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931.
The outcome of allogeneic hematopoietic stem cell transplantation (HCT) in patients with myeloid malignancies is better in those without minimal residual disease (MRD) than in those with MRD+,?as assessed by multiparametric flow cytometry (MPFC). WT1 quantitation also has been used to assess the probability of relapse in acute myelogenous leukemia (AML) treated with chemotherapy. We analyzed the clinical value of normalized bone marrow WT1 levels as a measure of the expanded myeloid progenitor compartment in a consecutive series of 193 adult patients with myeloid malignancies who underwent HCT. Bone marrow WT1 levels before the HCT, at the first bone marrow aspirate after infusion, and in the follow-up samples after HCT were determined by means of real-time PCR using the European LeukemiaNet normalized method. We sought to clarify the prognostic relevance in terms of overall survival (OS), progression-free survival (PFS), and cumulative incidence of relapse (CIR). Based on earlier experience in AML, we selected a threshold of 100 copies, defining 2 groups: patients with <100 WT1 copies and those with ≥100 copies. Patients with <100 WT1 copies before HCT (median time, 36 days; range, 4 to 268 days) had a better OS, PFS, and CIR than those with ≥100 copies (40?±?1 versus 29?±?6 days, P = .004; 35?±?9 versus 26?±?6 days, P = .002; and 29?±?7 versus 37?±?6 days, P = .051). In the first bone marrow study after the HCT (median time, 42 days; range 14 to 157 days, respectively), patients with <100 WT1 copies also had better outcomes in terms of OS, PFS, and CIR (40?±?7 versus 31?±?9 days, P = .025; 36?±?7 versus 30?±?8 days, P = .004; and 29?±?6 days versus 54?±?9, P?<?.001, respectively). At this time point, bone marrrow samples with >100 copies also included patients who were negative for MRD as assessed by MPFC (19 of 32). During the HCT follow-up, patients with sustained WT1 levels <100 copies showed a marked benefit in terms of OS, PFS, and CIR even compared with those with only a single measurement >100 copies (mean, 68?±?11 versus 26?±?7 days, P?<?.001; 63?±?11 versus 20?±?8 days, P?<?.001; and 20?±?8 vs. 71?±?8 days, P?<?.001, respectively). Standardized bone marrow WT1 levels using a 100-copy threshold in samples obtained before HCT, at leukocyte recovery, and during follow-up provided relevant prognostic information in patients with myeloid malignacies submitted to HCT.  相似文献   
932.

Purpose

In both structural and functional MRI, there is a need for accurate and reliable automatic segmentation of brain regions. Inconsistent segmentation reduces sensitivity and may bias results in clinical studies. The current study compares the performance of publicly available segmentation tools and their impact on diffusion quantification, emphasizing the importance of using recently developed segmentation algorithms and imaging techniques.

Methods

Four publicly available, automatic segmentation methods (volBrain, FSL, FreeSurfer and SPM) are compared to manual segmentation of the thalamus and hippocampus imaged with a recently proposed T1-weighted MRI sequence (MP2RAGE). We evaluate morphometric accuracy on 22 healthy subjects and impact on diffusivity measurements obtained from aligned diffusion-weighted images on a subset of 10 subjects.

Results

Compared to manual segmentation, the highest Dice similarity index of the thalamus is obtained with volBrain using a local library (\(M=0.913\), \(\hbox {SD}=0.014\)) followed by volBrain using an external library (\(M=0.868\), \(\hbox {SD}=0.024\)), FSL (\({M}=0.806\), \(\mathrm{SD}=0.034\)), FreeSurfer (\({M}=0.798\), \(\mathrm{SD}=0.049\)) and SPM (\({M}=0.787\), \(\mathrm{SD}=0.031\)). The same order is found for hippocampus with volBrain local (\({M}=0.892\), \(\mathrm{SD}=0.016\)), volBrain external (\({M}=0.859\), \(\mathrm{SD}=0.014\)), FSL (\({M}=0.808\), \(\mathrm{SD}=0.017\)), FreeSurfer (\({M}=0.771\), \(\mathrm{SD}=0.023\)) and SPM (\({M}=0.735\), \(\mathrm{SD}=0.038\)). For diffusivity measurements, volBrain provides values closest to those obtained from manual segmentations. volBrain is the only method where FA values do not differ significantly from manual segmentation of the thalamus.

Conclusions

Overall we find that volBrain is superior in thalamus and hippocampus segmentation compared to FSL, FreeSurfer and SPM. Furthermore, the choice of segmentation technique and training library affects quantitative results from diffusivity measures in thalamus and hippocampus.
  相似文献   
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Harm reduction is part of a comprehensive approach to dealing with the harms of drug use. Although the evidence to support implementation of harm reduction strategies for illicit drug use is abundant, it is unlikely that scientific knowledge alone will be enough to facilitate the adoption of harm reduction strategies in many health-care settings. The authors examine the ethical, legal and social context of harm reduction as it pertains to illicit drug use to assist nurses in providing safe, competent and ethical care. Included is an examination of values and accompanying responsibility statements from the Canadian Nurses Association's Code of Ethics for Registered Nurses that can guide nurses in their ethical reflection and provide insights into ethical practice.  相似文献   
935.

Objective

The overall therapeutic goal of venoarterial extracorporeal membrane oxygenation (ECMO) in patients with postcardiotomy shock is bridging to myocardial recovery. However, in patients with irreversible myocardial damage prolonged ECMO treatment would cause a delay or even withholding of further permanent potentially life-saving therapeutic options. We therefore assessed the prognostic effect of duration of ECMO support on survival in adult patients after cardiovascular surgery.

Methods

We enrolled into our single-center registry a total of 354 patients who underwent venoarterial ECMO support after cardiovascular surgery at a university-affiliated tertiary care center.

Results

Through a median follow-up period of 45 months (interquartile range, 20-81 months), 245 patients (69%) died. We observed an increase in mortality with increasing duration of ECMO support. The association between increased duration of ECMO support and mortality persisted in patients who survived ECMO support with a crude hazard ratio of 1.96 (95% confidence interval, 1.40-2.74; P < .001) for 2-year mortality compared with the third tertile and the second tertile of ECMO duration. This effect was even more pronounced after multivariate adjustment using a bootstrap-selected confounder model with an adjusted hazard ratio of 2.30 (95% confidence interval, 1.52-3.48; P < .001) for 2-year long-term mortality.

Conclusions

Prolonged venoarterial ECMO support is associated with poor outcome in adult patients after cardiovascular surgery. Our data suggest reevaluation of therapeutic strategies after 7 days of ECMO support because mortality disproportionally increases afterward.  相似文献   
936.

Purpose

Hirschsprung's disease (HD) is uncommon in females. There are very few reports on the patients' obstetric and gynecological outcome. Hydrosalpinx causes pain and infertility. It is rare in nonsexually active teenagers. It may be because of an intrinsic disease of the fallopian tubes or secondary to surgery. Aim: to describe the relationship between hydrosalpinx and HD or its surgical approach; to report the impact of bilateral hydrosalpinx on fertility in HD.

Methods

The records of all females with HD since 1980 were reviewed. Only patients who reached menarche were included. Prevalence of hydrosalpinx and hydrosalpinx-free survival were compared after abdominoperineal (A) or transanal (T) surgery. Treatment for hydrosalpinx was reviewed.

Results

Seventeen out of 27 patients had reached menarche (Group A: 13 patients; Group T: 4 patients). Five patients in group A and none in group T presented bilateral hydrosalpinx (p = 0.261). There were no statistical differences in hydrosalpinx-free survival between groups (p = 0.344). Hydrosalpinx treatment: two bilateral and one unilateral salpingectomy, one pyosalpinx evacuation and one untreated. Three patients had conception desire: one has children; two are on IVF program.

Conclusion

An association between hydrosalpinx and HD was observed. The development of hydrosalpinx was not associated with surgical approach in our study. Females with HD should have a gynecological follow-up for the development of hydrosalpinx, which can impair fertility.

Level of evidence

Level III, retrospective comparative study.  相似文献   
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