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101.
Study Type – Therapy (case series)
Level of Evidence 4 What’s known on the subject? and What does the study add? Laparoscopic radical nephrectomy (LRN) can be performed by a retroperitoneal approach with similar efficacy compared to the transperitoneal approach. However, the oncological acceptance of LRN has been based on studies which have been carried out primarily by transperitoneal approach, and oncological results of the retroperitoneal approach alone are lacking. Our study confirmed that retroperitoneal laparoscopic radical nephrectomy is oncologically‐equivalent to transperitoneal approach in homogeneous group with the final pathological diagnosis of clear cell RCC.

OBJECTIVE

  • ? To investigate the oncological efficacy of retroperitoneal laparoscopic radical nephrectomy (RLRN) compared with transperitoneal laparoscopic radical nephrectomy (TLRN) for the management of clear‐cell renal cell carcinoma (RCC).

PATIENTS AND METHODS

  • ? With emphasis on survival and disease recurrence, a retrospective analysis was made of 580 patients who underwent TLRN (472 patients) or RLRN (108 patients) at 23 institutions between January 1997 and December 2007.
  • ? Inclusion criteria were clear‐cell RCC, stage pT1 to pT2 without any nodal involvement, and metastasis.
  • ? Overall survival and recurrence‐free survival curves were estimated using the Kaplan–Meier method.
  • ? To assess the association between the surgical approach and survival outcomes, Cox proportional hazard models were constructed.

RESULTS

  • ? The median follow‐up was 30 months in the TLRN group and 35.6 months in the RLRN group. Both groups were comparable regarding age, gender, body mass index (BMI), Fuhrman’s grade, size of tumours and stage.
  • ? Kaplan–Meier curves and the log‐rank test showed no significant difference between the TLRN and RLRN groups in 5‐year overall (92.6% vs 94.5%; P = 0.669) and recurrence‐free survival (92.0% vs 96.2%; P = 0.244).
  • ? In a Cox regression model with age, gender, Eastern Cooperative Oncology Group performance status, BMI, nuclear grade and T‐stage adjusted variables, no significant difference was found between the two surgical approaches.

CONCLUSION

  • ? The present study is the largest oncological analysis for laparoscopic radical nephrectomy (LRN) comparing transperitoneal and retroperitoneal approaches. The data from it provide the objective evidence to suggest similar oncological outcomes for both approaches to LRN.
  相似文献   
102.
103.
Freeny  PC; Marks  WM 《Radiology》1986,160(3):613-618
Bolus dynamic and delayed computed tomographic (CT) scans of the liver were evaluated in 43 patients with 54 hepatic hemangiomas and 111 patients with primary or secondary malignant hepatic neoplasms. Twelve patterns of contrast enhancement were recognized during the bolus dynamic phase and delayed scanning. A "typical" CT pattern for hemangiomas (present in 29 of 54 hemangiomas [53.7%]) was established: (a) diminished attenuation prior to intravenous contrast medium administration (excluding lesions arising in a liver with diffuse fatty infiltration), (b) peripheral contrast enhancement during the bolus dynamic phase, and (c) complete isodense fill-in on delayed scan images. Using these criteria, we distinguished hemangiomas from malignant neoplasms in most patients. Only one of 63 (1.6%) malignant neoplasms manifested these typical CT criteria of hemangioma. There is an 86% chance that a lesion with the typical CT appearance of hemangioma is actually a hemangioma, even when found in a patient with a known nonhepatic primary neoplasm.  相似文献   
104.

Objective

The goal of this study was to evaluate consistencies and discrepancies between clinician-administered and self-report versions of the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and to examine relationships between these scales and personality traits.

Methods

A total of 106 patients with obsessive-compulsive disorder (OCD) participated in this study. All participants were assessed with both clinician-administered and self-report versions of the Y-BOCS. The Structured Clinical Interview for DSM-IV Axis II Disorders Personality Questionnaire (SCID-II-PQ) was used to evaluate relationships between personality traits and scores on the Y-BOCS.

Results

Scores on the clinician-administered Y-BOCS and its obsession subscale were significantly higher than were those on the self-report version. However, we found no significant differences in compulsion subscale scores. We also found that the discrepancies in the scores on the two versions of the Y-BOCS and its compulsion subscale were significantly positively correlated with scores for narcissistic personality traits on the SCID-II-PQ. Additionally, narcissistic personality traits had a significant effect on the discrepancy in the scores on the two versions of the Y-BOCS and its compulsion subscale in the multiple linear regression analysis.

Conclusion

This is the first study to elucidate relationships between personality traits and discrepancies between scores on the two versions of the Y-BOCS. Although clinicians tend to rate obsessive symptoms as being more severe than do patients, clinicians may underestimate the degree to which individuals with narcissistic personality traits suffer more from subjective discomfort due to compulsive symptoms. Therefore, the effect of personality traits on symptom severity should be considered in the treatment of OCD.  相似文献   
105.
The aim of this study was to assess imaging findings on CT or MR images of histologically proven ovarian cystadenofibromas. In the period 1995–2001, 32 histologically proven ovarian cystadenofibromas were identified in 28 women. Of the 32 ovarian cystadenofibromas, 16 tumors were purely cystic and the remaining 16 were complex cystic on CT or MR images. Solid components of 16 complex cystic tumors were seen as nodular (n=8) or trabecular (n=9) solid areas. One tumor had both nodular and trabecular solid components. Among 16 complex cystic tumors, 14 had thick or irregular septa; thus, half of ovarian cystadenofibromas had morphological imaging features of malignancy on CT or MR images. On histology, solid components in the cystic tumors were correlated with fibrous stromas that occasionally made a false-positive result for malignancy on imaging.  相似文献   
106.
There has recently been increasing interest in the development of radioprobes that specifically target proteins transcribed from expression of reporter genes of interest. The purpose of this study was to develop a radioprobe that targets one of the most widely used reporter genes, the bacterial lacZ gene. We synthesised and purified radioiodine-labelled phenylethyl--d-thiogalactopyranoside (PETG), a competitive inhibitor specific against Escherichia coli -galactosidase. We showed that [125I]iodo-PETG specifically binds to -galactosidase as verified by column chromatography and polyacrylamide gel electrophoresis after incubation of radiotracer with the protein. We also showed through enzyme kinetic studies that iodo-PETG retains inhibitory action against -galactosidase activity. COS-7 cells infected with a recombinant adenovirus expressing the lacZ gene had viral titre-dependent enhancements in [125I]iodo-PETG uptake (r2=0.897; P=0.001), which reached up to 642.5%±16.7% of control levels (P<0.00001). Moreover, the level of uptake was highly correlated to luminescent measurements of -galactosidase activity (r2=0.878; P<0.0001). These results confirm that radioiodine-labelled PETG specifically targets -galactosidase and that its uptake rates faithfully reflect levels of expression of the lacZ reporter gene. Further investigations were performed in nude mice bearing human neuroblastoma tumours transferred with the lacZ gene. Compared with control tumours, lacZ-expressing tumours were slightly better visualised on [123I]iodo-PETG images and had a modest increase in tumour to muscle count ratio (2.6±0.2 vs 1.9±0.1, P<0.05). The present results provide proof-of-principle for the potential of radiolabelled inhibitors as promising radiotracers to monitor lacZ gene expression levels. Future modifications to improve cell permeability should enhance in vivo contrast levels and may allow the use of radiolabelled -galactosidase inhibitors for non-invasive monitoring of lacZ gene expression.This work was presented in part at the 49th Annual Meeting of the Society of Nuclear Medicine, LA, USA, June 15–19, 2002.  相似文献   
107.
Discrimination of tuberculous spondylitis from pyogenic spondylitis on MRI   总被引:2,自引:0,他引:2  
OBJECTIVE: The purpose of this study was to determine the accuracy of MRI for discrimination between tuberculous spondylitis and pyogenic spondylitis. MATERIALS AND METHODS: MR images of 52 patients who had MRI of the spine and confirmed spondylitis were retrospectively reviewed. After review of medical records, we compared MRI findings in 20 patients with tuberculous spondylitis and 20 patients with pyogenic spondylitis. Statistical analysis was performed with the chi-square test. RESULTS: The reviewer identified tuberculous spondylitis with sensitivity, specificity, and accuracy of 100% (20/20), 80% (16/20), and 90% (36/40), and pyogenic spondylitis with sensitivity, specificity, and accuracy of 80% (16/20), 100% (20/20), and 90% (36/40), respectively. The patients with tuberculous spondylitis had a significantly higher incidence of MRI findings as follows (p < 0.05): a well-defined paraspinal abnormal signal (95% [19/20] in tuberculous vs 25% [5/20] in pyogenic), a thin and smooth abscess wall (95% [19/20] vs 15% [3/20]), combination of both findings (90% [18/20] vs 0% [0/20]), presence of paraspinal or intraosseous abscess (95% [19/20] vs 50% [10/20]), subligamentous spread to three or more vertebral levels (85% [17/20] vs 40% [8/20]), involvement of multiple vertebral bodies (60% [12/20] vs 25% [5/20]), thoracic spine involvement (40% [8/20] vs 10% [2/20]), and hyperintense signal on T2-weighted images (95% [19/20] vs 65% [13/20]). CONCLUSION: MRI was accurate for differentiation of tuberculous spondylitis from pyogenic spondylitis.  相似文献   
108.
109.
Pathologic extranodal extension (pENE) impacts treatment planning and is an important prognostic indicator for patients with head and neck squamous cell carcinoma (HNSCC). Computed tomography (CT) is a commonly used modality for assessment of radiographic ENE (rENE). To determine the predictive value of CT‐identified rENE in predicting pENE, we performed a systematic review through a search of 4 databases (PubMed, Scopus, Cochrane, and OVID). Meta‐analysis of diagnostic performance based on human papillomavirus (HPV) status was conducted. For HPV‐negative HNSCC, pooled sensitivity, specificity, and accuracy were 60.6%, 93.3%, and 82.6%, respectively. Overall positive predictive value (PPV) was 82.7%. For HPV‐positive HNSCC, pooled sensitivity, specificity, and accuracy were 77.7%, 72.2%, and 63.8%, respectively. Overall PPV was 68.6%. Significant differences were observed in diagnostic performance parameters between the two cohorts. The radiographic characteristics of HPV‐positive and HPV‐negative nodal metastases in HNSCC differ and radiographic evaluation of ENE in HPV‐positive nodes is challenging. Development of refined imaging characteristics of HPV‐positive nodes is needed to improve diagnostic performance.  相似文献   
110.
BackgroundThere is an increasing demand for prognostic immune biomarkers of cancer. The prognostic significance of immune markers has been shown for various cancers, but biomarkers of bladder cancer (BCa) have not been fully evaluated. To clarify the role of human leukocyte antigen DR alpha chain (HLA-DRA) in BCa development, we examined expression of HLA-DRA mRNA in tissue samples of non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC).Materials and MethodsTissues of 96 NMIBC, 43 MIBC and 59 controls comprising noncancerous BCa surrounding tissues were used to examine the expression of HLA-DRA gene by real-time polymerase chain reaction. The expression of up-stream genes regulating HLA-DRA were also measured to explain the role of HLA-DRA in BCa.ResultsPatients with high grade NMIBC showed higher expression of HLA-DRA than those with low grade NMIBC (P < 0.05). In addition, NMIBC patients who progressed to MIBC showed high expression of HLA-DRA mRNA. Kaplan-Meier analysis showed that NMIBC patients with low expression of HLA-DRA had better progression-free survival than those with high expression (P = 0.004). Moreover, the expression of genes regulating HLA-DRA varied in NMIBC and MIBC, indicating a different immunoregulation effect of HLA-DRA in both cancers.ConclusionsHigh expression of HLA-DRA in NMIBC patients has implications for patient stratification strategies, as well as for BCa tumor immunology.  相似文献   
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