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991.

Objective

The objective of this prospective clinical trial was to evaluate the 4-year clinical performance of an ormocer-based nano-hybrid resin composite (Ceram X; Dentsply/DeTrey) in Class II restorations placed with a one-step self-etch (Xeno III; Dentsply/DeTrey) and two-step etch-and-rinse adhesive (Ivoclar Vivadent).

Methods

Seventy-eight participants received at random at least two, as similar as possible, Class II restorations of the nano-hybrid resin composite bonded with either a single step self-etch adhesive or a control 2-step etch-and-rinse adhesive. The 165 restorations were evaluated using slightly modified USPHS criteria at baseline and then yearly during 4 years.

Results

162 restorations were evaluated at 4 years. Postoperative sensitivity was observed in 6 patients (3 Xeno III, 3 Exite) between 1 and 3 weeks. Eleven failed restorations (6.8%) were observed during the follow up. Seven in the one-step self-etch adhesive group (7.7%) and four in the 2-step etch-and-rinse group (5.6%). This resulted in non-significant different annual failure rates of 1.9% and 1.4%, respectively. Fracture of restoration was the main reason for failure.

Conclusion

The ormocer-based nano-hybrid resin composite showed a good clinical performance in Class II cavities during the 4 year evaluation. No significant difference was seen in overall clinical effectiveness between the two adhesives.  相似文献   
992.
This study was designed to evaluate in vitro the efficacy of a novel at-home bleaching technique using 10% or 16% carbamide peroxide modified by casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and its influence on the microhardness of bleached enamel. A total of 40 bovine incisors were divided into four groups (n=10) according to the bleaching agent used: 10% carbamide peroxide only; a blend of 10% carbamide peroxide and a CPP-ACP paste; 16% carbamide peroxide only; and a blend of 16% carbamide peroxide and a CPP-ACP paste. During the 14-day bleaching regimen, the samples were stored in artificial saliva. The Vickers microhardness and color of the teeth were assessed at baseline (T0) and immediately after the bleaching regimen (T14) using a microhardness tester and a spectrophotometer, respectively. The degree of color change was determined by the Commission Internationale de l'Eclariage (CIE) L*a*b* system (ΔE, ΔL*, Δa*, and Δb*) and Vita shade guide parameters. The data were analyzed by analysis of variance and the Tukey test (p<0.05). The teeth that were bleached with a blend of peroxide (10% or 16%) and the CPP-ACP paste presented increased microhardness values at T14 compared with T0, whereas the samples that were bleached with peroxide only did not show any differences in their microhardness values. All of the bleaching agents were effective at whitening the teeth and did not show a statistically significant difference using the CIEL*a*b* system (ΔE, ΔL*, Δa*, and Δb*) or the Vita shade guide parameters. The use of a CPP-ACP paste with carbamide peroxide bleaching agents increased the bleached enamel's microhardness and did not have an influence on whitening efficacy.  相似文献   
993.
The aim of the investigation was to collect information from specialized hospitals regarding dental care before and after organ transplantation or replacement of prosthetic joints. 50 transplantation centres and 100 orthopaedic hospitals in Germany were chosen. A questionnaire was used to elucidate the following aspects: Is a dental examination carried out preoperatively? When the patient is discharged, is he or she recommended to have antibiotic prophylaxis before dental treatment? If so, which antibiotic is recommended? The response rate was 56% (n = 28) for transplantation centres. 89% arranged a dental examination before the transplantation. 83% of those questioned recommend antibiotic prophylaxis before dental treatment: Amoxicillin was mentioned most frequently (36%). The response rate of the orthopaedic hospitals was 31% (n = 31). 3% of those questioned arranged a dental examination before insertion of an endoprothesis. 55% recommend antibiotic prophylaxis when dental treatment is to be carried out following the insertion of the endoprosthesis. Cephalosporine was most frequently mentioned (33%). It was not possible to identify a uniform recommendation regarding dental care before and after organ transplantation or replacement of prosthetic joints either for patients with an organ transplant or those having a prosthetic joint.  相似文献   
994.
Saygun I, Nizam N, Keskiner I, Bal V, Kubar A, Aç?kel C, Serdar M, Slots J. Salivary infectious agents and periodontal disease status. J Periodont Res 2011; 46: 235–239. © 2011 John Wiley & Sons A/S Background and Objectives: The potential of salivary microorganisms to diagnose periodontal disease and to guide periodontal treatment is a research topic of current interest. This study aimed to determine whether the salivary counts of periodontopathic microbes correlated with the periodontal pocket counts of the same infectious agents, and whether the salivary counts of the test infectious agents could distinguish among individuals with periodontal health and various types of periodontal disease. Material and Methods: The study included 150 systemically healthy adults, of whom 37 were periodontally healthy, 31 had gingivitis, 46 had chronic periodontitis and 36 had aggressive periodontitis. Each study subject contributed microbial samples from the two deepest periodontal pockets of the dentition and from whole saliva. Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Epstein–Barr virus were identified using the TaqMan real‐time PCR methodology. Statistical analysis was performed using the Mann–Whitney U‐test and the receiver operating characteristic statistics. Results: C. rectus, F. nucleatum, P. gingivalis, P. intermedia and T. forsythia occurred with significantly higher copy‐counts in salivary samples from patients with gingivitis, chronic periodontitis and aggressive periodontitis than from periodontally healthy individuals. A. actinomycetemcomitans only showed higher salivary copy‐counts in subjects with aggressive periodontitis compared with subjects with healthy periodontium, and the salivary copy‐counts of Epstein–Barr virus did not reveal any significant difference among the four subject groups studied. The diagnostic sensitivity for periodontitis was 89.19 for P. gingivalis and for T. forsythia and 86.49 for P. intermedia, with specificities ranging from 83.78 to 94.59. The optimal copy‐counts per mL saliva for identifying periodontitis were 40,000 for P. gingivalis, 700,000 for T. forsythia and 910,000 for P. intermedia. Conclusion: Salivary copy‐counts of P. gingivalis, T. forsythia and P. intermedia appear to have the potential to identify the presence of periodontitis, whereas the salivary level of the other test infectious agents may possess little or no diagnostic utility. Longitudinal studies are warranted to determine the ability of salivary copy‐counts of major periodontopathic bacteria to predict future periodontal breakdown.  相似文献   
995.
Headache and facial pain are both very high in the general population. Headache has been identified as one of the associated conditions in patients with chronic orofacial pain. The interrelation between the two has not been explored in the literature. Patients with facial pain often initially seek the care of a dentist. Misdiagnosis and multiple failed treatments (including invasive procedures) are very common in this population. This case report describes four patients whose condition fulfilled the International Headache Society's criteria for hemicrania continua but whose teeth were extracted because their pain was suspected to be of odontogenic origin. Each patient's records and the literature were reviewed for possible reasons for the unnecessary extractions. The findings suggest that initial treatment with drugs specific for primary headache disorders should be instituted before subjecting patients to invasive procedures.  相似文献   
996.

Objective

This in vitro study evaluated the effects of a zinc oxide eugenol (ZOE) base on the mechanical properties of a composite resin restoration.

Methods

Class I cavities were prepared on plastic teeth and filled with ZOE plus composite resin, following standard clinical procedures. The samples were sectioned sagittally and the ZOE–resin interface was exposed. After polishing, nanoindentation was performed on the region near the interface, and elastic modulus and hardness were plotted in the form of a color contour map. SEM was employed to observe the interface between composite resin and ZOE base.

Results

In the region close to the ZOE base, the elastic modulus and hardness of composite resin reduced to the values of 9.71 ± 0.54 and 0.51 ± 0.05 GPa, respectively. Eugenol from ZOE had detrimental effects on the composite resin only to a distance of less than 100 μm from the ZOE base.

Conclusion

Although eugenol suppresses polymerization slightly, by considering the biological advantages of ZOE, together with the results of the current investigation, ZOE may still be considered a suitable base material for composite resin. Bonding is essential for composite resin restorations over ZOE bases to avoid shrinkage detachment.  相似文献   
997.
OBJECTIVE: This study was designed to investigate the effectiveness of topical bupivacaine (0.25%) in reducing postoperative distress following extraction of teeth under general anaesthesia in children. DESIGN: The study was a double-blind randomized controlled trial. SETTING: The study was conducted in a dental hospital. SAMPLE: The sample comprised 135 children aged between 2 and 12 years of age who were undergoing outpatient general anaesthesia for simple dental extractions. METHODS: The children were randomly allocated to one of two groups: the bupivacaine group (the study group) comprised 68 children whilst the sterile water group (the control group) comprised 67. Following the extraction of their teeth, children had swabs soaked in the appropriate solution placed over the exposed teeth sockets. A five-point face scale was employed by an independent observer to evaluate the distress for each child. Evaluation of distress was made preoperatively, on recovery from the general anaesthetic, and again, 15 min following recovery from the anaesthetic. RESULTS: There were no statistically significant differences between the mean distress scores for the bupivacaine and sterile water groups preoperatively, postoperatively or 15 min postoperatively. For both groups, however, there were significant increases in distress scores between the preoperative and 15 min postoperative assessment scores. CONCLUSION: Extraction of teeth under general anaesthesia does cause distress in children. There is no evidence that topical bupivacaine reduces this distress when compared to sterile water.  相似文献   
998.
Kok YV  Mageson P  Harradine NW  Sprod AJ 《Journal of orthodontics》2004,31(4):312-8; discussion 300-1
OBJECTIVE: To compare the use of the Aesthetic Component (AC) of IOTN and the Child Perceptions Questionnaire (CPQ) in assessing orthodontic treatment need and concern. DESIGN: Cross-sectional observational study. SUBJECTS AND METHODS: The subjects were 204 children aged 10-12 years studying in 10 schools in Bristol, UK. They completed a questionnaire comprising the CPQ and questions regarding orthodontic concern. AC scores as rated by the child and by the calibrated examiner were recorded. MAIN OUTCOME MEASURES: CPQ scores were calculated from the responses in the questionnaire. AC scores and responses to questions regarding orthodontic concern were recorded. RESULTS: The children gave themselves lower AC scores compared to the examiner (p<0.001).The only section of the CPQ that correlated significantly with Examiner AC was the emotional impacts section (rho=0.151). CPQ scores had a slightly higher correlation with self-perceived AC than Examiner AC. However, the correlations were still very low. The emotional impacts section of CPQ (rho=0.332) and overall CPQ score (rho=0.282) were better than the examiner AC (rho=0.209) at reflecting how bothered the children were by the alignment of their teeth, and how upset they would be if they couldn't receive orthodontic treatment (rho=0.464, 0.428 and 0.214, respectively). Children with a normative need for orthodontic treatment, based on examiner AC did not have a worse oral health-related quality of life. CONCLUSION(S): The CPQ and IOTN AC measure different attributes. There should be a shift towards using quality of life measures to supplement the IOTN in assessing the perceived need for orthodontic treatment.  相似文献   
999.
1000.
Purpose: This study evaluated the effect of two home bleaching regimens (1 h/day versus 7 h/day for a total of 21 days) on the microhardness of superficial enamel treated with 10% carbamide peroxide gel.
Materials and Methods: Rectangular enamel specimens (2.5 × 2.5 × 1 mm) were obtained from human third molars and mounted on the palatal aspect of removable orthodontic retainers. Nine enamel specimens were mounted in each of 10 retainers, used by 10 volunteers during the active phase of the study. Modified 0.089 cm thick bleaching trays were fabricated for each participant. Each bleaching tray fit a participant's arch and the retainer containing the enamel specimens. Enamel specimens were treated with a 10% carbamide peroxide bleaching gel (Nite White® Excel 2Z, Discus Dental, Culver City, CA, USA) for either 1 h/day ( n = 30) or 7 h/day ( n = 30), both for 21 days. Three enamel specimens in each retainer were never treated and served as controls. The retainers were worn by the participants whether or not they underwent bleaching. This simulated the natural action of the saliva/oral fluids on the enamel specimens. Enamel specimens were subjected to pre- and post-treatment microhardness measurements. Post-treatment Knoop hardness numbers were compared with baseline values and analyzed statistically.
Results: Bleaching treatment resulted in a nonsignificant reduction in microhardness values when compared with values of the control nontreated specimens (1.7% and 2.5% reduction in hardness for 1 h/day and 7 h/day, respectively). There was no difference in microhardness between the different treatment regimens.
Conclusion: Home bleaching with 10% carbamide peroxide for up to 7 h/day for 21 days does not significantly affect enamel microhardness.
CLINICAL SIGNIFICANCE
Bleaching with 10% carbamide peroxide for 1 h/day or 7 h/day for a total of 21 days is safe for human enamel.  相似文献   
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