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1.
Background: Nanotechnology is receiving greater attention these days as a result of its applications in numerous industrial, medical, and environmental fields. Objective: To synthesize silver nanoparticles with a green alga, Cladophora glomerata, and determine their inhibitory activity against tumor cell (MCF-7) and transgenic mouse cell (L20B) lines. Materials and Methods: Methanol extract was prepared from Cladophora glomerata and used as a safe factory for the synthesis of silver nanoparticles (AgNPs). UV-visible spectrophotometer, X-ray diffraction, scanning electron microscopy, and EDX analyses were used to characterize the biosynthesized AgNPs. The anti-tumor activity of the phycosynthesized AgNPs was tested against the MCF-7 and L20B cell lines. Furthermore, the bioactive compounds in the algal extract were determined by gas chromatography-mass spectroscopy (GC-MS). Results: The phycosynthesis produced clusters of spherical and polydispersed cuboidal pure AgNPs with an average size of 32 nm. The phycosynthesized AgNPs possess anti-cancer and anti-tumor activities on the MCF-7 and L20B cell lines, with significant anti-proliferation percentages of 52.8 and 65.8%, respectively, after 48 hours of treatment with 100 μg/ml AgNPs. Both treated cell lines showed a significant change in cellular shape and tissue detachment. The GC-MS analysis revealed the presence of a high proportion of octadecanoic acid (47.59%) and hexadecanoic acid (14.97%). Conclusion: Cladophora glomerata contains chemicals that improve the stabilization and reduction properties of the nanoparticles. It can be used as a safe, local, and natural source for the synthesis of AgNPs and can also be used as a benign factory for many other metal nanoparticles. The phycosynthesized AgNPs have anti-cancer and anti-tumor activities on the test cell lines and provide an insight into the potential for using them as a trend in cancer nanotherapy.  相似文献   
2.
Cancer‐associated glycosphingolipids have been used as markers for diagnosis and targets for immunotherapy of malignant tumors. Recent progress in the analysis of their implications in the malignant properties of cancer cells revealed that cancer‐associated glycosphingolipids are not only tumor markers, but also functional molecules regulating various signals introduced by membrane microdomains, lipid rafts. In particular, a novel approach, enzyme‐mediated activation of radical sources combined with mass spectrometry, has enabled us to clarify the mechanisms by which cancer‐associated glycosphingolipids regulate cell signals based on the interaction with membrane molecules and formation of molecular complexes on the cell surface. Novel findings obtained from these approaches are now providing us with insights into the development of new anticancer therapies targeting membrane molecular complexes consisting of cancer‐associated glycolipids and their associated membrane molecules. Thus, a new era of cancer‐associated glycosphingolipids has now begun.  相似文献   
3.
目的 探讨急性孤立性脑桥梗死(acute isolated pontine infarction,AIPI)神经功能缺损进展的危险 因素、病因分型及预后。 方法 回顾性分析2015年1月-2018年6月在西安交通大学第二附属医院神经内科住院的AIPI患者临 床资料,根据其是否存在神经功能缺损进展,将患者分为进展组与非进展组。记录两组患者一般资 料、病因分型、椎-基底动脉延长扩张症(vertebrobasilar dolichoectasia,VBD)的发生率及预后,通过多 元逻辑回归分析确定AIPI神经功能缺损进展的危险因素。 结果 最终纳入122例AIPI患者,进展组28例(23.0%),非进展组94例(77.0%)。进展组在糖尿病 患病率、入院时吞咽障碍发生率及出院时mRS评分均高于非进展组,差异具有统计学意义。进展组 病因分型中基底动脉分支动脉疾病(basilar artery branch disease,BABD)有16例(57.1%),小动脉疾病 (small artery disease,SAD)有2例(7.1%),大动脉闭塞性疾病(large artery occlusive disease,LAOD)有 10例(35.7%),进展组与非进展组差异有统计学意义(χ 2=8.739,P =0.013)。进展组VBD的发生率为 25.0%(7/28),高于非进展组的13.8%(13/94),但两组比较差异无统计学意义(P =0.267)。相比非 进展组,进展组不良预后比例显著增加(46.4% vs 10.6%,P <0.001)。Logistic回归分析显示,吞咽障 碍是AIPI神经功能缺损进展的独立危险因素(OR 4.610,95%CI 1.461~14.546,P =0.009)。 结论 AIPI的患者,当存在糖尿病、吞咽障碍、VBD、病因分型BABD时可能更容易出现神经功能缺损 进展;吞咽障碍是AIPI神经功能缺损进展的独立危险因素;发生神经功能缺损进展的AIPI患者预后 不良的发生率增高。  相似文献   
4.
目的氮素是中药材有效成分积累的重要影响元素,为探讨不同氮源对丹参Salviamiltiorrhiza和藏丹参Salvia castanea毛状根生长和活性成分积累的影响。方法分别采用硝酸铵、水解乳蛋白、蛋白胨、牛肉浸膏、酪蛋白和酵母提取物6种氮源处理对丹参和藏丹参毛状根的影响,分析毛状根生长及活性成分积累的变化。结果硝酸铵最有利于2种丹参毛状根的生长。水解乳蛋白能够显著促进丹酚酸类成分的积累,与硝酸铵对照相比,丹参迷迭香酸和丹酚酸B含量分别提高了2.94倍和3.27倍,藏丹参二者含量分别提高了13.74倍和2.01倍。酵母提取物对2种丹参毛状根二氢丹参酮Ι和隐丹参酮积累的促进效果最为显著,水解乳蛋白能显著促进丹参根中丹参酮IIA的积累,牛肉浸膏则对藏丹参中丹参酮IIA积累的促进作用最为显著。结论硝酸铵是2种丹参毛状根生长的最佳氮源,水解乳蛋白是丹酚酸积累的最佳氮源,不同氮源对4种丹参酮的影响不一致,丹参和藏丹参对不同氮源的响应也不一致。该研究不仅对丹参毛状根规模化培养及活性成分工业化生产具有一定指导意义,也对藏丹参资源的开发利用提供了借鉴作用。  相似文献   
5.
For decades it has been widely accepted that elective procedures should be delayed for at least 6-months following completion of isotretinoin therapy. However, numerous 2017 publications demonstrate the need for change in best practice. The evidence has yet to be succinctly summarized in a single article or in a stand-alone quick reference algorithm for physicians. This article’s review of all 2017 publications confirms that the 6-month delay is not necessary for all procedures and provides a simple algorithmic approach to summarize the updated recommendations for procedural delay of cosmetic procedures following systemic isotretinoin therapy. This is a useful tool for clinicians and allows patients to receive the most appropriate and timely cosmetic therapy to minimize the psychosocial impact of the skin condition.  相似文献   
6.
Acne vulgaris is a common condition which remains challenging to treat in some cases. Laser and light-based therapies offer an alternative to medical therapies with the advantage of high compliance and relatively low side-effect profile. Light-based therapies in acne exert their effects through photochemical, photothermal, or a combination of both mechanisms. This article explains the mode of action for each light-based modality and examines the current evidence in this field.  相似文献   
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BackgroundMolecular diagnostic methods have recently gained widespread use, and consequently, the importance of viral pathogens in community-acquired pneumonia (CAP) has undergone re-evaluation. Under these circumstances, the role of Chlamydophila pneumoniae as a pathogen that causes CAP also needs to be reviewed.MethodsWe reviewed articles that contained data on the frequency of identification of C. pneumoniae pneumonia as a causative pathogen for CAP. The articles were identified by performing a search in PubMed with the keywords “community-acquired pneumonia” and “pathogen”.ResultsSixty-three articles were identified. The reviewed articles demonstrated that the rates of identification of C. pneumoniae as the causative pathogen for CAP were significantly lower in assessments based on polymerase chain reaction (PCR) methods than in those based on serological methods. In some studies, it was possible to compare both serological and PCR methods directly using the same set of samples.ConclusionsThe use of PCR methods, including multiplex PCR assays, has revealed that C. pneumoniae may play a limited role as a pathogen for CAP.  相似文献   
10.
In its report on Carbohydrates and Health, the Scientific Advisory Committee on Nutrition (SACN) has recommended increases in the dietary reference values for fibre to 30 g/day for adults and 15–30 g/day for children, depending on their age. Intakes are currently much lower than this, at an average of 18 g/day in adults, less in children, and there are socio‐economic differences, with lower intakes in the lowest income quintile compared to the highest. Dietary modelling shows that achieving these recommendations is possible but will require substantial changes to dietary patterns for many, with meals based around fibre‐rich starchy foods (such as wholegrain and high‐fibre options of bread, breakfast cereals, pasta and rice, and jacket potatoes), supplemented by inclusion of high‐fibre snacks such as unsalted nuts and considerable amounts of vegetables and fruit, daily. This article discusses the challenges associated with communicating these new recommendations, in the context of current labelling legislation.  相似文献   
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