全文获取类型
收费全文 | 51255篇 |
免费 | 4572篇 |
国内免费 | 1533篇 |
专业分类
耳鼻咽喉 | 133篇 |
儿科学 | 700篇 |
妇产科学 | 1027篇 |
基础医学 | 7454篇 |
口腔科学 | 1369篇 |
临床医学 | 6248篇 |
内科学 | 6395篇 |
皮肤病学 | 419篇 |
神经病学 | 6830篇 |
特种医学 | 1131篇 |
外科学 | 4918篇 |
综合类 | 6098篇 |
现状与发展 | 2篇 |
一般理论 | 1篇 |
预防医学 | 4325篇 |
眼科学 | 529篇 |
药学 | 6584篇 |
29篇 | |
中国医学 | 2045篇 |
肿瘤学 | 1123篇 |
出版年
2024年 | 74篇 |
2023年 | 905篇 |
2022年 | 1225篇 |
2021年 | 2239篇 |
2020年 | 2353篇 |
2019年 | 1964篇 |
2018年 | 1891篇 |
2017年 | 2138篇 |
2016年 | 2267篇 |
2015年 | 2207篇 |
2014年 | 3682篇 |
2013年 | 4750篇 |
2012年 | 3245篇 |
2011年 | 3587篇 |
2010年 | 2825篇 |
2009年 | 2801篇 |
2008年 | 2858篇 |
2007年 | 2438篇 |
2006年 | 2179篇 |
2005年 | 1648篇 |
2004年 | 1504篇 |
2003年 | 1325篇 |
2002年 | 1009篇 |
2001年 | 882篇 |
2000年 | 716篇 |
1999年 | 548篇 |
1998年 | 483篇 |
1997年 | 420篇 |
1996年 | 355篇 |
1995年 | 296篇 |
1994年 | 278篇 |
1993年 | 215篇 |
1992年 | 240篇 |
1991年 | 207篇 |
1990年 | 208篇 |
1989年 | 184篇 |
1988年 | 154篇 |
1987年 | 122篇 |
1986年 | 122篇 |
1985年 | 154篇 |
1984年 | 130篇 |
1983年 | 77篇 |
1982年 | 87篇 |
1981年 | 70篇 |
1980年 | 65篇 |
1979年 | 63篇 |
1978年 | 46篇 |
1977年 | 32篇 |
1976年 | 30篇 |
1973年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
22.
《Saudi Pharmaceutical Journal》2022,30(11):1665-1671
5-fluorouracil (5FU) is widely used to treat colorectal cancer (CC) and its main mechanisms of anticancer action are through generation of ROS which often result in inflammation. Here, we test the effect of Lycopene against 5FU in Caco2 cell line. Caco2 cells were exposed to 3 µg/ml of 5FU alone or with 60, 90, 120 µg/ml of lycopene. This was followed by assessment of cytotoxicity, oxidative stress, and gene expression of inflammatory genes. Our findings showed that Lycopene and 5FU co-exposure induced dose-dependent cytotoxic effect without compromising the membrane integrity based on the LDH assay. Lycopene also significantly enhanced 5FU-induced SOD activity and GSH level compared to control for all mixture concentrations (p < 0.01). Lycopene alone and combination with 5FU-induced expression of IL-1β, TNF-α, and IL-6. Furthermore, IFN-γ expression was significantly enhanced by only mixture of lycopene (90 µg/ml) and 5FU (p < 0.05). In conclusion, Lycopene supplementation with 5FU therapy resulted in improvement in antioxidant parameters such as catalase and GSH levels giving the cell capacity to cope with 5FU-mediated oxidative stress. Lycopene also enhanced IFN-γ expression in the presence of 5FU, which may activate antitumor effects further enhancing the cancer killing effect of 5FU. 相似文献
23.
《Gait & posture》2022
BackgroundTraditional running shoes with heel-to-toe drops is thought to be a contributor to increased patellofemoral joint stress, which is proposed as a mechanism of patellofemoral pain.Research questionIs there an increase in patellofemoral joint stress when running in shoes with drops compared to running in shoes without a drop?MethodsLower limbs kinematics and ground reaction force were collected from eighteen healthy runners during over-ground running in shoes with 15 mm, 10 mm, 5 mm drops, and without a drop. Patellofemoral joint force and stress were calculated from the kinematic and kinetic data using a biomechanical model of the patellofemoral joint.ResultsThe peak patellofemoral joint stress was increased by more than 15% when running in shoes with 15 mm and 10 mm drops compared to running in shoes without a drop (p = 0.003, p = 0.001). The knee flexion angle was significantly increased when running in shoes with 15 mm, 10 mm and 5 mm drops (p = 0.014, p = 0.003, p = 0.002), the knee extension moment (p = 0.009, p = 0.002) and patellofemoral joint force (p = 0.003, p = 0.001) were increased when running in shoes with 15 mm and 10 mm drops, compared to running in shoes without a drop.SignificanceCompared to running in shoes without a drop, running in shoes with drops > 5 mm increase the peak patellofemoral joint stress significantly, which is mainly due to the increased knee extension moment. 相似文献
24.
25.
26.
27.
28.
创伤后应激障碍(PTSD)是指突发性、威胁性或灾难性生活事件导致个体延迟出现和长期持续存在的精神障碍,其临床表现以再度体验创伤为特征,并伴有情绪的易激惹和回避行为。PTSD的发生不仅伴随着行为学指标异常,机制研究表明还表现出神经生物学指标异常。PTSD的发生机制研究多集中在神经内分泌系统、中枢神经系统和免疫系统等方面,主要表现为应激激素、促炎细胞因子、神经递质、神经保护因子的水平异常。中药因其具有多靶点、多成分和多途径的特点,在治疗PTSD方面表现出了许多优势。当前研究表明,多种中药能够改善PTSD模型中动物行为异常、逆转神经生物学指标。其中很多中药复方已经应用于临床并且具有很好的疗效,因此中药治疗PTSD具有广阔的应用前景。但是,尚未有PTSD的专属治疗药物,且尚未完全厘清PTSD的机制。故本文对当前中药治疗PTSD的研究进行综述,并且从治疗的中药种类、作用机制、动物模型等角度,重点阐述PTSD的发生与治疗进展,以期为PTSD的治疗提供参考。 相似文献
29.
Suppression of Rotenone-Treated Human Breast Cancer Stem Cell Survival Using Survivin Inhibitor YM155 is Associated to Oxidative Stress Modulation 下载免费PDF全文
Resda A SyahraniElvira YunitaSeptelia I Wanandi 《Asian Pacific journal of cancer prevention》2020,21(9):2631-2637
Background: Despite recent progress in molecular-targeted therapies, breast cancer remains the primary leading cause of cancer related death among women worldwide. Breast cancer stem cells (BCSCs) are believed to be responsible for therapy resistance and cancer recurrence. We recently demonstrated that human BCSCs (CD24-/CD44+) could survive better than their counterpart non-BCSCs (CD24-/CD44-) when treated with rotenone, possibly due to lower levels of reactive oxygen species (ROS) production, high expression of antioxidant manganese superoxide dismutase (MnSOD), and anti-apoptotic survivin. The aim of this study was to verify the role of survivin on human BCSCs survival under oxidative stress modulation by suppressing its expression using YM155, a survivin inhibitor. Methods: Human BCSCs (ALDH+ cells) were treated with YM155 for 24 h prior to treatment with rotenone for a further 6 h. We determined intracellular superoxide levels were determined using dihydroethidium assay, survivin and MnSOD expression using qRT-PCR, survivin protein level using ELISA, as well as cell viability using trypan blue exclusion and acridine orange/ethidium bromide apoptosis assay. Results: Suppression of survivin expression using YM155 could reduce the survival of rotenone-treated BCSCs, which may be associated with oxidative stress modulation, as shown by increased ROS levels and decreased MnSOD expression. We confirm that survivin is responsible for maintaining BCSCs survival under oxidative stress modulation. Furthermore, YM155 could modulate oxidative stress in BCSCs by reducing MnSOD expression and increasing ROS levels. Conclusion: YM155 treatment could be used to overcome BCSCs resistance to oxidative stress-based anticancer therapies. 相似文献
30.