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   146043篇
  免费   45171篇
  国内免费   1143篇
耳鼻咽喉   2000篇
儿科学   5791篇
妇产科学   915篇
基础医学   28373篇
口腔科学   7291篇
临床医学   16837篇
内科学   31126篇
皮肤病学   4789篇
神经病学   21182篇
特种医学   6847篇
外国民族医学   5篇
外科学   17104篇
综合类   5713篇
一般理论   10篇
预防医学   10502篇
眼科学   1685篇
药学   15012篇
  101篇
中国医学   3008篇
肿瘤学   14066篇
  2023年   417篇
  2022年   936篇
  2021年   2675篇
  2020年   7104篇
  2019年   12536篇
  2018年   11976篇
  2017年   13114篇
  2016年   12220篇
  2015年   12053篇
  2014年   12769篇
  2013年   13182篇
  2012年   11970篇
  2011年   11978篇
  2010年   10470篇
  2009年   6883篇
  2008年   7525篇
  2007年   5875篇
  2006年   5497篇
  2005年   5074篇
  2004年   4926篇
  2003年   4532篇
  2002年   4128篇
  2001年   3313篇
  2000年   2054篇
  1999年   917篇
  1998年   617篇
  1997年   512篇
  1996年   474篇
  1995年   371篇
  1994年   348篇
  1993年   297篇
  1992年   222篇
  1991年   222篇
  1990年   180篇
  1989年   181篇
  1988年   126篇
  1986年   134篇
  1985年   487篇
  1984年   638篇
  1983年   497篇
  1982年   479篇
  1981年   453篇
  1980年   356篇
  1979年   327篇
  1978年   235篇
  1977年   174篇
  1976年   196篇
  1975年   190篇
  1974年   154篇
  1973年   147篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
81.
82.
83.
84.
Deep brain stimulation (DBS) in psychiatric illnesses has been clinically tested over the past 20 years. The clinical application of DBS to the superolateral branch of the medial forebrain bundle in treatment‐resistant depressed patients—one of several targets under investigation—has shown to be promising in a number of uncontrolled open label trials. However, there are remain numerous questions that need to be investigated to understand and optimize the clinical use of DBS in depression, including, for example, the relationship between the symptoms, the biological substrates/projections and the stimulation itself. In the context of precision and customized medicine, the current paper focuses on clinical and experimental research of medial forebrain bundle DBS in depression or in animal models of depression, demonstrating how clinical and scientific progress can work in tandem to test the therapeutic value and investigate the mechanisms of this experimental treatment. As one of the hypotheses is that depression engenders changes in the reward and motivational networks, the review looks at how stimulation of the medial forebrain bundle impacts the dopaminergic system.  相似文献   
85.
Increasing evidence suggests that human epidermal melanocytes play an important role in the skin immune system; however, a role of their pigmentation in immune and inflammatory responses is poorly examined. In the study, the expression of Toll‐like receptor 4 (TLR4) and inflammatory cytokines and chemokines by cultured normal melanocytes derived from lightly and darkly pigmented skin was investigated after cell stimulation with lipopolysaccharide (LPS). The basal TLR4 mRNA level in heavily pigmented cells was higher as compared to their lightly pigmented counterparts. Melanocyte exposure to LPS upregulated the expression of TLR4 mRNA and enhanced the DNA‐binding activity of NF‐κB p50 and p65. We found substantial differences in the LPS‐stimulated expression of numerous genes encoding inflammatory cytokines and chemokines between the cells with various melanin contents. In lightly pigmented melanocytes, the most significantly upregulated genes were nicotinamide phosphoribosyltransferase (NAMPT/visfatin), the chemokines CCL2 and CCL20, and IL6, while the genes for CXCL12, IL‐16 and the chemokine receptor CCR4 were the most significantly upregulated in heavily pigmented cells. Moreover, the lightly pigmented melanocytes secreted much more NAMPT, CCL2 and IL‐6. The results of our study suggest modulatory effect of melanogenesis on the immune properties of normal epidermal melanocytes.  相似文献   
86.
In the “basic” approach, medical expenses are catastrophic if they exceed a prespecified percentage of consumption or income; the approach tells us if expenses cause a large percentage reduction in living standards. The ability‐to‐pay (ATP) approach defines expenses as catastrophic if they exceed a prespecified percentage of consumption less expenses on nonmedical necessities or an allowance for them. The paper argues that the ATP approach does not tell us whether expenses are large enough to undermine a household's ability to purchase nonmedical necessities. The paper compares the income‐based and consumption‐based variants of the basic approach, and shows that if the individual is a borrower after a health shock, the income‐based ratio will exceed the consumption‐based ratio, and both will exceed the more theoretically correct Flores et al. ratio; whereas if the individual continues to be a saver after a health shock, the ordering is reversed and the income‐based ratio may not overestimate Flores et al.'s ratio. Last, the paper proposes a lifetime money metric utility (LMMU) approach defining medical expenses as catastrophic in terms of their lifetime consequences. Under certain assumptions, the LMMU and Flores et al. approaches are identical, and neither requires data on how households finance their medical expenses.  相似文献   
87.
88.
A pulmonary artery (PA) sling is a very rare congenital cardiovascular anomaly, and only a few studies have reported PA slings in fetuses. The relationship of the PA, aorta, ductus arteriosus, and trachea can be evaluated in the 3‐vessel and 3‐vessel and trachea views during fetal echocardiography. A PA sling can be detected by abnormal positioning of the left PA in relation to the trachea when sweeping from the 3‐vessel view cranially to the 3‐vessel and trachea view. Here we report 3 cases of fetal PA slings and their follow‐ups. Two cases were confirmed by postnatal echocardiography, and the other case was confirmed by a cardiovascular cast after pregnancy termination. We emphasize that the 3‐vessel and 3‐vessel and trachea views are of crucial importance in the prenatal diagnosis of a PA sling.  相似文献   
89.
目的探究糖化血红蛋白在糖尿病(DM)诊断中的应用价值。方法选取该院收治的36例糖尿病(DM)患者作为观察组,时间区间为2019年10月—2020年10月,实施糖化血红蛋白展开筛查和诊断,同时选择36名无糖尿病的健康者为对照组,分析并发症发生率、血糖指标、生活质量、心理状态评分等情况。结果观察组的空腹血糖、糖化血红蛋白和餐后2 h血糖的指标均高于对照组,差异有统计学意义(P<0.05);观察组经糖化血红蛋白展开筛查和诊断后,发现其各项生活质量评分均高于筛查诊断前,差异有统计学意义(P<0.05)。结论针对糖尿病(DM)患者,采用糖化血红蛋白展开筛查和诊断,可有效反映患者血糖改变情况,进一步提升临床上患者疾病诊断准确性,改善其不良负性心理情绪,提供可靠的参考资料,同时显著改善患者的生活质量,安全有效,具有临床应用价值。  相似文献   
90.
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