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671.

Background

Biological monitoring of healthy workers exposed to hazardous dusts lack validated screening tools. Induced sputum (IS) cellular profile was compared with bronchoalveolar lavage fluid (BALF) profile in asbestos exposed workers in order to assess its usefulness in monitoring workers exposed to asbestos for a long period of time.

Methods

IS and BALF analysis was performed in 39 workers of a car brakes and clutches factory that uses chrysotile asbestos. Selection criteria were an employment history of > 15 years and the absence of a diagnosis of pneumonoconiosis. The type of cells, the existence of dust cells, of iron laden macrophages and of asbestos bodies were assessed and compared between IS and BALF samples.

Results

35 IS samples (90%) had dust cells, 34 (87%) iron laden macrophages and in 8 samples (21%) asbestos bodies were found. In most samples neutrophils were dominated. Samples with asbestos bodies (ABs) had significantly higher lymphocytes and lower neutrophils count compared with the samples without ABs. Macrophages and neutrophils in IS and BALF exhibited significant inter-relations (Spearman's rho: 0.26-0.29, p < 0.05) while IS lymphocytes count showed an inverse relation with BALF neutrophils (Spearman's rho: -0.36). Neutrophils and dust cells were highly correlated between the samples (Spearman's rho: 0.35, p < 0.05) while IS dust cells and lymphocytes were inversely related (Spearman's rho: -0.36, p < 0.05). More years of employment in the company was related with more neutrophils (Spearman's rho: 0.26) and less lymphocytes (Spearman's rho: -0.33) count. In multivariate analysis the presence of AB in IS samples was strongly related to the presence of asbestos bodies and lymphocytes count in BALF samples.

Conclusions

IS and BALF analysis showed a similar cellular profile indicating that IS sampling in exposed workers to asbestos as a less invasive and expensive method may be useful in providing an insight both for inhalation of dusts and inflammatory processes in the lung.  相似文献   
672.

Introduction

Streptococcus intermedius - a member of the Streptococcus anginosus group - is part of the normal microbial flora of the oral cavity. Despite being regarded as a harmless apathogenic commensal, Streptococcus intermedius has been described to cause abscesses in various locations of the body.

Case Presentation

We report the clinical case and course of treatment of a 18-year-old male patient presenting with multiple hepatic abscesses associated with an untreated pyogenic dental infection.

Conclusion

Streptococcus intermedius can cause liver abscesses emerging from dental infectious foci even in previously healthy patients without underlying innate or aquired immunodeficiency. The case illustrates the potential danger and underestimated risk associated with untreated dental infections.  相似文献   
673.

INTRODUCTION

The concept of using a mesh to repair hernias was introduced over 50 years ago. Mesh repair is now standard in most countries and widely accepted as superior to primary suture repair. As a result, there has been a rapid growth in the variety of meshes available and choosing the appropriate one can be difficult. This article outlines the general properties of meshes and factors to be considered when selecting one.

MATERIALS AND METHODS

We performed a search of the medical literature from 1950 to 1 May 2009, as indexed by Medline, using the PubMed search engine (<http://www.pubmed.gov>). To capture all potentially relevant articles with the highest degree of sensitivity, the search terms were intentionally broad. We used the following terms: ‘mesh, pore size, strength, recurrence, complications, lightweight, properties’. We also hand-searched the bibliographies of relevant articles and product literature to identify additional pertinent reports.

RESULTS AND CONCLUSIONS

The most important properties of meshes were found to be the type of filament, tensile strength and porosity. These determine the weight of the mesh and its biocompatibility. The tensile strength required is much less than originally presumed and light-weight meshes are thought to be superior due to their increased flexibility and reduction in discomfort. Large pores are also associated with a reduced risk of infection and shrinkage. For meshes placed in the peritoneal cavity, consideration should also be given to the risk of adhesion formation. A variety of composite meshes have been promoted to address this, but none appears superior to the others. Finally, biomaterials such as acellular dermis have a place for use in infected fields but have yet to prove their worth in routine hernia repair.  相似文献   
674.
ATP-binding cassette transporter ABCG2 [breast cancer resistance protein (BCRP)] is a member of the ABC transporter superfamily that actively extrudes xenotoxins from cells and is a major determinant of the bioavailability of many compounds. ABCG2 expression is strongly induced during lactation in the mammary gland and is related to the active secretion of drugs into the milk. The presence of drug residues and environmental pollutants in milk is an outstanding problem for human milk consumption and milk industrial processes, involving important risks to public health and the dairy industry. In cows, a single nucleotide polymorphism (SNP) in this protein has been described previously (Tyr581) and is associated with higher fat and protein percentages and lower milk yield. However, whether this amino acid substitution affects ABCG2-mediated drug transport in cows, including milk secretion, required further exploration. We cloned the two variants of bovine ABCG2 and evaluated the effect of this SNP on mitoxantrone accumulation assays performed in ovine primary fibroblasts transiently expressing either of the variants. It is interesting to note that statistically significant differences in activity between both variants were observed, and the Ser581 variant was related with an increased efflux activity. In addition, we demonstrated that genistein is a very good inhibitor of bovine ABCG2 and identified new inhibitors of the transporter, such as the macrocyclic lactones, ivermectin, and selamectin. Moreover, the inhibitory effect of these compounds on human and murine ABCG2 homologs was confirmed using transduced Marbin-Dabin canine kidney II cells. These findings may have important implications regarding the presence of drug residues in milk and drug interactions affecting the pharmacological behavior of ABCG2 substrates.  相似文献   
675.
Barriers obstructing evidence‐based nursing have been explored in many countries. Lack of resources and evidence has been noted as one of these barriers. We aimed to identify nursing care‐related systematic reviews published in the Cochrane Database of Systematic Reviews from 1996 until 2009. Using a broad search strategy we identified titles of Cochrane systematic reviews and protocols that focused on nursing care. The abstract of each title was examined and predetermined data were collected and analysed. 1249 titles out of a possible 6244 records were identified as being relevant to nursing care. Most of them focused on newborn and adult populations and related to comparing one intervention with another, and management strategies. The most common nursing specialties represented were internal medicine (34%) and mother and child care (25%). Twenty one percent of reviews published in the Cochrane Database of Systematic Reviews are of direct interest to those involved in nursing care however their relevance was not always obvious.  相似文献   
676.
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