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991.
992.
A 77-year-old woman was admitted to the intensive care unit after successful cardiopulmonary resuscitation for out-of-hospital cardiac arrest due to pulseless electrical activity. She was treated with mild therapeutic hypothermia to minimise secondary anoxic brain damage. After a 24 h period of therapeutic hypothermia with a temperature of 32.5 degrees C, the patient was rewarmed and sedation discontinued. Neurological evaluation after 24 h revealed a maximum Glasgow Coma Score of E4M4Vt with spontaneous breathing. However the patient developed a fever reaching 39 degrees C for several hours that was unresponsive to conventional cooling methods. In the subsequent 24 h patient developed apnoea, hypotension and bradycardia with deterioration of the coma score. Diabetes insipidus was confirmed. Cerebral CT was performed which showed diffuse brain oedema with herniation and brainstem compression. The patient died within hours. Autopsy showed massive brain swelling and tentorial herniation. Hyperthermia possibly played a pivotal role in the development of this fatal insult to this vulnerable brain after cardiac arrest and therapeutic hypothermia treatment. The acute histopathological alterations in the brain, possibly caused by the deleterious effects of fever after cardiac arrest in human brain, may be considered a new observation.  相似文献   
993.
INTRODUCTION: In Sweden, voluntary adverse drug reaction (ADR) reporting started over 40 years ago to detect rare, serious, unexpected adverse, mainly type B, reactions. During the period 1965-2004, 92,000 reports were assessed. Since certain nurses are licensed to prescribe a limited number of drugs, nurses also form part of the reporting team. AIM: To analyse the ADR reporting by nurses in Sweden. METHODS: All reports by nurses and other health-care personnel entered into the Swedish ADRs database SWEDIS (Swedish Drug Information System) were retrieved for the 10-year period 1995-2004 (Swedish population: 9 million). The intention was to analyse the nurses' reports from a quantitative and qualitative point of view. RESULTS: The total number of ADR reports has gradually increased during the past 10 years from 3000 to over 4000 in 2004 (465 per million inhabitants), an increase by 28%. All ADR reports originate from health care personnel. The nurses' contribution to the ADR reporting increased from 2-3% in the mid-90s to 12% in 2004. The most common drugs involved in the nurses' reporting were various kinds of vaccines. Skin reactions dominated among the nurses' ADR reports. The ADRs reported by nurses were, as a consequence of many vaccine reports, compared to all reports, not so often classified as serious, but were on the other hand more often assessed with a causal relationship. CONCLUSIONS: Nurses, in their position as drug administrators who record signs and symptoms of the patients, play an increasingly important role for detection of suspected ADRs and are now contributing to a significant amount of the ADR reporting in Sweden.  相似文献   
994.
995.

Background and purpose

Benzylidene-anabaseines (BAs) are partial agonists of the α7 nicotinic acetylcholine receptor (nAChR) but their mechanism(s) of action are unknown. Our study explores several possibilities, including direct interactions of BAs with the nAChR channel.

Experimental approach

Functional and radioligand-binding assays were used to examine the interaction of two BA analogues, 3-(2,4-dimethoxybenzylidene)-anabaseine (DMXBA) and its primary metabolite 3-(4-hydroxy-2-methoxybenzylidene)-anabaseine (4OH-DMXBA) with both agonist and non-competitive antagonist (NCA)-binding sites on muscle-type nAChRs.

Key results

Both BAs non-competitively inhibited ACh activation of human fetal muscle nAChRs and sterically inhibited the specific binding of the NCAs [piperidyl-3,4-3H(N)]-(N-(1-(2-thienyl)cyclohexyl)-3,4-piperidine ([3H]TCP) and [3H]dizocilpine to Torpedo nAChRs in the desensitized state. These compounds modulated [3H]tetracaine, [14C]amobarbital and [3H]TCP binding to resting nAChRs by allosteric mechanisms. Both BAs enhanced [3H]TCP binding when the nAChR was initially in the resting but activatable state, suggesting that both compounds desensitized the Torpedo nAChR. Although DMXBA failed to activate human fetal muscle nAChRs, 4OH-DMXBA was found to be a partial agonist. [3H]Nicotine competition-binding experiments confirmed that 4OH-DMXBA has higher affinity than DMXBA for the agonist sites, and that DMXBA is also a competitive antagonist.

Conclusions and implications

3-(4-hydroxy-2-methoxybenzylidene)-anabaseine is a partial agonist for human fetal muscle nAChRs, whereas DMXBA only has competitive and NCA activities. The NCA-binding site for BAs overlaps both the phencyclidine-and dizocilpine-binding sites in the desensitized Torpedo nAChR ion channel. The desensitizing property of BAs suggests another possible mode of non-competitive inhibition in addition to direct channel-blocking mechanisms.  相似文献   
996.

Background

Transfusion of bacterially contaminated blood can result in sepsis and will constitute a substantial health burden to the patient.

Objective

To assess the level of transfusion related sepsis and the bacterial types responsible for the contamination at the Tamale Teaching Hospital in Ghana.

Method

We sampled 80 refrigerated donor blood at the blood bank and cultured them for bacteria. The antimicrobial sensitivities of the isolates were also determined.

Results

14 blood bags representing 17.5% grew isolates of various bacteria. Ten (10) of the 14 isolates were Gram positive cocci representing 71.42% making it the commonest contaminant. 50% of the gram positive cocci were identified to be coagulase negative staphylococci and 21.42% were Staphylococcus aureus. There were 14.28% isolates which were Gram positive rods, and were identified to be Corynebacterium diphtheroids. There were two isolates which were Gram negative rods; one was identified as Escherichia coli and the other one Klebsiella pneumoniae. Sensitivity among the organisms were varied; as all the 14 (100%) of the organisms isolated were sensitive to amikacin, only 14.28% of the coagulase negative staphylococci were sensitive to co-trimoxazole, 28.5% were sensitive to ampicillin, 42.8% were sensitive to cefuroxime and 71.4% were sensitive to ciprofloxacin. Sensitivity to gentamicin was observed to be 85.7% and 28.5% were sensitive to Tetracycline. Only the 10 Gram positive cocci were tested against erythromycin and Cloxacillin; where 70.00% were sensitive to cloxacillin and 90% were sensitive to erythromycin.

Conclusion

All the Staphylococcus aureus isolated were resistant to both ampicillin and cotrimoxazole. Potential dangers and consequences of transfusing multidrug resistance bacteria have been discussed.  相似文献   
997.

Background  

The treatment of patients with haematological malignancies by means of haematopoietic stem cell transplantation (HSCT) is often accompanied by life threatening infections. With emerging antimicrobial resistance there is an increased need for new agents, with a beneficial safety profile. Therefore we evaluated the safety of the promising new antimicrobial peptide human lactoferrrin 1-11 (hLF1-11) in healthy volunteers and patients.  相似文献   
998.
999.
Current models of the basal ganglia and dopamine neurons emphasize their role in reinforcement learning. However, the role of dopamine neurons in decision making is still unclear. We recorded from dopamine neurons in monkeys engaged in two types of trial: reference trials in an instructed-choice task and decision trials in a two-armed bandit decision task. We show that the activity of dopamine neurons in the decision setting is modulated according to the value of the upcoming action. Moreover, analysis of the probability matching strategy in the decision trials revealed that the dopamine population activity and not the reward during reference trials determines choice behavior. Because dopamine neurons do not have spatial or motor properties, we conclude that immediate decisions are likely to be generated elsewhere and conveyed to the dopamine neurons, which play a role in shaping long-term decision policy through dynamic modulation of the efficacy of basal ganglia synapses.  相似文献   
1000.
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