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   275篇
  国内免费   4篇
  完全免费   23篇
  药学   302篇
  2020年   1篇
  2019年   13篇
  2018年   30篇
  2017年   23篇
  2016年   4篇
  2015年   4篇
  2014年   10篇
  2013年   17篇
  2012年   18篇
  2011年   23篇
  2010年   25篇
  2009年   30篇
  2008年   19篇
  2007年   8篇
  2006年   9篇
  2005年   6篇
  2004年   6篇
  2003年   7篇
  2002年   9篇
  2001年   5篇
  1998年   3篇
  1997年   3篇
  1996年   5篇
  1995年   4篇
  1993年   7篇
  1992年   4篇
  1991年   2篇
  1990年   1篇
  1989年   1篇
  1988年   3篇
  1987年   1篇
  1986年   1篇
排序方式: 共有302条查询结果,搜索用时 35 毫秒
1.
Hydrogel nanoparticles in drug delivery   总被引:5,自引:0,他引:5  
Hydrogel nanoparticles have gained considerable attention in recent years as one of the most promising nanoparticulate drug delivery systems owing to their unique potentials via combining the characteristics of a hydrogel system (e.g., hydrophilicity and extremely high water content) with a nanoparticle (e.g., very small size). Several polymeric hydrogel nanoparticulate systems have been prepared and characterized in recent years, based on both natural and synthetic polymers, each with its own advantages and drawbacks. Among the natural polymers, chitosan and alginate have been studied extensively for preparation of hydrogel nanoparticles and from synthetic group, hydrogel nanoparticles based on poly (vinyl alcohol), poly (ethylene oxide), poly (ethyleneimine), poly (vinyl pyrrolidone), and poly-N-isopropylacrylamide have been reported with different characteristics and features with respect to drug delivery. Regardless of the type of polymer used, the release mechanism of the loaded agent from hydrogel nanoparticles is complex, while resulting from three main vectors, i.e., drug diffusion, hydrogel matrix swelling, and chemical reactivity of the drug/matrix. Several crosslinking methods have been used in the way to form the hydrogel matix structures, which can be classified in two major groups of chemically- and physically-induced crosslinking.  相似文献
2.
The supramolecular structures formed between cyclodextrins (CDs) and polymers have inspired interesting developments of novel supramolecular biomaterials. This review will update the recent progress in studies on supramolecular structures based on CDs and block copolymers, followed by the design and synthesis of CD-based supramolecular hydrogels and biodegradable polyrotaxanes for potential controlled drug delivery, and CD-containing cationic polymers and cationic polyrotaxanes for gene delivery. Supramolecular hydrogels based on the self-assembly of the inclusion complexes between CDs with biodegradable block copolymers could be used as promising injectable drug delivery systems for sustained controlled release of macromolecular drugs. Biodegradable polyrotaxanes with drug-conjugated CDs threaded on a polymer chain with degradable end-caps could be interesting supramolecular prodrugs for controlled and targeting delivery of drugs. CD-containing cationic polymers as gene carriers showed reduced cytotoxicity than non-CD-containing polymer counterparts. More importantly, the polyplexes of CD-containing cationic polymers with DNA could be pegylated through a supramolecular process using inclusion complexation between the CD moieties and a modified PEO. Finally, new cationic polyrotaxanes composed of multiple oligoethylenimine-grafted CDs threaded and end-capped on a block copolymer chain were designed and synthesized as a new class of polymeric gene delivery vectors, where the chain-interlocked cationic cyclic units formed an integrated supramolecular entity to function as a macromolecular gene vector. The development of the supramolecular biomaterials through inclusion complexation has opened up a new approach for designing novel drug and gene delivery systems, which may have many advantages over the systems based on the conventional polymeric materials.  相似文献
3.
羧甲基壳聚糖/聚乙烯醇水凝胶处方及制备工艺优化   总被引:4,自引:1,他引:3  
目的:优选羧甲基壳聚糖(CMCS)/聚乙烯醇(PVA)水凝胶的处方及制备工艺;初步考察载药水凝胶的体外释药规律。方法:合成不同取代度的CMCS;以羧甲基壳聚糖的取代度,2%戊二醛的用量及温度为考察因素,各取三水平,以水凝胶在pH1.2溶液中的膨胀率为考察指标进行L9(3^4)正交实验;并以甲硝唑为模型药物,对水凝胶的体外释药做初步考察。结果:取代度为0.38的CMCS,在0.2mL的2%戊二醛做交联剂于室温下交联,有最大膨胀率(24.54±1.04)(n=3);以最佳条件制备的甲硝唑水凝胶于0.1mol·L^-1盐酸溶液中在8h内累积释药率达(89.95±1.05)%(n=3)。结论:CMCS/PVA水凝胶最佳处方在pH1.2时具有理想的膨胀率,可做为胃部释药载体进一步研究。  相似文献
4.
Chitosan-based hydrogels for controlled, localized drug delivery   总被引:2,自引:0,他引:2  
Hydrogels are high-water content materials prepared from cross-linked polymers that are able to provide sustained, local delivery of a variety of therapeutic agents. Use of the natural polymer, chitosan, as the scaffold material in hydrogels has been highly pursued thanks to the polymer's biocompatibility, low toxicity, and biodegradability. The advanced development of chitosan hydrogels has led to new drug delivery systems that release their payloads under varying environmental stimuli. In addition, thermosensitive hydrogel variants have been developed to form a chitosan hydrogel in situ, precluding the need for surgical implantation. The development of these intelligent drug delivery devices requires a foundation in the chemical and physical characteristics of chitosan-based hydrogels, as well as the therapeutics to be delivered. In this review, we investigate the newest developments in chitosan hydrogel preparation and define the design parameters in the development of physically and chemically cross-linked hydrogels.  相似文献
5.
温敏型姜黄素鼻用原位凝胶增强脑靶向性   总被引:1,自引:0,他引:1  
目的:制备温度敏感型的姜黄素鼻用凝胶制剂,以提高姜黄素的脑部生物利用度。方法:通过粘度实验进行原位凝胶制剂的处方筛选,以胶凝时间、胶凝温度等为指标,优化处方;采用透析袋法考察原位凝胶的体外释放:以大鼠为模型,考察姜黄素原位凝胶的脑靶向性及脑内分布.并与其静脉注射剂相比较。结果:姜黄素原位凝胶剂优化处方具有最短的胶凝时间,可以长时间粘附在鼻腔粘膜上:释放行为属于Fickian扩散机制;姜黄素脑内分布试验表明,原位凝胶在大脑、小脑、海马、嗅球中的药物靶向效率(DTE)分别为静脉给药的1.82、2.05、2.07、1.51倍,说明原位凝胶给药显著增强了姜黄素的脑靶向性。结论:制备的姜黄素原位凝胶剂具有温度敏感的特点.并显著提高了姜黄素的脑靶向性。  相似文献
6.
尼莫地平水凝胶贴剂的制备及其体外透皮性能研究   总被引:1,自引:0,他引:1  
王凤娟  金涌  王毓洁  周轶凡 《中国药房》2010,(29):2714-2717
目的:制备尼莫地平水凝胶贴剂,并考察不同因素对尼莫地平体外透皮性的影响。方法:以羧甲基纤维素钠为骨架材料制备尼莫地平水凝胶贴剂,采用透皮扩散试验仪,以离体小鼠皮肤为屏障进行体外透皮实验,高效液相色谱法测定药物浓度,并计算药物累积透皮量Q和透皮速率常数Js。以Q值和Js值为指标,筛选投药量、透皮促进剂的种类(薄荷醇、氮酮、油酸)和用量。结果:最佳投药量为4 mg·cm-2,不同透皮促进剂对尼莫地平均有透皮促进作用,其中以5%油酸作用最显著。以5%油酸为透皮促进剂制备的样品的透皮吸收行为符合零级动力学过程,Js值为28.10μg·cm-2·h-1,12 h单位面积Q值为342.58μg·cm-2。结论:尼莫地平水凝胶贴剂可以开发为经皮给药制剂。  相似文献
7.
聚氧乙烯骨架缓释片的处方及体外释药机制研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的以聚氧乙烯(PEO)为亲水凝胶骨架制备缓释片剂,并考察其体外释药机制。方法基于两种规格PEO的用量比与释药速率之间的关系,优化缓释片处方。通过考察片剂的体外释放度和溶蚀比探讨其释药机制,并对不同溶解度药物的体外释放行为进行比较。结果缓释片体外释药速率与PEO用量比呈线性关系,所得优化处方在12h内以接近恒速释药,其体外释药与溶蚀过程基本同步,且在所考察用量范围内不同溶解度药物的体外释放度相近。结论PEO制成的亲水凝胶骨架片缓释性能良好,其体外释药是药物扩散和骨架溶蚀协同作用的结果。  相似文献
8.
大黄素温敏凝胶治疗慢性牙周炎临床观察   总被引:1,自引:1,他引:0  
赵兵  赵权  彭伟  穆玉 《中国基层医药》2010,17(16):2165-2167
目的 观察大黄素温敏凝胶治疗慢性牙周炎的临床疗效及安全性. 方法 选取40例慢性牙周炎患者采用同一口腔内病情相同牙齿的自身对照研究设计,分成观察组40个牙和对照组40个牙,观察两组治疗前后各阶段各项临床指标的变化情况. 结果 观察组和对照组在治疗前各项临床指标差异均无统计学意义(均P>0.05);在治疗后第6周时,两组PLI、SBI、PD、AL、MD与治疗前比较均有显著改善(t=39.06、62.76、20.50、8.05、158.32、31.45、46.53、8.43、8.08、8.03,均P<0.01),而观察组较对照组改善更为明显(t=31.50、27.91、3.92、7.38、20.09,均P<0.01);在治疗后第12周时,两组PLI均有所反弹,但与治疗后6周时差异无统计学意义(P>0.05),观察组与对照组之间差异有统计学意义(t=23.39,P<0.01);治疗后第12周时观察组SBI、PD、AL、MD较治疗后第6周时有明显改善(t=3.50、21.18、9.93、9.05,均P<0.01),与对照组差异均有统计学意义(t=30.69、5.76、13.41、25.60,均P<0.01). 结论 大黄素温敏凝胶可以有效控制慢性牙周炎引起的各种临床症状.  相似文献
9.
经乳晕切口取出聚丙烯酰胺水凝胶80例临床观察   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:探讨聚丙烯酰胺水凝胶注射隆乳后的手术取出方法。方法:对80例隆重乳者分别采用乳晕下半缘切口进行聚丙烯酰胺水凝胶取出治疗。结果:72例感效果满意,8例术后乳房形态欠佳。结论:对大多数聚丙烯酰胺水凝胶隆乳采用乳晕下半缘切口进行取出手术能得到满意效果,乳房瘢痕不明显,并发症少,外形较佳。  相似文献
10.
Advances in medical treatments of a wide variety of pathophysiological conditions require the development of better therapeutic agents, as well as a combination of the required therapeutic agents with device-integrated biomaterials that can serve as sensors and carriers. Combination of micro- and nano-fabricated systems with intelligent biomaterials that have the ability to sense and respond is a promising avenue for the development of better diagnostic and therapeutic medical systems. Micro- and nano-electromechanical systems (MEMs and NEMs) are now becoming a family of potentially powerful new technologies for drug delivery, diagnostic tools, and tissue engineering. Improvements in micro- and nano-fabrication technologies have enhanced the ability to create better performing therapeutic systems for numerous pathophysiological applications. More importantly, MEMS- and NEMS-based tissue regeneration scaffolds, biosensors, and drug delivery devices provide new opportunities to mimic the natural intelligence and response of biological systems.  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