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991.
ObjectiveThis study focused on geographic clustering of breast cancer based on residence in early life and identified spatio-temporal clustering of cases and controls. Methods: Data were drawn from the WEB study (Western New York Exposures and Breast Cancer Study), a population-based case–control study of incident, pathologically confirmed breast cancer (1996–2001) in Erie and Niagara counties. Controls were frequency-matched to cases on age, race, and county of residence. All cases and controls used in the study provided lifetime residential histories. The k-function difference between cases and controls was used to identify spatial clustering patterns of residence in early life. Results: We found that the evidence for clustered residences at birth and at menarche was stronger than that for first birth or other time periods in adult life. Residences for pre-menopausal cases were more clustered than for controls at the time of birth and menarche. We also identified the size and geographic location of birth and menarche clusters in the study area, and found increased breast cancer risk for pre-menopausal women whose residence was within the cluster compared to those living elsewhere at the time of birth. Conclusion: This study provides evidence that early environmental exposures may be related to breast cancer risk, especially for pre-menopausal women.  相似文献   
992.
OBJECTIVES: To test the hypothesis that impaired hemodynamic orthostatic changes commonly observed in the elderly may be related to age-related increase in arterial wall stiffness. DESIGN: Convenience sample of consecutive patients admitted for falls. SETTING: Acute- and intermediate-care geriatric ward of a French hospital. PARTICIPANTS: Fifty-seven elderly patients (46 women) consecutively admitted to a geriatric ward with a history of recent falls. MEASUREMENTS: Orthostatic hypotension (OH) was assessed using blood pressure measurements in the supine position and 1, 2, and 3 minutes after standing. Arterial wall stiffness was assessed using upper-limb and aortic pulse-wave velocities, measured with an external pressure transducer connected to a computer. RESULTS: OH was present in 18 patients with a mean age+/-standard deviation of 85.4+/-7.6 (5 men, 13 women) and absent in 39 patients aged 83.7+/-6.2 (6 men, 33 women). Upper-limb pulse-wave velocity was significantly higher, by 16%, in patients with OH than those without (9.91 vs 8.53 m/s; P<.02). Significant correlations were found between upper-limb pulse-wave velocity and systolic blood pressure changes after 1 minute of standing (r=0.263, P<.05) and maximal diastolic blood pressure change after standing (r=0.351, P<.01). CONCLUSION: Upper-limb arterial wall stiffness was significantly greater in elderly patients with OH than in patients without OH and was significantly related to blood pressure changes after standing. These results highlight the possible role of age-related changes in the arterial tree in the hemodynamic response to orthostatic challenges.  相似文献   
993.
Data from a six-year follow-up of Trypanosoma cruzi-infected adolescents enrolled in a randomized, double-blind, clinical trial of benznidazole showed successful chemotherapy in 64.7% (95% confidence interval [CI] = 50.2-78.7) and 84.7% (95% CI = 66.8-92.9), respectively, by intention-to treat and by per protocol analysis measured by seronegativity in a chemiluminescent enzyme-linked immunosorbent assay with a purified trypomastigote mucin antigen. No incident case of cardiomyopathy was detected by electrocardiogram assessment in this cohort of adolescents who had been infected in childhood. The persistent and consistently long-term negative serologic reactions suggest the absence of the parasite in the treated patients and reinforces the recommendation of early benznidazole chemotherapy for T. cruzi-infected infants as a public health policy in endemic areas.  相似文献   
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996.
BACKGROUND: Treatment of deep-vein thrombosis (DVT) with a once-daily regimen of enoxaparin, rather than a continuous infusion of unfractionated heparin (UFH) is more convenient and allows for home care in some patients. This study was designed to compare the efficacy and safety of these two regimens for the treatment of patients with proximal lower limb DVT. METHODS: 201 patients with proximal lower limb DVT from 13 centers in Brazil were randomized in an open manner to receive either enoxaparin [1.5 mg/kg subcutaneous (s.c.) OD] or intravenous (i.v.) UFH (adjusted to aPTT 1.5-2.5 times control) for 5-10 days. All patients also received warfarin (INR 2-3) for at least 3 months. The primary efficacy endpoint was recurrent DVT (confirmed by venography or ultrasonography), and safety endpoints included bleeding and serious adverse events. The rate of pulmonary embolism (PE) was also collected. Hospitalization was at the physician's discretion. RESULTS: Baseline patient characteristics were comparable between groups. The duration of hospital stay was significantly shorter with enoxaparin than with UFH (3 versus 7 days). In addition, 36% of patients receiving enoxaparin did not need to be hospitalized, whereas all of the patients receiving UFH were hospitalized. The treatment duration was slightly longer with enoxaparin (8 versus 7 days). There was a nonsignificant trend toward a reduction in the rate of recurrent DVT with enoxaparin versus UFH, and similar safety. CONCLUSIONS: A once-daily regimen of enoxaparin 1.5 mg/kg subcutaneous is at least as effective and safe as conventional treatment with a continuous intravenous infusion of UFH. However, the once daily enoxaparin regimen is easier to administer (subcutaneous versus intravenous), does not require aPTT monitoring, and leads to both a reduced number of hospital admissions and an average 4-day-shorter hospital stay.  相似文献   
997.
Stigma in society causes harm to people with severe mental illness (SMI) and internalized stigma represents its psychological point of impact. We evaluated the extent of internalized stigma in a sample of outpatients with SMI, using the Internalized Stigma of Mental Illness (ISMI) Scale, developed with consumer input. About a third of the sample reported high levels of internalized stigma. We tested whether internalized stigma predicted increased depressive symptoms and reduced self-esteem at 4-month follow-up, controlling for baseline levels. Depression was predicted by Alienation, Stereotype Endorsement, Social Withdrawal Scales and total ISMI score. Reduced self-esteem was predicted by Alienation. ISMI results were stronger than those for the widely used Devaluation–Discrimination Scale. The finding that alienation further reduces morale speaks to the difficulty of pulling oneself out of this type of vicious cycle without assistance.  相似文献   
998.
Specialised brain structures allow songbirds to process acoustic signals. One of these brain areas, the NCM (caudomedial neostriatum), shows an immediate-early gene ZENK response when a bird hears a conspecific song. Using a neuro-ethological approach, we investigate if high level of background noise added to conspecific song can modify this song-induced genic activation. We test the ZENK activation in the NCM of adult male Zebra finches Taeniopygya guttata (n = 17) by playing back conspecific signals mixed with different levels of noise, the successful discrimination being reflected by the birds' (n = 6) behavioural responses to these stimuli. From our results, it appears that a high genic activation of the NCM does not necessarily require the audition of an undegraded species-specific signal. Nevertheless, it requires that the signal still contains sufficient information to elicit a behavioural response. The genic activation of the NCM remains thus stable against very high levels of a wide-band background noise, as far as the signal recognition remains possible for the bird.  相似文献   
999.
We studied the involvement of hippocampal protein synthesis-, PKA-, and MAP kinase-dependent processes in short- (STM) and long-term memory (LTM) for inhibitory avoidance task. Fifteen minutes before or immediately after training rats received intrahippocampal infusions of vehicle, the protein synthesis inhibitor anisomycin, the PKA inhibitor Rp-cAMPs or the MAPKK inhibitor PD098059. The results show that STM recruits PKA and MAPK, whereas, LTM depends on PKA activity and protein synthesis during the early post-training period.  相似文献   
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