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991.
A 43-year-old man presented with long-standing left flank pain. A plain abdominal radiograph and intravenous urography (IVU) revealed a giant ureteral stone measuring 6.2 × 2.2 cm causing ureteral obstruction. A non-enhanced computerized tomography (CT) scan showed a significantly atrophied right kidney and left hydronephroureterosis with a giant stone. A left transperitoneal laparoscopic ureterolithotomy was performed with excellent results.  相似文献   
992.
Anxiety is linked to compromised interactions between the amygdala and the dorsal and ventral medial prefrontal cortex (mPFC). While numerous task-based neuroimaging studies show that anxiety levels predict amygdala-mPFC connectivity and response magnitude, here we tested the hypothesis that anxiety would predict functional connectivity between these brain regions even during rest. Resting-state functional magnetic resonance imaging scans and self-reported measures of anxiety were acquired from healthy subjects. At rest, individuals with high anxiety were characterized by negatively correlated amygdala-ventral mPFC functional connectivity, while low anxious subjects showed positively correlated activity. Further, high anxious subjects showed amygdala-dorsal mPFC activity that was uncorrelated, while low anxious subjects showed negatively correlated activity. These data show that amygdala-mPFC connectivity at rest indexes normal individual differences in anxiety.  相似文献   
993.
The aim of this study was to analyze the clinical characteristics of thoracic ossified ligamentum flavum (OLF) and to elucidate prognostic factors as well as effective surgical treatment modality. The authors analyzed 106 thoracic OLF cases retrospectively from January 1999 to December 2008. The operative (n = 40) and the non-operative group (n = 66) were diagnosed by magnetic resonance imaging (MRI) and/or computed tomography (CT) imaging. We excluded cases exhibiting ventral compressive lesions causing subarachnoid space effacement in thoracic vertebrae as well as those with a coexisting cervical compressive myelopathy. Those in the operative group were treated with decompressive laminectomy as well as resection of OLF. The preoperative neurologic status and postoperative outcomes of patients, as indicated by their modified Japanese Orthopedic Association (mJOA) scores and recovery rate (RR), Modic changes, the axial (fused or non-fused) and sagittal (omega or beak) configurations of OLF, and the ratios of the cross-sectional area (CSA) and anteroposterior diameter (APD) of the most compressed level were studied. The most commonly affected segment was the T10–11 vertebral body level (n = 49, 27.1%) and the least affected segment was the T7–8 level (n = 1, 0.6%). The ratios of the CSA in non-fused and fused types were 77.3 and 59.3% (p < 0.001). When Modic changes were present with OLF, initial mJOA score was found to be significantly lower than those without Modic change (7.62 vs. 9.09, p = 0.033). Neurological status improved after decompressive laminectomy without fusion (preoperative vs. last mJOA; 7.1 ± 2.01 vs. 8.57 ± 1.91, p < 0.001). However, one patient exhibited transient deterioration of her neurological status after surgery. In the axial configuration, fused-type OLF revealed a significant risk for a decreased postoperative mJOA score (0–7, severe and moderate) (Odds ratio: 5.54, χ2 = 4.41, p = 0.036, 95% CI: 1.014–30.256). The results indicated that the new categorization of axial-type of OLF is a helpful predictor of postoperative patient outcome and fused type was related with poor prognosis. In OLF cases free from ventral lesions compressing the spinal cord, decompressive laminectomy is enough for successful surgical outcome. Therefore, early surgical treatment will be considered in cases with fused-type OLF compressing spinal cord even though they do not have myelopathic symptoms.  相似文献   
994.

Background

To evaluate the clinical efficacy of three-level anterior cervical arthrodesis with polyethyletherketone (PEEK) cages and plate fixation for aged and osteoporotic patients with degenerative cervical spinal disorders.

Methods

Twenty one patients, who had undergone three-level anterior cervical arthrodesis with a cage and plate construct for degenerative cervical spinal disorder from November 2001 to April 2007 and were followed up for at least two years, were enrolled in this study. The mean age was 71.7 years and the mean T-score using the bone mineral density was -2.8 SD. The fusion rate, change in cervical lordosis, adjacent segment degeneration were analyzed by plain radiographs and computed tomography, and the complications were assessed by the medical records. The clinical outcomes were analyzed using the SF-36 physical composite score (PCS) and neck disability index (NDI).

Results

Radiological fusion was observed at a mean of 12.3 weeks (range, 10 to 15 weeks) after surgery. The average angle of cervical lordosis was 5° preoperatively, 17.6° postoperatively and 16.5° at the last follow-up. Degenerative changes in the adjacent segments occurred in 3 patients (14.3%), but revision surgery was unnecessary. In terms of instrument-related complications, there was cage subsidence in 5 patients (23.8%) with an average of 2.8 mm, and loosening of the plate and screw occurred in 3 patients (14.3%) but there were no clinical problems. The SF-36 PCS before surgery, second postoperative week and at the last follow-up was 29.5, 43.1, and 66.2, respectively. The respective NDI was 55.3, 24.6, and 15.9.

Conclusions

For aged and osteoporotic patients with degenerative cervical spinal disorders, three-level anterior cervical arthrodesis with PEEK cages and plate fixation reduced the pseudarthrosis and adjacent segment degeneration and improved the clinical outcomes. This method is considered to be a relatively safe and effective treatment modality.  相似文献   
995.

Background

This study was undertaken to investigate the trends of orthopedic publications during the last decade, and to document the country of origin, journal, funding source, and language of contribution using PubMed.

Methods

Orthopedic articles published between 2000 and 2009 were retrieved from PubMed using the following search terms: "orthopaedic[Affiliation] AND ("2000/1/1"[PDAT]: "2009/12/31"[PDAT])" and "orthopedic[Affiliation] AND ("2000/1/1"[PDAT]: "2009/12/31"[PDAT])." The articles were downloaded in XML file format, which contained the following information: article title, author names, journal names, publication dates, article types, languages, authors'' affiliations and funding sources. These information was extracted, sorted, and rearranged using the database''s management software. We investigated the annual number of published orthopedic articles worldwide and the annual rate of increase. Furthermore, the country of publication origin, journal, funding source, and language of contribution were also investigated.

Results

A total of 46,322 orthopedic articles were published and registered in PubMed in the last 10 years. The worldwide number of published orthopedic articles increased from 2,889 in 2000 to 6,909 in 2009, showing an annual increase of 384.6 articles, or an annualized compound rate of 10.2%. The United States ranked highest in the number of published orthopedic articles, followed by Japan, the United Kingdom, Germany, and the Republic of Korea. Among the orthopedic articles published worldwide during the last 10 years, 37.9% pertained studies performed in the United States. Fifty-seven point three percent (57.3%) of articles were published in journals established in the United States. Among the published orthopaedic articles, 4,747 articles (10.2%) disclosed financial support by research funds, of which 4,688 (98.8%) articles utilized research funds from the United States. Most articles were published in English (97.2%, 45,030 articles).

Conclusions

The number of published orthopedic articles has been increasing over the last decade. The number of orthopedic articles, journals publication, and funding sources were dominated by research conducted in the United States, while share and growth of Asian countries including Japan, the Republic of Korea, and China were notable.  相似文献   
996.
997.
Jeong IG  Ro JY  Kim SC  You D  Song C  Hong JH  Ahn H  Kim CS 《BJU international》2011,108(1):38-43
Study Type – Therapy (case series)
Level of Evidence 4 What’s known on the subject? and What does the study add? Although extranodal extension in node‐positive patients may provide prognostic information in certain urological malignancies, contradictory results have been reported in node‐positive patients after radical cystectomy for bladder cancer. We examined whether extranodal extension could have an impact on the outcomes of node‐positive patients who underwent radical cystectomy for bladder cancer in a single large tertiary hospital. We have shown that the presence of extranodal extension was not an independent prognostic factor in node‐positive patients after radical cystectomy and pelvic lymphadenectomy for bladder cancer.

OBJECTIVE

? To examine whether extranodal extension (ENE) has an impact on the outcome of node‐positive patients who underwent radical cystectomy for bladder cancer.

PATIENTS AND METHODS

? Of 543 consecutive patients who underwent radical cystectomy for urothelial carcinoma of the bladder between 1990 and 2007, 112 patients with lymph node metastasis detected on histological examination were evaluated with regard to recurrence‐free survival (RFS) and disease‐specific survival (DSS) based on ENE status.

RESULTS

? The overall 5‐year RFS and DSS rates were 22.3% and 33.8%, respectively. ENE was observed in 41 (36.6%) of the 112 patients. ? The presence of ENE was associated with advanced pathological nodal status (P= 0.004), more positive lymph nodes (P= 0.006), and higher lymph node density (P < 0.001). ? The incidence of positive ENE increased with large positive lymph node diameter (P < 0.001). ? Multivariate analysis showed that lymph node density (hazard ratio (HR) = 2.39, 95% CI 1.09–5.24, P= 0.029; and HR = 3.13, 1.43–6.84, P= 0.004) and use of adjuvant chemotherapy (HR = 1.80, 1.02–3.20, P= 0.041; and HR = 2.07, 1.13–3.79, P= 0.018) were significant predictors of RFS and DSS, respectively. ? After adjustment for other prognostic factors, ENE was not significantly related to RFS (P= 0.825) and DSS (P= 0.961) by multivariate analysis.

CONCLUSIONS

? The presence of ENE was not an independent prognostic factor in node‐positive patients after radical cystectomy for bladder cancer. ? Additional prospective studies are needed to determine the independent prognostic role of ENE.  相似文献   
998.
Lee KS  Han BH  Chun YK  Kim HS  Kim EE 《Clinical imaging》1999,23(6):1183-346
This retrospective study correlated the mammographic manifestations and averaged nuclear grades using Holland, Van-Nuys, and Lagios classifications in 37 cases of ductal carcinoma in situ (DCIS); microcalcifications alone were seen in 59.4%, microcalcifications with associated mass in 19%, and mass alone in 21.6%. DCIS is more likely to be accompanied by microcalcifications than mass on mammography. Correlation is good between the nuclear grades of DCIS and mammographic manifestations.  相似文献   
999.
MRI of primary meningeal tumours in children   总被引:5,自引:0,他引:5  
Childhood meningeal tumours are uncommon and mostly meningiomas. We reviewed the histological and radiological findings in meningeal tumours in six children aged 12 years or less (four benign meningiomas, one malignant meningioma and one haemangiopericytoma). Compared to the adult counterpart, childhood meningiomas showed atypical features: cysts, haemorrhage, aggressiveness and unusual location. MRI features varied according to the site of the tumour, histology, haemorrhage, and presence of intra- or peritumoral cysts. Diagnosis of the extra-axial tumour was relatively easy in two patients with meningiomas, one malignant meningioma and one haemangiopericytoma. MRI findings strongly suggested an intra-axial tumour in two patients with benign meningiomas, because of severe adjacent edema. Awareness of the variable findings of childhood meningiomas and similar tumours may help in differentiation from brain tumours. Received: 22 September 1998 Accepted: 18 November 1998  相似文献   
1000.
The radiographic findings of Pneumocystis carinii pneumonia (PCP) are various. The typical findings are diffuse, bilateral, symmetric, finely granular, or reticular infiltrates. In patients taking aerosol pentamidine, atypical findings may be the first manifestation. One interesting radiologic finding of PCP is that the pneumonia may spare the irradiated lung. We report PCP developed in a patient undergoing irradiation for lung cancer. High-resolution CT revealed diffuse, bilateral, and symmetric ground-glass opacities with septal thickening in both lungs; however, the radiation port was spared and appeared as the “photographic negative of post-radiation pneumonia.” The distribution of the pneumonic infiltrates was altered by radiotherapy. Received: 27 July 1998; Revision received: 23 November 1998; Accepted: 4 January 1999  相似文献   
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