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Decrease of benzodiazepine receptors in frontal cortex of alcoholics   总被引:4,自引:0,他引:4  
G Freund  W E Ballinger 《Alcohol》1988,5(4):275-282
We hypothesize that chronic alcohol abuse results in a loss of neurons and their associated synaptic receptors. This encephalopathy may be a precursor of brain atrophy and end-stage dementia. Autopsies were performed on normal brains of 27 alcoholics (mean age 62.5) and 30 nonalcoholic matched controls (mean age 64.4) free of other brain and liver diseases. None had recently received benzodiazepine medications. Gross brain atrophy was slight and equal in both groups. Benzodiazepine receptor densities and affinities in homogenates of frontal cortex were determined using [3H]flunitrazepam. Bmax specific binding was reduced by 20% in alcoholics compared with nonalcoholic controls of comparable age and with similar death-autopsy time intervals. The affinity was slightly less in the alcoholics. Wet tissue brain protein concentrations and their yields of 50,000-g pellet proteins were similar. Aging, death-autopsy time intervals, pneumonia and chronic obstructive pulmonary disease (diseases usually associated with hypoxia) had no significant effect on brain proteins, receptor densities, or affinities. We conclude that chronic alcoholism is associated with a loss of benzodiazepine receptor densities. Alcohol abuse may affect the results of post-mortem neurochemical investigations of other diseases.  相似文献   
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Objectives. We studied the duration and prognostic significance of atrial arrhythmias in the denervated transplanted heart, specifically the occurrence of atrial fibrillation in the absence of vagal modulation.

Background. Substantial animal data indicate that vagally induced dispersion of atrial refractoriness plays a central role in the induction and maintenance of atrial fibrillation.

Methods. We studied the occurrence of atrial arrhythmias in the denervated hearts of 88 consecutive orthotopic transplantations in 85 patients by means of continuous telemetry and all available electrocardiographic tracings.

Results. Fifty percent of recipients (44 of 88) developed at least one atrial arrhythmia. Atrial fibrillation occurred 23 times (21 recipients), atrial flutter 39 times (26 recipients), ectopic atrial tachycardia 3 times (3 recipients) and supraventricular tachycardia 18 times (11 recipients). The number of atrial fibrillation and atrial flutter episodes did not differ (23 vs. 39, p = 0.072), but the fibrillation (37.0 ± 10 vs. 6.6 ± 3.6 h, p = 0.014). Atrial fibrillation was associated with an increased risk of subsequent death (10 of 21 recipients with vs. 15 of 67 without atrial fibrillation, risk ratio 3.15 ± 0.18, p = 0.005 by Cox proportional hazards model). All 5 recipients who developed “late” atrial fibrillation (>2 weeks after transplantation) died versus 5 of 16 who developed atrial fibrillation within the first 2 weeks (p = 0.007). Causes of death included rejection (three recipients), allograft failure (two recipients), infection (three recipients) and multiorgan failure (two recipients). Atrial fibrillation was not associated with age, gender, ischemic time, reason for transplantation, echocardiographic variables, invasive hemodynamic variables or biopsy grade. Mean time from atrial arrhythmia to echocardiography was 2.7 ± 3.3 days; that to biopsy was 4.8 ± 6.3 days. Atrial flutter was not associated with subsequent death. Only 7 (15.9%) of 44 recipients demonstrated moderate or severe allograft rejection at the time of the arrhythmia.

Conclusions. Atrial arrhythmias occur frequently in the denervated transplanted heart, often in the absence of significant rejection. Late atrial fibrillation may be associated with an increased all-cause mortality.  相似文献   

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In a recent issue of Critical Care, Brandt and colleagues report the effects of a 'liberal' fluid loading protocol compared to a more 'restrictive' protocol on hemodynamics and mortality in pigs in which septic shock had been induced. It appears that the former protocol was associated with higher mortality in spite of improved hemodynamics compared to the latter. The results of the paper are discussed here in view of the scope and mechanisms of these findings. With regard to fluid resuscitation, they indicate that too much of an otherwise good thing is harmful, even if overhydration and edema formation seem to have been prevented. They also do not exclude a specific toxic effect of the larger volumes of hydroxyethyl starch in the 'liberal' strategy. The precise nature of a toxic effect remains obscure, however, but may involve the kidneys.  相似文献   
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Background Post‐inflammatory hyperpigmentation (PIH) is a common occurrence in patients with acne vulgaris, particularly in those with skin of colour. Aims A previous study has demonstrated the benefit of tretinoin (retinoic acid) in the treatment of PIH; however, there is currently no standard protocol to evaluate change in PIH following treatment. Based on these findings, we performed a pilot, exploratory, blinded, intraindividual‐controlled methodology study that consisted of a photographic assessment protocol with facial mapping. Materials and methods The study was based on a secondary analysis of a phase 4, community‐based trial of 544 acne patients who were treated with tretinoin gel microsphere 0.04% or 0.1%. Only patients with Fitzpatrick types III–V (skin of colour) were included in the study; subjects with Fitzpatrick skin type VI were excluded because the photographic assessment did not allow for proper evaluation. Results Despite the small number of subjects evaluated (n = 25), the results revealed consistent assessment of improvement in PIH between two independent graders (weighted κ = 0.84). Conclusion Further study with a larger population is recommended to validate the accuracy of this method.  相似文献   
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Objective: The purpose of the current study was to determine the self-reported prevalence of and factors associated with nonadherence with glaucoma medications in veteran outpatients.Methods: This survey study was conducted at a Veterans Affairs (VA) clinic. A survey was administered to patients with glaucoma. We calculated the percentage of self-reported adherence with glaucoma medications in each patient. Logistic regression was used to assess whether patient characteristics and difficulties with using glaucoma medications were related to patients' reporting that they were <100% adherent with their glaucoma medications in the previous week.Results: The survey was completed by 141 patients (men, 91.5%; mean [SD] age, 70.22 [11.60] years [range, 37–93 years]; black race, 45.4%; white race, 44.0%; “other” or data unavailable, 10.6%). Nonwhite patients were significantly less adherent in the previous week than were white patients (27.0% vs 11.3%; P < 0.05). A total of 67.4% patients reported ≥1 difficulty in using their glaucoma medications. The 3 most commonly reported difficulties were “drops fall on cheek” (29.1%), “too many drops come out” (20.6%), and “hard to read print” (17.0%). A total of 19.1% of patients self-reported using <100% of their glaucoma medications in the previous week. The number of difficulties reported was significantly associated with reporting being <100% adherent in the previous week (P<0.05).Conclusion: In this small sample of VA patients with glaucoma, adherence to glaucoma medications could be improved, especially among those who reported difficulties using their medications and those who were nonwhite.  相似文献   
60.

Background  

In patients with type 2 diabetes, the risk for cardiovascular disease is substantial. To achieve a more favourable risk profile, lifestyle changes on diet, physical activity and smoking status are needed. This will involve changes in behaviour, which is difficult to achieve. Cognitive behavioural therapies focussing on self-management have been shown to be effective. We have developed an intervention combining techniques of Motivational Interviewing (MI) and Problem Solving Treatment (PST). The aim of our study is to investigate if adding a combined behavioural intervention to managed care, is effective in achieving changes in lifestyle and cardiovascular risk profile.  相似文献   
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