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671.
Diabetic patients show a high susceptibility to oral diseases of inflammatory, catabolic and chronic nature with potential impact on saliva composition. In this study, our purpose was to characterize type 1 diabetes‐induced alterations in the salivary peptidome aiming to find prospective biomarkers for type 1 diabetes oral health evaluation. Peptidomic analysis of saliva from controls (n = 5) and type 1 diabetic patients (n = 5) were performed by liquid chromatography followed by mass spectrometry. The proteolytic activity and metalloproteinases expression was accessed by zymography and slot blot analysis, respectively. Data evidenced a significant increase in the percentage of peptides in diabetic patients paralleled by a higher proteolytic activity, compared with healthy individuals. The nonsalivary gland protein fragments identified in saliva were mainly derived from collagen and extracellular matrix proteins, namely collagen type I. The cleavage site frequency analysis showed significant differences between healthy and type 1 diabetic individuals, highlighting the activity of proteases such as matrix metalloproteinase‐9 and cathepsin D. Our results highlight salivary collagen fragments as potential biomarkers to follow up diabetes‐related oral damage. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
672.
The growing consumer demand for food with sensory quality and nutritional has called for research to develop new products with consumer acceptance as cookies made from flaxseed meal, that can be inserted in diet of celiacs. Celiac disease characterized by an inappropriate immune response to dietary proteins found in wheat, rye and barley (gluten and gliadin). It can affect anyone at any age and is more common in women. The celiac disease does not have cure and the only scientifically proven treatment is a gluten free diet. Irradiation as a decontamination method used for a many variety of foodstuffs, being very feasible, useful method to increase the shelf life, effective and environmental friendly without any sensory properties significant change. Sensory analyses were used to assess gluten-free bakery foods subjected to ionizing radiation sensory attributes.  相似文献   
673.
Worldwide Brazil is among one of the 22 countries with high rates of tuberculosis placing this disease as a priority for the Government Health Policies in this country. Studies with the main tuberculostatic drugs rifampicin, isoniazid, pyrazinamide, and ethambutol, aiming the development of fixed-dose combination formulations (FDCs) have been performed. The aim of this study was to evaluate the thermal behavior of these drugs by DSC, TG/DTG, and DTA in order to predict possible physical and chemical interactions between tuberculostatics. DSC and DTA curves suggested incompatibility and/or interactions among drug preparations resulting from new thermal events, as well as the disappearance and shift of the melting point of the drugs. TG/DTG curves of drug mixtures presented different profiles from those observed for the individually tested drugs, supporting the evidence of drug incompatibility and indicating that mixtures are less stable when compared to the drugs alone.  相似文献   
674.
This work reports the synthesis of new fatty N-acylamino acids and N-acylamino esters from the C16:0, C18:0, C18:1, and C18:1(OH) fatty acid families and demonstrates the activity of these compounds as organogel agents. Compounds were heated and dissolved in various solvents (n-hexane, toluene, and gasoline). Only saturated C16:0 and C18:0 derived from alanine were able to form gels in toluene, and saturated C16:0 derived from phenylalanine showed gelation in n-hexane. This is the first evidence that fatty N-acylamino esters and N-acylamino acid derivatives of l-serine and fatty acids C16:0, C18:0, and C18:1 are able to form gels with hexane. This observation confirms the importance of the hydroxyl group in the segment derivative of l-serine in forming good gels.  相似文献   
675.
Protein precipitation with TCA followed by acetone washing is frequently used to clean samples before 2-DE. However, the difficulty in solubilizing TCA-precipitated proteins causes some variability in 2-D gels and makes it difficult to detect some proteins. In this work we show that sonication of the samples, after TCA precipitation followed by elution in sample buffer, increases total protein recovery, and improves reproducibility and matching ratios between gels when analyzed by specialized software.  相似文献   
676.
Effects of participant-target distance and perceived handstriking efficiency on emergent behavior in the martial art of boxing were investigated, revealing affordance-controlled nonlinear dynamical effects (i.e. bifurcations) within the participant--target system. Results established the existence of critical values of scaled distances for emergence of first time excitations and annihilations of a diverse range of boxing actions i.e. on the appearance and dissolution of jabs, hooks and uppercuts. Reasons for the action diversity were twofold: (a) topological discontinuous changes (bifurcations) in the number of possible handstrikes, i.e. motor solutions to the hitting task; (b) fine modification of probabilities of emergence of striking patterns. Exploitation of a 'strikeability' affordance available in scaled distance-to-target information by boxers led to a diversity of emergent actions through a cascade of bifurcations in the task perceptual-motor work space. Data suggested that perceived efficiency (E) of an action changed as a function of scaled distance (D) and was correlated with the probability of occurrence of action patterns (P), exhibiting the following dependence P = P(E(D)). The implication is that probability of occurrence (P) depends on efficiency (E), which in turn depends on scaled distance (D) to the target. Accordingly, scaled distance-dependent perceived efficiency seems a viable candidate for a contextual (control) parameter to describe the nonlinear dynamics of striking actions in boxing.  相似文献   
677.
OBJECTIVES: This study aimed to characterize the prevalence of congenital heart disease (CHD) in children born alive in S?o Miguel island from January 1992 to December 2001. METHODS: Based on the Azorean Registry of CHD, which includes complete clinical and personal information, 189 patients were diagnosed. RESULTS: During this 10-year period, the average prevalence of CHD is 9.16 per 1,000 live births (range 4.77-12.75). The most frequent cardiac malformations found were: ventricular septal defect (38.1%), atrial septal defect (12.2%) and patent ductus arteriosus (11.6%). Until now, four familial clusters were identified, representing a total of 13 patients. CONCLUSIONS: This first epidemiological study of CHD in the Azorean population reveals evidence for familial aggregation, which is of great interest for understanding the genes involved in these complex pathologies.  相似文献   
678.
Rainwater is a very low concentrated matrix and, for dissolved organic matter (DOM) characterization, an efficient extraction procedure is essential. Isolation procedures based on the adsorption onto XAD-8 and C-18 sorbents have been used in the literature for rainwater DOM isolation, but a comparison between these procedures is lacking. In this work, UV-visible and molecular fluorescence spectroscopies highlighted differences between rainwater DOM isolated by DAX-8 (replacement for XAD-8) and by C-18. It was possible to recover higher rainwater DOM percentage by the C-18 based procedure than by the DAX-8 one. Rainwater protein-like compounds were better concentrated by the C-18 procedure than by the DAX-8 one, while humic-like compounds were similarly concentrated by both procedures. Furthermore, rainwater DOM extracted by the C-18 procedure was more representative of the global matrix, while DAX-8 preferentially extracted humic-like compounds.  相似文献   
679.
Here is described the preparation of four new rhodium(II) complexes bearing axial NHC ligands. The presence of electron-withdrawing bridging ligands resulted in an enhanced reactivity in the arylation of aldehydes with boronic acids when compared with the tetraacetate counterparts. Complex 15 (Rh2tfa4(IPr)2) proved to be the most active catalyst for this transformation allowing the selective conversion of aromatic, aliphatic and vinyl aldehydes into the respective alcohols in excellent yields. It was demonstrated that the good group tolerance could be further extended to aromatic and conjugated ketones. DFT calculations carried out on this system showed the complementarily of the bridging ligands and axial ligand in these dinuclear complexes. It was also disclosed that Rh(II)/NHC catalytic system can promote the racemization of 1-phenyl ethanol.  相似文献   
680.
When can an (n-k)×(n-k) normal matrix B be imbedded in an n×n normal matrix A? This question was studied for the first time 50 years ago by Ky Fan and Gordon Pall, who gave the complete answer in the case k=1. Since then, a few authors obtained additional results. In this note, we show how an approach inspired by the Hermitian case can throw some light on the problem.  相似文献   
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