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91.
目的观察萝卜硫素(SFN)体外抗氧化和抑菌活性。方法试剂盒检测SFN总抗氧化能力(TAC)、抑制超氧阴离子(O2-)活力;水杨酸比色法和邻苯三酚自氧化法检测羟自由基(OH-)与超氧阴离子(O2-)清除能力;滤纸片法检测SFN的抑菌作用,连续二倍稀释法测定其最低抑菌浓度(MIC)、最低杀菌浓度(MBC)和对大肠杆菌和金色葡球菌生长的抑制。结果 SFN在体外模拟系统中总抗氧化活性和抑制抑制O2-生成活力较高,但对OH-和O2-的直接清除率较低,低于30%。抑菌结果表明SFN对大肠杆菌、金色葡萄球菌、绿脓杆菌、枯草杆菌、表皮葡萄球菌5种受试菌均有较强的抑制作用,MIC为0.78~6.25μg/ml之间。结论 SFN具有较好的抗氧化活性和较强的抑菌效果。  相似文献   
92.
Infection is one of the most important obstacles in the wound‐healing process. Conventional methods used for the treatment of wound infections have their own limitations and hence, are difficult to control. If infection is not addressed well in time, it will further increase morbidity and cost of treatment. An attempt was made to develop a simple and effective treatment modality by using citric acid as the sole antimicrobial agent to control bacterial infections of traumatic wounds. A total of 259 cases of traumatic wounds infected with a variety of bacteria were investigated for culture and susceptibility, and susceptibility to citric acid. Citric acid ointment (3%) was applied to traumatic wounds to determine its efficacy in their treatment of traumatic wounds. In a culture and susceptibility study, a total of 369 aerobic bacteria and 7 fungi were isolated, with Staphylococcus aureus (30·31%) being the most common isolate and ciprofloxacin (61·43%) being the most effective agent. All the isolates were found to be inhibited by citric acid in in vitro studies (minimum inhibitory concentration – 500–2500 µg/ml). Citric acid ointment was found effective in controlling infections. Out of 259 cases, 244 (around 95%) were healed completely in 5–25 applications of 3% citric acid. As citric acid has antibacterial activity and wound‐healing property; hence it is the best alternative for the treatment of traumatic wounds. Besides these properties, citric acid has no adverse effects and it is a good dressing agent.  相似文献   
93.
目的 通过对1例难治性泌尿系合并血流感染患者实施抗感染药学监护,同时加强临床药师在外科感染药物治疗方面的经验。方法 临床药师对患者在ICU治疗期间实施全程药学监护,直到患者病情平稳转回原科室。监护内容主要包括评估目前抗感染用药分析,与医师制定抗感染治疗方案,密切关注病情,评估疗效及不良反应并调整方案等。结果 经过积极治疗后,患者的病情得到改善。结论 临床药师参与药学实践对于帮助医师提高药物治疗的疗效具有重要意义。  相似文献   
94.
We present a simple and facile approach for preparing antibacterial magnetic nanoparticles, which were modified with quaternarized N-halamine based cationic polymer (CPQN). The CPQN functionalized magnetic nanoparticles (MNPs-CPQN) were characterized by X-ray photoelectron spectra, Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, and thermogravimetric analysis. Antibacterial properties were investigated with Gram positive bacteria S. aureus and Gram negative bacteria E. coli. Antibacterial assessment showed that the MNPs-CPQN could eliminate nearly 100% of S. aureus and 99.9% of E. coli (107-8 CFU/mg nanoparticles) in 5 min, while the bactericide rate of quaternized N-halamine precursor based cationic polymer coated magnetic nanoparticles (MNPs-CPQNP) were 99.6 and 95.2%, respectively. The prepared nanoparticles exhibited a good response to an external magnetic field and had a saturation magnetization of 36.6 emu g?1. On the basis of their excellent antibacterial properties and magnetic responsiveness, the MNPs-CPQN would be a promising antibacterial material for water disinfection.  相似文献   
95.
The lack of availability of novel antibiotic agents and the rise of resistance to existing therapies has led clinicians to utilise combination therapy to adequately treat bacterial infections. Here we examined how chelators may impact the in vitro activity of tigecycline (TIG) against Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae. Minimum inhibitory concentrations (MICs) were determined by broth dilution with and without various combinations of chelators (EDTA and other tetracyclines) and metal ions (i.e. calcium, magnesium). Trimethoprim (TMP) was used as a non-chelating control. Addition of metal ions led to increases in MICs, whilst addition of EDTA led to decreases in MICs. The chelating effects of EDTA were reversed by addition of magnesium and most profoundly calcium. Similar effects of EDTA and calcium were observed for tetracycline (TET) and TMP. When other tetracyclines (TET, oxytetracycline (OXY) and chlortetracycline (CHL)) were used as chelators at concentrations below their MICs, TIG MICs decreased for P. aeruginosa but not for E. coli. Some decreases in TIG MICs were observed for K. pneumoniae when TET and CHL were added. A dose-dependent decrease in TIG MIC was observed for TET and was reversed by the addition of calcium. The presence of effects of EDTA and calcium on TMP MICs indicates that mechanisms outside of TIG chelation likely play a role in enhanced activity. Full characterisation of an unexpected interaction such as TIG–TET with different microorganisms could provide valuable insights into the underlying mechanisms and design of physiologically viable chelators as candidates for future combinations regimens.  相似文献   
96.
目的 抗菌药磷酸特地唑胺的工艺研究。方法 QbD理念指导工艺研究,以中间体A和焦磷酸四苄酯为原料合成磷酸特地唑胺。结果 以58%的总收率实现了磷酸特地唑胺的制备,HPLC纯度为99.2%。 结论 新开发的工艺反应条件温和,有效地避免了水解杂质、二聚体杂质的产生,保证了磷酸特地唑胺的产品质量。  相似文献   
97.
摘 要 目的:探讨恩施地区药品不良反应发生特点及土家族与汉族发生抗菌药物不良反应(ADR)的差异。方法:选取2012年1月~2017年7月恩施地区上报的ADR报告,从患者一般情况、ADR严重程度及发生时间、β 内酰胺类ADR、给药途径及ADR转归等方面,比较土家族及汉族患者发生的ADR的差异。结果:土家族与汉族患者发生的ADR,在β 内酰胺类尤其是头孢菌素类药物所致ADR分布、口服与静脉滴注用药分布,以及ADR转归情况等方面的差异有统计学意义(P<0.01)。两者发生ADR严重程度无差异(P﹥0.05)。结论:ADR的发生存在种族差异,少数民族地区在使用抗菌药物及给药途径方面应关注民族差异,减少ADR发生。  相似文献   
98.
摘 要本文综述了氨溴索药动学、药效学特点以及氨溴索与抗菌药物相互作用的文献,对氨溴索与抗菌药物的使用顺序进行了分析探讨。氨溴索与抗菌药物联合使用可提高抗菌药物在肺泡灌洗液(BALF)中的浓度;氨溴索对病原菌生物膜(BF)具有抑制和破坏作用,且氨溴索对BF的作用具有剂量依赖性,大剂量氨溴索安全性良好。临床上先应用氨溴索,再使用抗菌药物,可有利于提高抗菌药物在肺组织中的浓度,有利于抗菌药物进入病原菌BF内部,从而增强抗菌效果。针对氨溴索药品说明书,建议进一步修改和完善:①在药品说明书相关项下明确氨溴索与抗菌药物的用药顺序;②在说明书中增加氨溴索在不同适应症下的用药剂量;③明确大剂量氨溴索临床使用的安全性和有效性。  相似文献   
99.
Bone infections are difficult to treat and can lead to severe tissue destruction. Acute bone infections are usually caused by Staphylococcus aureus. Osteoclasts, which belong to the monocyte/macrophage lineage, are the key cells in bone infections. They are not well equipped for killing bacteria and may serve as a reservoir for bacterial pathogens. Silver has been known for centuries for its bactericidal activity. Here, we investigated the bactericidal effects of nano-silver particles in bacteria infected human osteoclasts. We found that nano-silver in per se non-toxic concentration enhanced the bactericidal activity in osteoclasts against intracellular Methicillin-resistant, virulent Staphylococcus aureus. The reduced bacterial survival in nano-silver pretreated cells correlated with increased reactive oxygen responses towards the invading pathogens. Overall, these results indicate that nano-silver compounds should be considered as an effective treatment and prevention option for bacterial bone and orthopedic implant infections.  相似文献   
100.
ZnO and Zn acetate nanoparticles were embedded in polycaprolactone coaxial-fibers and uniaxial-fibers matrices to develop potential antibacterial nanocomposite wound dressings (mats). Morphology, composition, wettability, crystallinity and fiber structure of mats were characterized. Antibacterial properties of mats were tested against E. coli and S. aureus by turbidity and MTT assays. The effect of UVA illumination (prior to bacteria inoculation) on mats’ antibacterial activity was also studied. Results showed that a coaxial-fibers design maintained nanoparticles distributed in the outer-shell of fibers and, in general, enhanced the antibacterial effect of the mats, in comparison to conventional uniaxial-fibers mats. Results indicated that mats simultaneously inhibited planktonic and biofilm bacterial growth by, probably, two main antibacterial mechanisms; 1) release of Zn2+ ions (mainly from Zn acetate nanoparticles) and 2) photocatalytic oxidative processes exerted by ZnO nanoparticles. Antibacterial properties of mats were significantly improved by coaxial-fibers design and exposure to UVA-light prior to bacteria inoculation.  相似文献   
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