全文获取类型
收费全文 | 1601958篇 |
免费 | 131795篇 |
国内免费 | 2585篇 |
专业分类
耳鼻咽喉 | 21666篇 |
儿科学 | 53004篇 |
妇产科学 | 46226篇 |
基础医学 | 227806篇 |
口腔科学 | 47202篇 |
临床医学 | 140933篇 |
内科学 | 314997篇 |
皮肤病学 | 34096篇 |
神经病学 | 130147篇 |
特种医学 | 64740篇 |
外国民族医学 | 474篇 |
外科学 | 243856篇 |
综合类 | 39728篇 |
现状与发展 | 3篇 |
一般理论 | 544篇 |
预防医学 | 122888篇 |
眼科学 | 36470篇 |
药学 | 121277篇 |
3篇 | |
中国医学 | 2974篇 |
肿瘤学 | 87304篇 |
出版年
2018年 | 14774篇 |
2016年 | 12905篇 |
2015年 | 15031篇 |
2014年 | 20652篇 |
2013年 | 31358篇 |
2012年 | 42566篇 |
2011年 | 44758篇 |
2010年 | 26337篇 |
2009年 | 25308篇 |
2008年 | 43005篇 |
2007年 | 45247篇 |
2006年 | 46062篇 |
2005年 | 44679篇 |
2004年 | 44097篇 |
2003年 | 42184篇 |
2002年 | 41305篇 |
2001年 | 75689篇 |
2000年 | 78339篇 |
1999年 | 66398篇 |
1998年 | 17744篇 |
1997年 | 16343篇 |
1996年 | 16319篇 |
1995年 | 16029篇 |
1994年 | 15075篇 |
1993年 | 14221篇 |
1992年 | 55434篇 |
1991年 | 53777篇 |
1990年 | 52565篇 |
1989年 | 50834篇 |
1988年 | 47224篇 |
1987年 | 46560篇 |
1986年 | 44288篇 |
1985年 | 42848篇 |
1984年 | 32034篇 |
1983年 | 27567篇 |
1982年 | 16144篇 |
1981年 | 14438篇 |
1980年 | 13564篇 |
1979年 | 30462篇 |
1978年 | 21064篇 |
1977年 | 17766篇 |
1976年 | 16695篇 |
1975年 | 17574篇 |
1974年 | 21487篇 |
1973年 | 20672篇 |
1972年 | 18854篇 |
1971年 | 17770篇 |
1970年 | 16289篇 |
1969年 | 15270篇 |
1968年 | 13949篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Randomised clinical study: the effects of oral taurine 6g/day vs placebo on portal hypertension 下载免费PDF全文
92.
Cost‐Effectiveness Analysis of Sacubitril/Valsartan for the Treatment of Heart Failure with Reduced Ejection Fraction in the United States 下载免费PDF全文
93.
Joseph J. Knapik Krista G. Austin Emily K. Farina Harris R. Lieberman 《Journal of the Academy of Nutrition and Dietetics》2018,118(8):1370-1388
Background
Dietary supplement (DS) use is prevalent among the US Armed Forces personnel, but representative cross-service comparisons and characteristics of personnel using DSs are limited.Objective
Examine DS use and characteristics associated with use in a representative sample of US Armed Forces personnel (Army, Navy, Air Force, Marine Corps, and Coast Guard) using data from the 2011 Department of Defense Survey of Health-Related Behaviors.Design and participants
A stratified random sample of service members (SMs) was contacted and asked to complete a questionnaire assessing personal characteristics and DS use.Results
Overall, 69% of the 39,877 SMs reported using DSs ≥1 time per week. The most commonly used DSs were multivitamin or multiminerals (50%), antioxidants (34%), individual vitamins or minerals (33%), bodybuilding supplements (27%), fish oils (26%), herbals (16%), and weight-loss supplements (16%). Multiple logistic regression indicated overall DS use was higher among women, those with higher educational levels, Marine Corps SMs, officers, those with higher body mass index, those engaged in greater physical activity and weight training, and people in weight control programs. DS use was lower when peer groups or leadership discouraged substance abuse.Conclusions
DS use was considerably higher in the US Armed Forces compared with civilian populations, although many demographic and lifestyle factors associated with use were similar. Some categories of DSs extensively used by SMs such as bodybuilding supplements have been associated with adverse events. Discouraging substance abuse through peer groups and leadership actions may reduce use of unnecessary or dangerous DSs. 相似文献94.
95.
Linfeng Wu Wu Chen Feng Li Brian R. Morrow Franklin Garcia-Godoy Liang Hong 《Journal of pharmaceutical sciences》2018,107(12):3134-3142
It is important to address the periodontitis-associated bacteria in the residual subgingival plaque after scaling and root planing to successfully treat periodontitis. In this study, we explored the possibility of exploiting the ion pairing/complexation of minocycline, Ca2+, and sulfate/sulfonate-bearing biopolymers to develop an intrapocket delivery system of minocycline as an adjunct to scaling and root planing. Minocycline-calcium-dextran sulfate complex microparticles were synthesized from minocycline, CaCl2, and dextran sulfate. They were characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. An in vitro release study was conducted to evaluate the release kinetics of minocycline from these microparticles. Agar disk diffusion assays and biofilm-grown bacteria assays were used to assess antibacterial capability. High loading efficiency (96.98% ± 0.12%) and high loading content (44.69% ± 0.03%) for minocycline were observed for these complex microparticles. Mino-Ca-DS microparticles achieved sustained release of minocycline for at least 9 days at pH 7.4 and 18 days at pH 6.4 in phosphate-buffered saline, respectively. They also demonstrated potent antimicrobial effects against Streptococcus mutans and Aggregatibacter actinomycetemcomitans in agar disk diffusion and biofilm assays. These results suggested that the ion pairing/complexation of minocycline, Ca2+, and sulfonate/sulfate-bearing biopolymers can be exploited to develop complex microparticles as local delivery systems for periodontitis treatment. 相似文献
96.
Verônica M. Couto Maria J. Prieto Daniela E. Igartúa Daniela A. Feas Lígia N.M. Ribeiro Camila M.G. Silva Simone R. Castro Viviane A. Guilherme Darlene D. Dantzger Daisy Machado Silvia del V. Alonso Eneida de Paula 《Journal of pharmaceutical sciences》2018,107(9):2411-2419
Administration of local anesthetics is one of the most effective pain control techniques for postoperative analgesia. However, anesthetic agents easily diffuse into the injection site, limiting the time of anesthesia. One approach to prolong analgesia is to entrap local anesthetic agents in nanostructured carriers (e.g., liposomes). Here, we report that using an ammonium sulphate gradient was the best strategy to improve the encapsulation (62.6%) of dibucaine (DBC) into liposomes. Light scattering and nanotracking analyses were used to characterize vesicle properties, such as, size, polydispersity, zeta potentials, and number. In vitro kinetic experiments revealed the sustained release of DBC (50% in 7 h) from the liposomes. In addition, in vitro (3T3 cells in culture) and in vivo (zebrafish) toxicity assays revealed that ionic-gradient liposomes were able to reduce DBC cyto/cardiotoxicity and morphological changes in zebrafish larvae. Moreover, the anesthesia time attained after infiltrative administration in mice was longer with encapsulated DBC (27 h) than that with free DBC (11 h), at 320 μM (0.012%), confirming it as a promising long-acting liposome formulation for parenteral drug administration of DBC. 相似文献
97.
98.
99.
Letter: predicting azathioprine‐associated pancreatitis in IBD—phenotype or genotype? Authors' reply 下载免费PDF全文
100.