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11.

Introduction

The impact of the dose and fractionation of thoracic radiotherapy on the risk of developing brain metastasis (BM) has not been evaluated prospectively in limited stage SCLC patients receiving prophylactic cerebral irradiation (PCI).

Methods

Data from patients treated with PCI from the CONVERT trial were analyzed.

Results

Four hundred forty-nine of 547 patients (82%) received PCI after completion of chemoradiotherapy. Baseline brain imaging consisted of computed tomographic scans in 356 of 449 patients (79%) and magnetic resonance imaging in 83 of 449 (18%) patients. PCI was delivered to 220 of 273 participants (81%) in the twice-daily (BD) group and 229 of 270 in the once-daily (OD) group (85%; p = 0.49). Total median PCI dose was 25 Gy in both the BD and OD groups (p = 0.74). In patients who received PCI, 75 (17%) developed BM (35 [8%] in OD and 40 [9%] in BD) and 173 (39%) other extracranial progression. In the univariate analysis, gross tumor volume (GTV) was associated with an increased risk of BM (p = 0.007) or other radiological progression events (p = 0.006), whereas in a multivariate analysis both thoracic GTV (tGTV) and ECOG performance score were associated with either progression type. The median overall survival (OS) of patients treated with PCI was 29 months. In the univariate analysis of OS, PCI timing from end of chemotherapy, weight loss of more than 10%, and tGTV were prognostic factors associated with OS. In the multivariate analysis, only tGTV was associated with OS. Delay between end of chemotherapy and PCI was not associated with OS.

Conclusions

Patients receiving OD or BD thoracic radiotherapy have the same risk of developing BM. Larger tumors are associated with a higher risk of BM.  相似文献   
12.

Background

The definition of left ventricular (LV) non-compaction is controversial, and discriminating between normal and excessive LV trabeculation remains challenging. Our goal was to quantify LV trabeculation on cardiovascular magnetic resonance (CMR) images in a genetic mouse model of non-compaction using a dedicated semi-automatic software package and to compare our results to the histology used as a gold standard.

Methods

Adult mice with ventricular non-compaction were generated by conditional trabecular deletion of Nkx2–5. Thirteen mice (5 controls, 8 Nkx2–5 mutants) were included in the study. Cine CMR series were acquired in the mid LV short axis plane (resolution 0.086?×?0.086x1mm3) (11.75 T). In a sub set of 6 mice, 5 to 7 cine CMR were acquired in LV short axis to cover the whole LV with a lower resolution (0.172?×?0.172x1mm3). We used semi-automatic software to quantify the compacted mass (Mc), the trabeculated mass (Mt) and the percentage of trabeculation (Mt/Mc) on all cine acquisitions. After CMR all hearts were sliced along the short axis and stained with eosin, and histological LV contouring was performed manually, blinded from the CMR results, and Mt, Mc and Mt/Mc were quantified. Intra and interobserver reproducibility was evaluated by computing the intra class correlation coefficient (ICC).

Results

Whole heart acquisition showed no statistical significant difference between trabeculation measured at the basal, midventricular and apical parts of the LV. On the mid-LV cine CMR slice, the median Mt was 0.92 mg (range 0.07–2.56 mg), Mc was 12.24 mg (9.58–17.51 mg), Mt/Mc was 6.74% (0.66–17.33%). There was a strong correlation between CMR and the histology for Mt, Mc and Mt/ Mc with respectively: r2?=?0.94 (p?<?0.001), r2?=?0.91 (p?<?0.001), r2?=?0.83 (p?<?0.001). Intra- and interobserver reproducibility was 0.97 and 0.8 for Mt; 0.98 and 0.97 for Mc; 0.96 and 0.72 for Mt/Mc, respectively and significantly more trabeculation was observed in the Mc Mutant mice than the controls.

Conclusion

The proposed semi-automatic quantification software is accurate in comparison to the histology and reproducible in evaluating Mc, Mt and Mt/ Mc on cine CMR.
  相似文献   
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OBJECTIVE: Surgery is the treatment of reference for early-stage esophageal cancer, but 5-year survival is only 20% to 25%. After complete resection (R0), survival is significantly longer than after incomplete resection, with microscopic (R1) or macroscopic (R2) penetration. The purpose of this work was to identify retrospectively the factors predictive of complete resection of operable esophageal cancers.PATIENTS AND METHODS: Between January 1982 and March 2001, 746 patients with esophageal cancer underwent curative surgery. R0 resection was performed in 585 patients (78.4%), R1 in 61 (8.2%) and R2 in 100 (13.4%). Univariate and multivariate analysis included 28 preoperative, clinical, tumor and therapeutic parameters.RESULTS: Multivariate analysis showed that factors predictive of complete resection R0 were: absence of any modification of the esophageal axis on the barium swallow (P=0.054), a partial or complete response to preoperative radio-chemotherapy (P=0.042), tumor height<10 cm (P=0.1) and tumor diameter<30 mm (P=0.01). Three groups of patients were identified from the 2 most significant variables. Group 1: no deviation of the axis on the barium swallow (n=501). Group 2: deviation of the axis on the barium swallow and partial or complete response to radiochemotherapy (n=91). Group 3: deviation of the axis on the barium swallow and no response to radiochemotherapy or no preoperative treatment (n=126). For the three groups, rate of R0 resection was 82.6%, 80.1% and 61.1% and 5-year actuarial survival 36%, 27% and 14%, respectively. These rates were significantly different between groups (P<10(- 4)) and two by two (P<0.04).CONCLUSION: Complete resection of esophageal cancer is predictable. After validation with an independent population the findings presented here could be used to establish stratification criteria for future therapeutic trials.  相似文献   
16.
Background: Chronic kidney disease (CKD) is a renal disorder characterized by the accumulation of uremic toxins with limited strategies to reduce their concentrations. A large amount of data supports the pivotal role of intestinal microbiota in CKD complications and as a major source of uremic toxins production. Here, we explored whether fecal microbiota transplantation (FMT) could be attenuated in metabolic complication and uremic toxin accumulation in mice with CKD. Methods: Kidney failure was chemically induced by a diet containing 0.25% (w/w) of adenine for four weeks. Mice were randomized into three groups: control, CKD and CKD + FMT groups. After four weeks, CKD mice underwent fecal microbiota transplantation (FMT) from healthy mice or phosphate buffered saline as control. The gut microbiota structure, uremic toxins plasmatic concentrations, and metabolic profiles were explored three weeks after transplantation. Results: Associated with the increase of alpha diversity, we observed a noticeable improvement of gut microbiota disturbance, after FMT treatment. FMT further decreased p-cresyl sulfate accumulation and improved glucose tolerance. There was no change in kidney function. Conclusions: These data indicate that FMT limited the accumulation of uremic toxins issued from intestinal cresol pathway by a beneficial effect on gut microbiota diversity. Further studies are needed to investigate the FMT efficiency, the timing and feces amount for the transplantation before, to become a therapeutic option in CKD patients.  相似文献   
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International Journal of Clinical Pharmacy - Background Ethical reasoning informs decision making and professional judgement, is guided by codes of ethics and conduct, and requires navigation...  相似文献   
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Tetraspanins are integral transmembrane proteins organized in microdomains displaying specific and direct interactions with other tetraspanins and molecular partners. Among them, CD81 has been implicated in a variety of physiological and pathological processes. CD81 also plays a crucial role in pathogen entry into host cells, including hepatitis C virus (HCV) entry into hepatocytes. HCV is a major cause of liver cirrhosis and hepatocellular carcinoma. HCV entry into hepatocytes is a complex process that requires the coordinated interaction of viral and host factors for the initiation of infection, including CD81, scavenger receptor BI, claudin-1, occludin, membrane-bound host cell kinases, Niemann-Pick C1 Like 1, Harvey rat sarcoma viral oncogene homolog (HRas), CD63 and transferrin receptor 1. Furthermore, recent data in HCV model systems have demonstrated that targeting critical components of tetraspanins and associated cell membrane proteins open new avenues to prevent and treat viral infection.  相似文献   
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