首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1715篇
  免费   176篇
  国内免费   80篇
耳鼻咽喉   7篇
儿科学   14篇
妇产科学   21篇
基础医学   121篇
口腔科学   18篇
临床医学   192篇
内科学   89篇
皮肤病学   48篇
神经病学   32篇
特种医学   26篇
外科学   84篇
综合类   255篇
预防医学   165篇
眼科学   29篇
药学   639篇
  1篇
中国医学   194篇
肿瘤学   36篇
  2024年   5篇
  2023年   38篇
  2022年   61篇
  2021年   71篇
  2020年   50篇
  2019年   46篇
  2018年   54篇
  2017年   47篇
  2016年   64篇
  2015年   63篇
  2014年   154篇
  2013年   146篇
  2012年   128篇
  2011年   151篇
  2010年   87篇
  2009年   79篇
  2008年   79篇
  2007年   90篇
  2006年   86篇
  2005年   59篇
  2004年   50篇
  2003年   50篇
  2002年   37篇
  2001年   23篇
  2000年   26篇
  1999年   19篇
  1998年   15篇
  1997年   14篇
  1996年   10篇
  1995年   20篇
  1994年   10篇
  1993年   11篇
  1992年   18篇
  1991年   10篇
  1990年   8篇
  1989年   10篇
  1988年   7篇
  1987年   7篇
  1986年   9篇
  1985年   12篇
  1984年   8篇
  1983年   5篇
  1982年   3篇
  1981年   5篇
  1980年   5篇
  1979年   3篇
  1978年   6篇
  1977年   5篇
  1976年   3篇
  1975年   3篇
排序方式: 共有1971条查询结果,搜索用时 531 毫秒
1.
中药复方冬虫夏草透皮乳膏的研制及质量控制   总被引:3,自引:0,他引:3  
目的:探讨复方冬虫夏草透皮乳膏的制备及其质量控制。方法:选用适宜乳膏基质,将冬虫夏草、昆明山海棠浓缩液与透皮促进剂制成O/W型乳膏,建立质量控制方法。结果:本制剂质量稳定,保湿性良好,能显著延长猪同种植皮存活期。结论:复方冬虫夏草乳膏剂的制备工艺可行,性质稳定。质量控制方法简单、可靠。  相似文献   
2.
色甘酸钠混悬气雾剂与茶碱缓释胶囊治疗中度哮喘的比较   总被引:1,自引:1,他引:0  
84例中度哮喘病人分成2组。色甘酸钠组(男性23例,女性20例,年龄26±s8a)吸入色甘酸钠混悬气雾剂10.5mg,tid。茶碱缓释胶囊组(男性22例,女性19例,年龄27±8a)口服0.25g。bid。2组均连续观察3mo。结果:色甘酸钠在减轻病人慢性症状、改善肺功能和降低气道高反应性等方面优于茶碱缓释胶囊,(P<0.01)。而后药仅可缓解近期症状。  相似文献   
3.
目的探讨不同方法治疗压疮的临床效果。方法将65例患者计Ⅱ~Ⅲ度溃疡84处按基本条件相当原则随机分成A、B、C三组,A组21例28处,伤口采用清创冲洗后,给予康惠尔水胶体敷料;B组23例30处,伤口采用湿润烧伤膏;C组21例26处,清创冲洗后,给予自制凡士林油纱敷料外敷溃疡面处。结果B组愈合率最高,且平均显效时间和愈合时间均较A、C两组明显缩短,且A、B组明显高于C组。结论采用清创冲洗后用湿润烧伤膏是治疗压疮较好的方法之一。  相似文献   
4.
Objectives/Hypothesis: Numerous mechanical animal models for the creation of otitis media with effusion (OME) have been described since the 1920s. However, there are many problems associated with these models, including high infection rates, unreliability, and high resolution rates. The aim of the current study was to create a suitable mechanical animal model that would produce a sterile and long-lasting effusion. Study Design: A new technique using an external surgical approach on specific pathogen–free rats is described. Method: The eustachian tubes of 56 rats were obstructed in the mid portion along the skull base with gutta percha. Results: All animals developed an effusion within 1 week of the procedure. The resolution rate was 8%, with 80% maintaining sterile effusions for up to 1 year. Conclusions: This new procedure for an OME model has proved consistently reliable in creating a persistent and long-lasting effusion. It has a low infection rate and should benefit future studies on the prolonged effects of OME on the tympanic membrane and middle ear.  相似文献   
5.
During intracellular recordings in rodent brainstem slice preparations, dorsal cochlear nucleus (DCN) pyramidal cells (PCs) exhibit characteristic discharge patterns to depolarizing current injection that depend on the membrane potential from which the responses are evoked. When depolarized from hyperpolarized potentials, PCs can respond with a short-latency action potential followed by a long silent interval (pauser) or a train of action potentials with a long latency (buildup). During the silent intervals in a pauser or a buildup response, the membrane potential slowly depolarizes towards spike threshold, often exhibiting distinct voltage oscillations of 1–2 mV before the first spike. The subthreshold voltage oscillations were investigated using whole cell recordings from DCN PCs in rat pup (P10–14) brainstem slices. The oscillations were unaffected by excitatory and inhibitory neurotransmitter antagonists, and were not temporally locked to the onset of the depolarization. The oscillations typically became larger as spike threshold was approached, and had a characteristic frequency between 40 and 100 Hz. In the presence of tetrodotoxin (TTX, 500 nM), the oscillations were significantly suppressed, and could not be evoked at any voltage below or above spike threshold. The oscillations were not blocked by phenytoin or Cd2+, but they were affected by prior activity in the neuron for approximately 1 s. We conclude that voltage-gated Na+ channels are required to generate membrane oscillations during the buildup phase. We suggest that the subthreshold oscillations play a role in controlling spike timing in PCs when the membrane potential slowly approaches, or hovers near, spike threshold.  相似文献   
6.
The IgG subclasses of immunoglobulin for intravenous injection (IVIg) were investigated after various different types of treatment. The level of IgG2 was relatively low in preparations treated with pepsin, but by changing the clone producing anti-IgG2 antibody, the level approached that of normal human serum. Though undetectable in sulfonated immunoglobulin preparations, IgG3 was detected after reoxidation. When determining the IgG subclasses of IVIg, it must be kept in mind that the apparent value may subsequently become lower due to the depressed reaction of the antibody.  相似文献   
7.
Cell preparations of ventral mesencephalon obtained from 8-, 14-, and 16-17-day rat embryos were stereotactically transplanted to homologous rats with 6-hydroxydopamine-induced hemiparkinsonism. Automated analysis of apomorphine-induced motor asymmetry for 3 months after neurotransplantation revealed higher efficacy of cell preparations from 8- and lower from 16-17-day-old embryos. These data correlated with histomorphological findigs, in particular, with the size of grafts, glial reaction, and the number of dopaminergic neurons in the grafts.  相似文献   
8.
Summary Samples of 96 polyvalent and virus-specific immunoglobulin batches commercially available in West-Germany were tested by enzyme-linked immunoassay and immunoblot for the presence of anti-HTLV-III antibodies. 37% of the polyvalent and 87% of the virus-specific batches were positive. It was concluded that these preparations are still safe and because of their reportedly low titer neutralizing antibodies possibly beneficial in certain cases, such as newborns of HTLV-III positive mothers or after accidental exposure to infectious material in clinics or laboratories.Abbreviations AIDS acquired immunodeficiency syndrome - ARC AIDS-related complex - CMV cytomegalovirus - ELISA enzyme-linked immuno adsorbent assay - HTLV-III human T-cell lymphotropic virus, type III  相似文献   
9.
Synthetic dyes were extracted from syrups, oral suspensions, tablets, gelatin capsules, suppositories and granules by ion-pair formation with tri-n-octylamine (TnOA) and back-extracted with perchlorate ions. Identification was performed by TLC on cellulose layers and by reversed phase ion-pair HPLC.  相似文献   
10.
The medicinally important quaternary ammonium salts benzyldimethyltetradecylammonium chloride (BDTA), cetylpyridinium chloride and benzethonium chloride, all afford, under fast atom bombardment (FAB) mass spectrometric conditions, abundant and persistent [M---Cl]+ species usefully amenable to quantitative analysis with the aid of thioglycerol as a liquid FAB matrix. The use of BDTA as an internal standard allowed a direct, precise and accurate determination of cetylpyridinium and benzethonium chlorides, either as pure samples or in dosage forms, in the concentration range 0.05–2 mg/ml.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号