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81.
Attentional bias to threat has proven a robust phenomenon in adults but has shown to be less stable in children. This study investigated whether a generally slow response speed may potentially obscure the effects of threat upon attention in children. Three non-clinical samples of different age (children, adolescents, young adults) performed an emotional modification of the spatial cueing task. Attentional bias was examined by comparing cueing effects by fear-conditioned cues (CS+) and neutral cues (CS−). Overall, analyses showed no biased attention to threat, and no differences between age groups could be detected. Further analyses indicated that the inability to demonstrate attentional bias to threat in the present study was due to the large response speed variability in our sample. Quintile analyses of the reaction times revealed that an overall attentional bias to threat across all groups was present when only the fast reaction times were taken into account. Methodological implications for measuring attentional bias in young age groups are discussed.  相似文献   
82.
A re-evaluation is made of the k0-factor and related nuclear data for the 555.8 keV gamma-ray of the 104mRh-104Rh mother–daughter pair that are important in neutron activation analysis (NAA). This study considers that the relevant level is also fed by the 4.34 min 104mRh mother (with an absolute gamma-ray emission probability γ2=0.13%) and not only, as assumed in former work, by the 42.3 s 104Rh daughter isotope (with γ3=2.0%). In view of this, generalised equations were developed for both the experimental determination and the analytical use of the k0-factor and of the associated parameters k0(m)/k0(g), Q0(m) and Q0(g) [(m):104mRh; (g): 104Rh], requiring the introduction of the γ2 and γ3 data and also of the 104mRh→104Rh fractional decay factor F2(=0.9987). The experimental determinations were based on irradiations performed in the BR1 reactor in Mol and the WWR-M reactor in Budapest. Furthermore, considering the special formation of the 555.8 keV gamma-ray, the procedure for true-coincidence correction was revised as well. All this led to the compilation and recommendation of a new set of ‘k0-NAA’ data.  相似文献   
83.
Post-steroid septic arthritis can be treated with irrigation pump assisted arthroscopic synovectomy. The high-intra-articular fluid pressures can force the pyogenic fluid into a pre-existing Baker’s cyst. The cyst can rupture and with the pre-existing steroid induced immune-suppression, the calf abscess will be hard to control. Therefore, thorough investigation with an ultrasound-guided aspiration followed by an early drainage of the collection is warranted and mandatory. Close monitoring for the development of a deep thrombosis of the popliteal vein is required.  相似文献   
84.
Gall-bladder visualization on oral cholecystography (OCG) is required for most non-surgical therapies of gallstones. In this study we attempted to establish sonographic criteria which will predict non-visualization of the gall-bladder on OCG. For this purpose we compared the results of ultrasound (US) and OCG in 171 patients with gallstones being assessed for non-surgical therapy. Sonographic criteria for non-visualization were a contracted gall-bladder and stone impaction in the gall-bladder neck or cystic duct. In detecting findings which predict non-visualization on OCG, US had a sensitivity of 78.3% and a specificity of 97.6%. The predictive values were: positive findings 92.3% and negative findings 92.4%. The overall accuracy was 92.4%. We conclude that US can be used as a first step in selecting patients for non-surgical therapy and if US indicates a contracted gall-bladder, 11% of the patients can be excluded from further diagnostic imaging.  相似文献   
85.
Chronic low back pain (CLBP) has major public health implications, and underlying mechanisms are still unclear. Sensorimotor incongruence (SMI)—an ongoing mismatch between top-down motor output and predicted sensory feedback—may play a role in the course of chronic nonspecific low back pain. The hypothesis of this study was that the induction of SMI causes sensory disturbances and/or pain in people with CLBP and healthy volunteers. A sample of 66 people (33 people with CLBP and 33 healthy volunteers) participated in a visual feedback experiment involving real-time images of their own lower backs—either during movement or in a static position—provided via a live video feed. Experimental SMI was induced via distorting visual feedback of the lower back during movement. There were no significant differences in sensory disturbances or pain intensity between experimental SMI and the other movement conditions in people with CLBP and healthy volunteers (P > .05). Static visual feedback had a significant effect on the intensity of sensory disturbances in people with CLBP (P?=?.038) and healthy volunteers (P < .001). In conclusion, experimental SMI did not affect sensory disturbances or pain in either group. Therefore, the research hypothesis was not supported.

Perspective

The results of this study show that sensorimotor incongruence does not cause additional symptoms and pain in people with chronic low back pain. The conceptual premise that sensorimotor incongruence is an underlying contributor in the course of pain in this population is not supported.  相似文献   
86.
The validity domain of voxel-based statistical analysis of SPECT neuroactivation studies with statistical parametric mapping (SPM) has been investigated by a limited number of theoretical and simulation studies. In this work, an experimental setup is described with an assessment of its activation detection performance together with the influence of acquisition and processing parameters. A subresolution sandwich phantom was constructed using a printed high-resolution digital Hoffman phantom with a (99m)TcO(4)-ink mixture. Activations of 8, 16, and 24 mm diameter, with an intensity ranging from 5 to 60%, were constructed in the right frontal cortex, anterior and posterior cingulate, and left striatum. Triple-headed SPECT acquisitions were carried out using both fan-beam and parallel beam geometry. The impact of activation characteristics (size, intensity and location), study size, physical degradation factors, and reconstruction technique were studied using SPM99 in a group comparison design with correction for multiple comparisons. For a 15 x 15 design, all 24-mm activations of 5% intensity were detected for the fan-beam data. Decreased focus or study size, lower SPECT resolution, absence of scatter, and attenuation correction resulted in an increase in minimally detectable activation. For a single study referred to 15 control studies, only 24-mm activation foci with a minimal intensity of 10% were detected in the optimal configuration. This approach allows experimental parameter optimization of SPM-based group or single-subject SPECT activation studies compared to normal data, as used in clinical applications. In principle, these findings can be extended to SPECT receptor studies or PET data.  相似文献   
87.
OBJECTIVES: To investigate aspects of the validity of the total scores of the Tampa Scale for Kinesiophobia (TSK), Dutch Version, which was modified to make it an appropriate questionnaire for the assessment of kinesiophobia (fear of movement) in chronic fatigue syndrome (CFS) patients (the Dutch TSK-CFS), and, using this assessment tool, to examine the associations between kinesiophobia, exercise capacity, and activity limitations and participation restrictions in patients with CFS. DESIGN: Prospective observational studies. SETTING: An outpatient fatigue clinic. PARTICIPANTS: In the first study, 40 patients fulfilling the 1994 US Centers for Disease Control and Prevention (CDC) criteria for CFS were enrolled. The sample of the second study consisted of 51 CDC-defined patients with CSF. INTERVENTIONS: Not applicable.Main outcome measures Study 1: Subjects completed a set of questionnaires; the Utrechtse Coping List (UCL), the Dutch TSK-CFS, and the Dutch Baecke Questionnaire of Habitual Physical Activity. Study 2: All patients completed 2 questionnaires (Chronic Fatigue Syndrome Activities and Participation Questionnaire [CFS-APQ], Dutch TSK-CFS) and performed a maximal exercise stress test on a bicycle ergometer. The heart rate was monitored continuously by use of an electrocardiograph. Metabolic and ventilatory parameters were measured through spirometry. RESULTS: Study 1: The Cronbach alpha coefficient for the individual item scores on the TSK-CFS was .80. The total scores on the Dutch TSK-CFS showed a statistically significant correlation with both the avoidance/abide subscale of the UCL (Spearman rho=.35, P=.029) and the total score of the Baecke Questionnaire (rho=-.45, P=.004). Study 2: The total scores on the Dutch TSK-CFS showed a statistically significant correlation with the total scores on the CFS-APQ (rho=.39, P=.004). No statistically significant associations were observed between the exercise capacity parameters and the total scores on the Dutch TSK-CFS. CONCLUSIONS: These results provide evidence for the internal consistency and the convergent and congruent validity of the scores obtained by use of the Dutch TSK-CFS. Kinesiophobia appears to be associated with activity limitations/participation restrictions but not with exercise capacity in patients with CFS.  相似文献   
88.

Background

Insomnia is a highly prevalent and debilitating comorbidity that is often not addressed in therapy for chronic spinal pain (CSP). Given the close interaction between insomnia and CSP severity and related disability, targeting sleep problems during therapy could improve treatment outcomes in these patients.

Objective

Can cognitive behavioral therapy for insomnia (CBT-I) combined with the modern neuroscience approach (i.e. pain neuroscience education and cognition-targeted exercise therapy) reduce pain and improve sleep, physical activity and function in people with CSP and comorbid insomnia?

Methods

Participants: One-hundred-twenty participants with chronic spinal pain and comorbid insomnia Intervention: CBT-I combined with the modern neuroscience approach (experimental) compared to the modern neuroscience approach alone (control). Both interventions start with three sessions of pain neuroscience education, followed by six sessions of CBT-I and nine sessions of cognition-targeted exercise therapy in the experimental group, or 15 sessions of cognition-targeted exercise therapy in the control group.

Measurements

Primary outcome measure: self-reported pain severity (Brief Pain Inventory). Secondary outcome measures: pain sensitivity (pressure pain thresholds, and online questionnaires), sleep-related outcomes (home-based polysomnography and online questionnaires), physical activity (actigraphy), and function (online questionnaires). Online questionnaires will be completed at baseline, directly post-treatment, and at 3, 6 and 12 months post-treatment. Polysomnography, pressure pain thresholds and actigraphy will be carried out at baseline, post-treatment and at 12 months follow-up.

Discussion

Findings may provide (1) a novel therapeutic approach for people with CSP and comorbid insomnia to improve pain, sleep, physical activity and function, and (2) new treatment guidelines for professionals.

Trial registration

Clinicaltrials.gov NCT03482856 (https://clinicaltrials.gov/ct2/show/NCT03482856).  相似文献   
89.
Understanding cellular uptake and intracellular processing of nonviral gene delivery systems is a key aspect in developing more efficient vectors. In this study, the impact of clathrin- and caveolae/lipid-raft-dependent endocytosis on cell entry and overall transfection efficiency of polyethylenimine (PEI) polyplexes was evaluated. Most remarkably, the internalization pathway mediating successful transfection depended on both cell type and polyplex type applied. Colocalization studies with transferrin and cholera toxin B revealed that at least two specific endocytosis pathways--the clathrin-dependent and the lipid-raft-dependent--mediated cellular uptake of PEI polyplexes. With the help of specific uptake inhibitors (chlorpromazine and filipin III), cell-line-dependent variations regarding the route of successful transfection were observed (HUH-7, COS-7, HeLa). In COS-7 cells, the clathrin-dependent pathway was the main contributor to the transfection process. In HUH-7 cells, gene transfer by linear PEI polyplexes succeeded mainly via the clathrin-dependent route, whereas transfection by branched PEI polyplexes was mediated by both pathways. In HeLa cells, both pathways were able to mediate successful gene delivery. However, the lipid-raft-dependent pathway was more relevant. The study also revealed that the concentration window between specific inhibitory function and nonspecific toxicity of the uptake inhibitors was very narrow.  相似文献   
90.
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