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31.
Seventy dental students (mean age: 20 years) with 130 asymptomatic, non-ectopic, impacted mandibular 3rd molars were followed for 4 years. At the initial visit 26 were impacted in soft tissue, 30 were partially impacted in bone, and 74 were completely impacted in bone. The following items were registered at each visit: regional pocket depths, signs and symptoms of pathology, degree of impaction, presence of upper 3rd molar. No signs or symptoms of pathology were observed in any of the subjects at the 2 visits. The 4-year visit revealed that 49 3rd molars had been removed, the reason being pericoronitis or caries in 30%, mild symptoms in 39% and for prophylactic reasons in 31%. Of the remaining 81 3rd molars: 71% of the soft tissue impactions, 25% of partial bony impactions, and 8% of complete bony impactions showed complete and normal eruption. The remaining 3rd molars were either static or had advanced in the degree of eruption. It is concluded that non-ectopic, impacted 3rd molars in the given age group may have a chance to completely erupt. The treatment for asymptomatic impacted 3rd molars in young adults, therefore, might be observation instead of prophylactic removal.  相似文献   
32.
Whereas the prosthetic treatment of an edentulous cleft patient with timely closure of the cleft promises to yield good results, the rehabilitation of an edentulous cleft patient with open cleft makes special demands on the prosthetist. Separate impressions for the denture and the obturator have proved a success at the Rostock University Clinic. On the basis of personal experience and results from re-examinations, the authors emphasize the value of regular ambulatory supervision.  相似文献   
33.
Five patients with orofacial infection which failed to respond to penicillin therapy are described. In each instance, β-lactamase producing Bacteroides strains were found. All strains were resistant to penicillin but sensitive to clindamycin and tinidazole. In two cases, extended surgical treatment cured the patient, but in the other three cases additional clindamycin therapy was required.  相似文献   
34.
The formation of a salivary pellicle is a protective mechanism of the body for all surfaces in the oral cavity. The nature of the substrate may influence the composition of the pellicle. The aim of this study was to investigate the quantitative composition and individual variation of the salivary pellicle formed on denture base material (PMMA). Cylindrical specimens of PMMA were carried in the mouth and then desorbed with a 0.5-M sodium chloride solution. The solution was analysed for total protein, alpha-amylase, total proteases, protease inhibitors, secretory immunoglobulin A, immunoglobulin G, peroxidases, thiocyanate, lysozyme, and calcium content. All investigated salivary components could be found unequivocally in the desorption solution, indicating that a salivary pellicle had formed on the surface of the PMMA. Large coefficients of variation indicate large individual variations in the adsorbed amounts. The data also point to large intraindividual variations for the bound salivary components. Only the protease inhibitors revealed a strong positive correlation of the bound activity to the salivary activity. It is hypothesised that differences in the bound amounts of antimicrobial components might influence the microbial colonisation of denture bases and that protease inhibitors could be meaningful for the spread of the yeast Candida albicans from denture base material to the oral mucosa and thus might be an explanation for different susceptibility to denture base stomatitis.  相似文献   
35.
AIM: The aim of the present study was to assess the reproducibility and validity of linear measurements of interproximal bone loss in intrabony defects on digitized radiographic images after application of different filters and magnifications. METHODS: Immediately before surgery 50 radiographs of 50 periodontally diseased teeth exhibiting interproximal intrabony defects were obtained by a standardized technique in 50 patients. Intrasurgically the distances from the cementoenamel-junction (CEJ) to the alveolar crest (AC) and from the CEJ to the deepest extension of the bony defect (BD) were assessed. All radiographs were digitized by a flatbed scanner (resolution: 600x1200 dpi). Using the FRIACOM-soft ware, the linear distances CEJ to AC and CEJ to BD were measured at 50 intrabony defects on digitized but unchanged radiographic images and also after use of 2 different basic image processing modes (filters: enhancement of grey level differences, spreading of grey values) with 7-fold and 14-fold magnification by 2 different examiners. RESULTS: Repeated measures MANOVA revealed reproducibility of the measurement of the distance CEJ to AC to be significantly influenced by examiner (p=0.027) and filter in combination with the height of 2 wall component of the intrabony defect (p=0.066). For the distance CEJ to BD filters had significant influence on reproducibility in correlation with vertical angulation difference (p=0.001). On the average in this study radiographic measurements tended to overestimate the amount of bone loss as assessed by intrasurgical measurements (CEJ-AC: 0.74-1.91 mm; CEJ-DB: -0.04-0.77 mm). Validity of measurement of the distance CEJ-AC was shown to be significantly influenced by the depth of the intrabony defect (p<0.003). Validity of the distance CEJ-BD was significantly influenced by intrasurgically assessed bone loss (p=0.029), horizontal angulation (p=0.066). Filters influenced the validity only in combination with examiner (p<0.001). CONCLUSIONS: In this study, the chosen digital manipulations (filters: spreading, structure) of radiographic images failed to result in statistically significantly more reproducible or valid measurements of interproximal bone loss within intrabony defects when compared to the digitized but unchanged images. All radiographic assessments on the digitized images except for use of enhancement of grey level differences (structure) came close to the intrasurgical gold standard.  相似文献   
36.
The topographic relationship of the apices of the primary teeth to the permanent tooth germs explains the potential for possible developmental disturbances of the permanent teeth after injuries to their predecessors. The anatomical, histologic and clinical aspects of permanent tooth malformation following trauma to the primary teeth are described. One hundred and fourteen children with originally 255 traumatized primary teeth have been re-examined (with an average period of 5.1 years after the trauma) to assess any developmental disturbances of the corresponding permanent teeth. Twenty-three per cent of partially or completely erupted permanent teeth showed developmental disturbances. The most frequent malformation was enamel hypoplasia including enamel discoloration and/or enamel defects. The highest prevalence of developmental disturbances of permanent teeth was found after intrusive injuries of primary teeth.  相似文献   
37.
The present study assessed the progression rate of periodontal disease over 8 years in a group of 52 adult patients with various forms of cleft lip, alveolus, and palate considered at risk for progression of periodontal disease. Of special interest was the evaluation of periodontal disease progression at sites adjacent to cleft regions compared to changes found at control sites not directly affected by such defects. High incidences of generalized plaque accumulation and bleeding on probing were noted at both examinations in 1979 and 1987. A mean apical shift of the clinical attachment level amounting to 0.2 mm had occurred over the 8-year observation period. A slight apical displacement of the mesial and distal mean crestal alveolar bone was also noted. The rate of progression of periodontal disease over the 8 years was not found to be different at statistically significant levels at cleft sites compared to control sites. However, the results of this study documented that the cumulative periodontal destruction at 26 to 28 years of age was statistically significant and more pronounced at cleft sites as revealed by greater probing pocket depth and loss of clinical attachment. The differences between test and control sites amounted to 0.3 and 0.4 mm respectively for probing depth and 0.6 mm for loss of clinical attachment. In addition, the discrepancy between alveolar bone height and the levels of the clinical attachment at cleft sites demonstrated the presence of a long supracrestal connective tissue attachment adjacent to cleft defects. Therefore, the alveolar bone height as visualized in radiographs at such sites was considered an unreliable diagnostic tool for the assessment of the degree of periodontal destruction.  相似文献   
38.
Abstract –  Trauma to the primary dentition present special problems and the management is often different as compared with permanent teeth. An appropriate emergency treatment plan is important for a good prognosis. Guidelines are useful for delivering the best care possible in an efficient manner. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases in which the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the current best evidence based on literature research and professional opinion. In this third article out of three, the IADT Guidelines for the management of traumatic injuries in the primary dentition, are presented.  相似文献   
39.
This review comprises a short summary of up-to-date clinical knowledge on systemic osteoporosis in order to focus on the clinical dental studies on osteoporosis of the jaws, which have become available within the last 15 years. Diagnosis of jaw osteoporosis requires assessment of the bone mineral content (BMC)/density (BMD) using specially constructed jaw bone scanners and development of a corresponding gender-related set of normal BMC/BMD values for young adults, as in other sites of the skeleton. If other factors are excluded, jaw osteoporosis may involve the risk of minor accentuation of alveolar bone loss after wearing a full denture, in cases of periodontitis and in peri-implant areas. However, implant-supported overdentures conserve bone because of their positive load-related effect on the jaw. Estimation of BMC/BMD is also advisable for edentulous osteoporotic patients. Systemic treatment involving the bone metabolism affects the jaw BMC/BMD positively or negatively as in other skeletal sites, but the magnitude of this effect is site-specific. Future studies of the effect of bisphosphonates on the jaw BMC and alveolar bone loss, and analyses of the bone quality and jaw BMC/BMD in relation to implant treatment, without or with bone transplantation, are required.  相似文献   
40.
The β1-integrins (VLA family) are cellular adhesion molecules (CAM) that play a major role in cell-cell and cell-matrix interactions. The expression pattern of CAM was studied in 5 clinically normal volunteers with healthy gingiva and in 18 patients with clinically different stages of periodontitis. In healthy human gingiva α2. α3 and α6 integrin chains were found in a characteristic distribution, showing a broad continuous expression on the junctional and sulcular epithelium sites. The expression of these integrins was demonstrated primarily on the basal cell layers and in some cells of the stratum spinosum. Inflammatory stages of periodontitis revealed further upregulation of α2, α3 and α6 integrins into the junctional and sulcular epithelial cells, which correlated with the stage of the periodontitis and the extent of the cellular infiltration. α4 and α6 were found to be the predominant β1 integrin chains on inflammatory cells. The amount of δ4 and ş6 positive infiltrative cells increased with the number of inflammatory cells. VCAM-1. the corresponding cell-cell ligand of VLA-4 (α4) was present on the majority of subepithelial vessels in all stages of gingivitis and periodontitis. The α5 subunit was expressed on both endothelium and gingival connective tissue cells. Samples from advanced periodontitis cases showed a higher number of a5 positive mononuclear cells. In comparison to normal epidermis, a human gingival epithelial cells express higher levels of integrins. This expression is further upregulated in advanced stages of periodontitis, indicating changes of the β1 integrin organization.  相似文献   
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