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111.

Background

Laparoscopic major hepatectomy (LMH), although safely feasible in experienced hands and in selected patients, is a formidable challenge because of the technical demands of controlling hemorrhage, sealing bile ducts, avoiding gas embolism, and maintaining oncologic surgical principles. The enhanced surgical dexterity offered by robotic assistance could improve feasibility and/or safety of minimally invasive major hepatectomy. The aim of this study was to compare perioperative outcomes of LMH and robotic-assisted major hepatectomy (RMH).

Methods

Pooled data from four Italian hepatobiliary centers were analyzed retrospectively. Demographic data, operative, and postoperative outcomes were collected from prospectively maintained databases and compared.

Results

Between January 2009 and December 2012, 25 patients underwent LMH and 25 RMH. The two groups were comparable for all baseline characteristics including type of resection and underlying pathology. Conversion to open surgery was required in one patient in each group (4 %). No difference was noted in operative time, estimated blood, and need for allogenic blood transfusions. Intermittent pedicle occlusion was required only in LMH (32 % vs. 0; p = 0.004). Length of hospital stay, including time spent in intensive care unit, was similar between the two groups, but patients undergoing LMH showed quicker recovery of bowel activity, with shorter time to first flatus (1 vs. 3 days; p = 0.023) and earlier tolerance to oral liquid diet (1 vs. 2 days; p = 0.001). No difference was noted in complication rate, 90-day mortality, and readmission rate.

Conclusions

This retrospective multi-institution study confirms that selected patients can safely undergo minimally invasive major hepatectomy, either LMH or RMH. The fact that intermittent pedicle occlusion could be avoided in RMH suggests improved surgical ability to deal with bleeding during liver transection, but further studies are needed before any final conclusion can be drawn.  相似文献   
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This investigation analyzed the immunoexpression of FasL, Fas, cleaved caspase-8, and cleaved caspase-3 in glioblastomas. Formalin-fixed and paraffin-embedded glioblastoma tissues and control brain tissues from 97 patients were analyzed by tissue microarrays and immunohistochemistry. Patients with glioblastomas that were negative or weakly stained (<50% of cells positive) for cleaved caspase-8 had worse cancer-specific overall survival (median = 8.5 months) than did patients with tumors that highly expressed cleaved caspase-8 (median = 11.7 months; P = 0.0325), independent of clinical variables. There was no association of other markers with survival, treatment, sex, age, tumor size, and primary site. Among the tumors, there were reasonable to good positive correlations between the expression of FasL and Fas (r = 0.47) and between Fas and cleaved caspase-8 (r = 0.41), and there were poor positive correlations between Fas and cleaved caspase-3 (r = 0.26), FasL and cleaved caspase-8 (r = 0.22), and cleaved caspase-8 and -3 (r = 0.31). Our results suggest that Fas-Fas-ligand signal transduction could be inhibited, especially at the stage of caspase-8 activation, thereby establishing a major mechanism for evasion of apoptosis by these tumors. The absence or low expression of cleaved caspase-8 in the tumors was a negative prognostic indicator for patient survival.  相似文献   
115.

OBJECTIVES

: To evaluate the neuroprotective effect of epidural hypothermia in rats subjected to experimental spinal cord lesion.

METHODS:

Wistar rats (n = 30) weighing 320-360 g were randomized to two groups (hypothermia and control) of 15 rats per group. A spinal cord lesion was induced by the standardized drop of a 10-g weight from a height of 2.5 cm, using the New York University Impactor, after laminectomy at the T9-10 level. Rats in the hypothermia group underwent epidural hypothermia for 20 minutes immediately after spinal cord injury. Motor function was assessed for six weeks using the Basso, Beattie and Bresnahan motor scores and the inclined plane test. At the end of the final week, the rats'' neurological status was monitored by the motor evoked potential test and the results for the two groups were compared.

RESULTS:

Analysis of the Basso, Beattie and Bresnahan scores obtained during the six-week period indicated that there were no significant differences between the two groups. There was no significant difference between the groups in the inclined plane test scores during the six-week period. Furthermore, at the end of the study, the latency and amplitude values of the motor evoked potential test were not significantly different between the two groups.

CONCLUSION:

Hypothermia did not produce a neuroprotective effect when applied at the injury level and in the epidural space immediately after induction of a spinal cord contusion in Wistar rats.  相似文献   
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Lynch syndrome, or hereditary nonpolyposis colon cancer (HNPCC), is an autosomal-dominant disease accounting for approximately 1–5% of all colorectal cancer cases. Due to the lack of pathognomonic morphological or biomolecular markers, HNPCC has traditionally posed unique problems to clinicians and geneticists alike, both in terms of diagnosis and clinical management. Recently, novel insight into the pathogenesis of this syndrome has been provided by the identification of its molecular basis. In HNPCC families, germline mutations in any of four genes encoding proteins of a specialized DNA repair system, the mismatch repair, predispose to cancer development. Mutations in mismatch repair genes lead to an overall increase of the mutation rate and are associated with a phenotype of length instability of microsatellite loci. The present report summarizes the clinicopathological aspects of HNPCC and reviews the most recent molecular and biochemical findings. © 1996 Wiley-Liss, Inc.  相似文献   
118.
Ionotropic glutamate (Glu) receptors of the N-methyl-D-aspartate type (NMDA) play a fundamental role in many cortical functions. Native NMDA receptors are composed of a heteromeric assembly of different subunits belonging to two classes: NMDAR1 (NR1) and NMDAR2 (NR2). To date, NMDA receptors are believed to be expressed only in neurons, although electrophysiological and in situ hybridization studies have suggested that this class of Glu receptors might be also expressed by some astrocytes. In this study, we have investigated in the cerebral cortex of adult rats the presence of astrocytes expressing NR1 and NR2A/B subunits by immunocytochemistry with specific antibodies, and we show that some distal astrocytic processes, but only rarely astrocytic cell bodies, contain immunoreaction product indicative of NR1 and NR2A/B expression. These findings suggest that at least part of the role NMDA has in cortical functions might depend on the activation of astrocytic NMDA receptors; the subcellular localization of NR1 and NR2A/B subunits in distal processes suggests that NMDA receptors contribute to monitoring Glu levels in the extracellular space. © 1996 Wiley-Liss, Inc.  相似文献   
119.
Objectives:To investigate whether lesion imaging features may condition the outcome of CT-guided lung biopsy (CTLB) and to develop a scoring system of biopsy outcome prediction.Methods:This is a single center retrospective study on 319 CTLBs that were performed in 319 patients (167 males/152 females, mean age 68 ± 12.2). Uni- and multivariate analysis were performed aiming to assess the imaging features that are likely to be correlated to a negative biopsy outcome and patients were stratified in groups accordingly.Results:Technical success was 100%. 78% of the biopsies (250/319) led to a concrete histology report (218 malignant/32 benign). The remaining lesions led to concrete histology at a second attempt that occurred on a later time. Multivariate analysis revealed increased risk of inconclusive result for nodules with low fludeoxyglucose uptake [odds ration (OR) = 2.64, 95% confidence interval (CI) 1.4–4.97; p = 0.003], for nodules with diameter smaller than 18 mm (OR = 2.03, 95% CI 1.14–3.62; p = 0.017) and for nodules that are located in one of the lung bases (OR = 1.96, 95% CI 1.06–3.62; p = 0.033). Three different groups of patients were identified accordingly with low (<30%), medium (30–50%) and high (>50%) probability of obtaining an inconclusive biopsy sample.Conclusion:This study confirms that percutaneous CT-guided biopsy in nodules that are either small in diameter or present low positron emission tomography-fludeoxyglucose uptake or are in one of the lung bases may lead to inconclusive histology. This information should be factored when planning percutaneous biopsies of such nodules in terms of patient informed consent and biopsy strategy.Advances in knowledge:Inconclusive histology after lung biopsy may be subject to factors irrelevant to technical success. Lung biopsy histology outcomes may be predicted and avoided after adequate planning.  相似文献   
120.
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