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91.
《Expert opinion on drug delivery》2013,10(12):1681-1694
ABSTRACTIntroduction: Amorphous solid dispersions are considered as one of the most powerful strategies to formulate poorly soluble drugs. They are made up of an active pharmaceutical ingredient (API) dispersed at the molecular level in an amorphous polymeric carrier. As the latter component constitutes the largest part of the formulation, its characteristics will contribute to a large extent to the properties and behavior of the solid dispersion.Areas covered: Amorphous polymers are most often used in modern solid dispersion formulations. This review discusses carrier properties like molecular weight, conformation, hygroscopicity, their stabilization effects, issues related to solid dispersion manufacturing technology, response to downstream processing, and potential to generate supersaturation, next to criteria to select a carrier to formulate stable amorphous solid dispersions.Expert opinion: Different amorphous carriers lead to solid dispersions with various properties in terms of physical stability, phase behavior and drug release rate and extent. Despite more than 50 years of intensive research in this field it remains difficult to predict what carrier is best suited for a given API, pointing to the complex nature of this formulation strategy. Sustained efforts to understand the link and complex interplay between material properties, processing parameters, physical stability and dissolution behavior are required from pharmaceutical scientists with a strong physicochemical background to shift the development from trial and error to science driven. 相似文献
92.
目的 分析医院Ⅰ类切口手术抗菌药物预防性使用情况,加强Ⅰ类切口手术抗菌药物预防使用的控制和管理.方法 通过医院信息系统(HIS)统计2018年1-11月江苏省盐城市第一人民医院Ⅰ类切口手术数量和抗菌药物使用率,筛选出冠脉造影等血管介入诊断手术和重点监控Ⅰ类切口手术,统计其抗菌药物使用率,再通过电子信息化病历系统分析抗菌... 相似文献
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Thyrotropin-releasing hormone (TRH), 0.1 mg/kg, i.m., significantly counteracted pentobarbital narcosis in six monkeys, but melanocyte-stimulating-hormone-release-inhibiting factor (MIF), 0.1 mg/kg i.m., did not. Earlier dose-response studies in unanesthetized monkeys had shown that this dose of MIF stimulated motor activity; this dose of TRH had shown no stimulant effect, but a higher dose depressed activity. Thus, an MIF dose that stimulates unanesthetized monkeys does not reverse pentobarbital narcosis; a TRH dose that by itself is neither stimulant nor depressant does partially reverse pentobarbital narcosis. 相似文献
96.
目的:研究姜黄素和索拉非尼联合应用对人肾癌786-O 细胞株增殖的影响。方法采用 MTT 法观察姜黄素和索拉非尼对人肾癌细胞786-O 细胞株的抑制作用。结果姜黄素及索拉非尼能抑制人肾癌786-O 细胞株的增殖,并呈浓度及时间依赖性,两者作用人肾癌786-O 细胞株48 h 的半数抑制浓度( IC50)分别为29.2μmol/ L、6.5μmol/ L。姜黄素6.25μmol/ L、12.5μmol/ L、25μmol/ L、50μmol/ L 与索拉非尼1.5μmol/ L、3μmol/ L、6μmol/ L、12μmol/ L、联合24 h、48 h、72 h 的抑制率显著高于单用索拉非尼、姜黄素组( P ﹤0.05)。结论姜黄素在体外对人肾癌786-O 细胞株的增殖有明显的抑制作用,能提高索拉非尼对人肾癌786-O 细胞株的敏感性。 相似文献
97.
左旋门冬酰胺酶(L-ASP)作为儿童急性淋巴细胞白血病治疗联合化疗方案中的最基本药物之一,在对维持患儿长期处于带病生存状态中起着极为重要的作用。但长期以来其在儿童临床应用的安全性也一直是人们关注的重点。就近些年L-ASP在国内外儿童临床应用引起不良反应的类型、原因以及发展方向等方面的研究进展进行综述。 相似文献
98.
目的:以肾间质纤维化模型大鼠的肾功能及肾小管间质损伤指数改善为药理活性指标,对黄芪当归合剂(AA)进行分离和筛选,获得其肾脏保护作用的药物有效部位。方法:应用溶剂法和色谱法逐级对AA进行追踪分离,分别获得11个不同部位。同时将Wistar大鼠随机分为假手术组、单侧输尿管梗阻(UUO)模型组、AA组及不同部位治疗组。灌胃给药后观察AA各部位对UUO大鼠肾损伤的疗效。治疗10 d后经腹主动脉取血检测血清肌酐(Scr)和尿素(Urea)水平;同时观察梗阻侧肾脏的病理变化,并对肾间质细胞浸润、肾小管萎缩和肾间质纤维化等病理损伤的程度(PI-Ⅰ)进行半定量评分,以PI-Ⅰ改善作为主要疗效、肾功能改善作为次要疗效,筛选获得具有最佳药理活性的有效部位。结果:在溶剂法分离获得的7个不同极性部位中,组分I和IC均具有改善肾功能、减轻肾小管间质损伤的疗效,其肾脏保护作用与AA疗效相近;而色谱法分离IC得到的4个部位对Scr,Urea及PI-I均无改善作用。结论:在UUO大鼠模型中,源自复方中药AA的组分I和IC具有与原方剂相似,具有抑制肾间质纤维化的作用,可确认为AA肾脏保护作用的有效部位。 相似文献
99.
Yuqin Zhang Wei Xu Huang Li Xun Zhang Yufa Xia Kedan Chu Lidian Chen 《Journal of ethnopharmacology》2013
Ethnopharmacological relevance
Tripterygium wilfordii Hook f. is one of Traditional Chinese Medicines which is commonly used to treat rheumatoid arthritis (RA). The total alkaloids were the main constituent part of Tripterygium wilfordii Hook f. It has a great significance to study the effects of the total alkaloids of Tripterygium wilfordii Hook f. (ATW) on RA.Aim of the study
This paper aims at investigating the therapeutic effect of ATW on RA and its possible mechanism, and providing a theoretical and experimental basis for the clinical use of ATW.Materials and methods
The model of wistar rats of type II collagen-induced arthritis (CIA) was made, and the rats were perfused a stomach with ATW for 4 weeks continuously. Then the levels of interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-<alpha>, in the serum of CIA rats were detected by enzyme linked immunosorbent assay (ELISA), and the joint pathological section of CIA rats was observed by hematoxylin and eosin (HE) staining method and the expression of IL-6, IL-8, nuclear factor kappa B (NF-κB), TNF-α were measure by immunohistochemistry staining method.Results
Compared with model group, ATW could significantly reduce paw swelling and suppresse articular cartilage degenerated. The results also found that there was significant reduction levels of IL-6, IL-8 and TNF-α in serum of CIA rats treated with ATW and ATW inhibited the expression of IL-6, IL-8, NF-κB, TNF-α in synovial tissue.Conclusion
ATW not only could inhibit the symptom of CIA rats significantly but also could inhibit the production of IL-6, IL-8, TNF-α in serum and the expression of IL-6, IL-8, NF-κB and TNF-α in synovial tissue targeting the inflammatory. ATW would be a drug as a novel botanical drug for the treatment of RA. 相似文献100.
AIM OF THE STUDY: Chi-Zhi-Huang decoction (PGR) is one of the traditional Chinese medicine (TCM) preparations with unique effect on withdrawing jaundice and has been used to treat icteric patients in China for many years. In this research, we aim at to evaluate the potential activity of PGR in restoring hepatic drug metabolism in a damaged liver. MATERIALS AND METHODS: A cocktail approach with caffeine (10mg/kg), dapsone (10mg/kg) and chlorzoxazone (20mg/kg) respectively as probe drug of cytochrome P450 (CYP) isoform of CYP 1A2, 3A4 and 2E1 was used to evaluate its possible effects on Phase I oxidative metabolism. Pretreated with three dosages of PGR water extract (0.75, 1.5 and 3g/kg, po) for 5 days, male Wistar rats (220-240 g) were intoxicated by phenylisothiocyanate (PITC, 100mg/kg, po) 24h before probes intravenous injection. The pharmacokinetics of the probes in the blood was determined simultaneously by HPLC, and their non-compartmental parameters were used to evaluate the metabolic difference among the groups. Moreover, the levels of liver enzymes (ALT, AST, ALP) and bilirubins were also measured for insight of liver function. RESULTS: The findings in this study suggest that PGR induces CYP 3A4, does not have much effect on CYP 2E1, and inhibits CYP 1A2 at high dosage. CONCLUSION: The current pharmacokinetic approach allowed the protective effects of PGR on oxidative drug metabolism in damaged liver to be systemically examined and will certainly help in the explanation of synergistic effect of the composites formula. 相似文献