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   21235篇
  免费   898篇
  国内免费   84篇
耳鼻咽喉   287篇
儿科学   563篇
妇产科学   562篇
基础医学   3924篇
口腔科学   549篇
临床医学   1414篇
内科学   2885篇
皮肤病学   636篇
神经病学   1865篇
特种医学   1850篇
外科学   2750篇
综合类   193篇
一般理论   2篇
预防医学   1543篇
眼科学   307篇
药学   1930篇
中国医学   144篇
肿瘤学   813篇
  2023年   122篇
  2022年   171篇
  2021年   385篇
  2020年   251篇
  2019年   352篇
  2018年   559篇
  2017年   422篇
  2016年   567篇
  2015年   514篇
  2014年   714篇
  2013年   1121篇
  2012年   1577篇
  2011年   1890篇
  2010年   1016篇
  2009年   525篇
  2008年   1193篇
  2007年   1359篇
  2006年   1307篇
  2005年   1079篇
  2004年   1003篇
  2003年   1012篇
  2002年   828篇
  2001年   540篇
  2000年   700篇
  1999年   440篇
  1998年   171篇
  1997年   149篇
  1996年   94篇
  1995年   113篇
  1994年   81篇
  1993年   53篇
  1992年   86篇
  1991年   73篇
  1990年   85篇
  1989年   80篇
  1988年   80篇
  1987年   52篇
  1986年   49篇
  1985年   73篇
  1984年   73篇
  1983年   72篇
  1982年   67篇
  1981年   64篇
  1980年   56篇
  1979年   64篇
  1978年   70篇
  1977年   52篇
  1976年   57篇
  1975年   63篇
  1974年   46篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
The circadian rhythm in humans is determined by the central clock located in the hypothalamus’s suprachiasmatic nucleus, and it synchronizes the peripheral clocks in other tissues. Circadian clock genes and clock-controlled genes exist in almost all cell types. They have an essential role in many physiological processes, including lipid metabolism in the liver, regulation of the immune system, and the severity of infections. In addition, circadian rhythm genes can stimulate the immune response of host cells to virus infection. Hepatitis B virus (HBV) infection is the leading cause of liver disease and liver cancer globally. HBV infection depends on the host cell, and hepatocyte circadian rhythm genes are associated with HBV replication, survival, and spread. The core circadian rhythm proteins, REV-ERB and brain and muscle ARNTL-like protein 1, have a crucial role in HBV replication in hepatocytes. In addition to influencing the virus’s life cycle, the circadian rhythm also affects the pharmacokinetics and efficacy of antiviral vaccines. Therefore, it is vital to apply antiviral therapy at the appropriate time of day to reduce toxicity and improve the effectiveness of antiviral treatment. For these reasons, understanding the role of the circadian rhythm in the regulation of HBV infection and host responses to the virus provides us with a new perspective of the interplay of the circadian rhythm and anti-HBV therapy. Therefore, this review emphasizes the importance of the circadian rhythm in HBV infection and the optimization of antiviral treatment based on the circadian rhythm-dependent immune response.  相似文献   
2.
3.
4.
Clinical Oral Investigations - The aim of this study was the analysis of WNT10A variants in seven families of probands with various forms of tooth agenesis and self-reported family history of...  相似文献   
5.
6.
7.
8.
BACKGROUND Degree of portal hypertension(PH) is the most important prognostic factor for the decompensation of liver cirrhosis and death, therefore adequate care for patients with liver cirrhosis requires timely detection and evaluation of the presence of clinically significant PH(CSPH) and severe PH(SPH). As the most accurate method for the assessment of PH is an invasive direct measurement of hepatic venous pressure gradient(HVPG), the search for non-invasive methods to diagnose these conditions is actively ongoing.AIM To evaluate the feasibility of parameters of endogenously induced displacements and strain of liver to assess degree of PH.METHODS Of 36 patients with liver cirrhosis and measured HVPG were included in the casecontrol study. Endogenous motion of the liver was characterized by derived parameters of region average tissue displacement signal(dantero, dretro, d RMS) and results of endogenous tissue strain imaging using specific radiofrequency signal processing algorithm. Average endogenous strain μ and standard deviation σ of strain were assessed in the regions of interest(ROI)(1 cm × 1 cm and 2 cm × 2 cm in size) and different frequency subbands of endogenous motion(0-10 Hz and 10-20 Hz).RESULTS Four parameters showed statistically significant(P 0.05) correlation with HVPG measurement. The strongest correlation was obtained for the standard deviation of strain(estimated at 0-10 Hz and 2 cm × 2 cm ROI size). Three parameters showed statistically significant differences between patient groups with CSPH, but only dretro showed significant results in SPH analysis. According to ROC analysis area under the curve(AUC) of the σROI[0…10 Hz, 2 cm × 2 cm] parameter reached 0.71(P = 0.036) for the diagnosis of CSPH; with a cut-off value of 1.28 μm/cm providing 73% sensitivity and 70% specificity. AUC for the diagnosis of CSPH for μROI[0…10 Hz, 1 cm × 1 cm] was 0.78(P = 0.0024); with a cut-off value of 3.92 μm/cm providing 73% sensitivity and 80% specificity. Dretro parameter had an AUC of 0.86(P = 0.0001) for the diagnosis of CSPH and 0.84(P = 0.0001) for the diagnosis of SPH. A cut-off value of-132.34 μm yielded 100% sensitivity for both conditions, whereas specificity was 80% and 72% for CSPH and SPH respectively.CONCLUSION The parameters of endogenously induced displacements and strain of the liver correlated with HVPG and might be used for non-invasive diagnosis of PH.  相似文献   
9.
石颖  吴玲  李林苇 《中国临床康复》2006,10(48):151-153
目的:综述运动系统软组织损伤引起慢性疼痛的各种治疗方法的研究进展。资料来源:应用计算机检索Medline1980—01/2006—04与运动系统软组织损伤引起慢性疼痛的治疗相关文章,检索词“Soft tissue injury,pain.chronic,comprehensive therapy”,并限定文章语言种类为“English”;同时计算机检索中国期刊全文数据库1994—01/2006-04期间的相关文章,检索词“软组织损伤、慢性疼痛、治疗方法”,并限定语言种类为中文。同时手工查阅相关书籍。资料选择:对资料进行初审,所选文献内容符合:①软组织损伤引起的慢性疼痛药物治疗的研究。②软组织损伤引起的慢性疼痛微创治疗的研究。③软组织损伤引起的慢性疼痛运动疗法的研究。④软组织损伤引起的慢性疼痛心理治疗的研究。⑤软组织损伤引起的慢性疼痛其他疗法的研究。排除重复性研究的文献。资料提炼:共收集到40篇关于软组织损伤引起的慢性疼痛治疗方法的文献,均为全文,23篇符合纳入标准,排除17篇重复性研究。同时录入书籍3本。资料综合:软组织损伤引起的慢性疼痛的产生是生理、心理及社会因素复杂结合的结果,个体表现差异较大,目前尚无特效治疗方法,常用的治疗方法有:药物治疗、微创治疗、运动疗法、心理治疗、物理疗法及其他疗法。结论:对于软组织损伤引起的慢性疼痛的治疗必须以整体的观点对其进行合理的评估和个体化治疗,才能收到良好的效果。  相似文献   
10.
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