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111.
The antimalarial drug chloroquine has been suggested as a treatment for Ebola virus infection. Chloroquine inhibited virus replication in vitro, but only at cytotoxic concentrations. In mouse and hamster models, treatment did not improve survival. Chloroquine is not a promising treatment for Ebola. Efforts should be directed toward other drug classes.  相似文献   
112.
Macrolide-resistant Mycoplasma pneumoniae (MRMP) is highly prevalent in Asia and is now being reported from Europe. Few data on MRMP are available in the United States. Using genotypic and phenotypic methods, we detected high-level MRMP in 13.2% of 91 M. pneumoniae­–positive specimens from 6 US locations.  相似文献   
113.
The Healthcare-Associated Infections Community Interface (HAIC), launched in 2009, is the newest major activity of the Emerging Infections Program. The HAIC activity addresses population- and laboratory-based surveillance for Clostridium difficile infections, candidemia, and multidrug-resistant gram-negative bacilli. Other activities include special projects: the multistate Healthcare-Associated Infections and Antimicrobial Use Prevalence Survey and projects that evaluate new approaches for improving surveillance. The HAIC activity has provided information about the epidemiology and adverse health outcomes of health care–associated infections and antimicrobial drug use in the United States and informs efforts to improve patient safety through prevention of these infections.  相似文献   
114.
目的了解某省各级医疗机构甲状腺手术围手术期抗菌药物预防使用情况。方法对2011年1月1日—2013年12月31日该省各类甲状腺手术进行目标性监测,并对调查结果进行分析。结果共调查1 304例甲状腺手术,1 294例(99.23%)为择期手术;手术持续时间≤2 h者1 051例,占80.60%;抗菌药物使用率为96.70%;术前30 min给药者196例,占15.54%;抗菌药物使用时间48 h者887例,占70.34%;使用第一代头孢、克林霉素的占19.53%。结论该省甲状腺手术中存在抗菌药物选择不当、用药时机不当、用药时间过长、无指征用药现象等问题,应加大抗菌药物管理力度,促进抗菌药物合理使用。  相似文献   
115.
目的研究1株柳珊瑚共附生真菌具有抑菌活性次级代谢产物及抑菌作用机制。方法采用活性追踪分离的方法,运用硅胶柱层析、Sephadex LH-20凝胶柱层析和半制备HPLC等手段,对采自中国南海的柳珊瑚Echinogorgia rebekka中分离获得的共附生链格孢霉属真菌Alternaria sp.(WZL003)的发酵产物进行分离和纯化,利用NMR、MS等波谱方法,并与文献对照,确定化合物的结构;以海洋病原菌和污损菌鳗弧菌Vibrio anguillarum为对象研究化合物的抑菌作用机制。结果从该菌发酵液的乙酸乙酯提取物中,分离获得1个对V.anguillarum具有较强抑菌活性的蒽醌类化合物macrosporin。结论初步的抑菌作用机制研究发现,该化合物能破坏鳗弧菌的细胞壁和细胞膜,导致细胞通透性增加,胞内大量内容物外泄,最终导致菌体死亡,从而起到抑菌作用。本研究首次报道了macrosporin对鳗弧菌的抑菌作用及其作用机制。  相似文献   
116.
美国食品药品监督管理局(FDA)于2020年6月发布了“医院获得性细菌性肺炎和呼吸机相关性细菌性肺炎:供企业用治疗药物开发指导原则”。该指导原则阐述了治疗这类疾病的抗菌药物临床研究的一般原则和具体试验设计的建议。介绍该指导原则的主要内容,期待对中国“医院获得性细菌性肺炎/呼吸机相关细菌性肺炎抗菌药物临床试验技术指导原则(征求意见稿)”的定稿和促进这类药物的研究有帮助。  相似文献   
117.
Oxazines have brought much synthetic interest due to their extensive biological activities. These are the important category of heterocycles, which may be formally derived from benzene and its reduction products by convenient substitution of carbon (and hydrogen) atoms by nitrogen and oxygen. In the last few decades, oxazine derivatives have documented as worthy synthetic intermediates and also blessed with notable sedative, analgesic, anticonvulsant, antipyretic, antimicrobial, antitubercular, antimalarial, antioxidant, and anticancer activities. Nowadays, it is important to develop new classes of compounds with more effective mechanisms due to drug resistance activity in which the ability of drug to effectively treat disease can be reduced. The aim of the article is to collect and make a more generalized review on the synthesis of oxazine derivatives and their pharmaceutical and biological activities. We hope this review will provide ample references for the researchers concerned with azines in generally and oxazines in particular.  相似文献   
118.
目的:分析医院抗菌药物临床使用现状,为临床抗菌药物合理使用提供参考。方法:抽取医院2016年—2018年抗菌药物临床使用资料,分析其销售金额、用药频度(DDDs)、日均费用(DDC)、构成比和各年度是否增长。结果:2016年—2018年3年间医院西药销售总金额分别为33594.71万元、32142.13万元和29692.84万元,其中抗菌药物金额分别为6385.39万元、6111.56万元和5777.92万元,抗菌药物销售金额占西药总金额平均为19.15%;抗菌药物金额年均下降4.87%;抗菌药物金额列第1、2位的分别为第3、2代头孢菌素类;DDDs列第1、2位主要为大环内酯类和第3代头孢菌素类;非限制和限制使用级抗菌药物销售金额构成比分别为17.14%和70.03%,其DDDs构成比分别为59.44%和38.44%;特殊使用级抗菌药物销售金额和DDDs下降明显;抗菌药物口服和注射剂型的销售金额约占20%和80%,其DDDs分别为69%和31%;单品种销售金额列前3位为头孢替安、头孢硫脒、哌拉西林钠-他唑巴坦钠和头孢哌酮-舒巴坦钠;单品种DDDs列前3位的为克拉霉素、头孢克肟、头孢羟氨苄。结论:医院抗菌药物临床使用较为规范、合理,但抗菌药物规范化管理任重道远,应持之以恒、持续改进。  相似文献   
119.
The widespread use of antibiotics has contributed to a huge increase in the number of resistant bacteria. New classes of drugs are therefore being developed of which defensins are a potential source. Defensins are a group of antimicrobial peptides found in different living organisms, involved in the first line of defense in their innate immune response against pathogens. This review summarizes the results of studies of this family of human antimicrobial peptides (AMPs). There is a special emphasis on describing the entire group and individual peptides, history of their discovery, their functions and expression sites. The results of the recent studies on the use of the biologically active peptides in human medicine are also presented. The pharmaceutical potential of human defensins cannot be ignored, especially considering their strong antimicrobial activity and properties such as low molecular weight, reduced immunogenicity, broad activity spectrum and resistance to proteolysis, but there are still many challenges and questions regarding the possibilities of their practical application.  相似文献   
120.
The ability of T cells to activate antimicrobial pathways in infected macrophages is essential to host defence against many intracellular pathogens. Here, we compared the ability of two T‐cell‐mediated mechanisms to trigger antimicrobial responses against Mycobacterium tuberculosis in humans, CD40 activation and the release of interferon‐γ (IFN‐γ). Given that IFN‐γ activates a vitamin D‐dependent antimicrobial response, we focused on induction of the key components of this pathway. We show that activation of human monocytes via CD40 ligand (CD40L) and IFN‐γ, alone, and in combination, induces the CYP27b1‐hydroxylase, responsible for the conversion of 25‐hydroxyvitamin D (25D) to the bioactive 1,25‐dihydroxyvitamin D (1,25D), and the vitamin D receptor (VDR). The activation of the vitamin D pathway by CD40L and IFN‐γ results in up‐regulated expression of the antimicrobial peptides, cathelicidin and DEFB4, as well as induction of autophagy. Finally, activation of monocytes via CD40L and IFN‐γ results in an antimicrobial activity against intracellular M. tuberculosis. Our data suggest that at least two parallel T‐cell‐mediated mechanisms, CD40L and IFN‐γ, activate the vitamin D‐dependent antimicrobial pathway and trigger antimicrobial activity against intracellular M. tuberculosis, thereby contributing to human host defence against intracellular infection.  相似文献   
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