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991.
We evaluated the performance of the Roche OnTrak Testcup-er (TC-er), an on-site drug-testing device, for the detection of amphetamines (AMP), barbiturates (BRB), benzodiazepines (BNZ), benzoylecgonine (BE), and opiates (OPI) in urine specimens from hospital emergency departments. This device utilizes a competitive binding microparticle immunoassay to simultaneously determine the presence of the following drugs or drug classes in urine at and above the following cut-off concentrations: AMP, 1000 ng/mL; BRB, 200 ng/mL; BNZ 200 ng/mL; BE, 300 ng/mL; and OPI, 300 ng/mL. One hundred forty-nine urine specimens received from emergency departments were simultaneously tested by the EMIT II monoclonal immunoassay (Emit) and TC-er. Specimens yielding discordant results were analyzed by gas chromatography-mass spectrometry. There was a 98% (146/149) agreement of results between the methods for the presence or absence of drugs. TC-er yielded 110 positive drug findings in 79 specimens, and Emit yielded 102 positive drug findings in 76 specimens. There was a 97% agreement between the methods for positive findings of at least one drug. The majority of discordant results were due to variations in selectivity of the assays for phenobarbital and BNZ metabolites. TC-er yielded a single false-positive result for amphetamines, and barbiturates, possibly three false-positive benzodiazepine results, and a single false-negative opiate finding. This represented four certain errors out of 745 total results, or a 0.4% error rate. If the three false-positive BNZ results were also considered, the error rate would be 0.9%. TC-er demonstrated acceptable linearity around the cut-off concentration of each drug. The TC-er was determined to be a reliable device for rapid on-site testing of emergency department urine specimens.  相似文献   
992.
BACKGROUND: The role of active and passive smoking in breast cancer remains controversial. METHODS: Using data collected in the prospective Nurses' Health Study, we examined the influence of active and passive smoking on the incidence of invasive breast cancer. The analysis was based on women responding to the 1982 questionnaire, which included questions on passive smoking exposure. Information on active smoking was collected in biennial questionnaires. A total of 78,206 women were followed prospectively from 1982 until June 1996. RESULTS: Of these women, 3,140 reported a diagnosis of invasive breast cancer during follow-up. Compared with never active smoking, relative risks (RR) of breast cancer were 1.04 (95% CI = 0.94-1.15) for current active smoking and 1.09 (95% CI = 1.00-1.18) for past active smoking. The RR for regular passive exposure at work and at home was 0.90 (95% CI = 0.67-1.22). For active smoking, a modest increase in risk was confined to women who began smoking before the age of 17 (RR = 1.19; 95% CI = 1.03-1.37). CONCLUSION: Results suggest that passive smoking is unrelated to breast cancer. However, results for active smoking are compatible with a small increase in risk when smoking is initiated at young ages.  相似文献   
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995.
The aim of the work is the evaluation of the microbial content of soft cheese when it comes on the table of the consumer. To reach this purpose we have bought, as simple clients, the product in the small and average distributions that apply the HACCP (Hazard Analysis Critical Control Point) plain and in the small distributions which don't apply it, the collecting and the microbiological analysis of the product has been performed on the different pieces that belong to the whole form of cheese during the days of the week, observing a progressive increase of the bacterial number; besides we have found in the bought cheese that when the form of cheese was at the end, values overcame the limits of law. The increase of the bacterial numbers was greater in the products purchased in the average distributions in order with the application of the self-control, and in the small ones that don't effect this type of selling. The deduction was that the HACCP system has not been correctly applied in all the shops tested and in the exercises without the HACCP plain the contamination levels are higher. The health risk connected with not correct manipulation by the employees still results very elevated.  相似文献   
996.
Population-based psychotherapy considers the provision of services to a population at risk for or already affected with a disease or disorder. Using existing data on prevalence, incidence, risk factors, and interventions (both preventive and clinical) for eating disorders (anorexia excluded), this article examines issues related to integrating and providing risk reduction and treatment to a population of female college students. Population-based psychotherapy models have important implications for the provision of services and for future directions in research on eating and other types of mental health disorders, but the assumptions need to be carefully examined. Studies that provide data combining population-based risk factor reduction and clinical treatment are needed to advance this field.  相似文献   
997.
Videoconferencing has been used to provide distance education for medical students, physicians and other health-care professionals, such as nurses, physiotherapists and pharmacists. The Dalhousie University Office of Continuing Medical Education (CME) has used videoconferencing for CME since a pilot project with four sites in 1995-6. Since that pilot project, videoconferencing activity has steadily increased; in the year 1999-2000, a total of 64 videoconferences were provided for 1059 learners in 37 sites. Videoconferencing has been well accepted by faculty staff and by learners, as it enables them to provide and receive CME without travelling long distances. The key components of the development of the videoconferencing programme include planning, scheduling, faculty support, technical support and evaluation. Evaluation enables the effect of videoconferencing on other CME activities, and costs, to be measured.  相似文献   
998.
P-glycoprotein (P-gp) functions as a drug efflux pump, mediating multidrug resistance and limiting the efficacy of many drugs. Clearly, identification of potential P-gp substrate liability early in the drug discovery process would be advantageous. We describe a multiple-pharmacophore model that can discriminate between substrates and nonsubstrates of P-gp with an accuracy of 63%. The application of this filter allows large virtual libraries to be screened efficiently for compounds less likely to be transported by P-gp.  相似文献   
999.
The reduction of caregiver burden for those caring for patients with Alzheimer's disease (AD) is especially important given the prevalence of AD as populations age. This paper reviews the complex nature of caregiver burden, how it is measured, and possible interventions that may affect caregiver burden. Caregiver characteristics as well as symptoms exhibited by patients contribute to burden. A number of specific quantitative measures which have been developed to better evaluate caregiver burden are discussed. Such measures are also useful in measuring the impact of interventions on caregiver burden. Pharmacological treatment of patients with AD through the use of acetylcholinesterase inhibitors has positively affected cognition, activities of daily living, and behavioural problems. These benefits significantly reduce caregiver burden. The same is true for psychosocial interventions for the caregiver. It has been suggested that combining both approaches should be utilised for optimal management. Our knowledge of caregiver burden has greatly increased over the past two decades with clear benefits for both patients and caregivers. However, many aspects still clearly require further research. Given the significance of caregiver burden, various aspects have been extensively studied including contributing and protective factors, quantitative assessment, and pharmacological and psychosocial intervention. It is important for clinicians to be aware of this knowledge so that they can effectively incorporate it into their treatment plans for those affected by AD.  相似文献   
1000.
Rationale for Ras and raf-kinase as a target for cancer therapeutics   总被引:2,自引:0,他引:2  
Improvements in our understanding of the intrinsic aberrancies in cancer cells have enabled the design and development of novel therapeutics that specifically target these changes. Among the many complex cellular pathways and mechanisms which have been unveiled by new molecular techniques, RAS-mediated signal transduction is one met with tremendous research interests. Activation of RAS initiates several signaling cascades, of which the RAS-RAF-MEK-ERK pathway is among the better delineated, and is the main focus of this review. Other cellular consequences of RAS activation including interactions with the RHO-family proteins, the PI3-kinase pathway, and other mitogen activated protein kinase cascades, will be discussed. The intricate balance and coordination of multiple RAS-mediated signals lead to ultimate effects on cell growth, differentiation, cycling and survival. Pharmacological strategies such as analog development, synthesis of small molecule inhibitors, antisense technology, and vaccine therapy have been utilized to intervene with key RAS-signaling proteins, in an attempt to provide rational therapeutic solutions in malignant diseases.  相似文献   
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