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31.
We have developed a photoacoustics-based imaging system, the dual-scan mammoscope (DSM), that combines optical contrasts with acoustic detection, to obtain the angiographic features in human breast. In this study, we investigated whether the system can differentiate malignant tumor and healthy breast. We have imaged 38 patients with various tumor types and compared results of tumor-bearing breast with healthy breast for each patient. We also compared the photoacoustic and ultrasound imaging results with clinical US. Vascular features in and around the tumor mass were visualized. We found that tumor-bearing breast contained vessels of larger caliber and exhibited stronger variations in the background signals than those in the contralateral healthy breasts. Preliminary data on photoacoustic and ultrasound images also indicate that the technique has potential in differentiating different tumor types. Overall, our results indicate that combining photoacoustic and ultrasound images can improve breast cancer screening.  相似文献   
32.
We developed a novel integrative genomic tool called GRANITE (Genetic Regulatory Analysis of Networks Investigational Tool Environment) that can effectively analyze large complex data sets to generate interactive networks. GRANITE is an open-source tool and invaluable resource for a variety of genomic fields. Although our analysis is confined to static expression data, GRANITE has the capability of evaluating time-course data and generating interactive networks that may shed light on acute versus chronic treatment, as well as evaluating dose response and providing insight into mechanisms that underlie therapeutic versus sub-therapeutic doses or toxic doses. As a proof-of-concept study, we investigated lithium (Li) response in bipolar disorder (BD). BD is a severe mood disorder marked by cycles of mania and depression. Li is one of the most commonly prescribed and decidedly effective treatments for many patients (responders), although its mode of action is not yet fully understood, nor is it effective in every patient (non-responders). In an in vitro study, we compared vehicle versus chronic Li treatment in patient-derived lymphoblastoid cells (LCLs) (derived from either responders or non-responders) using both microRNA (miRNA) and messenger RNA gene expression profiling. We present both Li responder and non-responder network visualizations created by our GRANITE analysis in BD. We identified by network visualization that the Let-7 family is consistently downregulated by Li in both groups where this miRNA family has been implicated in neurodegeneration, cell survival and synaptic development. We discuss the potential of this analysis for investigating treatment response and even providing clinicians with a tool for predicting treatment response in their patients, as well as for providing the industry with a tool for identifying network nodes as targets for novel drug discovery.  相似文献   
33.
Valve repair in children is technically demanding but more desirable than valve replacement. From April 2004 to September 2005, 1 boy and 8 girls with rheumatic heart disease, aged 2-13 years (median, 9 years), underwent valve repair for isolated mitral regurgitation in 5, combined mitral and aortic regurgitation in 2, mitral stenosis in 1, and mitral regurgitation associated with atrial septal defect in 1. Chordal shortening in 7, annular plication in 6, commissurotomy in 1, reconstruction of commissural leaflets in 7 were performed for mitral valve disease. Plication and reattachment of the aortic cusps was carried out in 2 patients. Annuloplasty rings were not used. All patients survived the operation, 8 had trivial or mild residual mitral regurgitation, and 1 had trivial aortic regurgitation. Mean left atrial pressure decreased from 14 to 7 mm Hg postoperatively. During follow-up of 3-18 months, all children were asymptomatic and enjoyed normal activity. None required reoperation. In addition to chordal shortening and annular plication, reconstruction of the commissural leaflets is considered the most important aspect of valve repair. It can be achieved without annuloplasty rings, giving good early and midterm results.  相似文献   
34.
Success of the Clinical Translational Science Award (CTSA) program implicitly demands team science efforts and well‐orchestrated collaboration across the translational silos (T1–T4). Networks have proven to be useful abstractions of research collaborations. Networks provide novel system‐level insights and exhibit marked changes in response to external interventions, making them potential evaluation tools that complement more traditional approaches. This study is part of our ongoing efforts to assess the impact of the CTSA on Biomedical Research Grant Collaboration (BRGC). Collaborative research grants are a complex undertaking and an outcome of sustained interaction among researchers. In this report, BRGC networks representing collaborations among CTSA‐affiliated investigators constructed from grants management system data at the University of Kentucky across a period of six years (2007–2012) corresponding to pre‐ and post‐CTSA are investigated. Overlapping community structure detection algorithms, in conjunction with surrogate testing, revealed the presence of intricate research communities rejecting random graphs as generative mechanisms. The deviation from randomness was especially pronounced post‐CTSA, reflecting an increasing trend in collaborations and team‐science efforts potentially as a result of CTSA. Intercommunity cross talk was especially pronounced post‐CTSA.  相似文献   
35.
In present investigation, etiopathological characterization of upper gastrointestinal tract (GIT) tumours of cattle and buffaloes was undertaken. A total of 27 GIT wart‐like lesions in rumen, reticulum, mouth and oesophagus of cattle and buffaloes revealed the presence of small nodular to larger spherical or slender growths with thin base present on mucosa and ruminal pillar. Histopathologically, these cases were diagnosed as fibropapilloma/papilloma. This is the first world record on ruminal papillomatosis in buffaloes. Ruminal warts of cattle and buffaloes revealed the presence of BPV‐5, ‐1 & ‐2, which is the first report of presence of these BPVs in the ruminal warts from India. Quantitative real‐time PCR revealed that DNA samples of different GIT wart‐like lesions contained varying amount of BPV DNA copy numbers. Immunohistochemistry revealed that the PCNA and Ki67 immunopositivity was present in the basal and spinosum layer of the fibropapilloma/papilloma, indicating these as the cellular proliferation site. In conclusion, the present investigation revealed that BPV‐5, ‐1 & ‐2 are associated with certain ruminal wart‐like lesions/growths in cattle and buffaloes, and the basal and spinosum layer of the ruminal fibropapilloma/papilloma were cellular proliferation sites.  相似文献   
36.
In the present investigation, the effective root compound of plumbagin of Plumbago zeylanica (Plumbaginaceae) was evaluated for chemical constituent and antimalarial effect against the fourth instar larvae of Anopheles stephensi Liston (Diptera). In the chromatographic analyses of root compound with Rf value of 0.788 and NMR analyses also revealed that the effective compound contain naphthoquinone plumbagin were identified as the major chemical constituent. Larval mortality was observed after 3 h of exposure period. The plumbagin compound showed remarkable larvicidal activity against A. stephensi (LC50 32.65 and LC9072.27 ppm). Histopathological effects of compound was observed in the treated larvae. Based on the results, the plumbagin compound of P. zeylanica can be considered as a new source of natural larvicide for the control of malarial vector.  相似文献   
37.

Background and Aims:

Adequate nutritional support is crucial in prevention and treatment of malnutrition in critically ill-patients. Despite the intention to provide appropriate enteral nutrition (EN), meeting the full nutritional requirements can be a challenge due to interruptions. This study was undertaken to determine the cause and duration of interruptions in EN.

Materials and Methods:

Patients admitted to a multidisciplinary critical care unit (CCU) of a tertiary care hospital from September 2010 to January 2011 and who received EN for a period >24 h were included in this observational, prospective study. A total of 327 patients were included, for a total of 857 patient-days. Reasons and duration of EN interruptions were recorded and categorized under four groups-procedures inside CCU, procedures outside CCU, gastrointestinal (GI) symptoms and others.

Results:

Procedure inside CCU accounted for 55.9% of the interruptions while GI symptoms for 24.2%. Although it is commonly perceived that procedures outside CCU are the most common reason for interruption, this contributed only to 18.4% individually; ventilation-related procedures were the most frequent cause (40.25%), followed by nasogastric tube aspirations (15.28%). Although GI bleed is often considered a reason to hold enteral feed, it was one of the least common reasons (1%) in our study. Interruption of 2-6 h was more frequent (43%) and most of this (67.1%) was related to “procedures inside CCU”.

Conclusion:

Awareness of reasons for EN interruptions will aid to modify protocol and minimize interruptions during procedures in CCU to reach nutrition goals.  相似文献   
38.
An oxidant-free three-component synthesis of biologically significant 7-amino-6H-benzo[c]chromen-6-ones was established involving a Sc(OTf)3 catalyzed three-component reaction between primary amines, β-ketoesters and 2-hydroxychalcones under green conditions. In this strategy, both the B and C rings of 6H-benzo[c]chromen-6-ones were constructed simultaneously starting from acyclic precursors by generating four new bonds including two C–C, one C–N and one C–O in a single synthetic operation. The mechanism of this sequential cascade process involves the initial formation of a β-enaminone intermediate followed by Michael addition with 2-hydroxychalcone, intramolecular cyclization, dehydration, lactonization and aromatization steps. Unlike the related literature approaches, this reaction delivered the products without the addition of any external oxidants to achieve the key aromatization step.

Three-component synthesis of 7-amino-6H-benzo[c]chromen-6-ones was achieved under oxidant-free green conditions.  相似文献   
39.
2-(4-((2-Hydroxyethyl)(methyl)amino)benzylidene)malononitrile (HEMABM) was synthesized from 4-[hydroxymethyl(methyl)amino]benzaldehyde and propanedinitrile to obtain a low molecular weight fluorescent material with an efficient solid-state emission and electroluminescence properties comparable to the well-known poly(2-methoxy-5(2′-ethyl)hexoxyphenylenevinylene) (MEH-PPV). The HEMABM was used to prepare an organic light-emitting diode by a solution process. Despite the title compound being a small molecule, it showed optical properties and notable capacity to form a film with smooth morphology (10.81 nm) closer to that of polymer MEH-PPV (10.63 nm). The preparation of the device was by spin coating, the electrical properties such as threshold voltage were about 1.0 V for both HEMABM and MEH-PPV, and the luminance 1300 cd m−2 for HEMABM and 2600 cd m−2 for MEH-PPV. This low molecular weight compound was characterized by SCXRD, IR, NMR, and EI. Besides a quantitative analysis of the intermolecular interactions by PIXEL, density functional theory (DFT) calculations are reported.

A low molecular weight fluorescent malononitrile derivative showed an efficient solid-state emission and electroluminescence properties.  相似文献   
40.
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