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11.
Angela Pierce 《Australian endodontic journal : the journal of the Australian Society of Endodontology Inc》1998,24(2):60-65
Diagnosis of pulpal disease can be difficult due to the lack of diagnostic signs and symptoms available to the practitioner. An understanding of the possible underlying pathological processes, combined with an exact assessment of the pain history, and appropriate clinical tests, should aid the practitioner in determining the nature of pulpal inflammation, and differentiating it from dentine sensitivity and cracked teeth. The responses of the pulp to traumatic injury to the periodontal membrane (PDM) require special consideration, particularly with respect to the assessment of pulp vitality, and the determination of cases requiring pulp extirpation in order to avoid inflammatory root resorption. Although the pulp is relatively isolated from the rest of the dentoalveolar complex by a dentine/cementum barrier, it is important to remember that it can communicate with the PDM through apical and lateral foramina, and areas of damaged cementum. Hence, it is a priority to both preserve the integrity of the cemental layer in cases of traumatic injury and periodontal disease, and to prevent the inflammation and resorption associated with periapical lesions by accurate diagnosis of irreversible pulpitis and pulp necrosis, followed by appropriate endodontic debridement procedures. 相似文献
12.
Limongi O Klymus AO Baratto Filho F Vanni JR Travassos R 《Journal of applied oral science : revista FOB》2004,12(3):195-199
The present study conducted an in vitro evaluation of the presence of apical deviation on the root canal preparation of the mesiobuccal roots of human maxillary molars employing automated handpieces with continuous motion, the Pow R system (Moyco Union Broach), and alternate motion, the M4 system (Kerr). Analysis of the presence of apical deviation was carried out by means of radiographs obtained on a radiographic desk fabricated for the study. The results demonstrated the lack of statistically significant differences between the two systems as to the evaluation of the presence of apical deviation. There was no correlation between the degree of curvature of the roots and the degree of apical deviation for the continuous motion system. However, there was a statistic difference for the alternate motion system, with a direct correlation of moderate degree. 相似文献
13.
Lars Hammarström Angela Pierce Leif Blomlöf Barry Feiglin Sven Lindskog 《Dental traumatology》1986,2(1):1-8
Abstract The major causes of post-replantation tooth loss are inflammatory root resorption and root resorption associated with ankylosis. Recent studies have concentrated on delineating the cellular interactions in the pulp and periodontium in order to more fully understand the various factors affecting the prognoses of such teeth. The aim of this report is to discuss the nature of the pathology responsible for tooth loss following avulsion and to review recent replantation and attachment studies. 相似文献
14.
The goal of this study was to evaluate skeletal, dental and chronological development in an HIV-positive group of children, as compared with a control group, during a four-year period. Panoramic radiographs and hand and wrist radiographs of 60 children were taken. The children, of both sexes, aged 5 years and 2 months to 15 years and 5 months, were selected as follows: 30 HIV-positive volunteers who had acquired the disease vertically, and 30 volunteers who did not present the HIV infection or any other systemic disease. All radiographs were technically standardized and analyzed according to criteria established by Nolla (dental age), Greulich and Pyle (bone age), and Ekl?f and Ringertz (bone age). The results were submitted to Student's t-test at a 5% level of significance. Based on the comparison between the chronological age and the dental or the skeletal age, significant differences were observed between HIV-positive and HIV-negative children, both in 1999 and in 2003 (p < or = 0.05). Considering the results obtained with the methodology used, it was concluded that HIV-positive children of both sexes presented delayed bone development despite the administration of antiretroviral drugs, and that HIV-positive female children presented younger dental ages compared with their chronological ages in 1999 and in 2003; and HIV-positive males, in 1999. 相似文献
15.
Amelogenin, a major structural protein in mineralizing enamel, is also expressed in soft tissues: brain and cells of the hematopoietic system 总被引:1,自引:0,他引:1
16.
Rosa PC Mancini MN Camargo SE Garrido AD Camargo CH Rode Sde M 《Brazilian dental journal》2010,21(4):301-304
This study evaluated the dimensional alterations and the solubility of two experimental endodontic sealers based on Copaifera multijuga oil-resin (Biosealer) and castor oil bean cement (Poliquil), maintained in different storage solutions. Twenty specimens (3 mm diameter and 2 mm height) of each sealer were assigned to 2 groups (n=10) according to the storage solution: simulated tissue fluid (STF) or distilled water (DW). The specimens were stored in these solutions during 90 days, being removed every 30 days for weighting. The solutions were renewed every 15 days. The results were subjected to statistical analysis by Dunn's and Mann-Whitney tests (a=0.05). The solubility of Poliquil was higher in STF (38.4 ± 36.0) than in DW (28.4 ± 15.0), while Biosealer showed higher solubility in DW (34.61 ± 6.0) than in STF (18.59 ± 8.0). The storage solution influenced the behavior of sealers in relation to the weight variation (p=0.0001). Poliquil presented higher variation of weight independent of the solution (p=0.239). Biosealer also presented higher variation of weight regardless of the solution (p=0.0001). The solubility of Biosealer was different from that of Poliquil, but both sealers showed low solubility in STF. Under the tested conditions, neither of the materials were according to the ADA'S specification. 相似文献
17.
This experiment investigated the ability of tooth-colored mineral trioxide aggregate (MTA) to maintain an apical seal in the presence of bacteria when contaminated with blood, saline or saliva. Ninety extracted human teeth with single canals were randomly placed into six groups of 15. Canals were prepared to size 50. The apical 3 mm of each root was removed and 3 mm root-end preparations were made with a #329 bur. Root-end preparations in groups 1 through 3 were filled with MTA after contamination with blood, saline, or saliva, respectively. In group 4, uncontaminated root-end preparations were filled with MTA. Groups 5 and 6 served as negative and positive controls. A tube/tooth assembly was utilized to suspend each root end in Trypticase Soy Broth (TSB). The access chambers were filled with Staphylococcus epidermidis. Positive growth over thirty days was demonstrated by turbidity of the TSB. Vitek analysis was used to confirm the presence of S. epidermidis in the positive samples. Data evaluation consisted of a chi(2) analysis (p < 0.05). Although all experimental groups demonstrated leakage, tooth-colored MTA contaminated with saliva (group 3) leaked significantly more than the uncontaminated tooth-colored MTA (group 4) (p = 0.028). 相似文献
18.
Association of endodontic infection with detection of an initial lesion to the cardiovascular system
Cotti E Dessì C Piras A Flore G Deidda M Madeddu C Zedda A Longu G Mercuro G 《Journal of endodontics》2011,37(12):1624-1629
Introduction
Dental infections might predispose toward the onset of cardiovascular disease (CVD). To date, only a few studies, yielding inconclusive findings, have investigated the potential correlation between apical periodontitis (AP) and CVD. The aim of this study (as the first part of a prospective study) was to evaluate, in the absence of CV risk factors, whether subjects with AP were more exposed to the pathogenetic indices of an atherosclerotic lesion.Methods
Forty men between the ages of 20 and 40 years who were free from periodontal disease, CVD, and traditional CV risk factors were enrolled in the study; 20 subjects had AP, and 20 acted as controls. All subjects underwent dental examination and complete cardiac assessment: physical examination, electrocardiogram, conventional and tissue Doppler echocardiography, and measurement of endothelial flow reserve (EFR). The following laboratory parameters were tested: interleukins -1, -2, and -6 (IL-1, IL-2, IL-6), tumor necrosis factor alpha, and asymmetrical dimethylarginine (ADMA). Data were analyzed by using the 2-tailed Student's t test, Pearson t test (or Spearman t test for nonparametric variables), and multivariate linear regression analysis.Results
Echocardiography revealed no abnormalities in any of the subjects studied. ADMA levels were inversely correlated with EFR (P < .05) and directly correlated with IL-2 (P < .001). Patients with AP presented with significantly greater blood concentrations of IL-1 (P < .05), IL-2 (P < .01), IL-6 (P < .05), and ADMA (P < .05) and a significant reduction of EFR (P < .05).Conclusions
Increased ADMA levels and their relationship with poor EFR and increased IL-2 might suggest the existence of an early endothelial dysfunction in young adults with AP. 相似文献19.
BACKGROUND: Myeloid sarcoma is an extramedullary malignancy of myeloblasts. An unusual case of myeloid sarcoma presenting in the gingiva and affected by drug-induced gingival enlargement is presented. METHODS: A 63-year-old male taking amlodipine for his hypertension presented with a 3-week gingival enlargement. Although the obvious clinical impression was that of drug-induced gingival enlargement, an incisional biopsy was performed to corroborate chemical enlargement while ruling out diseases such as lymphoma and leukemia. RESULTS: Microscopic examination of the thickened gingiva revealed surface stratified squamous epithelium having needle-like rete pegs characteristic of drug-induced gingival enlargement. Beneath the surface epithelium, the fibrous tissue was virtually replaced by a dense infiltrate of malignant cells. Immunohistochemical studies were performed with CD117 and myeloperoxidase identifying the malignant cell population as myeloblasts, leading to a diagnosis of myeloid sarcoma. CONCLUSION: Myeloid sarcoma and hematopoietic malignancies must be included in a differential diagnosis of gingival enlargement until the definitive diagnosis is reached by histologic/laboratory examination. 相似文献
20.
Scaramucci T Hara AT Zero DT Ferreira SS Aoki IV Sobral MA 《Brazilian dental journal》2011,22(6):473-478
The aim of this study was to create a synthetic juice (SJ) to be used as a surrogate for natural orange juices in erosion studies, verifying its erosive potential. The SJ was formulated based on the chemical composition of orange juices from different locations. Forty enamel and 40 root dentin specimens were randomly assigned into 4 experimental groups (n = 10): SJ; 1% Citric Acid (CA); Minute Maid Original? (MM) and Florida Natural Original? (FN). The specimens were immersed in their respective solutions for 5 min, 6x/day for 5 days, in an erosion-remineralization cycling model. Enamel specimens were analyzed by surface Knoop microhardness and optical profilometry and dentin specimens only by optical profilometry. Outcomes were analyzed statistically by ANOVA followed by Tukey's test considering a significance level of 5%. For enamel, the surface loss and microhardness changes found for MM and SJ groups were similar (p>0.05) and significantly lower (p<0.01) than those found in the CA group. For dentin, CA promoted significantly greater (p<0.01) surface loss compared with all the other groups. No significant difference (p>0.05) was observed in dentin surface loss between MM and SJ. In conclusion, CA was the most erosive solution, and SJ had a similar erosive potential to that of MM natural orange juice. 相似文献