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991.
AIMS: To assess the impact of two methods of brief nurse-delivered brief interventions in reducing drinking variables in hazardous drinkers with alcohol-related facial injuries. METHODS: A randomised controlled trial of two brief interventions involving hazardous drinkers with facial trauma in three Oral and Maxillofacial Surgery outpatient clinics in the West of Scotland; 194 patients were recruited and randomised to have either a nurse-led brief motivational intervention (intervention group) or a leaflet about alcohol misuse (control group). Patients were followed up at 3 and 12 months after the intervention and drinking variables reassessed. RESULTS: A brief motivational intervention for alcohol provided by a nurse was more effective than a leaflet in helping some patients with facial trauma to reduce their alcohol consumption 12 months after the intervention (p<0.05). CONCLUSIONS: Facial trauma in the West of Scotland is strongly associated with alcohol misuse and is a recurrent disease, particularly among those who drink heavily. A nurse-delivered brief motivational intervention is effective in helping patients with high scores in the Alcohol Use Disorders Identification Test to reduce their drinking, and this effect was apparent 12 months after the intervention.  相似文献   
992.
AIM: To assess the efficacy of a medicated dressing in the socket on the healing after dental extractions in HIV positive patients. PATIENTS AND METHODS: Forty HIV positive patients with CD4 counts below 200 cells/mm(3) who were to have molar teeth extracted were randomly allocated to have the socket dressed with a medicated paste (Rifocort) with camphorated parachlorophenol and iodoform) and sutured (treated group), or merely sutured (control group). RESULTS: The sockets in the treated group healed more quickly than in the control group.  相似文献   
993.
The purpose of this study was to determine whether 12.5 MHz ultrasonography (US) could be used to assess the presence or absence of temporomandibular joint (TMJ) internal derangement (ID). In 48 consecutive patients with TMJ disorders 192 TMJ positions were investigated by US to analyse the functional disc-condyle relationship (DCR). In order to compare the respective findings with those of a diagnostic method offering a high accuracy, coronal and sagittal magnetic resonance imaging was carried out immediately afterwards. With US showing a sensitivity of 0.58 and 0.75, and a specificity of 0.92 and 0.84 for disc displacement with and without reduction, the data revealed US to be marginal in detecting the presence, but sensitive in detecting the absence of the respective types of a TMJ ID. In addition, with a positive predictive value of 0.83 and 0.71, and a negative predictive value of 0.81 and 0.87 for disc displacement with and without reduction, the results indicate that US may be insufficient in establishing a correct diagnosis for the presence or absence of the respective types of TMJ ID. Regarding the diagnosis of absence or presence of TMJ ID, the results demonstrate high-resolution (HR)-US to be sensitive in detecting the absence, and reliable in predicting the presence of TMJ ID. In view of the fact that the 12.5 MHz US technique proved to be a reliable diagnostic aid for the detection of normal, and the prediction of abnormal DCR, the results of this study should be of further interest and encourage research in its potential uses and diagnostic capabilities.  相似文献   
994.
OBJECTIVES: This study compared the influence of different inner crown surfaces on the fracture resistance and marginal adaptation of adhesively fixed glass fibre-reinforced molar crowns. MATERIALS AND METHODS: Vectris/Targis crowns were constructed with an inner framework of glass fibres (directly on the tooth) or an inner veneering composite layer between the fibre-framework and the tooth-substance. Both groups were sandblasted inside using Al(2)O(3); 50 microm grain size (200 kPa, 20 s) and silane coated. A control group had the inner fibre framework, but was neither sandblasted nor silane coated. The crowns were adhesively cemented on extracted human teeth, and thermally cycled and mechanically loaded (TCML: 6000 x 5 degrees C/55 degrees C; 1.2 x 10(6) x 50 N, 1.66 Hz). The marginal adaptation before and after TCML was evaluated and the fracture resistance was investigated using a Zwick universal testing machine. RESULTS: After TCML the proportion of 'perfect margin' of the control group decreased significantly at the interface crown/cement. For the variations with an inner fibre framework or inner composite layer the marginal adaptation or fracture resistance did not decrease significantly after ageing. The fracture resistance values were control: 1509N+/-486; inner fibre framework: 1896N+/-342; inner composite layer: 1754N+/-340. CONCLUSIONS: In the case of the investigated fibre framework and veneering composite, the inner surface of glass fibre-reinforced molar crowns can be covered with a composite layer or with a glass fibre framework. Both methods achieve comparable high fracture strengths and reliable marginal adaptation.  相似文献   
995.
AIM: To investigate a number of clinical and treatment variables that might have influenced the prevalence of apical periodontitis in root-filled teeth in a population of periodontally compromised patients. METHODOLOGY: This investigation was a retrospective cross-sectional study on data collected from periodontal charts in addition to intra-oral full-mouth radiographs from patients attending the Department of Periodontology of the Dental School of the Ghent University Hospital. Periodontal parameters (clinical attachment loss and the lowest marginal bone level, the history of periodontal treatment), endodontic treatment (length, homogeneity and overall quality of the root filling) and the quality of coronal restorations were related to the prevalence of apical periodontitis. A total of 272 root-filled teeth in 94 patients were evaluated. RESULTS: The periapical condition was significantly influenced by the quality of the root filling and the coronal filling (P < 0.05). More apical periodontitis was seen when the coronal level of the root filling exceeded the marginal bone level (P < 0.005). The marginal periodontal condition seemed to influence the periapical status. Teeth with apical periodontitis were associated with significantly more extended marginal bone loss (P < 0.001). Significantly less apical periodontitis was seen in patients that had received marginal periodontal treatment (P < 0.005), compared with untreated periodontal patients. CONCLUSIONS: Signs of periodontal disease, as reflected by marginal bone loss, are of importance for the periapical condition of root-filled teeth. Efforts should be taken in preventing spread of infection through the periodontal-endodontic pathway by periodontal infection control and a high quality of root filling and coronal filling. Care should also be taken to seal the coronal cavity up to the level of the root filling, where it is advisable to reduce the coronal level of the root filling below or at least at the level of the surrounding marginal bone.  相似文献   
996.
AIM: To determine how instrument design affects the fatigue life of two nickel-titanium (Ni-Ti) rotary systems (Mtwo and ProTaper) under cyclic fatigue stress in simulated root canals. METHODOLOGY: Cyclic fatigue testing of instruments was performed in stainless steel artificial canals with radii of curvature of 2 or 5 mm and an angle of curvature of 60 degrees . A total of 260 instruments were rotated until fracture occurred and the number of cycles to failure were recorded. The morphology of Ni-Ti rotary instruments was investigated by measuring the volume of millimetre slices of each instrument size starting from the tip to the shank by means of microCT analysis. The fracture surface of three representative samples of each size was analysed by scanning electron microscopy (SEM). Data were analysed by one-way anova, Holm t-test, paired t-test and linear regression; the significance was determined at the 95% confidence level. RESULTS: Cycles to failure significantly decreased as the instrument volume increased for both the radii of curvature tested (P < 0.01). The radius of curvature had a statistically significant influence on the fatigue life of the instruments (P < 0.05). Larger instruments underwent fracture in less time under cyclic stress than smaller ones. SEM evaluation showed typical features of fracture through fatigue failure. CONCLUSIONS: The metal volume in the point of maximum stress during a cyclic fatigue test could affect the fatigue life of Ni-Ti rotary instruments. The larger the metal volume, the lower the fatigue resistance.  相似文献   
997.
A 17-year-old white boy with signs, symptoms, and family history of angiokeratoma corporis diffusum universale, Anderson-Fabry disease (AFD), developed recurrent and then persistent swelling of both lips, erythematous hyperplastic gingivae, and a pebbled tongue. Positive blood findings were raised serum IgE, decreased T-cell level, and increased B-cell level. Histopathology of the gingiva showed noncaseating granulomas with multinucleate giant cells containing Schaumann bodies and large plasma-cell infiltrates in which immunofluorescence demonstrated immune globulins of several classes. Electron microscopy and histochemistry demonstrated ceramide in the vasculature. No glycolipid was found in the macrophages or giant cells of the granulomas which, in contrast, resembled sarcoid reactions. Plasma cells with Russell bodies and immune reaction-induced degranulation of mast cells were also identified. The pathogenesis of the oral findings possibly relates to altered immune reactivity associated with damage to the microvasculature analogous to that in Melkersson-Rosenthal syndrome.  相似文献   
998.
Human dentine was demineralized and exhaustively extracted with EDTA, then extracted successively with 8 M urea, alkaline potassium chloride and 8 M urea with 0.1 M sodium borohydride. The insoluble residue was treated with sodium periodate. Acidification of the periodate-solubilized material resulted in only minimal amounts of precipitate which appeared to be entirely collagenous. Fractionation of the soluble material by ion-exchange chromatography and gel-filtration resulted in the isolation of five fractions. Two were collagenous, one a non-collagenous protein and two appeared to comprise collagen fragments attached to non-collagenous moieties. These latter fractions were digested with collagenase resulting in the appearance of two similar non-collagenous proteins. The insoluble residue after periodate treatment was subjected to collagenase digestion and the soluble non-dialysable products fractionated by ion-exchange chromatography. The resulting fractions all appeared to consist of collagen fragments attached to non-collagenous proteins. No evidence of a collagen-bound phosphoprotein in human dentine could be found.  相似文献   
999.
To ensure eruption of the dentition in patients with cleidocranial dysostosis, close collatoration between the oral surgeon and the orthodontist is essential to determine the sequence of extraction, the teeth to be ligated, the preferred technique of ligation, and the approach for surgical exposure.  相似文献   
1000.
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