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101.
Triple-balloon dilation (TBD) of a variety of luminal structures has been successfully, though infrequently, used. A mathematical model is presented for the selection of balloon sizes, and equations and tables are derived that allow the user to estimate more accurately the size of balloons needed for TBD of structures with large lumina. With TBD, an approximately circular lumen can be formed. Also, TBD allows smaller, higher-pressure balloons to be used instead of single, low-pressure, large balloons. However, multiple puncture sites may be required for TBD.  相似文献   
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OBJECTIVE: Greater availability and utilization of modern radiological imaging modalities have resulted in an increase in the incidental discovery of renal cell carcinoma. Such tumours tend to be smaller than their symptomatic counterparts and may potentially be adequately treated using nephron-sparing surgery. METHODS: A retrospective review of all patients who were diagnosed with renal cell carcinoma of 4 cm or less between January 1990 and December 2001 was conducted to review clinical presentation, surgical management and survival. RESULTS: The cohort comprised 102 patients who underwent surgery, of 402 patients diagnosed with renal cell carcinoma over the study period. Sixty-eight patients (67%) had tumours detected incidentally. Thirty patients (29%) were managed with partial nephrectomy and 72 (71%) with radical nephrectomy. The median tumour size was 3.0 cm (range, 1.5-4.0 cm). Overall, median follow-up was 60 months (range, 1-148 months). Overall 5-year survival for patients who underwent partial nephrectomy and radical nephrectomy was 96.6% and 85.8%, respectively. Cancer-specific 5-year survival was 100%. CONCLUSION: A significant proportion of patients had incidental diagnosis of small renal cell carcinoma. Local control may be achieved with either radical or partial nephrectomy, with excellent survival expected.  相似文献   
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Background

Internet interventions with and without therapist support have been found to be effective treatment options for harmful alcohol users. Internet-based therapy (IT) leads to larger and longer-lasting positive effects than Internet-based self-help (IS), but it is also more costly to provide.

Objective

To evaluate the cost effectiveness and cost utility of Internet-based interventions for harmful use of alcohol through the assessment of the incremental cost effectiveness of IT compared with IS.

Methods

This study was performed in a substance abuse treatment center in Amsterdam, the Netherlands. We collected data over the years 2008–2009. A total of 136 participants were included, 70 (51%) were female, and mean age was 41.5 (SD 9.83) years. Reported alcohol consumption and Alcohol Use Disorders Identification Test (AUDIT) scores indicated harmful drinking behavior at baseline. We collected self-reported outcome data prospectively at baseline and 6 months after randomization. Cost data were extracted from the treatment center’s cost records, and sex- and age-specific mean productivity cost data for the Netherlands.

Results

The median incremental cost-effectiveness ratio was estimated at €3683 per additional treatment responder and €14,710 per quality-adjusted life-year (QALY) gained. At a willingness to pay €20,000 for 1 additional QALY, IT had a 60% likelihood of being more cost effective than IS. Sensitivity analyses attested to the robustness of the findings.

Conclusions

IT offers better value for money than IS and might therefore be considered as a treatment option, either as first-line treatment in a matched-care approach or as a second-line treatment in the context of a stepped-care approach.

Trial Registration

Netherlands Trial Register NTR-TC1155; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1155 (Archived by WebCite at http://www.webcitation.org/6AqnV4eTU)  相似文献   
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AIMS: In several observational studies, revascularization is associated with substantial reduction in mortality in patients with non-ST-segment elevation acute coronary syndrome (nSTE-ACS). This has strengthened the belief that routine early angiography would lead to a reduction in mortality. We investigated the association between actual in-hospital revascularization and long-term outcome in patients with nSTE-ACS included in the ICTUS trial. METHODS AND RESULTS: The study population of the present analysis consists of ICTUS participants who were discharged alive after initial hospitalization. The ICTUS trial was a randomized, controlled trial in which 1200 patients were randomized to an early invasive or selective invasive strategy. The endpoints were death from hospital discharge until 4 year follow-up and death or spontaneous myocardial infarction (MI) until 3 years. Among 1189 patients discharged alive, 691 (58%) underwent revascularization during initial hospitalization. In multivariable Cox regression analyses, in-hospital revascularization was independently associated with a reduction in 4 year mortality and 3 year event rate of death or spontaneous MI: hazard ratio (HR) 0.59 [95% confidence interval (CI) 0.37-0.96] and 0.46 (95% CI 0.31-0.68). However, when intention-to-treat analysis was performed, no differences in cumulative event rates were observed between the early invasive and selective invasive strategies: HR 1.10 (95% CI 0.70-1.74) for death and 1.27 (95% CI 0.88-1.85) for death or spontaneous MI. CONCLUSION: The ICTUS trial did not show that an early invasive strategy resulted in a better outcome than a selective invasive strategy in patients with nSTE-ACS. However, similar to retrospective analyses from observational studies, actual revascularization was associated with lower mortality and fewer MI. Whether an early invasive strategy leads to a better outcome than a selective invasive strategy cannot be inferred from the observation that revascularized patients have a better prognosis in non-randomized studies.  相似文献   
110.

Background:

Solute carriers (SLCs), in particular organic cation transporters (OCTs), have been implicated in the cellular uptake of platinum-containing anticancer compounds. The activity of these carriers may determine the pharmacokinetics and the severity of side effects, including neuro- and nephrotoxicity of platinum-based chemotherapy. As decreased drug accumulation is a key mechanism of platinum resistance, SLCs may also contribute to the development of resistance. Here, we define the role of hSLC22A2 (OCT2) in the cellular uptake of platinum compounds.

Experimental approach:

Human embryonic kidney (HEK) 293 cells stably expressing the hSLC22A2 gene (HEK293/hSLC22A2) were used in platinum accumulation studies. Following a 2 h exposure to various platinum compounds (100 µM), intracellular platinum levels were determined by flameless atomic absorption spectrometry.

Key results:

HEK293/hSLC22A2 cells, compared with HEK293/Neo control cells, displayed significant increases in oxaliplatin (28.6-fold), Pt[DACH]Cl2 (20.6-fold), ormaplatin (8.1-fold), tetraplatin (4.5-fold), transplatin (3.7-fold) and cisplatin (1.3-fold), but not carboplatin. SLC22A2-mediated transport could be inhibited by 1-methyl-4-phenylpyridinium. Furthermore, hSLC22A2-mediated oxaliplatin and cisplatin accumulation was time- and concentration-dependent, but non-saturable. Expression of hSLC22A2 in HEK293 cells resulted in enhanced sensitivity to oxaliplatin (12-fold) and cisplatin (1.8-fold). Although, hSLC22A2 mRNA expression was frequently found in ovarian cancer cell lines, its expression in clinical ovarian cancer specimens (n= 80) was low and did not correlate with the treatment outcome of platinum-based regimens.

Conclusions and implications:

The hSLC22A2 drug transporter is a critical determinant in the uptake and cytotoxicity of various platinum compounds, particularly oxaliplatin.  相似文献   
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