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41.
With simulation clinics, dental schools have improved their preclinical laboratories to provide a more realistic clinical teaching environment. However, there is very little data to support the assumption that these facilities actually improve student performance of technical skills. This study compared the scores of two fixed preparations for full cast crowns by third-year dental students. One of the preparations was made in the simulation clinic manikin, and the other was prepared on the bench top. Three prosthodontic faculty members scored the preparations in the areas of occlusal reduction, axial reduction, resistance and retention, and margination. The study also compared the performance of three classes of dental students: one class with no experience in the simulation clinic, one with one year of experience, and one with two years of experience. The amount of time since completing the fixed prosthodontics course among the students was also evaluated. This was done because the third-year students at the University of Iowa rotate through a series often-week clerkships rather than a comprehensive care model. (Therefore, not all students start clinical prosthodontics at the same time.) In addition, all student participants completed a questionnaire that addressed their perception of their clinical readiness prior to treating their first fixed prosthodontic patient. When we compared the classes of years 1, 2, and 3 by average preparation score, we found a significant difference among the scores for teeth prepared on the bench top (p = 0.0001) but not for the teeth prepared in the mannequin (p = 0.1176). For Year 1 (no simulation clinic experience), the amount of elapsed time following completion of the fixed prosthodontic course was not significant for the tooth prepared on the bench top or in the manikin (p = 0.57113 and 0.0661). For Year 2 (one year of simulation clinic experience), the elapsed time following completion of the fixed prosthodontic course was significant for the tooth prepared on the bench top (p = 0.0482), but it was not significant for the tooth prepared in the manikin (p = 0.2968). For Year 3 (two years of simulation clinic experience), the amount of elapsed time following completion of the fixed prosthodontic course was not significant for the tooth prepared on the bench top or in the manikin (p = 0.7275 and 0.6007). The questionnaire revealed that, in general, the majority of the students perceived their clinical readiness as more than adequate. These results are mixed in that students with more bench top experience scored better on the bench top, and students with more manikin experience scored equally in both environments.  相似文献   
42.
Cone beam computed tomography (CBCT) has been at the forefront of recent technological advances within the maxillofacial region. CBCT is useful in the accurate assessment and planning of patients undergoing orthognathic surgery. We propose that it also has a role in the post-operative evaluation of a subgroup of patients who have suffered complications at the time of surgery. We present two cases where unfavourable splits occurred during a bilateral sagittal split osteotomy (BSSO) of the mandible. Both cases were investigated post-operatively with CBCT with the aim of identifying the potential cause of the unfavourable split and to establish accurate localization of the condyle in the glenoid fossa following intra-operative attempts at proximal segment control. CBCT should be considered for evaluation of the mandible following an unfavourable split where it is deemed that plain radiographs would not provide adequate information.  相似文献   
43.
BACKGROUND: Recurrent gingival hyperplasia due to plasminogen deficiency is a rare condition due to fibrin deposition in the connective tissue. Only eight cases have previously been reported in the English literature, and all cases were diagnosed before the age of 35 years. This paper presents an older patient with recurrent gingival hyperplasia due to plasminogen deficiency (hypoplasminogenemia). METHODS: A 59-year-old woman presented with recurrent gingival swelling of 6 years' duration. Multiple biopsies performed at various time periods were histologically reported to be gingival hyperplasia with chronic inflammation. Routine hematoxylin and eosin (H & E) staining and direct immunofluorescence were performed. RESULTS: H & E-stained sections showed subepithelial, eosinophilic, amorphous, acellular deposits. Direct immunofluorescence showed positive staining for fibrin, immunoglobulin (Ig) G, IgA, and IgM. Functional plasminogen and plasminogen activator inhibitor-1 assays were done and found to be deficient. A diagnosis of gingival hyperplasia due to plasminogen deficiency (hypoplasminogenemia) was rendered. CONCLUSIONS: Recurrent gingival hyperplasia due to plasminogen deficiency (hypoplasminogenemia) is a newly recognized and rare condition. H & E staining, direct immunofluorescence, and assessment of functional plasminogen levels are essential to differentiate this condition from other conditions in which subepithelial, eosinophilic, amorphous materials are deposited.  相似文献   
44.
OBJECTIVE: To compare the safety and efficacy of a novel battery-operated interdental cleaning device (Oral-B Hummingbird) [ID], fitted with either a flossette or pick attachment, versus hand-held dental floss in the reduction of plaque and gingivitis when combined with manual tooth brushing over a 30-day period. METHODOLOGY: This randomized, examiner blind, parallel group study assessed three treatment groups: ID/flossette (ID/F), ID/pick (ID/P), and unwaxed manual dental floss. All groups used the same soft manual toothbrush and toothpaste. The 84 subjects were stratified to treatment groups based on initial whole mouth mean plaque scores, gingivitis scores, and gender. Subjects were instructed to brush twice daily and use their assigned interdental method once daily in the evening before brushing. Gingivitis, gingival bleeding, and plaque were evaluated at baseline and Day 30. RESULTS: A total of 78 subjects completed all aspects of the study and were included in the analyses. There was no significant difference between treatment groups in baseline plaque, gingivitis, and bleeding scores. After 30 days, statistically significant reductions from baseline gingivitis and bleeding scores were found for all groups (p < 0.0001), but there were no significant statistical differences among groups. Whole mouth and approximal plaque scores were significantly reduced from baseline in the manual floss and ID/F groups after 30 days of product use, with no significant difference between groups. Plaque reduction for both the manual floss and ID/F groups was significantly greater than the ID/P group. All interdental cleaning methods were safe as used in the study, with no evidence of oral hard or soft tissue trauma. CONCLUSION: The Oral-B Hummingbird was safe and effective in reducing approximal plaque and gingival inflammation, and provides a useful alternative device for interdental cleaning.  相似文献   
45.
The use of odds ratio (OR) in risk analysis is considered a useful means of cross-comparing risk factors by which a disease is influenced. This article outlines the interpretation of reported ORs with respect to periodontal disease, highlighting those factors that are most deserving of consideration. The claim that periodontal disease is implicated in some serious systemic diseases is investigated with respect to the evidence. Data retrieval was carried out, focusing primarily on ORs for factors shown to be positively correlated with the incidence of periodontal disease. Using the available data, a risk evaluation scoring system was proposed (the Cronin/Stassen BEDS CHASM scale). The results of the evaluation support the view that hygiene therapy, smoking cessation and control of the glycaemic state offer the largest and most easily achieved reduction in risk with respect to attachment loss. The literature on systemic diseases indicates that the mechanisms with which periodontitis may interact seem biologically plausible, compellingly so in the cases of coronary heart disease and diabetes mellitus. However, statistical evidence to confirm these suggested interactions is equivocal, with the data retrieved in some instances being less than decisive. Further investigation is recommended.  相似文献   
46.
The aim of orthognathic surgery is to produce a more aesthetic facial skeletal appearance, and improve jaw function. This prospective study, aimed to evaluate the impact of orthognathic surgery on quality of life for patients with dentofacial deformity, and whether it was clinically meaningful. 62 consecutive patients were recruited (27 male, 35 female) aged 18–38 years. Baseline data were collected using a validated health status measure (Orthognathic Quality of Life Questionnaire (OQLQ)) and a visual analogue scale (VAS). Postoperative questionnaires (OQLQ, VAS) and a Global Transition Scale (GTS) were completed at 6 months after completion of treatment and compared with pre-treatment scores. Following surgery, there was a significant (p < 0.05, paired t test) improvement in OQLQ scores for each domain. The proportion of patients reporting a moderate or large improvement was: facial appearance (93%), chewing function (64%), comfort (60%) and speech (32%). Clinical relevance of change scores was reported in terms of effect sizes, and the largest effect was on facial aesthetics. The clinical impact was moderate on social aspects of deformity and oral function and a small effect on awareness of facial deformity. This research reaffirms that orthognathic surgery has positive effects on quality of life.  相似文献   
47.
Dental implants for orthodontic anchorage   总被引:7,自引:0,他引:7  
The purpose of this article is to review and update current concepts involving the use of dental implants for orthodontic anchorage. Topics to be discussed include indications, implant requirements (eg, materials, size, designs of dental implants), surgery and healing time, biomechanics and forces, loading time, implant maintenance, posttreatment considerations, and disadvantages.  相似文献   
48.
Oral hygiene habits are strongly associated with general health behaviours; good oral self care should result in good dental health. Clinical dental hygiene services have limited long range probability of success if the patient is not diligent in the daily procedures of personal care to remove and control dental plaque. Therefore, it is important to help make the individual aware of their own ability to control and maintain good oral health after a dental prophylaxis through oral care instruction and the use of select antimicrobials to maintain the gingival health. This paper reviews the evidence outlining the relative roles of prophylaxis and correct oral self-care in maintaining gingival health.  相似文献   
49.
50.
This study compared the imaging performance of a photostimulable phosphor system with E speed film for dental radiography. The response of each imaging system was measured as a function of radiation exposure. Measurements were also made of imaging performance in terms of the limiting spatial resolution and low contrast detectability. Photostimulable phosphors had a wider dynamic range in comparison with film. The limiting spatial resolution of the photostimulable phosphor was approximately 6.5 lp/mm and independent of image magnification. For film, the limiting spatial resolution was in the range 11 to 20 lp/mm depending on image magnification. At the same radiation exposure, low contrast detectability of the photostimulable phosphor was superior to that of film. Major benefits of photostimulable phosphor systems include the elimination of chemical processing and an improved low contrast detectability performance.  相似文献   
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