全文获取类型
收费全文 | 6994篇 |
免费 | 520篇 |
国内免费 | 377篇 |
专业分类
耳鼻咽喉 | 127篇 |
儿科学 | 150篇 |
妇产科学 | 115篇 |
基础医学 | 766篇 |
口腔科学 | 78篇 |
临床医学 | 1015篇 |
内科学 | 1066篇 |
皮肤病学 | 40篇 |
神经病学 | 494篇 |
特种医学 | 360篇 |
外国民族医学 | 4篇 |
外科学 | 650篇 |
综合类 | 763篇 |
预防医学 | 469篇 |
眼科学 | 185篇 |
药学 | 778篇 |
1篇 | |
中国医学 | 238篇 |
肿瘤学 | 592篇 |
出版年
2024年 | 15篇 |
2023年 | 69篇 |
2022年 | 169篇 |
2021年 | 246篇 |
2020年 | 201篇 |
2019年 | 174篇 |
2018年 | 180篇 |
2017年 | 168篇 |
2016年 | 177篇 |
2015年 | 215篇 |
2014年 | 324篇 |
2013年 | 297篇 |
2012年 | 400篇 |
2011年 | 474篇 |
2010年 | 305篇 |
2009年 | 225篇 |
2008年 | 308篇 |
2007年 | 385篇 |
2006年 | 349篇 |
2005年 | 362篇 |
2004年 | 275篇 |
2003年 | 237篇 |
2002年 | 246篇 |
2001年 | 136篇 |
2000年 | 162篇 |
1999年 | 209篇 |
1998年 | 163篇 |
1997年 | 160篇 |
1996年 | 132篇 |
1995年 | 126篇 |
1994年 | 108篇 |
1993年 | 108篇 |
1992年 | 88篇 |
1991年 | 76篇 |
1990年 | 64篇 |
1989年 | 84篇 |
1988年 | 56篇 |
1987年 | 54篇 |
1986年 | 44篇 |
1985年 | 40篇 |
1984年 | 36篇 |
1983年 | 33篇 |
1982年 | 26篇 |
1981年 | 25篇 |
1980年 | 31篇 |
1979年 | 17篇 |
1978年 | 18篇 |
1977年 | 16篇 |
1976年 | 11篇 |
1965年 | 8篇 |
排序方式: 共有7891条查询结果,搜索用时 15 毫秒
1.
2.
我院自1989年3月至1995年10月手术治疗21例创伤性膈疝,21例疝愈。 发病机理与胸腹腔压力差、腹腔脏器冲击膈肌及胸腔负压有关。同时简要介绍了创伤性膈疝的诊断和治疗。 相似文献
3.
4.
Mary Lou Galantino Michael Baime Maureen Maguire Philippe O Szapary John T Farrar 《Stress and health》2005,21(4):255-261
Work stress, burnout, and diminished empathy are prevalent issues for health‐care professionals. Mindfulness meditation (MM) is one commonly used strategy to manage stress. Measuring salivary cortisol allows for the assessment of serum cortisol level, a known stress level indicator. This study evaluated the association of subject‐reported stress symptoms and salivary cortisol in health‐care professionals, in an 8‐week MM program, with data collected prospectively at baseline and 8 weeks after program completion. Questionnaires [Profile of Mood States—Short Form (POMS‐SF), Maslach Burnout Inventory (MBI), and Interpersonal Reactivity Index (IRI)] measured mood, burnout and empathy. A paired t‐test between groups for pre/post‐salivary cortisol yielded no significant change. The POMS‐SF was most sensitive to change (mean increase 12.4; p = 0.020). Emotional exhaustion, measured in the MBI, was also affected by MM (mean decrease 4.54; p = 0.001). Changes in empathy may not have been captured due to either absence of effect of MM on empathy, subject number or scale sensitivity. Baseline and 8‐week correlations between salivary cortisol and survey results, and correlations between changes in these measures, were weak and not statistically significant. Nevertheless, psychometric results present a strong case for additional clinical trials of MM to reduce stress for health‐care professionals. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
5.
6.
Heterogeneity of cerebral vasoreactivity in preterm infants supported by mechanical ventilation 总被引:5,自引:0,他引:5
The reaction of cerebral blood flow to acute changes in arterial carbon dioxide pressure (PaCO2) and mean arterial blood pressure was determined in 57 preterm infants supported by mechanical ventilation (mean gestational age 30.1 weeks) during the first 48 hours of life. All infants had normal brain sonograms at the time of the investigation. In each infant, global cerebral blood flow was determined by xenon-133 clearance two to five times within a few hours at different levels of PaCO2. Changes in PaCO2 followed adjustments of the ventilator settings. Arterial oxygen pressure was intended to be kept constant, and mean arterial blood pressure fluctuated spontaneously between measurements. The data were analyzed by stepwise multiple regression, with changes in global cerebral blood flow, PaCO2, mean arterial blood pressure, and postnatal age or intracranial hemorrhage used as variables. In infants with persistently normal brain sonograms, the global cerebral blood flow-carbon dioxide reactivity was markedly lower during the first day of life (mean 11.2% to 11.8%/kPa PaCO2) compared with the second day of life (mean 32.6/kPa PaCO2), and pressure-flow autoregulation was preserved. Similarly, global cerebral blood flow-carbon dioxide reactivity and pressure-flow autoregulation were present in infants in whom mild intracranial hemorrhage developed after the study. In contrast, global cerebral blood flow reactivity to changes in PaCO2 and mean arterial blood pressure was absent in infants in whom ultrasonographic signs of severe intracranial hemorrhage subsequently developed. These infants also had about 20% lower global cerebral blood flow before hemorrhage, in comparison with infants whose sonograms were normal, a finding that suggests functional disturbances of cerebral blood flow regulation. Several perinatal factors were tested, but only birth after abruptio placentae was related to subsequent periventricular hemorrhage (p = 0.037). 相似文献
7.
Microsomal glutathione transferase 1 is not S-nitrosylated in rat liver microsomes or in endotoxin challenged rats. 总被引:1,自引:0,他引:1
In vitro activation of purified rat microsomal glutathione transferase 1 (MGST1) by S-nitrosylation has been recently reported. This study was designated to explore its in vivo relevance. Unexpectedly, we failed to detect S-nitrosylated MGST1 in rat liver microsomes treated with S-nitrosoglutathione (GSNO); neither did we observe MGST1 S-nitrosylation in endotoxin challenged rats. However, by using matrix-assisted laser dissociation/ionization time-of-flight mass spectrometry (MALDI-TOF MS), we identified several other proteins which are susceptible to S-nitrosylation in liver microsomes, including retinol dehydrogenase type I (RODH I), aldolase B, cytochrome P4502C11, and peroxiredoxin 1. Our results suggest that MGST1 S-nitrosylation is unlikely to be involved in the protection mechanism against nitrosative stress caused by endotoxin challenge. Further studies on the novel S-nitrosylable microsomal proteins are also warranted. 相似文献
8.
目的 对多分类有序反应变量logistic回归的应用条件寻求科学合理的检验方法。方法 使用卡方分布的理论,SAS软件及抽样调查方法。结果 设计出多分类有序反应变量logistic回归应用条件的卡方检验方法,推导出反应变量取各水平的概率计算公式及卡方检验中理论值、自由度的计算公式,并在作者主持的国家医师资格临床实践技能考试研究中取得了成功效果。结论 多分类有序反应变量logistic回归得到完善和补充,具有较大的理论和实际意义。 相似文献
9.
10.