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21.
OBJECTIVE: Patients with a cleft lip or palate often present alterations in the labial aspect of the ridge, resulting in a shallow vestibule. This study compares the results of two different surgical procedures on deepening of the labial sulcus. INTERVENTIONS: Ten patients with a cleft lip and palate were separated into two groups and underwent different vestibuloplasty procedures. An experimental group used a removable retention splint. Preoperative and 4-month postoperative sulcus heights were measured and analyzed statistically. RESULTS: No statistically significant differences could be detected between groups. CONCLUSION: The results indicated that to reach consistent results, a larger number of patients must be submitted to this evaluation.  相似文献   
22.
This cross-sectional study investigated the distribution of plaque and gingivitis and its association with demographic, socioeconomic, and orthodontic variables (spacing in anterior teeth, anterior open bite, and crossbite), and visible plaque level (low, medium, high) in Brazilian preschoolers. The sample comprised 490 3- to 5-year-old children from nursery schools in Canoas, a city in southern Brazil. One single, trained observer examined children's oral cavities and determined visible plaque index (VPI) and gingival bleeding index (GBI). Results showed that 99% of the children had visible plaque and 77% had gingivitis (GBI>0). A positive (r(s)=0.32) and significant correlation was found between VPI and GBI. VPI and GBI were significantly higher in posterior teeth and buccal and lingual surfaces. VPI was significantly higher in boys, children of low-income families, and without spacing in maxillary anterior teeth. Gingivitis was associated with absence of spacing in maxillary anterior teeth and plaque level. The most prevalent areas of plaque and gingivitis identified in this study should be taken in consideration during oral hygiene instructions, which should be given to children and mothers-particularly those with a low socioeconomic status--to motivate self-care and prevent gingivitis.  相似文献   
23.
This study evaluated the predominant microbiota of infected necrotic pulps and the effects of calcium hydroxide therapy on these microorganisms by the checkerboard DNA-DNA hybridization technique. Conventional endodontic therapy associated with calcium hydroxide as intracanal dressing was performed in 12 single-rooted teeth with pulp necrosis and periradicular bone lesion. Samples were collected from the canal at baseline and 14 days after therapy, and the presence of 44 bacterial species was determined by the checkerboard method. Significant differences in the microbiota from baseline to post-therapy were sought by the paired-samples t test. The most prevalent species included F. nucleatum ss. vincentii, C. sputigena, C. ochracea, S. constellatus, V. parvula, P. gingivalis, P. melaninogenica, and S. sanguis. Most of the microorganisms were reduced after treatment, particularly A. gerencseriae, A. israelii, A. naeslundii, C. gingivalis, C. ochracea, P. gingivalis, S. noxia, S. sanguis, and S. oralis (p < 0.05). Conversely, A. actinomycetemcomitans, C. sputigena, and E. corrodens increased in numbers after therapy. These results indicate that conventional endodontic therapy with calcium hydroxide results in the reduction of pathogenic species associated with pulp necrosis. However, its use is limited, because it did not eliminate the whole spectrum of microorganisms.  相似文献   
24.
The main purpose of this study was to evaluate the preliminary results of a school-based oral health educational strategy adopted in public primary schools from the city of Maringa, State of Parana, Brazil. The study sample was composed by 556 children and adolescents aged 6 to 17 years old, 124 schoolteachers and a group of 55 mothers. The educational approach was implemented for 18 months and consisted of reinforcements of interventions addressed to students and schoolteachers at school level and few activities targeted at the mothers, performed by means of home visits. Baseline and follow-up interviews focused on oral health care were undertaken for the entire study population. As a stimulus for the students to achieve proper oral hygiene habits, the simplified oral hygiene index was assessed at three different moments. A statistically significant improvement in their oral hygiene index (p<0.001) was recorded. The results achieved suggest an encouraging tendency towards the improvement in the levels of oral health care among the school-age youths studied. They also point out the need of intensifying the preparation of schoolteachers in oral health topics, as well the instructions to the mothers for their oral health care. Moreover, they highlight the importance of the continuous implementation of school-based programs to promote the oral health.  相似文献   
25.
OBJECTIVES: The purpose of this study was to assess the sensory function of trigeminal nerve A-beta fibers in suspected soft tissue oral malignancies. STUDY DESIGN: Twenty-three patients referred for the evaluation of an oral lesion suspected of malignancy were included in the study. All lesions were classified as in, near, or out of the nerve territory containing the lesion. Within these subgroups we assessed the sensitivity of A-beta primary afferents to weak electrical currents applied bilaterally to regions innervated by 3 peripheral branches of the trigeminal nerve. The ratio of electrical detection thresholds from the affected and the unaffected side was calculated. Electrical detection threshold ratios were contrasted with the results of physical examination, radiographic imaging, and biopsy. RESULTS: For dermatomes containing the lesions, ratios were lower than 0.8 in 12 patients. Biopsy showed that the lesions in 10 of these 12 patients were malignant. No malignancy was found in the remaining 11 patients. CONCLUSIONS: A-beta primary afferent hypersensitivity is observed to occur in nerves exposed to soft tissue oral malignancy.  相似文献   
26.
27.
During the cementation of metallic restorations, the polymerization of dual-curing resin cements depends exclusively on chemical activation. This study evaluated the influence of chemical activation compared with dual-curing (chemical and light activation), on the hardness of four dual-curing resin cements. In a darkened environment, equal weight proportions of base and catalyst pastes of the cements Scotchbond Resin Cement, Variolink II, Enforce and Panavia F were mixed and inserted into moulds with cavities of 4 mm in diameter and 2 mm in height. Subsequently, the cements were: 1) not exposed to light (chemical activation = self-cured groups) or 2) photoactivated (dual-curing = dual-cured groups). The Vickers hardness number was measured at 1 hour, 24 hours and 7 days after the start time of cements' spatulation. For all the cements, the hardness values of self-cured groups were lower than those of the respective dual-cured groups at 1 hour and 24 hours. At 7 days, this behavior continued for Variolink II and Panavia F, whilst for Scotchbond Resin Cement and Enforce there was no statistical difference between the two activation modes. All cements showed a significant increase in their hardness values from 1 hour to 7 days for both activation modes. Of the self-cured groups, Scotchbond Resin Cement and Variolink II presented the highest and the lowest hardness values, respectively, for all three times tested. Within the limitations of this study, up to the time of 24 h, chemical activation alone was unable to promote similar hardness as to that obtained with dual-curing.  相似文献   
28.

Objective:

To evaluate the role of socioeconomic variables and self-perceived oral health in the polarization of caries among adolescents in Santa Bárbara D''Oeste, Brazil.

Material and Methods:

Cross-sectional study. Sampling was randomized and sample size was defined according to WHO criteria. Two hundred and seventy seven adolescents (15 to 18 year-old) were examined by five trained examiners that assessed DMFT index according to WHO criteria. Self-perceived oral health, access to dental services and socio-demographic variables were self-reported. Student''s t tests, chi-square tests, and multivariate logistic regression (with significant caries index (SiC) as the outcome), were performed.

Results:

Mean DMFT was 5.48 (±4.22) and the proportion of "caries free" subjects was 15.5%. Mean DMFT (9.71±2.85) and mean D (1.67±2.18) of SiC positive subjects were significantly higher than mean DMFT (2.88±2.17) and mean D (0.45±0.87) of SiC negative subjects (p<0.0001). Mean D of white (0.76±1.51) was significantly smaller than mean D of non-white subjects (1.32±2.01). The only variable independently associated with the "SiC positive" outcome was "report of toothache within six months prior to the study" [OR=1.83 (95%CI 1.08 to 3.12)], p<0.001.

Conclusion:

SiC was associated with "report of toothache" but not with sociodemographic variables in the studied population.  相似文献   
29.
AIM: To evaluate the incidence of disease recurrence following a full-mouth pocket/root debridement approach with ultrasonic instrumentation versus that following a traditional approach of quadrant-wise scaling and root planing (Q-SRP) performed with hand instrumentation. METHODS: Thirty-seven patients were re-examined 1 year after the completion of a 6-month clinical trial comparing two different treatment protocols: a 1-h session of full-mouth ultrasonic debridement (UD--19 patients) or four sessions of Q-SRP with hand instruments (Q-SRP--18 patients). At 3 months, re-instrumentation was performed of pockets showing a remaining probing pocket depth (PPD) of > or =5 mm using the same type of instruments as used during the initial treatment phase. The clinical examinations comprised assessments of plaque, bleeding on probing (BoP) and PPD. The primary outcome variable was the incidence of recurrent diseased sites (i.e., sites showing PPD > or =5 mm and BoP+) between the post-treatment and 1-year follow-up examinations. All sites that were healed (PPD < or =4 mm and BoP(-)) at the post-treatment examination were included in the study sample, with a mean number of sites per patient of 23.5. RESULTS: In the UD group, 29 (7%) out of 430 initially healed sites showed disease recurrence at the 1-year follow-up examination compared with 47 (11%) of 440 sites in the Q-SRP group (p>0.05). Twelve patients (63%) in the UD group presented recurrent diseased pockets, compared with 14 patients (78%) in the Q-SRP group. Two or more recurrent, diseased pockets were observed in nine patients in the UD group versus 11 in the Q-SRP group. All but one of the smokers belonged to the group of patients presenting recurrences. A tendency towards a higher mean plaque score was observed for the patients with recurrent sites. CONCLUSION: The study revealed no significant difference in the incidence of recurrence of diseased periodontal pockets between the full-mouth UD approach and the traditional approach of Q-SRP.  相似文献   
30.
Abstract – This article reports a longitudinal follow‐up of a 15‐month‐old child with dental trauma resulting from an attack by a dog. The injury consisted of laceration of the facial tissues and loss of the upper central deciduous incisors, in addition to loss of bone tissue in the same area. A malformation of the crown of the right central permanent incisor and complete change of the shape of the left central permanent incisor were observed. The etiological factors of childhood injuries as well as the importance of dental emergency care are discussed and the 14‐year clinical and radiographic follow up of the case is presented.  相似文献   
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