hirsutum. These results have important implications in understanding CLCuD resistance mechanism and developing a durable resistance in cultivated cotton.  相似文献   
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