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991.
In recent years, phenolic acids have received considerable attention as they are essential to olive oil quality and nutritional properties. This study aims to validate a rapid and sensitive method based on ultra‐performance liquid chromatography/time‐of‐flight mass spectrometry (UPLC–TOF‐MS) for analyzing the phenolic acid content of olive oil and assessing its impact on virgin olive oil (VOO) sensory attributes. Once this method was validated, we used it to evaluate the phenolic acid composition of several Spanish monovarietal virgin olive oils in relation to nine different olive ripening stages. The results obtained confirm that the methodology developed in this study is valid for extracting and analyzing phenolic acids from VOO. The phenolic acid content of the virgin olive oils sampled was proven to be influenced by the type of cultivar and olive harvest date. Therefore, phenolic acids might be used as potential markers for olive oil cultivar or ripening stage. Finally, the data obtained indicate that the sensory properties of VOO may be differently affected by its phenolic acid content depending on the type of cultivar. Practical applications: The method validated in the present study – based on UPLC‐TOF‐MS – allows experts to assess the phenolic acid content of different VOO cultivars (varieties). This application will probably be very useful to the olive oil industry. The reason is that our study revealed that phenolic acids have an impact on the sensory quality of VOO, which is essential to consumer preferences and choice. In addition, there are phenolic acids that are only found in a particular variety of olive oil obtained from fruits at a specific ripening stage. Consequently, phenolic acids could be used as potential markers for olive oil variety and harvest time.  相似文献   
992.
This article reports an amperometric glucose biosensor based on a new type of nanocomposite of polypyrrole (PPY) with p-phenyl sulfonate-functionalized single-walled carbon nanotubes (SWCNTs-PhSO3). An environmentally friendly functionalization procedure of the SWCNTs in the presence of substituted aniline and an oxidative species was adopted. The nanocomposite-modified electrode exhibited excellent electrocatalytic activities towards the reduction or oxidation of H2O2. This feature allowed us to use it as bioplatform on which glucose oxidase (GOx) was immobilized by entrapment in an electropolymerized PPY/SWCNTs-PhSO3 film for the construction of the glucose biosensor. The amperometric detection of glucose was assayed by applying a constant electrode potential value necessary to oxidize or reduce the enzymatically produced H2O2 with minimal interference from the possible coexisting electroactive compounds. With the introduction of a thin film of Prussian blue (PB) at the substrate electrode surface, the PPY/GOx/SWCNTs-PhSO3/PB system shows synergy between the PB and functionalized SWCNTs which amplifies greatly the electrode sensitivity when operated at low potentials. The biosensor showed good analytical performances in terms of low detection (0.01 mM), high sensitivity (approximately 6 μA mM−1 cm−2), and wide linear range (0.02 to 6 mM). In addition, the effects of applied potential, the electroactive interference, and the stability of the biosensor were discussed. The facile procedure of immobilizing GOx used in the present work can promote the development of other oxidase-based biosensors which could have a practical application in clinical, food, and environmental analysis.  相似文献   
993.
The effect of methyl jasmonate postharvest application on the antioxidant and anti-inflammatory activity of strawberry fruits was evaluated. Results showed that the methyl jasmonate treated strawberry extract had higher antioxidant activity and suppresses the nitrite production in LPS-stimulated RAW 264.7 murine macrophages. The HPLC profiles of both treated and untreated strawberry extracts were compared. To evaluate which compounds are responsible of these higher activities it was also investigated the antioxidant and anti-inflammatory capacities of the hexane, chloroform, EtOAc, and n-butanol fractions obtained from the methyl jasmonate treated strawberry. The EtOAc and n-butanol fractions exhibited the most potent antioxidant activity compared to the hexane and chloroform fractions. In addition the n-butanol fraction was able to decrease nitrite production. The EtOAc and n-butanol fractions were analyzed by LC–MS. These results showed that methyl jasmonate promotes antioxidant and anti-inflammatory capacity of strawberry fruits by the stimulation of phenolic compounds and anthocyanins production.  相似文献   
994.
The increased frequency and magnitude of natural disasters is producing a growing awareness of the need to incorporate mental well-being and resilience into policy and practice. The present research uses mental well-being impact assessment (MWIA) to identify and describe the main factors enhancing mental well-being of people affected by a tsunami on Robinson Crusoe Island in 2010, and explores their effects on people's resilience. The main factors were: the natural environment, meaningful activities, local food, social activities, lifelong learning, transport and security. These factors influenced mental well-being through four main environmental dimensions: ecology, culture, milieu and organization. They could influence mental well-being in a constant, multiple and cumulative way. The findings of this research provide a significant practical knowledge for the improvement of MWIA practice.  相似文献   
995.
996.
Penile cancer (PeC) is a rare disease, and no prognostic biomarkers have been adopted in clinical practice yet. The objective of the present study was to identify differentially expressed miRNAs (DEmiRs) and genes (DEGs) as potential biomarkers for lymph node metastasis and other prognostic factors in PeC. Tumor samples were prospectively obtained from 24 patients with squamous cell carcinoma of the penis. miRNA microarray analysis was performed comparing tumors from patients with inguinal lymph node metastatic and localized disease, and the results were validated by qRT-PCR. Eighty-three gene expression levels were also compared between groups through qRT-PCR. Moreover, DEmiRs and DEGs expression levels were correlated with clinicopathological variables, cancer-specific (CSS), and overall survival (OS). TAC software, TM4 MeV 4.9 software, SPSS v.25.0, and R software v.4.0.2 were used for statistical analyses. We identified 21 DEmiRs in microarray analysis, and seven were selected for validation. miR-744-5p and miR-421 were overexpressed in tissue samples of metastatic patients, and high expression of miR-421 was also associated with lower OS. We found seven DEGs (CCND1, EGFR, ENTPD5, HOXA10, IGF1R, MYC, and SNAI2) related to metastatic disease. A significant association was found between increased MMP1 expression and tumor size, grade, pathological T stage, and perineural invasion. Other genes were also associated with clinicopathological variables, CSS and OS. Finally, we found changes in mRNA–miRNA regulation that contribute to understanding the mechanisms involved in tumor progression. Therefore, we identified miRNA and mRNA expression profiles as potential biomarkers associated with lymph node metastasis and prognosis in PeC, in addition to disruption in mRNA–miRNA regulation during disease progression.  相似文献   
997.
A significant portion of the world’s plastic is not properly disposed of and, through various processes, is degraded into microscopic particles termed micro- and nanoplastics. Marine and terrestrial faunae, including humans, inevitably get in contact and may inhale and ingest these microscopic plastics which can deposit throughout the body, potentially altering cellular and molecular functions in the nervous and other systems. For instance, at the cellular level, studies in animal models have shown that plastic particles can cross the blood–brain barrier and interact with neurons, and thus affect cognition. At the molecular level, plastics may specifically influence the folding of proteins, induce the formation of aberrant amyloid proteins, and therefore potentially trigger the development of systemic and local amyloidosis. In this review, we discuss the general issue of plastic micro- and nanoparticle generation, with a focus on their effects on protein folding, misfolding, and their possible clinical implications.  相似文献   
998.
The number of people that are 65 years old or older has been increasing due to the improvement in medicine and public health. However, this trend is not accompanied by an increase in quality of life, and this population is vulnerable to most illnesses, especially to infectious diseases. Vaccination is the best strategy to prevent this fact, but older people present a less efficient response, as their immune system is weaker due mainly to a phenomenon known as immunosenescence. The adaptive immune system is constituted by two types of lymphocytes, T and B cells, and the function and fitness of these cell populations are affected during ageing. Here, we review the impact of ageing on T and B cells and discuss the approaches that have been described or proposed to modulate and reverse the decline of the ageing adaptive immune system.  相似文献   
999.
Genetic variants in gene-encoding proteins involved in cell–cell connecting structures, such as desmosomes and gap junctions, may cause a skin and/or cardiac phenotype, of which the combination is called cardiocutaneous syndrome. The cardiac phenotype is characterized by cardiomyopathy and/or arrhythmias, while the skin particularly displays phenotypes such as keratoderma, hair abnormalities and skin fragility. The reported variants associated with cardiocutaneous syndrome, in genes DSP, JUP, DSC2, KLHL24, GJA1, are classified by interpretation guidelines from the American College of Medical Genetics and Genomics. The genotype–phenotype correlation, however, remains poorly understood. By providing an overview of variants that are assessed for a functional protein pathology, we show that this number (n = 115) is low compared to the number of variants that are assessed by in silico algorithms (>5000). As expected, there is a mismatch between the prediction of variant pathogenicity and the prediction of the functional effect compared to the real functional evidence. Aiding to improve genotype–phenotype correlations, we separate variants into ‘protein reducing’ or ‘altered protein’ variants and provide general conclusions about the skin and heart phenotype involved. We conclude by stipulating that adequate prognoses can only be given, and targeted therapies can only be designed, upon full knowledge of the protein pathology through functional investigation.  相似文献   
1000.
Critical limb ischemia (CLI) is a severe manifestation of peripheral artery disease characterized by ischemic pain, which is frequently associated with diabetes and non-healing lesions to inferior limbs. The clinical management of diabetic patients with CLI typically includes percutaneous transluminal angioplasty (PTA) to restore limb circulation and surgical treatment of diabetic foot ulcers (DFU). However, even after successful treatment, CLI patients are prone to post-procedure complications, which may lead to unplanned revascularization or foot surgery. Unfortunately, the factors predicting adverse events in treated CLI patients are only partially known. This study aimed to identify potential biomarkers that predict the disease course in diabetic patients with CLI. For this purpose, we measured the circulating levels of a panel of 23 molecules related to inflammation, endothelial dysfunction, platelet activation, and thrombophilia in 92 patients with CLI and DFU requiring PTA and foot surgery. We investigated whether these putative biomarkers were associated with the following clinical endpoints: (1) healing of the treated DFUs; (2) need for new revascularization of the limb; (3) appearance of new lesions or relapses after successful healing. We found that sICAM-1 and endothelin-1 are inversely associated with DFU healing and that PAI-1 and endothelin-1 are associated with the need for new revascularization. Moreover, we found that the levels of thrombomodulin and sCD40L are associated with new lesions or recurrence, and we show that the levels of these biomarkers could be used in a decision tree to assign patients to clusters with different risks of developing new lesions or recurrences.  相似文献   
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