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11.

Background

We evaluated external ventricular drain placement for factors associated with placement accuracy. Data were acquired using an electronic health record data requisition tool.

Method

Medical records of all patients who underwent ventriculostomy from 2003 to 2010 were identified and evaluated. Patient demographics, diagnosis, type of guidance and number of catheter passes were searched for and recorded. Post-procedural hemorrhage and/or infection were identified. A grading scale was used to classify accuracy of catheter placements. A multiple logistic regression model was developed to assess features associated with accurate catheter placement.

Results

One hundred nine patients who underwent 111 ventriculostomies from 2003 to 2010 were identified. Patient diagnoses were classified into vascular (63 %), tumor (21 %), trauma (14 %), and cyst (2 %). Procedures were performed freehand in 90 (81 %), with the Ghajar guide in 17 (15 %), and with image guidance in 4 (4 %) patients. Eighty-eight (79 %) catheters were placed in the correct location. Trauma patients were more likely to have catheters misplaced (p?=?0.007) whereas patients in other diagnostic categories were not significantly associated with misplaced catheters. Post-procedural hemorrhage was noted in 2 (1.8 %) patients on post-procedural imaging studies. Five (4.5 %) definite and 6 (5.4 %) suspected infections were identified.

Conclusions

External ventricular drain placement can be performed accurately in most patients. Patients with trauma are more likely to have catheters misplaced. Further development is required to identify and evaluate procedure outcomes using an electronic health record repository.  相似文献   
12.
Lipoarabinomannan (LAM) is a critical virulence factor in the pathogenesis of Mycobacterium tuberculosis, the causative agent of tuberculosis. LAM is secreted in urine and serum from infected patients and is being studied as a potential diagnostic indicator for the disease. Herein, we present a novel ultra-sensitive and specific detection strategy for monomeric LAM based on its amphiphilic nature and consequent interaction with supported lipid bilayers. Our strategy involves the capture of LAM on waveguides functionalized with membrane mimetic architectures, followed by detection with a fluorescently labeled polyclonal antibody. This approach offers ultra-sensitive detection of lipoarabinomannan (10?fM, within 15?min) and may be extended to other amphiphilic markers. We also show that chemical deacylation of LAM completely abrogates its association with the supported lipid bilayers. The loss of signal using the waveguide assay for deacylated LAM, as well as atomic force microscopy (AFM) images that show no change in height upon addition of deacylated LAM support this hypothesis. Mass spectrometry of chemically deacylated LAM indicates the presence of LAM-specific carbohydrate chains, which maintain antigenicity in immunoassays. Further, we have developed the first three-dimensional structural model of mannose-capped LAM that provides insights into the orientation of LAM on supported lipid bilayers.  相似文献   
13.
PurposeAurora kinase B (AURKB) plays a pivotal role in the regulation of mitosis and is gaining prominence as a therapeutic target in cancers; however, the role of AURKB in retinoblastoma (RB) has not been studied. The purpose of this study was to determine if AURKB plays a role in RB, how its expression is regulated, and whether it could be specifically targeted.MethodsThe protein expression of AURKB was determined using immunohistochemistry in human RB patient specimens and immunoblotting in cell lines. Pharmacological inhibition and shRNA-mediated knockdown were used to understand the role of AURKB in cell viability, apoptosis, and cell cycle distribution. Cell viability in response to AURKB inhibition was also assessed in enucleated RB specimens. Immunoblotting was employed to determine the protein levels of phospho-histone H3, p53, p21, and MYCN. Chromatin immunoprecipitation–qPCR was performed to verify the binding of MYCN on the promoter region of AURKB.ResultsThe expression of AURKB was found to be markedly elevated in human RB tissues, and the overexpression significantly correlated with optic nerve and anterior chamber invasion. Targeting AURKB with small-molecule inhibitors and shRNAs resulted in reduced cell survival and increased apoptosis and cell cycle arrest at the G2/M phase. More importantly, primary RB specimens showed decreased cell viability in response to pharmacological AURKB inhibition. Additional studies have demonstrated that the MYCN oncogene regulates the expression of AURKB in RB.ConclusionsAURKB is overexpressed in RB, and targeting it could serve as a novel therapeutic strategy to restrict tumor cell growth.  相似文献   
14.
15.
The present study examined lexical representation in early Spanish‐English bilinguals using an unmasked semantic and translation priming paradigm. In Experiment 1, participants were divided into two groups based on performance (more‐balanced bilinguals, MB and less‐balanced bilinguals, LB) on the experimental task. In Experiment 2, four patients with bilingual aphasia (BA) performed the same experiment. Results from both experiments revealed that all groups were more accurate for English targets (S‐E direction) than Spanish targets (S‐E direction). In Experiment 1, semantic priming was observed from English to Spanish in both the LB and MB groups although the effect was greater for the LB group. Further, only the LB group showed priming from Spanish to English. For both normal groups, there was no difference between translation and semantic priming effects. In Experiment 2, patients with bilingual aphasia demonstrated different patterns of activation with no clear trends. Two participants demonstrated greater priming from Spanish to English whereas two participants demonstrated the opposite effect.  相似文献   
16.
Developing language treatments that not only improve trained items but also promote generalisation to untrained items is a major focus in aphasia research. This study is a replication and extension of previous work which found that training abstract words in a particular context-category promotes generalisation to concrete words but not vice versa (Kiran, Sandberg, & Abbott, 2009 Kiran, S., Sandberg, C., & Abbott, K. (2009). Treatment for lexical retrieval using abstract and concrete words in persons with aphasia: Effect of complexity. Aphasiology, 23, 835853. doi: 10.1080/02687030802588866[Taylor & Francis Online], [Web of Science ®] [Google Scholar]). Twelve persons with aphasia (five female) with varying types and degrees of severity participated in a generative naming treatment based on the Complexity Account of Treatment Efficacy (CATE; Thompson, Shapiro, Kiran, & Sobecks, 2003 Thompson, C., Shapiro, L., Kiran, S., & Sobecks, J. (2003). The role of syntactic complexity in treatment of sentence deficits in agrammatic aphasia: The Complexity Account of Treatment Efficacy (CATE). Journal of Speech, Language, and Hearing Research, 46, 591607. doi: 10.1044/1092-4388(2003/047)[Crossref], [PubMed], [Web of Science ®] [Google Scholar]). All participants were trained to generate abstract words in a particular context-category by analysing the semantic features of the target words. Two other context-categories were used as controls. Ten of the twelve participants improved on the trained abstract words in the trained context-category. Eight of the ten participants who responded to treatment also generalised to concrete words in the same context-category. These results suggest that this treatment is both efficacious and efficient. We discuss possible mechanisms of training and generalisation effects.  相似文献   
17.
To compare the clinical presentation and outcomes of retinoblastoma (RB) based on age at presentation. Retrospective comparative study of 1940 eyes of 1450 children with RB. Presentation of RB with enlarged eyeball and eyelid swelling (2% and < 1% in ≤ 1 year, 4% and 2% in > 1–2 years, 7% and 2% in > 2–3 years, and 12% and 4% in > 3 years; p < 0.0001 and p = 0.05, respectively) is more common with increasing age. Based on the 8th edition of American Joint Committee Classification, T1 is more common in children younger than 1 year (27%), while T4 is more common in children > 3 years of age (20%) (p < 0.0001). Kaplan–Meier (KM) estimate at 1 and 5 years for globe salvage was 64% and 58% in children ≤ 1 year of age versus 30% and 20% in children > 3 years, respectively [Hazard ratio (HR) = 2.48; p < 0.0001], and KM estimate at 1 and 5 years for life salvage was 99% and 97% in children ≤ 1 year of age versus 89% and 78% in children older than 3 years, respectively (HR = 7.65; p < 0.0001). Uncommon clinical features of RB including enlarged eyeball and eyelid swelling are more common with increasing age. Younger age at presentation with RB is associated with better prognosis including higher chances of life and globe salvage.  相似文献   
18.

Objectives

To compare the outcomes of initial one-stent (1S) versus dedicated two-stent (2S) strategies in complex bifurcation percutaneous coronary intervention (PCI) using everolimus-eluting stents (EES).

Background

PCI of true bifurcation lesions is technically challenging and historically associated with reduced procedural success and increased restenosis. Prior studies comparing initial one-stent (1S) versus dedicated two-stent (2S) strategies using first-generation drug-eluting stents have shown no reduction in ischemic events and more complications with a 2S strategy.

Methods

We performed a retrospective study of 319 consecutive patients undergoing PCI at a single referral center with EES for true bifurcation lesions, defined by involvement of both the main vessel (MV) and side branch (SB). Baseline, procedural characteristics, quantitative coronary angiography and clinical outcomes in-hospital and at one year were compared for patients undergoing 1S (n = 175) and 2S (n = 144) strategies.

Results

Baseline characteristics were well-matched. 2S strategy was associated with greater SB acute gain (0.65 ± 0.41 mm vs. 1.11 ± 0.47 mm, p < 0.0001). In-hospital serious adverse events were similar (9% with 2S vs. 8% with 1S, p = 0.58). At one year, patients treated by 2S strategy had non-significantly lower rates of target vessel revascularization (5.8% vs. 7.4%, p = 0.31), myocardial infarction (7.8% vs. 12.2%, p = 0.31) and major adverse cardiovascular events (16.6% vs. 21.8%, p = 0.21).

Conclusion

In this study of patients undergoing PCI for true coronary bifurcation lesions using EES, 2S strategy was associated with superior SB angiographic outcomes without excess complications or ischemic events at one year.  相似文献   
19.
20.
Two-component organogels offer several advantages over one-component gels, but their design is highly challenging. Hence, it is extremely important to design new approaches for the crafting of two-component organogels with interesting optical and mechanical properties. Herein, we report the design of a new class of two-component supergelators obtained from the assembly between acid functionalized tetraphenylethylene (TPE)-based dendrons and alkylated melamine. No gelation behaviour is observed for the individual components, but interestingly, remarkable gelation behaviour is observed for their hydrogen-bonded complex. The primary driving force responsible for the gelation is the strong π–π stacking interaction of TPE units. Because of the strong π-stacking of TPEs in the gel state, the C(sp2)–C(sp2) bond rotation of the TPE segment is completely arrested in the gel state, which results in intense fluorescence emission of the gels. Furthermore, excellent elastic response is observed for the gels as evident from their high storage modulus compared to loss modulus values. Our results clearly demonstrate that by the appropriate selection of the molecular components, this approach can be applied for the creation of functional nanomaterials with emergent properties absent in the individual blocks.

Design of a novel class of two-component, highly emissive, low molecular weight supergelator is reported.  相似文献   
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