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991.
Harriet Mpairwe Juliet Ndibazza Emily L. Webb Margaret Nampijja Lawrence Muhangi Barbara Apule Swaib Lule Hellen Akurut Dennison Kizito Mohammed Kakande Frances M. Jones Colin M. Fitzsimmons Moses Muwanga Laura C. Rodrigues David W. Dunne Alison M. Elliott 《Pediatric allergy and immunology》2014,25(5):481-488
992.
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995.
Erick Miranda Souza Amanda Martins Calixto Camila Nara e Lima Fernanda Geraldo Pappen Gustavo De-Deus 《Journal of endodontics》2014
Introduction
Stabilizing sodium hypochlorite (NaOCl) at an alkaline pH is proposed to increase solution stability and tissue dissolution ability; however, a reduction on the flexural strength of dentin discs has been found to be a side effect. This study sought to determine whether a stabilized alkaline NaOCl reduces the fracture resistance of root canal–treated bovine teeth after root canal preparation compared with a neutral solution counterpart.Methods
The 4 anterior incisors were removed from 20 mandibular bovine jaws, and each 1 was randomly assigned to 1 of 4 groups (20 teeth each). Teeth were prepared with a sequence of 6 K-type files. The following experimental groups received a different irrigation regimen: G1: distilled water (negative control), G2: 5% NaOCl at a pH of 7.2, and G3: 5% NaOCl at a pH of 12.8; in the positive control group (G4), teeth remained untreated. The time of contact and volume of solution were carefully standardized. After bone and periodontal ligament simulation, teeth were subjected to a fracture resistance test.Results
A significant difference was observed among the 4 groups tested (analysis of variance, P < .05). The 5% NaOCl groups (G2 and G3) presented significantly lower resistance to fracture than the control (G1 and G4) (Tukey test, P < .05). Both NaOCl solutions similarly reduced the fracture resistance at approximately 30% (Tukey test, P > .05). No differences were observed between positive and negative control groups (Tukey test, P > .05).Conclusions
Stabilized alkaline and neutral NaOCl solutions similarly reduced the fracture resistance of root canal–treated bovine teeth by about 30%. 相似文献996.
Artur Aburad de Carvalhosa Cyntia Rodrigues de Araújo Estrela Álvaro Henrique Borges Orlando Aguirre Guedes Carlos Estrela 《Journal of endodontics》2014
Introduction
Radiographic images may lead to misinterpretations of lesions of endodontic and nonendodontic origin. This report describes a case of a 10-year follow-up of a calcifying odontogenic cyst (COC) in the periapical region of a vital maxillary central incisor in a 9-year-old boy.Methods
The patient revealed a history of a swelling in the periapical area of tooth #9. The patient denied any dental trauma or history of pain. Clinical examination revealed no mobility, but there was discrete discomfort when horizontal pressure was applied. Pulp vitality was present in all maxillary anterior teeth. Radiographs revealed an oval radiolucent lesion in the periapical region of maxillary central incisor. The therapeutic option was enucleation of the periapical lesion and histologic examination of the specimen. Microscopic findings suggested the diagnosis of a COC.Results
At a follow-up visit 10 years after surgery, panoramic and periapical radiographs showed new bone formation; the patient did not have any pain, and pulp vitality was maintained in all teeth in this area.Conclusions
A COC should be part of the differential diagnosis of other jaw lesions, such as apical periodontitis. The definitive diagnosis of a COC can only be made after microscopic evaluation of the specimen. The follow-up is a helpful reference because it confirms the survival of pulp tissue and no recurrence of the COC. 相似文献997.
Matheus Melo Pithon Iane Souza Nery Silva Indira Oliveira Almeida Marine Soares Nery Michele Luz de Souza George Barbosa Alex Ferreira dos Santos Raildo da Silva Coqueiro 《The Angle orthodontist》2014,84(2):231
Objective:To determine whether photos or silhouettes are adequate methods for evaluating the esthetic profiles of black subjects and whether black and white evaluators have different preferences for esthetic profiles.Materials and Methods:One photographic record of the profile of a black female patient with accentuated dental bimaxillary dentoalveolar protrusion was randomly selected. The image of the patient''s profile was altered to produce a series of seven photos and seven silhouettes (a total of 14 images) with different lip positions but uniform distances in relation to the esthetic plane created by Ricketts (line E). Fifty black and 50 white lay evaluators were invited to enumerate the photos and silhouettes, produced according to the lip position, in the order in which they considered most esthetically pleasing.Results:The number of preferences found to be within the esthetic norm was slightly higher among the photographs than among the silhouettes; the esthetic profile with a deviation of −2 mm from line E was elected as the most attractive, and the esthetic pattern with a deviation of +6 mm from the normal line E was considered the least attractive. There were no statistically significant differences between the preferences related to the variables race, sex, and educational background.Conclusions:The esthetic attractiveness of the facial profiles of black subjects in photos and silhouettes was evaluated in a similar manner among black and white evaluators. Among both black and white evaluators, the greatest preference was for the slightly concave profile, which was within the limit considered standard. 相似文献
998.
Mariana Marquezan Inay Lima Ricardo Tadeu Lopes Eduardo Franzotti Sant'Anna Margareth Maria Gomes de Souza 《The Angle orthodontist》2014,84(3):500
Objective: To compare the primary stability of miniscrews inserted into bone blocks of different bone mineral densities (BMDs) with and without cortical bone, and investigate whether some trabecular properties could influence primary stability.Materials and Methods:Fifty-two bone blocks were extracted from fresh bovine pelvic bone. Four groups were created based on bone type (iliac or pubic region) and presence or absence of cortical bone. Specimens were micro-computed tomography imaged to evaluate trabecular thickness, trabecular number, trabecular separation, bone volume density (BV/TV), BMD, and cortical thickness. Miniscrews 1.4 mm in diameter and 6 mm long were inserted into the bone blocks, and primary stability was evaluated by insertion torque (IT), mini-implant mobility (PTV), and pull-out strength (PS).Results:Intergroup comparison showed lower levels of primary stability when the BMD of trabecular bone was lower and in the absence of cortical bone (P ≤ .05). The Pearson correlation test showed correlation between trabecular number, trabecular thickness, BV/TV, trabecular BMD, total BMD, and IT, PTV, and PS. There was correlation between cortical thickness and IT and PS (P ≤ .05).Conclusion:Cancellous bone plays an important role in primary stability of mini-implants in the presence or absence of cortical bone. 相似文献
999.
Flavia Sirotheau Corrêa Pontes PhD Felipe Paiva Fonseca Adriana Souza de JesusLeila Marques Araújo MSc Liliane Silva do Nascimento Hélder Antônio Rebelo Pontes 《Journal of endodontics》2014
Introduction
This study aimed to analyze cases referred from a reference service in oral pathology that were initially misdiagnosed as periapical lesions of endodontic origin and to perform a review of the literature regarding lesions located in the apical area of teeth with a nonendodontic source.Methods
A survey was made of clinical cases derived from the service of oral pathology from 2002 to 2012. The pertinent literature was also reviewed using ScienceDirect and PubMed databases. The lesions were grouped into benign lesions mimicking endodontic periapical lesions (BLMEPLs), malignant lesions mimicking endodontic periapical lesions (MLMEPLs), and Stafne bone cavities. The clinical presentations were divided into lesions with swelling without pain, lesions with swelling and pain, and lesions without swelling but presenting with pain.Results
The results showed that 66% (37/56) of cases represented benign lesions, 29% (16/56) malignant lesions, and 5% (3/56) Stafne bone cavities. The most commonly reported BLMEPLs were ameloblastomas (21%) followed by nasopalatine duct cysts (13.5%). The most frequently cited MLMEPLs were metastatic injuries (31.5%) followed by carcinomas (25%). The main clinical presentation of BLMEPLs was pain, whereas that of MLMEPLs was swelling associated with pain; Stafne bone cavities displayed particular clinical findings.Conclusions
Clinical and radiologic aspects as well as the analysis of the patients' medical history, pulp vitality tests, and aspiration are essential tools for developing a correct diagnosis of periapical lesions of endodontic origin. However, if the instruments mentioned earlier indicate a lesion of nonendodontic origin, a biopsy and subsequent histopathological analysis are mandatory. 相似文献1000.
Igor Vieira BracksLuciana Armada DDS PhD Lúcio Souza GonçalvesFábio Ramôa Pires PhD 《Journal of endodontics》2014