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521.
522.

Objectives

The aims of this study were to find and compare the effect of directional (DIR) processing of two different hearing aids via both subjective and objective methods, to determine the association between the results of the subjective and objective evaluations, and to find out individual predictive factors influencing the DIR benefit.

Methods

Twenty-six hearing aid users fitted unilaterally with each two different experimental hearing aid performed modified Korean Hearing in Noise Test (K-HINT) in three DIR conditions; omnidirectional (OMNI) mode, OMNI plus noise reduction feature, fixed DIR mode. In order to determine benefits from DIR benefit within a hearing aid and compare performance of the DIR processing between hearing aids, a subjective questionnaire was administrated on speech quality (SQ) and discomfort in noise (DN) domain. Correlation analysis of factors influencing DIR benefit was accomplished.

Results

Benefits from switching OMNI mode to DIR mode within both hearing aids in K-HINT were about 2.8 (standard deviation, 3.5) and 2.1 dB SNR (signal to ratio; SD, 2.5), but significant difference in K-HINT results between OMNI and OMNI plus noise reduction algorithm was not shown. The subjective evaluation resulted in the better SQ and DN scores in DIR mode than those in OMNI mode. However, the difference of scores on both SQ and DN between the two hearing aids with DIR mode was not statistically significant. Any individual factors did not significantly affect subjective and objective DIR benefits.

Conclusion

DIR benefit was found not only in the objective measurement performed in the laboratory but also in the subjective questionnaires, but the subjective results was failed to have significant correlation with the DIR benefit obtained in the K-HINT. Factors influencing individual variation in perceptual DIR benefit were still hard to explain.  相似文献   
523.
Background/aims The possibility of proximal lesion without distal polyps is a weak point of sigmoidoscopic colon cancer screening, but the clinical significance of distal findings for advanced proximal neoplasm (APN) is uncertain. The aim of this study was to assess the significance of a distal finding as a predictor of APN. Materials and methods Asymptomatic patients ≥50 years old were enrolled from among patients who underwent polypectomy at 11 tertiary medical centers during the Korean Association for the Study of Intestinal Disease prospective study conducted between July 2003 and March 2004. Polyps located distal to the splenic flexure were defined as distal polyps. An advanced neoplasm was defined as a polyp of ≥10 mm in size, and/or with villous features, and/or with high-grade dysplasia, or invasive cancer. Age, gender, and distal polyp size, appearance, and histology were analyzed as risk factors of APN. The sensitivity and positive predictive value of distal polyps for APN were calculated. Results Data from 826 patients were analyzed. Mean patient age was 60.1 years (range 50–86), and 71.3% were men. APN was found in 98 patients, and 45 (45.9%) patients had no distal polyps. Risk factors of APN were a male gender, distal polyp size, and an advanced distal neoplasm. Sensitivities of a distal polyp of ≥10 mm and of an advanced distal neoplasm for APN were both 38.8% with positive predictive values of 13.3 and 14.4%, respectively. Conclusions Although distal colon findings were found to be helpful for predicting APN in asymptomatic patients aged ≥50 years, APN without distal polyps requires careful consideration.  相似文献   
524.
It is well known that ingestion of low concentrations of hydrogen peroxide is usually nontoxic; this does not produce gas embolism and is only a mild irritant to the gastrointestinal tract. We report the case of a 25-year-old woman who ingested one mouthful of 3% hydrogen peroxide and presented to the Emergency Department with persistent vomiting and epigastric pain. The radiographic evaluation found portal venous gas emboli. In addition, upper gastrointestinal endoscopy performed 2 h after ingestion revealed diffuse hemorrhagic gastritis. She showed a decrease of hemoglobin concentration and a positive test result for occult blood in stool. She was observed for 14 days and discharged. Follow-up endoscopy showed erythematous gastritis. This case illustrates that a low concentration of hydrogen peroxide can cause portal venous gas embolism and severe gastrointestinal injuries even if only a small amount is ingested.  相似文献   
525.
526.

Background

The glycemic index (GI) is a measure of the ability of a food to raise glucose levels after it is eaten. Continuous glucose monitoring (CGM) has been shown to give identical values of GI when compared to traditional methods. However, there has been no standardized protocol for measuring GI that takes into account interindividual variability and chronophysiological glycemic response to food. Our aim was (1) to create and describe software based on a Microsoft Excel 2000 spreadsheet to facilitate rapid, automated, accurate, and standardized processing of data obtained using recent CGM methodology to measure GI and its variability and (2) to assess the benefits of this new approach.

Method

Twenty healthy subjects consumed 50 grams of glucose or four alternative foodstuffs (chocolate, apple baby food, rice squares, or yogurt) at breakfast and dinner during 1 week, resulting in 300 CGMS glucose profiles; 92% of meal tests were satisfactory for evaluation. Application and functions of the software DegifXL are described.

Results

Using the new spreadsheet software DegifXL, time required for data processing for the 15 data sets for each subject was reduced from 2000 to 160 minutes relative to previously used manual methods. We characterized the GI for four foodstuffs with three replicate measurements in each of 20 subjects and evaluated between person, between time period, and between replicate GI variabilities.

Conclusion

DegifXL, combined with CGM, was an efficient and effective tool for routine measurement of group- and subject-related GI.  相似文献   
527.
AIMS: Lung dysfunction occurring in chronic heart failure worsens clinical status and exercise performance. The prognostic value of airway and alveolar function measurements in chronic heart failure has not been explored. We aimed to evaluate the prognostic value of lung function tests in a population of patients with stable chronic heart failure. METHODS AND RESULTS: One hundred and six stable chronic heart failure patients (whose left ventricular ejection fraction averaged 33 +/- 1%) underwent echocardiography, metabolic stress testing, assessment of pulmonary function at rest (by spirometry), of alveolar diffusing capacity (DLco) (with carbon monoxide technique) and of its membrane (DM) and capillary blood volume (Vc) components. Prognostic relevance of pulmonary variables was assessed by the Kaplan-Meier approach with log-rank testing and by Cox regression analysis. Cut-off values of lung parameters were based on the 33rd and 66th centiles. Seventeen patients died for cardiac reasons. Non-survivors compared to survivors showed lower forced expiratory volume in 1 s (2 X 1 +/- 0 X 1 vs 2 X 4 +/- 0 X 1 l; P<0 X 01), forced vital capacity (2 X 6 +/- 0 X 1 vs 2 X 9 +/- 0 X 1 l; P<0 X 01), maximal voluntary ventilation (80 X 7 +/- 2 X 5 vs 95 X 4 +/- 2 X 7 l; P<0 X 01), DLco (16 X 5 +/- 1 X 1 vs 19 X 3 +/- 0 X 6 ml . min(-1) . mmHg(-1); P<0 X 01) and DM (25 X 1 +/- 1 X 8 vs 31 X 9 +/- 1 X 5 ml . min(-1) . mmHg(-1); P<0 X 01). They also exhibited a smaller peak VO2 (14 X 6 +/- 0 X 7 vs 15 X 9 +/- 0 X 6 ml . min(-1) . kg(-1); P<0 X 05) and a steeper VE/VCO2 slope (45 X 0 +/- 1 X 7 vs 41 X 9 +/- 1 X 5; P<0 X 01). Multivariate analysis revealed that DM was the only independent predictor of cardiac death. Cases at high risk for adverse outcome were identified by a DM<24 X 7 ml . min(-1) . mmHg(-1). Patients receiving ACE-inhibitors presented with a higher DM (32 X 1 +/- 1 X 7 vs 27 X 9 +/- 1 X 7 ml . min(-1) . mmHg(-1), P<0 X 05) as well as a better Cox estimated survival rate. CONCLUSIONS: Impaired DM is a powerful independent predictor of worse prognosis in stable chronic heart failure and may be considered an additional index of disease severity, as well as a specific therapeutic target.  相似文献   
528.
IJ Choi 《Clinical endoscopy》2012,45(3):217-219
Upper gastrointestinal (GI) endoscopy is the most basic part of endoscopy field. Although old and basic procedures are still in use, a line of innovative techniques and devices are being introduced to allow much complex and difficult procedures in endoscopy unit. High quality upper endoscopic procedures can replace or obviate surgical treatment. Selected reviews dealing with non-variceal upper GI bleeding, challenging esophageal stenting, endoscopic management of subpeithelial tumor, and endoscopic evaluation for candidate lesions of endoscopic submucosal dissection were selected among the topics from International Digestive Endoscopy Network 2012.  相似文献   
529.
The purpose of this study was to assess the characteristics and predictors of subclinical coronary atherosclerosis in young adults. The study also evaluated predictors of cardiac events. We retrospectively enrolled 914 self-referred asymptomatic subjects under the age of 45 (552 men, 362 women) who had undergone both coronary CT angiography (CCTA) and coronary artery calcium scoring. Two radiologists analyzed plaque composition and degree of stenosis. For all subjects, we evaluated clinical risk factors and investigated cardiac events. Subclinical coronary atherosclerosis was found in 86 subjects (9.4 %). Among them, 64 subjects (74.4 %) had a single coronary artery plaque. On analysis of individual segments, the most common type of plaque was non-calcified plaque (NCP) (58 %), which was found in 63 subjects (6.9 %). Significant coronary artery stenosis was found in 9 subjects (0.1 %). Predictors of subclinical coronary atherosclerosis were age, male gender, hypertension, and diabetes mellitus. Male gender, diabetes mellitus, and amount of smoking were independent predictors of NCP. High low density lipoprotein cholesterol and calcium scores were also significant predictors of stenosis. Myocardial infarction developed in 1 subject, unstable angina in 2, stable angina in 1, and death in 1 (2.45 cardiac events per 1,000 person-years of follow-up). Multivariate analysis revealed hazard ratios of 2.2 for subclinical coronary atherosclerosis, 49.17 for NCP, and 105.58 for significant stenosis. The prevalence of subclinical coronary atherosclerosis in asymptomatic young adults is not negligible. CCTA has the potential to enhance risk stratification and prediction for coronary artery disease in asymptomatic young adults.  相似文献   
530.
This study was performed to investigate the prevalence of rectal colonization with multidrug-resistant Escherichia coli in dogs hospitalized at veterinary hospitals in Korea and to assess the molecular epidemiologic traits of this organism. A total of 63 unique E. coli isolates obtained from the rectal swabs of hospitalized dogs were analyzed. Genes encoding CTX-M extended-spectrum β-lactamases (ESBLs) and AmpC enzymes were detected in 21 (33.3%) and 15 (23.8%) canine E. coli isolates, respectively. Twelve canine E. coli isolates harbored both the genes encoding the CTX-M and AmpC enzymes. Six ESBL-producing E. coli isolates also carried the rmtB gene. All 24 E. coli isolates producing CTX-M ESBL and/or CMY-2 were resistant to ciprofloxacin. Furthermore, mutations were found in the gyrA and the parC genes. In most cases, the bla genes of the CTX-M ESBL and AmpC enzymes and the rmtB gene were localized to incompatibility group F (IncF) plasmids. Possible small clonal outbreaks are suggested because some E. coli isolates recovered in the same veterinary hospital were identified as identical sequence types and showed identical banding patterns in repetitive sequence-based polymerase chain reaction. The horizontal transfer of IncF plasmids and the clonal transfer of E. coli strains are suggested to play a role in the dissemination of antimicrobial resistance genes, and this transfer may occur across host species (i.e., between humans and dogs).  相似文献   
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