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41.
载三氧化二砷纳米微粒对胰腺癌腹水抑制效应的实验研究 总被引:1,自引:0,他引:1
目的探讨用纳米载体包裹的三氧化二砷(As2O3)在荷胰腺癌SCID小鼠体内的分布及对腹水生成和存活时间的影响。方法用超声乳化法制备载As2O3乳酸羟基乙酸共聚物纳米微粒(As2O3-NPs),用体外释药方法研究其释放特性。于小鼠右前腋下接种SW1990细胞12d后,静脉给As2O3-NPs5.0mg/kg体重,采用高压液相色谱法(HPLC)测定血浆、正常和肿瘤组织中As2O3含量。观察不同浓度As2O3-NPs对腹水生成的抑制作用。观察10.0mg/kg体重As2O3-NPs处理的胰腺癌小鼠的存活期、体重、腹腔渗透性及腹水中凋亡细胞的变化。结果As2O3-NPs直径为(210±23)nm,含药量为29%(重量比),体外释药速度明显慢于单纯的As2O3。As2O3-NPs在体内呈浓度依赖性抑制腹水形成,减少腹膜的通透性,增加腹水内凋亡细胞量,延长荷瘤小鼠的存活时间。结论As2O3-NPs具有明显的缓释药物功能,能有效积聚在肿瘤组织,并抑制癌性腹水生成,是一种有希望的抗肿瘤药物。 相似文献
42.
Vinicius Rosa Dean Ho Robinson Sabino-Silva Walter L. Siqueira Nikolaos Silikas 《Dental materials》2021,37(3):496-507
ObjectiveViruses on environmental surfaces, in saliva and other body fluids represent risk of contamination for general population and healthcare professionals. The development of vaccines and medicines is costly and time consuming. Thus, the development of novel materials and technologies to decrease viral availability, viability, infectivity, and to improve therapeutic outcomes can positively impact the prevention and treatment of viral diseases.MethodsHerein, we discuss (a) interaction mechanisms between viruses and materials, (b) novel strategies to develop materials with antiviral properties and oral antiviral delivery systems, and (c) the potential of artificial intelligence to design and optimize preventive measures and therapeutic regimen.ResultsThe mechanisms of viral adsorption on surfaces are well characterized but no major breakthrough has become clinically available. Materials with fine-tuned physical and chemical properties have the potential to compromise viral availability and stability. Emerging strategies using oral antiviral delivery systems and artificial intelligence can decrease infectivity and improve antiviral therapies.SignificanceEmerging viral infections are concerning due to risk of mortality, as well as psychological and economic impacts. Materials science emerges for the development of novel materials and technologies to diminish viral availability, infectivity, and to enable enhanced preventive and therapeutic strategies, for the safety and well-being of humankind. 相似文献
43.
《Pediatric Dental Journal》2021,31(3):256-267
ObjectivesThis study aimed to assess the color change of primary teeth following exposure to an experimentally synthesized liposomal nano-encapsulated ferrous sulfate drop compared with the commercially iron drops.Materials and methodsIn this in-vitro study, liposomal nano-encapsulated ferrous sulfate (lipo-nano-ferr) drop was first synthesized. Next, 110 extracted primary anterior teeth were randomized into two equal groups (sound and demineralized). Each group was randomly divided into 5 subgroups (n = 11) and exposed to Irofant, Feroglobin, Sideral, and lipo-nano-ferr drops for 540 cycles. One subgroup was remained in artificial saliva as the negative control. Tooth color was analyzed before and after the interventions visually, and the rate of iron adsorption was analyzed by atomic absorption spectrometry (AAS), and energy-dispersive X-ray spectroscopy/scanning electron microcopy (EDS/SEM). Data were analyzed using t-test, one-way ANOVA, and LSD test.ResultsIron adsorption was significantly higher by the demineralized specimens than the sound specimens in all subgroups (P < 0.001). A significant difference was noted in iron adsorption among the four subgroups in each of the sound and demineralized groups (P < 0.001). Iron adsorption in the lipo-nano-ferr subgroup was significantly lower than that in Irofant and Feroglobin groups (P < 0.001). The visual inspection results were similar to AAS results. EDS-SEM showed that the atomic percentage of iron in Sideral and lipo-nano-ferr groups was significantly lower than that in Irofant and Feroglobin groups (P < 0.001).ConclusionUse of nano-encapsulation technology in production of iron drops can significantly decrease the resultant tooth discoloration, causing a clinically negligible color change. 相似文献
44.
BackgroundDental caries results from long-term acid production when sugar is metabolized by a bacterial biofilm, resulting in a loss of calcium and phosphate from the enamel. Streptococcus mutans is a type of acid-producing bacteria and a virulent contributor to oral biofilms. Conventional treatment options, such as cefazolin and ampicillin, have significant levels of bacterial resistance. Other topical agents, such as fluoride, tend to be washed away by saliva, resulting in low therapeutic efficacy.HighlightThis review aims to highlight the solubility issues that plague poorly water-soluble therapeutic agents, various novel polymeric, and lipid-based nanotechnology systems that aim to improve the retention of therapeutic agents in the oral cavity.ConclusionIn this review, different formulation types demonstrated improved therapeutic outcomes by enhancing drug solubility, promoting penetration into the deep layers of the biofilm, facilitating prolonged residence time in the buccal cavity, and reducing the emergence of drug-resistant phenotypes. These formulations have a strong potential to give new life to therapeutic agents that have limited physicochemical characteristics. 相似文献
45.
IntroductionDental implants are a usual treatment for the loss of teeth. The success of this therapy is due to the predictability, safety and longevity of the bone–implant interface. Dental implant surface characteristics like roughness, chemical constitution, and mechanical factors can contribute to the early osseointegration. The aim of the present article is to perform a review of the literature on surface roughness of dental implant and osseointegration.MethodologyThis work is a narrative review of some aspects of surface roughness of dental implant and osseointegration.ConclusionDespite technological advancement in the biomaterials field, the ideal surface roughness for osseointegration still remains unclear. In this study about surface nanoroughness of dental implant and osseointegration, the clinical relevance is yet unknown. Innovative findings on nanoroughness are valuable in the fields of dental implantology, maxillofacial or orthopedic implant surfaces and also on cardiovascular implants in permanent contact with patient’s blood. 相似文献
46.
《Biomaterials》2015
An important aspect in the design of nanomaterials for delivery is an understanding of its uptake and ultimate release to the cytosol of target cells. Real-time chemical sensing using a nanoparticle-based platform affords exquisite insight into the trafficking of materials and their cargo into cells. This versatile and tunable technology provides a powerful tool to probe the mechanism of cellular entry and cytosolic delivery of a variety of materials, allowing for a simple and convenient means to screen materials towards efficient delivery of therapeutics such as nucleic acids. 相似文献
47.
《Biomaterials》2015
Mitochondrial genome-targeting nucleic acids are promising therapeutic candidates for treating mitochondrial diseases. To date, a number of systems for delivering genetic information to the cytosol and the nucleus have been reported, and several successful gene therapies involving gene delivery targeted to the cytosol and the nucleus have been reported. However, much less progress has been made concerning mitochondrial gene delivery systems, and mitochondrial gene therapy has never been achieved. Here, we report on the mitochondrial delivery of an antisense RNA oligonucleotide (ASO) to perform mitochondrial RNA knockdown to regulate mitochondrial function. Mitochondrial delivery of the ASO was achieved using a combination of a MITO-Porter system, which contains mitochondrial fusogenic lipid envelopes for mitochondrial delivery via membrane fusion and D-arm, a mitochondrial import signal of tRNA to the matrix. Mitochondrial delivery of the ASO induces the knockdown of the targeted mitochondria-encoded mRNA and protein, namely cytochrome c oxidase subunit II, a component of the mitochondrial respiratory chain. Furthermore, the mitochondrial membrane potential was depolarized by the down regulation of the respiratory chain as the result of the mitochondrial delivery of ASO. This finding constitutes the first report to demonstrate that the nanocarrier-mediated mitochondrial genome targeting of antisense RNA effects mitochondrial function. 相似文献
48.
贾懿劼 《中国骨质疏松杂志》2012,18(2):188-192
目的旨在探究通过纳米骨组织材料治疗骨质疏松的进展,以促进其临床应用。方法由第一作者应用计算机检索PubMed、中国期刊全文数据库(CNKI)1997-05~2011-10相关文献。在标题、摘要、关键词中以"nano,osteoporosis,bone marrow mesenchymal stem cells(BMMSCs),treatment"或"纳米,骨质疏松,骨髓间充质干细胞,治疗"为检索词进行检索。选择文章内容与纳米技术治疗骨质疏松有关者,同一领域文献则选择近期发表在权威杂志文章。结果初检得到127篇文献,根据纳入标准选择36篇文献进行综述。结论纳米技术治疗骨质疏松已经成为骨质疏松治疗中的一项新兴技术。目前通过纳米技术治疗骨质疏松主要通过促进药物吸收,维持药物作用时间,增加药物靶向性,促进干细胞分化的机制来进行骨质疏松的治疗。目前常用的技术包括药物纳米化,纳米微载体,材料表面纳米化,纳米材料修饰干细胞等。但目前纳米技术治疗骨质疏松尚未成熟,仍有许多问题有待解决。 相似文献
49.
50.
Amani Mohammed Basudan 《Saudi Dental Journal》2022,34(8):669
IntroductionPeriodontitis is a chronic inflammatory disease, resulting due to host immune response against subgingival biofilm. Most conventional treatment protocols aim to control the subgingival biofilm by mechanical means, such as dental scaling and root planning, and frequently accompanied by antibacterial co‐adjuvant therapies, including antibiotics, antiseptics, or probiotics. Local drug delivery facilitates administration of a lower dose of the drug to the target site, but at higher concentration, thereby reducing systemic adverse effects and toxicity. The present systematic review was conducted with the aim of identifying and reporting nanoparticle based periodontal drug delivery systems, with a specific focus on current trends and future perspectives in this field.Materials & methodsComprehensive literature search, restricted to published reports in English language between January 2000 and February 2022, was done electronically and manually. Search queries were addressed to the following electronic databases including, PubMed (MEDLINE), Science Direct (Elsevier), Cochrane Library, Web of Science (Clarivate Analytics) and Scholar (Google). Database search returned 780 results which were screened based on title, author names and publication dates, to identify 13 studies fulfilling the review criteria.ResultsData from the 13 included studies were reviewed and tabulated, elaborating the type of nanoparticle used, drug delivered and tissues/cells/subcellular components targeted by periodontal drug delivery. While majority of the studies were conducted in vitro, there were 3 in vivo studies and 3 clinical studies. Using nanotechnology for drug delivery resulted in better inhibition of bacterial growth, inflammatory modulation favoring resolution of periodontitis and capability for early tissue regeneration.ConclusionRecent developments in nanotechnology have enabled targeted local delivery of drugs and anti-inflammatory biomolecules, in synergy with nanoparticles, towards periodontal pathogens, inflammatory cells and periodontal tissues. Further research evaluating clinical periodontal disease management through nanoparticle based local drug delivery drugs is highly recommended. 相似文献