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991.
Spontaneous bone healing in the rabbit   总被引:2,自引:0,他引:2  
Cranioplasty is the most common method for correcting cranial defects. A number of innovations have been made to optimize bone repair. Before their use in humans, extensive animal trials must be performed to establish efficacy. However, the literature provides only scant and inconsistent data regarding animal controls. The purpose of this study, therefore, was to determine the critical size cranial defect in the rabbit model. Cranial defects ranging from 0.5 to 1.5 cm were created in 18 New Zealand White rabbits. The rabbits were then killed at 9 and 18 weeks and the defects examined using CT imaging and histologic analysis to determine bone healing. It was determined that cranial defects greater than 1.5 cm failed to heal spontaneously. Thus, the critical size cranial defect in the rabbit model is 1.5 cm.  相似文献   
992.
OBJECTIVE: To examine upper-extremity motor recovery of subjects with tetraplegia with both complete and incomplete injuries, to predict which patients and at what time they would recover a motor level. DESIGN: Prospective, multicenter clinical study of upper-extremity motor recovery in subjects with acute traumatic spinal cord injury. SETTING: Three regional spinal cord injury centers. SUBJECTS: One hundred sixty-seven individuals with acute traumatic tetraplegia (144 males [86%], and 23 females [14%]) between the ages of 15 and 75 years (mean age, 35.5 yrs). METHODS: Subjects were examined and classified using sequential manual muscle tests performed on admission, 72 hours, 1, 2, and 3 weeks, and 1, 2, 3, 6, 12, 18, and 24 months postinjury. C5 biceps, C6 extensor carpi radialis, C7 triceps, and C8 flexor digitorum profundus were evaluated using a 0-5 scale. Analyses of the right motor levels used a series of logistic regression models, and for multiple measurements on each subject, models were estimated using generalized estimating equations. RESULTS: The analysis for recovery of the biceps for the C4 group showed 70% of complete compared with 90% of incomplete injuries recovered (p < .001); of the extensor carpi radialis in the C5 group, 75% complete and 90% incomplete recovered (p < .002); and of the triceps in the C6 group, 85% of complete and 90% of incomplete injuries recovered (p < .16). CONCLUSION: Predicting future potential for upper-extremity motor recovery and for independence in self-care in groups of patients at a specific motor level is possible within the first week of injury.  相似文献   
993.
994.
S-Methylation by thiopurine methyltransferase (TPMT) is an important route of metabolism for the thiopurine drugs. About one in 300 individuals are homozygous for a TPMT mutation associated with very low enzyme activity and severe myelosuppression if treated with standard doses of drug. To validate the use of molecular genetic techniques for the detection of TPMT deficiency, we have determined red blood cell TPMT activity in 240 adult blood donors and 55 normal children. Genotype was determined by restriction fragment length analysis of polymerase chain reaction products in a cohort of 79 of the blood donors and five cases of azathioprine-induced myelosupression, and this confirmed a close relationship between genotype and phenotype. In 17 of the 24 cases in which mutations were found, DNA was also available from remission bone marrow. In one of these cases, DNA from the remission marrow sample indicated the presence of a non-mutated allele that had not been seen in the blast DNA sample obtained at presentation. These results indicate that polymerase chain reaction-based assays give reliable and robust results for the detection of TPMT deficiency, but that caution should be exercised in relying exclusively on DNA obtained from lymphoblasts in childhood leukaemia.  相似文献   
995.

Background  

Primary care internationally is approaching a new paradigm. The change agenda implicit in this threatens to de-stabilise and challenge established general practice and primary care.  相似文献   
996.

Background  

The workplace is an ideal setting for health promotion. Helping employees to be more physically active can not only improve their physical and mental health, but can also have economic benefits such as reduced sickness absence. The current paper describes the development of a three month theory-based intervention that aims to increase levels of moderate intensity physical activity amongst employees in sedentary occupations.  相似文献   
997.
This study examines the correlates of marital satisfaction using data from a national probability sample of African Americans (N = 962) and Black Caribbeans (N = 560). Findings reveal differences between African Americans and Black Caribbeans, and men and women within those groups, in the predictors of marital satisfaction. Black Caribbean women reported overall higher levels of marital satisfaction than African American women. The findings amply demonstrate the significance of ethnic diversity within the Black population in the United States. Difficulties with finances (budgeting, credit issues, and debt management) are one of the key issues that generate conflict in marriages; stress generated as a result of financial problems can lower marital satisfaction. Because these issues are salient for couples at any given time in the family life cycle, counseling at critical points in the marriage (birth of children, launching of children from home, and retirement) may be helpful.  相似文献   
998.
Alkaloids in Sophora alopecuroides seed and relevant tests for activity]   总被引:2,自引:1,他引:2  
Seven alkaloids were isolated from the seed of Sophora alopecuroides and identified to be oxymatrin, oxysophocarpine, cytisine, matrine, sophocarpine, sophoridine and nicotine respectively by comparing chromactographic and spectral characteristics with authentic known compounds. Nicotine was isolated from Sophora for the first time. The activity of extracts and alkaloids against cancer, virus, dermatophytes and bacteria was carried out in vitro.  相似文献   
999.
The validity of self-reported fruit and vegetable intake in minority populations has not been adequately established. In this study, the authors examined the association of three food frequency questionnaires (FFQs) and 24-hour dietary recalls with serum carotenoid levels. Approximately 1,000 African-American adults recruited from 15 churches in Atlanta, Georgia (1997-1998) completed three fruit and vegetable FFQs: a seven-item instrument assessing intake during the past month; a two-item measure assessing usual intake; and a 36-item measure adapted from the Health Habits and History Questionnaire. A total of 414 participants received a 24-hour recall by telephone, and 105 of them received two additional recalls. Serum levels of lycopene, lutein, cryptoxanthin, alpha-carotene, and beta-carotene were assessed in 813 participants and used as the validity criterion. The correlations of fruit and vegetable servings with specific and total serum carotenoid levels were generally higher for the 36-item FFQ than for the two-item and seven-item instruments. The strongest correlation of fruit and vegetable servings with total carotenoid levels was observed for the three recalls (r = 0.42), with the 36-item FFQ and the single 24-hour recall yielding comparable correlations (r = 0.35 and r = 0.37, respectively). The validity of the 36-item fruit and vegetable FFQ was generally as strong as the validity of both 1 and 3 days of recalls. Given the lower cost and time needed for administration relative to recalls, it appears that the 36-item FFQ has merit for evaluating fruit and vegetable health interventions.  相似文献   
1000.
Prostate cancer and dietary carotenoids   总被引:10,自引:0,他引:10  
This population-based case-control study investigated associations between prostate cancer risk and dietary intake of the carotenoids beta-carotene and lycopene and their major plant food sources, including carrots, green leafy vegetables, and tomato-based foods. The study was carried out in Auckland, New Zealand, during 1996-1997 and recruited 317 prostate cancer cases and 480 controls. The authors found that dietary intake of beta-carotene and its main vegetable sources was largely unassociated with prostate cancer risk, whereas intake of lycopene and tomato-based foods was weakly associated with a reduced risk. These results suggest that in contrast to the findings regarding many types of cancers, vegetables rich in beta-carotene are not protective against prostate cancer. However, lycopene from tomato-based foods was found to be associated with a small reduction in risk.  相似文献   
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