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961.
Follow-up study of endodontic status in an adult Swedish population.   总被引:1,自引:0,他引:1  
The purpose of this study was to examine changes in the endodontic status of selected teeth in a population over time, in order to get a long-term perspective of endodontically treated teeth. A random sample of the adult Swedish population was selected in 1974 and offered a clinical and radiographic examination. Eleven years later 351 of the selected persons attended a follow-up examination (1985). In radiographs, covering the mandibular premolar and molar regions, the status of 1974 was directly compared, tooth by tooth, with the status of 1985. The results showed that a number of endodontically treated teeth with an apical periodontitis healed during the observation period. During the same period, approximately the same number of endodontically treated teeth presented with a new apical periodontitis. This finding suggested that cross-sectional studies could provide reliable information on the long-term success rate of endodontic treatment at the population level. The periapical lesions that persisted or developed during the observation period were strongly related to incomplete root canal obturation, which is in agreement with observations in follow-up studies from teaching and specialist clinics.  相似文献   
962.
A case of an atypical odontogenic tumor with features of unicystic plexiform ameloblastoma and odontoblastic differentiation with deposition of tubular dentin matrix is reported. The significance of dentinogenesis, amelogenesis, and calcification in odontogenic tumors is discussed.  相似文献   
963.
Tooth diameters and arch perimeters in a black and a white population   总被引:1,自引:0,他引:1  
This study was undertaken to test the hypothesis that a sample of black patients will have larger mesiodistal tooth diameters and larger dental arch perimeters than a corresponding sample of white patients. In this study, the black sample's mean canine, first and second premolar, and first molar mesiodistal diameters were significantly larger than those of the white sample. The dental arches of the black patients were significantly wider and deeper but did not show significantly more crowding. Gender and race differences did exist, but gender differences were controlled by sampling procedures. The black sample also had a larger mean MP-SN angle but this was not accompanied by the increased crowding and the narrower dental arches that had been reported associated with high-angle white samples.  相似文献   
964.
Abstract The purpose of this study was to examine changes in the endodontic status of selected teeth in a population over time, in order to get a long-term perspective of endodontically treated teeth. A random sample of the adult Swedish population was selected in 1974 and offered a clinical and radiographic examination. Eleven years later 351 of the selected persons attended a follow-up examination (1985). In radiographs, covering the mandibular premolar and molar regions, the status of 1974 was directly compared, tooth by tooth, with the status of 1985. The results showed that a number of endodontically treated teeth with an apical periodontitis healed during the observation period. During the same period, approximately the same number of endodontically treated teeth presented with a new apical periodontitis. This finding suggested that cross-sectional studies could provide reliable information on the long-term success rate of endodontic treatment at the population level. The periapical lesions that persisted or developed during the observation period were strongly related to incomplete root canal obturation, which is in agreement with observations in follow-up studies from teaching and specialist clinics.  相似文献   
965.
Craniomandibular disorders are conditions encompassing various types of dysfunction of the stomatognathic system. To define the very nature of morbidity, both differential and pathological diagnosis are absolutely necessary. At present, each medical institution in this country has its own protocol for evaluating and treating craniomandibular disorders. This makes it difficult to exchange and compare data between institutions. In this paper, a protocol worked out by our department after a series of clinical tests and study is presented, and its merits and unresolved problems are discussed.  相似文献   
966.
967.
Neuropeptide K-like immunoreactivity in human dental pulp   总被引:1,自引:0,他引:1  
Nerve fibres displaying such immunoreactivity were revealed by indirect immunofluorescence. Neuropeptide K-like immunoreactive fibres, entering the pulp within large nerve trunks, were distributed around blood vessels as well as in the stroma. Some immunoreactive fibres were also observed in the para-odontoblastic region. In view of the biological activity of neuropeptide K, it is tentatively proposed that it may act in the dental pulp as a regulatory peptide involved in neurogenic inflammation, blood flow regulation and sensory transmission.  相似文献   
968.
The in vitro sealing ability of the root-canal sealer Diaket when used as a root-end filling material was compared with that of amalgam using linear microleakage of Indian ink. Eight groups of 20 extracted teeth each were formed, plus 12 control teeth as follows: 1) root-end resection of 45° bevel, root-end cavity preparation with an 008 round bur, amalgam root-end filling; 2) 45° bevel, bur, Diaket; 3) 45° bevel, using a sonic retro-prep tip, amalgam; 4) 45° bevel, sonic, Diaket; 5) no bevel, bur, amalgam; 6) no bevel, bur, Diaket; 7) no bevel, sonic, amalgam; 8) no bevel, sonic, Diaket. Root-end cavity depths of 3 mm were prepared. Specimens were immersed in Indian ink for 2 weeks. The teeth were demineralized, rendered transparent and linear dye penetration recorded. Results showed that Diaket provided a superior seal to amalgam irrespective of the root-end preparation. The degree of bevel of the resected root-end did not influence leakage. Sonic instrumentation resulted in a larger root-end cavity than with burs.  相似文献   
969.
The single tooth implant is a treatment option for the replacement of missing single teeth and in many cases is the treatment of choice. It is, however, an expensive treatment requiring a co-ordinated approach to the surgical and restorative aspects of treatment. In this study, a group of dentists in general and restorative dental practice and with no previous experience in implant surgery underwent an intensive training course in all aspects of implant treatment for single teeth. Using a system of simplified instrumentation with a strict adherence to protocol, the group installed and restored single tooth implants ad modum Brånemark in a wide range of clinical situations. At the one year follow-up period following crown insertion, the success rate of treatment compared favourably with results reported from centres using the specialist team approach to treatment. The results of this study indicate that further consideration should be given to the training of general dentists so that improved delivery of dental health care can be provided at a more economic level.  相似文献   
970.
Sub-gingival microflora in Macaca mulatta species of rhesus monkey   总被引:1,自引:0,他引:1  
The Macaca mulatta species of rhesus monkey is one of several non-human primate (nhp) models for periodontal disease. This report presents the bacteriology of the gingival sulci in M. mulatta monkeys. Three sub-gingival sites (maxillary right central incisor, the disto-buccal of the mandibular left second molar and mesio-buccal of the mandibular right second molar) of 9 monkeys were evaluated clinically before scaling and 7 days after scaling. Plaque samples were obtained from sub-gingival sites before clinical examination and studied bacteriologically by dark field microscopy, selective and non-selective culture, and by primary phenotypic characterizations of culture isolates. Several gingival sites presented with mild gingival inflammation. Anaerobic and facultatively anaerobic bacteria were the predominant flora colonizing the gingival sulci. The major microbial groups were Haemophilus species (100% of sites; percentage of total anaerobic count (TAC); 21-51), Peptostreptococcus micros (89%, 7.5–29.5), Actinomyces sp. (85%, 7–27), Fusobacterium nucleatum (90%, 5–8), Actinobacillus actinomycetemcomitans (73%, 1.3–12), black-pigmented anaerobic rods ( BPAR ) (80%, 0.6–6.5) and oral streptococci (80%, 0.2–1.0). Microbial groups detected less often were Wolinella sp. (66%, 0–2.6), Capnocytophaga sp. (30%), Eikenella corrodens (4.7%, 0), Campylobacter sp. (28%, 0–0.1) and spirochetes (4.7%, 0–0.07). Seven days after gingival sites were scaled, the plaque score and indices for gingival inflammation declined significantly. The gingival flora after scaling were characterized by lower proportions of the Actinomyees sp., P. micros and BPAR; and increased proportions of the oral streptococci, relative to pre-scaling levels. The major microbial groups at scaled gingival sites were the Haemophilus sp., oral streptococci, F. nucleatum and A. actinomycetemcomitans. The mutual proportions of microbial groups varied non-significantly within gingival sites and between monkeys. In conclusion, the M. mulatta gingival sulci are colonized by microbial species that resemble putative pathogens of periodontal disease, and the composition and character of the gingival flora are similar to the gingival flora of other Old World monkey models.  相似文献   
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