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991.
Anti-cardiolipin antibodies in sera from patients with periodontitis   总被引:2,自引:0,他引:2  
Antiphospholipid antibodies are commonly found in patients with systemic lupus erythematosus or the antiphospholipid syndrome, and a subset of such antibodies is associated with prothrombotic events such as stroke and with adverse pregnancy outcomes and fetal loss. We examined sera from 411 patients who were clinically characterized as to their periodontal disease status for serum levels of beta2-glycoprotein I-dependent anti-cardiolipin autoantibodies (anti-CL). The prevalence of patients with chronic periodontitis (CP) and generalized aggressive periodontitis (GAgP) positive for anti-CL (16.2% and 19.3%, respectively) was greater than that in healthy controls (NP) and localized aggressive periodontitis (LAgP) patients (6.8% and 3.2%). Patients with these autoantibodies demonstrated increased pocket depth and attachment loss compared with patients lacking the antibodies. Analysis of the data indicates that patients with generalized periodontitis have elevated levels of autoantibodies reactive with phospholipids. These antibodies could be involved in elevated risk for stroke, atherosclerosis, or pre-term birth in periodontitis patients.  相似文献   
992.
Historically, shade change assessment associated with vital bleaching treatment regimens has been visually evaluated through the use of shade guide tabs. Innovations in the industry of dentistry have brought forth new technologies capable of measuring such changes via the capture and analysis of reflected wavelengths of light. CLINICAL SIGNIFICANCE: This article introduces the use of a 45/0 reflectance spectrophotometer and identifies the advantages and limitations associated with such a technology in the assessment of shade change owing to vital bleaching.  相似文献   
993.
A dentist referred a 35-year-old woman to the department of oral and maxillofacial surgery because of recurrent aphtous-like changes of the oral mucosa and persisting pain. She also experienced similar complaints about her eyes and genitals. This combination of symptoms was suspect for Beh?et's disease.  相似文献   
994.
995.
The epidemiology of HIV-related oral disease in industrialized nations has evolved following the initial manifestations described in 1982. Studies from both the Americas and Europe report a decreased frequency of HIV-related oral manifestations of 10-50% following the introduction of HAART (highly active antiretroviral therapy). Evidence suggests that HAART plays an important role in controlling the occurrence of oral candidosis. The effect of HAART on reducing the incidence of oral lesions, other than oral candidosis, does not appear as significant, possibly as a result of low lesion prevalence in industrialized countries. In contrast to other oral manifestations of HIV, an increased prevalence of oral warts in patients on HAART has been reported from the USA and the UK. HIV-related salivary gland disease may show a trend of rising prevalence in the USA and Europe. The re-emergence of HIV-related oral disease may be indicative of failing therapy. A range of orofacial iatrogenic consequences of HAART has been reported, and it is often difficult to distinguish between true HIV-related oral disease manifestations and the adverse effects of HAART. A possible association between an increased risk of oral squamous cell carcinoma and HIV infection has been suggested by at least three epidemiological studies, with reference to the lip and tongue. These substantial and intensive research efforts directed toward enhancing knowledge regarding the orofacial consequences of HIV infection in the industrialized nations require dissemination in the wider health care environment.  相似文献   
996.
997.
This study determined the influence of dentine structure on the micro-tensile bond strengths between resin and dentine of two different dentine adhesive systems (Single Bond, 3M Dental Products, St Paul, MN; MF-102 (experimental self-etching primer), GC Corporation, Tokyo, Japan). The study was separated into two main parts: bond strength measurement and investigation of the bonding interface. Twenty-two human premolars were used for the bond strength measurement. Each tooth was cut vertically, separating the tooth into mesio-distal halves. One half of the tooth was used to bond to a surface perpendicular to the dentinal tubules and other half to bond to a surface parallel to the tubules. For each half, six locations of dentine were bonded. Each material was used in accordance to the manufacturer's directions. Cylindrical hourglass-shaped specimens of 1.2 mm diameter at the bonded interface were manufactured. The bonds were stressed in tension at a crosshead speed of 1 mm/min. Mean bond strengths were compared using LSD, one-way ANOVA, and Student's t-test. The fractured surfaces were examined under a scanning electron microscope, and the frequency of fracture modes was compared using the Kruskal-Wallis and Mann-Whitney U tests. For the investigation of the bonded interface, four teeth were prepared by the same procedure used for the bond test specimens. The bonded interfaces were observed after an acid-base treatment or fracturing across the bonded interface, prior to investigation with a field-emission scanning electron microscope. For Single Bond, the bond strengths for mid-root dentine were significantly lower than for other locations (p < 0.05). For MF-102, there was no significant difference for all locations (p > 0.05). MF-102 bonded well to all locations of dentine while Single Bond showed a porous zone at the base of the hybrid layer. The bonds were not influenced by tubule orientation. The results indicate that the bond for Single Bond may be affected by its ability to penetrate demineralised dentine in different locations of a tooth. The self-etching primer of MF-102 produces a good bond and is independent of the position on the tooth.  相似文献   
998.
OBJECTIVE: This study presents race/ethnic-specific distributions of dental expenditures and their sources of payment by socioeconomic characteristics among US working-age adults. METHODS: Data for persons aged 19-64 years from the 1987 National Medical Expenditure Survey (NMES) (n = 18,696) were used to calculate mean dental expenditures and their 95 percent confidence intervals. RESULTS: Dental expenditures were reported by 44.5 percent of participants. Non-Hispanic whites and persons with higher income were more likely to report dental expenditures than their counterparts. Among persons reporting expenditures, those with lower income had lower expenditures than higher-income persons. No differences in the amount of expenditures by race/ethnicity, sex, or employment status were observed. In all race/ethnic groups almost half the expenditures were paid out-of-pocket and one-third by dental insurance. CONCLUSION: While sociodemographic characteristics determined who had dental expenditures, they did not determine the amount or source of those expenditures.  相似文献   
999.
Abstract. The aim of this cross-sectional study was to investigate the clinical application of chairside tests for gingival crevicular fluid (GCF) aspartale amino-transferase (AST) levels and plaque BANA hydrolysis activity with the presence of the periodontal pathogens Porphyromonas gingivalis and Actinohacillus action-mycetemcomitans. The study comprised 100 periodontitis sites (pocket depths≥4 mm. GI = 3) from 10 patients with chronic adult periodontitis and 100 control sites (pocket depths <4 mm. GI<3) from 10 periodontally healthy patients comprising 55 healthy sites (pocket depths <4 mm. GI=0) and 45 gingivitis sites (pocket depths <4 mm, GI=1 or 2). The values for both BANA hydrolysis and AST levels were significantly higher in samples from periodontitis compared with gingivitis and healthy sites (p<0.001), A. actinomycetemcomitans was identified in 45% and P. gingivalis in 17% of periodontitis sites but neither pathogen was recovered from control sites and there was no significant correlation with (he clinical parameters measured. There was no significant relationship between the presence of P. gingivalis and/or A. actinmycetemcomitans with BANA hydrolysis or AST levels. A significant correlation (p=0.0017) was observed between BANA hydrolysis and pocket depth and between AST hydrolysis and the GI (p=0.01). This study failed to demonstrate a positive association between chairside analysis of GCF metabolites for AST levels and/or BANA hydrolysis with P. gingivalis and A. actinomycetemcomitans. However, the GCF metabolites had a significant correlation with periodontally diseased sites in patients with chronic adult periodontitis and may help confirm clinical observations.  相似文献   
1000.
The purpose of this study was to evaluate the concept that novice clinicians could perform clinical endodontics better and more efficiently if the stainless steel hand file technique is replaced with a nickel titanium rotary file technique. In phase 1 of the study, every endodontic case performed by 2 groups was evaluated for total treatment time. In phase 2, the mesial roots of mandibular molars were evaluated for radiographic quality of completed obturation. The authors found that when the rotary file technique was substituted for the hand file technique, appointment time for case completion was significantly decreased (P<.001) and overall radiographic quality of mandibular molar mesial root obturation was significantly increased (P=.0009). These results support the hypothesis that novice clinicians can perform endodontic therapy more efficiently when using a nickel titanium rotary file technique. In addition, no differences were noted in the incidence of file fracture when using rotary instruments.  相似文献   
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