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41.
A novel application of the implantable Port-a-Cath (PAC) system is described in the context of cellular transplantation. A silicone catheter was inserted in a collateral branch of the portal vein and connected to a port device positioned subcutaneously on the left thoracic cage. This permanent vascular access allowed iterative intraportal infusions of allogenic hepatocytes without the need of repeated transhepatic catheterization of the portal vein. Using this technique, repeated infusions of cryopreserved and / or fresh hepatocytes were successfully carried out in 3 children with inborn errors of liver metabolism, with the aim of progressively providing a sufficient mass of transplanted liver cells to stabilize the metabolic condition of the patients. We suggest that this technique might also be valuable in pancreatic islet cell transplantation.  相似文献   
42.
Renal transplantation from living kidney donors is still relatively marginal in most of the European countries. However, this source of kidney grafts may help to overcome in part the organ donor shortage of cadaveric donors. The living donor strategy implies correct and objective information about donation risks and completely free acceptance of the living candidate of the donation. In this paper, we reviewed the consequences of kidney donation on the living donor health, considering very short term (linked to the surgery), short term (effect of nephrectomy on glomerular filtration rate) and long term (risk of mortality, chronic kidney disease, proteinuria and hypertension) consequences of kidney donation.  相似文献   
43.

Purpose

Primary paraclinical investigation to look for femoral morphological abnormality consistent with cam-type anterior femoroacetabular impingement (FAI) must include specific radiographic projections of the hip from the following: cross-table, frog-leg or Dunn (90° and 45° flexion). We use a frog-leg type view with fixed angles as described by Chiron, obtained with the patient in a supine position, with the hip in 45° flexion-abduction and 30° external rotation. The X-ray beam is anteroposterior and centred on the femoral head. We evaluated this view by comparing it with other views in common use.

Methods

In this experimental study, we created artificial radio-opaque morphological abnormalities secured onto normal femoral necks. The femurs were placed in relation to a fixed pelvis using orthogonal landmarks, in the positions of the various radiographic views. The digital radiographs were analysed by two observers. Nineteen femurs were included to reveal a difference of 5° between the alpha angle of Nötzli et al. [11] measured on the Dunn view and the frog-leg 45/45/30 view (Student’s paired test).

Results

The highest mean values of the alpha angle of Nötzli were always obtained with the frog-leg 45/45/30 view (87.4°, 86.2°, 84.5°) and the lowest with the cross-table view. We found a mean difference of 8.95° with the 90° Dunn view (P = 0.00007), 3.44° with the 45° Dunn view (P = 0.004) and 13.47° with the cross-table view (P = 0.002).

Conclusions

This experimental study confirmed the value of the frog-leg 45/45/30 view in assisting diagnosis of cam-type FAI.  相似文献   
44.
Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) have emerged worldwide. These CA-MRSA are different from classical hospital-acquired MRSA. They share common characteristics: they affect mainly young subjects, without past medical history. The majority of strains produce the Panton-Valentine leukocidin. They are mainly responsible for suppurative skin infections and rarely for invasive infections such as necrotizing pneumonia. The situation in the US is alarming with a main circulating clone the USA300 clone, whereas in Europe, the diffusion of CA-MRSA strains remains limited. It is important to take advantage of the experience acquired from the US to limit the potential spread of such CA-MRSA strains.  相似文献   
45.

Background

Technetium Tc 99m bone scintigraphy (BS) and contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) of the pelvis and abdomen are universally recommended for detecting prostate cancer (PCa) metastases in cancer of all stages. However, this two-step approach has limited sensitivity and specificity.

Objective

Evaluate the diagnostic accuracy of whole-body MRI (WBMRI) as a one-step screening test for PCa metastases.

Design, setting, and participants

One hundred consecutive PCa patients at high risk for metastases prospectively underwent WBMRI, CT, and BS completed with targeted x-rays (BS/TXR) in case of equivocal BS. Four independent reviewers reviewed the images.

Measurements

This study compares the diagnostic performance of WBMRI, CT, BS, and BS/TXR in detecting PCa metastases using area under the curve (AUC) receiver operator characteristics. A best valuable comparator (BVC) approach was used to adjudicate final metastatic status in the absence of pathologic evaluation.

Results and limitations

Based on the BVC, 68 patients had metastases. The sensitivity of BS/TXR and WBMRI for detecting bone metastases was 86% and 98–100%, respectively (p < 0.04), and specificity was 98% and 98–100%, respectively. The first and second WBMRI readers respectively identified bone metastases in 7 and 8 of 55 patients with negative BS/TXR. The sensitivity of CT and WBMRI for detecting enlarged lymph nodes was similar, at 77–82% for both; specificity was 95–96% and 96–98%, respectively. The sensitivity of the combination of BS/TXR plus CT and WBMRI for detecting bone metastases and/or enlarged lymph nodes was 84% and 91–94%, respectively (p = 0.03–0.10); specificities were 94–97% and 91–96%, respectively. The 95% confidence interval of the difference between the AUC of the worst WBMRI reading and the AUC of any of the BS/TXR plus CT lay within the noninferiority margin of ±10% AUC.

Conclusions

WBMRI outperforms BS/TXR in detecting bone metastases and performs as well as CT for enlarged lymph node evaluation. WBMRI can replace the current multimodality metastatic work-up for the concurrent evaluation of bones and lymph nodes in high-risk PCa patients.  相似文献   
46.

Introduction and hypothesis

Hydrodissection incorporating different types of vasoconstrictors is commonly used in vaginal prolapse surgery. There is little evidence as to whether it adds clinical value or whether it exposes the patient to unnecessary risk. The aim of this study was to compare the effect of a vasoconstrictor compared with saline alone on operative blood loss and cardiovascular parameters in a randomised clinical trial setting.

Methods

Patients undergoing vaginal prolapse surgery were randomised to an ornipressin (Por-8, Ferring) solution or saline alone for hydrodissection. The surgeon and patient were blinded to the solution used. Operative blood loss was accurately quantified and blood pressure and pulse readings recorded Pre, intra- and postoperatively.

Results

Eighty women were randomised. There was a statistically significant difference in the median blood loss: 35 ml (1-209 ml) in the ornipressin group compared with 81 ml (2-328 ml) in the saline group, p?=?0.03. There was no statistically significant difference in the median pre and postoperative blood pressure or pulse rate between groups.

Conclusions

The use of a vasoconstrictor (ornipressin) resulted in a statistically significant decrease in operative blood loss during vaginal prolapse surgery. This occurred without any significant changes in measured cardiovascular parameters.
  相似文献   
47.
Long‐term outcomes in renal transplant recipients withdrawn from steroid and submitted to further minimization of immunosuppressive regimen after 1 year are lacking. In this multicenter study, 204 low immunological risk kidney transplant recipients were randomized 14.2 ± 3.7 months post‐transplantation to receive either cyclosporine A (CsA) + azathioprine (AZA; n = 53), CsA + mycophenolate mofetil (MMF; n = 53), or CsA monotherapy (n = 98). At 3 years postrandomization, the occurrence of biopsy for graft dysfunction was similar in bitherapy and monotherapy groups (21/106 vs. 26/98; P = 0.25). At 10 years postrandomization, patients’ survival was 100%, 94.2%, and 95.8% (P = 0.25), and death‐censored graft survival was 94.9%, 94.7%, and 95.2% (P = 0.34) in AZA, MMF, and CsA groups, respectively. Mean estimated glomerular filtration rate was 70.4 ± 31.1, 60.1 ± 22.2, and 60.1 ± 19.0 ml/min/1.73 m2, respectively (P = 0.16). The incidence of biopsy‐proven acute rejection was 1.4%/year in the whole cohort. None of the patients developed polyomavirus‐associated nephropathy. The main cause of graft loss (n = 12) was chronic antibody‐mediated rejection (n = 6). De novo donor‐specific antibodies were detected in 13% of AZA‐, 21% of MMF‐, and 14% of CsA‐treated patients (P = 0.29). CsA monotherapy after 1 year is safe and associated with prolonged graft survival in well‐selected renal transplant recipient ( ClinicalTrials.gov number: 980654).  相似文献   
48.
Background  Gastrointestinal stromal tumors (GISTs) are the main mesenchymal neoplasms in the gastrointestinal tract. Tumor size, mitotic rate, and location correlate with potential malignancy and recurrence rate. Results of surgical treatment of gastric GIST are analyzed with emphasis on recurrence of disease after intermediate follow-up. Methods  From 1998 to 2006, a total of 63 patients (median age 62.1 ± 14.1) underwent gastric resection for GIST. Fifty-five patients (93.6%) returned for follow-up investigations, which included computed tomography in 45, gastroscopy in 32, and endosonography in 29. Positron emission tomography was done in five patients. Results  Mean tumor size was 5.3 ± 3.8 cm. Open atypical gastric resection was done in 32, distal gastric resection in five, and remnant gastrectomy in four patients. Laparoscopic gastric resection was initiated in 22 patients; the conversion rate was four of 22 (18.2%). Overall, R0 resection was reached in 61/63 patients (96.8%). According to the Fletcher criteria, 33 tumors (52.4%) were classified as intermediate or high risk GIST. Six patients (9.5%) died of unrelated causes before follow-up. After a median follow-up of 2.5 years, overall recurrence rate was 7.0% after R0 resection. Conclusion  Histologically proven complete resection is an effective treatment for gastric GIST. Laparoscopic procedures were carried out successfully in selected patients. Preliminary data were presented at the annual meeting of the European Association of Endoscopic Surgeons, Berlin 2006. No research grants funded this study.  相似文献   
49.
In 2002, the United Network for Organ Sharing proposed increasing the pool of donor kidneys to include Expanded Criteria Donor (ECD). Outside the USA, the ECD definition remains the one used without questioning whether such a graft allocation criterion is valid worldwide. We performed a meta‐analysis to quantify the differences between ECD and Standard Criteria Donor (SCD) transplants. We paid particular attention to select studies in which the methodology was appropriate and we took into consideration the geographical area. Thirty‐two publications were included. Only five studies, all from the USA, reported confounder‐adjusted hazard ratios comparing the survival outcomes between ECD and SCD kidney transplant recipients. These five studies confirmed that ECD recipients seemed to have poorer prognosis. From 29 studies reporting appropriate survival curves, we estimated the 5‐year pooled nonadjusted survivals for ECD and SCD recipients. The relative differences between the two groups were lower in Europe than in North America, particularly for death‐censored graft failure. It is of primary importance to propose appropriate studies for external validation of the ECD criteria in non‐US kidney transplant recipients.  相似文献   
50.
BK virus is a common opportunistic post‐transplantation viral infection. Although some risk factors have been studied in this context, the contribution of NK cells has not been assessed in detail. In a group of kidney transplant recipients, we studied the association between (i) the likelihood of BK virus replication during the two‐year period after kidney transplantation and (ii) the genotypes of the killer cell immunoglobulin‐like receptor (KIR) repertoire and their human leukocyte antigen (HLA) ligands. Other clinical factors (such as defective organ recovery and immunosuppressive treatment) were also assessed. BK virus replication was observed in 43 of the 103 recipients (41%). Patients with BK virus replication in the plasma were more likely to display defective organ recovery in the first seven days post‐transplantation. BK virus replication was not associated with Missing KIR ligands. However, BK virus replication was more frequent in patients with responsive NK cells (i.e. when a ligand for activating KIRs was not homozygous in the recipient and present in the donor). Our results suggest that defective organ recovery and the recipient's activating KIR repertoire may be related (depending on HLA ligands present in the couple recipient / donor) to the reactivation of BK virus replication after kidney transplantation.  相似文献   
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