全文获取类型
收费全文 | 8908篇 |
免费 | 556篇 |
国内免费 | 91篇 |
专业分类
耳鼻咽喉 | 114篇 |
儿科学 | 110篇 |
妇产科学 | 168篇 |
基础医学 | 773篇 |
口腔科学 | 395篇 |
临床医学 | 761篇 |
内科学 | 1048篇 |
皮肤病学 | 96篇 |
神经病学 | 263篇 |
特种医学 | 490篇 |
外科学 | 2021篇 |
综合类 | 935篇 |
一般理论 | 1篇 |
预防医学 | 677篇 |
眼科学 | 68篇 |
药学 | 1072篇 |
12篇 | |
中国医学 | 335篇 |
肿瘤学 | 216篇 |
出版年
2024年 | 18篇 |
2023年 | 211篇 |
2022年 | 387篇 |
2021年 | 579篇 |
2020年 | 474篇 |
2019年 | 410篇 |
2018年 | 397篇 |
2017年 | 359篇 |
2016年 | 336篇 |
2015年 | 330篇 |
2014年 | 640篇 |
2013年 | 755篇 |
2012年 | 451篇 |
2011年 | 536篇 |
2010年 | 408篇 |
2009年 | 382篇 |
2008年 | 369篇 |
2007年 | 363篇 |
2006年 | 317篇 |
2005年 | 254篇 |
2004年 | 219篇 |
2003年 | 175篇 |
2002年 | 135篇 |
2001年 | 120篇 |
2000年 | 93篇 |
1999年 | 111篇 |
1998年 | 80篇 |
1997年 | 65篇 |
1996年 | 65篇 |
1995年 | 62篇 |
1994年 | 48篇 |
1993年 | 37篇 |
1992年 | 24篇 |
1991年 | 32篇 |
1990年 | 32篇 |
1989年 | 20篇 |
1988年 | 27篇 |
1987年 | 25篇 |
1986年 | 22篇 |
1985年 | 28篇 |
1984年 | 27篇 |
1983年 | 14篇 |
1982年 | 28篇 |
1981年 | 10篇 |
1980年 | 12篇 |
1979年 | 18篇 |
1978年 | 8篇 |
1977年 | 10篇 |
1976年 | 9篇 |
1974年 | 6篇 |
排序方式: 共有9555条查询结果,搜索用时 31 毫秒
101.
目的 利用几种常规的炮制方法分析草乌中乌头碱、次乌头碱和新乌头碱的减毒情况。方法 将大小形状不同的草乌样品分别经过水煮法、蒸法及烘烤法进行不同时长炮制,采用超高效液相色谱串联质谱进行含量测定分析,外标法定量。结果 3种乌头碱在0.20~100.0μg/L浓度范围内均具有良好的线性关系,相关系数均大于0.9997。草乌不同形状减毒效果为粉末>片状>完整个头,不同炮制方法减毒效果为水煮>蒸>烘烤,烘烤炮制对草乌样品未有良好减毒效果。浓度为1.0μg/mL的乌头碱、新乌头碱和次乌头碱标准品分别经过0.5h、1.5h和1.5h水煮炮制可达到100%完全降解,但其他炮制样品的减毒效果根据不同的炮制方法显现出较大差异性。结论 3种乌头碱经过足够时长的水煮及蒸法炮制均可达到显著的减毒效果,烘烤法对草乌减毒作用较小,民间食用草乌的安全性应引起高度重视。 相似文献
102.
表皮生长因子(EGF)10μg/L作用于人子宫颈癌(Hela)细胞,24h、48h未见细胞数量改变,第5d时可观察到细胞由原来的呈椭圆形克隆样生长变为有树突样胞质突出的长梭状较均匀地分布生长:EGF作用下,Hela细胞噻唑蓝还原呈剂量依赖性增加.提示EGF不能促进Hela细胞增殖,但可引起细胞形态改变及线粒体脱氢酶活性增高,这可能与EGF促分化作用有关. 相似文献
103.
电视胸腔镜解剖学肺叶切除20例 总被引:2,自引:0,他引:2
目的 探讨电视胸腔镜(VATS)辅助小切口解剖学肺叶切除术的手术式和手术指征,尤其对肺癌的手术。方法 应用VATXS辅助小切口中小学肺叶切除手术20例,手术通过胸前外侧7cm左右辅助小切口,VATS专用器械和常规开胸器械联合使用。20例肺叶切除共用缝合切割器(ENDOPATH)钉仑44只,肺癌病人通过小切口均作了肺门及纵隔淋巴结摘除。3例术中因胸膜腔粘连肺裂不完整和门血管粘连出血处理困难,将辅助小 相似文献
104.
目的总结五年颌骨骨折治疗体会,探讨有关问题.方法选用1995年3月至2000年3月治疗的颌骨骨折465例,男348例、女117例.根据就诊时间早晚、致伤原因、骨折部位及分类,治疗方法选择进行总结.结果治疗有效率98.92%,行紧急气管切开术45例,抗体克12例,手术切开复位骨间固定284例,手法或牵引复位外固定181例,术后感染骨延迟愈合8例(1.7%)合并颅脑损伤死亡5例(1.08%).结论①排除颅脑及内脏损伤,保证无窒息、休克发生,通过临床表现确诊骨折类型.②要使骨折片尽早复位,应用坚固内固定技术保证骨块不再移位,恢复伤前咬合关系,软组织要严密缝合.③正确地运用正颌外科技术,使陈旧性骨折达到三维立体方向复位. 相似文献
105.
手性修饰的硼氢化钠对前手性酮的不对称还原 总被引:3,自引:0,他引:3
研究了以N-苄基-(3S,4S)-3,4-二羟基四氢吡咯修饰的硼氢化钠对前手性酮的不对称还原反应,合成了五个光学活性醇,同时研究了添加路易斯酸对还原反应光学产率的影响。 相似文献
106.
107.
《Genetics in medicine》2023,25(2):100329
PurposeMost patients with Gaucher disease have progressive and often disabling skeletal manifestations. We examined the long-term effect of eliglustat treatment on bone outcomes in clinical trials in adults with Gaucher disease type 1.MethodsData from 4 completed phase 2 and 3 trials were evaluated in treatment-naïve patients or patients switching to eliglustat from enzyme replacement therapy (ERT).ResultsOverall, 319 of 393 (81%) eliglustat-treated patients remained in their trials until completion or commercial eliglustat became available. Mean eliglustat treatment duration ranged from 3.3 to 6.5 years. In treatment-naïve patients and ERT-switch patients, frequency and severity of bone pain decreased during eliglustat treatment. Mean lumbar spine T-scores shifted from abnormal to normal in treatment-naïve patients and remained in the healthy reference range or improved modestly in ERT-switch patients. Mean total bone marrow burden score shifted from marked-to-severe to moderate in treatment-naïve patients and remained moderate in ERT-switch patients. MIP-1β (marker of active bone disease) was elevated at baseline and decreased to the healthy reference range in treatment-naïve patients and remained in the healthy reference range among ERT-switch patients.ConclusionThese findings confirm the long-term efficacy of eliglustat on skeletal complications of Gaucher disease in treatment-naïve and ERT-switch patients. 相似文献
108.
Hellawell K 《Drug and alcohol review》1995,14(3):317-322
Illicit drugs have become a major global problem in recent decades following considerable recent political change, including the collapse of communism and the formation of international super-states to increase trade. Despite increasing collaboration between law enforcement authorities in different countries, illicit drug problems appear likely to increase in the future because of the vast profits available, continuing (and increasing) demand and more permissive attitudes concerning drugs among young people. While rejecting legalization or decriminalization, the search for more effective responses by law enforcement authorities and the community generally must be stepped up. Police services continue to play an important role restricting the availability of illicit drugs but increasing emphasis needs to be given to reducing demand, including more available and more effective preventive drug education in schools. Police also need to work with harm reduction approaches devised to reduce the negative consequences of drug use for those who continue to use illicit drugs. New measures proposed in Britain are outlined. These stress the importance of a multi-sectoral approach operating at both national and local levels with the objective of reducing drug-related crime, reducing the acceptability and availability of illicit drugs and reducing the harmful consequences of illicit drug use. Harm reduction requires a commitment for close collaboration between police and drug treatment services to maximize the effectiveness of needle-exchange schemes and other harm reduction approaches. Cautioning, now commonly used in Britain for selected minor drug offences, has a number of benefits including reducing criminal justice costs. Greater emphasis must be placed on diversion schemes involving close links between police and drug treatment services. Future progress requires firm commitments to providing adequate and effective drug treatment services, conducting research to develop and evaluate more effective diversion schemes, improving collaboration between sectors and effective leadership. In addition to the major costs of illicit drug use to the community, the huge cost to individuals must remain a major focus driving the search for more effective responses to the problems resulting from illicit drugs. 相似文献
109.
Harm reduction in the developing world 总被引:1,自引:0,他引:1
Samarasinghe D 《Drug and alcohol review》1995,14(3):305-309
This paper examines harm reduction from the perspective of poor countries. In considering which elements of the broad approach are suitable for adaptation and adoption by poor countries, there is a need to examine critically the arguments put forth in support of it and which, if any, of these are supported by evidence. There are also significant indirect influences that the approach is likely to have on how drug use is understood and interpreted by wider society. The likely impact of these on areas other than simply services directed to drug users needs to be assessed. There are some features regarding harm caused by alcohol and other drug use that are specific to poor countries. Most important among these is that levels of use which are not deemed to be harmful in rich societies cause grave harm through diverting meagre resources away from survival needs in the poor world. Alcohol, as well as other drugs, tends in deprived settings to cause dependence and other problems much earlier in people's drinking careers and at much lower levels of consumption than in rich countries. 相似文献
110.
Defining harm reduction 总被引:1,自引:0,他引:1
Single E 《Drug and alcohol review》1995,14(3):287-290
Harm reduction attempts to reduce the adverse consequences of drug use among persons who continue to use drugs. It developed in response to the excesses of a “zero tolerance approach”. Harm reduction emphasizes practical rather than idealized goals. It has been expanded from illicit drugs to legal drugs and is grounded in the evolving public health and advocacy movements. Harm reduction has proved to be effective and it has gained increasing official acceptance; for example, it is now the basis of Canada's Drug Strategy. However, the concept is still poorly defined, as virtually any drug policy or programme, even abstinence-oriented programmes, attempt to reduce drug-related harm. The principle feature of harm reduction is the acceptance of the fact that some drug users cannot be expected to cease their drug use at the present time. Harm reduction is neutral about the long term goals of intervention while according a high priority to short-term realizable goals. Harm reduction should be neutral about legalization. The essence of the concept is to ameliorate adverse consequences of drug use while, at least in the short term, drug use continues. 相似文献