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991.
We report the case of a woman of 34 years who had ulcerative colitis and atypical pyoderma gangrenosum. The pyoderma gangrenosum responded to conservative treatment.  相似文献   
992.
INTRODUCTION: Periodontitis is a common infectious disease to which Porphyromonas gingivalis has been closely linked, in which the attachment tissues of the teeth and their alveolar bone housing are destroyed. We conducted a study to determine if immunization using a purified antigen could alter the onset and progression of the disease. METHODS: Using the ligature-induced model of periodontitis in Macaca fascicularis, we immunized five animals with cysteine protease purified from P. gingivalis and used an additional five animals as controls. Alveolar bone loss was measured by digital subtraction radiography. RESULTS: Immunization induced high titers of specific immunoglobuin G serum antibodies that were opsonic. Total bacterial load, levels of P. gingivalis in subgingival plaque and levels of prostaglandin E(2) in gingival crevicular fluid were significantly reduced. Onset and progression of alveolar bone loss was inhibited by approximately 50%. No manifestations of toxicity were observed. CONCLUSIONS: Immunization using a purified protein antigen from P. gingivalis inhibits alveolar bone destruction in a ligature-induced periodontitis model in M. fascicularis.  相似文献   
993.
Rationally designed beta-sheet-forming peptides that spontaneously form three-dimensional fibrillar scaffolds in response to specific environmental triggers may potentially be used in skeletal tissue engineering, including the treatment/prevention of dental caries, via bioactive surface groups. We hypothesized that infiltration of caries lesions with monomeric low-viscosity peptide solutions would be followed by in situ polymerization triggered by conditions of pH and ionic strength, providing a biomimetic scaffold capable of hydroxyapatite nucleation, promoting repair. Our aim was to determine the effect of an anionic peptide applied to caries-like lesions in human dental enamel under simulated intra-oral conditions of pH cycling. Peptide treatment significantly increased net mineral gain by the lesions, due to both increased remineralization and inhibition of demineralization over a five-day period. The assembled peptide was also capable of inducing hydroxyapatite nucleation de novo. The results suggest that self-assembling peptides may be useful in the modulation of mineral behavior during in situ dental tissue engineering.  相似文献   
994.
Microbial control of the root canal system is one of the key objectives of root canal therapy. Triclosan is a widely accepted broad spectrum antimicrobial agent proven to be effective against many gram-positive and gram-negative bacteria. Triclosan acts by blocking bacterial fatty acid biosynthesis. The addition of Gantrez copolymer has been shown to enhance the antimicrobial activity of triclosan. The purpose of this study was to determine the minimum inhibitory and bactericidal concentrations of triclosan and triclosan with Gantrez against Prevotella intermedia, Fusobacterium nucleatum, Actinomyces naeslundii, Porphyromonas gingivalis, and Enterococcus faecalis. The minimum inhibitory concentration (MIC) of both test solutions was determined for each of the 5 microorganisms by using microtiter serial dilutions. Samples were streaked on 5% sheep blood agar plates and placed in an anaerobic incubator to determine the minimum bactericidal concentration (MBC). The MBC of triclosan ranged from 12-94 microg/mL. The MBC of triclosan with Gantrez ranged from <0.3-10.4 microg/mL. The addition of Gantrez enhanced the bactericidal activity of triclosan. Both triclosan and triclosan with Gantrez demonstrated bactericidal activity against the 5 specific endodontic pathogens.  相似文献   
995.
Abstract: Aim: The aim of this study was to assess the reliability and validate a customized image analysis system, designed for use within clinical trials of general dental hygiene and whitening products, for the measurement of stain levels on extracted teeth and to compare it with reflectance spectrophotometry. Method: Twenty non‐carious extracted teeth were soaked in an artificial saliva, brushed for 1 min using an electric toothbrush and a standard toothpaste, bleached using a 5.3% hydrogen peroxide solution and cycled for 6 h daily through a tea solution. CIE L* values were obtained after each treatment step using the customized image analysis system and a reflectance spectrophotometer. A statistical analysis was carried out in SPSS. Results: Fleiss’ coefficient of reliability for intra‐operator repeatability of the image analysis system and spectrophotometry was 0.996 and 0.946 respectively. CIE L* values were consistently higher using the image analysis compared with spectrophotometry, and t‐tests for each treatment step showed significant differences (P < 0.05) for the two methods. Limits of agreement between the methods were ?27.95 to +2.07, with a 95% confidence of the difference calculated as ?14.26 to ?11.84. The combined results for all treatment steps showed a significant difference between the methods for the CIE L* values (P < 0.05). Conclusion: The image analysis system has proven to be a reliable method for assessment of changes in stain level on extracted teeth. The method has been validated against reflectance spectrophotometry. This method may be used for pilot in vitro studies/trials of oral hygiene and whitening products, before expensive in vivo tests are carried out.  相似文献   
996.
997.
This report describes the case of a 13-year-old Indian boy with popliteal pterygium syndrome. The popliteal pterygium syndrome is an extremely rare hereditary disorder thought to occur with an incidence of approximately 1 in 300000 live births. It is a congenital malformation syndrome affecting the face, limbs, and genitalia with highly characteristic features, including popliteal webbing, cleft palate (with or without cleft lip), lower lip pits, syndactyly, and genital and nail anomalies. This patient was referred to our department because of complaints of pain in the mouth and poor oral health. The orofacial findings included cleft lip, cleft palate, lower lip pits, a few missing teeth, and severely decayed teeth. In this syndrome, the orodental problems are overshadowed by the major syndromic manifestations but nevertheless need appropriate management. These patients have special dental needs and early diagnosis of the affected children is therefore important in order to initiate preventive dental care and carry out appropriate dental treatment at the optimal time.  相似文献   
998.
Health literacy-related problems can interfere with effective doctor-patient communication and effective patient care. This study examined several health literacy-related markers for patients seeking treatment in hospital emergency departments and physician and dentist offices for dental problems and injuries. Participants consisted of low-income white, black, and Hispanic adults who had experienced a dental problem or injury during the previous twelve months and who visited a hospital emergency department, physician, or dentist for treatment. A stratified random sample of Maryland households participated in a cross- sectional telephone survey. Interviews were completed with 94.8 percent of 423 eligible individuals. Multivariable logistic regression analyses were performed. Only 10.0 percent of the respondents expressed a difficulty understanding what they were told by the health provider, while 4.9 percent expressed a difficulty understanding the dental or medical forms they were asked to complete and 6.9 percent reported that they had difficulty getting the health provider to understand their dental problem or injury. Logistic regression analysis found that males and Hispanics were significantly (p<0.05) more likely to experience health literacy-related problems. In general, respondents did not express health literacy-related problems. Additional research is needed to identify health literacy-related barriers to effective patient-provider communication.  相似文献   
999.
Quantitative defects of the enamel are considered risk factors for caries development at the cavitated level. Since caries risk assessment and control should be implemented as early as possible in order to prevent operative treatment, it seemed interesting to investigate the relationship between enamel defects and caries development in the stages of progression that precede cavitation. The impact of enamel defects and selected child-mother indicators on early caries development was investigated in a cohort of Brazilian preschool children. The null hypothesis that developmental defects of the enamel and dental caries are independent and that an association between them occurs by chance was tested. The sample (n = 1,718) was made up of 2- to 5-year-olds. Developmental defects of enamel and caries on buccal surfaces were identified in 48 and 26% of the children, respectively. Bivariate analyses at the surface level showed neither an association between demarcated/diffuse opacity and caries experience (p ≥ 0.64, GLM), nor between the presence of hypoplastic surfaces and non-cavitated lesions (p = 0.29, GLM). The multivariate analyses indicated that in the mouths of individual children, hypoplastic surfaces were more likely to present filled surfaces and non-cavitated/cavitated lesions than non-hypoplastic surfaces (within-child p = 0.03, GEE). However, children having teeth with hypoplastic surfaces were not at higher caries risk than those children who did not present hypoplastic surfaces (between-child p = 0.23, GEE). The null hypothesis could not be accepted for quantitative defects such as hypoplasia, since they had a significant impact on the within-child prevalence of filled surfaces and non-cavitated/cavitated lesions.  相似文献   
1000.
To cite this article:
Int J Dent Hygiene 9 , 2011; 223–228
DOI: 10.1111/j.1601‐5037.2010.00480.x
Bellamy PG, Prendergast M, Strand R, Yu Z, Day TN, Barker ML, Mussett AJ. Can anti‐erosion dentifrices also provide effective plaque control? Abstract: Objective: While gingivitis and caries continue to be prevalent issues, there is growing concern about dental erosion induced by dietary acids. An oral hygiene product that protects against all these conditions would be beneficial. This study investigated the potential of two anti‐erosion dentifrices to inhibit plaque. Methods: This was a randomized, three‐period, two‐treatment, double‐blind, crossover study evaluating a stannous chloride/sodium fluoride dentifrice (SnCl2/NaF, blend‐a‐med® Pro Expert) and a popular anti‐erosion dentifrice (NaF, Sensodyne® ProNamel?). During Period 3, subjects were randomized to repeat one treatment to evaluate any product carryover effects. Each treatment period was 17 days. Test dentifrices were used with a standard manual toothbrush. Digital plaque image analysis (DPIA) was employed at the end of each period to evaluate plaque levels (i) overnight (am prebrush); (ii) post‐brushing with the test product (am post‐brush); and (iii) mid‐afternoon (pm ). Analysis was conducted via an objective computer algorithm, which calculated total area of visible plaque. Results: Twenty‐seven subjects completed the study. At all time points, subjects had statistically significantly (P ≤ 0.0001) lower plaque levels after using the SnCl2/NaF dentifrice than the NaF dentifrice. The antiplaque benefit for the SnCl2/NaF dentifrice versus the NaF dentifrice was: am prebrush = 26.0%; am post‐brushing = 27.9%; pm = 25.7%. Conclusions: The SnCl2/NaF dentifrice provided significantly greater daytime and overnight plaque inhibition than the NaF toothpaste. When recommending dentifrice to patients susceptible to dental erosion, clinicians can consider one that also inhibits plaque.  相似文献   
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