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991.
Development and behaviour at five years were assessed in children from a national cohort; comparisons were drawn between those living in one-parent families, in step-parent families and with both natural parents. On average, children from one-parent families scored worst and children from two-parent families best on tests of behaviour, vocabulary and visuomotor co-ordination. The differences remained significant after allowing for associated influences. The behaviour of children from one-parent families and step-parent families was perceived on average as more 'anti-social' than that of children from two-parent families. Children in one-parent families were seen on average as marginally more 'neurotic' than children in two-parent families.  相似文献   
992.
A rapid bioassay procedure is described for quality-control testing water and apparatus used in the preparation of media for gamete and embryo culture. This bioassay is based on the sensitivity of hamster epididymal spermatozoa to contaminants present in water and/or in the culture apparatus. The bioassay is usually performed using a modified Tyrode's solution as the sperm culture medium, although complex media can be used. The sensitivity of this test is greatly enhanced by the absence of protein in the medium. The bioassay has been used to detect impurities in water prepared by a standard cartridge filtration system and to verify that reverse-osmosis pretreatment of water could eliminate the problem. It has also detected toxic contaminants leached from syringe filters during medium sterilization. The bioassay is simple to perform and can be completed in 1 working day. It may be a useful alternative to the conventional mouse embryo tests that are in widespread use in human in vitro fertilization (IVF) laboratories.  相似文献   
993.
This paper reviews the incidence and pathology of liver tumours in children in the State of Victoria from 1955 to 1987. Seventy-four cases were found and are believed to represent all liver tumours in the State during that time. There were 29 benign and 45 malignant tumours. The benign tumours comprised 13 haemangiomas, 12 mesenchymal hamartomas, and 4 epithelial lesions. The malignant tumours were 30 hepatoblastomas, 8 embryonal sarcomas, 4 hepatocellular carcinomas, and 3 miscellaneous tumours. The haemangiomas were more commonly cavernous. Four were associated with skin lesions and 3 of these were capillary in type. Mesenchymal hamartomas varied from predominantly solid to predominantly cystic. All, however, contained hamartomatous collections of ducts and liver cells irregularly arranged in dense fibrous tissue. The commonest malignant tumour was hepatoblastoma, and there were 15 of predominantly epithelial type and 15 of mixed epithelial and mesenchymal type. The 8 undifferentiated sarcomas of embryonal pattern were characterised by pleomorphism of cells, bizarre giant cells, and extensive mucoid stromal change. Four examples of hepatocellular carcinoma were seen. All were multifocal and no further case has been seen for the last 15 years. The 3 miscellaneous tumours were gastrinoma, rhabdoid tumour, and myofibroblastic tumour of uncertain histogenesis. Incidence was calculated for the period of review. The rate for benign tumours was 0.81 per million children per year and for malignant tumours 1.33 per million children per year. Surgery for hepatobalstoma was shown to be the most important factor in improving survival.  相似文献   
994.
THE SALIENCE OF FACIAL EXPRESSION FOR AUTISTIC CHILDREN   总被引:9,自引:0,他引:9  
Autistic and non-autistic retarded children who were matched for verbal ability were shown 'standard' pairs of photographs of people who differed in three, two or one of the following respects: sex, age, facial expression of emotion, and the type of hat they were wearing. When given similar photographs to sort, the majority of non-autistic children sorted according to people's facial expressions before they sorted according to type of hat, but most autistic children gave priority to sorting by type of hat, and many neglected the facial expressions altogether. It is suggested that these results reflect autistic children's insensitivity to other people's facial expressions of emotion.  相似文献   
995.
TEENAGE MOTHERING: CHILD DEVELOPMENT AT FIVE YEARS   总被引:1,自引:0,他引:1  
Developmental outcome at 5 yr was compared in 1031 singleton children of teenage mothers and 10,950 singleton children of older mothers in a national longitudinal study. Children born to teenage mothers and living with them through the first 5 yr performed less well than other children in tests of vocabulary and behaviour at 5 yr of age; they were also shorter on average and had a smaller head circumference. These differences remained significant after allowing for certain social and biological factors, whereas a difference on visuomotor coordination did not. Teenage mothering thus appears somewhat disadvantageous to children's development.  相似文献   
996.
SUMMARY: To evaluate and compare thin section CT scans (TSS) and minimum intensity projection images (MinIPs) in healthy individuals, 10 nonsmokers with normal pulmonary function tests were studied using ten 1-mm collimated, helically acquired TSS images after full inspiration and expiration at two anatomic levels. Ten-millimeter-thick MinIPs were generated from the helical scans. Two thoracic radiologists compared TSS and MinIPs for artifacts and air trapping. Hounsfield unit (HU) measurements of TSS and MinIPs were obtained. The lung parenchyma on MinIPs demonstrates a smooth anterior-to-posterior attenuation gradient, accentuated by expiration. Motion and beam-hardening artifacts on TSS images resulted in regions of high and low attenuation on MinIPs, respectively. Expiratory TSS and MinIPs demonstrated air trapping (n = 31/40; range, 0-25%; mean, 7.2%). In comparison with TSS, MinIPs improved the conspicuity of air trapping (n = 20) and appeared to detect more air trapping (n = 7). No statistical differences were found when comparing the mean HU values of TSS and MinIPs. MinIPs demonstrated a smooth anterior-to-posterior attenuation gradient. Compared with TSS, MinIPs improve the conspicuity of air trapping in healthy individuals. Therefore, expiratory MinIPs may be useful in detecting air trapping as a result of disease.  相似文献   
997.
Summary : The objective was to determine whether diffuse damage to orbital and ventromedial regions of the prefrontal cortex usually associated with moderate-to-severe closed head injury (CHI) would affect the ability to perceive and respond to socially relevant information.

Methods : Participants with CHI and age-matched non-injured controls were presented with faces that varied with respect to emotional expression while electrodermal activity (EDA) was monitored. Cognitive and general adaptive functioning was also assessed.

Results : CHI was associated with a failure to increase EDA in response to negative facial expressions and with reduced ability to identify negative expressions, especially fear. The groups differed on other signs of orbital/medial prefrontal damage such as anosmia and in general social adaptability and awareness-of-deficit as measured by the Brock Adaptive Functioning Questionnaire.

Conclusions : CHI affected the ability to identify and respond to negative facial expression. Addressing these deficits may enhance rehabilitative efforts within the social domain.  相似文献   
998.
999.
We report an unusual case of a patient with diminished cardiac output caused by systemic venous occlusions of unclear etiology with a history of idiopathic fibrosing mediastinitis and retroperitoneal fibrosis. On thoracic, abdominal, and pelvic venograms, the patient was previously known to have superior vena caval and infrarenal inferior vena caval occlusions. Subsequent studies revealed retrograde flow through the azygous and hemiazygous veins and numerous caval-portal anastomoses providing venous return from the upper and lower extremities. After an extensive hypercoagulable state work-up, no abnormalities were found. To relieve the symptoms, the patient underwent an elective right thoracotomy with azygous vein to right atrial bypass graft. The patient has had complete amelioration of the disabling symptoms and participates in many activities that he could not tolerate previously. Because this condition and procedure are unreported, we present a novel surgical treatment option to palliate symptoms caused by concurrent superior and inferior caval obstructions by improving venous return to the heart.  相似文献   
1000.
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