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981.
Phonological priming between bisyllabic (CV.CVC) spoken items was examined using both behavioral (reaction times, RTs) and electrophysiological (event-related potentials, ERPs) measures. Word and pseudoword targets were preceded by pseudoword primes. Different types of final phonological overlap between prime and target were compared. Critical pairs shared the last syllable, the rime or the coda, while unrelated pairs were used as controls. Participants performed a target shadowing task in Experiment 1 and a delayed lexical decision task in Experiment 2. RTs were measured in the first experiment and ERPs were recorded in the second experiment. The RT experiment was carried out under two presentation conditions. In Condition 1 both primes and targets were presented auditorily, while in Condition 2 the primes were presented visually and the targets auditorily. Priming effects were found in the unimodal condition only. RTs were fastest for syllable overlap, intermediate for rime overlap, and slowest for coda overlap and controls that did not differ from one another. ERPs were recorded under unimodal auditory presentation. ERP results showed that the amplitude of the auditory N400 component was smallest for syllable overlap, intermediate for rime overlap, and largest for coda overlap and controls that did not differ from one another. In both experiments, the priming effects were larger for word than for pseudoword targets. These results are best explained by the combined influences of nonlexical and lexical processes, and a comparison of the reported effects with those found in monosyllables suggests the involvement of rime and syllable representations.  相似文献   
982.
This paper highlights the importance of cavernous haemangiomas as clinically significant lesions and the role of imaging, particularly MRI, in suggesting the diagnosis. An understanding of the pathology of these lesions helps to explain the features demonstrated by imaging techniques.  相似文献   
983.
Carotid duplex ultrasound (CDUS) is a non-invasive technique used to assess the severity of carotid artery stenosis. It has been shown to have good correlation with digital subtraction angiography (DSA) but has been criticised for its variability. One source of this is the variation in results between studies responsible for re-validating velocity criteria to match the established treatment thresholds of internal carotid artery (ICA) stenosis. The aim of this study was to develop velocity criteria and determine the presence of inter-sonographer variation of CDUS when grading ICA stenosis in our department. Five sonographers measured the degree of ICA stenosis with CDUS in 33 patients who also underwent DSA. Receiver operator characteristic curve analysis was used to develop optimal velocity criteria for the 50%, 70% and 90% ICA stenosis thresholds as a group and for each individual sonographer. A peak systolic velocity ratio of > or = 3.25 was shown to have the highest accuracy (91.5%) for predicting a 70% stenosis. A moderate value of kappa (0.53 +/- 0.027) was calculated if the optimum velocity criterion was employed for each sonographer. There was no significant variation between the ability of sonographers to grade ICA stenosis (P > 0.05) and an excellent ICC of 0.911 was calculated. This study provides evidence to suggest that CDUS in our department is not an operator-dependant test for the investigation of ICA stenosis.  相似文献   
984.
Microarrays provide a versatile platform for utilizing information from the Human Genome Project to benefit human health. This article reviews the ways in which microarray technology may be used in breast cancer research. Its diverse applications include monitoring chromosome gains and losses, tumour classification, drug discovery and development, DNA resequencing, mutation detection and investigating the mechanism of tumour development.  相似文献   
985.
OBJECTIVE: To investigate the relationship between iron status in infancy and type of milk and weaning solids consumed. DESIGN: An observational cohort study. SETTING: 928 term infants from the Avon Longitudinal Study of Parents and Children in 1993-94. METHODS: Haemoglobin and ferritin concentrations at 8 and 12 months were assessed in relation to type and quantity of milk intake at 8 months. RESULTS: By WHO criteria, 22.7% of the infants were anaemic at 8 months and 18.1% at 12 months. More breast--than formula-fed infants were anaemic at 8 and 12 months. Cows' milk as the main drink was associated with increased anaemia at 12 months and low ferritin at 8 and 12 months. No association was found between any nutrients and haemoglobin concentrations. Protein and non-haem iron intakes were positively associated with ferritin concentrations and calcium intake negatively. This effect was more marked in infants being fed cows' milk. More than 25% of infants in the breast milk and cows' milk groups and 41% of infants having >6 breast feeds per day had iron intakes below the lower reference nutrient intake. Feeding cows' milk or formula above 600 ml or >6 breast feeds per day was associated with lower intakes of solids. CONCLUSIONS: Both breast and cows' milk feeding were associated with higher levels of anaemia. Satisfactory iron intake from solids in later infancy is more likely if formula intake is <600 ml per day and breast feeds are limited to <6 feeds per day. Cows' milk should be strongly discouraged as a main drink before 12 months.  相似文献   
986.
OBJECTIVE: To determine the cost effectiveness of a public health legislative/educational strategy to reduce tap water scalds in children less than 10 years of age. DESIGN: Cost-effectiveness analysis conducted from the government perspective over a 10-year time horizon. POPULATION: Children under 10 years of age in Ontario, Canada INTERVENTIONS: Legislation to set thermostat settings on new domestic water heaters to lower temperatures (maximum 49 degrees C) plus annual educational notices to utility customers versus status quo. MAIN OUTCOME MEASURES: The burden of tap water scalds, healthcare resource utilization, the cost and effectiveness of the proposed intervention, and the probabilities assigned to health outcomes were modeled in a decision analysis based on population-based data, patient charts, and the published medical literature. All costs and health outcomes beyond 1 year were discounted at 3%. RESULTS: An estimated 182 children under 10 require medical care for tap water scald injuries annually in Ontario (13.98 per 100,000). Of these, 65 require emergency department (ED) care only (median cost $C149 per injury), 103 require ED care with clinic follow-up ($C577 per injury), 14 require hospital admission ($C5203 per injury), and two require surgical skin grafting ($C28,526 per injury). The estimated cost of the intervention was $C51,000 annually, with a projected 56% reduction in tap water scald injuries. Over 10 years, the intervention group would show total costs of $C1.17 million and 704 scalds, compared with $C1.65 million and 1599 scalds in the status quo group. Therefore, the intervention would be cost saving, with an incremental ratio of $C531 saved per scald averted. Sensitivity analyses showed that the intervention would remain cost saving through a wide range of variable estimates. CONCLUSIONS: Legislation to lower thermostat settings on domestic water heaters plus annual educational notices to utility customers would generate cost savings while reducing the morbidity from tap water scalds in children.  相似文献   
987.
卢杰 《英国医学杂志》2007,10(5):266-267
近期的BMJ中,一位囊性纤维化病人讲述了自己伴随疾病从儿童到成人的经历(见本期第309页)。在很多的艰难险阻当中,她提到了从儿童期到成人期治疗的过渡是一条“崎岖之路”。她说当16岁时,她宁愿倾家荡产进入一家过渡诊所,也不愿意直接去另一家医院的成人诊所。[第一段]  相似文献   
988.
Kawasaki disease is a syndrome that usually occurs in infants and children. It is characterized by an exanthem, enanthem, fever, lymphadenopathy, and polyarteritis of variable severity. The present report describes cases in which an initial presentation of Kawasaki disease included abdominal and gastrointestinal symptomatology.  相似文献   
989.
990.
Striatal lesions disrupt both motor and cognitive performance in rats, many aspects of which can be restored by striatal transplants. Because the normal striatum is involved in the formation and maintenance of motor habits, it has been hypothesized that grafted animals may require explicit retraining to relearn previously established habits that have been disrupted by the lesions. We have used a lateralized-discrimination task to reproduce this "learning to use the transplant" effect, combined with a transfer-of-training paradigm to demonstrate that recovery requires relearning specific lateralized stimulus-response associations and cannot be explained simply by a generalized training-dependent improvement in motor skill. These results have clear implications for developing appropriate strategies for the rehabilitation of Huntington's disease patients participating in clinical transplantation programs.  相似文献   
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