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91.
Three copper(ii) tetraaza complexes [Cu(ii)LBr]Br (1a), [Cu(ii)L(CIO4)](CIO4) (2a) and [Cu(ii)L](CIO4)2 (2b), where L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-7,14-diene were prepared and confirmed by FTIR, 1HNMR and 13CNMR. The binding interaction of complex (1a, 2a, 2b) with calf thymus DNA (CT-DNA) was investigated using UV-vis absorption, luminescence titrations, viscosity measurements and molecular docking. The findings suggested that complex 1a, 2a and 2b bind to DNA by electrostatic interaction, and the strengths of the interaction were arranged according to 2b > 1a > 2a. The differences in binding strengths were certainly caused by the complexes'' dissimilar charges and counter anions. Complex 2b, with the biggest binding strength towards the DNA, was further applied in developing the porcine sensor. The developed sensor exhibits a broad linear dynamic range, low detection limit, good selectivity, and reproducibility. Analysis of real samples showed that the biosensor had excellent selectivity towards the pork meat compared to chicken and beef meat.

The electrochemical biosensor of porcine using copper(ii) tetraaza complex gave excellent performance with a broad dynamic range, low detection limit, good selectivity and reproducibility. The biosensor could sensitively detect pork DNA in real meat samples.  相似文献   
92.
A low temperature alkali (LTA) pretreatment method was used to treat wheat straw. In order to obtain good results, different factors like temperature, incubation time, NaOH concentration and solid to liquid ratio for the pretreatment process were optimized. Wheat straw is a potential biomass for the production of monomeric sugars. The objective of the current study was to observe the saccharification (%) of wheat straw with immobilized magnetic nanoparticles (MNPs). For this purpose, immobilized MNPs of purified β-xylanase enzyme was used for hydrolysis of pretreated wheat straw. Wheat straw was pretreated using the LTA method and analyzed by SEM analysis. After completion of the saccharification process, saccharification% was calculated by using a DNS method. Scanning electron micrographs revealed that the hemicellulose, cellulose and lignin were partially removed and changes in the cell wall structure of the wheat straw had caused it to become deformed, increasing the specific surface area, so more fibers of the wheat straw were exposed to the immobilized β-xylanase enzyme after alkali pretreatment. The maximum saccharification potential of wheat straw was about 20.61% obtained after pretreatment with optimized conditions of 6% NaOH, 1/10 S/L, 30 °C and 72 hours. Our results indicate the reusability of the β-xylanase enzyme immobilized magnetic nanoparticles and showed a 15% residual activity after the 11th cycle. HPLC analysis of the enzyme-hydrolyzed filtrate also revealed the presence of sugars like xylose, arabinose, xylobiose, xylotriose and xylotetrose. The time duration of the pretreatment has an important effect on thermal energy consumption for the low-temperature alkali method.

A low temperature alkali (LTA) pretreatment method was used to treat wheat straw.  相似文献   
93.
In recent years, there has been a resurgence of interest in developing green and renewable alternate energy sources as a solution to the energy and environmental problems produced by conventional fossil fuel use. As a very effective energy transporter, hydrogen (H2) is a possible candidate for the future energy supply. Hydrogen production by water splitting is a promising new energy option. Strong, efficient, and abundant catalysts are required for increasing the efficiency of the water splitting process. Cu-based materials as an electrocatalyst have shown promising results for application in the Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) in water splitting. In this review, our aim is to cover the latest developments in the synthesis, characterisation, and electrochemical behaviour of Cu-based materials as a HER, and OER electrocatalyst, highlighting the impact that these advances have had on the field. It is intended that this review article will serve as a roadmap for developing novel, cost-effective electrocatalysts for electrochemical water splitting based on nanostructured materials with particular emphasis on Cu-based materials for electrocatalytic water splitting.

In recent years, there has been a resurgence of interest in developing green and renewable alternate energy sources as a solution to the energy and environmental problems produced by conventional fossil fuel use.  相似文献   
94.
Environmental pollution, climate change, and fossil fuel extinction have aroused serious global interest in the search for alternative energy sources. The dry reforming of methane (DRM) could be a good technique to harness syngas, a starting material for the FT energy process from greenhouse gases. Noble metal DRM catalysts are effective for the syngas generation but costly. Therefore, they inevitably, must be replaced by their Ni-based contemporaries for economic reasons. However, coking remains a strong challenge that impedes the industrialization of the FT process. This article explains the secondary reactions that lead to the production of detrimental graphitic coke deposition on the surface of active nickel catalyst. The influence of nickel particle size, impact of extra surface oxygen species, interaction of Ni catalysts with metal oxide supports/promoters, and larger fraction of exposed nickel active sites were addressed in this review. Size of active metal determines the conversion, surface area, metal dispersion, surface reactions, interior diffusion effects, activity, and yield. The influence of oxygen vacancy and coke deposition on highly reported metal oxide supports/promoters (Al2O3, MgO and La2O3) was postulated after studying CIFs (crystallographic information files) obtained from the Crystallography open database (COD) on VESTA software. Thus, overcoming excessive coking by La2O3 promotion is strongly advised in light of the orientation of the crystal lattice characteristics and the metal–support interaction can be used to enhance activity and stability in hydrogen reforming systems.

Particle size increases during agglomeration, which causes catalyst deactivation. Reducible metal oxide restricts metal growth, hence reducing the sintering.  相似文献   
95.
Viruses produce more viruses by manipulating the metabolic and replication systems of their host cells. Many have acquired metabolic genes from ancestral hosts and use the encoded enzymes to subvert host metabolism. The polyamine spermidine is required for bacteriophage and eukaryotic virus replication, and herein, we have identified and functionally characterized diverse phage- and virus-encoded polyamine metabolic enzymes and pathways. These include pyridoxal 5′-phosphate (PLP)-dependent ornithine decarboxylase (ODC), pyruvoyl-dependent ODC and arginine decarboxylase (ADC), arginase, S-adenosylmethionine decarboxylase (AdoMetDC/speD), spermidine synthase, homospermidine synthase, spermidine N-acetyltransferase, and N-acetylspermidine amidohydrolase. We identified homologs of the spermidine-modified translation factor eIF5a encoded by giant viruses of the Imitervirales. Although AdoMetDC/speD is prevalent among marine phages, some homologs have lost AdoMetDC activity and have evolved into pyruvoyl-dependent ADC or ODC. The pelagiphages that encode the pyruvoyl-dependent ADCs infect the abundant ocean bacterium Candidatus Pelagibacter ubique, which we have found encodes a PLP-dependent ODC homolog that has evolved into an ADC, indicating that infected cells would contain both PLP- and pyruvoyl-dependent ADCs. Complete or partial spermidine or homospermidine biosynthetic pathways are found encoded in the giant viruses of the Algavirales and Imitervirales, and in addition, some viruses of the Imitervirales can release spermidine from the inactive N-acetylspermidine. In contrast, diverse phages encode spermidine N-acetyltransferase that can sequester spermidine into its inactive N-acetyl form. Together, the virome-encoded enzymes and pathways for biosynthesis and release or biochemical sequestration of spermidine or its structural analog homospermidine consolidate and expand evidence supporting an important and global role of spermidine in virus biology.

The polyamine spermidine (Fig. 1) is a metabolically primordial polycation found throughout bacteria, archaea, and eukaryotes (1). It is a fundamental molecule of life that was likely present in the last universal common ancestor (2). In Escherichia coli, 90% of spermidine is noncovalently bound to RNA (3) and is required for efficient translational elongation by the ribosome (4). Spermidine increases global messenger RNA (mRNA) translation in E. coli by facilitating the queuosine modification of specific tRNA anticodon wobble bases (4). Consistent with these findings, in strains of E. coli deleted for genes that modify the anticodon wobble position in transfer RNAs (tRNAs), spermidine becomes absolutely essential for growth (5), which may be due to spermidine-mediated stabilization of the tRNA interaction with the translating ribosome. Spermidine is not only important for growth of bacteria; over 40 y ago, it was shown that T4 and T7 bacteriophages replicated more slowly in a spermidine-deficient mutant of E. coli (6). Replication of JG004 and N4-like phages in Pseudomonas aeruginosa PAO1 is absolutely dependent on spermidine (7, 8).Open in a separate windowFig. 1.Polyamine metabolic pathways. Pathways biochemically characterized herein are indicated by blue arrows and blue enzyme names.In eukaryotic cells, spermidine is universally required for growth and cell proliferation. An aminobutyl moiety of spermidine (Fig. 1) is transferred by deoxyhypusine synthase (DHS) to a single lysine of the translation factor eIF5A to eventually form the essential hypusine posttranslational modification (9). Hypusinated eIF5a is needed for translation of mRNAs encoding proline-rich motifs and for translation termination (10). Replication of eukaryotic RNA viruses is highly dependent on host spermidine (11), and spermidine-derived hypusination of host eIF5a is required for Ebola virus replication and is considered a potential target to inhibit viral replication (12).Viruses reprogram the metabolism of host cells to make more virions by redirecting expression and activity of host-encoded enzymes and by expressing virus-encoded enzymes. Using homology-based approaches, nucleocytoplasmic large DNA viruses have been found to encode homologs of enzymes involved in nitrogen metabolism, glycolysis, and the tricarboxylic acid cycle (13). Bacteriophages have been found to encode homologs of enzymes involved in inorganic sulfur metabolism (14) and nucleotide metabolism (15). The eukaryotic chlorovirus Paramecium bursaria chlorella virus 1 (PBCV-1) encodes an entire functional biosynthetic pathway for production of homospermidine (Fig. 1), a structural analog of spermidine, consisting of L-arginine decarboxylase (ADC), agmatine deiminase/iminohydrolase (AIH), N-carbamoylputrescine amidohydrolase (NCPAH), and homospermidine synthase (HSS) (1618). In addition, PBCV-1 encodes a polyamine N-acetyltransferase (19). A biochemically functional HSS enzyme is encoded by Ralstonia phage ϕRSL1 (20). Considering the importance of polyamines to phage and virus replication, we sought to systematically identify and functionally characterize polyamine metabolic enzymes and pathways encoded in phage and virus genomes. Some of the taxonomic affiliations of giant viruses included in our study are based on a recently published hierarchical taxonomy for the Nucleocytoviricota (21).  相似文献   
96.
Interest towards cellulose nanofibers obtained from virgin and waste sources has seen a significant growth, mainly thanks to the increasing sensitivity towards the concept of circular economy and the high levels of paper recycling achieved in recent years. Inspired by the guidelines of the green building industry, this study proposes the production and characterization of TEMPO-oxidized and homogenized cellulose nanofibers (TOHO CNF) from different sources and their use as additives for earth plasters on two different raw earth samples, characterized by geotechnical laboratory tests and mineralogical analysis: a high-plasticity clay (T2) and a medium-compressibility silt (ABS). Original sources, including those derived from waste (recycled cardboard and paper mill sludge), were characterized by determining chemical content (cellulose versus ashes and lignin) and fiber morphology. TOHO CNF derived from the different sources were compared in terms of nanofibers medium diameter, crystallinity degree, thermal decomposition and oxidation degree, that is the content of carboxylic groups per gram of sample. Then, a preliminary analysis of the influence of CNF on earth plasters is examined. Adhesion and capillary absorption tests highlighted the effect of such nanofibers on blends in function of two factors, namely the cellulose original source and the oxidation degree of the fibers. In particular, for both earth samples, T2 and ABS, a significant increase in adhesion strength was observed in the presence of some TOHO CNF additives. As far as capillary sorption tests, while an undesired increase in water adsorption was detected for T2 compared to the control, in the case of ABS, a significant reduction in water content was measured by adding TOHO CNF derived from recycled sources. These results pave the way for further in-depth investigation on the role of TOHO CNF as additives for earth plasters.  相似文献   
97.
Depression is a neuropsychiatric disorder associated with persistent stress and disruption of neuronal function. Persistent stress causes neuronal atrophy, including loss of synapses and reduced size of the hippocampus and prefrontal cortex. These alterations are associated with neural dysfunction, including mood disturbances, cognitive impairment, and behavioral changes. Synaptic plasticity is the fundamental function of neural networks in response to various stimuli and acts by reorganizing neuronal structure, function, and connections from the molecular to the behavioral level. In this review, we describe the alterations in synaptic plasticity as underlying pathological mechanisms for depression in animal models and humans. We further elaborate on the significance of phytochemicals as bioactive agents that can positively modulate stress-induced, aberrant synaptic activity. Bioactive agents, including flavonoids, terpenes, saponins, and lignans, have been reported to upregulate brain-derived neurotrophic factor expression and release, suppress neuronal loss, and activate the relevant signaling pathways, including TrkB, ERK, Akt, and mTOR pathways, resulting in increased spine maturation and synaptic numbers in the neuronal cells and in the brains of stressed animals. In clinical trials, phytochemical usage is regarded as safe and well-tolerated for suppressing stress-related parameters in patients with depression. Thus, intake of phytochemicals with safe and active effects on synaptic plasticity may be a strategy for preventing neuronal damage and alleviating depression in a stressful life.  相似文献   
98.
IntroductionWe aimed to compare perioperative and postoperative outcomes and to assess the safety and feasibility of same-day trial of void (TOV) in patients who underwent standard holmium laser enucleation of the prostate (HoLEP) vs. MOSESTM HoLEP (MoLEP).MethodsWe conducted a retrospective review of prospectively collected data of patients that underwent HoLEP (100 W) or MoLEP (120 W) with same-day catheter removal three hours postoperatively at our institution from August 2018 to September 2021. Patient demographics, intraoperative parameters, and postoperative outcomes were analyzed. Data were compared as means with standard deviation and medians with interquartile range (IQR) or numbers and percentages. Continuous and categorical variables were assessed using the Mann-Whitney U test and Chi-squared test, respectively. Predictors of shorter enucleation time and failed same-day TOV were investigated.ResultsOf the 90 patients included, 28 underwent HoLEP while 62 had MoLEP. There was no significant difference between the groups in terms of the successful TOV (23 [82%] vs. 58 [93.5%], p=0.1) and readmission rate (3 [10.7%] vs. 1 [1.6%], p=0.08); however, the MoLEP group had a significantly shorter mean enucleation time (p<0.001), mean hemostasis time (p<0.001), mean morcellation time (p=0.003), and lower mean energy used (p<0.001). On the logistic regression model, MoLEP (odds ratio [OR] 0.03, 95% confidence interval [CI] 0.007–0.19, p<0.001), lower preoperative prostate-specific antigen (PSA) test (OR 1.25, 95% CI 1.01–1.55, p=0.03), and smaller prostate size (OR 1.06, 95% CI 1.02–1.09, p<0.001) were independent predictors of shorter enucleation time. History of preoperative retention was the only significant factor associated with a failed same-day TOV (p=0.04). There was no difference in intraoperative or postoperative complication rates or postoperative functional outcomes between the two technologies.ConclusionsSame-day TOV and discharge are feasible following standard HoLEP and MoLEP, with comparable outcomes; however, the use of MOSESTM technology offered better enucleation efficiency with excellent hemostatic potential. Preoperative retention was the only predictor of failed same-day TOV.  相似文献   
99.
A healthy eating environment in the school setting is crucial to nurture the healthy eating pattern for youth. Thus, it helps to combat the obesity issue. However, the impact of healthy school environment on healthy eating habits among Asian adolescents is scarce and less clear. This clustered randomised-control study has two objectives. The first objective was to evaluate the changes in adolescents’ dietary intake after the interventions for all arms (control; healthy cooking training only; subsidization with healthy cooking training). The second objective was to compare the effect of subsidization with healthy cooking training and healthy cooking training only with the control arm on adolescents’ dietary intakes. This study consisted of 340 secondary school students aged 14 years in rural and urban Malaysia. A total of two arms of intervention and one arm of control were included. Intervention one focused on healthy cooking preparation for the canteen and convenience shop operators. Intervention two included subsidization for fruits and vegetables with a healthy cooking preparation training for the canteen and suggestions on providing healthy options to the convenience shop operators. The outcome measured was changes to dietary intake. It was measured using a three-day dietary history pre- and post-intervention. A paired-t test was used to evaluate the outcome of intervention programmes on dietary changes for all arms (control, intervention one and two). An ANCOVA test was used to investigate the effect of providing subsidization and healthy cooking preparation training to the canteen and convenience shop operators on adolescents’ dietary intakes as compared to the control arm. Overall, the reduction in energy and carbohydrates for all arms were observed. Interestingly, fat intake was significantly increased after the four-week intervention programme under healthy cooking intervention but not in the food subsidization group. When comparing between control, healthy cooking training only and subsidization with the healthy cooking training arm, there was no significant changes between arms. A robust intervention to include subsidization of healthy foods for intervention programmes at schools in a larger scale study is needed to confirm this finding.  相似文献   
100.
In neonates, bilirubin tends to be deposited in body tissues, especially the skin and mucous membranes. Jaundice is an early symptom of bilirubin excretion disorders. Therefore, the aim of this study was to investigate the effect of clofibrate on reducing neonatal jaundice. In this systematic review, international databases, including PubMed, Scopus, Web of Science, Embase, Cochrane, and Google Scholar, were searched without time and language restrictions. The reference lists of all studies ultimately included were manually searched. In the 17 articles reviewed, with a sample size of 665 people published between 2005 and 2019, the average weight of the neonates varied from 2,186 g to 4,000 g. Furthermore, the average age of neonates varied from 2 days to 9 days. Four doses of clofibrate (25, 30, 50, 100 mg/kg of neonatal body weight) were used. The bilirubin level of neonates significantly decreased in the intervention group 24, 36, 48, and 72 hours after the start of treatment. Clofibrate administration decreased total serum bilirubin, especially from the second day onwards, and also reduced hospitalization time, hospital costs, and side effects from hospitalization.  相似文献   
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