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31.
The aim of the present study was to determine the percentage of dentists who use radiographic examination on the initial appointment, and establish the relation between the use of periodontal probe and graduation year. Dentists were interviewed in their private offices in three cities in Rio Grande do Sul. They were asked about the routine use of radiographic examination and, if applicable, what technique was applied and what clinical instrument was used at the first appointment. Opened and closed questions were included in the interview and for some of them more than one answer was possible. A significant number of dentists (62.9%) reported some kind of radiographic examination at the initial appointment. Among the radiographic techniques, the periapical was the most cited (74.3%), followed by the panoramic (36.2%) and bite-wing (32.9%) techniques. There was an association between the use of periodontal probe and the use of radiographic examination at the initial appointment. Dentists who used periodontal probe used radiographic examination more frequently (p=0.010). More recently graduated dentists (1991-2005) used radiographic examination more than the others (p=0.022). In conclusion, a large number of dentists reported the use of radiographic examination at the initial appointment. There was an association between the use of this examination technique and the use of the periodontal probe; recently graduated dentists used radiographic examinations more frequently than the others.  相似文献   
32.
Nervus intermedius neuralgia (NIN) is an uncommon disorder that affects a sensory branch of the facial nerve. This condition usually provokes a very intense and stabbing pain localized in the depth of the ear canal. Due to the close anatomical proximity, temporomandibular joint (TMJ) pathologies should be included in the differential diagnosis. The treatment of NIN has not been established, although it seems reasonable that the therapeutic approaches used in other more common craniofacial neuralgias, such as trigeminal neuralgia, should be effective. In this paper, the authors present a case report of a female patient diagnosed with NIN who was successfully managed with pharmacological treatment.  相似文献   
33.
Florid cemento-osseous dysplasia has been described as a condition that characteristically affects the jaws of middle-aged black women. It usually manifests as multiple radiopaque cementum-like masses distributed throughout the jaws. This condition has also been classified as gigantiform cementoma, chronic sclerosing osteomyelitis, sclerosing osteitis, multiple estenosis and sclerotic cemental masses. The authors present a case of an uncomplicated florid cemento-osseous dysplasia in a 48-year-old black woman. Multiple sclerotic masses with radiolucent border in the mandible were identified radiographically. Histopathologic findings revealed formation of calcified dense sclerotic masses similar to cementum. All clinical, radiographic, biochemical and histological features were suggestive of the diagnosis of florid cemento-osseous dysplasia.  相似文献   
34.
Ameloblastoma is a benign locally aggressive infiltrative odontogenic lesion. It is characterized by slow growth and painless swelling. The treatment for ameloblastoma varies from curettage to en bloc resection, and the reported recurrence rates after treatment are high; the safety margin of resection is important to avoid recurrence. Advances in technology brought about great benefits in dentistry; a new generation of computed tomography scanners and 3-dimensional images enhance the surgical planning and management of maxillofacial tumors. The development of new prototyping systems provides accurate 3D biomodels on which surgery can be simulated, especially in cases of ameloblastoma, in which the safety margin is important for treatment success. A case of mandibular follicular ameloblastoma is reported where a 3D biomodel was used before and during surgery.  相似文献   
35.

Purpose:

The aim of the present study was to evaluate the alterations of surface microhardness and wear caused by the sodium bicarbonate jet on bovine enamel and the further remineralizing effect of artificial saliva.

Methods:

Fifteen enamel samples (4,0mm × 4,0mm) were used, which constituted the groups: no treatment (MI); treatment with sodium bicarbonate jet (MII and DI); treatment with sodium bicarbonate jet and immersion in saliva for one hour (MIII and DII), 24 hours (MIV and DIII) and 7 days (MV and DIV). Microhardness tests were carried out using a microdurometer in groups M and wear tests by a rugosimeter in groups D. The data were assessed by the one criterion variance analysis and Tukey test.

Results:

The mean value of microhardness, in KHN, in groups MI, MII, MIII, MIV and MV were 359,80; 335,46; 369,20; 377,73 and 341,86, respectively, whereas the mean values in μm, of wear for group DI, DII, DIII and DIV were 0,564; 0,519; 0,441 and 0,428, respectively.

Conclusions:

The sodium bicarbonate jet caused a wear and a reduction in microhardness on the enamel surface; saliva promoted the recovery of initial condition surface microhardness and reduced the wear; the repairing effect of saliva on the surface microhardness alterations occurred within one hour of treatment, having no significant statistical difference from the effect obtained in 24 hours; the best saliva repairing effect on the wear occurred with treatment of 24 hours.  相似文献   
36.
The aim of this case-controlled study was to assess the effect of orthodontic treatment on the quality of life of Brazilian adolescents. Two hundred and seventy-nine 'cases' (106 males and 173 females) and 558 controls (246 males and 312 females) were randomly selected from 15- to 16-year-old adolescents attending all secondary schools in Bauru, S?o Paulo, Brazil. A case was defined as having at least one condition-specific impact (CSI) attributed to malocclusion during the previous 6 months, based on the Oral Impact on Daily Performances index. Conversely, a control was defined as having no CSI attributed to malocclusion during the same period. Adolescents were also clinically examined for orthodontic treatment need using the Index of Orthodontic Treatment Need (IOTN) and asked about previous orthodontic treatment. Binary logistic regression was used for statistical analysis. Females and adolescents with a definite normative orthodontic treatment need were more likely to report CSI than males and adolescents with no normative need [odds ratio (OR) = 1.48, 95 per cent confidence interval (CI) = 1.08-2.02 and OR = 2.02, 95 per cent CI = 2.09-4.47, respectively], whereas adolescents with a history of orthodontic treatment were less likely to report CSI than their counterparts (OR = 0.15, 95 per cent CI = 0.07-0.31). Furthermore, there was an interaction between a history of orthodontic treatment and the current level of normative need. Brazilian adolescents with a history of orthodontic treatment were less likely to have physical, psychological, and social impacts on their daily performances associated with malocclusion than those with no history of orthodontics. Gender was a confounding factor, whereas current level of normative orthodontic treatment need was an effect modifier. Prospective studies are needed to corroborate the present findings.  相似文献   
37.
The objective of this study was to compare the occlusal changes of Class II malocclusion treatment provided by two different types of appliances. Group 1 comprised 25 patients treated with the Fr?nkel appliance and group 2 comprised 30 patients treated with the eruption guidance appliance. Evaluations were performed on the initial and final study models of the patients using the peer assessment rating (PAR) index. The final mean PAR index, the mean PAR change, and the percent PAR reduction of each group were compared using the Student's t-test. Results demonstrated that there were no statistically significant differences between the final PAR index, the PAR changes, and the percent PAR reduction of the two groups. Therefore, it was concluded that the occlusal changes provided by the two appliances are similar, as evaluated by the PAR index.  相似文献   
38.
OBJECTIVES: To determine the effect of grinding on the bonding effectiveness of a self-etch and an etch-and-rinse adhesive to fluorosed enamel. METHODS: The teeth were classified using the Thylstrup and Fejerskov index (TFI). Fluorosed teeth (TFI=5) obtained from Isparta (Turkey) and control teeth (TFI=0) obtained from Leuven (Belgium) were used. Using a depth-marking diamond bur, 0.3mm of enamel was removed from mid-buccal and mid-palatal/lingual surfaces of the teeth, whereas the area adjacent to the ground area was left unprepared. A two-step self-etch (Clearfil Protect Bond, Kuraray) and a three-step etch-and-rinse adhesive (Optibond FL, Kerr) were used to bond the resin composite to the ground and unground enamel. Rectangular micro-specimens were prepared using the slow-speed diamond saw and tested in tensile to determine the micro-tensile bond strength (microTBS). RESULTS: The microTBS to unground fluorosed enamel was significantly lower than to ground fluorosed enamel for Clearfil Protect Bond (15.8+/-15.2 and 45.0+/-12.4MPa, p<0.0001) and for Optibond FL (35.5+/-21.4 and 50.5+/-12.3MPa, p<0.05), respectively. In control teeth, Clearfil Protect Bond bonded better to ground enamel (p<0.01), whereas OptiBond FL exhibited a similar bonding effectiveness to ground and unground enamel (p=0.0634). SIGNIFICANCE: Preparation of enamel improved the resin-enamel bond strength in fluorosed teeth. The bonding effectiveness to unground enamel was lower in fluorosed teeth than in control teeth for the self-etch adhesive tested.  相似文献   
39.
This article reports the case of a 19-year-old young man with Class III malocclusion and posterior crossbite with concerns about temporomandibular disorder (TMD), esthetics and functional problems. Surgical-orthodontic treatment was carried out by decompensation of the mandibular incisors and segmentation of the maxilla in 4 pieces, which allowed expansion and advancement. Remission of the signs and symptoms occurred after surgical-orthodontic intervention. The maxillary dental arch presented normal transverse dimension. Satisfactory static and functional occlusion and esthetic results were achieved and remained stable. Three years after the surgical-orthodontic treatment, no TMD sign or symptom was observed and the occlusal results had not changed. When vertical or horizontal movements of the maxilla in the presence of moderate maxillary constriction are necessary, segmental LeFort I osteotomy can be an important part of treatment planning.  相似文献   
40.
The aim of this study was to evaluate the cleaning efficacy of 2% chlorhexidine gluconate gel (CHX) compared to 2.5% sodium hypochlorite solution (NaOCl) associated or not with 17% EDTA used as irrigants during the biomechanical preparation. Fifty freshly extracted single-rooted human teeth with complete apex formation were randomly divided into five groups: G1 - sterile saline, G2 - 2.5% NaOCl, G3 - 2% CHX, G4 - 2.5% NaOCl + EDTA and G5 - 2% CHX + EDTA. The specimens of G1 were subdivided into two control groups. The teeth were decoronated and the coronal and middle root thirds were prepared with Gates-Glidden burs, and the apical third was reserved to manual instrumentation. All procedures were performed by a single operator. In all groups, 2 mL of irrigant was delivered between each file change. The teeth were sectioned and prepared for analyses under scanning electron microscopy (SEM). SEM micrographs were graded according to a score scale by two examiners. Data were analyzed statistically by Kruskal-Wallis and Dunn tests at 1% significance level. The best results were obtained in the groups in which the irrigant was used followed by the chelating agent. No statistically significant difference was observed among G4, G5 and the positive control group (p<0.01). The groups G2 and G3 were significantly different from the others, presenting the worst cleaning capacity. In conclusion, the use of the chelating agent is necessary to obtain clean canal walls, with open tubules and no heavy debris. The use of 2% chlorhexidine gluconate gel alone is not able to remove the smear layer.  相似文献   
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