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81.
Translating the timing of brain developmental events across mammalian species using suitable models has provided unprecedented insights into neural development and evolution. More importantly, these models can prove to be useful abstractions and predict unknown events across species from known empirical event timing data retrieved from published literature. Such predictions can be especially useful since the distribution of the event timing data is skewed with a majority of events documented only across a few selected species. The present study investigates the choice of single hidden layer feed-forward neural networks (FFNN) for predicting the unknown events from the empirical data. A leave-one-out cross-validation approach is used to determine the optimal number of units in the hidden layer and the decay parameter for the FFNN. It is shown that unlike the present Finlay-Darlington (FD) model, FFNN does not impose any constraints on the functional form of the model and falls under the class of semiparametric regression models that can approximate any continuous function. The results from FFNN as well as FD model also indicate that a majority of events with large absolute prediction errors correspond to those of primates and late events comprising the tail of event timing data distribution with minimal representation in the empirical data. These results also indicate that accurate prediction of primate events may be challenging.  相似文献   
82.
The increase in crop productivity is an urgent need of the time to reduce scarcity of food in underdeveloped countries. Several biological, chemical and physical methods have been applied to promote crop yield. Application of magnetic field (MF) is an emerging physical method used to increase plant growth and yield. The reports on MF pretreatment-induced nutritional changes in harvested seeds are scarce. We previously identified the optimal frequency of MF to improve plant growth and yield as 1500 nT at 10.0 Hz. This study was aimed to investigate the effect of MF treatment on storage proteins and fatty acids in harvested soybean seeds. The results showed that MF triggered globulin production and suppressed prolamin production. However, lipid content in seeds increased, because MF exposure caused an elevation of several fatty acids including caprylic acid, palmitic acid, heptadecanoic acid, linoleic acid, lignoceric acid and eicosapentaenoic acid. This is the first report to reveal the seed pretreated MF on nutritional values of harvested seeds. This study suggests that MF treatment improves seed quality by regulating the metabolism of storage proteins and fatty acids.  相似文献   
83.
ABSTRACT

Conservation biological control is an approach to enhance the efficacy of natural enemies by ensuring their availability in an agro-ecosystem on a long temporal scale. An increased survival often leads to better fecundity and improved behaviour of the natural enemies, which in turn ensures sustainable pest management. This paper, apart from being a concise review of conservation biological control, deals with selected India-specific case studies and field experiences on habitat manipulation and refugia. Results from a Bengaluru-based study during 2012–2015 on conservation biological control in an organic mango ecosystem are also presented. It also dwells briefly on conservation of insectivorous birds and touches upon conservation biocontrol with respect to entomopathogenic microorganisms and plant disease antagonists.  相似文献   
84.
A new series of 1,4-dihydropyridine derivatives (2a–h, 3a–e, and 4a–e) were systematically designed and synthesized via ultrasound irradiation methods with easy work-up and good yields. Compounds structures were confirmed by IR, 1H NMR, 13C NMR, and mass spectra. The synthesized compounds were screened for both antimicrobial and anticoagulant activities. Compound 2e (MIC: 0.25?μg/mL) was highly active against Escherichia coli and compound 2c (MIC: 0.5?μg/mL) was also highly active against Pseudomonas aeruginosa compared with ciprofloxacin. (MIC: 1?μg/mL) The antifungal activity of 2c (MIC: 0.5?μg/mL) against Candida albicans was high relative to that of clotrimazole (MIC: 1?μg/mL). Anticoagulant activity was determined by activated partial thromboplastin time (APTT) and prothrombin time (PT) coagulation assays. Compound 4-(4-hydroxyphenyl)-2,6-dimethyl-N3,N5-bis(5-phenyl-1,3,4-thiadiazol-2-yl)-1,4-dihydropyridine-3,5-dicarboxamide 3d (>1000?s in APTT assays) was highly active in anticoagulant screening compared with the reference of heparin.Cytotoxicity was evaluated using HepG2 (liver), HeLa (cervical), and MCF-7 (breast) cancer cell lines, with high toxicities observed for 2c (GI50?=?0.02?μm) against HeLa cell line and 2e (GI50?=?0.03?μm) equipotant against MCF-7 cell line. Therefore, the compounds 2e, 2c and 3d can serve as lead molecules for the development of new classes of antimicrobial and anticoagulant agent.  相似文献   
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Bloom syndrome (BS) is a rare genetic disorder characterized by genomic instability and a high predisposition to cancer. The gene defective in BS, BLM, encodes a member of the RecQ family of 3′–5′ DNA helicases, and is proposed to function in recombinational repair during DNA replication. Here, we have utilized single‐molecule fluorescence resonance energy transfer microscopy to examine the behaviour of BLM on forked DNA substrates. Strikingly, BLM unwound individual DNA molecules in a repetitive manner, unwinding a short length of duplex DNA followed by rapid reannealing and reinitiation of unwinding in several successions. Our results show that a monomeric BLM can ‘measure’ how many base pairs it has unwound, and once it has unwound a critical length, it reverses the unwinding reaction through strand switching and translocating on the opposing strand. Repetitive unwinding persisted even in the presence of hRPA, and interaction between wild‐type BLM and hRPA was necessary for unwinding reinitiation on hRPA‐coated DNA. The reported activities may facilitate BLM processing of stalled replication forks and illegitimately formed recombination intermediates.  相似文献   
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89.
Dissolved organic matter (DOM) in seawater can be defined as the fraction of organic matter that passes through a filter of sub micron pore size. In this study, we have examined the effect of DOM of deep seawater (DSW) from Pacific Ocean on platelet aggregation and atherosclerosis progression. DSW was passed through a series of filters and then through an Octadecyl C18 filter; the retained substance in ethanol was designated as C18 extractable DOM (C18-DOM). Our studies showed that C18-DOM treatment inhibited platelet aggregation, P-selectin expression and activity of COX-1 significantly. C18-DOM increased the expression of anti-atherogenic molecule namely heme oxygenase-1 in endothelial cells and all these data showed that C18-DOM is exhibiting aspirin-like effects. Moreover our in vivo studies showed that C18-DOM feeding slowed remarkably the progression of atherosclerosis. Our study demonstrated a novel biological effect of oceanic DOM, which has several important implications, including a possible therapeutic strategy for atherosclerosis.  相似文献   
90.
An investigation was undertaken to evaluate a set of cyanobacterial strains in terms of production of biocidal compounds exhibiting allelochemical and fungicidal properties. Two cyanobacterial strains — Anabaena sp. and Calothrix sp. were selected for further investigation, on the basis of their larger inhibition zones on the lawn of Synechocystis and Synechococcus sp. and two phytopathogenic fungi — Rhizoctonia bataticola and Pythium debaryanum. The diameter of the inhibition zone was largest when extracellular filtrates of the two cultures incubated at high light intensity (90–100 μmol photons m−2 s−1) and temperature (40 ± 2 °C) or grown in medium containing two-folds higher P (1.4 mg/L, as compared to 0.7 mg/L in BG 11 medium) were taken. A pH of 8 was the most optimal for both strains, in terms of growth and biocidal activity. Partial purification of ethyl acetate extract using TLC, followed by GLC revealed a single peak. This study highlights the importance of environmental factors in aggravating or reducing the toxic effects of these harmful cyanobacteria and their potential as a biocontrol agent.  相似文献   
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