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1.
Sixteen patients with stable chronic asthma participated in a double blind crossover study comparing the new inhaled long acting beta 2 agonist formoterol with salbutamol. Inhaled (n = 15) and oral steroid (n = 1) treatment were maintained at the same daily dose throughout the study. For four weeks the patients received either formoterol 24 micrograms twice daily or salbutamol 400 micrograms twice daily, plus additional puffs (with the same drug) when needed. Asthma symptoms, additional puffs of beta 2 agonist, peak expiratory flow (PEF), and side effects were recorded daily. During treatment with formoterol the patients used fewer additional puffs of beta 2 agonist, had better symptom scores, less disturbed sleep, more days without additional aerosol, and higher PEF both morning and evening than during salbutamol treatment. Thus formoterol 24 micrograms twice daily gave long lasting bronchodilatation and asthma symptoms were well controlled with regular twice daily administration.  相似文献   
2.
Clinical practice guidelines have been proposed to significantly reduce the gap between available scientific evidence and clinical practice. Evidence-based guidelines are also being produced at an ever-increasing pace. However, guidelines do not implement themselves, and the research to support implementation does not provide straightforward answers. What works in one setting does not necessarily work in another. In short, guideline implementation and change of practice is complex and messy. The purpose of this article is to discuss the implementation of clinical practice guidelines using the Promoting Action on Research Implementation in Health Services framework. More specifically, 3 key components are highlighted: (1) the evidence base for guideline recommendations, (2) the clinical context where guidelines are to be implemented, and (3) the nature of facilitation needed to ensure a successful change process. An overview of the literature in the field is provided, and the authors' experiences are shared, and a few recommendations are tentatively provided.  相似文献   
3.
All 170 patients (212 hips) treated between 1946 and 1992 for slipped capital femoral epiphysis (SCFE) with fixation in situ with a single device were reviewed to evaluate the incidence of further slipping of the epiphysis after primary treatment. In 154 hips, a smooth device without anchorage in the epiphysis was used and in 58, a device anchored in the epiphysis. In 3 hips, further slipping of the epiphysis occurred after primary treatment with no obvious cause. In 10 hips, an obvious cause for further slipping of the epiphysis was found. These 10 hips were re-operated due to the loss of epiphyseal grip in 6 hips, unsatisfactory placement of the device in 1, while in the remaining 3 hips, the device was removed before physeal closure. Twenty-six hips (12.3%) were re-operated because the device had lost its epiphyseal grip before physeal closure, and in 25 of these hips the device was smooth and had no anchorage in the epiphysis. The conclusion of this study is that a single device with anchorage in the epiphysis is stable enough to prevent further slipping of the epiphysis in hips with SCFE.  相似文献   
4.
It has been postulated that patients with chronic renal failure,even in the absence of cardiopulmonary symptoms, accumulateinterstitial pulmonary fluid, which is removed by haemodialysis.To test this hypothesis we used the indocyanine green (ICG)-heavywater double indicator dilution method to measure lung water,cardiac output, and central blood volume in relation to haemodialysis.Ten uraemic patients, without cardiopulmonary symptoms, wereinvestigated at the beginning and end, and 2 h after, a regulardialysis session. A group of 18 surgical patients about to undergoelective abdominal surgery served as controls. Despite normalgas exchange, central blood volume, and cardiac output at thestart of dialysis the mean (SD) lung water was significantlyhigher than in the control group [4.8 (0.9) compared with 3.6(0.7) ml/kg, P<0.001]. There was no correlation between weightgain between sessions of dialysis and the magnitude of lungwater at the start of dialysis. Lung water decreased (P <0.001)to the level of the control group in response to dialysis. Therewas no correlation between weight loss and reduction in lungwater induced by dialysis. In conclusion, we have verified thepresence of subclinical pulmonary oedema which was removed bydialysis in a group of patients with established renal failure.The variations in lung water cannot be explained by hydrostaticmechanisms alone.  相似文献   
5.
BACKGROUND AND OBJECTIVES: Apolipoprotein E (apoE) has been implicated in regenerative processes in the brain after trauma, as well as in the pathogenesis of Alzheimer's disease. Inheritance of a specific apo epsilon allele (apo epsilon 4) determines in part the risk and the mean age at onset of Alzheimer's disease. ApoE has been found to bind isoform specifically to beta-amyloid protein, the major component of senile plaques, and to the microtubule associated protein tau, which forms paired helical filaments and neurofibrillary tangles. The aim was to further examine the relation between apo epsilon alleles, especially apo epsilon 4, and the development of neuropathological changes associated with Alzheimer's disease. METHODS: Brains of patients with Alzheimer's disease (n = 44) and vascular dementia (n = 11) and of age matched controls (n = 29) were studied. Senile plaques and neurofibrillary tangles in the hippocampus and frontal cortex were quantified. RESULTS: No correlation was found between the number of apo epsilon 4 alleles and the number of senile plaques and neurofibrillary tangles in the hippocampus or the frontal cortex of patients with Alzheimer's disease, or vascular dementia, or control groups. No significant differences in duration or severity of dementia were found between patients with or. without the apo epsilon 4 allele. No increased frequency of apo epsilon 4 was found in vascular dementia. CONCLUSION AND COMMENT: Although the apo epsilon genotype clearly affects whether Alzheimer's disease will develop or not, the present study suggests that it has no influence on pathology or clinical intellectual status, once the dementia has manifested itself. No increased apo epsilon 4 allele frequency was found in neuropathologically diagnosed patients with vascular dementia in whom concomitant Alzheimer's disease can be excluded.  相似文献   
6.
7.
A case of nephrotic syndrome and acute renal failure in a 74-year-old man with latent syphilis is described. A renal biopsy demonstrated focal global sclerosis in three of nine glomeruli, however, the remaining glomeruli revealed typical lesions of minimal change disease. Previous reports of renal involvement in syphilis have described membranous glomerulonephritis, mesangial and endothelial cell proliferative glomerulonephritis, and, recently, rapidly progressive glomerulonephritis. The proteinuria and renal failure resolved after penicillin therapy alone. This response strongly suggested that there was a causal relationship between the syphilis and the nephrotic syndrome. This is the first report of such a relationship.  相似文献   
8.
CT evaluation of coverage and congruency of the hip prior to osteotomy   总被引:5,自引:1,他引:4  
A computer-assisted model has been developed to improve the results of surgical techniques for reconstruction of hip dysplasia. This method assesses the coverage and congruency of the femoral head by evaluating multiple factors that may influence surgical planning. It achieves a more reliable image because the measurements are based on a three-dimensional representation, and attention is focused on the cartilaginous coverage of the femoral head. A method to simulate the operative correction helps the surgeon in planning osteotomies of the femur and pelvis. This technique clearly establishes both deficiencies of coverage and congruency of pathologic hips and thus may be used to create a more precise definition and treatment of multiple congenital abnormalities.  相似文献   
9.
10.
Background: Pulmonary oedema is life threatening. A method is needed for reliable measurement of lung water in man in order to clarify aetiology, pathophysiology, prognosis, and to evaluate treatments against pulmonary oedema. Methods: The double-indicator dilution method with bolus injection and optical detection of heavy water and indocyanine green in arterial blood for the measurement of cardiac output, central blood volume and lung water was applied in two human and two experimental studies. In parallel, the thermo-dye technique was tested in one of the experimental studies. The results from these four studies, together with results presented in the literature, were analysed according to the criteria set forth by The National Institute of Health, USA 1985, for the measurement of lung water in man, that is versatility, reproducibility, sensitivity, and accuracy. Results: for the heavy water-indocyanine green method: Versatility: No adverse reaction was recorded in the two human studies. A central venous line and a peripheral arterial line, or access to an arterio-venous fistula, were needed for bolus injection and concentration analysis. In-line optical detection of heavy water and indocyanine green did not expose the subjects to radio-labelled isotopes and the blood loss was low compared to timed blood volume collection. Reproducibility: The coefficient of variation was below 10% for cardiac output and central blood volume, and 10–17% for lung water. Sensitivity: Changes in lung water that were below the level of gas exchange disturbance could be detected in a group of subjects. Accuracy: Cardiac output, mean transit time and lung water for heavy water were linearly related to independent reference measures. Evidence for barrier limitations for heavy water in the clinical setting were weak. The indicator dilution method is unreliable for shock states and pulmonary embolism. Results: for the thermo-dye method: Versatility: The method did not expose the subjects to radio-labelled isotopes and there was no blood loss, but the method requires a central venous line and a thermistor-equipped fibre-optic catheter placed in the aorta. Reproducibility: The coefficient of variation was approximately 10% for cardiac output, central blood volume and lung water. Sensitivity: In healthy lungs, small differences in lung water can be detected. In pulmonary oedema, the large increase in deviation cripples the sensitivity of the method. Accuracy: Recovery of the thermal indicator and the error in its mean transit time were dependent on the distribution volume for the indicator cold. This undermines reliable calculation of cardiac output and lung water. Conclusions: The method using optical detection of heavy water and indocyanine green in blood for the measurement of cardiac output, central blood volume and lung water in humans is an improvement with regard to radio-labelled methods, with the same reproducibility. The method allows for detection of small changes in lung water under the range where gas-exchange disturbance occurs. The method provides values close to gravimetric lung water values in both healthy and grossly oedematous lungs, independent of cardiac output and distribution volume, with the exception of shock states and severe vascular obstruction.  相似文献   
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