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51.

Objectives

Enamel matrix derivative (EMD) has proven to enhance periodontal regeneration; however, its effect is mainly restricted to the soft periodontal tissues. Therefore, to stimulate not only the soft tissues, but also the hard tissues, in this study EMD is combined with an injectable calcium phosphate cement (CaP; bone graft material). The aim was to evaluate histologically the healing of a macroporous CaP in combination with EMD.

Materials and methods

Intrabony, three-wall periodontal defects (2?×?2?×?1.7 mm) were created mesial of the first upper molar in 15 rats (30 defects). Defects were randomly treated according to one of the three following strategies: EMD, calcium phosphate cement and EMD, or left empty. The animals were killed after 12 weeks, and retrieved samples were processed for histology and histomorphometry.

Results

Empty defects showed a reparative type of healing without periodontal ligament or bone regeneration. As measured with on a histological grading scale for periodontal regeneration, the experimental groups (EMD and CaP/EMD) scored equally, both threefold higher compared with empty defects. However, most bone formation was measured in the CaP/EMD group; addition of CAP to EMD significantly enhanced bone formation with 50 % compared with EMD alone.

Conclusions

Within the limits of this animal study, the adjunctive use of EMD in combination with an injectable cement, although it did not affect epithelial downgrowth, appeared to be a promising treatment modality for regeneration of bone and ligament tissues in the periodontium.

Clinical relevance

The adjunctive use of EMD in combination with an injectable cement appears to be a promising treatment modality for regeneration of the bone and ligament tissues in the periodontium.  相似文献   
52.

Background

Regularly, patients are not involved in development of evaluative tools. Investigators define outcomes according to their interests. These can be different with those of the patients. Therefore, it may be difficult for patients to choose between treatment options, because the outcomes’ measurements may not reflect their problems in daily life. Most ideally, patients are involved from the beginning in the development of an outcome measurement tool. In this study, a new concept was demonstrated in which a questionnaire was developed in collaboration with patients to evaluate the quality of surgical care of a frequently encountered entity (carpal tunnel syndrome) that is meaningful for and understandable by patients.

Methods

Through a patient participatory research in an academic hospital, 50 consecutive patients who recently underwent surgical decompression of carpal tunnel syndrome were asked to optimize a questionnaire. An existing questionnaire was sent to the patients with the request to grade the relevance of each question. They were also offered the possibility to add questions from their point of view.

Results

All questions were found relevant. Finally, the questionnaire was modified by adding one question proposed by the patients. They wanted to include a question that would evaluate the effect of the treatment. Therefore, a question was introduced to evaluate the effect of the surgery on the symptoms and signs with a six-item Likert scale varying from severely worsened to free of signs and symptoms. Finally, the EQ-5D-5 L was added as a measure of quality of life.

Conclusions

The participation of patients is essential but until now not usual when a tool for evaluating the success of a treatment is developed. Information that is meaningful for patients but not obligate for researchers can easily be missed in the classical development of outcome measurement tools. This information will be crucial when future patients try to understand the findings of research in order to make an appropriate decision between eventual treatment options.  相似文献   
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55.
Patient matched instrumentation is a new operative tool in the field of total knee arthroplasty. Custom made cutting blocks are designed to perform distal femoral and tibial bone cuts according to a pre-operative planning. This study evaluates the Visionaire system of Smith & Nephew. Thirty-one patients, operated with the Visionaire technique, were compared to an equal control group for different clinical and radiographic outcome parameters. Between both groups, no statistical significant difference could be found in post-operative pain, satisfaction, functional outcome, hospital stay, blood loss, radiographic alignment and precision of bone cuts. Only tibial plateau backslope can be created with more precision in the Visionaire group. But there was a statistical significant difference for residual flexion deformity after a mean follow-up time of 200 days.  相似文献   
56.
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In a series of 13 patients with cerebrovascular occlusive disease regional cerebral blood flow (rCBF) measurements (two-dimensional intravenous 133Xe clearance method) and quantitative EEG analysis (sensorimotor rhythms) as well as electronic measurement of handforce were performed before and during intravenous infusion of 1 μg kg/min of one of the lipophilic dihydropyridine calcium channel blocker nimodipine (Nimotop®). The aim of the study was to test the hypothesis of the existence of hypoperfusion (ischaemic penumbra) in the surroundings of chronic cerebral infarcts. All 3 parameters improved in one patient. Sensorimotor rhythms increased in 5 patients, rCBF in 3. EEG and rCBF improved in 2 patients. In 3 instances, a redistribution of rCBF in favour of the peri-infarct zone was noted (significant increase of rCBF from 35 ± 2 sem to 53 ± 4 ml/100 g/min (p > 0.01), whereas rCBF fell from 61 ± 5 to 46 ±2 ml/100 g/min on a collimator remote from the infarct but in the infarcted hemisphere. The parallel improvement of rCBF and EEG in brain regions surrounding chronic infarcts in 3 patients was interpreted as functional improvement as a consequence of nimodipine-induced normalization of peri-infarct hypoperfusion, i.e. reversal of flow-dependent neuronal silence and/or dysfunction.  相似文献   
58.
Protein phosphorylation and dephosphorylation events play a key role in memory formation and various protein kinases and phosphatases have been firmly associated with memory performance. Here, we determined expression changes of protein kinases and phosphatases following retrieval of spatial memory in CD1 mice in a Morris Water Maze task, using antibody microarrays and confirmatory Western blot. Comparing changes following single and consecutive retrieval, we identified stably and differentially expressed kinases, some of which have never been implicated before in memory functions. On the basis of these findings we define a small signaling network associated with spatial memory retrieval. Moreover, we describe differential regulation and correlation of expression levels with behavioral performance of polo‐like kinase 1. Together with its recently observed genetic association to autism‐spectrum disorders our data suggest a role of this kinase in balancing preservation and flexibility of learned behavior. © 2013 Wiley Periodicals, Inc.  相似文献   
59.
To determine the effectiveness of training programs that focus on lower-limb strengthening, cardiorespiratory fitness, or gait-oriented tasks in improving gait, gait-related activities, and health-related quality of life after stroke. Randomized controlled trials (RCTs) were searched for in the databases of Pubmed, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, DARE, Physiotherapy Evidence Database (PEDro), EMBASE, Database of the Dutch Institute of Allied Health Care, and CINAHL. Databases were systematically searched by two independent researchers. The following inclusion criteria were applied: (1) participants were people with stroke, older than 18 yrs; (2) one of the outcomes focused on gait-related activities; (3) the studies evaluated the effectiveness of therapy programs focusing on lower-limb strengthening, cardiorespiratory fitness, or gait-oriented training; and (4) the study was published in English, German, or Dutch. Studies were collected up to November 2005, and their methodological quality was assessed using the PEDro scale. Studies were pooled and summarized effect sizes were calculated. Best-evidence synthesis was applied if pooling was impossible. Twenty-one RCTs were included, of which five focused on lower-limb strengthening, two on cardiorespiratory fitness training (e.g., cycling exercises), and 14 on gait-oriented training. Median PEDro score was 7. Meta-analysis showed a significant medium effect of gait-oriented training interventions on both gait speed and walking distance, whereas a small, nonsignificant effect size was found on balance. Cardiorespiratory fitness programs had a nonsignificant medium effect size on gait speed. No significant effects were found for programs targeting lower-limb strengthening. In the best-evidence synthesis, strong evidence was found to support cardiorespiratory training for stair-climbing performance. Although functional mobility was positively affected, no evidence was found that activities of daily living, instrumental activities of daily living, or health-related quality of life were significantly affected by gait-oriented training. This review shows that gait-oriented training is effective in improving walking competency after stroke.  相似文献   
60.
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