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   9633篇
  免费   639篇
  国内免费   182篇
耳鼻咽喉   197篇
儿科学   121篇
妇产科学   171篇
基础医学   1666篇
口腔科学   117篇
临床医学   724篇
内科学   2145篇
皮肤病学   293篇
神经病学   688篇
特种医学   571篇
外科学   1259篇
综合类   50篇
一般理论   3篇
预防医学   343篇
眼科学   395篇
药学   806篇
中国医学   110篇
肿瘤学   795篇
  2024年   4篇
  2023年   66篇
  2022年   242篇
  2021年   367篇
  2020年   173篇
  2019年   257篇
  2018年   345篇
  2017年   237篇
  2016年   443篇
  2015年   559篇
  2014年   573篇
  2013年   709篇
  2012年   992篇
  2011年   922篇
  2010年   538篇
  2009年   457篇
  2008年   555篇
  2007年   578篇
  2006年   431篇
  2005年   436篇
  2004年   361篇
  2003年   285篇
  2002年   239篇
  2001年   104篇
  2000年   100篇
  1999年   72篇
  1998年   43篇
  1997年   22篇
  1996年   19篇
  1995年   18篇
  1994年   15篇
  1993年   22篇
  1992年   34篇
  1991年   31篇
  1990年   23篇
  1989年   26篇
  1988年   16篇
  1987年   22篇
  1986年   15篇
  1985年   15篇
  1984年   5篇
  1983年   9篇
  1982年   13篇
  1981年   5篇
  1980年   7篇
  1979年   14篇
  1978年   10篇
  1977年   6篇
  1976年   8篇
  1975年   4篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
For the long‐term efficacy of dry eye disease treatment, relieving underlying inflammation is necessary. Imatinib mesylate is a novel ophthalmic formulation of imatinib mesylate, which is expected to alleviate inflammation by inhibiting the discoidin domain receptor 1 activity. This study aims to evaluate the safety and pharmacokinetics of imatinib mesylate in healthy subjects. A randomized, double‐blind, placebo‐controlled study was conducted. In a single ascending dose, 16 subjects received a single eye drop of imatinib mesylate 0.1%, 0.3%, or matching placebo. In the multiple ascending dose (MAD), subjects received multiple eye drops of imatinib mesylate 0.1%, 0.3%, or matching placebo once daily for 7 days. Safety and tolerability were assessed by ophthalmic examination, including the visual analog scale (VAS) to monitor the burning sensation in the eyes. A total of four treatment‐emergent adverse events (TEAEs) occurred during the study. All TEAEs were mildly severe with no serious cases. VAS results in the 0.1% MAD group exhibited highest score of two points, whereas it was less than one point in others. Insignificant difference between the imatinib mesylate and placebo groups in the VAS results was seen. After a single dose administration of imatinib mesylate 0.1%, all plasma concentrations were below the lower limit of quantification. The peak plasma concentrations of imatinib were less than 0.54 µg/L in all groups. In conclusion, a single and multiple topical ophthalmic administration of imatinib mesylate was well‐tolerated in healthy subjects. Because there was minimal systemic exposure to imatinib, the adverse effect in the body seems to be insignificant.  相似文献   
72.
Yoga has been known to have stimulatory or inhibitory effects on the metabolic parameters and to be uncomplicated therapy for obesity. The purpose of the present study was to test the effect of an 8-week of yoga-asana training on body composition, lipid profile, and insulin resistance (IR) in obese adolescent boys. Twenty volunteers with body mass index (BMI) greater than the 95th percentile were randomly assigned to yoga (age 14.7±0.5 years, n=10) and control groups (age 14.6±1.0 years, n=10). The yoga group performed exercises three times per week at 40~60% of heart-rate reserve (HRR) for 8 weeks. IR was determined with the homeostasis model assessment of insulin resistance (HOMA-IR). After yoga training, body weight, BMI, fat mass (FM), and body fat % (BF %) were significantly decreased, and fat-free mass and basal metabolic rate were significantly increased than baseline values. FM and BF % were significantly improved in the yoga group compared with the control group (p<0.05). Total cholesterol (TC) was significantly decreased in the yoga group (p<0.01). HDL-cholesterol was decreased in both groups (p<0.05). No significant changes were observed between or within groups for triglycerides, LDL-cholesterol, glucose, insulin, and HOMA-IR. Our findings show that an 8-week of yoga training improves body composition and TC levels in obese adolescent boys, suggesting that yoga training may be effective in controlling some metabolic syndrome factors in obese adolescent boys.  相似文献   
73.
Type 1 diabetes (T1D) is caused by dysregulation of the immune system in the pancreatic islets, which eventually leads to insulin-producing pancreatic β-cell death and destabilization of glucose homeostasis. One of the major characteristics of T1D pathogenesis is the production of inflammatory mediators by macrophages that result in destruction or damage of pancreatic β-cells. In this study the inflammatory microenvironment of T1D was simulated with RAW264.7 cells and MIN6 cells, acting as macrophages and pancreatic β-cells respectably. In this setting, peroxiredoxin-1, an anti-oxidant enzyme was knocked down to observe its functions in the pathogenesis of T1D. RAW264.7 cells were primed with lipopolysaccharide and co-cultured with MIN6 cells while PRX-1 was knocked down in one or both cell types. Our results suggest that hindrance of PRX-1 activity or the deficiency of this enzyme in inflammatory conditions negatively affects pancreatic β-cell survival. The observed decrease in viability of MIN6 cells seems to be caused by nitric oxide production. Additionally, it seems that PRX-1 affects previously reported protective activity of IL-6 in pancreatic β cells as well. These results signify new, undiscovered roles for PRX-1 in inflammatory conditions and may contribute toward our understanding of autoimmunity.  相似文献   
74.
We investigated the effects of β-glucan purified from Paenibacillus polymyxa JB115 on the viability and proliferation of splenocytes. Splenocytes play a critical role in host immunity. MTT assays and trypan blue exclusion tests revealed that β-glucan significantly promoted the viability and proliferation of splenocytes over a range of concentrations. However, there was no specific subset change. β-glucan protected splenocytes from cytokine withdrawal-induced spontaneous cell death. For further mechanistic studies, ELISA assay revealed that β-glucan enhanced the expression of anti-apoptotic molecules and interleukin 7 (IL-7), a cytokine critical for lymphocyte survival. We also investigated the IL-2 dependency of β-glucan-treated splenocytes to determine if treated cells could still undergo clonal expansion. In flow cytometric analysis, β-glucan induced increased levels of the activation marker CD25 on the surface of splenocytes and β-glucan-treated splenocytes showed higher proliferation rates in response to IL-2 treatment. This study demonstrates that β-glucan can enhance the survival of splenocytes and provides valuable information to broaden the use of β-glucan in research fields.  相似文献   
75.
Activated T cells express inhibitory receptors such as CTLA-4 that can downregulate immune responses. Blockade of or genetic deficiency in CTLA-4 can result in autoimmunity. Therefore, strategies to increase the inhibitory function of CTLA-4 may be attractive in settings of undesirable T cell responses such as autoimmunity or transplant rejection. We have tested the hypothesis that transgenic constitutive expression of CTLA-4 can further attenuate immune responses when compared with normal inducible expression. Our results indicate that transgenic expression of CTLA-4 in mouse T cells (CTLA-4-Tg T cells) results in reduced cell cycle progression and increased apoptosis of TCR-stimulated T cells. CTLA-4-Tg T cells display reduced T cell proliferation in an in vivo model of graft versus host disease (GVHD). These results further our understanding of how CTLA-4 can be manipulated to inhibit immune responses and may help development of new therapeutic strategies for clinical settings of autoimmunity and transplantation.  相似文献   
76.
TNF-?? is an endogenous signaling protein which controls physiological activities and participates in immune response. It is known to interact with TNF receptors (TNFR), of which have two kinds leading to totally different effects. Binding of TNF-?? to TNFR1 can induce either cell proliferation or cell death, i.e., necroptosis, depending on the kinds of protein to which it binds during the signaling cascade. On the contrary, binding of TNF-?? to TNFR2 induces only cell death process. TNF-?? can also cause antiviral effect by inducing interferon, and can inhibit tumor growth. Moreover, TNF-?? helps action of immune cells and it leads to increasement of tumor cell lysis. TNF-?? also makes tumor vessels more permeable and induces coagulation and thrombosis in the tumor vessels, which ultimately contribute to antitumor effect. However, TNF-?? also has several toxic effects, which include the change in redox status of antioxidant factors, induction of excess inflammation response, and action as pro-inflammatory cytokine of itself. These toxicities need to be considered when developing TNF-?? as an anticancer agent. In this review, pharmaceutical approaches to optimize and utilize its antitumor activity of TNF-?? as well as to decrease its adverse effect are discussed.  相似文献   
77.
78.
79.
80.
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