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81.
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This retrospective study compared clinical, radiological and subjective outcomes between patients with a distal radius fracture fixed with a variable angle or fixed angle volar locking plate. Radiological parameters were assessed between initial and final post-operative films. Post-operative clinical range of motion as a proportion of that in the opposite wrist was assessed clinically, and satisfaction and subjective outcomes were assessed by questionnaire. One hundred and seven patients were included in the study; 65 underwent fixation with a variable angle and 42 with a fixed angle locking plate. There were five complications and secondary operations in each group. There was no significant difference between the groups in radiological parameters measured or the proportional range of motion. Visual analogue scale, Mayo Wrist and Quick DASH scores were not significantly different between the groups. Neither the subjective nor clinical outcomes of this study demonstrated clinical superiority of either plate system.  相似文献   
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In this work, Cu2WS4 nanoparticles have been synthesized via a solvothermal decomposition approach using a heterobimetallic single source precursor, WCu2S4(PPh3)3. The single source precursor, WCu2S4(PPh3)3, has been characterized using multinuclear NMR spectroscopy, while Cu2WS4 nanoparticles have been characterized by powder X-ray diffraction (PXRD) for which Rietveld refinement has been performed to authenticate the lattice structure of the decomposed product, Cu2WS4. Furthermore, FESEM and EDAX analyses have been performed to assess the morphology and composition of Cu2WS4. An electrochemical study in acidic as well as basic media suggested that Cu2WS4 nanoparticles possess efficient bifunctional activity towards electrochemical hydrogen as well as oxygen evolution reactions. Linear sweep voltammetry (LSV) performed in 0.5 N H2SO4 indicates an onset potential for the HER of 462 mV and a Tafel slope of 140 mV dec−1. While LSV performed in 0.1 M KOH indicates an onset potential for the OER of 190 mV and a Tafel Slope of 117 mV dec−1.  相似文献   
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Background:Barriers to colorectal cancer screening persist despite screening campaigns, especially among women. This study explores the prevalence, preferences, and barriers associated with colorectal cancer screening and evaluates the effect of an inpatient intervention (one-on-one bedside education and handout about colorectal cancer) on screening adherence among hospitalized women.Methods:A prospective intervention study among 510 hospitalized women, who are cancer-free (except for skin cancer) at enrollment, aged between 50 and 75 years was conducted at an academic center. Socio-demographic, family history, and medical comorbidities data were collected for all patients. A post-hospitalization follow-up survey determined the effect of inpatient intervention on colorectal cancer screening adherence. Unpaired t-test and chi-square tests were used to compare characteristics, perspectives, and preferences for screening among adherent and non-adherent groups.Results:Mean age was 60.5 years, 45% reported an annual household income of <$20 000, 36% of women were African American, 27% of women were overdue for colorectal cancer screening, and 33% never had a screening colonoscopy. The most frequently reported barriers to colorectal cancer screening were “I have other problems more important than getting a colonoscopy,” “No transportation to get to the test,” and “Not counseled by primary care provider.” Sixty-six percent of the non-adherent women would agree to have an inpatient screening colonoscopy if offered.Conclusion:A significant number of hospitalized women are non-adherent to colorectal cancer screening, while the educational intervention was partially successful in enhancing colorectal cancer screening, most hospitalized women remained non-adherent after hospitalization. A majority of these women were amenable to inpatient screening colonoscopy if offered during a hospital stay.  相似文献   
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The mechanisms of uptake and transcellular passage of dextromethorphan (DM) and its major metabolite dextrorphan (DX) across the endothelial component of the blood-brain barrier have been investigated with primary cultures of bovine brain microvessel endothelial cells (BMECs). The uptake of [14C]DM and [14C]DX by BMECs was observed to be temperature-sensitive and saturable, with approximate Km's of 0.12 and 0.29 mM and Vmax's of 9.2 and 11.0 pmol/mg/min, respectively. The BMEC uptake of [14C] DM was inhibited half-maximally by approximately 0.57 mM L-glutamic acid, 0.71 mM N-methyl-d-asparatate (NMDA), and 0.99 mM DL-threo-β-hydroxyaspartic acid. The BMEC uptake of [14C]DX was inhibited half-maximally by approximately 0.48 mM L-glutamic acid, 1.50 mM NMDA, and 0.69 mM DL-threo-β-hydroxyaspartic acid. Conversely, the bidirectional passage of DM and DX across confluent BMEC monolayers occurred at a faster rate but was neither saturable nor inhibited by high concentrations of glutamic acid, NMDA, or unlabeled DM or DX. These results suggest that DM and DX are capable of interacting with a low-capacity glutamic acid-type carrier mechanism on the apical surface of BMECs. However, the net transfer of these agents across BMEC monolayers appeared to be more rapid and passive in nature.  相似文献   
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BACKGROUND: Genetic variation in DNA repair may contribute to differences in the susceptibility of several cancers. We evaluated two polymorphisms in the base excision repair pathway (BER) (XRCC1; Arg194Trp and Arg399Gln) and one polymorphism in the double strand DNA repair pathway (XRCC3; Thr241Met) for their association with breast cancer risk. METHODS: The association was analyzed in a nested case control study of 460 breast cancer cases and 324 cancer-free controls within the Iowa Women's Health Cohort. DNA was obtained from blood samples or paraffin embedded tissues (PET) and all samples were genotyped by one of three genotyping platforms-PCR-RFLP, PCR-INVADER, or Sequenom. RESULTS: None of the three polymorphisms studied were significantly associated with breast cancer risk (XRCC1: Arg194Trp (OR=1.21, 95% CI: 0.78-1.88); Arg399Gln (OR=1.20, 95% CI: 0.80-1.79); XRCC3: Thr241Met (OR=1.04, 95% CI: 0.76-1.41). CONCLUSIONS: These results suggest that independently these polymorphisms of XRCC1 and XRCC3 genes do not contribute significantly to the genetic susceptibility of breast cancer.  相似文献   
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Similar retinitis pigmentosa (RP) phenotypes can result from mutations affecting different rhodopsin regions, and distinct amino acid substitutions can cause different RP severity and progression rates. Specifically, both the R135L and R135W mutations (cytoplasmic end of H3) result in diffuse, severe disease (class A), but R135W causes more severe and more rapidly progressive RP than R135L. The P180A and G188R mutations (second intradiscal loop) exhibit a mild phenotype with regional variability (class B1) and diffuse disease of moderate severity (class B2), respectively. Computational and in vitro studies of these mutants provide molecular insights into this phenotypic variability.  相似文献   
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