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Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
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Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
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A survey of 2576 children aged two to nine years was carried out in Dhaka, Bangladesh, as part of a collaborative study to test the validity of a questionnaire (the Ten Questions) for screening severe childhood disabilities in community settings. Approximately 7% of the children were positive on the screen and this rate was slightly higher in boys than girls. The sensitivity, specificity and negative predictive value of the Ten Questions were perfect or nearly perfect for severe and moderate (serious) disabilities. The positive predictive value was only 22% for serious disabilities, but 70% of children classified as false positives were found to have mild disabilities or other conditions (such as ear infections) for which early detection and treatment could be beneficial. No major age or gender differences in the validity of the questionnaire were apparent, but this finding needs additional study and confirmation with studies based on larger samples. In general, the results indicate that the Ten Questions is a valid tool for screening serious disabilities in children and can potentially improve the efficiency of health services by reducing the number of children requiring attention from professionals. Future studies using the Ten Questions should foster greater attention to the dimensions of childhood disability as a public health problem in the less developed world.  相似文献   
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OBJECTIVES. This study evaluated the effectiveness of a community coalition to prevent severe injuries to children in Central Harlem, New York, NY. It was hypothesized that injury incidence rates would decline during the intervention (1989 through 1991) relative to preintervention years (1983 through 1988); that the decline would be greatest for the targeted age group (5 through 16 years) and targeted injury causes (traffic accidents, assaults, firearms, outdoor falls); and that the decline would occur in the intervention community rather than a control community. METHODS. Surveillance of injuries that result in hospitalization and/or death among children in the two communities has been under way since 1983. Data from this surveillance were used to test whether the incidence of severe injury declined during the intervention; other temporal variations were controlled by Poisson regression. RESULTS. The incidence of injury among school-aged children in central Harlem declined during the intervention. The decline was specific to the targeted age group and targeted causes. A nonspecific decline also occurred in the control community. CONCLUSIONS. The declining incidence rate in Central Harlem is consistent with a favorable program effect, but additional investigation of possible secular trend or spillover effects is needed.  相似文献   
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Studies predict a 50 percent increase in residential long-term care need by the year 2000. Statistics show that the age group served by these facilities is at a much higher risk for sight threatening eye conditions. A review of the current literature as well as original data collected in Ohio indicates that residents in long-term care facilities are underserved with regard to eye care. This paper discusses the need for increased optometric participation in the primary eye care services for residents of long-term care facilities.  相似文献   
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There has been widespread use of periodic dilatations in the management of subglottic stenosis. However, some authorities have questioned the value in the overall rehabilitation of patients affected by this disorder. The first phase of this study included fourteen large dogs in which acute subglottic lesions were created by use of a high-speed electric drill and electrocautery. Twelve animals served as the experimental group and two animals were controls. Obstructing lesions developed in all the animals within 7 to 21 days. When at least a 50% obstruction developed in an animal, a treatment plan was instituted that included at least weekly dilatation, removal of granulations, and administration of intralesional steroids and/or systemic steroids and antibiotics. The two control animals became totally obstructed and were killed. Varying degrees of subglottic stenosis developed in all twelve experimental animals after 8 weeks of dilatation, but none required a tracheotomy. These twelve animals were then subjected to 8 additional weeks of dilatation and antibiotics, and supplemental steroids were used in some animals from this study. It can be concluded that early periodic dilatation and granulation removal in the acutely injured subglottis is effective in prevention of severe stenosis, late periodic dilatations in chronic subglottic stenosis are not helpful in further alleviation of obstruction, the concomitant use of antibiotics and systemic steroids did not appreciably prevent or alter the development of subglottic stenosis, and the concomitant use of intralesional steroids appeared to be of benefit in the management of chronic acquired subglottic stenosis.  相似文献   
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Characterization of the mitogenic signal from an oncogene ras protein   总被引:1,自引:0,他引:1  
Wild-type or cellular RAS proteins function at the end of the G1 phase of the cell cycle, but they cannot signal quiescent cells to start cycling. By contrast, the oncogenic or "activated" RAS proteins produced by certain mutant ras genes can start quiescent cells cycling and appear to be involved in a large fraction of human cancers. One of these "activated" RAS proteins is the temperature-sensitive viral K-RAS protein produced by tsKSV-NRK rat kidney fibroblasts. Reactivating this viral K-RAS protein in serum-starved quiescent cells by lowering the temperature from a non-permissive 41 degrees C to a permissive 36 degrees C is a powerful mitogenic signal which starts the progression of cells through the various stages of the cell cycle even in the absence of serum growth factors. This first signal is associated with transient surges of cytosolic Ca2+ and membrane-associated protein kinase C activity, but is not mediated by signals from the protein-tyrosine kinase receptors of known K-RAS-induced autocrine mitogens such as TGF alpha and PDGF. While the importance of the Ca2+ transient is uncertain, the transient surge of membrane-associated protein kinase C activity appears to be involved in the process by which the viral RAS protein triggers the G0 to G1 transition. The need for the viral K-RAS protein does not end with this first signal. The protein also operates briefly at the end of the G1 phase and then, after chromosome replication, it also stimulates events necessary for the initiation of mitosis.  相似文献   
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