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71.
We analyzed a local database including 468 consecutive patients who underwent elective aortic abdominal surgery over an 8-yr period in a single institution. A new cardioprotective perioperative protocol was introduced in January 1997, and we questioned whether perioperative cardiac outcome could be favorably influenced by the application of a stepwise cardiovascular evaluation based on the American College of Cardiology/American Heart Association guidelines and by the use of antiadrenergic drugs. Clonidine was administered during surgery, and beta-blockers were titrated after surgery to achieve heart rates less than 80 bpm. We compared data of two consecutive 4-yr periods (1993-1996 [control period] versus 1997-2000 [intervention period]). Implementation of American College of Cardiology/American Heart Association guidelines was associated with increased preoperative myocardial scanning (44.3% vs 20.6%; P < 0.05) and coronary revascularization (7.7% vs 0.8%; P < 0.05). During the intervention period, there was a significant decrease in the incidence of cardiac complications (from 11.3% to 4.5%) and an increase in event-free survival at 1 yr after surgery (from 91.3% to 98.2%). Multivariate regression analysis showed that the combined administration of clonidine and beta-blockers was associated with a decreased risk of cardiovascular events (odds ratio, 0.3; 95% confidence interval, 0.1-0.8), whereas major bleeding, renal insufficiency, and chronic obstructive pulmonary disease were predictive of cardiac complications. In conclusion, cardiac testing was helpful to identify a small subset of high-risk patients who might benefit from coronary revascularization. Sequential and selective antiadrenergic treatments were associated with improved postoperative cardiac outcome. IMPLICATIONS: Implementation of American College of Cardiology/American Heart Association guidelines and use of antiadrenergic drugs were associated with better cardiac outcomes after major vascular surgery.  相似文献   
72.

Background  

Strategies for revising a ceramic-on-ceramic total hip prosthesis are controversial. Some consider reimplantation of a ceramic head on a well-fixed femoral stem inadvisable as it may lead to a fracture of the newly implanted head.  相似文献   
73.

Introduction and hypothesis

The aim was to assess the efficacy of three-compartment pelvic organ prolapse (POP) vaginal repair using the InteXen® biocompatible porcine dermal graft as compared to traditional colporrhaphy with sacrospinous ligament suspension.

Methods

Preoperative, operative, postoperative and follow-up data were collected retrospectively. Objective recurrence was defined as POP quantification ≥ stage II and subjective recurrence as a symptomatic bulge.

Results

Each group consisted of 63 patients. Surgery time was longer using InteXen® (72?±?24.5 vs 55?±?23.5 min, p?=?0.0002). Length of hospital stay (4.6?±?1.6 vs 4.9?±?2.1 days, p?=?0.34) as well as duration of follow-up (37.1 vs 35.7 months, p?=?0.45) were equivalent between the two groups. No case of mesh erosion or infection was noted. The objective (17% vs 8%, p?=?0.12) and subjective recurrence rates (13% vs 5%, p?=?0.12) between the two groups were not statistically different.

Conclusions

InteXen® was well tolerated but had similar efficacy to traditional colporrhaphy and sacrospinous ligament suspension.  相似文献   
74.
Delayed graft function (DGF) after kidney transplantation is associated with an increased risk of graft failure. We studied the histologic findings among adult kidney transplant recipients transplanted between January 2000 and June 2015 who had DGF and had a kidney biopsy within 14 days of transplant. Death censored graft failure (DCGF) and death at 1 and 3 years after transplant were examined. A total of 269 transplant recipients fulfilled our selection criteria, of which 152 (56.51%) had acute tubular necrosis (ATN), 44 (16.4%) had acute rejection (AR), mainly T-cell mediated rejection (n = 31), 35 (13%) had ATN with AR (mainly T-cell mediated rejection, n = 26), and 38 (14.1%) had other pathology. Compared with those with ATN alone, kidney transplant recipients with AR alone had a significantly higher risk of DCGF at 1 year post transplant (adjusted hazard ratio = 3.70; 95% confidence interval 1.5-9.5; P = .006). Those with AR alone had an increased risk of DCGF at 3 years post transplant (hazard ratio = 3.10; 95% confidence interval 1.3-8.5; P = .01) in crude analyses. There was no association between DGF etiology and mortality. Early renal biopsy can be used to distinguish AR, which has protocolized treatments, from other etiologies. This could potentially alter allograft survival within 1 year of transplant complicated by DGF.  相似文献   
75.
The European Society of Thoracic Surgeons (ESTS) organized a workshop dealing with lymph node staging in non-small cell lung cancer. The objective of this workshop was to develop guidelines for definitions and the surgical procedures of intraoperative lymph node staging, and the pathologic evaluation of resected lymph nodes in patients with non-small cell lung cancer (NSCLC). Relevant peer-reviewed publications on the subjects, the experience of the participants, and the opinion of the ESTS members contributing on line, were used to reach a consensus. Systematic nodal dissection is recommended in all cases to ensure complete resection. Lobe-specific systematic nodal dissection is acceptable for peripheral squamous T1 tumors, if hilar and interlobar nodes are negative on frozen section studies; it implies removal of, at least, three hilar and interlobar nodes and three mediastinal nodes from three stations in which the subcarinal is always included. Selected lymph node biopsies and sampling are justified to prove nodal involvement when resection is not possible. Pathologic evaluation includes all lymph nodes resected separately and those remaining in the lung specimen. Sections are done at the site of gross abnormalities. If macroscopic inspection does not detect any abnormal site, 2-mm slices of the nodes in the longitudinal plane are recommended. Routine search for micrometastases or isolated tumor cells in hematoxylin-eosin negative nodes would be desirable. Randomized controlled trials to evaluate adjuvant therapies for patients with these conditions are recommended. The adherence to these guidelines will standardize the intraoperative lymph node staging and pathologic evaluation, and improve pathologic staging, which will help decide on the best adjuvant therapy.  相似文献   
76.

Context

The clinical benefit of photodynamic diagnosis (PDD) with 5-aminolevulinic acid or hexaminolevulinate in addition to white-light cystoscopy (WLC) in bladder cancer has been discussed controversially.

Objective

To assess in a systematic review the effect of PDD in addition to WLC on (1) the diagnosis and (2) the therapeutic outcome of primary or recurrent non–muscle-invasive bladder cancer investigated by cystoscopy or transurethral resection.

Evidence acquisition

An electronic database search of Medline, Embase, the Cochrane Library, and CancerLit was undertaken, plus hand searching of relevant congress abstracts and urologic journals. Trials were included if they prospectively compared WLC with PDD in bladder cancer. The review process followed the guidelines of the Cochrane Collaboration. Two reviewers evaluated independently both trial eligibility and methodological quality and data extraction.

Evidence synthesis

The primary end point of diagnostic accuracy was additional detection rate. The primary end points of therapeutic outcome were residual tumour at second resection and recurrence-free survival (RFS). Seventeen trials were identified. Twelve diagnostic trials used WLC and PDD with the same patients. Seven reported results for the subgroup of patients with carcinoma in situ (CIS). Five randomised trials studied therapeutic outcome. The results were combined in random effects meta-analyses if end points, designs, and populations were comparable. Twenty percent (95% confidence interval [CI], 8–35) more tumour-positive patients were detected with PDD in all patients with non–muscle-invasive tumours and 39% (CI, 23–57) more when only CIS was analysed. Heterogeneity was present among diagnostic studies even when the subgroup of patients with CIS was investigated. Residual tumour was significantly less often found after PDD (odds ratio: 0.28; 95% CI, 0.15–0.52; p < 0.0001). RFS was higher at 12 and 24 mo in the PDD groups than in the WLC-only groups. The combined p value of log-rank tests of RFS was statistically significant (0.00002).

Conclusions

PDD detects more bladder tumour–positive patients, especially more with CIS, than WLC. More patients have a complete resection and a longer RFS when diagnosed with PDD.  相似文献   
77.
78.
Pothuaud L  Carceller P  Hans D 《BONE》2008,42(4):775-787
X-ray imaging remains a very cost-effective technique, with many applications in both medical and material science. However, the physical process of X-ray imaging transforms (e.g. projects) the 3-dimensional (3D) microarchitecture of the object or tissue being studied into a complex 2D grey-level texture. The 3D/2D projection process continues to be a difficult mathematical problem, and neither demonstrations nor well-established correlations have positioned 2D texture analysis-based measurement as a valid indirect evaluation of 3D microarchitecture. The trabecular bone score (TBS) is a new grey-level texture measurement which utilizes experimental variograms of 2D projection images. The aim of the present study was to determine the level of correlation between the 3D characteristics of trabecular bone microarchitecture, as evaluated using muCT reconstruction, and TBS, as evaluated using 2D projection images derived directly from 3D muCT reconstruction. Analyses were performed using sets of human cadaver bone samples from different anatomical sites (lumbar spine, femoral neck, and distal radius). Significant correlations were established via standard multiple regression analysis, and via the use of a generic mathematical 3D/2D relationship. In both instances, the correlations established a significant relationship between TBS and two 3D characteristics of bone microarchitecture: bone volume fraction and mean bone thickness. In particular, it appears that TBS permits to accurately differentiate between two 3D microarchitectures that exhibit the same amount of bone, but different trabecular characteristics. These results demonstrate the existence of a robust and generic relationship, taking into consideration a simplified model of a 2D projection image. Ultimately, this may lead to using TBS measurements directly on DXA images obtained in routine clinical practice.  相似文献   
79.
OBJECTIVE: One of the complications of CPB is the systemic inflammatory response syndrome (SIRS). Recent developments tend to minimize the biological impact of CPB in using miniaturized closed circuit with reduced priming volume and less blood-air interface. The benefit of these miniaturized closed circuits in terms of inflammatory response has been proved in coronary surgery. However, in open heart surgery, the CPB circuit is no more closed and the benefit of the miniaturized set-up could disappear. The aim of the study is to compare the SIRS between standard and miniaturized circuits in aortic surgery. METHODS: Forty patients who underwent singular aortic valve replacement were randomly assigned either to a standard CPB (group A, n=20) or to a miniaturized CPB (group B, n=20). Pertinent clinical and surgical data were collected. Hematological parameters (leukocyte and neutrophil counts) and biochemical parameters (C-reactive protein, cytokine tests) were determined pre-, on and post-CPB. RESULTS: There were an increase in leukocyte and neutrophil counts and a decline in hematocrit in both groups. In both groups, there was a raise after CPB, in C-reactive protein, IL-6, TNF-alpha, neutrophil elastase, and IL-10. However, the raises of elastase and TNF-alpha were significantly lower after the weaning of miniaturized CPB (116+/-46 ng/ml and 10+/-4 pg/ml, respectively) compared to standard CPB (265+/-120 ng/ml, P=0.01 and 18+/-7 pg/ml, P=0.03). The raise of IL-10 is also lower with miniaturized circuit (15+/-6 pg/ml) compared to standard circuit (51+/-26, P=0.004). CONCLUSIONS: This study demonstrates in aortic surgery, the lesser inflammatory response of a miniaturized CPB compared to a standard CPB. However, there is always some inflammation after CPB and a small bio-reactive free perfusion circuit is still to be found in open heart surgery.  相似文献   
80.
PURPOSE: To evaluate the safety and efficacy of gadoxetic acid disodium-enhanced magnetic resonance (MR) imaging for the detection of focal liver lesions, with results of histopathologic examination and/or intraoperative ultrasonography used as a standard of reference. MATERIALS AND METHODS: One hundred sixty-nine patients who were known to have or suspected of having focal liver lesions and were scheduled for liver surgery were included in this study. Results in 131 patients could be included in the efficacy analysis. MR imaging was performed before and immediately and 20 minutes after bolus injection of 0.025 mmol/kg of the liver-specific hepatobiliary contrast agent gadoxetic acid. T1-weighted gradient-echo (with and without fat saturation and including dynamic data sets) and T2-weighted fast spin-echo/turbo spin-echo sequences were performed. All images were evaluated on site and by three independent and blinded off-site reviewers. Lesion matching based on the standard-of-reference results was performed. Differences in lesion detection with precontrast and with postcontrast MR images were assessed with the two-sided Wilcoxon signed rank test. RESULTS: Gadoxetic acid was well tolerated. In the on-site review, the number of patients in whom all lesions were correctly matched increased from 89 of 129 patients at precontrast MR imaging to 103 of 129 patients at postcontrast MR imaging. In the off-site evaluation, the number of patients in whom all lesions were correctly matched and the corresponding sensitivity values increased from 72 (55.8%), 68 (52.7%), and 66 (51.2%) with the precontrast images to 88 (68.2%), 69 (53.5%), and 76 (58.9%) with the postcontrast images for readers 1, 2, and 3, respectively. Two of the three blinded readers showed a statistically significant difference in lesion detection between precontrast and postcontrast MR imaging (P <.001 and P =.008). A large number of additionally correctly detected and localized lesions were smaller than 1 cm. CONCLUSION: MR imaging with gadoxetic acid is safe and improves lesion detection and localization.  相似文献   
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