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991.
Obtaining a prehospital 12-lead electrocardiogram (ECG) diagnostic of acute myocardial injury has been demonstrated to hasten the administration of thrombolytic agents in the emergency department. This case demonstrates that a prehospital electrocardiogram diagnostic of acute anterior wall infarction can become non-diagnostic following routine administration of oxygen, nitroglycerin, and morphine by paramedics. Although this phenomenon has been observed in the in-hospital setting, it has not been reported in patients with a prehospital ECG.  相似文献   
992.
BACKGROUND: Body composition in children is generally measured by 2-component (2C) models, which are subject to error arising from variation in fat-free mass (FFM) composition. The 4-component (4C) model, which divides body weight into fat, water, mineral, and protein, can overcome these limitations. OBJECTIVE: The aims of our study were to 1) describe 4C model data for children aged 8-12 y; 2) evaluate interindividual variability in the hydration, bone mineral content, and density of FFM; 3) evaluate the success with which 2C models and bedside techniques measure body composition in this age group with use of the 4C model as a reference. DESIGN: Dual-energy X-ray absorptiometry, underwater weighing, deuterium dilution, bioelectrical impedance analysis, and anthropometry were used to determine body composition in 30 children. The contribution of methodologic error to the observed variability in the hydration and density of FFM was evaluated by using propagation of error. RESULTS: Mean (+/-SD) FFM density and hydration were 1.0864+/-0.0074 kg/L and 75.3+/-2.2%, respectively, and were significantly different from adult values (P < 0.02). Relative to the 4C model, deuterium dilution and dual-energy X-ray absorptiometry showed no mean bias for fatness, whereas underwater weighing underestimated fatness (P < 0.025). Fatness determined by using skinfold-thickness and bioelectrical impedance analysis measurements along with published equations showed poor agreement with 4C model data. CONCLUSIONS: Biological variability and methodologic error contribute equally to the variability of FFM composition. Our findings have major implications for bedside prediction methods used for children, traditionally developed in relation to underwater weighing.  相似文献   
993.
994.
Development of acute neurological symptoms secondary to cerebral oedema is well described in diabetic ketoacidosis (DKA) and often has a poor prognosis. We present the clinical and radiological data of a 17‐yr‐old girl who developed cortical blindness, progressive encephalopathy, and seizures caused by posterior reversible encephalopathy syndrome (PRES) that developed after her DKA had resolved. Vasogenic oedema in PRES resolves if the underlying trigger is identified and eliminated. In this case, hypertension was identified as the likely precipitating factor and following treatment her vision and neurological symptoms rapidly improved. We suggest how recent DKA may have contributed to the development of PRES in this patient.  相似文献   
995.
Objectives Sources of immunization data include state registries or immunization information systems (IIS), medical records, and surveys. Little is known about the quality of these data sources or the feasibility of using IIS data for research. We assessed the feasibility of collecting immunization information for a national children’s health study by accessing existing IIS data and comparing the completeness of these data against medical record abstractions (MRA) and parent report. Staff time needed to obtain IIS and MRA data was assessed. Methods We administered a questionnaire to state-level IIS representatives to ascertain availability and completeness of their data for research and gather information about data formats. We evaluated quality of data from IIS, medical records, and reports from parents of 119 National Children’s Study participants at three locations. Results IIS data were comparable to MRA data and both were more complete than parental report. Agreement between IIS and MRA data was greater than between parental report and MRA, suggesting IIS and MRA are better sources than parental report. Obtaining IIS data took less staff time than chart review, making IIS data linkage for research a preferred choice. Conclusions IIS survey results indicate data can be obtained by researchers using data linkages. IIS are an accessible and feasible child immunization information source and these registries reduce reliance on parental report or medical record abstraction. Researchers seeking to link IIS data with large multi-site studies should consider acquiring IIS data, but may need strategies to overcome barriers to data completeness and linkage.  相似文献   
996.
Purpose: Many children are requiring tube weaning intervention as a result of increased survival rates of high risk infants and the temporary use of feeding tubes. This study aimed to describe service delivery models and treatment approaches in a variety of paediatric feeding/tube weaning programs.

Method: A questionnaire on tube weaning was formulated based on a literature review. Purposive maximum variation sampling was used to include feeding/ weaning programs operating in a variety of settings and countries. Eight feeding teams in Australia, Europe and the USA agreed to participate and completed the questionnaire.

Result: All teams employed sensori-motor interventions, with the majority also offering psychological interventions. Six of eight teams utilised hunger induction during the initiation of tube weaning, and in many cases this preceded eating skill development or controlled sensory modulation.

Conclusion: A multi-model tube weaning approach is commonly adopted by many centres worldwide. In many cases, psychological theory and theoretical orientation is fundamental to tube weaning practice. Further investigation regarding the efficacy and effectiveness of weaning interventions is recommended to ensure clinical practice is based on sound evidence. This may present as a challenge given many interventions occur concomitantly and the psychotherapeutic experience is difficult to evaluate.  相似文献   

997.
The polymerase chain reaction (PCR) technique has become an important, widely employed method for the detection and quantitation of the nucleic acid sequences used in the diagnosis and monitoring of genetic and infectious diseases. Much attention has been directed at the problem of false-positive PCR results, which are generally attributed to low-level laboratory contamination of amplified sequences ("carryover"). In contrast, few investigators have commented on the somewhat less frequent, but equally problematic, false-negative PCR results. Investigation of the source of sporadic false-negative PCR reactions found that glove powder, inadvertently introduced into tubes when gloves are changed in an effort to reduce false-positive results, can nonspecifically inhibit each of the major steps in the PCR detection process. Methodologic precautions are recommended to minimize this problem.  相似文献   
998.
The purpose of this study was to compare probing measurements obtained using a newly developed constant force electronic probe, which eliminates errors of visual reading and variable force, to those obtained using a standard periodontal probe. The probe was connected to a digital readout through a linear variable differential transformer; the digital readout was connected to a printer and a foot switch. When the probe was in position and the foot switch depressed, the pocket depth was printed to the nearest 0.1 mm. 12 subjects with minimal to early periodontitis were selected for the study. The pocket depths of each patient were recorded electronically utilizing a constant force of 25 g, and conventionally using the same instrument in a "locked" position and visual reading. Probings were performed on each subject by 3 different examiners, on 3 separate occasions 2-3 days apart. The results showed a high correlation between manual and electronic probing. The average correlations for the 3 investigators between examinations were consistently higher for the electronic probings. In comparing the 3 examiners to each other, consistently higher correlations were found for the electronic pocket readings. Correlations for single-rooted teeth were lower for all 3 examiners. The pocket depth measurements recorded when using the manual probe with visual readings were consistently deeper than those obtained using the electronic probe with computer readings. It was concluded that the reproducibility of measurements obtained with the electronic probe was significantly superior to that obtained with a manual probe.  相似文献   
999.
The case history of a woman with a "female adnexal tumor of probable Wolffian origin" is described in which the neoplasm recurred three times during a 16-year interval and responded with prolonged remission after repeated surgical excision and radiotherapy. Ultrastructural data are given to support the Wolffian nature of the tumor. Although the tumor was considered in the past to be a benign neoplasm, the current report, as well as six others in which the tumor recurred or metastasized, indicates that the female adnexal tumor of probable Wolffian origin should be classified within the International Classification of Disease-Oncology and the Systematized Nomenclature of Medicine nomenclatures as "of low malignant potential."  相似文献   
1000.
Graefe's Archive for Clinical and Experimental Ophthalmology - To estimate light exposure changes during cataract surgery through intraoperative images simulated from the “patient’s...  相似文献   
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