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91.
Fifty one subjects who had pain involving the temporomandibular joint were evaluated using multidirectional tomography, arthrography, conventional nuclear scanning, and single photon emission computed tomography (SPECT) to assess the association of arthritis of the temporomandibular joint with internal derangements related to meniscal dysfunction. Five (56%) of the nine subjects who had normal arthrograms and normal multidirectional tomograms had SPECT scans that were positive for osseous changes. Twenty-two subjects (27 temporomandibular joints) were diagnosed by arthrography to have meniscal displacement with reduction. Multidirectional tomograms of the 27 joints were positive for osseous changes in five (18%) joints, whereas SPECT scans were positive in nine (70%) joints. Twenty subjects (20 temporomandibular joints) had an arthrographic diagnosis of meniscal displacement without reduction. Multidirectional tomograms of the 20 joints were positive for osseous changes in 14 (70%) joints, and SPECT scans were positive in 16 (80%) joints (P less than 0.001 vs control group). Initial observations with SPECT indicate it is a promising imaging method for detecting and staging osseous disease of the TMJ related to meniscal dysfunction.  相似文献   
92.
Sinus lift bone grafting has expanded the use of dental implants in reconstructions of the atrophic maxilla. Potential problems include sinus membrane tear, which can lead to graft infection and early failure. Attempts at managing sinus membrane perforations are often limited by difficulty of access, as well as by the friability of the soft tissue lining the sinus. Various techniques have been proposed for managing such membrane tears. The use of fibrin adhesive, however, may present a potential solution in such situations. This article reports our experience with the use of fibrin adhesive in sinus lift procedures, as well as on its autologous preparation.  相似文献   
93.
Objectives : An epidemiologic analysis was performed to identify patient and dentist factors influencing over- and undertreatment of restorative services in a sample of insured adults. Methods : At baseline, 681 Washington State employees and their spouses, aged 20 to 34 years and residing in the Olympia or Pullman areas, were interviewed by telephone. Oral assessments were conducted to measure personal characteristics, oral disease, and restoration quality. Adults were followed for two years to measure use of restorative services from dental insurance claims. Each adult's baseline and claims data were linked with provider and practice variables collected from the dentist who provided treatment. Results : For overtreatment, 39 percent of adults received one or more replacement restorations in nondecayed teeth with satisfactory fillings at baseline, while 18 percent of adults had one or more restorations placed in teeth with no decay and fillings. An adult's probability of overtreatment was higher if the adult had more fillings at baseline, or if an adult's dentist was younger, had a busy practice, advertised, charged higher fees, had less continuing education, or had a solo practice. For undertreatment, about 16 percent of adults either received no replacement restorations in teeth with unsatisfactory fillings at baseline, or had decayed teeth at baseline that were not filled or crowned. An adult's probability of undertreatment was higher if an adult had less decayed or more missing surfaces at baseline, or if an adult's dentist believed in sharing information with patients, had a busy practice, or reported not placing fillings when radiographic evidence of new caries was present. Conclusion : A minority of adults aged 20 to 34 experienced potential over- or undertreatment of restorative services, which are influenced by both patient and dentist factors.  相似文献   
94.
The microorganisms associated with mandibular third molar pericoronitis were investigated using direct microscopy and anaerobic culture method. The pericoronal pouch was sampled with paper points in A) 8 patients without mandibular third molar pericoronitis and B) 6 patients with mandibular third molar pericoronilis. Under the microscope, the microflora was found to be a complex mixture comprising gram-positive and gram-negative cocci, rods and filaments (including fusiform and curved rods), motile rods and spirochetes. Significantly higher proportions of motile, gram-negative rods were found in group B than in group A. The predominant cultivable microflora of 9 samples: A (4) and B (5) comprised several species of facultative and obligate anaerobic bacteria, namely Peptostreptococcus. Streptococcus, Actinomyces, Eubacterium, Propionibacterium, Veillonella, Porphyromonas, Prevotella, Bacteroides, Fusobacterium, Campylobacter, Staphylococcus, Stomatococcus, Lactobacillus, Neisseria, Capnocytophaga, Haemophilia, Selenomonas and Centipeda species. The microflora in pericoronitis appeared similar to that of diseased periodontal pockets.  相似文献   
95.
PURPOSE: The objectives of this investigation were to evaluate the effect of disinfection on surface quality and dimensional stability of more recent, reformulated vinylpolysiloxane (VPS) and polyether (PE) materials. METHODS: Using ANSI/American Dental Association (ADA) specification 19 protocols, 50 impressions of stainless steel dies were made with each material. Ten impressions of each material were randomly assigned to a treatment group: (1) no disinfectant; (2) 10-minute dual phenol immersion; (3) 1-hour dual phenol; (4) 10-minute sodium hypochlorite (NaOCl); and (5) 1-hour NaOCl. Impression surface quality immediately after disinfection was categorized as smooth/shiny, matte, or wrinkled/sticky. Dimensional stability was evaluated by measuring dimensional accuracy according to specification 19 after 24-hour, 1-week, and 2-week storage at ambient laboratory conditions. RESULTS: The PE material surface quality was significantly affected (Pearson Chi-square, p相似文献   
96.
97.
A 29-year-old Caucasian woman who presented with short stature and multiple unerupted supernumerary teeth is described. Radiological investigations of her cranial and skeletal abnormalities revealed cleidocranial dysplasia. Because of the advanced age of the patient and contraindication for orthodontic treatment, only surgical and prosthetic treatment were performed. The characteristics and treatments of this rare autosomal dominant disorder are discussed.  相似文献   
98.
A total of 40 patients with 46 fractures of the mandibular condylar process were examined an average of 47 months after the injury. The conventional radiologic examination consisted of panoramic radiography and lateral transcranial view of the fracture in the mouth-open and mouth-closed positions. Sixteen patients with 21 fractures of the condylar process were examined additionally by computed tomography (CT) because of temporomandibular joint problems in the sagittal and coronal projection. Computed tomography revealed bony changes in the fractured mandibular condyle and its position in the mandibular fossa more exactly than conventional radiographic examinations. Furthermore, the results showed that disturbances in the position and function of the articular disc may be more common than was earlier anticipated, suggesting the more frequent use of CT examinations to evaluate temporomandibular joint changes after condylar process fractures.  相似文献   
99.
One hundred and two Class IV cavities were restored randomly with four composite resins. The restorations were assessed at six months, one year, two years and three years for surface chipping, bulk fracture and incisal wear. The data were correlated with various mechanical properties of the materials. A significant correlation was found between surface chipping/bulk fracture and fracture toughness (P = 0.002), elastic modulus (P = 0.006) and tensile strength (P = 0.045). There was a trend towards an association between incisal wear and both elastic modulus and inherent flaw size. Fracture toughness may be a useful indicator of the clinical performance of composites in Class IV cavities.  相似文献   
100.
Dentists in the Philippines were surveyed for evidence of past hepatitis A and B virus infections. Of the 234 dentists examined, 201 (85.9 per cent) were found to have been infected by HA virus and 137 (58.5 per cent) had been infected by HB virus. The proportion with evidence of past HB virus infection increased as the years in dental practice increased. This increment with age was not found in the general population of the Philippines. It is considered that the incremental pattern could be attributed to the summation of risk during many years of providing dental treatment. Comparing the proportion of dentists with HBV antibodies (anti-HBs/c) in the Philippines, Japan, USA and Denmark, the Philippine dentists were found to be more frequently infected than dentists in the other countries. However, the increment in the proportion positive for HBV as the years in practice advanced was consistent with that found in Japan. The prevalence of post HA virus infection in Philippine dentists was higher than the proportion for dentists in Japan but in both countries it is probable that dentists are infected at the same rate as the general population.  相似文献   
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