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991.
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Chaussain-Miller C Decup F Domejean-Orliaguet S Gillet D Guigand M Kaleka R Laboux O Lafont J Medioni E Serfaty R Toumelin-Chemla F Tubiana J Lasfargues JJ 《Clinical oral investigations》2003,7(1):32-37
The objective of the present study was to assess the efficiency and benefit of a chemomechanical system for carious dentin removal, Carisolv, in general practice. A revised caries classification, the site/stage concept, was used to describe the clinical situations of all carious lesions treated. The study was performed by 12 investigators, and 120 carious lesions were treated with Carisolv. Sixty percent of the cases were treated without anaesthesia, and we found a significant correlation between chemomechanical treatment without anaesthesia and absence of pain ( P=0.01). In 78.3% of the cases, carious dentin was totally removed with Carisolv, and in 21.7%, the dentin treatment was completed by drilling. In cases performed with Carisolv alone, the time required to remove carious dentin was 11.1+/-9.51 min (mean+/-SD). Treatment time was equivalent for all sites and increased significantly with each successive stage of lesion progression ( P<0.001). In 82.5% of cases, the clinicians were satisfied with Carisolv, and in 99.2%, so were the patients. We conclude that, using clinical examination methods, Carisolv seems to remove carious dentin at all sites and stages of carious lesions but must be made more efficient for use in general practice. 相似文献
995.
PURPOSE: The purpose of this study was to explore the association between asthma and periodontal disease in adolescents using oral examination and health interview data from the Third National Health and Nutrition Examination Survey (NHANES III) 1988-1994. METHODS: The study population comprised 1,596 adolescents 13 to 17 years of age: 253 (16%) asthmatics and 1,358 (84%) nonasthmatic controls who were examined for bleeding on probing (BOP), subgingival calculus (SBC), supragingival calculus (SPC), probing depth greater than or equal to 3 mm (PD), and loss of periodontal attachment greater than or equal to 2 mm (LPA). The authors fitted separate multivariate GEE Poisson regression models adjusting for parents' income, gender, race, exposure to potentially xerogenic drugs (antihistamines, corticosteroids, and inhalers), tobacco exposure, and dental examination within the past year. RESULTS: None of the periodontal measures was associated with asthma severity or with the use of antiasthmatic drugs. However, several covariates had statistically significant odds ratios (P < .05). CONCLUSIONS: There was no evidence to support the association between asthma and periodontal health in the adolescent population. Since the findings may be due to the inherent limitations of cross-sectional studies, the lack of knowledge about the daily dose of antiasthmatic medication, and the level of-compliance with the therapeutic regimen, future studies should be longitudinal and monitor medication use. 相似文献
996.
OBJECTIVE: The purpose of this study was to investigate the suitability of different synthetic calcium phosphate based substrates as a biomimetic enamel surface model for orthodontic bond strength testing. METHODS: Carbonated apatite, amorphous calcium phosphate and commercial hydroxyapatite specimens were prepared as substrates for orthodontic bond strength testing. Carbonated apatite specimens were prepared by pressing, sintering and treatment with NaF. The shear bond strength was measured with a universal testing machine. RESULTS: Hydroxyapatite, amorphous and cold pressed carbonated hydroxyapatite exhibited fractures within the substrate after debonding. Mean bond strength values for carbonated hydroxyapatite were 7.38 (1.75) MPa for specimens pressed at 300 degrees C and 9.55 (2.23) MPa for specimens pressed at 300 degrees C and then sintered at 600 degrees C. An additional NaF treatment after sintering resulted in lower bond strength measurements of on average 6.52 (1.03) MPa. SIGNIFICANCE: Hot pressed and sintered carbonated hydroxyapatite showed acceptable shear bond strength values and may represent a suitable biomimetic model for orthodontic bond strength testing. 相似文献
997.
Calcium hydroxide is advocated as an intracanal medication for various purposes, including prevention of posttreatment symptoms. This study assessed whether calcium hydroxide had a pain-controlling effect at different times when compared with no intracanal medication. One hundred forty patients participated. Conditions diagnosed were pulp/periapical pathosis with or without symptoms. At least partial cleaning and shaping was completed. At random, either Ca(OH)2 plus H2O paste or a dry cotton pellet was placed in the canals of half the teeth, respectively. All teeth were temporized with Intermediate Restorative Material. Patients assessed posttreatment pain up to 48 h as none, mild, moderate, or severe. The pain levels in each test group [Ca(OH)2 versus cotton pellet] at each time period were compared statistically with a multiple-regression analysis. There was no significant difference in posttreatment pain between the two groups at any time period or with any diagnosis or symptom. The use of calcium hydroxide as an intracanal medication was unrelated to the incidence and/or severity of posttreatment pain. 相似文献
998.
Clark DB 《Journal (Canadian Dental Association)》2003,69(1):20-24
Chronic mental illness and its treatment carry inherent risks for significant oral diseases. Given the shift in treatment regimens from the traditional institutionally based approach to more community-focused alternatives, general dental practitioners can expect to see and be asked to treat patients with various forms of psychiatric disorders. One such group consists of patients with bipolar disorder (including type I bipolar disorder or manic-depressive disorder). The purpose of this paper is to acquaint the dental practitioner with the psychopathological features of bipolar disorder and to highlight the oral health findings and dental management considerations for these patients. Bipolar disorder is considered one of the most treatable forms of psychiatric illness once it has been diagnosed correctly. Through a combination of pharmacotherapy, psychotherapy and life-adjustment skills counselling, these patients are better able to understand and cope with the underlying mood swings that typify the condition and in turn to interact more positively and progressively within society as a whole. Both the disease itself and its various pharmacologic management modalities exact a range of oral complications and side effects, with caries, periodontal disease and xerostomia being encountered most frequently. It is hoped that after reading this article the general dental practitioner will feel more confident about providing dental care for patients with bipolar disorder and in turn to become a vital participant in the reintegration of these patients into society. 相似文献
999.
Bhaskaran V Qualtrough AJ Rushton VE Worthington HV Horner K 《International endodontic journal》2005,38(9):645-652
AIM: To measure and compare the relationships between image quality and X-ray exposure for three types of intraoral imaging system (conventional film, phosphor plate system and CCD-based system). METHODOLOGY: Kodak 'Insight' F-speed film, Digora FMX (phosphor plate system) and Visualix USB (CCD system) were used to produce series of radiographic images of two tooth-bearing jaw specimens (maxillary molar and mandibular molar regions) at a range of X-ray exposures from 10 ms to 2000 ms (all at 6 mA and 60 kV). Digital images were viewed from a computer monitor and films viewed on a conventional light box. Five observers scored each image using a five-point subjective image quality scale (0-4). RESULTS: Optimum image quality (4) was seen for conventional film. Neither digital system achieved this score at any exposure, achieving in both cases a maximum mean score of 3.1 (adequate visualization). The two digital systems, however, provided adequate visualization at substantially lower exposure times. Dose reduction over conventional film for maximum quality images with Visualix USB was 20%, but for Digora FMX it was 70%. All three systems gave acceptable (quality score of two or higher) images over a broad range of exposures. CONCLUSIONS: In terms of subjective image quality, F-speed film performed better than the two digital systems, but this must be weighed against the ability of the two digital systems to give adequate image quality at lower radiation doses. 相似文献
1000.
This study investigated the use of various light-curing regimens with standardized light energy density on the effectiveness of cure of a visible light activated resin composite (Z100, 3M-ESPE). A light-cure unit (Variable Intensity Polymerizer (VIP), BISCO Inc) which permitted individual control over time and intensity, was used. The five light-curing modes investigated include Pulse Delay (PD), Pulse Cure (PC), Soft-start (SS), Turbo (T) and Control (C). Effectiveness of cure was established by measuring the top and bottom Knoop hardness of 2-mm thick composite specimens using a digital microhardness tester (n=5, load=500g; dwell time=15 seconds) immediately and at one-day post-polymerization. Data obtained was analyzed using one-way ANOVA/Scheffe's post hoc test and Independent Samples t-tests (p<0.05). Top KHN observed immediately after polymerization with C was significantly lower than PD. At one day post-polymerization, the top KHN obtained with C was significantly lower than PD, SS and T. No significant difference in bottom KHN was observed among the different curing modes immediately after curing. At one day post-polymerization, the bottom KHN obtained with C was significantly lower than SS and T. Regardless of curing regimens, top and bottom values at one day were significantly higher than those observed immediately after light polymerization. No significant difference in mean hardness ratio was observed among the different curing regimens immediately and one day later. Effectiveness of the cure at the bottom surfaces of composites may be increased by soft-start and turbo polymerization regimens. 相似文献