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21.
We evaluated a new automated homogeneous PCR assay to detect toxigenic Clostridium difficile, the GenomEra C. difficile assay (Abacus Diagnostica, Finland), with 310 diarrheal stool specimens and with a collection of 33 known clostridial and nonclostridial isolates. Results were compared with toxigenic culture results, with discrepancies being resolved by the GeneXpert C. difficile PCR assay (Cepheid). Among the 80 toxigenic culture-positive or GeneXpert C. difficile assay-positive fecal specimens, 79 were also positive with the GenomEra C. difficile assay. Additionally, one specimen was positive with the GenomEra assay but negative with the confirmatory methods. Thus, the sensitivity and specificity were 98.8% and 99.6%, respectively. With the culture collection, no false-positive or -negative results were observed. The analytical sensitivity of the GenomEra C. difficile assay was approximately 5 CFU per PCR test. The short hands-on (<5 min for 1 to 4 samples) and total turnaround (<1 h) times, together with the high positive and negative predictive values (98.8% and 99.6%, respectively), make the GenomEra C. difficile assay an excellent option for toxigenic C. difficile detection in fecal specimens.  相似文献   
22.
Background: This paper systematically reviews the MEDLINE and SCOPUS literature to answer the following question: Is there any evidence that bruxism may cause periodontal damage per se? Methods: Clinical studies on humans, assessing the potential relationship between bruxism and periodontal lesions (i.e., decreased attachment level, bone loss, tooth mobility/migration, altered periodontal perception) were eligible. Methodologic shortcomings were identified by the adoption of the Critical Appraisal Skills Program quality assessment, mainly concerning the internal validity of findings according to an unspecific bruxism diagnosis. Results: The six included articles covered a high variability of topics, without multiple papers on the same argument. Findings showed that the only effect of bruxism on periodontal structures was an increase in periodontal sensation, whereas a relationship with periodontal lesions was absent. Based on the analysis of Hill criteria, the validity of causation conclusions was limited, mainly owing to the absence of a longitudinal evaluation of the temporal relationship and dose‐response effects between bruxism and periodontal lesions. Conclusions: Despite the scarce quantity and quality of the literature that prevents sound conclusions on the causal link between bruxism and the periodontal problems assessed in this review, it seems reasonable to suggest that bruxism cannot cause periodontal damage per se. It is also important to emphasize, however, that because of methodologic problems, particularly regarding sleep bruxism assessment, more high‐quality studies (e.g., randomized controlled trials) are needed to further clarify this issue.  相似文献   
23.
Working memory (WM) is the ability to retain and associate information over brief time intervals. Functional imaging studies demonstrate that WM is mediated by a distributed network including frontal and posterior cortices, hippocampus, and cerebellum. In rodents, the presentation of stimuli in a WM task is followed by a reset of the phase of hippocampal theta. In this paper we report the observation of a similar phenomenon in normal human subjects. Neuromagnetic responses were recorded during presentation of a set of digits and a subsequent probe of the retained items. All stimuli were presented with a fixed temporal pattern. We observed phase reset of approximately 7 Hz theta in left hippocampus approximately 120 ms after probe stimuli, whereas reset of theta in right hippocampus was visible approximately 80 ms prior to these anticipated stimuli. The duration of stimulus-locked theta increased with memory load, with a limiting value of approximately 600 ms for 5-7 retained items. We suggest that, as in rats, stimulus-locked theta may index involvement of human hippocampal networks in the cognitive processing of sensory input. The anticipatory phase reset of theta indicates involvement of hippocampus in right hemisphere and cerebellar timing networks. Hippocampal structures are essential for orientation to perturbations in the sensory scene, a function that requires use of a context established by a constellation of stimuli. We suggest that the initiation and maintenance of stimulus-locked hippocampal theta observed here may facilitate processing of potentially salient and/or novel input with respect to a context established by the contents of WM.  相似文献   
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25.
Accumulating evidence indicates that childhood nutrition plays a role in the adulthood cardiovascular health. A lifelong tracking of dietary habits, following a long-term exposure to unhealthy dietary patterns or independent effects, is a potential effect-mediating mechanism. Dietary patterns have been studied by data-driven and hypothesis-based approaches. Typically, either data-driven healthy or prudent childhood dietary patterns have been characterized and found to be associated with lower adulthood cardiovascular disease (CVD) risk in the published cohort studies. With regard to the individual food groups or food quality indices, intakes particularly of vegetables and fruits (or fiber indicating plant food intake) and polyunsaturated fatty acids have shown protective effects. The evidence which could confirm the long-term healthiness of a hypothesis-based Mediterranean diet is limited, requiring further investigation. Overall, the recent literature strengthens the view that a healthy childhood diet is associated with lowered adulthood CVD risk.  相似文献   
26.
Ameloblastoma is a benign but locally infiltrative odontogenic neoplasm. Although ameloblastomas rarely metastasise, recurrences together with radical surgery often result in facial deformity and significant morbidity. Development of non‐invasive therapies has been precluded by a lack of understanding of the molecular background of ameloblastoma pathogenesis. When addressing the role of ERBB receptors as potential new targets for ameloblastoma, we discovered significant EGFR over‐expression in clinical samples using real‐time RT–PCR, but observed variable sensitivity of novel primary ameloblastoma cells to EGFR‐targeted drugs in vitro. In the quest for mutations downstream of EGFR that could explain this apparent discrepancy, Sanger sequencing revealed an oncogenic BRAF V600E mutation in the cell line resistant to EGFR inhibition. Further analysis of the clinical samples by Sanger sequencing and BRAF V600E‐specific immunohistochemistry demonstrated a high frequency of BRAF V600E mutations (15 of 24 samples, 63%). These data provide novel insight into the poorly understood molecular pathogenesis of ameloblastoma and offer a rationale to test drugs targeting EGFR or mutant BRAF as novel therapies for ameloblastoma. Published by John Wiley & Sons, Ltd. www.pathsoc.org.uk  相似文献   
27.
Polypyrrole (PPy) is a conductive polymer that has aroused interest due to its biocompatibility with several cell types and high tailorability as an electroconductive scaffold coating. This study compares the effect of hyaluronic acid (HA) and chondroitin sulfate (CS) doped PPy films on human adipose stem cells (hASCs) under electrical stimulation. The PPy films were synthetized electrochemically. The surface morphology of PPy–HA and PPy–CS was characterized by an atomic force microscope. A pulsed biphasic electric current (BEC) was applied via PPy films non-stimulated samples acting as controls. Viability, attachment, proliferation and osteogenic differentiation of hASCs were evaluated by live/dead staining, DNA content, Alkaline phosphatase activity and mineralization assays. Human ASCs grew as a homogenous cell sheet on PPy–CS surfaces, whereas on PPy–HA cells clustered into small spherical structures. PPy–CS supported hASC proliferation significantly better than PPy–HA at the 7 day time point. Both substrates equally triggered early osteogenic differentiation of hASCs, although mineralization was significantly induced on PPy–CS compared to PPy–HA under BEC. These differences may be due to different surface morphologies originating from the CS and HA dopants. Our results suggest that PPy–CS in particular is a potential osteogenic scaffold coating for bone tissue engineering.  相似文献   
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29.

Aims/hypothesis

We validated the metabolic syndrome (MetS) score by confirmatory factor analysis (CFA) in children, middle-aged men, and older women and men and by investigating the relationships of the MetS score to incident type 2 diabetes, myocardial infarction, and cardiovascular and overall death in middle-aged men.

Methods

We assessed the core features of MetS, calculated the MetS score using z scores for waist circumference, insulin, glucose, triacylglycerols, HDL-cholesterol and blood pressure, and carried out CFA to investigate whether MetS represents a single entity in population samples of 491 children, 1,900 middle-aged men, 614 older women and 555 older men from Finland. We also followed-up incident type 2 diabetes for 11 years and other outcomes for 17–18 years in middle-aged men.

Results

We carried out second-order CFAs in which the MetS was represented by a second-order latent variable underlying four latent variables characterised by abdominal obesity, insulin resistance, dyslipidaemia and raised blood pressure in different age groups. These second-order factors and factors derived from first-order CFA using previously proposed models were strongly associated with a composite MetS score in all age groups (r?=?0.84–0.94) and similarly predicted type 2 diabetes, cardiovascular outcomes and mortality in middle-aged men. The risk of type 2 diabetes, myocardial infarction, cardiovascular death and overall death increased 3.67-, 1.38-, 1.56- and 1.44-fold, respectively, for a 1 SD increase in the MetS score.

Conclusions

The MetS can be described as a single entity in all age groups. The MetS score is a valid tool for research evaluating cardiometabolic risk in different age groups. Further research is needed to define cut-off points for risk estimation in clinical practice.  相似文献   
30.
Emotions are often felt in the body, and somatosensory feedback has been proposed to trigger conscious emotional experiences. Here we reveal maps of bodily sensations associated with different emotions using a unique topographical self-report method. In five experiments, participants (n = 701) were shown two silhouettes of bodies alongside emotional words, stories, movies, or facial expressions. They were asked to color the bodily regions whose activity they felt increasing or decreasing while viewing each stimulus. Different emotions were consistently associated with statistically separable bodily sensation maps across experiments. These maps were concordant across West European and East Asian samples. Statistical classifiers distinguished emotion-specific activation maps accurately, confirming independence of topographies across emotions. We propose that emotions are represented in the somatosensory system as culturally universal categorical somatotopic maps. Perception of these emotion-triggered bodily changes may play a key role in generating consciously felt emotions.We often experience emotions directly in the body. When strolling through the park to meet with our sweetheart we walk lightly with our hearts pounding with excitement, whereas anxiety might tighten our muscles and make our hands sweat and tremble before an important job interview. Numerous studies have established that emotion systems prepare us to meet challenges encountered in the environment by adjusting the activation of the cardiovascular, skeletomuscular, neuroendocrine, and autonomic nervous system (ANS) (1). This link between emotions and bodily states is also reflected in the way we speak of emotions (2): a young bride getting married next week may suddenly have “cold feet,” severely disappointed lovers may be “heartbroken,” and our favorite song may send “a shiver down our spine.”Both classic (3) and more recent (4, 5) models of emotional processing assume that subjective emotional feelings are triggered by the perception of emotion-related bodily states that reflect changes in the skeletomuscular, neuroendocrine, and autonomic nervous systems (1). These conscious feelings help the individuals to voluntarily fine-tune their behavior to better match the challenges of the environment (6). Although emotions are associated with a broad range of physiological changes (1, 7), it is still hotly debated whether the bodily changes associated with different emotions are specific enough to serve as the basis for discrete emotional feelings, such as anger, fear, or happiness (8, 9), and the topographical distribution of the emotion-related bodily sensations has remained unknown.Here we reveal maps of bodily sensations associated with different emotions using a unique computer-based, topographical self-report method (emBODY, Fig. 1). Participants (n = 701) were shown two silhouettes of bodies alongside emotional words, stories, movies, or facial expressions, and they were asked to color the bodily regions whose activity they felt to be increased or decreased during viewing of each stimulus. Different emotions were associated with statistically clearly separable bodily sensation maps (BSMs) that were consistent across West European (Finnish and Swedish) and East Asian (Taiwanese) samples, all speaking their respective languages. Statistical classifiers discriminated emotion-specific activation maps accurately, confirming independence of bodily topographies across emotions. We propose that consciously felt emotions are associated with culturally universal, topographically distinct bodily sensations that may support the categorical experience of different emotions.Open in a separate windowFig. 1.The emBODY tool. Participants colored the initially blank body regions (A) whose activity they felt increasing (left body) and decreasing (right body) during emotions. Subjectwise activation–deactivation data (B) were stored as integers, with the whole body being represented by 50,364 data points. Activation and deactivation maps were subsequently combined (C) for statistical analysis.  相似文献   
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