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51.
Background: Stress management interventions for HIV-positive persons have been designed to enhance coping skills and encourage health-promoting behaviors with the hope of decreasing distress and slowing disease progression.Purpose: We examined the efficacy of a cognitive behavioral stress management (CBSM) intervention in combination with medication adherence training (MAT) in 130 gay and bisexual men living with HIV infection.Methods: Participants were randomized to either a 10-week CBSM+MAT intervention (n = 76) or a MAT-only condition (n = 54). Measures of self-reported adherence, active cognitive coping (i.e., acceptance and positive reinterpretation), avoidant coping (i.e., denial and behavioral disengagement), and depressed mood were examined over the 10-week intervention period.Results: Men in CBSM+MAT reported reductions in depressed mood and denial coping during the 10-week intervention period, but no changes in active cognitive coping or self-reported adherence were observed. Using path analysis, greater reliance on denial coping at baseline was associated with decreased depressed mood at 10 weeks. We also determined that CBSM+MAT may decrease depressed mood by reducing reliance on denial coping over the 10-week intervention period.Conclusions: Although denial may be an effective means of distress reduction in the short term, reliance on this coping strategy may result in a decreased capacity to effectively manage a variety of disease-related stressors in the long term. CBSM+MAT addresses this potentially detrimental pattern by teaching stress reduction skills that may decrease depressed mood via reduced reliance on denial coping. This research was supported by National Institute of Mental Health Grants P01 MH49548 and T32 MH18917.  相似文献   
52.
In this work we aimed to study the possibility of using supervised classifiers to quantify the main components of carotid atherosclerotic plaque in vivo on the basis of multisequence MRI data. MRI data consisting of five MR weightings were obtained from 25 symptomatic subjects. Histological micrographs of endarterectomy specimens from the 25 carotids were used as a standard of reference for training and evaluation. The set of subjects was divided in a training set (12 subjects) and an evaluation set (13 subjects). Four different classifiers and two human MRI readers determined the percentages of calcified tissue, fibrous tissue, lipid core, and intraplaque hemorrhage on the subject level for all subjects in the evaluation set. Quantification of the relatively small amounts of calcium could not be done with statistical significance by either the classifiers or the MRI readers. For the other tissues a simple Bayesian classifier (Bayes) performed better than the other classifiers and the MRI readers. All classifiers performed better than the MRI readers in quantifying the sum of hemorrhage and lipid proportions. The MRI readers overestimated the hemorrhage proportions and tended to underestimate the lipid proportions. In conclusion, this pilot study demonstrates the benefits of algorithmic classifiers for quantifying plaque components.  相似文献   
53.
We describe a patient with systemic lupus erythematosus and impaired renal function probably mainly due to tubulointerstitial disease. After a six-week course of low-dose cyclosporine A, she developed a severe but reversible loss of glomerular filtration rate and effective renal plasma flow despite of low cyclosporine A plasma levels. Based upon the observed fall of the filtration fraction, the rise in the relative clearance of 99Tc-dimercaptosuccinic acid and the increase in proteinuria, we suggest that in this case the tubules and/or interstitium are the main targets for cyclosporine A nephrotoxicity. Neither our patient's clinical symptoms nor her serologic parameters improved possibly because of the low dosage and/or short duration of cyclosporine A treatment. We conclude that one should be cautious when treating patients with systemic lupus erythematosus and pre-existing renal disease with cyclosporine A especially when tubulointerstitial abnormalities are present and/or other nephrotoxic drugs are used.  相似文献   
54.
The prevalent cohort study and the acquired immunodeficiency syndrome   总被引:2,自引:0,他引:2  
The acquired immunodeficiency syndrome (AIDS) is caused by a retrovirus, the human immunodeficiency virus (HIV). A rapid and convenient method to identify additional cofactors or risk modifiers and markers of disease progression is to study a cohort prevalent with HIV antibody. However, because the time of viral infection is usually unknown in the cohort, there are several potential sources of bias. Three sources of bias in a prevalent cohort study are identified assuming a proportional hazards model: onset confounding, differential length-biased sampling, and frailty selection. A number of problems in the interpretation of results on markers from a prevalent cohort also are considered. It is concluded that risk estimates derived from a prevalent cohort are not directly comparable to risk estimates derived from an incident cohort.  相似文献   
55.
56.
In 13 patients with myotonic dystrophy, oculomotor, auditory, and vestibular tests were performed. All 13 patients showed one or more abnormalities. There was a significant increase in the penetrance of the separate abnormalities with age. Saccadic slowing was found in 10 patients, in a severe form in three. Seven patients had a sensorineural high-tone hearing loss (30 to 85 dB at 8 kHz), which was in excess of that expected for their age, that could be attributed to myotonic dystrophy. Brain-stem auditory evoked potentials showed a significant interwave delay of the I-V interval (0.35 to 0.7 milliseconds). An abnormal vestibulo-ocular reflex was found in six patients; three had vestibular hyperreflexia with increased gain, and three had hyporeflexia with short time constants. This study confirms that in myotonic dystrophy, sensory system involvement can be found on both a peripheral and a central level.  相似文献   
57.
Changing economic, political, environmental, and social conditions continue to have a cumulative impact on Australian regional communities, and in many instances, rural communities are being forced to initiate their own strategies in order to remain economically and socially viable. However, while communities respond in differing ways to similar change events, as do individuals, research examining the change process has largely been undertaken at the individual level. This article reports on an investigation of the characteristics that moderate a community's ability to manage change and the types of collective coping strategies communities employ to deal with change events. A model of community change process was used as the framework to examine the links between community characteristics, appraisal of change events (forest restructuring and tourism), and the use of collective strategies in three communities in Western Australia. Findings suggest that a community's mobilization of strategies is dependent on the collective assessment of the change event, the nature of the event, and the characteristics of the community. The implications for intervention through policy and community development are discussed briefly. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 201–216, 2004.  相似文献   
58.
High intensity focused ultrasound: physical principles and devices.   总被引:7,自引:0,他引:7  
High intensity focused ultrasound (HIFU) is gaining rapid clinical acceptance as a treatment modality enabling non-invasive tissue heating and ablation for numerous applications. HIFU treatments are usually carried out in a single session, often as a day case procedure, with the patient either fully conscious, lightly sedated or under light general anaesthesia. A major advantage of HIFU over other thermal ablation techniques is that there is no necessity for the transcutaneous insertion of probes into the target tissue. The high powered focused beams employed are generated from sources placed either outside the body (for treatment of tumours of the liver, kidney, breast, uterus, pancreas and bone) or in the rectum (for treatment of the prostate), and are designed to enable rapid heating of a target tissue volume, while leaving tissue in the ultrasound propagation path relatively unaffected. Given the wide-ranging applicability of HIFU, numerous extra-corporeal, transrectal and interstitial devices have been designed to optimise application-specific treatment delivery. Their principle of operation is described here, alongside an overview of the physical mechanisms governing HIFU propagation and HIFU-induced heating. Present methods of characterising HIFU fields and of quantifying HIFU exposure and its associated effects are also addressed.  相似文献   
59.
In 32 patients with acute myocardial infarction, who had undergone successful intracoronary thrombolysis, the results of regional wall motion measured from contrast cineangiograms 10 to 21 days after thrombolysis were related to the results of thallium single-photon emission computed tomography (SPECT) after intravenous dipyridamole. Wall motion was measured by means of the centerline method, and thallium defect size was estimated by comparing the patient's circumferential profile with that of 20 normals. No correlation was found between ejection fraction or regional wall motion and thallium defect size. The time from symptom onset to thrombolysis was inversely correlated with the degree of hypokinesis (r=–0.51) but not with thallium defect size. In patients treated within 3 hours, hypokinesis was significantly less than in patients treated later (–1.1±0.6 SD vs –2.2±0.8 SD, p<0.01) whereas thallium defect size was not significantly different in both groups. It is concluded that, in patients after thrombolysis, thallium defect size determined by SPECT does not reflect the degree of left ventricular dysfunction.  相似文献   
60.
OBJECTIVES: To investigate whether any variables in a health-screened population study were associated with later development of large abdominal aortic aneurysms (AAA). SETTING: Malm?, Southern Sweden. MATERIAL AND METHODS: Within the Malm? Preventive Study 22,444 men and 10,982 women were investigated between 1974 and 1991. The mean age at the health screening was 43.7 years. RESULTS: After a median follow-up of 21 years, 126 men and six women (p<0.001) had large AAA that were symptomatic or evaluated for operation (5 cm diameter or more) or had autopsy-verified ruptured AAA. The male group (mean age 47 years) was, because of difference in age (p<0.001) also compared with an age-matched control group. The male patients with AAA showed increased diastolic blood pressure (p<0.007) at the health screening. Smoking predicted the development of AAA (p<0.0001). No difference in forced vital capacity or BMI was seen. Those who were physically inactive (e.g. not walking or cycling to work) had an increased risk of developing AAA (p<0.001). Among the laboratory markers measured, the erythrocyte sedimentation rate did not differ (7.1+/-5.9 vs. 6.4+/-5.7), but cholesterol (6.3+/-1.12 vs. 5.8+/-1.0) (p<0.0001) and triglycerides (1.9+/-0.12 vs. 1.5+/-0.07) (p<0.001) were significantly elevated in these individuals who subsequently developing AAA. The inflammatory proteins alfa-1-antitrypsin, ceruloplasmin, orosmucoid, fibrinogen, and haptoglobulin were increased (p<0.001). CONCLUSION: Male gender, smoking, physical inactivity and cholesterol are significant factors associated with the development of AAA.  相似文献   
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