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   1384篇
  免费   136篇
  国内免费   138篇
  1658篇
  2024年   2篇
  2023年   24篇
  2022年   49篇
  2021年   76篇
  2020年   57篇
  2019年   71篇
  2018年   68篇
  2017年   64篇
  2016年   81篇
  2015年   108篇
  2014年   108篇
  2013年   120篇
  2012年   121篇
  2011年   111篇
  2010年   73篇
  2009年   63篇
  2008年   72篇
  2007年   56篇
  2006年   58篇
  2005年   30篇
  2004年   35篇
  2003年   29篇
  2002年   30篇
  2001年   19篇
  2000年   15篇
  1999年   27篇
  1998年   5篇
  1997年   4篇
  1995年   3篇
  1994年   8篇
  1993年   5篇
  1992年   13篇
  1991年   8篇
  1990年   3篇
  1989年   4篇
  1988年   5篇
  1987年   7篇
  1985年   4篇
  1984年   3篇
  1983年   2篇
  1981年   2篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1975年   2篇
  1974年   3篇
  1973年   2篇
  1971年   1篇
  1969年   1篇
  1968年   2篇
排序方式: 共有1658条查询结果,搜索用时 15 毫秒
31.
32.

In this work, an overview of the biosimilars market, pipeline and industry targets is discussed. Biosimilars typically have a shorter timeline for approval (8 years) compared to 12 years for innovator drugs and the development cost can be 10–20% of the innovator drug. The biosimilar pipeline is reviewed as well as the quality management system (QMS) that is needed to generate traceable, trackable data sets. One difference between developing a biosimilar compared to an originator is that a broader analytical foundation is required for biosimilars and advances made in developing analytical similarity to characterize these products are discussed. An example is presented on the decisions and considerations explored in the development of a biosimilar and includes identification of the best process parameters and methods based on cost, time, and titer. Finally factors to consider in the manufacture of a biosimilar and approaches used to achieve the target-directed development of a biosimilar are discussed.

  相似文献   
33.
Hydrothermal vents are considered as one of the most extremely harsh environments on the Earth. In this study, the complete mitogenomes of hydrothermal vent squat lobsters, Munidopsis lauensis and M. verrilli, were determined through Illumina sequencing and compared with other available mitogenomes of anomurans. The mitogenomes of M. lauensis (17,483 bp) and M. verrilli (17,636 bp) are the largest among all Anomura mitogenomes, while the A+T contents of M. lauensis (62.40%) and M. verrilli (63.99%) are the lowest. The mitogenomes of M. lauensis and M. verrilli display novel gene arrangements, which might be the result of three tandem duplication–random loss (tdrl) events from the ancestral pancrustacean pattern. The mitochondrial gene orders of M. lauensis and M. verrilli shared the most similarities with S. crosnieri. The phylogenetic analyses based on both gene order data and nucleotide sequences (PCGs and rRNAs) revealed that the two species were closely related to Shinkaia crosnieri. Positive selection analysis revealed that eighteen residues in seven genes (atp8, Cytb, nad3, nad4, nad4l, nad5, and nad6) of the hydrothermal vent anomurans were positively selected sites.  相似文献   
34.
A weak ion exchange monolithic column prepared by modifying the GMA-MAA-EDMA (glycidyl methacrylate-methacrylic acid-ethylene glycol dimethacrylate) monoliths with ethylenediamine was applied to remove matrix compounds in biological fluid. Using this monolithic column, on-line clean-up and screening of oxacillin and cloxacillin in human urine and plasma samples had been investigated. Chromatography was performed by reversed-phase HPLC on a C(18) column with ultraviolet detection at 225 nm. Results showed that the ion exchange monolithic column could be used for deproteinization and retaining oxacillin and cloxacillin in human urine and plasma, which provided a simple and fast method for assaying drugs in human urine and plasma.  相似文献   
35.
36.
Biomedical application of nanotechnology is a rapidly developing area that raises new prospect in the improvement of diagnosis and treatment of human diseases. The ability to incorporate drugs or genes into a functionalized nanoparticle demonstrates a new era in pharmacotherapy for delivering drugs or genes selectively to tissues or cells. It is envisioned that the transfer of nanoengineering capability into disease therapy will provide constant and concentrated drug delivery to targeted tissues, minimizing systemic side effects and toxicity. We have in this article highlighted the recent state of the art in nanomedicine, focusing particularly on the achievement of nanotechnology in nanoscale drug and gene delivery in vitro and in vivo. In addition, a specific emphasis has been placed on the use of nanotechnology to improve controlled drug release and sustainable drug delivery in solid tumors and on new drug therapies for age-related neurodegenerative disorders.  相似文献   
37.
38.
Wang  Xuhui  Wang  Hong  Zhang  Tao  He  Meng  Liang  Hong  Wang  Hao  Xu  Lunshan  Chen  Sha  Xu  Minhui 《Neurochemical research》2019,44(7):1690-1702

Trigeminal neuralgia (TN) is a type of chronic neuropathic pain that is caused by peripheral nerve lesions that result from various conditions, including the compression of vessels, tumors and viral infections. MicroRNAs (miRs) are increasingly recognized as potential regulators of neuropathic pain. Previous evidence has demonstrated that miR-195 is involved in neuropathic pain, but the mechanism remains unclear. To investigate the pathophysiological role of miR-195 and Shh signaling in TN, persistent facial pain was induced by infraorbital nerve chronic constriction injury (CCI-IoN), and facial pain responses were evaluated by Von Frey hairs. qPCR and Western blotting were used to determine the relative expression of miR-195 and Patched1, the major receptor of the Sonic Hedgehog (Shh) signaling pathway, in the caudal brain stem at distinct time points after CCI-IoN. Here, we found that the expression of miR-195 was increased in a rat model of CCI-IoN. In contrast, the expression of Patched1 decreased significantly. Luciferase assays confirmed the binding of miR-195 to Patched1. In addition, the overexpression of miR-195 by an intracerebroventricular (i.c.v) administration of LV-miR-195 aggravated facial pain development, and this was reversed by upregulating the expression of Patched1. These results suggest that miR-195 is involved in the development of TN by targeting Patched1 in the Shh signaling pathway, thus regulating extracellular glutamate.

  相似文献   
39.
Understanding the mechanism of water infiltration through nanopores is essential for wide applications ranging from membrane separation to gene therapy. In this paper, the molecular dynamics simulation method is used to investigate the pressure-assisted water transport process through graphene nanopores. Various factors including the hydrophobicity of nanopore surface, nanopore dimension, temperature as well as external electric field that affect water in permeation into graphene nanopores are discussed. It is found that classic Laplace-Young equation fails and the relationship between pressure and diameter (D) does not follow the 1/D dependence as the characteristic dimension of a nanopore is sufficiently small (smaller than 1?nm). The critical pressure significantly depends on both the pore length and electric field as D is smaller than 5?nm. Besides, enhancing temperature and electric field intensity are obviously beneficial for water infiltration through those nanopores with a diameter smaller than 5?nm.  相似文献   
40.
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