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991.
We assessed the rate of recovery of fluoroquinolone-resistant and fluoroquinolone-susceptible Escherichia coli isolates from culture of frozen perirectal swab samples compared with the results for culture of the same specimen before freezing. Recovery rates for these 2 classes of E. coli were 91% and 83%, respectively. The majority of distinct strains recovered from the initial sample were also recovered from the frozen sample. The strains that were not recovered were typically present only in low numbers in the initial sample. These findings emphasize the utility of frozen surveillance samples.  相似文献   
992.
Background A discipline which critically looks at the evidence for practice should itself be critically examined. Credible evidence for the effectiveness of training in evidence-based healthcare (EBHC) is essential. We attempted to summarise the current knowledge on evaluating the effectiveness of training in EBHC while identifying the gaps. Methods A working group of EBHC teachers developed a conceptual framework of key areas of EBHC teaching and practice in need of evidence mapped to appropriate methods and outcomes. A literature search was conducted to review the current state of research in these key areas. Studies of training interventions that evaluated effectiveness by considering learner, patient or health system outcomes in terms of knowledge, skills, attitude, judgement, competence, decision-making, patient satisfaction, quality of life, clinical indicators or cost were included. There was no language restriction. Results Of 55 articles reviewed, 15 met the inclusion criteria: six systematic reviews, three randomised controlled trials and six before-after studies. We found weak indications that undergraduate training in EBHC improves knowledge but not skills, and that clinically integrated postgraduate teaching improves both knowledge and skills. Two randomised controlled trials reported no impact on attitudes or behaviour. One before-after study found a positive impact on decision-making, while another suggested change in learners' behaviour and improved patient outcome. We found no studies assessing the impact of EBHC training on patient satisfaction, health-related quality of life, cost or population-level indicators of health. Conclusions Literature evaluating the effectiveness of training in EBHC has focused on short-term acquisition of knowledge and skills. Evaluation designs were methodologically weak, controlled trials appeared inadequately powered and systematic reviews could not provide conclusive evidence owing to weakness of study designs.  相似文献   
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Harris GD 《Primary care》2000,27(3):767-84;vii-viii
Advances in the understanding of the pathophysiology, diagnosis, and medical and surgical management of neonates with cardiovascular disease has led to their improved survival rates. These improvements have resulted in an increased number of pediatric patients presenting to the primary care physician's office with underlying heart disease. Understanding the genetic, congenital, or acquired etiologies to the various pediatric heart diseases is crucial to preventing these lesions and treating these patients.  相似文献   
995.
Multichannel tetrode array recording in awake behaving animals provides a powerful method to record the activity of large numbers of neurons. The power of this method could be extended if further information concerning the intracellular state of the neurons could be extracted from the extracellularly recorded signals. Toward this end, we have simultaneously recorded intracellular and extracellular signals from hippocampal CA1 pyramidal cells and interneurons in the anesthetized rat. We found that several intracellular parameters can be deduced from extracellular spike waveforms. The width of the intracellular action potential is defined precisely by distinct points on the extracellular spike. Amplitude changes of the intracellular action potential are reflected by changes in the amplitude of the initial negative phase of the extracellular spike, and these amplitude changes are dependent on the state of the network. In addition, intracellular recordings from dendrites with simultaneous extracellular recordings from the soma indicate that, on average, action potentials are initiated in the perisomatic region and propagate to the dendrites at 1.68 m/s. Finally we determined that a tetrode in hippocampal area CA1 theoretically should be able to record electrical signals from approximately 1, 000 neurons. Of these, 60-100 neurons should generate spikes of sufficient amplitude to be detectable from the noise and to allow for their separation using current spatial clustering methods. This theoretical maximum is in contrast to the approximately six units that are usually detected per tetrode. From this, we conclude that a large percentage of hippocampal CA1 pyramidal cells are silent in any given behavioral condition.  相似文献   
996.
OBJECTIVE: Low muscle strength is associated with poorer physical function, but limited empirical evidence is available to prove the relationship between muscle mass and physical function. We tested the hypothesis that persons with lower muscle mass or muscle strength have poorer lower-extremity performance (LEP). DESIGN: A cross-sectional, population-based study. PARTICIPANTS: A cohort of 449 men and women aged 65 years and older living in Amsterdam and its surroundings participating in the second examination (1995-1996) of the Longitudinal Aging Study Amsterdam. MEASUREMENTS: Leg skeletal muscle mass was measured using dual-energy X-ray absorptiometry (DXA). Grip strength was used as an indicator of muscle strength. Timed functional performance tests, including walking and repeated chair stands, were used to assess LEP. RESULTS: After adjustment for body height and age, leg muscle mass was positively associated with LEP in men (regression coefficient 0.178 [95% confidence interval 0.013-0.343], P = .035). In women an inverse association was observed, which became positive after additional adjustment for body mass index (BMI) (0.202 [-0.001-0.405], P = .052). Grip strength was positively associated with LEP in men and women. After additional adjustment for behavioral, physiological, and psychological variables, the associations between leg muscle mass and LEP disappeared, whereas grip strength remained to be independently associated with LEP in men (0.079 [0.042-0.116], P = .0001), with a tendency in women (0.046 [-0.009-0.101], P = .11). Results were similar when quartiles of leg muscle mass or grip strength were used. CONCLUSIONS: These results suggest that low muscle strength, but not low muscle mass, is associated with poor physical function in older men and women. However, prospective studies are needed to investigate the association between loss of muscle mass and physical function.  相似文献   
997.
Sixty nine patients with meningococcal disease some of whom presented with a maculopapular rash were entered in a prospective multicentre study. The clinical and laboratory features of children presenting with maculopapular rashes were compared with those of children presenting with typical haemorrhagic rashes. Of the 69 children 26 (38%) developed maculopapular rashes; nine (13%) had a maculopapular rash only, and the remaining 17 had a mixed maculopapular-purpuric rash. Twelve of the 17 (7%) had less than 12 petechiae. Children with maculopapular rashes had significantly higher platelet counts (median 294 compared with 243 x 10(9)/l), and plasma total haemolytic complement activity (80.5 compared with 65.0 U/ml) and significantly lower Glasgow meningococcal septicaemia prognostic scores (2.5 compared with 5.5) than those with purpuric rashes on admission. There were no significant differences between the groups in mortality, white cell count or absolute neutrophil count on admission, or C reactive protein concentration. Meningococcal disease can present with a maculopapular rash alone but this does not necessarily mean that the disease is less severe.  相似文献   
998.
The transoropalatal approach to the atlantoaxial-clival area provides excellent exposure for neurosurgical decompression and fusion procedures. The technique has been effectively applied in the treatment of bony and soft tissue abnormalities of the anterior spinal region. Although this approach is safe and reliable, it is not part of the otolaryngologist's usual surgical armamentarium. In the present study, we describe the case histories of five patients who underwent resection of the odontoid process for cervicomedullary compression. Neurological compromise was manifested by progressive upper and/or lower extremity paresis in all patients. In each patient, a transoropalatal approach was used. The surgical technique is discussed, and the prevention of possible sequelae, including velopharyngeal incompetence and palatal or pharyngeal wound dehiscence, is addressed.  相似文献   
999.
1000.
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