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101.
EN Smit JM Dijkstra TA Schnater E Seerat FAJ Muskiet ER Boersma 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(7):690-695
Abstract Erythrocyte fatty acids and plasma vitamin E concentrations were determined in 47 grade 2 and 21 grade 3 malnourished Pakistani children (ages 4–56 months). Data were compared with those of 26 age- and sex-matched apparently healthy controls. Evaluation with three statistical approaches revealed that both grade 2 and grade 3 malnourished children had decreased erythrocyte ω6 fatty acids and to a lesser extent decreased ω3 fatty acids. These decreases were compensated for by increased ω9 fatty acids. The patients tended to have lower plasma vitamin E concentrations. We conclude that malnourished Pakistani children have low essential fatty acid status, notably those of the ω6 series. The combination of low erythrocyte 22:6ω3 and a low 22:5ω6/22:4ω6 ratio in grade 2 patients suggests low Δ4-desaturation activity, which may be due to impaired peroxisomal β-oxidation. 相似文献
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The aim of this work was to study the influence of bacterial cell concentrations and inorganic anions on lysis of Streptococcus mutans BHT by human salivary lysozyme (HSL). HSL was partly purified from saliva by ion exchange chromatography. The bacteria were grown in a synthetic medium containing 3H-thymidine to monitor DNA release. The experiments demonstrated that release 3H-thymidine was dependent on the bacterial cell concentration and an apparent Km-value corresponding to approximately 2.9 × 108 cells/ml was calculated. The influence of I?, Br?, Cl?, F?, HCO3? and SCN? on bacteriolysis was studied. All anions tested were slightly inhibitory on the action of HSL. The inhibition varied from 7 to 76% depending on the ion and ionic strength. The order of addition of HSL and sodium chloride caused different lytic responses. This was reflected by the amount of HSL adsorbed by the bacteria. 相似文献
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108.
MP Busch ; EA Operskalski ; JW Mosley ; CE Stevens ; ER Schiff ; SH Kleinman ; H Lee ; M Lee ; M Harris 《Transfusion》1994,34(10):858-864
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts. 相似文献
109.
Bergmann MA Murphy KM Kiely DK Jones RN Marcantonio ER 《Journal of the American Geriatrics Society》2005,53(10):1817-1825
Although delirium has been shown to be a common, morbid, and costly problem for hospitalized older people, evidence has mounted that it may persist for weeks or months. Therefore, concern about delirium can no longer be confined to acute care. After an acute hospitalization, many older people are discharged to postacute care (PAC) facilities--rehabilitation hospitals and skilled nursing facilities. Although several models designed to prevent delirium in the hospital setting have been described, there have been few such efforts in the PAC setting. This article describes the development of a multifactorial delirium abatement program (DAP), a new model of care for older patients admitted to the postacute skilled nursing facility with delirium. The DAP is a nurse-led, unit-based intervention. The program consists of four modules based on best practices as defined by the peer-reviewed literature: standardized screening for symptoms and signs of delirium upon admission to the PAC unit, assessment and treatment of possible causes of and contributors to delirium, prevention and management of common delirium complications, and restoration of patient cognitive and self-care function. This article also presents the process of facility introduction, staff education on DAP content, and multidisciplinary outreach. Key strategies for DAP implementation are reviewed. Program adoption challenges and corresponding model refinements to enhance adherence and overall care quality are highlighted. Last, clinical adaptation of this research-derived program is discussed. 相似文献
110.
Schwartz-Filho HO Morandini AC Ramos-Junior ES Jimbo R Santos CF Marcantonio E Wennerberg A Marcantonio RA 《Journal of biomedical materials research. Part A》2012,100(10):2629-2636
Implant topography is an important factor that influences many cell types. To understand the role of topography in the inflammatory events, we evaluated the response of human gingival fibroblasts (HGFs) by the release pattern of cytokines. HGFs were cultured on Ti discs for 24 and 48 h. Four different surface treatments were used: machining method (turned), blasting followed by an acid-etching method (BAE), oxidative nanopatterning (ON) method, and an association of blasting followed by an acid-etching plus oxidative nanopatterning (BAE+ON) method. Extracellular levels of IL-6, IL-8, transforming growth factor beta (TGF-β), IL-4, and IL-10 were measured by enzyme-linked immunosorbant assay. Increased levels of IL-6 and IL-8 were observed in all surfaces after 24 h which decreased after 48 h. BAE, ON, and BAE+ON surfaces showed a reduction in IL-6 levels compared with the turned after 48 h (p < 0.05). On one hand, IL-8 production was lower in BAE+ON in comparison to the turned surface (p < 0.05). On the other hand, IL-4 showed increased levels with 48 h, which were significantly different between turned, BAE, and ON surfaces, but not with BAE+ON. Additionally, TGF-β and IL-10 production were not detected. This study indicates that nanotopography might be important in the modulation of the inflammatory response in cultured HGFs. ? 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A:2629-2636, 2012. 相似文献